00
Correct
00
Incorrect
00 : 00 : 00
Session Time
00 : 00
Average Question Time ( Secs)
  • Question 1 - Samantha is a 67-year-old woman who visits her doctor complaining of muscle weakness...

    Incorrect

    • Samantha is a 67-year-old woman who visits her doctor complaining of muscle weakness and blurred vision. She works as a librarian, drinks about 15 units of alcohol per week, and has smoked about 25 cigarettes a day for 35 years.

      During the examination, her blood pressure is found to be elevated at 152/98 mmHg. There are reduced breath sounds over the area of the right lower lobe. Some of her blood test results are as follows:

      - Hb 120 g/L (Female: 115-160)
      - Platelets 420 * 109/L (150-400)
      - WBC 9.1 * 109/L (4.0-11.0)
      - Na+ 148 mmol/L (135-145)
      - K+ 3.2 mmol/L (3.5-5.0)
      - Urea 8.5 mmol/L (2.0-7.0)
      - Creatinine 150 µmol/L (55-120)
      - 24-hour urine free cortisol 260 ug/l (10-100)
      - Glucose 17.8 mmol/l (4.0-7.0)

      She mentions that, aside from a persistent cough due to smoking, which occasionally produces blood, she feels fine.

      What is the most probable diagnosis?

      Your Answer: Squamous cell lung carcinoma

      Correct Answer: Small cell lung carcinoma

      Explanation:

      A small cell lung carcinoma that secretes ACTH can lead to Cushing’s syndrome, as seen in this patient. The history and examination findings suggest lung cancer, and the raised cortisol level can be explained by the paraneoplastic syndrome caused by ACTH release. Muscle weakness and blurred vision are typical symptoms of Cushing’s syndrome. Squamous cell lung carcinoma and adrenal adenoma are less likely causes, while Cushing’s disease is not applicable in this case.

      Lung cancer can present with paraneoplastic features, which are symptoms caused by the cancer but not directly related to the tumor itself. Small cell lung cancer can cause the secretion of ADH and, less commonly, ACTH, which can lead to hypertension, hyperglycemia, hypokalemia, alkalosis, and muscle weakness. Lambert-Eaton syndrome is also associated with small cell lung cancer. Squamous cell lung cancer can cause the secretion of parathyroid hormone-related protein, leading to hypercalcemia, as well as clubbing and hypertrophic pulmonary osteoarthropathy. Adenocarcinoma can cause gynecomastia and hypertrophic pulmonary osteoarthropathy. Hypertrophic pulmonary osteoarthropathy is a painful condition involving the proliferation of periosteum in the long bones. Although traditionally associated with squamous cell carcinoma, some studies suggest that adenocarcinoma is the most common cause.

    • This question is part of the following fields:

      • Respiratory System
      39.9
      Seconds
  • Question 2 - A 72-year-old man with thyroid cancer is hospitalized for dyspnea. What is the...

    Incorrect

    • A 72-year-old man with thyroid cancer is hospitalized for dyspnea. What is the most appropriate test to evaluate potential compression of the upper respiratory tract?

      Your Answer: Forced vital capacity

      Correct Answer: Flow volume loop

      Explanation:

      Understanding Flow Volume Loops

      A flow volume loop is a graphical representation of the amount of air that a person can inhale and exhale over time. It is often described as a triangle on top of a semi-circle. This loop is useful in assessing the compression of the upper airway, which can be caused by various conditions such as asthma, chronic obstructive pulmonary disease (COPD), and sleep apnea.

      To interpret a flow volume loop, the vertical axis represents the flow rate, while the horizontal axis represents the volume of air. The loop starts at the bottom left corner, where the person begins to inhale. As the person inhales, the flow rate increases, creating the upward slope of the triangle. At the top of the triangle, the person reaches their maximum inhalation volume.

      The person then begins to exhale, creating the downward slope of the triangle. The flow rate decreases as the person exhales, until they reach their maximum exhalation volume, represented by the semi-circle. The loop then returns to the starting point, completing one full cycle.

      Overall, flow volume loops are a valuable tool in diagnosing and monitoring respiratory conditions. By analyzing the shape and size of the loop, healthcare professionals can identify abnormalities in lung function and determine the appropriate treatment plan.

    • This question is part of the following fields:

      • Respiratory System
      9.5
      Seconds
  • Question 3 - A 29-year-old man visits his primary care physician with complaints of a malodorous...

    Incorrect

    • A 29-year-old man visits his primary care physician with complaints of a malodorous discharge from his right ear for the past 3 weeks. The patient also reports experiencing ear pain for the past 2 weeks and occasional mild dizziness. Upon examination, the skin around the ear and pinna appear normal, but the ear canal is filled with debris. After removing the debris, a small perforation and waxy debris are observed on the tympanic membrane.

      The Rinne test indicates that bone conduction is better than air conduction on the right, and the Weber test shows sound lateralization to the right. The patient has no significant medical history and has never presented with an ear problem before.

      What is the most likely condition based on this patient's clinical presentation?

      Your Answer: Otitis media

      Correct Answer: Cholesteatoma

      Explanation:

      Cholesteatoma is a growth of non-cancerous squamous epithelium that can be observed as an ‘attic crust’ during otoscopy. This patient is displaying symptoms consistent with cholesteatoma, including ear discharge, earache, conductive hearing loss, and dizziness, which suggests that the inner ear has also been affected. It is important to distinguish cholesteatoma from otitis externa, as failure to diagnose cholesteatoma can lead to serious complications. Cholesteatoma can erode the ossicles bones, damage the inner ear and vestibulocochlear nerve, and even result in brain infections if it erodes through the skull bone.

      Otitis externa is an inflammation of the outer ear canal that causes ear pain, which worsens with movement of the outer ear. It is often caused by the use of earplugs or swimming in unclean water. Otitis media is an inflammation of the middle ear that can lead to fluid accumulation and perforation of the tympanic membrane. It is common in children and often follows a viral upper respiratory tract infection. Myringitis is a condition associated with otitis media that causes small vesicles or cysts to form on the surface of the eardrum, resulting in severe pain and hearing impairment. It is caused by viral or bacterial infections and is treated with pain relief and antibiotics.

      Understanding Cholesteatoma

      Cholesteatoma is a benign growth of squamous epithelium that can cause damage to the skull base. It is most commonly found in individuals between the ages of 10 and 20 years old. Those born with a cleft palate are at a higher risk of developing cholesteatoma, with a 100-fold increase in risk.

      The main symptoms of cholesteatoma include a persistent discharge with a foul odor and hearing loss. Other symptoms may occur depending on the extent of the growth, such as vertigo, facial nerve palsy, and cerebellopontine angle syndrome.

      During otoscopy, a characteristic attic crust may be seen in the uppermost part of the eardrum.

      Management of cholesteatoma involves referral to an ear, nose, and throat specialist for surgical removal. Early detection and treatment are important to prevent further damage to the skull base and surrounding structures.

      In summary, cholesteatoma is a non-cancerous growth that can cause significant damage if left untreated. It is important to be aware of the symptoms and seek medical attention promptly if they occur.

    • This question is part of the following fields:

      • Respiratory System
      59
      Seconds
  • Question 4 - A 38-year-old male presents to the hospital with recurrent nose bleeds, joint pain,...

    Incorrect

    • A 38-year-old male presents to the hospital with recurrent nose bleeds, joint pain, chronic sinusitis, and haemoptysis for the past 3 days. During the examination, the doctor observes a saddle-shaped nose and a necrotic, purpuric, and blistering plaque on his wrist. The patient reports that he had a small blister a few weeks ago, which has now progressed to this. The blood test results suggest a possible diagnosis of granulomatosis with polyangiitis, and the patient is referred for a renal biopsy. What biopsy findings would confirm the suspected diagnosis?

      Your Answer: Diffuse increase in mesangial cells

      Correct Answer: Epithelial crescents in Bowman's capsule

      Explanation:

      Glomerulonephritis is a condition that affects the kidneys and can present with various pathological changes. In rapidly progressive glomerulonephritis, patients may present with respiratory tract symptoms and cutaneous manifestations of vasculitis. Renal biopsy will show epithelial crescents in Bowman’s capsule, indicating severe glomerular injury. Mesangioproliferative glomerulonephritis is characterized by a diffuse increase in mesangial cells and is not associated with respiratory tract symptoms or cutaneous manifestations of vasculitis. Membranoproliferative glomerulonephritis involves deposits in the intraglomerular mesangium and is associated with activation of the complement pathway and glomerular damage. It is unlikely to be the diagnosis in the scenario as it is not associated with vasculitis symptoms. A normal nephron architecture would not explain the patient’s symptoms and is an incorrect answer.

      Granulomatosis with Polyangiitis: An Autoimmune Condition

      Granulomatosis with polyangiitis, previously known as Wegener’s granulomatosis, is an autoimmune condition that affects the upper and lower respiratory tract as well as the kidneys. It is characterized by a necrotizing granulomatous vasculitis. The condition presents with various symptoms such as epistaxis, sinusitis, nasal crusting, dyspnoea, haemoptysis, and rapidly progressive glomerulonephritis. Other symptoms include a saddle-shape nose deformity, vasculitic rash, eye involvement, and cranial nerve lesions.

      To diagnose granulomatosis with polyangiitis, doctors perform various investigations such as cANCA and pANCA tests, chest x-rays, and renal biopsies. The cANCA test is positive in more than 90% of cases, while the pANCA test is positive in 25% of cases. Chest x-rays show a wide variety of presentations, including cavitating lesions. Renal biopsies reveal epithelial crescents in Bowman’s capsule.

      The management of granulomatosis with polyangiitis involves the use of steroids, cyclophosphamide, and plasma exchange. Cyclophosphamide has a 90% response rate. The median survival rate for patients with this condition is 8-9 years.

    • This question is part of the following fields:

      • Respiratory System
      52.9
      Seconds
  • Question 5 - A 55-year-old man comes to the hospital complaining of lethargy, headache, and shortness...

