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Question 1
Incorrect
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A patient presents with a history of feeling constantly thirsty and urinating large amounts. She also experiences extreme fatigue. A diagnosis of diabetes mellitus is suspected, and a fasting blood glucose sample is scheduled.
What is the current WHO threshold for diagnosing diabetes mellitus using a fasting blood sample in this case?Your Answer: 10 mmol/l
Correct Answer: 7 mmol/l
Explanation:According to the 2011 recommendations from the World Health Organization (WHO), the following criteria are used to diagnose diabetes mellitus:
– A random venous plasma glucose concentration that exceeds 11.1 mmol/l.
– A fasting plasma glucose concentration that is higher than 7.0 mmol/l.
– A two-hour plasma glucose concentration that exceeds 11.1 mmol/l, measured two hours after consuming 75g of anhydrous glucose during an oral glucose tolerance test (OGTT).
– An HbA1c level that is greater than 48 mmol/mol (equivalent to 6.5%).These guidelines provide specific thresholds for diagnosing diabetes mellitus based on various glucose measurements and HbA1c levels. It is important for healthcare professionals to consider these criteria when evaluating individuals for diabetes mellitus.
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This question is part of the following fields:
- Endocrinology
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Question 2
Correct
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A 68 year old female is brought into the emergency department by family members after complaining of chest discomfort while having a glass of wine with them at home. During triage, the patient suddenly loses consciousness and becomes non-responsive. The triage nurse immediately calls for assistance and starts performing CPR. Upon your arrival, you connect the defibrillator leads and briefly pause CPR to assess the heart rhythm. Which of the following cardiac rhythms can be treated with defibrillation?
Your Answer: Ventricular fibrillation
Explanation:Defibrillation is a procedure used to treat two specific cardiac rhythms, ventricular fibrillation and pulseless ventricular tachycardia. It involves delivering an electrical shock randomly during the cardiac cycle to restore a normal heart rhythm. It is important to note that defibrillation is different from cardioversion, which involves delivering energy synchronized to the QRS complex.
Further Reading:
In the event of an adult experiencing cardiorespiratory arrest, it is crucial for doctors to be familiar with the Advanced Life Support (ALS) algorithm. They should also be knowledgeable about the proper technique for chest compressions, the appropriate rhythms for defibrillation, the reversible causes of arrest, and the drugs used in advanced life support.
During chest compressions, the rate should be between 100-120 compressions per minute, with a depth of compression of 5-6 cm. The ratio of chest compressions to rescue breaths should be 30:2. It is important to change the person giving compressions regularly to prevent fatigue.
There are two shockable ECG rhythms that doctors should be aware of: ventricular fibrillation (VF) and pulseless ventricular tachycardia (pVT). These rhythms require defibrillation.
There are four reversible causes of cardiorespiratory arrest, known as the 4 H’s and 4 T’s. The 4 H’s include hypoxia, hypovolemia, hypo or hyperkalemia or metabolic abnormalities, and hypothermia. The 4 T’s include thrombosis (coronary or pulmonary), tension pneumothorax, tamponade, and toxins. Identifying and treating these reversible causes is crucial for successful resuscitation.
When it comes to resus drugs, they are considered of secondary importance during CPR due to the lack of high-quality evidence for their efficacy. However, adrenaline (epinephrine) and amiodarone are the two drugs included in the ALS algorithm. Doctors should be familiar with the dosing, route, and timing of administration for both drugs.
Adrenaline should be administered intravenously at a concentration of 1 in 10,000 (100 micrograms/mL). It should be repeated every 3-5 minutes. Amiodarone is initially given at a dose of 300 mg, either from a pre-filled syringe or diluted in 20 mL of Glucose 5%. If required, an additional dose of 150 mg can be given by intravenous injection. This is followed by an intravenous infusion of 900 mg over 24 hours. The first dose of amiodarone is given after 3 shocks.
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This question is part of the following fields:
- Resus
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Question 3
Correct
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A 6-week-old baby girl presents with a low-grade fever, feeding difficulties, and a persistent cough that have been present for the past three days. You suspect bronchiolitis as the diagnosis.
What is the MOST likely causative organism in this case?Your Answer: Respiratory syncytial virus
Explanation:Bronchiolitis is a common respiratory infection that primarily affects infants. It typically occurs between the ages of 3-6 months and is most prevalent during the winter months from November to March. The main culprit behind bronchiolitis is the respiratory syncytial virus, accounting for about 70% of cases. However, other viruses like parainfluenza, influenza, adenovirus, coronavirus, and rhinovirus can also cause this infection.
The clinical presentation of bronchiolitis usually starts with symptoms resembling a common cold, which last for the first 2-3 days. Infants may experience poor feeding, rapid breathing (tachypnoea), nasal flaring, and grunting. Chest wall recessions, bilateral fine crepitations, and wheezing may also be observed. In severe cases, apnoea, a temporary cessation of breathing, can occur.
Bronchiolitis is a self-limiting illness, meaning it resolves on its own over time. Therefore, treatment mainly focuses on supportive care. However, infants with oxygen saturations below 92% may require oxygen administration. If an infant is unable to maintain oral intake or hydration, nasogastric feeding should be considered. Nasal suction is recommended to clear secretions in infants experiencing respiratory distress due to nasal blockage.
It is important to note that there is no evidence supporting the use of antivirals (such as ribavirin), antibiotics, beta 2 agonists, anticholinergics, or corticosteroids in the management of bronchiolitis. These interventions are not recommended for this condition.
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This question is part of the following fields:
- Respiratory
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Question 4
Incorrect
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A middle-aged man presents with visual difficulties. Upon examination, it is discovered that he has a quadrantic visual field defect. He is subsequently taken to the hospital for a CT head scan, which confirms a diagnosis of a cerebrovascular accident.
Which of the following blood vessels is most likely to be impacted?Your Answer: Posterior inferior cerebellar artery
Correct Answer: Posterior cerebral artery
Explanation:The symptoms and signs of strokes can vary depending on which blood vessel is affected. Here is a summary of the main symptoms based on the territory affected:
Anterior cerebral artery: This can cause weakness on the opposite side of the body, with the leg and shoulder being more affected than the arm, hand, and face. There may also be minimal loss of sensation on the opposite side of the body. Other symptoms can include difficulty speaking (dysarthria), language problems (aphasia), apraxia (difficulty with limb movements), urinary incontinence, and changes in behavior and personality.
Middle cerebral artery: This can lead to weakness on the opposite side of the body, with the face and arm being more affected than the leg. There may also be a loss of sensation on the opposite side of the body. Depending on the dominant hemisphere of the brain, there may be difficulties with expressive or receptive language (dysphasia). In the non-dominant hemisphere, there may be neglect of the opposite side of the body.
Posterior cerebral artery: This can cause a loss of vision on the opposite side of both eyes (homonymous hemianopia). There may also be defects in a specific quadrant of the visual field. In some cases, there may be a syndrome affecting the thalamus on the opposite side of the body.
