The Parkinson-plus syndromes are a group of neurodegenerative disorders that share similar features with Parkinson’s disease but also have additional clinical characteristics that set them apart from idiopathic Parkinson’s disease (iPD). These syndromes include Multiple System Atrophy (MSA), Progressive Supranuclear Palsy (PSP), Corticobasal degeneration (CBD), and Dementia with Lewy Bodies (DLB).

Multiple System Atrophy (MSA) is a less common condition than iPD and PSP. It is characterized by the loss of cells in multiple areas of the nervous system. MSA progresses rapidly, often leading to wheelchair dependence within 3-4 years of diagnosis. Some distinguishing features of MSA include autonomic dysfunction, bladder control problems, erectile dysfunction, blood pressure changes, early-onset balance problems, neck or facial dystonia, and a high-pitched voice.

To summarize the distinguishing features of the Parkinson-plus syndromes compared to iPD, the following table provides a comparison:

iPD:
– Symptom onset: One side of the body affected more than the other
– Tremor: Typically starts at rest on one side of the body
– Levodopa response: Excellent response
– Mental changes: Depression
– Balance/falls: Late in the disease
– Common eye abnormalities: Dry eyes, trouble focusing

MSA:
– Symptom onset: Both sides equally affected
– Tremor: Not common but may occur
– Levodopa response: Minimal response (but often tried in early stages of disease)
– Mental changes: Depression
– Balance/falls: Within 1-3 years
– Common eye abnormalities: Dry eyes, trouble focusing

PSP:
– Symptom onset: Both sides equally affected
– Tremor: Less common, if present affects both sides
– Levodopa response: Minimal response (but often tried in early stages of disease)
– Mental changes: Personality changes, depression
– Balance/falls: Within 1 year
– Common eye abnormalities: Dry eyes, difficulty in looking downwards

CBD:
– Symptom onset: One side of the body affected more than the other
– Tremor: Not common but may occur
– Levodopa response: Minimal response (but often tried in early stages of disease)
– Mental changes: Depression
– Balance/falls: Within 1-3 years
– Common eye abnormalities: Dry eyes, trouble focusing

ACE inhibitors work by inhibiting the conversion of angiotensin I to angiotensin II. As a result, the effects of angiotensin II are reduced, leading to the dilation of vascular smooth muscle and the efferent arteriole of the glomerulus. This, in turn, has several effects on renal measurements. Firstly, it causes an increase in renal plasma flow. Secondly, it leads to a decrease in filtration fraction. Lastly, it results in a decrease in glomerular filtration rate.

Infectious mononucleosis, also known as glandular fever, is a condition that is not clearly defined in medical literature. It is characterized by symptoms such as a sore throat, swollen tonsils with a whitish coating, enlarged lymph nodes in the neck, fatigue, and an enlarged liver and spleen. This condition is caused by a specific virus.

Further Reading:

Glandular fever, also known as infectious mononucleosis or mono, is a clinical syndrome characterized by symptoms such as sore throat, fever, and swollen lymph nodes. It is primarily caused by the Epstein-Barr virus (EBV), with other viruses and infections accounting for the remaining cases. Glandular fever is transmitted through infected saliva and primarily affects adolescents and young adults. The incubation period is 4-8 weeks.

The majority of EBV infections are asymptomatic, with over 95% of adults worldwide having evidence of prior infection. Clinical features of glandular fever include fever, sore throat, exudative tonsillitis, lymphadenopathy, and prodromal symptoms such as fatigue and headache. Splenomegaly (enlarged spleen) and hepatomegaly (enlarged liver) may also be present, and a non-pruritic macular rash can sometimes occur.

Glandular fever can lead to complications such as splenic rupture, which increases the risk of rupture in the spleen. Approximately 50% of splenic ruptures associated with glandular fever are spontaneous, while the other 50% follow trauma. Diagnosis of glandular fever involves various investigations, including viral serology for EBV, monospot test, and liver function tests. Additional serology tests may be conducted if EBV testing is negative.

Management of glandular fever involves supportive care and symptomatic relief with simple analgesia. Antiviral medication has not been shown to be beneficial. It is important to identify patients at risk of serious complications, such as airway obstruction, splenic rupture, and dehydration, and provide appropriate management. Patients can be advised to return to normal activities as soon as possible, avoiding heavy lifting and contact sports for the first month to reduce the risk of splenic rupture.

Rare but serious complications associated with glandular fever include hepatitis, upper airway obstruction, cardiac complications, renal complications, neurological complications, haematological complications, chronic fatigue, and an increased risk of lymphoproliferative cancers and multiple sclerosis.

Acute kidney injury (AKI), previously known as acute renal failure, is a sudden decline in kidney function. This results in the accumulation of waste products and disturbances in fluid and electrolyte balance. AKI can occur in individuals with previously normal kidney function or those with pre-existing kidney disease, known as acute-on-chronic kidney disease. It is a relatively common condition, with approximately 15% of adults admitted to hospitals in the UK developing AKI.

The causes of AKI can be categorized into pre-renal, intrinsic renal, and post-renal factors. The majority of AKI cases in the community are due to pre-renal causes, accounting for 90% of cases. These are often associated with conditions such as hypotension from sepsis or fluid depletion. Medications, particularly ACE inhibitors and NSAIDs, are also frequently implicated in AKI.