    Correct

    • A 55-year-old man comes to the hospital complaining of lethargy, headache, and shortness of breath. Upon examination, he is found to be cyanotic and hypoxic, and is admitted to the respiratory ward for oxygen therapy.

      Following some initial tests, the consultant informs the patient that his hemoglobin has a high affinity for oxygen, resulting in reduced oxygen delivery to the tissues.

      What is the probable reason for this alteration in the oxygen dissociation curve?

      Your Answer: Low 2,3-DPG

      Explanation:

      The correct answer is low 2,3-DPG. The professor’s description refers to a left shift in the oxygen dissociation curve, which indicates that haemoglobin has a high affinity for oxygen and is less likely to release it to the tissues. Factors that cause a left shift include low temperature, high pH, low PCO2, and low 2,3-DPG. 2,3-DPG is a substance that helps release oxygen from haemoglobin, so low levels of it result in less oxygen being released, causing a left shift in the oxygen dissociation curve.

      The answer high temperature is incorrect because it causes a right shift in the oxygen dissociation curve, promoting oxygen delivery to the tissues. Hypercapnoea also causes a right shift in the curve, promoting oxygen delivery. Hyperglycaemia has no effect on haemoglobin’s ability to release oxygen, so it is also incorrect.

      Understanding the Oxygen Dissociation Curve

      The oxygen dissociation curve is a graphical representation of the relationship between the percentage of saturated haemoglobin and the partial pressure of oxygen in the blood. It is not influenced by the concentration of haemoglobin. The curve can shift to the left or right, indicating changes in oxygen delivery to tissues. When the curve shifts to the left, there is increased saturation of haemoglobin with oxygen, resulting in decreased oxygen delivery to tissues. Conversely, when the curve shifts to the right, there is reduced saturation of haemoglobin with oxygen, leading to enhanced oxygen delivery to tissues.

      The L rule is a helpful mnemonic to remember the factors that cause a shift to the left, resulting in lower oxygen delivery. These factors include low levels of hydrogen ions (alkali), low partial pressure of carbon dioxide, low levels of 2,3-diphosphoglycerate, and low temperature. On the other hand, the mnemonic ‘CADET, face Right!’ can be used to remember the factors that cause a shift to the right, leading to raised oxygen delivery. These factors include carbon dioxide, acid, 2,3-diphosphoglycerate, exercise, and temperature.

      Understanding the oxygen dissociation curve is crucial in assessing the oxygen-carrying capacity of the blood and the delivery of oxygen to tissues. By knowing the factors that can shift the curve to the left or right, healthcare professionals can make informed decisions in managing patients with respiratory and cardiovascular diseases.

    • This question is part of the following fields:

      • Respiratory System
      35.5
      Seconds
  • Question 6 - A 49-year-old man experiences blunt force trauma to the head and subsequently experiences...

    Incorrect

    • A 49-year-old man experiences blunt force trauma to the head and subsequently experiences respiratory distress, leading to hypercapnia. What is the most probable consequence of this condition?

      Your Answer: None of the above

      Correct Answer: Cerebral vasodilation

      Explanation:

      Cerebral vasodilation is a common result of hypercapnia, which can be problematic for patients with cranial trauma due to the potential increase in intracranial pressure.

      Understanding the Monro-Kelly Doctrine and Autoregulation in the CNS

      The Monro-Kelly doctrine governs the pressure within the cranium by considering the skull as a closed box. The loss of cerebrospinal fluid (CSF) can accommodate increases in mass until a critical point is reached, usually at 100-120ml of CSF lost. Beyond this point, intracranial pressure (ICP) rises sharply, and pressure will eventually equate with mean arterial pressure (MAP), leading to neuronal death and herniation.

      The central nervous system (CNS) has the ability to autoregulate its own blood supply through vasoconstriction and dilation of cerebral blood vessels. However, extreme blood pressure levels can exceed this capacity, increasing the risk of stroke. Additionally, metabolic factors such as hypercapnia can cause vasodilation, which is crucial in ventilating head-injured patients.

      It is important to note that the brain can only metabolize glucose, and a decrease in glucose levels can lead to impaired consciousness. Understanding the Monro-Kelly doctrine and autoregulation in the CNS is crucial in managing intracranial pressure and preventing neurological damage.

    • This question is part of the following fields:

      • Respiratory System
      37.3
      Seconds
  • Question 7 - A 63-year-old man arrives at the ER with a recent onset of left-sided...

    Incorrect

    • A 63-year-old man arrives at the ER with a recent onset of left-sided facial paralysis. He reports experiencing a painful rash around his ear on the affected side for the past five days. Your suspicion is Ramsay Hunt syndrome. What virus is responsible for this condition?

      Your Answer: Herpes simplex virus

      Correct Answer: Varicella zoster virus

      Explanation:

      The geniculate ganglion of the facial nerve (CN VII) reactivates the varicella-zoster virus, causing Ramsay Hunt syndrome.

      Infectious mononucleosis (glandular fever) is primarily linked to the Epstein-Barr virus.

      Viral warts are commonly caused by human papillomavirus (HPV), with certain types being associated with gynaecological malignancy. Vaccines are now available to protect against the carcinogenic strains of HPV.

      Oral or genital herpes infections are caused by the herpes simplex virus.

      Understanding Ramsay Hunt Syndrome

      Ramsay Hunt syndrome, also known as herpes zoster oticus, is a condition that occurs when the varicella zoster virus reactivates in the geniculate ganglion of the seventh cranial nerve. The first symptom of this syndrome is often auricular pain, followed by facial nerve palsy and a vesicular rash around the ear. Other symptoms may include vertigo and tinnitus.

      To manage Ramsay Hunt syndrome, doctors typically prescribe oral acyclovir and corticosteroids. These medications can help reduce the severity of symptoms and prevent complications.

    • This question is part of the following fields:

      • Respiratory System
      11
      Seconds
  • Question 8 - A 27-year-old man with a history of epilepsy is admitted to the hospital...

    Incorrect

    • A 27-year-old man with a history of epilepsy is admitted to the hospital after experiencing a tonic-clonic seizure. He is currently taking sodium valproate as his only medication. A venous blood gas is obtained immediately.

      What are the expected venous blood gas results for this patient?

      Your Answer: High pH, normal lactate, low SaO2

      Correct Answer: Low pH, high lactate, low SaO2

      Explanation:

      Acidosis shifts the oxygen dissociation curve to the right, which enhances oxygen delivery to the tissues by causing more oxygen to dissociate from Hb. postictal lactic acidosis is a common occurrence in patients with tonic-clonic seizures, and it is typically managed by monitoring for spontaneous resolution. During a seizure, tissue hypoxia can cause lactic acidosis. Therefore, a venous blood gas test for this patient should show low pH, high lactate, and low SaO2.

      If the venous blood gas test shows a high pH, normal lactate, and low SaO2, it would not be consistent with postictal lactic acidosis. This result indicates alkalosis, which can be caused by gastrointestinal losses, renal losses, or Cushing syndrome.

      A high pH, normal lactate, and normal SaO2 would also be inconsistent with postictal lactic acidosis because tissue hypoxia would cause an increase in lactate levels.

      Similarly, low pH, high lactate, and normal SaO2 would not be expected in postictal lactic acidosis because acidosis would shift the oxygen dissociation curve to the right, decreasing the oxygen saturation of haemoglobin.

      Finally, normal pH, normal lactate, and normal SaO2 are unlikely to be found in this patient shortly after a seizure. However, if the venous blood gas test was taken days after the seizure following an uncomplicated clinical course, these findings would be more plausible.

      Understanding the Oxygen Dissociation Curve

      The oxygen dissociation curve is a graphical representation of the relationship between the percentage of saturated haemoglobin and the partial pressure of oxygen in the blood. It is not influenced by the concentration of haemoglobin. The curve can shift to the left or right, indicating changes in oxygen delivery to tissues. When the curve shifts to the left, there is increased saturation of haemoglobin with oxygen, resulting in decreased oxygen delivery to tissues. Conversely, when the curve shifts to the right, there is reduced saturation of haemoglobin with oxygen, leading to enhanced oxygen delivery to tissues.

      The L rule is a helpful mnemonic to remember the factors that cause a shift to the left, resulting in lower oxygen delivery. These factors include low levels of hydrogen ions (alkali), low partial pressure of carbon dioxide, low levels of 2,3-diphosphoglycerate, and low temperature. On the other hand, the mnemonic ‘CADET, face Right!’ can be used to remember the factors that cause a shift to the right, leading to raised oxygen delivery. These factors include carbon dioxide, acid, 2,3-diphosphoglycerate, exercise, and temperature.

      Understanding the oxygen dissociation curve is crucial in assessing the oxygen-carrying capacity of the blood and the delivery of oxygen to tissues. By knowing the factors that can shift the curve to the left or right, healthcare professionals can make informed decisions in managing patients with respiratory and cardiovascular diseases.

    • This question is part of the following fields:

      • Respiratory System
      27.9
      Seconds
  • Question 9 - An 80-year-old man with metastatic lung cancer arrives at the acute medical unit...

    Correct

    • An 80-year-old man with metastatic lung cancer arrives at the acute medical unit with sudden shortness of breath. A chest x-ray shows a malignant pleural effusion encasing the right lung. The medical registrar intends to perform a pleural tap to drain the effusion and send a sample to the lab. The registrar takes into account the effusion's position around the lung. What is the minimum level of the effusion in the mid-axillary line?

      Your Answer: 10th rib

      Explanation:

      The parietal pleura can be found at the 10th rib in the mid-axillary line, while the visceral pleura is closely attached to the lung tissue and can be considered as one. The location of the parietal pleura is more inferior than that of the visceral pleura, with the former being at the 8th rib in the midclavicular line and the 10th rib in the midaxillary line. The location of the parietal pleura in the scapular line is not specified.

