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.

Crohn’s disease is characterized by skip lesions, which are not present in ulcerative colitis. Unlike ulcerative colitis, Crohn’s disease causes inflammation throughout the entire thickness of the intestinal wall, not just the mucosa. Interestingly, smoking increases the risk of developing Crohn’s disease but decreases the risk of ulcerative colitis. Additionally, having an appendicectomy before adulthood is believed to protect against ulcerative colitis, whereas it actually increases the risk of developing Crohn’s disease for about 5 years after the surgery.

Further Reading:

Inflammatory bowel disease (IBD) is a chronic condition characterized by inflammation of the intestinal tract and an imbalance of the intestinal microbiota. The two main forms of IBD are Crohn’s disease and ulcerative colitis (UC). In some cases, it is not possible to differentiate between Crohn’s disease and UC, and the term inflammatory bowel disease type-unclassified may be used.

Crohn’s disease is a chronic, relapsing-remitting inflammatory disease that can affect any part of the gastrointestinal tract, from the mouth to the anus. It most commonly involves the ileum and colon. The inflammation in Crohn’s disease affects all layers of the intestinal wall, leading to complications such as strictures, fistulas, and adhesions. Risk factors for developing Crohn’s disease include a family history, smoking, infectious gastroenteritis, appendicectomy, and the use of NSAIDs and oral contraceptive drugs. Symptoms of Crohn’s disease can vary but often include diarrhea, abdominal pain, weight loss, and perianal disease. Extraintestinal features, such as arthritis, erythema nodosum, and uveitis, can also occur.

Ulcerative colitis is a chronic, relapsing-remitting inflammatory disease that primarily affects the large bowel. The inflammation in UC is limited to the intestinal mucosa and does not involve skip lesions like in Crohn’s disease. Risk factors for developing UC include a family history, not smoking, and no appendix. Symptoms of UC include bloody diarrhea, urgency, tenesmus, and abdominal pain. Extraintestinal features, such as arthritis and uveitis, can also occur. Complications of UC include toxic megacolon, bowel obstruction, bowel perforation, strictures, fistula formation, anemia, malnutrition, and colorectal cancer.

Diagnosing IBD involves various investigations, including blood tests, stool microscopy and culture, fecal calprotectin testing, endoscopy with biopsy, and imaging modalities such as CT and MR enterography. The management of Crohn’s disease and UC is complex and may involve corticosteroids, immunosuppressive drugs, biologic therapy, surgery, and nutritional support. Patients with IBD should also be monitored for nutritional deficiencies, colorectal cancer, and osteoporosis.

Patients who have myxoedema coma usually show symptoms such as lethargy, bradycardia, hypothermia, worsening mental state, seizures, and/or coma. This patient has hypothyroidism and takes thyroxine regularly, which aligns with the signs and symptoms of myxoedema coma. It is worth noting that infections often act as a trigger, and this patient has developed a cough in the last week.

Further Reading:

The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.

Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.

The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.

Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.

Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.

Testicular cancer is the most common form of cancer that affects men between the ages of 20 and 34. In recent times, there have been campaigns aimed at raising awareness about the importance of self-examination for early detection. Some risk factors for this type of cancer include having undescended testes, especially if it affects both testicles, which increases the risk by ten times. Additionally, individuals who have had testicular cancer in the past have a 4% chance of developing a second cancer.

The typical presentation of testicular cancer is a painless swelling in the testicles. When examined, the swelling feels hard and is located within the testis. It cannot be illuminated when light is shone through it. Approximately 60% of cases are seminomas, which are slow-growing and usually confined to the testis at the time of diagnosis. If seminomas are diagnosed at stage 1 (confined to the testis only), the 5-year survival rate is 98%. The remaining 40% of cases are teratomas, which can grow at a faster rate and often coexist with seminomas. In cases where the tumors are of mixed type, they are treated as teratomas due to their more aggressive nature. The main treatment for testicular cancer is surgery, with the possibility of additional chemotherapy and radiotherapy.