The table below summarizes the most common causes of AKI:

Pre-renal:
– Volume depletion (e.g., hemorrhage, severe vomiting or diarrhea, burns)
– Oedematous states (e.g., cardiac failure, liver cirrhosis, nephrotic syndrome)
– Hypotension (e.g., cardiogenic shock, sepsis, anaphylaxis)
– Cardiovascular conditions (e.g., severe cardiac failure, arrhythmias)
– Renal hypoperfusion: NSAIDs, COX-2 inhibitors, ACE inhibitors or ARBs, Abdominal aortic aneurysm
– Renal artery stenosis
– Hepatorenal syndrome

Intrinsic renal:
– Glomerular disease (e.g., glomerulonephritis, thrombosis, hemolytic-uremic syndrome)
– Tubular injury: acute tubular necrosis (ATN) following prolonged ischemia
– Acute interstitial nephritis due to drugs (e.g., NSAIDs), infection, or autoimmune diseases
– Vascular disease (e.g., vasculitis, polyarteritis nodosa, thrombotic microangiopathy, cholesterol emboli, renal vein thrombosis, malignant hypertension)
– Eclampsia

Post-renal:
– Renal stones
– Blood clot
– Papillary necrosis
– Urethral stricture
– Prostatic hypertrophy or malignancy
– Bladder tumor
– Radiation fibrosis
– Pelvic malignancy
– Retroperitoneal fibrosis

Occlusion of branches of the anterior spinal artery leads to the development of the medial medullary syndrome. This condition is characterized by several distinct symptoms. Firstly, there is contralateral hemiplegia, which occurs due to damage to the pyramidal tracts. Additionally, there is contralateral loss of joint position sense, vibratory sense, and discriminatory touch, resulting from damage to the medial lemniscus. Lastly, there is ipsilateral deviation and paralysis of the tongue, which is caused by damage to the hypoglossal nucleus.

Prolongation of the QT interval can lead to a dangerous ventricular arrhythmia called torsades de pointes, which can result in sudden cardiac death. There are several commonly used medications that are known to cause QT prolongation.

Low levels of potassium (hypokalaemia) and magnesium (hypomagnesaemia) can increase the risk of QT prolongation. For example, diuretics can interact with QT-prolonging drugs by causing hypokalaemia.

The QT interval varies with heart rate, and formulas are used to correct the QT interval for heart rate. Once corrected, it is referred to as the QTc interval. The QTc interval is typically reported on the ECG printout. A normal QTc interval is less than 440 ms.

If the QTc interval is greater than 440 ms but less than 500 ms, it is considered borderline. Although there may be some variation in the literature, a QTc interval within these values is generally considered borderline prolonged. In such cases, it is important to consider reducing the dose of QT-prolonging drugs or switching to an alternative medication that does not prolong the QT interval.

A prolonged QTc interval exceeding 500 ms is clinically significant and is likely to increase the risk of arrhythmia. Any medications that prolong the QT interval should be reviewed immediately.

Here are some commonly encountered drugs that are known to prolong the QT interval:

Antimicrobials:
– Erythromycin
– Clarithromycin
– Moxifloxacin
– Fluconazole
– Ketoconazole

Antiarrhythmics:
– Dronedarone
– Sotalol
– Quinidine
– Amiodarone
– Flecainide

Antipsychotics:
– Risperidone
– Fluphenazine
– Haloperidol
– Pimozide
– Chlorpromazine
– Quetiapine
– Clozapine

Antidepressants:
– Citalopram/escitalopram
– Amitriptyline
– Clomipramine
– Dosulepin
– Doxepin
– Imipramine
– Lofepramine

Antiemetics:
– Domperidone
– Droperidol
– Ondansetron/Granisetron

Others:
– Methadone
– Protein kinase inhibitors (e.g. sunitinib)

To perform rapid sequence induction in adults, it is recommended to administer a dose of sodium thiopentone ranging from 3 to 5 mg per kilogram of body weight.

Further Reading:

There are four commonly used induction agents in the UK: propofol, ketamine, thiopentone, and etomidate.

Propofol is a 1% solution that produces significant venodilation and myocardial depression. It can also reduce cerebral perfusion pressure. The typical dose for propofol is 1.5-2.5 mg/kg. However, it can cause side effects such as hypotension, respiratory depression, and pain at the site of injection.

Ketamine is another induction agent that produces a dissociative state. It does not display a dose-response continuum, meaning that the effects do not necessarily increase with higher doses. Ketamine can cause bronchodilation, which is useful in patients with asthma. The initial dose for ketamine is 0.5-2 mg/kg, with a typical IV dose of 1.5 mg/kg. Side effects of ketamine include tachycardia, hypertension, laryngospasm, unpleasant hallucinations, nausea and vomiting, hypersalivation, increased intracranial and intraocular pressure, nystagmus and diplopia, abnormal movements, and skin reactions.

Thiopentone is an ultra-short acting barbiturate that acts on the GABA receptor complex. It decreases cerebral metabolic oxygen and reduces cerebral blood flow and intracranial pressure. The adult dose for thiopentone is 3-5 mg/kg, while the child dose is 5-8 mg/kg. However, these doses should be halved in patients with hypovolemia. Side effects of thiopentone include venodilation, myocardial depression, and hypotension. It is contraindicated in patients with acute porphyrias and myotonic dystrophy.

Etomidate is the most haemodynamically stable induction agent and is useful in patients with hypovolemia, anaphylaxis, and asthma. It has similar cerebral effects to thiopentone. The dose for etomidate is 0.15-0.3 mg/kg. Side effects of etomidate include injection site pain, movement disorders, adrenal insufficiency, and apnoea. It is contraindicated in patients with sepsis due to adrenal suppression.

The rash in measles typically begins as a maculopapular rash on the face and behind the ears. Within 24-36 hours, it spreads to the trunk and limbs. The rash may merge together, especially on the face, creating a confluent appearance. Usually, the rash appears along with a high fever. Before the rash appears, there are usually symptoms of a cold for 2-3 days. Koplik spots, which are blue-white spots on the inside of the cheeks (usually seen opposite the molars), can be observed 1-2 days before the rash appears and can be detected during a mouth examination.