      Anatomy of the Lungs

      The lungs are a pair of organs located in the chest cavity that play a vital role in respiration. The right lung is composed of three lobes, while the left lung has two lobes. The apex of both lungs is approximately 4 cm superior to the sternocostal joint of the first rib. The base of the lungs is in contact with the diaphragm, while the costal surface corresponds to the cavity of the chest. The mediastinal surface contacts the mediastinal pleura and has the cardiac impression. The hilum is a triangular depression above and behind the concavity, where the structures that form the root of the lung enter and leave the viscus. The right main bronchus is shorter, wider, and more vertical than the left main bronchus. The inferior borders of both lungs are at the 6th rib in the mid clavicular line, 8th rib in the mid axillary line, and 10th rib posteriorly. The pleura runs two ribs lower than the corresponding lung level. The bronchopulmonary segments of the lungs are divided into ten segments, each with a specific function.

    • This question is part of the following fields:

      • Respiratory System
      13.6
      Seconds
  • Question 10 - A 29-year-old man comes to the clinic with a complaint of ear pain....

    Incorrect

    • A 29-year-old man comes to the clinic with a complaint of ear pain. He mentions that the pain started yesterday and has been preventing him from working. He also reports experiencing dizziness and muffled sounds on the affected side. During the examination, you notice that he has a fever and a bulging tympanic membrane with visible fluid. Based on these symptoms, you suspect that he has a middle ear infection. Now, you wonder which ossicle the tensor tympani muscle inserts into.

      Which ossicle does the tensor tympani muscle insert into?

      Your Answer: Stapes

      Correct Answer: Malleus

      Explanation:

      The tensor tympani muscle is located in a bony canal above the pharyngotympanic tube and originates from the cartilaginous portion of the tube, the bony canal, and the greater wing of the sphenoid bone. Its function is to reduce the magnitude of vibrations transmitted into the middle ear by pulling the handle of the malleus medially when contracted. This muscle is innervated by the nerve to tensor tympani, which arises from the mandibular nerve.

      The middle ear contains three ossicles, which are the malleus, incus, and stapes. The malleus is the most lateral and attaches to the tympanic membrane, while the incus lies between and articulates with the other two ossicles. The stapes is the most medial and is connected to the oval window of the cochlea. The stapedius muscle is associated with the stapes. The lunate and trapezium are not bones of the middle ear but are carpal bones.

      A patient with ear pain, difficulty hearing, dizziness, and fever may have otitis media, which is confirmed on otoscopy by a bulging tympanic membrane and visible fluid level.

      Anatomy of the Ear

      The ear is divided into three distinct regions: the external ear, middle ear, and internal ear. The external ear consists of the auricle and external auditory meatus, which are innervated by the greater auricular nerve and auriculotemporal branch of the trigeminal nerve. The middle ear is the space between the tympanic membrane and cochlea, and is connected to the nasopharynx by the eustachian tube. The tympanic membrane is composed of three layers and is approximately 1 cm in diameter. The middle ear is innervated by the glossopharyngeal nerve. The ossicles, consisting of the malleus, incus, and stapes, transmit sound vibrations from the tympanic membrane to the inner ear. The internal ear contains the cochlea, which houses the organ of corti, the sense organ of hearing. The vestibule accommodates the utricule and saccule, which contain endolymph and are surrounded by perilymph. The semicircular canals, which share a common opening into the vestibule, lie at various angles to the petrous temporal bone.

    • This question is part of the following fields:

      • Respiratory System
      30.3
      Seconds
  • Question 11 - A 50-year-old man with laryngeal cancer is undergoing a challenging laryngectomy. During the...

    Correct

    • A 50-year-old man with laryngeal cancer is undergoing a challenging laryngectomy. During the procedure, the surgeons cut the thyrocervical trunk. What vessel does this structure typically originate from?

      Your Answer: Subclavian artery

      Explanation:

      The subclavian artery gives rise to the thyrocervical trunk, which emerges from the first part of the artery located between the inner border of scalenus anterior and the subclavian artery. The thyrocervical trunk branches off from the subclavian artery after the vertebral artery.

      Thoracic Outlet: Where the Subclavian Artery and Vein and Brachial Plexus Exit the Thorax

      The thoracic outlet is the area where the subclavian artery and vein and the brachial plexus exit the thorax and enter the arm. This passage occurs over the first rib and under the clavicle. The subclavian vein is the most anterior structure and is located immediately in front of scalenus anterior and its attachment to the first rib. Scalenus anterior has two parts, and the subclavian artery leaves the thorax by passing over the first rib and between these two portions of the muscle. At the level of the first rib, the lower cervical nerve roots combine to form the three trunks of the brachial plexus. The lowest trunk is formed by the union of C8 and T1, and this trunk lies directly posterior to the artery and is in contact with the superior surface of the first rib.

      Thoracic outlet obstruction can cause neurovascular compromise.

    • This question is part of the following fields:

      • Respiratory System
      9.4
      Seconds
  • Question 12 - A 9-year-old boy is rushed to the emergency department following a fish bone...

    Correct

    • A 9-year-old boy is rushed to the emergency department following a fish bone choking incident during dinner. The patient is not experiencing any airway obstruction and has been given sufficient pain relief.

      After being referred for laryngoscopy, a fish bone is discovered in the piriform recess. What is the potential structure that could be harmed due to the location of the fish bone?

      Your Answer: Internal laryngeal nerve

      Explanation:

      Foreign objects lodged in the piriform recess can cause damage to the internal laryngeal nerve, which is in close proximity to this area. The internal laryngeal nerve is responsible for providing sensation to the laryngeal mucosa. The ansa cervicalis, external laryngeal nerve, glossopharyngeal nerve, and superior laryngeal nerve are not at high risk of injury from foreign bodies in the piriform recess.

      Anatomy of the Larynx

      The larynx is located in the front of the neck, between the third and sixth cervical vertebrae. It is made up of several cartilaginous segments, including the paired arytenoid, corniculate, and cuneiform cartilages, as well as the single thyroid, cricoid, and epiglottic cartilages. The cricoid cartilage forms a complete ring. The laryngeal cavity extends from the laryngeal inlet to the inferior border of the cricoid cartilage and is divided into three parts: the laryngeal vestibule, the laryngeal ventricle, and the infraglottic cavity.

      The vocal folds, also known as the true vocal cords, control sound production. They consist of the vocal ligament and the vocalis muscle, which is the most medial part of the thyroarytenoid muscle. The glottis is composed of the vocal folds, processes, and rima glottidis, which is the narrowest potential site within the larynx.

      The larynx is also home to several muscles, including the posterior cricoarytenoid, lateral cricoarytenoid, thyroarytenoid, transverse and oblique arytenoids, vocalis, and cricothyroid muscles. These muscles are responsible for various actions, such as abducting or adducting the vocal folds and relaxing or tensing the vocal ligament.

      The larynx receives its arterial supply from the laryngeal arteries, which are branches of the superior and inferior thyroid arteries. Venous drainage is via the superior and inferior laryngeal veins. Lymphatic drainage varies depending on the location within the larynx, with the vocal cords having no lymphatic drainage and the supraglottic and subglottic parts draining into different lymph nodes.

      Overall, understanding the anatomy of the larynx is important for proper diagnosis and treatment of various conditions affecting this structure.

    • This question is part of the following fields:

      • Respiratory System
      18.1
      Seconds
  • Question 13 - A 23-year-old woman comes to your clinic complaining of difficulty hearing her partner...

    Incorrect

    • A 23-year-old woman comes to your clinic complaining of difficulty hearing her partner at home. She has been experiencing a high-pitched ringing in her left ear for the past 6 months. She attributes this to attending loud concerts frequently and has not sought medical attention until now. She reports that she can hear better when she is outside but struggles in quiet environments. Upon examination, there are no abnormalities seen during otoscopy. One of the possible diagnoses for this patient is otosclerosis, a condition that primarily affects the stapes bone. Which structure does the stapes bone come into contact with in the cochlea?

      Your Answer: Organ of Corti

      Correct Answer: Oval window

      Explanation:

      The oval window is where the stapes connects with the cochlea, and it is the most inner of the ossicles. The stapes has a stirrup-like shape, with a head that articulates with the incus and two limbs that connect it to the base. The base of the stapes is in contact with the oval window, which is one of the only two openings between the middle and inner ear. The organ of Corti, which is responsible for hearing, is located on the basilar membrane within the cochlear duct. The round window is the other opening between the middle and inner ear, and it allows the fluid within the cochlea to move, transmitting sound to the hair cells. The helicotrema is the point where the scala tympani and scala vestibuli meet at the apex of the cochlear labyrinth. The tectorial membrane is a membrane that extends along the entire length of the cochlea. A female in her third decade of life with unilateral conductive hearing loss and a family history of hearing loss is likely to have otosclerosis, a condition that affects the stapes and can cause severe or total hearing loss due to abnormal bone growth and fusion with the cochlea.

      Anatomy of the Ear

      The ear is divided into three distinct regions: the external ear, middle ear, and internal ear. The external ear consists of the auricle and external auditory meatus, which are innervated by the greater auricular nerve and auriculotemporal branch of the trigeminal nerve. The middle ear is the space between the tympanic membrane and cochlea, and is connected to the nasopharynx by the eustachian tube. The tympanic membrane is composed of three layers and is approximately 1 cm in diameter. The middle ear is innervated by the glossopharyngeal nerve. The ossicles, consisting of the malleus, incus, and stapes, transmit sound vibrations from the tympanic membrane to the inner ear. The internal ear contains the cochlea, which houses the organ of corti, the sense organ of hearing. The vestibule accommodates the utricule and saccule, which contain endolymph and are surrounded by perilymph. The semicircular canals, which share a common opening into the vestibule, lie at various angles to the petrous temporal bone.

    • This question is part of the following fields:

      • Respiratory System
      32.4
      Seconds
  • Question 14 - A 56-year-old woman comes to the clinic complaining of a persistent cough and...

    Incorrect

    • A 56-year-old woman comes to the clinic complaining of a persistent cough and increased production of sputum over the past year. She also reports feeling fatigued and experiencing shortness of breath. The patient mentions having had four chest infections in the last 12 months, all of which were treated with antibiotics. She has no personal or family history of lung issues and has never smoked.