Hepatic encephalopathy is a condition caused by the accumulation of nitrogenous waste products in the body due to impaired liver function. These waste products cross the blood brain barrier and contribute to the production of glutamine, leading to changes in astrocyte osmotic pressure, brain edema, and neurotransmitter dysfunction.

To address hepatic encephalopathy, the first-line drugs used are Rifaximin and lactulose. Rifaximin is an oral antibiotic that helps reduce the presence of ammonia-producing bacteria in the intestines. Lactulose, on the other hand, converts soluble ammonia into insoluble ammonium and aids in relieving constipation.

It is important to note that Chlordiazepoxide, a benzodiazepine, may be used to treat alcohol withdrawal but should be avoided in cases of hepatic encephalopathy as it can worsen the condition.

Further Reading:

Cirrhosis is a condition where the liver undergoes structural changes, resulting in dysfunction of its normal functions. It can be classified as either compensated or decompensated. Compensated cirrhosis refers to a stage where the liver can still function effectively with minimal symptoms, while decompensated cirrhosis is when the liver damage is severe and clinical complications are present.

Cirrhosis develops over a period of several years due to repeated insults to the liver. Risk factors for cirrhosis include alcohol misuse, hepatitis B and C infection, obesity, type 2 diabetes, autoimmune liver disease, genetic conditions, certain medications, and other rare conditions.

The prognosis of cirrhosis can be assessed using the Child-Pugh score, which predicts mortality based on parameters such as bilirubin levels, albumin levels, INR, ascites, and encephalopathy. The score ranges from A to C, with higher scores indicating a poorer prognosis.

Complications of cirrhosis include portal hypertension, ascites, hepatic encephalopathy, variceal hemorrhage, increased infection risk, hepatocellular carcinoma, and cardiovascular complications.

Diagnosis of cirrhosis is typically done through liver function tests, blood tests, viral hepatitis screening, and imaging techniques such as transient elastography or acoustic radiation force impulse imaging. Liver biopsy may also be performed in some cases.

Management of cirrhosis involves treating the underlying cause, controlling risk factors, and monitoring for complications. Complications such as ascites, spontaneous bacterial peritonitis, oesophageal varices, and hepatic encephalopathy require specific management strategies.

Overall, cirrhosis is a progressive condition that requires ongoing monitoring and management to prevent further complications and improve outcomes for patients.

Recognizing the extent of blood loss based on vital sign and mental status abnormalities is a crucial skill. The Advanced Trauma Life Support (ATLS) classification for hemorrhagic shock correlates the amount of blood loss with expected physiological responses in a healthy individual weighing 70 kg. In terms of body weight, the total circulating blood volume accounts for approximately 7%, which is roughly equivalent to five liters in an average 70 kg male patient.

The ATLS classification for hemorrhagic shock is as follows:

CLASS I:
– Blood loss: Up to 750 mL
– Blood loss (% blood volume): Up to 15%
– Pulse rate: Less than 100 beats per minute (bpm)
– Systolic blood pressure: Normal
– Pulse pressure: Normal (or increased)
– Respiratory rate: 14-20 breaths per minute
– Urine output: Greater than 30 mL/hr
– CNS/mental status: Slightly anxious

CLASS II:
– Blood loss: 750-1500 mL
– Blood loss (% blood volume): 15-30%
– Pulse rate: 100-120 bpm
– Systolic blood pressure: Normal
– Pulse pressure: Decreased
– Respiratory rate: 20-30 breaths per minute
– Urine output: 20-30 mL/hr
– CNS/mental status: Mildly anxious

CLASS III:
– Blood loss: 1500-2000 mL
– Blood loss (% blood volume): 30-40%
– Pulse rate: 120-140 bpm
– Systolic blood pressure: Decreased
– Pulse pressure: Decreased
– Respiratory rate: 30-40 breaths per minute
– Urine output: 5-15 mL/hr
– CNS/mental status: Anxious, confused