It is important to note that the rash in rubella infection is similar to that of measles. However, there are two key differences: the presence of Koplik spots and a high fever (>38.3ºC) are characteristic of measles. Erythema infectiosum, on the other hand, causes a rash that resembles a slapped cheek.

Further Reading:

Measles is a highly contagious viral infection caused by an RNA paramyxovirus. It is primarily spread through aerosol transmission, specifically through droplets in the air. The incubation period for measles is typically 10-14 days, during which patients are infectious from 4 days before the appearance of the rash to 4 days after.

Common complications of measles include pneumonia, otitis media (middle ear infection), and encephalopathy (brain inflammation). However, a rare but fatal complication called subacute sclerosing panencephalitis (SSPE) can also occur, typically presenting 5-10 years after the initial illness.

The onset of measles is characterized by a prodrome, which includes symptoms such as irritability, malaise, conjunctivitis, and fever. Before the appearance of the rash, white spots known as Koplik spots can be seen on the buccal mucosa. The rash itself starts behind the ears and then spreads to the entire body, presenting as a discrete maculopapular rash that becomes blotchy and confluent.

In terms of complications, encephalitis typically occurs 1-2 weeks after the onset of the illness. Febrile convulsions, giant cell pneumonia, keratoconjunctivitis, corneal ulceration, diarrhea, increased incidence of appendicitis, and myocarditis are also possible complications of measles.

When managing contacts of individuals with measles, it is important to offer the MMR vaccine to children who have not been immunized against measles. The vaccine-induced measles antibody develops more rapidly than that following natural infection, so it should be administered within 72 hours of contact.

When children with diabetic ketoacidosis (DKA) show signs of shock such as low blood pressure, fast heart rate, and poor peripheral perfusion, it is important for clinicians to consider DKA as a possible cause. In these cases, the initial treatment should involve giving a fluid bolus of 10 ml/kg to help stabilize the patient.

Further Reading:

Diabetic ketoacidosis (DKA) is a serious complication of diabetes that occurs due to a lack of insulin in the body. It is most commonly seen in individuals with type 1 diabetes but can also occur in type 2 diabetes. DKA is characterized by hyperglycemia, acidosis, and ketonaemia.

The pathophysiology of DKA involves insulin deficiency, which leads to increased glucose production and decreased glucose uptake by cells. This results in hyperglycemia and osmotic diuresis, leading to dehydration. Insulin deficiency also leads to increased lipolysis and the production of ketone bodies, which are acidic. The body attempts to buffer the pH change through metabolic and respiratory compensation, resulting in metabolic acidosis.

DKA can be precipitated by factors such as infection, physiological stress, non-compliance with insulin therapy, acute medical conditions, and certain medications. The clinical features of DKA include polydipsia, polyuria, signs of dehydration, ketotic breath smell, tachypnea, confusion, headache, nausea, vomiting, lethargy, and abdominal pain.

The diagnosis of DKA is based on the presence of ketonaemia or ketonuria, blood glucose levels above 11 mmol/L or known diabetes mellitus, and a blood pH below 7.3 or bicarbonate levels below 15 mmol/L. Initial investigations include blood gas analysis, urine dipstick for glucose and ketones, blood glucose measurement, and electrolyte levels.

Management of DKA involves fluid replacement, electrolyte correction, insulin therapy, and treatment of any underlying cause. Fluid replacement is typically done with isotonic saline, and potassium may need to be added depending on the patient’s levels. Insulin therapy is initiated with an intravenous infusion, and the rate is adjusted based on blood glucose levels. Monitoring of blood glucose, ketones, bicarbonate, and electrolytes is essential, and the insulin infusion is discontinued once ketones are below 0.3 mmol/L, pH is above 7.3, and bicarbonate is above 18 mmol/L.

Complications of DKA and its treatment include gastric stasis, thromboembolism, electrolyte disturbances, cerebral edema, hypoglycemia, acute respiratory distress syndrome, and acute kidney injury. Prompt medical intervention is crucial in managing DKA to prevent potentially fatal outcomes.

In cases where there are no contraindications, high-dose NSAIDs are the recommended initial treatment for acute gout. A commonly used and effective regimen is to administer a stat dose of Naproxen 750 mg, followed by 250 mg three times a day. It is important to note that Aspirin should not be used in gout as it hinders the urinary clearance of urate and interferes with the action of uricosuric agents. Instead, more appropriate choices include Naproxen, diclofenac, or indomethacin.

Allopurinol is typically used as a prophylactic measure to prevent future gout attacks by reducing serum uric acid levels. However, it should not be initiated during the acute phase of an attack as it can worsen the severity and duration of symptoms.

Colchicine works by binding to tubulin and preventing neutrophil migration into the joint. It is just as effective as NSAIDs in relieving acute gout attacks. Additionally, it has a role in prophylactic treatment if a patient cannot tolerate Allopurinol.

It is important to note that NSAIDs are contraindicated in patients with heart failure as they can lead to fluid retention and congestive cardiac failure. In such cases, Colchicine is the preferred treatment option for patients with heart failure or those who cannot tolerate NSAIDs.

Parkinson’s disease is often accompanied by two prevalent diseases, namely dementia and depression. Dementia is observed in approximately 20 to 40% of individuals diagnosed with Parkinson’s disease. On the other hand, depression is experienced by around 45% of patients with Parkinson’s disease.

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.

Infectious factors that can lead to back pain consist of discitis, vertebral osteomyelitis, and spinal epidural abscess. There are certain warning signs, known as red flags, that indicate the presence of an infectious cause for back pain. These red flags include experiencing a fever, having tuberculosis, being diabetic, having recently had a bacterial infection such as a urinary tract infection, engaging in intravenous drug use, and having a weakened immune system due to conditions like HIV or the use of immunosuppressant drugs.