      The healthcare provider suspects that bronchiectasis may be the underlying cause of her symptoms and orders appropriate tests.

      Which test is most likely to provide a definitive diagnosis?

      Your Answer: Pulmonary function test

      Correct Answer: High-resolution computerised tomography

      Explanation:

      Bronchiectasis can be diagnosed through various methods, including chest radiography, histopathology, and pulmonary function tests.

      Chest radiography can reveal thickened bronchial walls, cystic lesions with fluid levels, collapsed areas with crowded pulmonary vasculature, and scarring, which are characteristic features of bronchiectasis.

      Histopathology, which is a more invasive investigation often done through autopsy or surgery, can show irreversible dilation of bronchial airways and bronchial wall thickening.

      However, high-resolution computerised tomography is a more favorable imaging technique as it is less invasive than histopathology.

      Pulmonary function tests are commonly used to diagnose bronchiectasis, but they should be used in conjunction with other investigations as they are not sensitive or specific enough to provide sufficient diagnostic evidence on their own. An obstructive pattern is the most common pattern encountered, but a restrictive pattern is also possible.

      Understanding the Causes of Bronchiectasis

      Bronchiectasis is a condition characterized by the permanent dilation of the airways due to chronic inflammation or infection. There are various factors that can lead to this condition, including post-infective causes such as tuberculosis, measles, pertussis, and pneumonia. Cystic fibrosis, bronchial obstruction caused by lung cancer or foreign bodies, and immune deficiencies like selective IgA and hypogammaglobulinaemia can also contribute to bronchiectasis. Additionally, allergic bronchopulmonary aspergillosis (ABPA), ciliary dyskinetic syndromes like Kartagener’s syndrome and Young’s syndrome, and yellow nail syndrome are other potential causes. Understanding the underlying causes of bronchiectasis is crucial in developing effective treatment plans for patients.

    • This question is part of the following fields:

      • Respiratory System
      15.2
      Seconds
  • Question 15 - A 10-year-old boy is recuperating the day after a tonsillectomy. His parents report...

    Incorrect

    • A 10-year-old boy is recuperating the day after a tonsillectomy. His parents report that he hasn't had anything to eat for 6 hours prior to the surgery and he is feeling famished. However, he is declining any attempts to consume food or water. There are no prescribed medications or known drug allergies listed on his medical records.

      What would be the most appropriate first step to take?

      Your Answer: Start maintenance fluids

      Correct Answer: Prescribe analgesia and encourage oral intake

      Explanation:

      Effective pain management is crucial after a tonsillectomy to promote the consumption of food and fluids.

      Prescribing analgesics and encouraging oral intake is the best course of action. This will alleviate pain and enable the patient to eat and drink, which is essential for a speedy recovery.

      Starting maintenance fluids or partial nutritional feeds, obtaining IV access, or waiting for two hours before reviewing the patient are not the most appropriate options. Analgesia should be the primary consideration to facilitate oral fluid therapy and promote healing.

      Tonsillitis and Tonsillectomy: Complications and Indications

      Tonsillitis is a condition that can lead to various complications, including otitis media, peritonsillar abscess, and, in rare cases, rheumatic fever and glomerulonephritis. Tonsillectomy, the surgical removal of the tonsils, is a controversial procedure that should only be considered if the person meets specific criteria. According to NICE, surgery should only be considered if the person experiences sore throats due to tonsillitis, has five or more episodes of sore throat per year, has been experiencing symptoms for at least a year, and the episodes of sore throat are disabling and prevent normal functioning. Other established indications for a tonsillectomy include recurrent febrile convulsions, obstructive sleep apnoea, stridor, dysphagia, and peritonsillar abscess if unresponsive to standard treatment.

      Despite the benefits of tonsillectomy, the procedure also carries some risks. Primary complications, which occur within 24 hours of the surgery, include haemorrhage and pain. Secondary complications, which occur between 24 hours to 10 days after the surgery, include haemorrhage (most commonly due to infection) and pain. Therefore, it is essential to weigh the benefits and risks of tonsillectomy before deciding to undergo the procedure.

    • This question is part of the following fields:

      • Respiratory System
      20.3
      Seconds
  • Question 16 - During a radical neck dissection, at what age would division of which of...

    Incorrect

    • During a radical neck dissection, at what age would division of which of the following fascial layers expose the ansa cervicalis?

      Your Answer: Prevertebral fascia

      Correct Answer: Pretracheal fascia

      Explanation:

      To access the ansa cervicalis, one must cut through the pretracheal fascia on the posterolateral side of the thyroid gland. This nerve is located in front of the carotid sheath. However, it should be noted that the pre vertebral fascia is situated further back and cannot be reached by dividing the investing layer of fascia.

      The ansa cervicalis is a nerve that provides innervation to the sternohyoid, sternothyroid, and omohyoid muscles. It is composed of two roots: the superior root, which branches off from C1 and is located anterolateral to the carotid sheath, and the inferior root, which is derived from the C2 and C3 roots and passes posterolateral to the internal jugular vein. The inferior root enters the inferior aspect of the strap muscles, which are located in the neck, and should be divided in their upper half when exposing a large goitre. The ansa cervicalis is situated in front of the carotid sheath and is an important nerve for the proper functioning of the neck muscles.

    • This question is part of the following fields:

      • Respiratory System
      5.8
      Seconds
  • Question 17 - A 26-year-old male is brought to the emergency department by his mother. He...

    Correct

    • A 26-year-old male is brought to the emergency department by his mother. He is agitated, restless, and anxious.

      Upon examination, dilated pupils are observed, and an ECG reveals sinus tachycardia.

      The patient has a medical history of chronic asthma and is currently taking modified-release theophylline tablets.

      According to his mother, he returned from a trip to Pakistan last night and has been taking antibiotics for bacterial gastroenteritis for the past four days. He has three days left on his antibiotic course.

      What could be the cause of his current presentation?

      Your Answer: Ciprofloxacin

      Explanation:

      Terbinafine is frequently prescribed for the treatment of fungal nail infections as an antifungal medication.

      Theophylline and its Poisoning

      Theophylline is a naturally occurring methylxanthine that is commonly used as a bronchodilator in the management of asthma and COPD. Its exact mechanism of action is still unknown, but it is believed to be a non-specific inhibitor of phosphodiesterase, resulting in an increase in cAMP. Other proposed mechanisms include antagonism of adenosine and prostaglandin inhibition.

      However, theophylline poisoning can occur and is characterized by symptoms such as acidosis, hypokalemia, vomiting, tachycardia, arrhythmias, and seizures. In such cases, gastric lavage may be considered if the ingestion occurred less than an hour prior. Activated charcoal is also recommended, while whole-bowel irrigation can be performed if theophylline is in sustained-release form. Charcoal hemoperfusion is preferable to hemodialysis in managing theophylline poisoning.

    • This question is part of the following fields:

      • Respiratory System
      21.6
      Seconds
  • Question 18 - A 78-year-old man comes to the emergency department complaining of increasing difficulty in...

    Correct

    • A 78-year-old man comes to the emergency department complaining of increasing difficulty in breathing over the past two days. He has a medical history of squamous cell lung cancer.

      Upon examination, the trachea is observed to have shifted towards the left side, with dull percussion and absence of breath sounds throughout the left chest.

      What is the probable diagnosis?

      Your Answer: Left lung collapse

      Explanation:

      When a lung collapses, it can cause the trachea to shift towards the affected side, and there may be dullness on percussion and reduced breath sounds throughout the lung field. This is because the decrease in pressure on the affected side causes the mediastinum and trachea to move towards it.

      A massive pleural effusion, on the other hand, would cause widespread dullness and absent breath sounds, but it would push the trachea away from the affected side due to increased pressure.

      Pneumonia typically only affects one lung zone, so there would not be widespread dullness or absent breath sounds throughout the hemithorax. It also does not usually affect the position of the mediastinum or trachea.

      Pneumothorax would be hyperresonant on percussion, not dull, and it may push the trachea away from the affected side in severe cases, but this is more common in tension pneumothoraces that occur after trauma.

      A lobectomy may cause the trachea to shift towards the same side as the surgery due to decreased pressure, but it would not cause dullness or absent breath sounds throughout the lung fields.

      Understanding White Lung Lesions on Chest X-Rays

      When examining a chest x-ray, white shadowing in the lungs can indicate a variety of conditions. These may include consolidation, pleural effusion, collapse, pneumonectomy, specific lesions such as tumors, or fluid accumulation such as pulmonary edema. In cases where there is a complete white-out of one side of the chest, it is important to assess the position of the trachea. If the trachea is pulled towards the side of the white-out, it may indicate pneumonectomy, lung collapse, or pulmonary hypoplasia. If the trachea is pushed away from the white-out, it may indicate pleural effusion, a large thoracic mass, or a diaphragmatic hernia. Other signs of a positive mass effect may include leftward bowing of the azygo-oesophageal recess and splaying of the ribs on the affected side. Understanding the potential causes of white lung lesions on chest x-rays can aid in accurate diagnosis and treatment.

    • This question is part of the following fields:

      • Respiratory System
      22.6
      Seconds
  • Question 19 - A 67-year-old man visits his doctor complaining of dyspnoea. He experiences shortness of...

    Incorrect

    • A 67-year-old man visits his doctor complaining of dyspnoea. He experiences shortness of breath after walking just a few meters, whereas he can usually walk up to 200m. The man appears cyanosed in his extremities and his pulse oximeter shows a reading of 83%. What is the primary mode of carbon dioxide transportation in the bloodstream?

      Your Answer: Unbound and physically dissolved in the blood

      Correct Answer: Bound to haemoglobin as bicarbonate ions

      Explanation:

      Understanding the Oxygen Dissociation Curve

      The oxygen dissociation curve is a graphical representation of the relationship between the percentage of saturated haemoglobin and the partial pressure of oxygen in the blood. It is not influenced by the concentration of haemoglobin. The curve can shift to the left or right, indicating changes in oxygen delivery to tissues. When the curve shifts to the left, there is increased saturation of haemoglobin with oxygen, resulting in decreased oxygen delivery to tissues. Conversely, when the curve shifts to the right, there is reduced saturation of haemoglobin with oxygen, leading to enhanced oxygen delivery to tissues.