CLASS IV:
– Blood loss: More than 2000 mL
– Blood loss (% blood volume): More than 40%
– Pulse rate: More than 140 bpm
– Systolic blood pressure: Decreased
– Pulse pressure: Decreased
– Respiratory rate: More than 40 breaths per minute
– Urine output: Negligible
– CNS/mental status: Confused, lethargic

Mitral regurgitation is characterized by several clinical features. One of the main signs is a pansystolic murmur that can be heard throughout the entire systolic phase of the cardiac cycle. This murmur often radiates to the left axilla. Another notable feature is a soft S1 heart sound, which is the first heart sound heard during the cardiac cycle. Additionally, a 3rd heart sound, also known as an added sound, can be detected in patients with mitral regurgitation. As the condition progresses to moderate to severe levels, signs such as a laterally displaced apex beat with a heave may become apparent.

Further Reading:

Mitral Stenosis:
– Causes: Rheumatic fever, Mucopolysaccharidoses, Carcinoid, Endocardial fibroelastosis
– Features: Mid-late diastolic murmur, loud S1, opening snap, low volume pulse, malar flush, atrial fibrillation, signs of pulmonary edema, tapping apex beat
– Features of severe mitral stenosis: Length of murmur increases, opening snap becomes closer to S2
– Investigation findings: CXR may show left atrial enlargement, echocardiography may show reduced cross-sectional area of the mitral valve

Mitral Regurgitation:
– Causes: Mitral valve prolapse, Myxomatous degeneration, Ischemic heart disease, Rheumatic fever, Connective tissue disorders, Endocarditis, Dilated cardiomyopathy
– Features: pansystolic murmur radiating to left axilla, soft S1, S3, laterally displaced apex beat with heave
– Signs of acute MR: Decompensated congestive heart failure symptoms
– Signs of chronic MR: Leg edema, fatigue, arrhythmia (atrial fibrillation)
– Investigation findings: Doppler echocardiography to detect regurgitant flow and pulmonary hypertension, ECG may show signs of LA enlargement and LV hypertrophy, CXR may show LA and LV enlargement in chronic MR and pulmonary edema in acute MR.

Urinary alkalinisation aims to achieve a urinary pH of 7.5-8.5. This process helps enhance the elimination of salicylates. It is important to regularly monitor urinary pH, ideally on an hourly basis.

Further Reading:

Salicylate poisoning, particularly from aspirin overdose, is a common cause of poisoning in the UK. One important concept to understand is that salicylate overdose leads to a combination of respiratory alkalosis and metabolic acidosis. Initially, the overdose stimulates the respiratory center, leading to hyperventilation and respiratory alkalosis. However, as the effects of salicylate on lactic acid production, breakdown into acidic metabolites, and acute renal injury occur, it can result in high anion gap metabolic acidosis.

The clinical features of salicylate poisoning include hyperventilation, tinnitus, lethargy, sweating, pyrexia (fever), nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.

When investigating salicylate poisoning, it is important to measure salicylate levels in the blood. The sample should be taken at least 2 hours after ingestion for symptomatic patients or 4 hours for asymptomatic patients. The measurement should be repeated every 2-3 hours until the levels start to decrease. Other investigations include arterial blood gas analysis, electrolyte levels (U&Es), complete blood count (FBC), coagulation studies (raised INR/PTR), urinary pH, and blood glucose levels.

To manage salicylate poisoning, an ABC approach should be followed to ensure a patent airway and adequate ventilation. Activated charcoal can be administered if the patient presents within 1 hour of ingestion. Oral or intravenous fluids should be given to optimize intravascular volume. Hypokalemia and hypoglycemia should be corrected. Urinary alkalinization with intravenous sodium bicarbonate can enhance the elimination of aspirin in the urine. In severe cases, hemodialysis may be necessary.