Ketamine should not be used in children under 12 months old due to the increased risk of laryngospasm and airway complications. The Royal College of Emergency Medicine advises against using ketamine in children under 1 year old in the emergency department, and it should only be administered by experienced clinicians in children aged 5 and under. Ketamine may cause a slight increase in blood pressure and heart rate, making it a suitable option for those with low blood pressure. However, it is contraindicated in individuals with malignant hypertension (blood pressure above 180 mmHg). Please refer to the notes below for additional contraindications.

Further Reading:

Procedural sedation is commonly used by emergency department (ED) doctors to minimize pain and discomfort during procedures that may be painful or distressing for patients. Effective procedural sedation requires the administration of analgesia, anxiolysis, sedation, and amnesia. This is typically achieved through the use of a combination of short-acting analgesics and sedatives.

There are different levels of sedation, ranging from minimal sedation (anxiolysis) to general anesthesia. It is important for clinicians to understand the level of sedation being used and to be able to manage any unintended deeper levels of sedation that may occur. Deeper levels of sedation are similar to general anesthesia and require the same level of care and monitoring.

Various drugs can be used for procedural sedation, including propofol, midazolam, ketamine, and fentanyl. Each of these drugs has its own mechanism of action and side effects. Propofol is commonly used for sedation, amnesia, and induction and maintenance of general anesthesia. Midazolam is a benzodiazepine that enhances the effect of GABA on the GABA A receptors. Ketamine is an NMDA receptor antagonist and is used for dissociative sedation. Fentanyl is a highly potent opioid used for analgesia and sedation.

The doses of these drugs for procedural sedation in the ED vary depending on the drug and the route of administration. It is important for clinicians to be familiar with the appropriate doses and onset and peak effect times for each drug.

Safe sedation requires certain requirements, including appropriate staffing levels, competencies of the sedating practitioner, location and facilities, and monitoring. The level of sedation being used determines the specific requirements for safe sedation.

After the procedure, patients should be monitored until they meet the criteria for safe discharge. This includes returning to their baseline level of consciousness, having vital signs within normal limits, and not experiencing compromised respiratory status. Pain and discomfort should also be addressed before discharge.

An overdose of Amitriptyline, a tricyclic antidepressant, leads to a toxic effect known as anticholinergic toxidrome. This occurs when the muscarinic acetylcholine receptors are blocked, causing the characteristic signs and symptoms associated with this condition.

Further Reading:

Tricyclic antidepressant (TCA) overdose is a common occurrence in emergency departments, with drugs like amitriptyline and dosulepin being particularly dangerous. TCAs work by inhibiting the reuptake of norepinephrine and serotonin in the central nervous system. In cases of toxicity, TCAs block various receptors, including alpha-adrenergic, histaminic, muscarinic, and serotonin receptors. This can lead to symptoms such as hypotension, altered mental state, signs of anticholinergic toxicity, and serotonin receptor effects.

TCAs primarily cause cardiac toxicity by blocking sodium and potassium channels. This can result in a slowing of the action potential, prolongation of the QRS complex, and bradycardia. However, the blockade of muscarinic receptors also leads to tachycardia in TCA overdose. QT prolongation and Torsades de Pointes can occur due to potassium channel blockade. TCAs can also have a toxic effect on the myocardium, causing decreased cardiac contractility and hypotension.

Early symptoms of TCA overdose are related to their anticholinergic properties and may include dry mouth, pyrexia, dilated pupils, agitation, sinus tachycardia, blurred vision, flushed skin, tremor, and confusion. Severe poisoning can lead to arrhythmias, seizures, metabolic acidosis, and coma. ECG changes commonly seen in TCA overdose include sinus tachycardia, widening of the QRS complex, prolongation of the QT interval, and an R/S ratio >0.7 in lead aVR.

Management of TCA overdose involves ensuring a patent airway, administering activated charcoal if ingestion occurred within 1 hour and the airway is intact, and considering gastric lavage for life-threatening cases within 1 hour of ingestion. Serial ECGs and blood gas analysis are important for monitoring. Intravenous fluids and correction of hypoxia are the first-line therapies. IV sodium bicarbonate is used to treat haemodynamic instability caused by TCA overdose, and benzodiazepines are the treatment of choice for seizure control. Other treatments that may be considered include glucagon, magnesium sulfate, and intravenous lipid emulsion.

There are certain things to avoid in TCA overdose, such as anti-arrhythmics like quinidine and flecainide, as they can prolonged depolarization.

Delirium is an acute syndrome that causes disturbances in consciousness, attention, cognition, and perception. It is also known as an acute confusional state. The DSM-IV criteria for diagnosing delirium include recent onset of fluctuating awareness, impairment of memory and attention, and disorganized thinking. Delirium typically develops over hours to days and may be accompanied by behavioral changes, personality changes, and psychotic features. It often occurs in individuals with predisposing factors, such as advanced age or multiple comorbidities, when exposed to new precipitating factors, such as medications or infection. Symptoms of delirium fluctuate throughout the day, with lucid intervals occurring during the day and worse disturbances at night. Falling and loss of appetite are often warning signs of delirium.

Delirium can be classified into three subtypes based on the person’s symptoms. Hyperactive delirium is characterized by inappropriate behavior, hallucinations, and agitation. Restlessness and wandering are common in this subtype. Hypoactive delirium is characterized by lethargy, reduced concentration, and appetite. The person may appear quiet or withdrawn. Mixed delirium presents with signs and symptoms of both hyperactive and hypoactive subtypes.