      The L rule is a helpful mnemonic to remember the factors that cause a shift to the left, resulting in lower oxygen delivery. These factors include low levels of hydrogen ions (alkali), low partial pressure of carbon dioxide, low levels of 2,3-diphosphoglycerate, and low temperature. On the other hand, the mnemonic ‘CADET, face Right!’ can be used to remember the factors that cause a shift to the right, leading to raised oxygen delivery. These factors include carbon dioxide, acid, 2,3-diphosphoglycerate, exercise, and temperature.

      Understanding the oxygen dissociation curve is crucial in assessing the oxygen-carrying capacity of the blood and the delivery of oxygen to tissues. By knowing the factors that can shift the curve to the left or right, healthcare professionals can make informed decisions in managing patients with respiratory and cardiovascular diseases.

    • This question is part of the following fields:

      • Respiratory System
      18.8
      Seconds
  • Question 20 - Which one of the following is not found in the anterior mediastinum? ...

    Incorrect

    • Which one of the following is not found in the anterior mediastinum?

      Your Answer: Arch of the azygos vein

      Correct Answer: Thoracic duct

      Explanation:

      The posterior and superior mediastinum contain the thoracic duct.

      The mediastinum is the area located between the two pulmonary cavities and is covered by the mediastinal pleura. It extends from the thoracic inlet at the top to the diaphragm at the bottom. The mediastinum is divided into four regions: the superior mediastinum, middle mediastinum, posterior mediastinum, and anterior mediastinum.

      The superior mediastinum is the area between the manubriosternal angle and T4/5. It contains important structures such as the superior vena cava, brachiocephalic veins, arch of aorta, thoracic duct, trachea, oesophagus, thymus, vagus nerve, left recurrent laryngeal nerve, and phrenic nerve. The anterior mediastinum contains thymic remnants, lymph nodes, and fat. The middle mediastinum contains the pericardium, heart, aortic root, arch of azygos vein, and main bronchi. The posterior mediastinum contains the oesophagus, thoracic aorta, azygos vein, thoracic duct, vagus nerve, sympathetic nerve trunks, and splanchnic nerves.

      In summary, the mediastinum is a crucial area in the thorax that contains many important structures and is divided into four regions. Each region contains different structures that are essential for the proper functioning of the body.

    • This question is part of the following fields:

      • Respiratory System
      5.1
      Seconds
  • Question 21 - Which one of the following does not decrease the functional residual capacity? ...

    Correct

    • Which one of the following does not decrease the functional residual capacity?

      Your Answer: Upright position

      Explanation:

      When a patient is in an upright position, the functional residual capacity (FRC) can increase due to less pressure from the diaphragm and abdominal organs on the lung bases. This increase in FRC can also be caused by emphysema and asthma. On the other hand, factors such as abdominal swelling, pulmonary edema, reduced muscle tone of the diaphragm, and aging can lead to a decrease in FRC. Additionally, laparoscopic surgery, obesity, and muscle relaxants can also contribute to a reduction in FRC.

      Understanding Lung Volumes in Respiratory Physiology

      In respiratory physiology, lung volumes can be measured to determine the amount of air that moves in and out of the lungs during breathing. The diagram above shows the different lung volumes that can be measured.

      Tidal volume (TV) refers to the amount of air that is inspired or expired with each breath at rest. In males, the TV is 500ml while in females, it is 350ml.

      Inspiratory reserve volume (IRV) is the maximum volume of air that can be inspired at the end of a normal tidal inspiration. The inspiratory capacity is the sum of TV and IRV. On the other hand, expiratory reserve volume (ERV) is the maximum volume of air that can be expired at the end of a normal tidal expiration.

      Residual volume (RV) is the volume of air that remains in the lungs after maximal expiration. It increases with age and can be calculated by subtracting ERV from FRC. Speaking of FRC, it is the volume in the lungs at the end-expiratory position and is equal to the sum of ERV and RV.

      Vital capacity (VC) is the maximum volume of air that can be expired after a maximal inspiration. It decreases with age and can be calculated by adding inspiratory capacity and ERV. Lastly, total lung capacity (TLC) is the sum of vital capacity and residual volume.

      Physiological dead space (VD) is calculated by multiplying tidal volume by the difference between arterial carbon dioxide pressure (PaCO2) and end-tidal carbon dioxide pressure (PeCO2) and then dividing the result by PaCO2.

    • This question is part of the following fields:

      • Respiratory System
      11.2
      Seconds
  • Question 22 - A 55-year-old man is admitted to the ICU after emergency surgery for an...

    Correct

    • A 55-year-old man is admitted to the ICU after emergency surgery for an abdominal aortic aneurysm. He presents with abdominal pain and diarrhea and is in a critical condition. Despite the absence of peritonism, which of the following arterial blood gas patterns is most likely to be observed?

      Your Answer: pH 7.20, pO2 9.0, pCO2 3.5, Base excess -10, Lactate 8

      Explanation:

      It is probable that this individual is experiencing metabolic acidosis as a result of a mesenteric infarction.

      Disorders of Acid-Base Balance

      The acid-base nomogram is a useful tool for categorizing the various disorders of acid-base balance. Metabolic acidosis is the most common surgical acid-base disorder, characterized by a reduction in plasma bicarbonate levels. This can be caused by a gain of strong acid or loss of base, and is classified according to the anion gap. A normal anion gap indicates hyperchloraemic metabolic acidosis, which can be caused by gastrointestinal bicarbonate loss, renal tubular acidosis, drugs, or Addison’s disease. A raised anion gap indicates lactate, ketones, urate, or acid poisoning. Metabolic alkalosis, on the other hand, is usually caused by a rise in plasma bicarbonate levels due to a loss of hydrogen ions or a gain of bicarbonate. It is mainly caused by problems of the kidney or gastrointestinal tract. Respiratory acidosis is characterized by a rise in carbon dioxide levels due to alveolar hypoventilation, while respiratory alkalosis is caused by hyperventilation resulting in excess loss of carbon dioxide. These disorders have various causes, such as COPD, sedative drugs, anxiety, hypoxia, and pregnancy.

    • This question is part of the following fields:

      • Respiratory System
      21.6
      Seconds
  • Question 23 - John, a 55-year-old man, arrives at the emergency department complaining of chest pain...

    Incorrect

    • John, a 55-year-old man, arrives at the emergency department complaining of chest pain that is relieved by leaning forward. He also mentions that the pain spreads to his left shoulder. The diagnosis is pericarditis.

      Which nerve is accountable for the referred pain in this case?

      Your Answer: Vagus nerve

      Correct Answer: Phrenic nerve

      Explanation:

      The phrenic nerve provides motor innervation to the diaphragm and sensory innervation to the pleura and pericardium. Pericarditis can cause referred pain to the shoulder due to the supraclavicular nerves originating at C3-4. It is important to note that there are no pericardial nerves. The spinal accessory nerve innervates the trapezius and sternocleidomastoid muscles, while the trochlear nerve supplies the superior oblique muscle. Although the vagus nerve has various functions, it does not supply the pericardium.

      The Phrenic Nerve: Origin, Path, and Supplies

      The phrenic nerve is a crucial nerve that originates from the cervical spinal nerves C3, C4, and C5. It supplies the diaphragm and provides sensation to the central diaphragm and pericardium. The nerve passes with the internal jugular vein across scalenus anterior and deep to the prevertebral fascia of the deep cervical fascia.

      The right phrenic nerve runs anterior to the first part of the subclavian artery in the superior mediastinum and laterally to the superior vena cava. In the middle mediastinum, it is located to the right of the pericardium and passes over the right atrium to exit the diaphragm at T8. On the other hand, the left phrenic nerve passes lateral to the left subclavian artery, aortic arch, and left ventricle. It passes anterior to the root of the lung and pierces the diaphragm alone.

      Understanding the origin, path, and supplies of the phrenic nerve is essential in diagnosing and treating conditions that affect the diaphragm and pericardium.

    • This question is part of the following fields:

      • Respiratory System
      9.2
      Seconds
  • Question 24 - During a schoolyard brawl a boy is hit in the chest. The stick...

    Correct

    • During a schoolyard brawl a boy is hit in the chest. The stick passes through the posterior mediastinum (from left to right). Which one of the following structures is least likely to be injured?

      Your Answer: Arch of the azygos vein

      Explanation:

      The azygos vein’s arch is located within the middle mediastinum.

      The mediastinum is the area located between the two pulmonary cavities and is covered by the mediastinal pleura. It extends from the thoracic inlet at the top to the diaphragm at the bottom. The mediastinum is divided into four regions: the superior mediastinum, middle mediastinum, posterior mediastinum, and anterior mediastinum.

      The superior mediastinum is the area between the manubriosternal angle and T4/5. It contains important structures such as the superior vena cava, brachiocephalic veins, arch of aorta, thoracic duct, trachea, oesophagus, thymus, vagus nerve, left recurrent laryngeal nerve, and phrenic nerve. The anterior mediastinum contains thymic remnants, lymph nodes, and fat. The middle mediastinum contains the pericardium, heart, aortic root, arch of azygos vein, and main bronchi. The posterior mediastinum contains the oesophagus, thoracic aorta, azygos vein, thoracic duct, vagus nerve, sympathetic nerve trunks, and splanchnic nerves.

      In summary, the mediastinum is a crucial area in the thorax that contains many important structures and is divided into four regions. Each region contains different structures that are essential for the proper functioning of the body.

    • This question is part of the following fields:

      • Respiratory System
      21.4
      Seconds
  • Question 25 - A 25-year-old woman presents to the Emergency department with sudden onset of difficulty...

