Ulnar nerve lesions can be assessed using Froment’s sign. To perform this test, a piece of paper is placed between the patient’s thumb and index finger. The examiner then tries to pull the paper out of the patient’s pinched grip. If the patient has an ulnar nerve palsy, they will struggle to maintain the grip and may compensate by flexing the flexor pollicis longus muscle of the thumb to maintain pressure. This compensation is evident when the patient’s interphalangeal joint of the thumb flexes. Froment’s sign is a useful indicator of ulnar nerve dysfunction.

Tinea cruris, commonly known as ‘jock itch’, is a fungal infection that affects the groin area. It is primarily caused by Trichophyton rubrum and is more prevalent in young men, particularly athletes. The typical symptoms include a reddish or brownish rash that is accompanied by intense itching. Pustules and vesicles may also develop, and there is often a raised border with a clear center. Notably, the infection usually does not affect the penis and scrotum.

It is worth mentioning that patients with tinea cruris often have concurrent tinea pedis, also known as athlete’s foot, which may have served as the source of the infection. The infection can be transmitted through sharing towels or by using towels that have come into contact with infected feet, leading to the spread of the fungus to the groin area.

Fortunately, treatment for tinea cruris typically involves the use of topical imidazole creams, such as clotrimazole. This is usually sufficient to alleviate the symptoms and eradicate the infection. Alternatively, terbinafine cream can be used as an alternative treatment option.

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.

This question revolves around the challenge of delivering difficult news. The family involved in this situation have good intentions as they aim to shield their loved one from the distress of understanding the true nature of their underlying condition.

However, if the patient possesses the mental capacity to comprehend, it is important to disclose the details of their condition if they express a desire to know. Engage in an open and sensitive conversation with the patient, allowing them to determine the extent of information they wish to receive about their condition.

For further information, refer to the GMC Guidance on the topic of utilizing and divulging patient information for direct care.
https://www.gmc-uk.org/ethical-guidance/ethical-guidance-for-doctors/confidentiality/using-and-disclosing-patient-information-for-direct-care

Anticholinergic drugs work by blocking the effects of acetylcholine, a neurotransmitter, in both the central and peripheral nervous systems. These drugs are commonly used in clinical practice and include antihistamines, typical and atypical antipsychotics, anticonvulsants, antidepressants, antispasmodics, antiemetics, antiparkinsonian agents, antimuscarinics, and certain plants. When someone ingests an anticholinergic drug, they may experience a toxidrome, which is characterized by an agitated delirium and various signs of acetylcholine receptor blockade in the central and peripheral systems.

The central effects of anticholinergic drugs result in an agitated delirium, which is marked by fluctuating mental status, confusion, restlessness, visual hallucinations, picking at objects in the air, mumbling, slurred speech, disruptive behavior, tremor, myoclonus, and in rare cases, coma or seizures. On the other hand, the peripheral effects can vary and may include dilated pupils, sinus tachycardia, dry mouth, hot and flushed skin, increased body temperature, urinary retention, and ileus.

The typical range for the partial pressure of carbon dioxide (pCO2) is 4.4-6.4 kilopascals (kPa). In terms of arterial blood gas (ABG) results, the normal range for pO2 (partial pressure of oxygen) is 10-14.4 kPa or 70-100 millimeters of mercury (mmHg). The normal range for pCO2 is 4.4-6.4 kPa or 35-45 mmHg. Additionally, the normal range for bicarbonate levels is 23-28 millimoles per liter (mmol/L).

Further Reading:

Arterial blood gases (ABG) are an important diagnostic tool used to assess a patient’s acid-base status and respiratory function. When obtaining an ABG sample, it is crucial to prioritize safety measures to minimize the risk of infection and harm to the patient. This includes performing hand hygiene before and after the procedure, wearing gloves and protective equipment, disinfecting the puncture site with alcohol, using safety needles when available, and properly disposing of equipment in sharps bins and contaminated waste bins.

To reduce the risk of harm to the patient, it is important to test for collateral circulation using the modified Allen test for radial artery puncture. Additionally, it is essential to inquire about any occlusive vascular conditions or anticoagulation therapy that may affect the procedure. The puncture site should be checked for signs of infection, injury, or previous surgery. After the test, pressure should be applied to the puncture site or the patient should be advised to apply pressure for at least 5 minutes to prevent bleeding.

Interpreting ABG results requires a systematic approach. The core set of results obtained from a blood gas analyser includes the partial pressures of oxygen and carbon dioxide, pH, bicarbonate concentration, and base excess. These values are used to assess the patient’s acid-base status.