The exact pathophysiology of delirium is not fully understood, but it is believed to involve multiple mechanisms, including cholinergic deficiency, dopaminergic excess, and inflammation. The cause of delirium is usually multifactorial, with predisposing factors and precipitating factors playing a role. Predisposing factors include older age, cognitive impairment, frailty, significant injuries, and iatrogenic events. Precipitating factors include infection, metabolic or electrolyte disturbances, cardiovascular disorders, respiratory disorders, neurological disorders, endocrine disorders, urological disorders, gastrointestinal disorders, severe uncontrolled pain, alcohol intoxication or withdrawal, medication use, and psychosocial factors.

Delirium is highly prevalent in hospital settings, affecting up to 50% of patients aged over 65 and occurring in 30% of people aged over 65 presenting to the emergency department. Complications of delirium include increased risk of death, high in-hospital mortality rates, higher mortality rates following hospital discharge, increased length of stay in hospital, nosocomial infections, increased risk of admission to long-term care or re-admission to hospital, increased incidence of dementia, increased risk of falls and associated injuries, pressure sores.

According to the latest guidelines from NICE and the BNF, the recommended initial treatment for typhoid fever is cefotaxime. It is important to note that infections originating from the Middle-East, South Asia, and South-East Asia may have multiple antibiotic resistance, so it is advisable to test for sensitivity. In cases where the microorganism is found to be sensitive, ciprofloxacin can be considered as a suitable alternative.

The patient in this case has been diagnosed with type 1 autoimmune hepatitis, also known as classic type autoimmune hepatitis. This condition is characterized by inflammation of the liver due to reduced levels of regulatory T-cells (Treg cells), leading to the production of autoantibodies against hepatocyte surface antigens. It primarily affects women (70%) between the ages of 15 and 40.

Autoimmune hepatitis causes chronic and progressive hepatitis, which eventually progresses to cirrhosis. Patients typically experience non-specific symptoms of malaise, but in some cases, the disease may present in its later stages with jaundice and severe illness. During this stage, liver function tests often show significantly elevated transaminases (ALT and AST), usually more than ten times the normal levels, and a normal or slightly elevated alkaline phosphatase (ALP). Around 80% of cases show positive antinuclear antibodies (ANA), while approximately 70% show positive smooth muscle antibodies (SMA). Antimitochondrial antibodies are usually low or absent.

There are four recognized subtypes of autoimmune hepatitis:
1. Type 1 (Classic type): Positive ANA and SMA, and grossly elevated IgG
2. Type 2: Positive liver kidney microsomal antibodies (affects children)
3. Type 3: Positive soluble liver antigen antibodies
4. Type 4: Seronegative

Treatment for autoimmune hepatitis involves the use of corticosteroids and/or azathioprine. Remission can be achieved in approximately 70% of cases. In some cases where drug therapy is not effective, liver transplantation may be necessary.

Primary sclerosing cholangitis (PSC) is a condition that affects the bile ducts, causing progressive inflammation and obstruction. It is characterized by recurrent episodes of cholangitis and progressive scarring of the bile ducts. PSC can ultimately lead to liver cirrhosis, liver failure, and hepatocellular carcinoma. There is a known association between PSC and ulcerative colitis, with more than 80% of PSC patients also having ulcerative colitis.

Primary biliary cirrhosis (PBC) is an autoimmune disease that results in the progressive destruction of the small bile ducts in the liver, primarily affecting the intralobular ducts. This leads to cholestatic jaundice, liver fibrosis, and eventually cirrhosis. PBC is more common in females (90%)

During CPR of a hypothermic patient, it is important to follow specific guidelines. If the patient’s core temperature is below 30ºC, resuscitation drugs, such as adrenaline, should be withheld. Once the core temperature rises above 30ºC, cardiac arrest drugs can be administered. However, if the patient’s temperature is between 30-35ºC, the interval for administering cardiac arrest drugs should be doubled. For example, adrenaline should be given every 6-10 minutes instead of the usual 3-5 minutes for a normothermic patient.

Further Reading:

Hypothermic cardiac arrest is a rare situation that requires a tailored approach. Resuscitation is typically prolonged, but the prognosis for young, previously healthy individuals can be good. Hypothermic cardiac arrest may be associated with drowning. Hypothermia is defined as a core temperature below 35ºC and can be graded as mild, moderate, severe, or profound based on the core temperature. When the core temperature drops, basal metabolic rate falls and cell signaling between neurons decreases, leading to reduced tissue perfusion. Signs and symptoms of hypothermia progress as the core temperature drops, initially presenting as compensatory increases in heart rate and shivering, but eventually ceasing as the temperature drops into moderate hypothermia territory.

ECG changes associated with hypothermia include bradyarrhythmias, Osborn waves, prolonged PR, QRS, and QT intervals, shivering artifact, ventricular ectopics, and cardiac arrest. When managing hypothermic cardiac arrest, ALS should be initiated as per the standard ALS algorithm, but with modifications. It is important to check for signs of life, re-warm the patient, consider mechanical ventilation due to chest wall stiffness, adjust dosing or withhold drugs due to slowed drug metabolism, and correct electrolyte disturbances. The resuscitation of hypothermic patients is often prolonged and may continue for a number of hours.

Pulse checks during CPR may be difficult due to low blood pressure, and the pulse check is prolonged to 1 minute for this reason. Drug metabolism is slowed in hypothermic patients, leading to a build-up of potentially toxic plasma concentrations of administered drugs. Current guidance advises withholding drugs if the core temperature is below 30ºC and doubling the drug interval at core temperatures between 30 and 35ºC. Electrolyte disturbances are common in hypothermic patients, and it is important to interpret results keeping the setting in mind. Hypoglycemia should be treated, hypokalemia will often correct as the patient re-warms, ABG analyzers may not reflect the reality of the hypothermic patient, and severe hyperkalemia is a poor prognostic indicator.