It’s important to note that these are just general summaries and individual cases may vary. If you suspect a stroke, it’s crucial to seek immediate medical attention.
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This question is part of the following fields:
- Neurology
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Question 5
Incorrect
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A 4-year-old girl presents with stridor and a barking cough. Her mother reports that she has had a slight cold for a few days and her voice had been hoarse. Her vital signs are as follows: temperature 38.1°C, heart rate 135, respiratory rate 30, oxygen saturation 97% on room air. Her chest examination is unremarkable, but you observe the presence of stridor at rest.
What is the SINGLE most probable causative organism?Your Answer:
Correct Answer: Parainfluenza virus
Explanation:Croup, also known as laryngo-tracheo-bronchitis, is typically caused by the parainfluenza virus. Other viruses such as rhinovirus, influenza, and respiratory syncytial viruses can also be responsible. Before the onset of stridor, there is often a mild cold-like illness that lasts for 1-2 days. Symptoms usually reach their peak within 1-3 days, with the cough often being more troublesome at night. A milder cough may persist for another 7-10 days.
A distinctive feature of croup is a barking cough, but it does not indicate the severity of the condition. To reduce airway swelling, dexamethasone and prednisolone are commonly prescribed. If a child is experiencing vomiting, nebulized budesonide can be used as an alternative. However, it is important to note that steroids do not shorten the duration of the illness. In severe cases, nebulized adrenaline can be administered.
Hospitalization for croup is uncommon and typically reserved for children who are experiencing worsening respiratory distress or showing signs of drowsiness or agitation.
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This question is part of the following fields:
- Respiratory
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Question 6
Incorrect
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A 30-year-old woman is brought in by ambulance following a car accident where her car was struck by a truck. She has suffered severe facial injuries and shows signs of airway obstruction. Her C-spine is triple immobilized. You perform a LEMON assessment for difficult intubation.
Which of the following factors indicates a difficult intubation?Your Answer:
Correct Answer: Mallampati score of 4
Explanation:Trauma patients who require a definitively secured airway include those who are apnoeic, have a Glasgow Coma Scale score of less than 9, experience sustained seizure activity, have unstable midface trauma or airway injuries, have a large flail segment or respiratory failure, have a high risk of aspiration, or are unable to maintain an airway or oxygenation through other means.
To predict difficult intubations, the LEMON assessment can be utilized. The LEMON mnemonic provides a systematic approach to assess potential challenges in intubation. It stands for the following:
– Look externally: Examine for any characteristics that are known to cause difficult intubation or ventilation.
– Evaluate the 3-3-2 rule: Measure the incisor distance, hyoid/mental distance, and thyroid-to-mouth distance. If any of these measurements are less than the specified number of fingerbreadths, it may indicate a difficult intubation.
– Mallampati: Assess the Mallampati score, which is a classification system based on the visibility of certain structures in the mouth and throat. A score of 3 or higher suggests a difficult intubation.
– Obstruction: Check for the presence of any conditions that could potentially obstruct the airway.
– Neck mobility: Evaluate the mobility of the patient’s neck, as limited mobility may make intubation more challenging.By utilizing the LEMON assessment, healthcare providers can identify potential difficulties in securing the airway and make appropriate interventions to ensure patient safety.
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This question is part of the following fields:
- Basic Anaesthetics
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Question 7
Incorrect
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A 42-year-old man has been brought into the Emergency Department, experiencing seizures that have lasted for 40 minutes before his arrival. On arrival, he is still having a tonic-clonic seizure. He is a known epileptic and is currently taking lamotrigine for seizure prevention. He has received a single dose of rectal diazepam by the paramedics en route approximately 15 minutes ago. His vital signs are as follows: HR 92, BP 120/70, SaO2 98% on high flow oxygen, temperature is 36.8°C. His blood glucose level is 4.5 mmol/L, and he has an intravenous line in place.
Which of the following medications would be most appropriate to administer next?Your Answer:
Correct Answer: Intravenous lorazepam
Explanation:Status epilepticus is a condition characterized by continuous seizure activity lasting for 5 minutes or more without the return of consciousness, or recurrent seizures (2 or more) without a period of neurological recovery in between. In such cases, the next step in managing the patient would be to administer a second dose of benzodiazepine. Since the patient already has an intravenous line in place, this would be the most appropriate route to choose.
The management of status epilepticus involves several general measures, which are outlined in the following table:
1st stage (Early status, 0-10 minutes):
– Secure the airway and provide resuscitation
– Administer oxygen
– Assess cardiorespiratory function
– Establish intravenous access2nd stage (0-30 minutes):
– Institute regular monitoring
– Consider the possibility of non-epileptic status
– Start emergency antiepileptic drug (AED) therapy
– Perform emergency investigations
– Administer glucose (50 ml of 50% solution) and/or intravenous thiamine as Pabrinex if there is any suggestion of alcohol abuse or impaired nutrition
– Treat severe acidosis if present3rd stage (0-60 minutes):
– Determine the underlying cause of status epilepticus
– Alert the anaesthetist and intensive care unit (ITU)
– Identify and treat any medical complications
– Consider pressor therapy when appropriate4th stage (30-90 minutes):
– Transfer the patient to the intensive care unit
– Establish intensive care and EEG monitoring
– Initiate intracranial pressure monitoring if necessary
– Start initial long-term, maintenance AED therapyEmergency investigations for status epilepticus include blood tests for gases, glucose, renal and liver function, calcium and magnesium, full blood count (including platelets), blood clotting, and AED drug levels. Serum and urine samples should be saved for future analysis, including toxicology if the cause of the convulsive status epilepticus is uncertain. A chest radiograph may be performed to evaluate the possibility of aspiration. Additional investigations, such as brain imaging or lumbar puncture, depend on the clinical circumstances.
Monitoring during the management of status epilepticus involves regular neurological observations and measurements of pulse, blood pressure, and temperature. ECG, biochemistry, blood gases, clotting, and blood count should also be monitored.
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This question is part of the following fields:
- Neurology
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Question 8
Incorrect
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You are managing a 72-year-old male patient who has been intubated as a result of developing acute severe respiratory distress syndrome (ARDS). What measure is utilized to categorize the severity of ARDS?
Your Answer:
Correct Answer: PaO2/FiO2 ratio
Explanation:The PaO2/FiO2 ratio is a measurement used to determine the severity of Acute Respiratory Distress Syndrome (ARDS). It is calculated by dividing the arterial oxygen partial pressure (PaO2) by the fraction of inspired oxygen (FiO2). However, it is important to note that this calculation should only be done when the patient is receiving a minimum positive end-expiratory pressure (PEEP) of 5 cm water. The resulting ratio is then used to classify the severity of ARDS, with specific thresholds provided below.