The pH value indicates whether the patient is in acidosis, alkalosis, or within the normal range. A pH less than 7.35 indicates acidosis, while a pH greater than 7.45 indicates alkalosis.

The respiratory system is assessed by looking at the partial pressure of carbon dioxide (pCO2). An elevated pCO2 contributes to acidosis, while a low pCO2 contributes to alkalosis.

The metabolic aspect is assessed by looking at the bicarbonate (HCO3-) level and the base excess. A high bicarbonate concentration and base excess indicate alkalosis, while a low bicarbonate concentration and base excess indicate acidosis.

Analyzing the pCO2 and base excess values can help determine the primary disturbance and whether compensation is occurring. For example, a respiratory acidosis (elevated pCO2) may be accompanied by metabolic alkalosis (elevated base excess) as a compensatory response.

The anion gap is another important parameter that can help determine the cause of acidosis. It is calculated by subtracting the sum of chloride and bicarbonate from the sum of sodium and potassium.

Benign paroxysmal positional vertigo (BPPV) occurs when there is dysfunction in the inner ear. This dysfunction causes the otoliths, which are located in the utricle, to become dislodged from their normal position and migrate into one of the semicircular canals over time. As a result, these detached otoliths continue to move even after head movement has stopped, leading to vertigo due to the conflicting sensation of ongoing movement with other sensory inputs.

While the majority of BPPV cases have no identifiable cause (idiopathic), approximately 40% of cases can be attributed to factors such as head injury, spontaneous labyrinthine degeneration, post-viral illness, middle ear surgery, or chronic middle ear disease.

The main clinical features of BPPV include symptoms that are provoked by head movement, rolling over, and upward gaze. These episodes are typically brief, lasting less than 5 minutes, and are often worse in the mornings. Unlike other inner ear disorders, BPPV does not cause hearing loss or tinnitus. Nausea is a common symptom, while vomiting is rare. The Dix-Hallpike test can be used to confirm the diagnosis of BPPV.

It is important to note that vestibular suppressant medications have not been proven to be beneficial in managing BPPV. These medications do not improve symptoms or reduce the duration of the disease.

The treatment of choice for BPPV is the Epley manoeuvre. This maneuver aims to reposition the dislodged otoliths back into the utricles from the semicircular canals. A 2014 Cochrane review concluded that the Epley manoeuvre is a safe and effective treatment for BPPV, with a number needed to treat of 2-4.

Referral to an ENT specialist is recommended for patients with BPPV in the following situations: if the treating clinician is unable to perform or access the Epley manoeuvre, if the Epley manoeuvre has not been beneficial after repeated attempts (minimum two), if the patient has been symptomatic for more than 4 weeks, or if the patient has experienced more than 3 episodes of BPPV.

Congenital adrenal hyperplasia (CAH) is a group of inherited disorders that are caused by autosomal recessive genes. The majority of affected patients, over 90%, have a deficiency of the enzyme 21-hydroxylase. This enzyme is encoded by the 21-hydroxylase gene, which is located on chromosome 6p21 within the HLA histocompatibility complex. The second most common cause of CAH is a deficiency of the enzyme 11-beta-hydroxylase. The condition is rare, with an incidence of approximately 1 in 500 births in the UK. It is more prevalent in the offspring of consanguineous marriages.

The deficiency of 21-hydroxylase leads to a deficiency of cortisol and/or aldosterone, as well as an excess of precursor steroids. As a result, there is an increased secretion of ACTH from the anterior pituitary, leading to adrenocortical hyperplasia.

The severity of CAH varies depending on the degree of 21-hydroxylase deficiency. Female infants often exhibit ambiguous genitalia, such as clitoral hypertrophy and labial fusion. Male infants may have an enlarged scrotum and/or scrotal pigmentation. Hirsutism, or excessive hair growth, occurs in 10% of cases.

Boys with CAH often experience a salt-losing adrenal crisis at around 1-3 weeks of age. This crisis is characterized by symptoms such as vomiting, weight loss, floppiness, and circulatory collapse.

The diagnosis of CAH can be made by detecting markedly elevated levels of the metabolic precursor 17-hydroxyprogesterone. Neonatal screening is possible, primarily through the identification of persistently elevated 17-hydroxyprogesterone levels.

In infants presenting with a salt-losing crisis, the following biochemical abnormalities are observed: hyponatremia (low sodium levels), hyperkalemia (high potassium levels), metabolic acidosis, and hypoglycemia.