Urinary alkalinization involves targeting a urinary pH of 7.5-8.5 and checking it hourly. It is important to monitor for hypokalemia as alkalinization can cause potassium to shift from plasma into cells. Potassium levels should be checked every 1-2 hours.

In cases where the salicylate concentration is high (above 500 mg/L in adults or 350 mg/L in children), sodium bicarbonate can be administered intravenously. Hemodialysis is the treatment of choice for severe poisoning and may be indicated in cases of high salicylate levels, resistant metabolic acidosis, acute kidney injury, pulmonary edema, seizures and coma.

This patient is highly likely to have developed a tubo-ovarian abscess (TOA), which is a complication of pelvic inflammatory disease. TOA occurs when a pocket of pus forms in the fallopian tube and/or ovary. If the abscess ruptures, it can lead to sepsis and become life-threatening.

The initial imaging modality of choice is transabdominal and endovaginal ultrasound. This imaging technique often reveals multilocular complex retro-uterine/adnexal masses with debris, septations, and irregular thick walls. These masses can be present on both sides.

Urgent hospital admission is necessary, and the usual management involves draining the abscess and administering intravenous antibiotics. The abscess drainage can be guided by ultrasound or CT scanning.

In some cases, laparotomy or laparoscopy may be required to drain the abscess.

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.

If a child who is experiencing convulsions reaches step 3 of the APLS algorithm, it is recommended to prepare a phenytoin infusion. This infusion should be administered at a dosage of 20 mg/kg over a period of 20 minutes.

An abnormal QTc, which is the measurement of the time it takes for the heart to recharge between beats, is generally considered to be greater than 450 ms in males. However, some sources may use a cutoff of greater than 440 ms as abnormal in males. To further categorize the QTc, a measurement of 430ms or less is considered normal, 431-450 ms is borderline, and 450 ms or more is considered abnormal in males. Females typically have a longer QTc, so the categories for them are often quoted as less than 450 ms being normal, 451-470 ms being borderline, and greater than 470ms being abnormal.

Further Reading:

Long QT syndrome (LQTS) is a condition characterized by a prolonged QT interval on an electrocardiogram (ECG), which represents abnormal repolarization of the heart. LQTS can be either acquired or congenital. Congenital LQTS is typically caused by gene abnormalities that affect ion channels responsible for potassium or sodium flow in the heart. There are 15 identified genes associated with congenital LQTS, with three genes accounting for the majority of cases. Acquired LQTS can be caused by various factors such as certain medications, electrolyte imbalances, hypothermia, hypothyroidism, and bradycardia from other causes.

The normal QTc values, which represent the corrected QT interval for heart rate, are typically less than 450 ms for men and less than 460ms for women. Prolonged QTc intervals are considered to be greater than these values. It is important to be aware of drugs that can cause QT prolongation, as this can lead to potentially fatal arrhythmias. Some commonly used drugs that can cause QT prolongation include antimicrobials, antiarrhythmics, antipsychotics, antidepressants, antiemetics, and others.

Management of long QT syndrome involves addressing any underlying causes and using beta blockers. In some cases, an implantable cardiac defibrillator (ICD) may be recommended for patients who have experienced recurrent arrhythmic syncope, documented torsades de pointes, previous ventricular tachyarrhythmias or torsades de pointes, previous cardiac arrest, or persistent syncope. Permanent pacing may be used in patients with bradycardia or atrioventricular nodal block and prolonged QT. Mexiletine is a treatment option for those with LQT3. Cervicothoracic sympathetic denervation may be considered in patients with recurrent syncope despite beta-blockade or in those who are not ideal candidates for an ICD. The specific treatment options for LQTS depend on the type and severity of the condition.