Further Reading:
ARDS is a severe form of lung injury that occurs in patients with a predisposing risk factor. It is characterized by the onset of respiratory symptoms within 7 days of a known clinical insult, bilateral opacities on chest X-ray, and respiratory failure that cannot be fully explained by cardiac failure or fluid overload. Hypoxemia is also present, as indicated by a specific threshold of the PaO2/FiO2 ratio measured with a minimum requirement of positive end-expiratory pressure (PEEP) ≥5 cm H2O. The severity of ARDS is classified based on the PaO2/FiO2 ratio, with mild, moderate, and severe categories.
Lung protective ventilation is a set of measures aimed at reducing lung damage that may occur as a result of mechanical ventilation. Mechanical ventilation can cause lung damage through various mechanisms, including high air pressure exerted on lung tissues (barotrauma), over distending the lung (volutrauma), repeated opening and closing of lung units (atelectrauma), and the release of inflammatory mediators that can induce lung injury (biotrauma). These mechanisms collectively contribute to ventilator-induced lung injury (VILI).
The key components of lung protective ventilation include using low tidal volumes (5-8 ml/kg), maintaining inspiratory pressures (plateau pressure) below 30 cm of water, and allowing for permissible hypercapnia. However, there are some contraindications to lung protective ventilation, such as an unacceptable level of hypercapnia, acidosis, and hypoxemia. These factors need to be carefully considered when implementing lung protective ventilation strategies in patients with ARDS.
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This question is part of the following fields:
- Respiratory
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Question 9
Incorrect
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You are requested to evaluate a 7-year-old girl who is feeling sick in the Pediatric Emergency Department. Upon reviewing her urea & electrolytes, you observe that her potassium level is elevated at 6.7 mmol/l. She is experiencing occasional palpitations.
As per the APLS guidelines, which medication should be administered promptly when an arrhythmia is present in a child with notable hyperkalemia?Your Answer:
Correct Answer: Calcium chloride
Explanation:Hyperkalemia is a condition where the level of potassium in the blood is higher than normal, specifically greater than 5.5 mmol/l. It can be categorized as mild, moderate, or severe depending on the potassium level. Mild hyperkalemia is when the potassium level is between 5.5-5.9 mmol/l, moderate hyperkalemia is between 6.0-6.4 mmol/l, and severe hyperkalemia is above 6.5 mmol/l. The most common cause of hyperkalemia is renal failure, which can be acute or chronic. Other causes include acidosis, adrenal insufficiency, cell lysis, and excessive potassium intake.
In the treatment of hyperkalemia, calcium plays a crucial role. It works by counteracting the harmful effects of high potassium levels on the heart by stabilizing the cardiac cell membrane. Calcium acts quickly, with its effects seen within 15 minutes, but its effects are relatively short-lived. It is considered a first-line treatment for arrhythmias and significant ECG abnormalities caused by hyperkalemia. However, it is rare to see arrhythmias occur at potassium levels below 7.5 mmol/l.
It’s important to note that calcium does not lower the serum level of potassium. Therefore, when administering calcium, other therapies that actually help lower potassium levels, such as insulin and salbutamol, should also be used. Insulin and salbutamol are effective in reducing serum potassium levels.
When choosing between calcium chloride and calcium gluconate, calcium chloride is preferred when hyperkalemia is accompanied by hemodynamic compromise. This is because calcium chloride contains three times more elemental calcium than an equal volume of calcium gluconate.
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This question is part of the following fields:
- Nephrology
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Question 10
Incorrect
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A 10-year-old girl comes in with sudden abdominal pain. She has a high temperature and feels very nauseous. During the examination, she experiences tenderness in the right iliac fossa. You suspect she may have acute appendicitis.
What is the most frequent location of the appendix's tip?Your Answer:
Correct Answer: Ascending retrocaecal
Explanation:The appendix is a slender and curved tube that is attached to the back and middle part of the caecum. It has a small triangular tissue called the mesoappendix that holds it in place from the tissue of the terminal ileum.
Although it contains a significant amount of lymphoid tissue, the appendix does not serve any important function in humans. The position of the free end of the appendix can vary greatly. There are five main locations where it can be found, with the most common being the retrocaecal and subcaecal positions.
The distribution of these positions is as follows:
– Ascending retrocaecal (64%)
– Subcaecal (32%)
– Transverse retrocaecal (2%)
– Ascending preileal (1%)
– Ascending retroileal (0.5%) -
This question is part of the following fields:
- Surgical Emergencies
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Question 11
Incorrect
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A 45-year-old man comes in with colicky pain in the upper right quadrant, along with nausea and vomiting. You suspect he is having an episode of biliary colic.
Where is the most common place for gallstones to get stuck and cause cholestasis?Your Answer:
Correct Answer: Hartmann’s pouch
Explanation:Biliary colic occurs when a gallstone temporarily blocks either the cystic duct or Hartmann’s pouch, causing the gallbladder to contract. The blockage is relieved when the stone either falls back into the gallbladder or passes through the duct.
Located at the junction of the gallbladder’s neck and the cystic duct, there is a protrusion in the gallbladder wall known as Hartmann’s pouch. This is the most common site for gallstones to become stuck and cause cholestasis.
Patients experiencing biliary colic typically present with intermittent, cramp-like pain in the upper right quadrant of the abdomen. The pain can last anywhere from 15 minutes to 24 hours and is often accompanied by feelings of nausea and vomiting. It is not uncommon for the pain to radiate to the right scapula area.
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This question is part of the following fields:
- Surgical Emergencies
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Question 12
Incorrect
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A 25-year-old patient visits your clinic with concerns about a recent alteration in her usual vaginal discharge. She is not sexually active at the moment and has no other health issues. She does not report any itching symptoms but has observed a strong fishy odor in the discharge.
Which organisms should be the primary target for initial treatment in this scenario?Your Answer:
Correct Answer: Gardnerella vaginalis only
Explanation:Bacterial vaginosis (BV) is a common condition that affects up to a third of women during their childbearing years. It occurs when there is an overgrowth of bacteria, specifically Gardnerella vaginalis. This bacterium is anaerobic, meaning it thrives in environments without oxygen. As it multiplies, it disrupts the balance of bacteria in the vagina, leading to a rise in pH levels and a decrease in lactic acid-producing lactobacilli. It’s important to note that BV is not a sexually transmitted infection.
The main symptom of BV is a greyish discharge with a distinct fishy odor. However, it’s worth mentioning that around 50% of affected women may not experience any symptoms at all.
To diagnose BV, healthcare providers often use Amsel’s criteria. This involves looking for the presence of three out of four specific criteria: a vaginal pH greater than 4.5, a positive fishy smell test when potassium hydroxide is added, the presence of clue cells on microscopy, and a thin, white, homogeneous discharge.
The primary treatment for BV is oral metronidazole, typically taken for 5-7 days. This medication has an initial cure rate of about 75%. It’s crucial to provide special care to pregnant patients diagnosed with BV, as it has been linked to an increased risk of late miscarriage, early labor, and chorioamnionitis. Therefore, prompt treatment for these patients is of utmost importance.