Different warming measures can be used to increase the core body temperature, including external passive measures such as removal of wet clothes and insulation with blankets, external active measures such as forced heated air or hot-water immersion, and internal active measures such as inhalation of warm air, warmed intravenous fluids, gastric, bladder, peritoneal and/or pleural lavage and high volume renal haemofilter.

The Insall-Salvati ratio is determined by dividing the length of the patellar tendon (TL) by the length of the patella (PL). This ratio is used to compare the relative lengths of these two structures. A normal ratio is typically 1:1.

Further Reading:

A quadriceps tendon tear or rupture is a traumatic lower limb and joint injury that occurs when there is heavy loading on the leg, causing forced contraction of the quadriceps while the foot is planted and the knee is partially bent. These tears most commonly happen at the osteotendinous junction between the tendon and the superior pole of the patella. Quadriceps tendon ruptures are more common than patellar tendon ruptures.

When a quadriceps tendon tear occurs, the patient usually experiences a tearing sensation and immediate pain. They will then typically complain of pain around the knee and over the tendon. Clinically, there will often be a knee effusion and weakness or inability to actively extend the knee.

In cases of complete quadriceps tears, the patella will be displaced distally, resulting in a low lying patella or patella infera, also known as patella baja. Radiological measurements, such as the Insall-Salvati ratio, can be used to measure patella height. The Insall-Salvati ratio is calculated by dividing the patellar tendon length by the patellar length. A normal ratio is between 0.8 to 1.2, while a low lying patella (patella baja) is less than 0.8 and a high lying patella (patella alta) is greater than 1.2.

In pediatric patients who have sustained burns in a house fire, the presence of burns greater than 15% of the total body surface area should trigger the initiation of immediate fluid resuscitation.

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.

Acute mastoiditis commonly occurs as a complication of acute otitis media (AOM). In this case, the patient exhibits symptoms indicative of acute mastoiditis. The infection typically spreads from the middle ear tympanic cavity (acute otitis media) to the mastoid antrum through a narrow canal within the petrous temporal bone.

Further Reading:

Mastoiditis is an infection of the mastoid air cells, which are located in the mastoid process of the skull. It is usually caused by the spread of infection from the middle ear. The most common organism responsible for mastoiditis is Streptococcus pneumoniae, but other bacteria and fungi can also be involved. The infection can spread to surrounding structures, such as the meninges, causing serious complications like meningitis or cerebral abscess.

Mastoiditis can be classified as acute or chronic. Acute mastoiditis is a rare complication of acute otitis media, which is inflammation of the middle ear. It is characterized by severe ear pain, fever, swelling and redness behind the ear, and conductive deafness. Chronic mastoiditis is usually associated with chronic suppurative otitis media or cholesteatoma and presents with recurrent episodes of ear pain, headache, and fever.

Mastoiditis is more common in children, particularly those between 6 and 13 months of age. Other risk factors include immunocompromised patients, those with intellectual impairment or communication difficulties, and individuals with cholesteatoma.

Diagnosis of mastoiditis involves a physical examination, blood tests, ear swab for culture and sensitivities, and imaging studies like contrast-enhanced CT or MRI. Treatment typically involves referral to an ear, nose, and throat specialist, broad-spectrum intravenous antibiotics, pain relief, and myringotomy (a procedure to drain fluid from the middle ear).

Complications of mastoiditis are rare but can be serious. They include intracranial abscess, meningitis, subperiosteal abscess, neck abscess, venous sinus thrombosis, cranial nerve palsies, hearing loss, labyrinthitis, extension to the zygoma, and carotid artery arteritis. However, most patients with mastoiditis have a good prognosis and do not experience long-term ear problems.

Post myocardial infarction ventricular septal defect (VSD) is a rare but serious complication that occurs when the cardiac wall ruptures. It typically develops 2-3 days after a heart attack, and if left untreated, 85% of patients will die within two months. The murmur associated with VSD is a continuous sound throughout systole, and it is loudest at the lower left sternal edge. A palpable vibration, known as a thrill, is often felt along with the murmur.

Dressler’s syndrome, on the other hand, is a type of pericarditis that occurs 2-10 weeks after a heart attack or cardiac surgery. It is characterized by sharp chest pain that is relieved by sitting forwards. Other signs of Dressler’s syndrome include a rubbing sound heard when listening to the heart, pulsus paradoxus (an abnormal drop in blood pressure during inspiration), and signs of right ventricular failure.

Mitral regurgitation also causes a continuous murmur throughout systole, but it is best heard at the apex of the heart and may radiate to the axilla (armpit).

Tricuspid stenosis, on the other hand, causes an early diastolic murmur that is best heard at the lower left sternal edge during inspiration.

Lastly, mitral stenosis causes a rumbling mid-diastolic murmur that is best heard at the apex of the heart. To listen for this murmur, the patient should be in the left lateral position, and the stethoscope bell should be used during expiration.

The count of lymphocytes, a type of white blood cell, can serve as an early indication of the level of radiation exposure. The severity of the exposure can be determined by observing the decrease in lymphocyte count, which is directly related to the amount of radiation absorbed by the body. Ideally, the count is measured 12 hours after exposure and then repeated every 4 hours initially to track the rate of decrease.

Further Reading:

Radiation exposure refers to the emission or transmission of energy in the form of waves or particles through space or a material medium. There are two types of radiation: ionizing and non-ionizing. Non-ionizing radiation, such as radio waves and visible light, has enough energy to move atoms within a molecule but not enough to remove electrons from atoms. Ionizing radiation, on the other hand, has enough energy to ionize atoms or molecules by detaching electrons from them.