Boys experiencing a salt-losing crisis will require fluid resuscitation, intravenous dextrose, and intravenous hydrocortisone.

Affected females will require corrective surgery for their external genitalia. However, they have an intact uterus and ovaries and are capable of having children.

The long-term management of both sexes involves lifelong replacement of hydrocortisone (to suppress ACTH levels).

Vomiting is a common occurrence during the early stages of pregnancy, typically happening between 7 and 12 weeks. However, there is a more severe condition called hyperemesis gravidarum, which involves uncontrollable and intense nausea and vomiting. This condition can lead to imbalances in fluids and electrolytes, significant ketonuria, malnutrition, and weight loss. It is relatively rare, affecting less than 1% of pregnancies.

For mild cases of nausea and vomiting in early pregnancy, dietary adjustments and non-pharmacological measures like consuming ginger or using P6 wrist acupressure can often provide relief.

In severe cases where heavy ketonuria and severe dehydration are present, hospital admission is usually necessary for intravenous fluid rehydration. The NICE Clinical Knowledge Summary (CKS) on nausea and vomiting in pregnancy recommends using oral promethazine, oral cyclizine, or oral prochlorperazine as the first-line treatment if an antiemetic is needed. After 24 hours, the situation should be reassessed to determine if the initial treatment is effective. If not, a second-line drug like metoclopramide or ondansetron should be considered.

It’s important to note that metoclopramide should not be used in patients under the age of 20 due to the increased risk of extrapyramidal side effects. Additionally, proton pump inhibitors (e.g., omeprazole) and histamine H2-receptor antagonists (e.g., ranitidine) can be beneficial for women experiencing significant dyspepsia alongside their nausea and vomiting.

For more information, you can refer to the NICE CKS on nausea and vomiting in pregnancy.

Lipid emulsion is known to cause pancreatitis as a common side effect. According to the AAGBI guidelines, patients who are given lipid emulsion should be closely monitored with regular clinical evaluations. This includes conducting amylase or lipase tests daily for two days after receiving the emulsion.

Further Reading:

Local anaesthetics, such as lidocaine, bupivacaine, and prilocaine, are commonly used in the emergency department for topical or local infiltration to establish a field block. Lidocaine is often the first choice for field block prior to central line insertion. These anaesthetics work by blocking sodium channels, preventing the propagation of action potentials.

However, local anaesthetics can enter the systemic circulation and cause toxic side effects if administered in high doses. Clinicians must be aware of the signs and symptoms of local anaesthetic systemic toxicity (LAST) and know how to respond. Early signs of LAST include numbness around the mouth or tongue, metallic taste, dizziness, visual and auditory disturbances, disorientation, and drowsiness. If not addressed, LAST can progress to more severe symptoms such as seizures, coma, respiratory depression, and cardiovascular dysfunction.

The management of LAST is largely supportive. Immediate steps include stopping the administration of local anaesthetic, calling for help, providing 100% oxygen and securing the airway, establishing IV access, and controlling seizures with benzodiazepines or other medications. Cardiovascular status should be continuously assessed, and conventional therapies may be used to treat hypotension or arrhythmias. Intravenous lipid emulsion (intralipid) may also be considered as a treatment option.

If the patient goes into cardiac arrest, CPR should be initiated following ALS arrest algorithms, but lidocaine should not be used as an anti-arrhythmic therapy. Prolonged resuscitation may be necessary, and intravenous lipid emulsion should be administered. After the acute episode, the patient should be transferred to a clinical area with appropriate equipment and staff for further monitoring and care.

It is important to report cases of local anaesthetic toxicity to the appropriate authorities, such as the National Patient Safety Agency in the UK or the Irish Medicines Board in the Republic of Ireland. Additionally, regular clinical review should be conducted to exclude pancreatitis, as intravenous lipid emulsion can interfere with amylase or lipase assays.

The presence of certain clinical features can indicate the possibility of acute severe asthma in children over the age of 5. These features include oxygen saturations below 92%, peak flow measurements below 50% of what is expected, a heart rate exceeding 120 beats per minute, a respiratory rate exceeding 30 breaths per minute, and the use of accessory muscles.

Transfusion transmitted bacterial infection is a rare complication that can occur during blood transfusion. It is more commonly associated with platelet transfusion, as platelets are stored at room temperature. Additionally, previously frozen components that are thawed using a water bath and red cell components stored for several weeks are also at a higher risk for bacterial infection.