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This question is part of the following fields:
- Sexual Health
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Question 13
Incorrect
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A 60 year old female presents to the emergency department complaining of increasing shortness of breath. The patient reports feeling more fatigued and breathless with minimal exertion over the past few months, but in the past few days, she has been experiencing breathlessness even at rest. She informs you that she has been taking aspirin, ramipril, bisoprolol, and rosuvastatin for the past 5 years since she had a minor heart attack. Upon examination, you observe prominent neck veins, bilateral lung crepitations that are worse at the bases, faint heart sounds, and pitting edema below the knee. The patient's vital signs are as follows:
Blood pressure: 130/84 mmHg
Pulse rate: 90 bpm
Respiration rate: 23 bpm
Temperature: 37.0ÂşC
Oxygen saturation: 93% on room air
What would be the most appropriate initial treatment for this patient?Your Answer:
Correct Answer: Furosemide 40 mg IV
Explanation:Given the patient’s symptoms and physical findings, the most appropriate initial treatment would be to administer Furosemide 40 mg intravenously. Furosemide is a loop diuretic that helps remove excess fluid from the body, which can alleviate symptoms of fluid overload such as shortness of breath and edema. By reducing fluid volume, Furosemide can help improve the patient’s breathing and relieve the strain on the heart.
Further Reading:
Cardiac failure, also known as heart failure, is a clinical syndrome characterized by symptoms and signs resulting from abnormalities in the structure or function of the heart. This can lead to reduced cardiac output or high filling pressures at rest or with stress. Heart failure can be caused by various problems such as myocardial, valvular, pericardial, endocardial, or arrhythmic issues.
The most common causes of heart failure in the UK are coronary heart disease and hypertension. However, there are many other possible causes, including valvular heart disease, structural heart disease, cardiomyopathies, certain drugs or toxins, endocrine disorders, nutritional deficiencies, infiltrative diseases, infections, and arrhythmias. Conditions that increase peripheral demand on the heart, such as anemia, pregnancy, sepsis, hyperthyroidism, Paget’s disease of bone, arteriovenous malformations, and beriberi, can also lead to high-output cardiac failure.
Signs and symptoms of heart failure include edema, lung crepitations, tachycardia, tachypnea, hypotension, displaced apex beat, right ventricular heave, elevated jugular venous pressure, cyanosis, hepatomegaly, ascites, pleural effusions, breathlessness, fatigue, orthopnea, paroxysmal nocturnal dyspnea, nocturnal cough or wheeze, and Presyncope.
To diagnose heart failure, NICE recommends three key tests: N-terminal pro-B-type natriuretic peptide (NT‑proBNP), transthoracic echocardiography, and ECG. Additional tests may include chest X-ray, blood tests (U&Es, thyroid function, LFT’s, lipid profile, HbA1C, FBC), urinalysis, and peak flow or spirometry.
Management of cardiogenic pulmonary edema, a complication of heart failure, involves ensuring a patent airway, optimizing breathing with supplemental oxygen and non-invasive ventilation if necessary, and addressing circulation with loop diuretics to reduce preload, vasodilators to reduce preload and afterload, and inotropes if hypotension or signs of end organ hypoperfusion persist.
In summary, cardiac failure is a clinical syndrome resulting from abnormalities in cardiac function. It can have various causes and is characterized by specific signs and symptoms. Diagnosis involves specific tests, and management focuses on addressing
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This question is part of the following fields:
- Cardiology
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Question 14
Incorrect
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You review a 65-year-old man who has presented with visual problems. He has been taking amiodarone for several years.
Which SINGLE statement regarding the effects of amiodarone on the eye is true?Your Answer:
Correct Answer: Corneal microdeposits are almost universally present in patients taking amiodarone for longer than six months
Explanation:Corneal microdeposits are found in almost all individuals (over 90%) who have been taking amiodarone for more than six months, particularly at doses higher than 400 mg/day. These deposits generally do not cause any symptoms, although approximately 10% of patients may experience a perception of a ‘bluish halo’ around objects they see.
Amiodarone can also have other effects on the eye, but these are much less common, occurring in only 1-2% of patients. These effects include optic neuropathy, nonarteritic anterior ischemic optic neuropathy (N-AION), optic disc swelling, and visual field defects.
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This question is part of the following fields:
- Pharmacology & Poisoning
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Question 15
Incorrect
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A young patient who has been in a car accident experiences a traumatic cardiac arrest. You decide to perform an anterolateral thoracotomy.
During this procedure, which structures will need to be divided?Your Answer:
Correct Answer: Latissimus dorsi
Explanation:An anterolateral thoracotomy is a surgical procedure performed on the front part of the chest wall. It is commonly used in Emergency Department thoracotomy, with a preference for a left-sided approach in patients experiencing traumatic arrest or left-sided chest injuries. However, in cases where patients have not arrested but present with severe low blood pressure and right-sided chest injuries, a right-sided approach is recommended.
The procedure is conducted as follows: an incision is made along the 4th or 5th intercostal space, starting from the sternum at the front and extending to the posterior axillary line. The incision should be deep enough to partially cut through the latissimus dorsi muscle. Subsequently, the skin, subcutaneous fat, and superficial portions of the pectoralis and serratus muscles are divided. The parietal pleura is then divided, allowing access to the pleural cavity. The intercostal muscles are completely cut, and a rib spreader is inserted and opened to provide visualization of the thoracic cavity.
The anterolateral approach enables access to crucial anatomical structures during resuscitation, including the pulmonary hilum, heart, and aorta. In cases where a right-sided heart injury is suspected, an additional incision can be made on the right side, extending across the entire chest. This procedure is known as a bilateral anterolateral thoracotomy or a clamshell thoracotomy.
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This question is part of the following fields:
- Trauma
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Question 16
Incorrect
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A 40-year-old patient with asthma comes to the Emergency Department for an unrelated medical issue. While reviewing their medications, you find out that they are taking theophylline as part of their asthma treatment.
Which ONE of the following medications should be avoided?Your Answer:
Correct Answer: Ciprofloxacin
Explanation:Ciprofloxacin is known to inhibit the activity of cytochrome P450 enzymes, which can lead to increased levels of theophylline in the blood. Therefore, it is recommended to avoid prescribing ciprofloxacin and theophylline together. For more information on the interactions between these two medications, you can refer to the relevant section on theophylline interactions in the British National Formulary (BNF).
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This question is part of the following fields:
- Pharmacology & Poisoning
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Question 17
Incorrect
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You are part of the team working on a child with severe burns. The child has a suspected inhalation injury and needs to be intubated before being transferred to the local burns unit. During direct laryngoscopy, which classification system is used to evaluate the glottic opening?
Your Answer:
Correct Answer: Cormack and Lehane classification
Explanation:The tracheal opening can be classified using the Cormack-Lehane grading system. This system categorizes the views obtained through direct laryngoscopy based on the structures that are visible. More information about this classification system can be found in the notes provided below.