Patients who have acute otitis media (AOM) and are immunocompromised or systemically unwell should be given an immediate prescription for antibiotics. However, for most patients with AOM, antibiotics are not necessary or can be delayed. An immediate antibiotic prescription should be offered to patients who are systemically unwell but do not require hospitalization, patients at high risk of complications due to underlying health conditions, and patients whose symptoms have persisted for four days or more without improvement. The recommended first choice antibiotic for AOM is amoxicillin.

Further Reading:

Acute otitis media (AOM) is an inflammation in the middle ear accompanied by symptoms and signs of an ear infection. It is commonly seen in young children below 4 years of age, with the highest incidence occurring between 9 to 15 months of age. AOM can be caused by viral or bacterial pathogens, and co-infection with both is common. The most common viral pathogens include respiratory syncytial virus (RSV), rhinovirus, adenovirus, influenza virus, and parainfluenza virus. The most common bacterial pathogens include Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pyogenes.

Clinical features of AOM include ear pain (otalgia), fever, a red or cloudy tympanic membrane, and a bulging tympanic membrane with loss of anatomical landmarks. In young children, symptoms may also include crying, grabbing or rubbing the affected ear, restlessness, and poor feeding.

Most children with AOM will recover within 3 days without treatment. Serious complications are rare but can include persistent otitis media with effusion, recurrence of infection, temporary hearing loss, tympanic membrane perforation, labyrinthitis, mastoiditis, meningitis, intracranial abscess, sinus thrombosis, and facial nerve paralysis.

Management of AOM involves determining whether admission to the hospital is necessary based on the severity of systemic infection or suspected acute complications. For patients who do not require admission, regular pain relief with paracetamol or ibuprofen is advised. Decongestants or antihistamines are not recommended. Antibiotics may be offered immediately for patients who are systemically unwell, have symptoms and signs of a more serious illness or condition, or have a high risk of complications. For other patients, a decision needs to be made on the antibiotic strategy, considering the rarity of acute complications and the possible adverse effects of antibiotics. Options include no antibiotic prescription with advice to seek medical help if symptoms worsen rapidly or significantly, a back-up antibiotic prescription to be used if symptoms do not improve within 3 days, or an immediate antibiotic prescription with advice to seek medical advice if symptoms worsen rapidly or significantly.

The first-line antibiotic choice for AOM is a 5-7 day course of amoxicillin. For individuals allergic to or intolerant of penicillin, clarithromycin or erythromycin a 5–7 day course of clarithromycin or erythromycin (erythromycin is preferred in pregnant women).

Osgood-Schlatter disease is commonly observed in active teenagers and is characterized by pain and tenderness in the tibial tuberosity. Rest is typically recommended as part of the treatment plan, and the diagnosis is made based on clinical evaluation.

Chondromalacia patella is most prevalent in teenage girls and is often accompanied by knee pain while going up and downstairs. Discomfort tends to worsen after prolonged periods of sitting. Treatment options include pain relief medication and physiotherapy.

Prepatellar bursitis, also known as housemaid’s knee, is linked to excessive kneeling.

Pseudogout is an inflammatory arthritis caused by the accumulation of pyrophosphate crystals. While the knees are frequently affected, it is unlikely to occur in this age group.

Still’s disease accounts for approximately 10% of cases of juvenile chronic arthritis. It typically involves multiple systems in the body and is often characterized by fever, rash, swollen lymph nodes, and joint pain.

The use of low-dose aspirin during pregnancy is considered safe and can be used to manage recurrent miscarriage, clotting disorders, and pre-eclampsia. On the other hand, high-dose aspirin carries several risks, especially if used in the third trimester. These risks include delayed onset of labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus (a condition that affects the brain due to high levels of bilirubin). Additionally, there is a slight increase in the risk of first-trimester abortion if high-dose aspirin is used early in pregnancy.

Below is a list outlining commonly encountered drugs that have adverse effects during pregnancy:

Drug: ACE inhibitors (e.g. ramipril)
Adverse effects: If given in the second and third trimester, ACE inhibitors can cause hypoperfusion, renal failure, and the oligohydramnios sequence.