Both Gram-positive and Gram-negative bacteria have been implicated in transfusion-transmitted bacterial infection, but Gram-negative bacteria are known to cause more severe illness and have higher rates of morbidity and mortality. Among the bacterial organisms, Yersinia enterocolitica is the most commonly associated with this type of infection. This particular organism is able to multiply at low temperatures and utilizes iron as a nutrient, making it well-suited for proliferation in blood stores.

The clinical features of transfusion-transmitted bacterial infection typically manifest shortly after the transfusion begins. These features include a high fever, chills and rigors, nausea and vomiting, tachycardia, hypotension, and even circulatory collapse.

If there is suspicion of a transfusion-transmitted bacterial infection, it is crucial to immediately stop the transfusion. Blood cultures and a Gram-stain should be requested to identify the specific bacteria causing the infection. Broad-spectrum antibiotics should be initiated promptly. Furthermore, the blood pack should be returned to the blood bank urgently for culture and Gram-stain analysis.

The first step in managing hypertension in patients with phaeochromocytoma is to use alpha blockade, usually with a medication called phenoxybenzamine. This is followed by beta blockade. Before undergoing surgery to remove the phaeochromocytoma, patients need to be on both alpha and beta blockers. Alpha blockade is typically achieved by giving phenoxybenzamine intravenously at a dose of 10-40 mg over one hour, and then switching to an oral form (10-60 mg/day in divided doses). It is important to start alpha blockade at least 7 to 10 days before surgery to allow for an increase in blood volume. Beta blockade is only considered once alpha blockade has been achieved, as starting beta blockers too soon can lead to a dangerous increase in blood pressure.

Further Reading:

Phaeochromocytoma is a rare neuroendocrine tumor that secretes catecholamines. It typically arises from chromaffin tissue in the adrenal medulla, but can also occur in extra-adrenal chromaffin tissue. The majority of cases are spontaneous and occur in individuals aged 40-50 years. However, up to 30% of cases are hereditary and associated with genetic mutations. About 10% of phaeochromocytomas are metastatic, with extra-adrenal tumors more likely to be metastatic.

The clinical features of phaeochromocytoma are a result of excessive catecholamine production. Symptoms are typically paroxysmal and include hypertension, headaches, palpitations, sweating, anxiety, tremor, abdominal and flank pain, and nausea. Catecholamines have various metabolic effects, including glycogenolysis, mobilization of free fatty acids, increased serum lactate, increased metabolic rate, increased myocardial force and rate of contraction, and decreased systemic vascular resistance.

Diagnosis of phaeochromocytoma involves measuring plasma and urine levels of metanephrines, catecholamines, and urine vanillylmandelic acid. Imaging studies such as abdominal CT or MRI are used to determine the location of the tumor. If these fail to find the site, a scan with metaiodobenzylguanidine (MIBG) labeled with radioactive iodine is performed. The highest sensitivity and specificity for diagnosis is achieved with plasma metanephrine assay.

The definitive treatment for phaeochromocytoma is surgery. However, before surgery, the patient must be stabilized with medical management. This typically involves alpha-blockade with medications such as phenoxybenzamine or phentolamine, followed by beta-blockade with medications like propranolol. Alpha blockade is started before beta blockade to allow for expansion of blood volume and to prevent a hypertensive crisis.

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 referred to as the G agents (with G representing 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 (with V standing for venomous) were synthesized, and they 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 lost their lives.

The 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 30-point Folstein mini-mental state examination (MMSE) includes a task where the examiner asks the individual to repeat back a phrase. However, this task is not included in the AMTS. The AMTS consists of ten questions that assess different aspects of cognitive function. These questions cover topics such as age, time, year, location, recognition of people, date of birth, historical events, present monarch or prime minister, counting backwards, and recall of an address. The AMTS is a useful tool for evaluating memory loss and is referenced in the RCEM syllabus.

When it comes to managing bacterial conjunctivitis, NICE provides some helpful guidance. It is important to inform the patient that most cases of bacterial conjunctivitis will resolve on their own within 5-7 days without any treatment. However, in severe cases or situations where a quick resolution is necessary, topical antibiotics may be necessary. In some cases, it may be appropriate to delay treatment and advise the patient to start using topical antibiotics if their symptoms have not improved within 3 days.