Further Reading:
A difficult airway refers to a situation where factors have been identified that make airway management more challenging. These factors can include body habitus, head and neck anatomy, mouth characteristics, jaw abnormalities, and neck mobility. The LEMON criteria can be used to predict difficult intubation by assessing these factors. The criteria include looking externally at these factors, evaluating the 3-3-2 rule which assesses the space in the mouth and neck, assessing the Mallampati score which measures the distance between the tongue base and roof of the mouth, and considering any upper airway obstructions or reduced neck mobility.
Direct laryngoscopy is a method used to visualize the larynx and assess the size of the tracheal opening. The Cormack-Lehane grading system can be used to classify the tracheal opening, with higher grades indicating more difficult access. In cases of a failed airway, where intubation attempts are unsuccessful and oxygenation cannot be maintained, the immediate priority is to oxygenate the patient and prevent hypoxic brain injury. This can be done through various measures such as using a bag-valve-mask ventilation, high flow oxygen, suctioning, and optimizing head positioning.
If oxygenation cannot be maintained, it is important to call for help from senior medical professionals and obtain a difficult airway trolley if not already available. If basic airway management techniques do not improve oxygenation, further intubation attempts may be considered using different equipment or techniques. If oxygen saturations remain below 90%, a surgical airway such as a cricothyroidotomy may be necessary.
Post-intubation hypoxia can occur for various reasons, and the mnemonic DOPES can be used to identify and address potential problems. DOPES stands for displacement of the endotracheal tube, obstruction, pneumothorax, equipment failure, and stacked breaths. If intubation attempts fail, a maximum of three attempts should be made before moving to an alternative plan, such as using a laryngeal mask airway or considering a cricothyroidotomy.
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This question is part of the following fields:
- Basic Anaesthetics
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Question 18
Incorrect
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A 35-year-old woman has experienced a fracture of the left humerus. During examination, it is found that she has weakness in extending her wrist and metacarpophalangeal joints, leading to wrist drop and an inability to grip with her left hand. However, she still has preserved extension of the elbow. Additionally, there is a loss of sensation over the dorsal aspect of the forearm from below the elbow to the 1st dorsal interosseous.
Which nerve has been damaged in this particular case?Your Answer:
Correct Answer: Radial nerve
Explanation:Radial nerve injuries often occur in conjunction with fractures of the humerus. The most common cause of a radial nerve palsy is external compression or trauma to the radial nerve as it passes through the spiral groove in the middle of the humerus.
There are several factors that can lead to damage of the radial nerve in the spiral groove. These include trauma, such as a fracture in the middle of the humerus, compression known as Saturday night palsy, and iatrogenic causes like injections.
When the radial nerve is injured within the spiral groove, it results in weakness of the wrist and metacarpophalangeal joints. However, elbow extension is not affected because the branches to the triceps and anconeus muscles originate before the spiral groove. The interphalangeal joints remain unaffected as well, as they are supplied by the median and ulnar nerves. Sensory loss will be experienced over the dorsal aspect of the forearm, extending from below the elbow to the 1st dorsal interosseous.
In contrast, injury to the radial nerve in the axilla will also cause weakness of elbow extension and sensory loss in the distribution of the more proximal cutaneous branches. This helps distinguish it from injury in the spiral groove.
In the forearm, the posterior interosseous branch of the radial nerve can also be damaged. This can occur due to injury to the radial head or entrapment in the supinator muscle under the arcade of Frohse. However, this type of injury can be easily distinguished from injury in the spiral groove because there is no sensory involvement and no wrist drop, thanks to the preservation of the extensor carpi radialis longus. Nonetheless, there will still be weakness in the wrist and fingers.
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This question is part of the following fields:
- Neurology
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Question 19
Incorrect
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A 35 year old male is brought into the emergency department after being found disoriented and lethargic by a family member. The family member informs you that the patient has a history of depression and that there were multiple empty bottles of aspirin at the patient's residence. Initial tests are conducted, including a salicylate level.
What is the plasma salicylate concentration threshold for initiating urinary alkalinization in adult patients?Your Answer:
Correct Answer: > 500 mg/L
Explanation:In adults, urinary alkalinisation is initiated when the salicylate level exceeds 500 mg/L (>3.6 mmol/L). For children, the threshold is set at a salicylate concentration of > 350 mg/L (2.5 mmol/L).
Further Reading:
Salicylate poisoning, particularly from aspirin overdose, is a common cause of poisoning in the UK. One important concept to understand is that salicylate overdose leads to a combination of respiratory alkalosis and metabolic acidosis. Initially, the overdose stimulates the respiratory center, leading to hyperventilation and respiratory alkalosis. However, as the effects of salicylate on lactic acid production, breakdown into acidic metabolites, and acute renal injury occur, it can result in high anion gap metabolic acidosis.
The clinical features of salicylate poisoning include hyperventilation, tinnitus, lethargy, sweating, pyrexia (fever), nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.
When investigating salicylate poisoning, it is important to measure salicylate levels in the blood. The sample should be taken at least 2 hours after ingestion for symptomatic patients or 4 hours for asymptomatic patients. The measurement should be repeated every 2-3 hours until the levels start to decrease. Other investigations include arterial blood gas analysis, electrolyte levels (U&Es), complete blood count (FBC), coagulation studies (raised INR/PTR), urinary pH, and blood glucose levels.
To manage salicylate poisoning, an ABC approach should be followed to ensure a patent airway and adequate ventilation. Activated charcoal can be administered if the patient presents within 1 hour of ingestion. Oral or intravenous fluids should be given to optimize intravascular volume. Hypokalemia and hypoglycemia should be corrected. Urinary alkalinization with intravenous sodium bicarbonate can enhance the elimination of aspirin in the urine. In severe cases, hemodialysis may be necessary.
Urinary alkalinization involves targeting a urinary pH of 7.5-8.5 and checking it hourly. It is important to monitor for hypokalemia as alkalinization can cause potassium to shift from plasma into cells. Potassium levels should be checked every 1-2 hours.
In cases where the salicylate concentration is high (above 500 mg/L in adults or 350 mg/L in children), sodium bicarbonate can be administered intravenously. Hemodialysis is the treatment of choice for severe poisoning and may be indicated in cases of high salicylate levels, resistant metabolic acidosis, acute kidney injury, pulmonary edema, seizures and coma.
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This question is part of the following fields:
- Pharmacology & Poisoning
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Question 20
Incorrect
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A 45-year-old woman presents with painless haematuria and undergoes a flexible cystoscopy. A diagnosis of bladder cancer is made following the investigation.
Which of the following is the most significant risk factor for developing bladder cancer in the United Kingdom?Your Answer:
Correct Answer: Smoking
Explanation:Bladder cancer ranks as the seventh most prevalent form of cancer in the United Kingdom, with men outnumbering women by a ratio of 3 to 1. The primary factors that increase the risk of bladder cancer are advancing age and smoking. It is estimated that around 50% of bladder cancer cases are caused by smoking, which is believed to be influenced by the presence of aromatic amines and polycyclic aromatic hydrocarbons that are eliminated through the kidneys. Smokers face a 2 to 6 times higher risk of developing bladder cancer compared to non-smokers.