Drug: Aminoglycosides (e.g. gentamicin)
Adverse effects: Aminoglycosides can cause ototoxicity (damage to the ear) and deafness.

Drug: Aspirin
Adverse effects: High doses of aspirin can cause first-trimester abortions, delayed onset of labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses (e.g. 75 mg) have no significant associated risk.

Thyroid storm is a rare condition that affects only 1-2% of patients with hyperthyroidism. However, it is crucial to diagnose it promptly because it has a high mortality rate of approximately 10%. Thyroid storm is often triggered by a physiological stressor, such as stopping antithyroid therapy prematurely, recent surgery or radio-iodine treatment, infections (especially chest infections), trauma, diabetic ketoacidosis or hyperosmolar diabetic crisis, thyroid hormone overdose, pre-eclampsia. It typically occurs in patients with Graves’ disease or toxic multinodular goitre and presents with sudden and severe hyperthyroidism. Symptoms include high fever (over 41°C), dehydration, rapid heart rate (greater than 140 beats per minute) with or without irregular heart rhythms, low blood pressure, congestive heart failure, nausea, jaundice, vomiting, diarrhea, abdominal pain, confusion, agitation, delirium, psychosis, seizures, or coma.

To diagnose thyroid storm, various blood tests should be conducted, including a full blood count, urea and electrolytes, blood glucose, coagulation screen, CRP, and thyroid profile (T4/T3 and TSH). A bone profile/calcium test should also be done as 10% of patients develop hypocalcemia. Blood cultures should be taken as well. Other important investigations include a urine dipstick/MC&S, chest X-ray, and ECG.

The management of thyroid storm involves several steps. Intravenous fluids, such as 1-2 liters of 0.9% saline, should be administered. Airway support and management should be provided as necessary. A nasogastric tube should be inserted if the patient is vomiting. Urgent referral for inpatient management is essential. Paracetamol (1 g PO/IV) can be given to reduce fever. Benzodiazepines, such as diazepam (5-20 mg PO/IV), can be used for sedation. Steroids, like hydrocortisone (100 mg IV), may be necessary if there is co-existing adrenal suppression. Antibiotics should be prescribed if there is an intercurrent infection. Beta-blockers, such as propranolol (80 mg PO), can help control heart rate. High-dose carbimazole (45-60 mg/day) is recommended.

Nelson’s syndrome is a rare condition that occurs many years after a bilateral adrenalectomy for Cushing’s syndrome. It is believed to develop due to the loss of the normal negative feedback control that suppresses high cortisol levels. As a result, the hypothalamus starts producing CRH again, which stimulates the growth of a pituitary adenoma that produces adrenocorticotropic hormone (ACTH).

Only 15-20% of patients who undergo bilateral adrenalectomy will develop this condition, and it is now rarely seen as the procedure is no longer commonly performed.

The symptoms and signs of Nelson’s syndrome are related to the growth of the pituitary adenoma and the increased production of ACTH and melanocyte-stimulating hormone (MSH) from the adenoma. These may include headaches, visual field defects (up to 50% of cases), increased skin pigmentation, and the possibility of hypopituitarism.

ACTH levels will be significantly elevated (usually >500 ng/L). Thyroxine, TSH, gonadotrophin, and sex hormone levels may be low. Prolactin levels may be high, but not as high as with a prolactin-producing tumor. MRI or CT scanning can be helpful in identifying the presence of an expanding pituitary mass.

The treatment of choice for Nelson’s syndrome is trans-sphenoidal surgery.

Atropine and pralidoxime are both considered antidotes for treating organophosphate poisoning. Organophosphates work by inhibiting acetylcholinesterase at nerve synapses. In addition to providing supportive care and administering antidotes, it is important to decontaminate patients as part of their treatment plan for organophosphate poisoning.