There are a few options for topical antibiotics that can be used. One option is Chloramphenicol 0.5% drops, which should be applied every 2 hours for 2 days and then 4 times daily for 5 days. Another option is Chloramphenicol 1% ointment, which should be applied four times daily for 2 days and then twice daily for 5 days. Fusidic acid 1% eye drops can also be used as a second-line treatment and should be applied twice daily for 7 days.

By following these guidelines, healthcare professionals can effectively manage bacterial conjunctivitis and provide appropriate treatment options for their patients.

Central retinal vein occlusion (CRVO) typically results in painless, one-sided vision loss. On fundoscopic examination, the retina displays a distinct appearance resembling a ‘pizza thrown against a wall’. This includes engorged retinal veins, swelling of the optic disc, multiple flame-shaped hemorrhages, and cotton wool spots. Hypertension is present in about 65% of CRVO patients, and it is more common in individuals over 65 years old.

In contrast, central retinal artery occlusion (CRAO) also causes sudden, painless, one-sided vision loss. However, the retina’s appearance in CRAO is different from CRVO. It appears pale, with narrowed blood vessels. A notable feature is the presence of a ‘cherry-red spot’ at the center of the macula, which is supplied by the underlying choroid. Examination often reveals an afferent pupillary defect.

Vitreous hemorrhage occurs when there is bleeding into the middle chamber of the eye, known as the vitreous. This can be caused by conditions such as proliferative diabetic retinopathy, trauma, or retinal detachment. The appearance of vitreous hemorrhage is described as ‘blood within a bloodless gel’, resulting in a diffuse red appearance of the retina. Unlike CRVO, there are no focal flame-shaped hemorrhages.

Diabetic maculopathy refers to the presence of diabetic eye disease within a one-disc diameter of the macula.

Wet age-related macular degeneration (ARMD) causes vision loss due to choroidal neovascularization, which leads to leakage of blood and protein beneath the macula. While there may be hemorrhages visible on the retina, the overall appearance does not match the description provided in the question.

The second heart sound (S2) is created by vibrations produced when the aortic and pulmonary valves close. It marks the end of systole. It is normal to hear a split in the sound during inspiration.

A loud S2 can be associated with certain conditions such as systemic hypertension (resulting in a loud A2), pulmonary hypertension (resulting in a loud P2), hyperdynamic states (like tachycardia, fever, or thyrotoxicosis), and atrial septal defect (which causes a loud P2).

On the other hand, a soft S2 can be linked to decreased aortic diastolic pressure (as seen in aortic regurgitation), poorly mobile cusps (such as calcification of the aortic valve), aortic root dilatation, and pulmonary stenosis (which causes a soft P2).

A widely split S2 can occur during deep inspiration, right bundle branch block, prolonged right ventricular systole (seen in conditions like pulmonary stenosis or pulmonary embolism), and severe mitral regurgitation. However, in the case of atrial septal defect, the splitting is fixed and does not vary with respiration.

Reversed splitting of S2, where P2 occurs before A2 (paradoxical splitting), can occur during deep expiration, left bundle branch block, prolonged left ventricular systole (as seen in hypertrophic cardiomyopathy), severe aortic stenosis, and right ventricular pacing.

Compartment syndrome can occur when there are circumferential burns on the arms or legs. This typically happens with full thickness burns, where the burnt skin becomes stiff and compresses the compartment, making it difficult for blood to flow out. To treat this condition, escharotomy and possibly fasciotomy may be necessary.

Further Reading:

Burn injuries can be classified based on their type (degree, partial thickness or full thickness), extent as a percentage of total body surface area (TBSA), and severity (minor, moderate, major/severe). Severe burns are defined as a >10% TBSA in a child and >15% TBSA in an adult.

When assessing a burn, it is important to consider airway injury, carbon monoxide poisoning, type of burn, extent of burn, special considerations, and fluid status. Special considerations may include head and neck burns, circumferential burns, thorax burns, electrical burns, hand burns, and burns to the genitalia.

Airway management is a priority in burn injuries. Inhalation of hot particles can cause damage to the respiratory epithelium and lead to airway compromise. Signs of inhalation injury include visible burns or erythema to the face, soot around the nostrils and mouth, burnt/singed nasal hairs, hoarse voice, wheeze or stridor, swollen tissues in the mouth or nostrils, and tachypnea and tachycardia. Supplemental oxygen should be provided, and endotracheal intubation may be necessary if there is airway obstruction or impending obstruction.

The initial management of a patient with burn injuries involves conserving body heat, covering burns with clean or sterile coverings, establishing IV access, providing pain relief, initiating fluid resuscitation, measuring urinary output with a catheter, maintaining nil by mouth status, closely monitoring vital signs and urine output, monitoring the airway, preparing for surgery if necessary, and administering medications.