There are different types of ionizing radiation, including alpha particles, beta particles, gamma rays, and X-rays. Alpha particles are positively charged and consist of 2 protons and 2 neutrons from the atom’s nucleus. They are emitted from the decay of heavy radioactive elements and do not travel far from the source atom. Beta particles are small, fast-moving particles with a negative electrical charge that are emitted from an atom’s nucleus during radioactive decay. They are more penetrating than alpha particles but less damaging to living tissue. Gamma rays and X-rays are weightless packets of energy called photons. Gamma rays are often emitted along with alpha or beta particles during radioactive decay and can easily penetrate barriers. X-rays, on the other hand, are generally lower in energy and less penetrating than gamma rays.

Exposure to ionizing radiation can damage tissue cells by dislodging orbital electrons, leading to the generation of highly reactive ion pairs. This can result in DNA damage and an increased risk of future malignant change. The extent of cell damage depends on factors such as the type of radiation, time duration of exposure, distance from the source, and extent of shielding.

The absorbed dose of radiation is directly proportional to time, so it is important to minimize the amount of time spent in the vicinity of a radioactive source. A lethal dose of radiation without medical management is 4.5 sieverts (Sv) to kill 50% of the population at 60 days. With medical management, the lethal dose is 5-6 Sv. The immediate effects of ionizing radiation can range from radiation burns to radiation sickness, which is divided into three main syndromes: hematopoietic, gastrointestinal, and neurovascular. Long-term effects can include hematopoietic cancers and solid tumor formation.

In terms of management, support is mainly supportive and includes IV fluids, antiemetics, analgesia, nutritional support, antibiotics, blood component substitution, and reduction of brain edema.

Nephrogenic diabetes insipidus may develop in a certain percentage of individuals who take lithium.

Further Reading:

Diabetes insipidus (DI) is a condition characterized by either a decrease in the secretion of antidiuretic hormone (cranial DI) or insensitivity to antidiuretic hormone (nephrogenic DI). Antidiuretic hormone, also known as arginine vasopressin, is produced in the hypothalamus and released from the posterior pituitary. The typical biochemical disturbances seen in DI include elevated plasma osmolality, low urine osmolality, polyuria, and hypernatraemia.

Cranial DI can be caused by various factors such as head injury, CNS infections, pituitary tumors, and pituitary surgery. Nephrogenic DI, on the other hand, can be genetic or result from electrolyte disturbances or the use of certain drugs. Symptoms of DI include polyuria, polydipsia, nocturia, signs of dehydration, and in children, irritability, failure to thrive, and fatigue.

To diagnose DI, a 24-hour urine collection is done to confirm polyuria, and U&Es will typically show hypernatraemia. High plasma osmolality with low urine osmolality is also observed. Imaging studies such as MRI of the pituitary, hypothalamus, and surrounding tissues may be done, as well as a fluid deprivation test to evaluate the response to desmopressin.

Management of cranial DI involves supplementation with desmopressin, a synthetic form of arginine vasopressin. However, hyponatraemia is a common side effect that needs to be monitored. In nephrogenic DI, desmopressin supplementation is usually not effective, and management focuses on ensuring adequate fluid intake to offset water loss and monitoring electrolyte levels. Causative drugs need to be stopped, and there is a risk of developing complications such as hydroureteronephrosis and an overdistended bladder.

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 this case, the patient has already received two doses of benzodiazepine and is currently on a phenytoin infusion. However, despite these treatments, the seizures persist, and it has been 20 minutes since the infusion started. At this point, the preferred treatment option is to induce general anesthesia. The induction agents that can be considered include thiopental sodium, propofol, and midazolam. There is no need to administer intravenous thiamine in this situation.

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 access

2nd stage (0-30 minutes):
– Implement regular monitoring
– Consider the possibility of non-epileptic status
– Initiate emergency antiepileptic drug (AED) therapy
– Perform emergency investigations
– Administer glucose or intravenous thiamine if alcohol abuse or impaired nutrition is suspected
– Treat severe acidosis if present

3rd stage (0-60 minutes):
– Determine the underlying cause of status epilepticus
– Notify the anesthetist and intensive care unit (ITU)
– Identify and treat any medical complications
– Consider pressor therapy if necessary

4th stage (30-90 minutes):
– Transfer the patient to the intensive care unit
– Establish intensive care and EEG monitoring
– Initiate long-term maintenance AED therapy
– Perform further investigations as needed, such as brain imaging or lumbar puncture

Emergency investigations include blood tests for gases, glucose, renal and liver function, calcium and magnesium levels, 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 convulsive status epilepticus is uncertain. A chest radiograph may be done to evaluate the possibility of aspiration. Additional investigations depend on the clinical circumstances and may include brain imaging or lumbar puncture.

Monitoring during the management of status epilepticus involves regular neurological observations and measurements of pulse, blood pressure, and temperature.

Abducens nerve palsy is often linked to extradural hematoma. When there is a mass effect, downward brain herniation can occur, leading to the involvement of the 6th cranial nerve (abducens nerve, CN VI). This nerve controls the lateral rectus muscle, which is responsible for eye abduction. When the abducens nerve is affected, the lateral rectus muscle is unable to function properly, resulting in an inward turning of the affected eye towards the nose (esotropia).

Further Reading:

Extradural haematoma (EDH) is a collection of blood that forms between the inner surface of the skull and the outer layer of the dura, the dura mater. It is typically caused by head trauma and is often associated with a skull fracture, with the pterion being the most common site of injury. The middle meningeal artery is the most common source of bleeding in EDH.

Clinical features of EDH include a history of head injury with transient loss of consciousness, followed by a lucid interval and gradual loss of consciousness. Other symptoms may include severe headache, sixth cranial nerve palsies, nausea and vomiting, seizures, signs of raised intracranial pressure, and focal neurological deficits.

Imaging of EDH typically shows a biconvex shape and may cause mass effect with brain herniation. It can be differentiated from subdural haematoma by its appearance on imaging.