    Incorrect

    • A 25-year-old woman presents to the Emergency department with sudden onset of difficulty breathing. She has a history of asthma but is otherwise healthy. Upon admission, she is observed to be breathing rapidly, using her accessory muscles, and is experiencing cold and clammy skin. Upon chest auscultation, widespread wheezing is detected.

      An arterial blood gas analysis reveals:

      pH 7.46
      pO2 13 kPa
      pCO2 2.7 kPa
      HCO3- 23 mmol/l

      Which aspect of the underlying disease is affected in this patient?

      Your Answer: Transfer factor

      Correct Answer: Forced Expiratory Volume

      Explanation:

      It is probable that this individual is experiencing an acute episode of asthma. Asthma is a condition that results in the constriction of the airways, known as an obstructive airway disease. Its distinguishing feature is its ability to be reversed. The forced expiratory volume is the most impacted parameter in asthma and other obstructive airway diseases.

      Understanding Lung Volumes in Respiratory Physiology

      In respiratory physiology, lung volumes can be measured to determine the amount of air that moves in and out of the lungs during breathing. The diagram above shows the different lung volumes that can be measured.

      Tidal volume (TV) refers to the amount of air that is inspired or expired with each breath at rest. In males, the TV is 500ml while in females, it is 350ml.

      Inspiratory reserve volume (IRV) is the maximum volume of air that can be inspired at the end of a normal tidal inspiration. The inspiratory capacity is the sum of TV and IRV. On the other hand, expiratory reserve volume (ERV) is the maximum volume of air that can be expired at the end of a normal tidal expiration.

      Residual volume (RV) is the volume of air that remains in the lungs after maximal expiration. It increases with age and can be calculated by subtracting ERV from FRC. Speaking of FRC, it is the volume in the lungs at the end-expiratory position and is equal to the sum of ERV and RV.

      Vital capacity (VC) is the maximum volume of air that can be expired after a maximal inspiration. It decreases with age and can be calculated by adding inspiratory capacity and ERV. Lastly, total lung capacity (TLC) is the sum of vital capacity and residual volume.

      Physiological dead space (VD) is calculated by multiplying tidal volume by the difference between arterial carbon dioxide pressure (PaCO2) and end-tidal carbon dioxide pressure (PeCO2) and then dividing the result by PaCO2.

    • This question is part of the following fields:

      • Respiratory System
      27.5
      Seconds
  • Question 26 - Which one of the following is true regarding the phrenic nerves? ...

    Correct

    • Which one of the following is true regarding the phrenic nerves?

      Your Answer: They both lie anterior to the hilum of the lungs

      Explanation:

      The phrenic nerves, located in the anterior region of the lung’s hilum, play a crucial role in keeping the diaphragm functioning properly. These nerves have both sensory and motor functions, and any issues in the sub diaphragmatic area may result in referred pain in the shoulder.

      The Phrenic Nerve: Origin, Path, and Supplies

      The phrenic nerve is a crucial nerve that originates from the cervical spinal nerves C3, C4, and C5. It supplies the diaphragm and provides sensation to the central diaphragm and pericardium. The nerve passes with the internal jugular vein across scalenus anterior and deep to the prevertebral fascia of the deep cervical fascia.

      The right phrenic nerve runs anterior to the first part of the subclavian artery in the superior mediastinum and laterally to the superior vena cava. In the middle mediastinum, it is located to the right of the pericardium and passes over the right atrium to exit the diaphragm at T8. On the other hand, the left phrenic nerve passes lateral to the left subclavian artery, aortic arch, and left ventricle. It passes anterior to the root of the lung and pierces the diaphragm alone.

      Understanding the origin, path, and supplies of the phrenic nerve is essential in diagnosing and treating conditions that affect the diaphragm and pericardium.

    • This question is part of the following fields:

      • Respiratory System
      10.8
      Seconds
  • Question 27 - A 36-year-old male patient complains of fever, malaise, weight loss, dyspnoea, and shoulder...

    Correct

    • A 36-year-old male patient complains of fever, malaise, weight loss, dyspnoea, and shoulder & hip joint pain. He has raised erythematous lesions on both legs. His blood tests reveal elevated calcium levels and serum ACE levels. A chest x-ray shows bilateral hilar lymphadenopathy.

      What is the probable diagnosis?

      Your Answer: Sarcoidosis

      Explanation:

      If a patient presents with raised serum ACE levels, sarcoidosis should be considered as a possible diagnosis. The combination of erythema nodosum and bilateral hilar lymphadenopathy on a chest x-ray is pathognomonic of sarcoidosis. Lung cancer is unlikely in a young patient without a significant smoking history, and tuberculosis would require recent foreign travel to a TB endemic country. Multiple myeloma would not cause the same symptoms as sarcoidosis. Exposure to organic material would not be a likely cause of raised serum ACE levels.

      Understanding Sarcoidosis: A Multisystem Disorder

      Sarcoidosis is a condition that affects multiple systems in the body and is characterized by the presence of non-caseating granulomas. The exact cause of this disorder is unknown, but it is more commonly seen in young adults and individuals of African descent.

      The symptoms of sarcoidosis can vary depending on the severity of the condition. Acute symptoms may include erythema nodosum, bilateral hilar lymphadenopathy, swinging fever, and polyarthralgia. On the other hand, insidious symptoms may include dyspnea, non-productive cough, malaise, and weight loss. Additionally, some individuals may develop skin symptoms such as lupus pernio, while others may experience hypercalcemia due to increased conversion of vitamin D to its active form.

      Sarcoidosis is also associated with several syndromes, including Lofgren’s syndrome, Mikulicz syndrome, and Heerfordt’s syndrome. Lofgren’s syndrome is an acute form of the disease that typically presents with bilateral hilar lymphadenopathy, erythema nodosum, fever, and polyarthralgia. Mikulicz syndrome is characterized by enlargement of the parotid and lacrimal glands due to sarcoidosis, tuberculosis, or lymphoma. Finally, Heerfordt’s syndrome, also known as uveoparotid fever, presents with parotid enlargement, fever, and uveitis secondary to sarcoidosis.

      In conclusion, sarcoidosis is a complex disorder that can affect multiple systems in the body. While the exact cause is unknown, early diagnosis and treatment can help manage symptoms and improve outcomes.

    • This question is part of the following fields:

      • Respiratory System
      17.1
      Seconds
  • Question 28 - A 20-year-old male arrives at the emergency department with a sudden worsening of...

    Correct

    • A 20-year-old male arrives at the emergency department with a sudden worsening of his asthma symptoms. He is experiencing difficulty in speaking and breathing, with cyanosis of the lips and a respiratory rate of 33 breaths per minute. He reports feeling lightheaded. Although his airways are open, his chest sounds are faint upon auscultation. The patient is administered oxygen, nebulized salbutamol, and intravenous aminophylline.

      What is the mechanism of action of aminophylline?

      Your Answer: Binds to adenosine receptors and blocks adenosine-mediated bronchoconstriction

      Explanation:

      Aminophylline works by binding to adenosine receptors and preventing adenosine-induced bronchoconstriction. This mode of action is different from antihistamines like loratadine, which is an incorrect option. Theophylline, a shorter acting form of aminophylline, competitively inhibits type III and type IV phosphodiesterase enzymes responsible for breaking down cyclic AMP in smooth muscle cells, leading to possible bronchodilation. Additionally, theophylline binds to the adenosine A2B receptor and blocks adenosine-mediated bronchoconstriction. In inflammatory conditions, theophylline activates histone deacetylase, which prevents the transcription of inflammatory genes that require histone acetylation for transcription to begin. Therefore, the last three options are incorrect. (Source: Drugbank)

      Aminophylline infusions are utilized to manage acute asthma and COPD. In patients who have not received xanthines (theophylline or aminophylline) before, a loading dose of 5 mg/kg is administered through a slow intravenous injection lasting at least 20 minutes. For the maintenance infusion, 1g of aminophylline is mixed with 1 litre of normal saline to create a solution of 1 mg/ml. The recommended dose is 500-700 mcg/kg/hour, or 300 mcg/kg/hour for elderly patients. It is important to monitor plasma theophylline concentrations.

    • This question is part of the following fields:

      • Respiratory System
      26.1
      Seconds
  • Question 29 - A 28-year-old female patient presents to your clinic seeking help to quit smoking....

    Incorrect

    • A 28-year-old female patient presents to your clinic seeking help to quit smoking. Despite several attempts in the past, she has been unsuccessful. She has a medical history of bipolar disorder and well-managed epilepsy, for which she takes lamotrigine. She currently smokes 15 cigarettes per day and is especially interested in the health benefits of quitting smoking since she has recently found out that she is pregnant. As her physician, you decide to prescribe a suitable medication to assist her in her efforts. What would be the most appropriate treatment option?

      Your Answer: Bupropion

      Correct Answer: Nicotine gum

      Explanation:

      Standard treatments for nicotine dependence do not include amitriptyline, fluoxetine, or gabapentin. Nicotine replacement therapy (NRT) can be helpful for motivated patients, but it is not a cure for addiction and may require multiple attempts. Bupropion and varenicline are other smoking cessation aids, but they have multiple side effects and may not be suitable for all patients. NICE guidelines recommend discussing the best method of smoking cessation with the patient, but NRT is considered safer in pregnancy.

    • This question is part of the following fields:

      • Respiratory System
      6.4
      Seconds
  • Question 30 - A 15-year-old girl presents with difficulty breathing and is unable to speak in...

    Incorrect

    • A 15-year-old girl presents with difficulty breathing and is unable to speak in full sentences due to panic. She has a history of asthma. Upon examination, her respiratory rate is 28 breaths/minute, heart rate is 105 beats/minute, and her chest is silent. What is the most concerning feature in this girl's history?

      Your Answer: Unable to talk in full sentences

      Correct Answer: Silent chest

      Explanation:

      Identify the life-threatening features of an asthma attack.

      Assessing the severity of asthma attacks in children is crucial for effective management. The 2016 BTS/SIGN guidelines provide criteria for assessing the severity of asthma in general practice. These criteria include measuring SpO2 levels, PEF (peak expiratory flow) rates, heart rate, respiratory rate, use of accessory neck muscles, and other symptoms such as breathlessness, agitation, altered consciousness, and cyanosis.