Burns can be classified based on the depth of injury, ranging from simple erythema to full thickness burns that penetrate into subcutaneous tissue. The extent of a burn can be estimated using methods such as the rule of nines or the Lund and Browder chart, which takes into account age-specific body proportions.

Fluid management is crucial in burn injuries due to significant fluid losses. Evaporative fluid loss from burnt skin and increased permeability of blood vessels can lead to reduced intravascular volume and tissue perfusion. Fluid resuscitation should be aggressive in severe burns, while burns <15% in adults and <10% in children may not require immediate fluid resuscitation. The Parkland formula can be used to calculate the intravenous fluid requirements for someone with a significant burn injury.

This individual is diagnosed with an acquired cholesteatoma, which is an expanding growth of the stratified keratinising epithelium in the middle ear. It develops due to dysfunction of the Eustachian tube and chronic otitis media caused by the retraction of the squamous elements of the tympanic membrane into the middle ear space.

The most important method for assessing the presence of a cholesteatoma is otoscopy. A retraction pocket observed in the attic or posterosuperior quadrant of the tympanic membrane is a characteristic sign of an acquired cholesteatoma. This is often accompanied by the presence of granulation tissue and squamous debris. The presence of a granular polyp within the ear canal also strongly suggests a cholesteatoma.

If left untreated, a cholesteatoma can lead to various complications including conductive deafness, facial nerve palsy, brain abscess, meningitis, and labyrinthitis. Therefore, it is crucial to urgently refer this individual to an ear, nose, and throat (ENT) specialist for a CT scan and surgical removal of the lesion.

The optic chiasm is situated just below the hypothalamus and is in close proximity to the pituitary gland. When the pituitary gland enlarges, it can impact the functioning of the optic nerve at this location. Specifically, the fibres from the nasal half of the retina cross over at the optic chiasm to form the optic tracts. Compression at the optic chiasm primarily affects these fibres, resulting in a visual defect that affects peripheral vision in both eyes, known as bitemporal hemianopia. There are several causes of optic chiasm lesions, with the most common being a pituitary tumor. Other causes include craniopharyngioma, meningioma, optic glioma, and internal carotid artery aneurysm. The diagram below provides a summary of the different visual field defects that can occur at various points in the visual pathway.

Calcium-channel blocker overdose is a serious condition that can be life-threatening. The most dangerous types of calcium channel blockers in overdose are verapamil and diltiazem. These medications work by binding to the alpha-1 subunit of L-type calcium channels, which prevents the entry of calcium into cells. These channels are important for the functioning of cardiac myocytes, vascular smooth muscle cells, and islet beta-cells.

When managing a patient with calcium-channel blocker overdose, it is crucial to follow the standard ABC approach for resuscitation. If there is a risk of life-threatening toxicity, early intubation and ventilation should be considered. Invasive blood pressure monitoring is also necessary if hypotension and shock are developing.

The specific treatments for calcium-channel blocker overdose primarily focus on supporting the cardiovascular system. These treatments include:

1. Fluid resuscitation: Administer up to 20 mL/kg of crystalloid solution.

2. Calcium administration: This can temporarily increase blood pressure and heart rate. Options include 10% calcium gluconate (60 mL IV) or 10% calcium chloride (20 mL IV) via central venous access. Repeat boluses can be given up to three times, and a calcium infusion may be necessary to maintain serum calcium levels above 2.0 mEq/L.

3. Atropine: Consider administering 0.6 mg every 2 minutes, up to a total of 1.8 mg. However, atropine is often ineffective in these cases.

4. High dose insulin – euglycemic therapy (HIET): The use of HIET in managing cardiovascular toxicity has evolved. It used to be a last-resort measure, but early administration is now increasingly recommended. This involves giving a bolus of short-acting insulin (1 U/kg) and 50 mL of 50% glucose IV (unless there is marked hyperglycemia). Therapy should be continued with a short-acting insulin/dextrose infusion. Glucose levels should be monitored frequently, and potassium should be replaced if levels drop below 2.5 mmol/L.

5. Vasoactive infusions: Catecholamines such as dopamine, adrenaline, and/or noradrenaline can be titrated to achieve the desired inotropic and chronotropic effects.