Additional risk factors for bladder cancer include occupational exposure to aromatic amines found in dyes, paints, solvents, leather dust, combustion products, rubber, and textiles. Radiation therapy to the pelvic region is also considered a risk factor.
In developing nations, particularly in the Middle East, schistosomiasis is responsible for approximately 80% of bladder cancer cases.
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This question is part of the following fields:
- Urology
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Question 21
Incorrect
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A 65-year-old male patient is brought into the emergency department with suspected sepsis. It is decided to intubate the patient pending transfer to the intensive care unit (ICU). Your consultant requests you to prepare propofol and suxamethonium for rapid sequence intubation. What is the mechanism of action of suxamethonium?
Your Answer:
Correct Answer: Non-competitive agonist of acetylcholine receptors at the neuromuscular junction
Explanation:Suxamethonium, also called succinylcholine, is a type of drug used to block neuromuscular transmission. It acts as an agonist by binding to acetylcholine receptors at the neuromuscular junction. Unlike acetylcholine, suxamethonium is not broken down by acetylcholinesterase, which means it stays bound to the receptors for a longer time, leading to prolonged inhibition of neuromuscular transmission. Eventually, suxamethonium is metabolized by plasma cholinesterase.
Further Reading:
Rapid sequence induction (RSI) is a method used to place an endotracheal tube (ETT) in the trachea while minimizing the risk of aspiration. It involves inducing loss of consciousness while applying cricoid pressure, followed by intubation without face mask ventilation. The steps of RSI can be remembered using the 7 P’s: preparation, pre-oxygenation, pre-treatment, paralysis and induction, protection and positioning, placement with proof, and post-intubation management.
Preparation involves preparing the patient, equipment, team, and anticipating any difficulties that may arise during the procedure. Pre-oxygenation is important to ensure the patient has an adequate oxygen reserve and prolongs the time before desaturation. This is typically done by breathing 100% oxygen for 3 minutes. Pre-treatment involves administering drugs to counter expected side effects of the procedure and anesthesia agents used.
Paralysis and induction involve administering a rapid-acting induction agent followed by a neuromuscular blocking agent. Commonly used induction agents include propofol, ketamine, thiopentone, and etomidate. The neuromuscular blocking agents can be depolarizing (such as suxamethonium) or non-depolarizing (such as rocuronium). Depolarizing agents bind to acetylcholine receptors and generate an action potential, while non-depolarizing agents act as competitive antagonists.
Protection and positioning involve applying cricoid pressure to prevent regurgitation of gastric contents and positioning the patient’s neck appropriately. Tube placement is confirmed by visualizing the tube passing between the vocal cords, auscultation of the chest and stomach, end-tidal CO2 measurement, and visualizing misting of the tube. Post-intubation management includes standard care such as monitoring ECG, SpO2, NIBP, capnography, and maintaining sedation and neuromuscular blockade.
Overall, RSI is a technique used to quickly and safely secure the airway in patients who may be at risk of aspiration. It involves a series of steps to ensure proper preparation, oxygenation, drug administration, and tube placement. Monitoring and post-intubation care are also important aspects of RSI.
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This question is part of the following fields:
- Basic Anaesthetics
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Question 22
Incorrect
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A 2-year-old child is diagnosed with a condition that you identify as a reportable infection. You fill out the notification form and reach out to the local health protection team.
What is the most probable diagnosis?Your Answer:
Correct Answer: Mumps
Explanation:Public Health England (PHE) has the primary goal of promptly identifying potential disease outbreaks and epidemics. While accuracy of diagnosis is not the main focus, clinical suspicion of a notifiable infection has been sufficient since 1968.
Registered medical practitioners (RMPs) are legally obligated to inform the designated proper officer at their local council or local health protection team (HPT) about suspected cases of specific infectious diseases.
The Health Protection (Notification) Regulations 2010 outline the diseases that RMPs must report to the proper officers at local authorities. These diseases include acute encephalitis, acute infectious hepatitis, acute meningitis, acute poliomyelitis, anthrax, botulism, brucellosis, cholera, COVID-19, diphtheria, enteric fever (typhoid or paratyphoid fever), food poisoning, haemolytic uraemic syndrome (HUS), infectious bloody diarrhoea, invasive group A streptococcal disease, Legionnaires’ disease, leprosy, malaria, measles, meningococcal septicaemia, mumps, plague, rabies, rubella, severe acute respiratory syndrome (SARS), scarlet fever, smallpox, tetanus, tuberculosis, typhus, viral haemorrhagic fever (VHF), whooping cough, and yellow fever.
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This question is part of the following fields:
- Infectious Diseases
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Question 23
Incorrect
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A 25 year old college student is brought into the ER after being discovered in a collapsed state with decreased consciousness in the early morning hours. You have concerns about the patient's airway and opt to insert an oropharyngeal airway. How would you determine the appropriate size for an oropharyngeal airway?
Your Answer:
Correct Answer: Distance between the patient's incisors and the angle of their mandible
Explanation:The size of an oropharyngeal airway (OPA or Guedel) can be determined by measuring the distance between the patient’s incisors and the angle of their mandible. To ensure proper fit, the OPA should be approximately the same length as this measurement. Please refer to the image in the notes for visual guidance.
Further Reading:
Techniques to keep the airway open:
1. Suction: Used to remove obstructing material such as blood, vomit, secretions, and food debris from the oral cavity.
2. Chin lift manoeuvres: Involves lifting the head off the floor and lifting the chin to extend the head in relation to the neck. Improves alignment of the pharyngeal, laryngeal, and oral axes.
3. Jaw thrust: Used in trauma patients with cervical spine injury concerns. Fingers are placed under the mandible and gently pushed upward.
Airway adjuncts:
1. Oropharyngeal airway (OPA): Prevents the tongue from occluding the airway. Sized according to the patient by measuring from the incisor teeth to the angle of the mandible. Inserted with the tip facing backwards and rotated 180 degrees once it touches the back of the palate or oropharynx.
2. Nasopharyngeal airway (NPA): Useful when it is difficult to open the mouth or in semi-conscious patients. Sized by length (distance between nostril and tragus of the ear) and diameter (roughly that of the patient’s little finger). Contraindicated in basal skull and midface fractures.
Laryngeal mask airway (LMA):
– Supraglottic airway device used as a first line or rescue airway.
– Easy to insert, sized according to patient’s bodyweight.
– Advantages: Easy insertion, effective ventilation, some protection from aspiration.
– Disadvantages: Risk of hypoventilation, greater gastric inflation than endotracheal tube (ETT), risk of aspiration and laryngospasm.Note: Proper training and assessment of the patient’s condition are essential for airway management.
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This question is part of the following fields:
- Basic Anaesthetics
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Question 24
Incorrect
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You evaluate a 30-year-old woman with a confirmed diagnosis of HIV. She inquires about her diagnosis and has some questions for you.