      A severe asthma attack is characterized by a SpO2 level below 92%, PEF rates between 33-50% of the best or predicted, being too breathless to talk or feed, and a high heart and respiratory rate. On the other hand, a life-threatening asthma attack is indicated by a SpO2 level below 92%, PEF rates below 33% of the best or predicted, a silent chest, poor respiratory effort, use of accessory neck muscles, agitation, altered consciousness, and cyanosis.

      It is important for healthcare professionals to be familiar with these criteria to ensure prompt and appropriate management of asthma attacks in children. Early recognition of the severity of an asthma attack can help prevent complications and reduce the risk of hospitalization or death.

    • This question is part of the following fields:

      • Respiratory System
      19.9
      Seconds
  • Question 31 - A 12-year-old girl is referred to a respiratory specialist due to persistent episodes...

    Incorrect

    • A 12-year-old girl is referred to a respiratory specialist due to persistent episodes of shortness of breath. She also suffers from severe hay fever and eczema. After undergoing a peak expiratory flow test, signs of outflow obstruction of her lungs are detected. The doctor prescribes beclomethasone and salbutamol for her and advises her mother to keep her away from dust, as asthma is often linked to hypersensitivity to dust. Which type of hypersensitivity is associated with asthma?

      Your Answer: Type 2 hypersensitivity

      Correct Answer: Type 1 hypersensitivity

      Explanation:

      Asthma is linked to type 1 hypersensitivity, which is caused by the binding of IgE to Mast cells, resulting in an inflammatory reaction. Other types of hypersensitivity include type 2, which involves the binding of IgG or IgM to cell surface antigens, type 3, which is immune complex-mediated, and type 4, which is T-cell mediated.

      Asthma is a common respiratory disorder that affects both children and adults. It is characterized by chronic inflammation of the airways, resulting in reversible bronchospasm and airway obstruction. While asthma can develop at any age, it typically presents in childhood and may improve or resolve with age. However, it can also persist into adulthood and cause significant morbidity, with around 1,000 deaths per year in the UK.

      Several risk factors can increase the likelihood of developing asthma, including a personal or family history of atopy, antenatal factors such as maternal smoking or viral infections, low birth weight, not being breastfed, exposure to allergens and air pollution, and the hygiene hypothesis. Patients with asthma may also suffer from other atopic conditions such as eczema and hay fever, and some may be sensitive to aspirin. Occupational asthma is also a concern for those exposed to allergens in the workplace.

      Symptoms of asthma include coughing, dyspnea, wheezing, and chest tightness, with coughing often worse at night. Signs may include expiratory wheezing on auscultation and reduced peak expiratory flow rate. Diagnosis is typically made through spirometry, which measures the volume and speed of air during exhalation and inhalation.

      Management of asthma typically involves the use of inhalers to deliver drug therapy directly to the airways. Short-acting beta-agonists such as salbutamol are the first-line treatment for relieving symptoms, while inhaled corticosteroids like beclometasone dipropionate and fluticasone propionate are used for daily maintenance therapy. Long-acting beta-agonists like salmeterol and leukotriene receptor antagonists like montelukast may also be used in combination with other medications. Maintenance and reliever therapy (MART) is a newer approach that combines ICS and a fast-acting LABA in a single inhaler for both daily maintenance and symptom relief. Recent guidelines recommend offering a leukotriene receptor antagonist instead of a LABA for patients on SABA + ICS whose asthma is not well controlled, and considering MART for those with poorly controlled asthma.

    • This question is part of the following fields:

      • Respiratory System
      23.1
      Seconds
  • Question 32 - A 65-year-old man with a 45-pack-year history arrives at the hospital complaining of...

    Correct

    • A 65-year-old man with a 45-pack-year history arrives at the hospital complaining of increased difficulty breathing and cachexia. Upon examination, a chest X-ray reveals an elevated left hemidiaphragm, enlarged hilar lymph nodes, and a significant opacification. Which structure is most likely to have been affected?

      Your Answer: Left phrenic nerve

      Explanation:

      It is unlikely that direct injury would result in the elevation of the left hemidiaphragm, especially since there is no history of trauma or surgery. However, damage to the long thoracic nerve could cause winging of the scapula due to weakened serratus anterior muscle. On the other hand, injury to the thoracodorsal nerve, which innervates the latissimus dorsi muscle, can lead to weakened shoulder adduction and is a common complication of axillary surgery.

      The Phrenic Nerve: Origin, Path, and Supplies

      The phrenic nerve is a crucial nerve that originates from the cervical spinal nerves C3, C4, and C5. It supplies the diaphragm and provides sensation to the central diaphragm and pericardium. The nerve passes with the internal jugular vein across scalenus anterior and deep to the prevertebral fascia of the deep cervical fascia.

      The right phrenic nerve runs anterior to the first part of the subclavian artery in the superior mediastinum and laterally to the superior vena cava. In the middle mediastinum, it is located to the right of the pericardium and passes over the right atrium to exit the diaphragm at T8. On the other hand, the left phrenic nerve passes lateral to the left subclavian artery, aortic arch, and left ventricle. It passes anterior to the root of the lung and pierces the diaphragm alone.

      Understanding the origin, path, and supplies of the phrenic nerve is essential in diagnosing and treating conditions that affect the diaphragm and pericardium.

    • This question is part of the following fields:

      • Respiratory System
      31.3
      Seconds
  • Question 33 - A father brings his 5-year-old daughter to the GP with a 72-hour history...

    Incorrect

    • A father brings his 5-year-old daughter to the GP with a 72-hour history of left ear pain. She has had a cough with coryzal symptoms for the past four days. She has no past medical history, allergies or current medications, and she is up-to-date with her vaccinations. Her temperature is 38.5ºC. No abnormality is detected on examination of the oral cavity. Following otoscopy, what is the most likely causative pathogen for her diagnosis of otitis media?

      Your Answer: Rhinovirus

      Correct Answer: Streptococcus pneumoniae

      Explanation:

      Otitis media is primarily caused by bacteria, with viral URTIs often preceding the infection. The majority of cases are secondary to bacterial infections, with the most common culprit being…

      Acute otitis media is a common condition in young children, often caused by bacterial infections following viral upper respiratory tract infections. Symptoms include ear pain, fever, and hearing loss, and diagnosis is based on criteria such as the presence of a middle ear effusion and inflammation of the tympanic membrane. Antibiotics may be prescribed in certain cases, and complications can include perforation of the tympanic membrane, hearing loss, and more serious conditions such as meningitis and brain abscess.

    • This question is part of the following fields:

      • Respiratory System
      19.1
      Seconds
  • Question 34 - A 24-year-old male patient arrives at the Emergency Department complaining of abdominal pain,...

    Correct

    • A 24-year-old male patient arrives at the Emergency Department complaining of abdominal pain, nausea, vomiting, and a decreased level of consciousness. Upon examination, the patient exhibits Kussmaul respiration and an acetone-like breath odor.

      What type of metabolic disturbance is most consistent with the symptoms and presentation of this patient?

      Your Answer: Metabolic acidosis, oxygen dissociation curve shifts to the right

      Explanation:

      The correct answer is that metabolic acidosis shifts the oxygen dissociation curve to the right. This is seen in the condition described in the question, diabetic ketoacidosis, which is associated with metabolic acidosis. Acidosis causes more oxygen to be unloaded from haemoglobin, leading to a rightward shift in the curve. The other answer options are incorrect, as they either describe a different type of acidosis or an incorrect direction of the curve shift.

      Understanding the Oxygen Dissociation Curve

      The oxygen dissociation curve is a graphical representation of the relationship between the percentage of saturated haemoglobin and the partial pressure of oxygen in the blood. It is not influenced by the concentration of haemoglobin. The curve can shift to the left or right, indicating changes in oxygen delivery to tissues. When the curve shifts to the left, there is increased saturation of haemoglobin with oxygen, resulting in decreased oxygen delivery to tissues. Conversely, when the curve shifts to the right, there is reduced saturation of haemoglobin with oxygen, leading to enhanced oxygen delivery to tissues.

      The L rule is a helpful mnemonic to remember the factors that cause a shift to the left, resulting in lower oxygen delivery. These factors include low levels of hydrogen ions (alkali), low partial pressure of carbon dioxide, low levels of 2,3-diphosphoglycerate, and low temperature. On the other hand, the mnemonic ‘CADET, face Right!’ can be used to remember the factors that cause a shift to the right, leading to raised oxygen delivery. These factors include carbon dioxide, acid, 2,3-diphosphoglycerate, exercise, and temperature.

      Understanding the oxygen dissociation curve is crucial in assessing the oxygen-carrying capacity of the blood and the delivery of oxygen to tissues. By knowing the factors that can shift the curve to the left or right, healthcare professionals can make informed decisions in managing patients with respiratory and cardiovascular diseases.

    • This question is part of the following fields:

      • Respiratory System
      18.5
      Seconds
  • Question 35 - A 35-year-old pregnant woman undergoes an ABG test. What is the anticipated outcome...

    Incorrect

    • A 35-year-old pregnant woman undergoes an ABG test. What is the anticipated outcome for a healthy pregnant woman?

      Your Answer: Normal

      Correct Answer: Compensated respiratory alkalosis

      Explanation:

      During pregnancy, a woman’s increased tidal volume leads to a decrease in carbon dioxide levels, resulting in alkalosis. This is because carbon dioxide generates acid, and reduced levels of it lead to a decrease in acid. The kidneys eventually adapt to this change by reducing the amount of alkaline bicarbonate in the body. Therefore, pregnancy causes a compensated respiratory alkalosis.

      If a woman’s bicarbonate levels remain normal, she would have simple respiratory alkalosis.

      On the other hand, if a woman produces excess acid, she would have metabolic acidosis, which is the opposite of what occurs during pregnancy.