6. Sodium bicarbonate: Consider using sodium bicarbonate in cases where a severe metabolic acidosis develops.

In the UK, not all dementia cases are suitable for treatment with acetylcholinesterase inhibitors and memantine. Specifically, patients with frontotemporal dementia should not be prescribed these medications. If a patient experiences visual hallucinations, it may indicate that they have dementia with Lewy bodies.

Further Reading:

Dementia is a progressive and irreversible clinical syndrome characterized by cognitive and behavioral symptoms. These symptoms include memory loss, impaired reasoning and communication, personality changes, and reduced ability to carry out daily activities. The decline in cognition affects multiple domains of intellectual functioning and is not solely due to normal aging.

To diagnose dementia, a person must have impairment in at least two cognitive domains that significantly impact their daily activities. This impairment cannot be explained by delirium or other major psychiatric disorders. Early-onset dementia refers to dementia that develops before the age of 65.

The most common cause of dementia is Alzheimer’s disease, accounting for 50-75% of cases. Other causes include vascular dementia, dementia with Lewy bodies, and frontotemporal dementia. Less common causes include Parkinson’s disease dementia, Huntington’s disease, prion disease, and metabolic and endocrine disorders.

There are several risk factors for dementia, including age, mild cognitive impairment, genetic predisposition, excess alcohol intake, head injury, depression, learning difficulties, diabetes, obesity, hypertension, smoking, Parkinson’s disease, low social engagement, low physical activity, low educational attainment, hearing impairment, and air pollution.

Assessment of dementia involves taking a history from the patient and ideally a family member or close friend. The person’s current level of cognition and functional capabilities should be compared to their baseline level. Physical examination, blood tests, and cognitive assessment tools can also aid in the diagnosis.

Differential diagnosis for dementia includes normal age-related memory changes, mild cognitive impairment, depression, delirium, vitamin deficiencies, hypothyroidism, adverse drug effects, normal pressure hydrocephalus, and sensory deficits.

Management of dementia involves a multi-disciplinary approach that includes non-pharmacological and pharmacological measures. Non-pharmacological interventions may include driving assessment, modifiable risk factor management, and non-pharmacological therapies to promote cognition and independence. Drug treatments for dementia should be initiated by specialists and may include acetylcholinesterase inhibitors, memantine, and antipsychotics in certain cases.

In summary, dementia is a progressive and irreversible syndrome characterized by cognitive and behavioral symptoms. It has various causes and risk factors, and its management involves a multi-disciplinary approach.

The drugs that have the highest association with the development of drug-induced lupus are procainamide and hydralazine. While some of the other medications mentioned in this question have also been reported to cause drug-induced lupus, the strength of their association is much weaker.

Maintaining adequate blood pressure is crucial in managing increased intracranial pressure (ICP). The recommended blood pressure targets may vary depending on the source. The Scottish Intercollegiate Guidelines Network (SIGN) suggests maintaining an adequate blood pressure, while the 4th edition of the Brain Trauma Foundation recommends maintaining a systolic blood pressure (SBP) above 100 mm Hg for individuals aged 50-69 years (or above 110 mm Hg for those aged 15-49 years) to reduce mortality and improve outcomes.

When managing a patient with increased ICP, the initial steps should include maintaining normal body temperature to prevent fever, positioning the patient with a 30º head-up tilt, and administering analgesia and sedation as needed. It is important to monitor and maintain blood pressure, using inotropes if necessary to achieve the target. Additionally, preparations should be made to use medications such as Mannitol or hypertonic saline to lower ICP if required. Hyperventilation may also be considered, although it carries the risk of inducing ischemia and requires monitoring of carbon dioxide levels.

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

In the UK, the most commonly used treatment for acute exacerbations of hereditary angioedema (HAE) in emergency departments is C1-Esterase inhibitor. However, there are alternative options available. Icatibant acetate, sold under the brand name Firazyr®, is a bradykinin receptor antagonist that is licensed in the UK and Europe and can be used as an alternative treatment. Another alternative is the transfusion of fresh frozen plasma.

Further Reading:

Angioedema and urticaria are related conditions that involve swelling in different layers of tissue. Angioedema refers to swelling in the deeper layers of tissue, such as the lips and eyelids, while urticaria, also known as hives, refers to swelling in the epidermal skin layers, resulting in raised red areas of skin with itching. These conditions often coexist and may have a common underlying cause.

Angioedema can be classified into allergic and non-allergic types. Allergic angioedema is the most common type and is usually triggered by an allergic reaction, such as to certain medications like penicillins and NSAIDs. Non-allergic angioedema has multiple subtypes and can be caused by factors such as certain medications, including ACE inhibitors, or underlying conditions like hereditary angioedema (HAE) or acquired angioedema.