Choose from the options provided below the ONE CD4 count that indicates advanced HIV disease (also referred to as AIDS).Your Answer:
Correct Answer: 200 cells/mm3
Explanation:A normal CD4 count ranges from 500-1000 cells/mm3. In individuals diagnosed with HIV, the CD4 count is typically monitored every 3-6 months. It is important to note that the CD4 count can fluctuate on a daily basis and can be influenced by the timing of the blood test as well as the presence of other infections or illnesses.
When the CD4 count falls below 350 cells/mm3, it is recommended to consider starting antiretroviral therapy. A CD4 count below 200 cells/mm3 is indicative of advanced HIV disease, also known as AIDS defining.
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This question is part of the following fields:
- Infectious Diseases
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Question 25
Incorrect
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A 35 year old male with a history of IV drug use presents to the emergency department complaining of feeling generally unwell, lethargy, and having a fever for the past 2 days. The initial observations are as follows:
- Temperature: 38.6ÂşC
- Pulse rate: 124 bpm
- Blood pressure: 126/80 mmHg
- Respiration rate: 22 bpm
- Oxygen saturation: 98% on room air
During chest auscultation, an audible murmur is detected, leading to a suspicion of infective endocarditis. What is the most likely organism causing this infection?Your Answer:
Correct Answer: Staphylococcus aureus
Explanation:Staphylococcus aureus is the primary organism responsible for infective endocarditis in individuals who use intravenous drugs (IVDUs). In fact, it is not only the most common cause of infective endocarditis overall, but also specifically in IVDUs. Please refer to the additional notes for more detailed information.
Further Reading:
Infective endocarditis (IE) is an infection that affects the innermost layer of the heart, known as the endocardium. It is most commonly caused by bacteria, although it can also be caused by fungi or viruses. IE can be classified as acute, subacute, or chronic depending on the duration of illness. Risk factors for IE include IV drug use, valvular heart disease, prosthetic valves, structural congenital heart disease, previous episodes of IE, hypertrophic cardiomyopathy, immune suppression, chronic inflammatory conditions, and poor dental hygiene.
The epidemiology of IE has changed in recent years, with Staphylococcus aureus now being the most common causative organism in most industrialized countries. Other common organisms include coagulase-negative staphylococci, streptococci, and enterococci. The distribution of causative organisms varies depending on whether the patient has a native valve, prosthetic valve, or is an IV drug user.
Clinical features of IE include fever, heart murmurs (most commonly aortic regurgitation), non-specific constitutional symptoms, petechiae, splinter hemorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots, arthritis, splenomegaly, meningism/meningitis, stroke symptoms, and pleuritic pain.
The diagnosis of IE is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Major criteria include positive blood cultures with typical microorganisms and positive echocardiogram findings. Minor criteria include fever, vascular phenomena, immunological phenomena, and microbiological phenomena. Blood culture and echocardiography are key tests for diagnosing IE.
In summary, infective endocarditis is an infection of the innermost layer of the heart that is most commonly caused by bacteria. It can be classified as acute, subacute, or chronic and can be caused by a variety of risk factors. Staphylococcus aureus is now the most common causative organism in most industrialized countries. Clinical features include fever, heart murmurs, and various other symptoms. The diagnosis is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Blood culture and echocardiography are important tests for diagnosing IE.
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This question is part of the following fields:
- Infectious Diseases
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Question 26
Incorrect
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Large numbers of casualties are observed after a suspected CBRN (chemical, biological, radiological, and nuclear) incident. It is believed that sarin gas is the responsible agent. Which combination of clinical features is most likely to be present?
Your Answer:
Correct Answer: Miosis, bronchorrhoea, salivation and muscle weakness
Explanation:The nerve agents, also known as nerve gases, are a group of highly toxic chemical warfare agents that were initially developed just before and during World War II.
The first compounds to be created are called the G agents (G stands for German, as they were discovered and synthesized by German scientists). These include Tabun (GA), Sarin (GB), and Soman (GD).
In the 1950s, the V agents (V stands for venomous) were synthesized and are approximately 10 times more poisonous than sarin. These include Venomous agent X (VX), Venomous agent E (VE), Venomous agent G (VG), and Venomous agent M (VM).
One of the most well-known incidents involving the use of a nerve agent was the March 1995 Tokyo subway sarin attack. During this attack, Sarin was released into the Tokyo subway system during rush hour. As a result, over 5,000 people sought medical attention. Among them, 984 were moderately poisoned, 54 were severely poisoned, and 12 died.
Nerve agents are organophosphorus esters that are chemically related to organophosphorus insecticides. They work by inhibiting acetylcholinesterase (AChE), an enzyme that breaks down the neurotransmitter acetylcholine (ACh). This leads to an accumulation of ACh at both muscarinic and nicotinic cholinergic receptors.
Nerve agents can be absorbed through any body surface. When dispersed as a spray or aerosol, they can be absorbed through the skin, eyes, and respiratory tract. When dispersed as a vapor, they are primarily absorbed through the respiratory tract and eyes. If a sufficient amount of agent is absorbed, local effects are followed by generalized systemic effects.
The clinical features observed after exposure are a result of a combination of muscarinic, nicotinic, and central nervous system effects.
Muscarinic effects (DUMBBELS):
– Diarrhea
– Urination
– Miosis
– Bronchorrhea
– Bronchospasm
– Emesis
– Lacrimation
– Salivation
Plus bradycardia and hypotension.Nicotinic effects:
– Sweating
– Tremor
– Fasciculations
– Muscle weakness
– Flaccid paralysisCentral nervous system effects:
– Agitation and irritability
– Amnesia
– Ataxia
– Respiratory -
This question is part of the following fields:
- Major Incident Management & PHEM
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Question 27
Incorrect
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A 4-year-old child is brought in by ambulance. He has been experiencing seizures for the past 35 minutes. He has received two doses of IV lorazepam. His bowel movement is normal, and he is not taking any medication.
According to the current APLS guidelines, what would be the most suitable next course of action in managing his condition?Your Answer:
Correct Answer: Set up phenytoin infusion
Explanation:The current algorithm for the treatment of a convulsing child, known as APLS, is as follows:
Step 1 (5 minutes after the start of convulsion):
If a child has been convulsing for 5 minutes or more, the initial dose of benzodiazepine should be administered. This can be done by giving Lorazepam at a dose of 0.1 mg/kg intravenously (IV) or intraosseously (IO) if vascular access is available. Alternatively, buccal midazolam at a dose of 0.5 mg/kg or rectal diazepam at a dose of 0.5 mg/kg can be given if vascular access is not available.Step 2 (10 minutes after the start of Step 1):
If the convulsion continues for a further 10 minutes, a second dose of benzodiazepine should be given. It is also important to summon senior help at this point.Step 3 (10 minutes after the start of Step 2):
At this stage, it is necessary to involve senior help to reassess the child and provide guidance on further management. The recommended approach is as follows:
– If the child is not already on phenytoin, a phenytoin infusion should be initiated. This involves administering 20 mg/kg of phenytoin intravenously over a period of 20 minutes.