      Arterial Blood Gas Interpretation: A 5-Step Approach

      Arterial blood gas interpretation is a crucial aspect of patient care, particularly in critical care settings. The Resuscitation Council (UK) recommends a 5-step approach to interpreting arterial blood gas results. The first step is to assess the patient’s overall condition. The second step is to determine if the patient is hypoxaemic, with a PaO2 on air of less than 10 kPa. The third step is to assess if the patient is acidaemic (pH <7.35) or alkalaemic (pH >7.45).

      The fourth step is to evaluate the respiratory component of the arterial blood gas results. A PaCO2 level greater than 6.0 kPa suggests respiratory acidosis, while a PaCO2 level less than 4.7 kPa suggests respiratory alkalosis. The fifth step is to assess the metabolic component of the arterial blood gas results. A bicarbonate level less than 22 mmol/l or a base excess less than -2mmol/l suggests metabolic acidosis, while a bicarbonate level greater than 26 mmol/l or a base excess greater than +2mmol/l suggests metabolic alkalosis.

      To remember the relationship between pH, PaCO2, and bicarbonate, the acronym ROME can be used. Respiratory acidosis or alkalosis is opposite to the pH level, while metabolic acidosis or alkalosis is equal to the pH level. This 5-step approach and the ROME acronym can aid healthcare professionals in interpreting arterial blood gas results accurately and efficiently.

    • This question is part of the following fields:

      • Respiratory System
      6.6
      Seconds
  • Question 36 - A 35-year-old woman presents with sudden chest pain and difficulty breathing. She recently...

    Correct

    • A 35-year-old woman presents with sudden chest pain and difficulty breathing. She recently returned from a trip to Italy with her family. She has no significant medical history but takes oral contraceptives. On examination, her pulse is 100 bpm, temperature is 37°C, oxygen saturation is 95%, respiratory rate is 28/min, and blood pressure is 116/76 mmHg. Chest examination is unremarkable and chest x-ray is normal. What is the most appropriate diagnostic test to confirm the diagnosis?

      Your Answer: CT pulmonary angiogram (CTPA)

      Explanation:

      Diagnosis of Pulmonary Embolism in a Woman with Chest Pain and Dyspnoea

      This woman is experiencing chest pain and difficulty breathing, with a rapid heart rate and breathing rate. However, there are no visible signs on chest examination and her chest x-ray appears normal. Despite having no fever, her oxygen levels are lower than expected for a healthy person. To rule out a pulmonary embolism, doctors must consider risk factors such as recent air travel and use of oral contraceptives.

      The gold standard for diagnosing a pulmonary embolism is a CT pulmonary angiogram, as it can detect even large saddle embolus near the pulmonary arteries. While VQ scanning was previously used, it can miss these larger emboli. Additionally, doctors may perform Doppler ultrasounds of the venous system to check for deep vein thrombosis.

      This presentation is not indicative of atypical pneumonia, such as Legionella, as the patient’s temperature would be expected to be high and chest signs would be present. Overall, a thorough evaluation is necessary to accurately diagnose and treat a pulmonary embolism in a patient with chest pain and dyspnoea.

    • This question is part of the following fields:

      • Respiratory System
      25.8
      Seconds
  • Question 37 - A 65-year-old male with a history of chronic obstructive pulmonary disease (COPD) has...

    Correct

    • A 65-year-old male with a history of chronic obstructive pulmonary disease (COPD) has been admitted and treated for infective exacerbations of COPD three times in the past year. Despite his respiratory issues, he continues to smoke. He is currently receiving only short-acting beta2-agonist therapy. During his COPD patient review with the nurse practitioner at his local general practice, spirometry results reveal a drop in his FEV1 from 65% to 58%.

      What is the most effective approach to manage his condition and prevent further decline in his FEV1?

      Your Answer: Smoking cessation

      Explanation:

      The most effective intervention to slow the decrease in FEV1 experienced by patients with COPD is to stop smoking. If the patient has no asthmatic/steroid-responsive features, the next step in management would be to add a long-acting beta2-agonist (LABA) and a long-acting muscarinic antagonist. If the patient has asthmatic/steroid-responsive features, the next step would be to add a LABA and an inhaled corticosteroid. Oral theophylline is only considered if inhaled therapy is not possible, and oral prednisolone is only used during acute infective exacerbations of COPD to help with inflammation and is not a long-term solution to slow the reduction of FEV1.

      The National Institute for Health and Care Excellence (NICE) updated its guidelines on the management of chronic obstructive pulmonary disease (COPD) in 2018. The guidelines recommend general management strategies such as smoking cessation advice, annual influenzae vaccination, and one-off pneumococcal vaccination. Pulmonary rehabilitation is also recommended for patients who view themselves as functionally disabled by COPD.

      Bronchodilator therapy is the first-line treatment for patients who remain breathless or have exacerbations despite using short-acting bronchodilators. The next step is determined by whether the patient has asthmatic features or features suggesting steroid responsiveness. NICE suggests several criteria to determine this, including a previous diagnosis of asthma or atopy, a higher blood eosinophil count, substantial variation in FEV1 over time, and substantial diurnal variation in peak expiratory flow.

      If the patient does not have asthmatic features or features suggesting steroid responsiveness, a long-acting beta2-agonist (LABA) and long-acting muscarinic antagonist (LAMA) should be added. If the patient is already taking a short-acting muscarinic antagonist (SAMA), it should be discontinued and switched to a short-acting beta2-agonist (SABA). If the patient has asthmatic features or features suggesting steroid responsiveness, a LABA and inhaled corticosteroid (ICS) should be added. If the patient remains breathless or has exacerbations, triple therapy (LAMA + LABA + ICS) should be offered.

      NICE only recommends theophylline after trials of short and long-acting bronchodilators or to people who cannot use inhaled therapy. Azithromycin prophylaxis is recommended in select patients who have optimised standard treatments and continue to have exacerbations. Mucolytics should be considered in patients with a chronic productive cough and continued if symptoms improve.

      Cor pulmonale features include peripheral oedema, raised jugular venous pressure, systolic parasternal heave, and loud P2. Loop diuretics should be used for oedema, and long-term oxygen therapy should be considered. Smoking cessation, long-term oxygen therapy in eligible patients, and lung volume reduction surgery in selected patients may improve survival in patients with stable COPD. NICE does not recommend the use of ACE-inhibitors, calcium channel blockers, or alpha blockers

    • This question is part of the following fields:

      • Respiratory System
      10.7
      Seconds
  • Question 38 - A 56-year-old man has been diagnosed with small cell lung carcinoma. The tumor...

    Correct

    • A 56-year-old man has been diagnosed with small cell lung carcinoma. The tumor measures 4 centimeters in its largest dimension and is not invading any surrounding structures. However, there are metastases in the ipsilateral hilar lymph nodes, and no distant metastases have been found. What is the TNM score for this patient, considering the primary tumor (T), regional lymph nodes (N), and distant metastases (M)?

      Your Answer: T2 N1 M0

      Explanation:

      It is crucial to have knowledge about the TNM system for staging lung cancer. The absence of distant metastases eliminates one of the options immediately (as M must be 0).

      The size and invasion of the tumor are significant factors:
      – T1 is less than 3 cm
      – T2 is between 3 cm and 7 cm
      – T3 is more than 7 cm and/or involves invasion of the chest wall, parietal pleura, diaphragm, phrenic nerve, mediastinal pleura, or parietal pericardium
      – T4 can be any size but involves invasion of other structures

      To differentiate between N1 and N2, remember that N1 involves ipsilateral hilar or peribronchial lymph nodes, while N2 involves ipsilateral mediastinal and/or subcarinal lymph nodes.

      Small Cell Lung Cancer: Characteristics and Management

      Small cell lung cancer is a type of lung cancer that usually develops in the central part of the lungs and arises from APUD cells. This type of cancer is often associated with the secretion of hormones such as ADH and ACTH, which can cause hyponatremia and Cushing’s syndrome, respectively. In addition, ACTH secretion can lead to bilateral adrenal hyperplasia and hypokalemic alkalosis due to high levels of cortisol. Patients with small cell lung cancer may also experience Lambert-Eaton syndrome, which is characterized by antibodies to voltage-gated calcium channels causing a myasthenic-like syndrome.

      Management of small cell lung cancer depends on the stage of the disease. Patients with very early stage disease may be considered for surgery, while those with limited disease typically receive a combination of chemotherapy and radiotherapy. Patients with more extensive disease are offered palliative chemotherapy. Unfortunately, most patients with small cell lung cancer are diagnosed with metastatic disease, making treatment more challenging.

      Overall, small cell lung cancer is a complex disease that requires careful management and monitoring. Early detection and treatment can improve outcomes, but more research is needed to better understand the underlying mechanisms of this type of cancer.

    • This question is part of the following fields:

      • Respiratory System
      32.5
      Seconds
  • Question 39 - Which of the following muscles is not innervated by the ansa cervicalis? ...

    Incorrect

    • Which of the following muscles is not innervated by the ansa cervicalis?

      Your Answer: Omohyoid

      Correct Answer: Mylohyoid

      Explanation:

      The muscles of the ansa cervicalis are: GenioHyoid, ThyroidHyoid, Superior Omohyoid, SternoThyroid, SternoHyoid, and Inferior Omohyoid. The mylohyoid muscle is innervated by the mylohyoid branch of the inferior alveolar nerve. A mnemonic to remember these muscles is GHost THought SOmeone Stupid Shot Irene.

      The ansa cervicalis is a nerve that provides innervation to the sternohyoid, sternothyroid, and omohyoid muscles. It is composed of two roots: the superior root, which branches off from C1 and is located anterolateral to the carotid sheath, and the inferior root, which is derived from the C2 and C3 roots and passes posterolateral to the internal jugular vein. The inferior root enters the inferior aspect of the strap muscles, which are located in the neck, and should be divided in their upper half when exposing a large goitre. The ansa cervicalis is situated in front of the carotid sheath and is an important nerve for the proper functioning of the neck muscles.

    • This question is part of the following fields:

      • Respiratory System
      14
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Respiratory System (17/39) 44%
Passmed