HAE is an autosomal dominant disease characterized by a deficiency of C1 esterase inhibitor. It typically presents in childhood and can be inherited or acquired as a result of certain disorders like lymphoma or systemic lupus erythematosus. Acquired angioedema may have similar clinical features to HAE but is caused by acquired deficiencies of C1 esterase inhibitor due to autoimmune or lymphoproliferative disorders.

The management of urticaria and allergic angioedema focuses on ensuring the airway remains open and addressing any identifiable triggers. In mild cases without airway compromise, patients may be advised that symptoms will resolve without treatment. Non-sedating antihistamines can be used for up to 6 weeks to relieve symptoms. Severe cases of urticaria may require systemic corticosteroids in addition to antihistamines. In moderate to severe attacks of allergic angioedema, intramuscular epinephrine may be considered.

The management of HAE involves treating the underlying deficiency of C1 esterase inhibitor. This can be done through the administration of C1 esterase inhibitor, bradykinin receptor antagonists, or fresh frozen plasma transfusion, which contains C1 inhibitor.

In summary, angioedema and urticaria are related conditions involving swelling in different layers of tissue. They can coexist and may have a common underlying cause. Management involves addressing triggers, using antihistamines, and in severe cases, systemic corticosteroids or other specific treatments for HAE.

Pityriasis versicolor, also known as tinea versicolor, is a common skin condition caused by an infection with the yeasts Malassezia furfur and Malassezia globosa. It typically presents as multiple patches of altered pigmentation, primarily on the trunk. In individuals with fair skin, these patches are usually darker in color, while in those with darker skin or a tan, they may appear lighter (known as pityriasis versicolor alba). It is not uncommon for the rash to cause itching.

The recommended treatment for pityriasis versicolor involves the use of antifungal agents. One particularly effective option is ketoconazole shampoo, which is sold under the brand name Nizoral. To use this shampoo, it should be applied to the affected areas and left on for approximately five minutes before being rinsed off. This process should be repeated daily for a total of five days.

The BTS guidelines categorize acute asthma into four classifications: moderate, acute severe, life-threatening, and near-fatal.

Moderate asthma is characterized by increasing symptoms and a peak expiratory flow rate (PEFR) between 50-75% of the best or predicted value. There are no signs of acute severe asthma present in this classification.

Acute severe asthma is identified by any one of the following criteria: a PEFR between 33-50% of the best or predicted value, a respiratory rate exceeding 25 breaths per minute, a heart rate over 110 beats per minute, or the inability to complete sentences in one breath.

Life-threatening asthma is determined by any one of the following indicators: a PEFR below 33% of the best or predicted value, a blood oxygen saturation level (SpO2) below 92%, a partial pressure of oxygen (PaO2) below 8 kilopascals (kPa), a normal partial pressure of carbon dioxide (PaCO2) between 4.6-6.0 kPa, a silent chest, cyanosis, poor respiratory effort, arrhythmia, exhaustion, altered conscious level, or hypotension.

Near-fatal asthma is characterized by elevated PaCO2 levels and/or the need for mechanical ventilation with increased inflation pressures.

Cricoid pressure is applied during intubation to compress the oesophagus and prevent the backflow of stomach contents, reducing the risk of aspiration.

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.

Calcium-channel blocker overdose is a serious matter and should always be treated as potentially life-threatening. The two most dangerous types of calcium channel blockers in overdose are verapamil and diltiazem. These medications work by binding to the alpha-1 subunit of L-type calcium channels, which prevents the entry of calcium into cells. These channels play a crucial role in the functioning of cardiac myocytes, vascular smooth muscle cells, and islet beta-cells.

The toxic effects of calcium-channel blockers can be summarized as follows:

Cardiac effects:
– Excessive negative inotropy: causing myocardial depression
– Negative chronotropy: leading to sinus bradycardia
– Negative dromotropy: resulting in atrioventricular node blockade

Vascular smooth muscle tone effects:
– Decreased afterload: causing systemic hypotension
– Coronary vasodilation: leading to widened blood vessels in the heart

Metabolic effects:
– Hypoinsulinaemia: insulin release depends on calcium influx through L-type calcium channels in islet beta-cells
– Calcium channel blocker-induced insulin resistance: causing reduced responsiveness to insulin.

It is important to be aware of these effects and take appropriate action in cases of calcium-channel blocker overdose.