Management of EDH involves prompt referral to neurosurgery for evacuation of the haematoma. In some cases with a small EDH, conservative management may be considered. With prompt evacuation, the prognosis for EDH is generally good.

The symptoms observed in the casualties of this CBRN event strongly indicate exposure to a nerve agent. Among the options provided, VX gas is the only nerve agent listed, making it the most likely culprit.

Nerve agents, also known as nerve gases, are a highly toxic group of chemical warfare agents that were developed just before and during World War II. The initial compounds in this category, known as the G agents, were discovered and synthesized by German scientists. They include Tabun (GA), Sarin (GB), and Soman (GD). In the 1950s, the V agents, which are approximately 10 times more poisonous than Sarin, were synthesized. 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 a nerve agent was the Tokyo subway sarin attack in March 1995. During this attack, Sarin was released into the Tokyo subway system during rush hour, resulting in over 5,000 people seeking medical attention. Among them, 984 were moderately poisoned, 54 were severely poisoned, and 12 lost their lives.

Nerve agents are organophosphorus esters that are chemically related to organophosphorus insecticides. They work by inhibiting acetylcholinesterase (AChE), an enzyme responsible for breaking down the neurotransmitter acetylcholine (ACh). This inhibition 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 enter the body through the skin, eyes, and respiratory tract. In vapor form, they are primarily absorbed through the respiratory tract and eyes. If a sufficient amount of the agent is absorbed, it can cause local effects followed by systemic effects throughout the body.

The clinical symptoms observed after exposure to nerve agents are a result of the combined effects on the muscarinic, nicotinic, and central nervous systems. Muscarinic effects, often remembered using the acronym DUMBBELS, include diarrhea, urination, miosis (constriction of the pupils), bronchorrhea (excessive mucus production in the airways), bronchospasm (narrowing of the airways), emesis (vomiting), lacrimation (excessive tearing), and salivation.

Adenosine is a type of purine nucleoside that is primarily utilized in the diagnosis and treatment of paroxysmal supraventricular tachycardia. Its main mechanism of action involves stimulating A1-adenosine receptors and opening acetylcholine-sensitive potassium channels. This leads to hyperpolarization of the cell membrane in the atrioventricular (AV) node and slows down conduction in the AV node by inhibiting calcium channels.

When administering adenosine, it is given rapidly through an intravenous bolus, followed by a saline flush. The initial dose for adults is 6 mg, and if necessary, additional doses of 12 mg or 18 mg can be given at 1-2 minute intervals until the desired effect is observed. It is important to note that the latest ALS guidelines recommend 18 mg for the third dose, while the BNF/NICE guidelines suggest 12 mg.

One of the advantages of adenosine is its very short half-life, which is less than 10 seconds. This means that its effects are rapid, typically occurring within 10 seconds. However, the duration of action is also short, lasting only 10-20 seconds. Due to its short half-life, any side effects experienced are usually brief. These side effects may include a sense of impending doom, facial flushing, dyspnea, chest discomfort, and a metallic taste.

There are certain contraindications to the use of adenosine. These include 2nd or 3rd degree AV block, sick sinus syndrome, long QT syndrome, severe hypotension, decompensated heart failure, chronic obstructive lung disease, and asthma. It is important to exercise caution when administering adenosine to patients with a heart transplant, as they are particularly sensitive to its effects. In these cases, a reduced initial dose of 3 mg is recommended, followed by 6 mg and then 12 mg.

It is worth noting that the effects of adenosine can be potentiated by dipyridamole, a medication commonly used in combination with adenosine. Therefore, the dose of adenosine should be adjusted and reduced in patients who are also taking dipyridamole.

The recommended dose of activated charcoal for adults and children aged 12 or over to prevent the absorption of poisons in the gastrointestinal tract is 50g.

Further Reading:

Paracetamol poisoning occurs when the liver is unable to metabolize paracetamol properly, leading to the production of a toxic metabolite called N-acetyl-p-benzoquinone imine (NAPQI). Normally, NAPQI is conjugated by glutathione into a non-toxic form. However, during an overdose, the liver’s conjugation systems become overwhelmed, resulting in increased production of NAPQI and depletion of glutathione stores. This leads to the formation of covalent bonds between NAPQI and cell proteins, causing cell death in the liver and kidneys.

Symptoms of paracetamol poisoning may not appear for the first 24 hours or may include abdominal symptoms such as nausea and vomiting. After 24 hours, hepatic necrosis may develop, leading to elevated liver enzymes, right upper quadrant pain, and jaundice. Other complications can include encephalopathy, oliguria, hypoglycemia, renal failure, and lactic acidosis.

The management of paracetamol overdose depends on the timing and amount of ingestion. Activated charcoal may be given if the patient presents within 1 hour of ingesting a significant amount of paracetamol. N-acetylcysteine (NAC) is used to increase hepatic glutathione production and is given to patients who meet specific criteria. Blood tests are taken to assess paracetamol levels, liver function, and other parameters. Referral to a medical or liver unit may be necessary, and psychiatric follow-up should be considered for deliberate overdoses.

In cases of staggered ingestion, all patients should be treated with NAC without delay. Blood tests are also taken, and if certain criteria are met, NAC can be discontinued. Adverse reactions to NAC are common and may include anaphylactoid reactions, rash, hypotension, and nausea. Treatment for adverse reactions involves medications such as chlorpheniramine and salbutamol, and the infusion may be stopped if necessary.

The prognosis for paracetamol poisoning can be poor, especially in cases of severe liver injury. Fulminant liver failure may occur, and liver transplant may be necessary. Poor prognostic indicators include low arterial pH, prolonged prothrombin time, high plasma creatinine, and hepatic encephalopathy.