– If the child is already taking phenytoin, phenobarbitone can be used as an alternative. The recommended dose is 20 mg/kg administered intravenously over 20 minutes.
– In the meantime, rectal paraldehyde can be considered at a dose of 0.8 ml/kg of the 50:50 mixture while preparing the infusion.Step 4 (20 minutes after the start of Step 3):
If the child is still experiencing convulsions at this stage, it is crucial to have an anaesthetist present. A rapid sequence induction with thiopental is recommended for further management.Please note that this algorithm is subject to change based on individual patient circumstances and the guidance of medical professionals.
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This question is part of the following fields:
- Neurology
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Question 28
Incorrect
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A 32 year old male arrives at the emergency department about 1 hour after completing a SCUBA dive. The patient reports experiencing a headache, dizziness, and discomfort in the shoulders and knees. You inform the patient that you suspect he is suffering from 'the bends' and proceed to explain how gas bubbles expand in size as divers ascend and water pressure decreases. Which scientific principle describes the correlation between gas volume and absolute pressure?
Your Answer:
Correct Answer: Boyle's law
Explanation:Boyle’s law states that when the temperature remains constant, the volume of a gas is inversely related to its pressure. This means that as the pressure of a gas increases, its volume decreases, and vice versa. Mathematically, this relationship can be expressed as P1V1 = P2V2.
Further Reading:
Decompression illness (DCI) is a term that encompasses both decompression sickness (DCS) and arterial gas embolism (AGE). When diving underwater, the increasing pressure causes gases to become more soluble and reduces the size of gas bubbles. As a diver ascends, nitrogen can come out of solution and form gas bubbles, leading to decompression sickness or the bends. Boyle’s and Henry’s gas laws help explain the changes in gases during changing pressure.
Henry’s law states that the amount of gas that dissolves in a liquid is proportional to the partial pressure of the gas. Divers often use atmospheres (ATM) as a measure of pressure, with 1 ATM being the pressure at sea level. Boyle’s law states that the volume of gas is inversely proportional to the pressure. As pressure increases, volume decreases.
Decompression sickness occurs when nitrogen comes out of solution as a diver ascends. The evolved gas can physically damage tissue by stretching or tearing it as bubbles expand, or by provoking an inflammatory response. Joints and spinal nervous tissue are commonly affected. Symptoms of primary damage usually appear immediately or soon after a dive, while secondary damage may present hours or days later.
Arterial gas embolism occurs when nitrogen bubbles escape into the arterial circulation and cause distal ischemia. The consequences depend on where the embolism lodges, ranging from tissue ischemia to stroke if it lodges in the cerebral arterial circulation. Mechanisms for distal embolism include pulmonary barotrauma, right to left shunt, and pulmonary filter overload.
Clinical features of decompression illness vary, but symptoms often appear within six hours of a dive. These can include joint pain, neurological symptoms, chest pain or breathing difficulties, rash, vestibular problems, and constitutional symptoms. Factors that increase the risk of DCI include diving at greater depth, longer duration, multiple dives close together, problems with ascent, closed rebreather circuits, flying shortly after diving, exercise shortly after diving, dehydration, and alcohol use.
Diagnosis of DCI is clinical, and investigations depend on the presentation. All patients should receive high flow oxygen, and a low threshold for ordering a chest X-ray should be maintained. Hydration is important, and IV fluids may be necessary. Definitive treatment is recompression therapy in a hyperbaric oxygen chamber, which should be arranged as soon as possible. Entonox should not be given, as it will increase the pressure effect in air spaces.
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This question is part of the following fields:
- Environmental Emergencies
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Question 29
Incorrect
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You review a patient with chronic severe back pain with a medical student that has examined the patient. He feels the most likely diagnosis is lumbar disc herniation. He explains that all five features of Reynold’s pentad are present.
Which of the following does NOT form part of Reynold’s pentad?Your Answer:
Correct Answer: Raised white cell count
Explanation:Ascending cholangitis occurs when there is an infection in the common bile duct, usually caused by a stone that has led to a blockage of bile flow. This condition is known as choledocholithiasis. The typical symptoms of ascending cholangitis are jaundice, fever (often accompanied by chills), and pain in the upper right quadrant of the abdomen. It is important to note that ascending cholangitis is a serious medical emergency that can be life-threatening, as patients often develop sepsis. Approximately 10-20% of patients may also experience altered mental status and low blood pressure due to septic shock. When these additional symptoms are present along with the classic triad of symptoms (Charcot’s triad), it is referred to as Reynold’s pentad. Urgent biliary drainage is the recommended treatment for ascending cholangitis. While a high white blood cell count is commonly seen in this condition, it is not considered part of Reynold’s pentad.
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This question is part of the following fields:
- Surgical Emergencies
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Question 30
Incorrect
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A 9-month-old girl comes in with a significant haemarthrosis in her left knee after falling while trying to stand up using a side table. Her mother mentions that her older sister has a bleeding disorder and has also had haemarthrosis before.
What is the MOST probable diagnosis?Your Answer:
Correct Answer: Haemophilia A
Explanation:Haemophilia is a collection of genetic disorders that are inherited and lead to impaired blood clotting. Haemophilia A specifically occurs when there is a deficiency of factor VIII and is typically passed down as a recessive trait on the X chromosome.
The initial signs of haemophilia A usually appear around 6 months of age when infants start crawling, although it can manifest later. Bleeding can occur either spontaneously or as a result of trauma. One key indicator of haemophilia is bleeding into muscles and joints, known as haemarthrosis. While gastrointestinal and cerebral bleeding can also happen, they are less common occurrences.
Based on the symptoms described, the most likely diagnosis from the given options would be Haemophilia A, especially when there is a combination of haemarthrosis and an older brother with the same disorder.
Idiopathic thrombocytopenic purpura (ITP) is a condition where the immune system causes a decrease in platelet count. Antibodies target the glycoprotein IIb-IIIa or Ib complex. Acute ITP is more prevalent in children and affects both sexes equally. Chronic ITP, on the other hand, is more common in young to middle-aged women. Unlike haemophilia, ITP typically presents with symptoms such as nosebleeds, oral bleeding, purpura, or petechiae, rather than haemarthrosis. Additionally, ITP is not an inherited disorder.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited disorder that follows an X-linked recessive pattern. It is characterized by a defect in the G6PD enzyme, which plays a crucial role in red blood cell metabolism. Most individuals with G6PD deficiency do not experience symptoms. However, haemolytic crisis can occur in response to factors like illness (especially infection and diabetic ketoacidosis), certain medications (such as specific antibiotics, antimalarials, sulphonamides, and aspirin), or certain foods (notably fava beans).
Von Willebrand disease (vWD) is the most common hereditary coagulation disorder, affecting approximately 1 in 100 individuals. It arises from a deficiency in Von Willebrand factor (vWF), which leads to reduced levels of factor VIII. vWF is responsible for protecting factor VIII from rapid breakdown in the blood and is also necessary for platelet adhesion.
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This question is part of the following fields:
- Haematology
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