While both atropine and pralidoxime are recognized as antidotes, pralidoxime is not commonly used. Atropine works by competing with acetylcholine at the muscarinic receptors. On the other hand, pralidoxime helps reactivate acetylcholinesterase-organophosphate complexes that have not lost an alkyl side chain, known as non-aged complexes. However, pralidoxime is not effective against organophosphates that have already formed or rapidly form aged acetylcholinesterase complexes. The evidence regarding the effectiveness of pralidoxime is conflicting.

Further Reading:

Chemical incidents can occur as a result of leaks, spills, explosions, fires, terrorism, or the use of chemicals during wars. Industrial sites that use chemicals are required to conduct risk assessments and have accident plans in place for such incidents. Health services are responsible for decontamination, unless mass casualties are involved, and all acute health trusts must have major incident plans in place.

When responding to a chemical incident, hospitals prioritize containment of the incident and prevention of secondary contamination, triage with basic first aid, decontamination if not done at the scene, recognition and management of toxidromes (symptoms caused by exposure to specific toxins), appropriate supportive or antidotal treatment, transfer to definitive treatment, a safe end to the hospital response, and continuation of business after the event.

To obtain advice when dealing with chemical incidents, the two main bodies are Toxbase and the National Poisons Information Service. Signage on containers carrying chemicals and material safety data sheets (MSDS) accompanying chemicals also provide information on the chemical contents and their hazards.

Contamination in chemical incidents can occur in three phases: primary contamination from the initial incident, secondary contamination spread via contaminated people leaving the initial scene, and tertiary contamination spread to the environment, including becoming airborne and waterborne. The ideal personal protective equipment (PPE) for chemical incidents is an all-in-one chemical-resistant overall with integral head/visor and hands/feet worn with a mask, gloves, and boots.

Decontamination of contaminated individuals involves the removal and disposal of contaminated clothing, followed by either dry or wet decontamination. Dry decontamination is suitable for patients contaminated with non-caustic chemicals and involves blotting and rubbing exposed skin gently with dry absorbent material. Wet decontamination is suitable for patients contaminated with caustic chemicals and involves a warm water shower while cleaning the body with simple detergent.

After decontamination, the focus shifts to assessing the extent of any possible poisoning and managing it. The patient’s history should establish the chemical the patient was exposed to, the volume and concentration of the chemical, the route of exposure, any protective measures in place, and any treatment given. Most chemical poisonings require supportive care using standard resuscitation principles, while some chemicals have specific antidotes. Identifying toxidromes can be useful in guiding treatment, and specific antidotes may be administered accordingly.

The key initial management for tension pneumothorax is needle thoracocentesis. This procedure is crucial as it rapidly decompresses the tension and allows for more definitive management to be implemented. It is important to note that according to ATLS guidelines, needle thoracocentesis should no longer be performed at the second intercostal space midclavicular line. Studies have shown that the fourth or fifth intercostal space midaxillary line is more successful in reaching the thoracic cavity in adult patients. Therefore, ATLS now recommends this location for needle decompression in adult patients.

Further Reading:

A pneumothorax is an abnormal collection of air in the pleural cavity of the lung. It can be classified by cause as primary spontaneous, secondary spontaneous, or traumatic. Primary spontaneous pneumothorax occurs without any obvious cause in the absence of underlying lung disease, while secondary spontaneous pneumothorax occurs in patients with significant underlying lung diseases. Traumatic pneumothorax is caused by trauma to the lung, often from blunt or penetrating chest wall injuries.

Tension pneumothorax is a life-threatening condition where the collection of air in the pleural cavity expands and compresses normal lung tissue and mediastinal structures. It can be caused by any of the aforementioned types of pneumothorax. Immediate management of tension pneumothorax involves the ABCDE approach, which includes ensuring a patent airway, controlling the C-spine, providing supplemental oxygen, establishing IV access for fluid resuscitation, and assessing and managing other injuries.

Treatment of tension pneumothorax involves needle thoracocentesis as a temporary measure to provide immediate decompression, followed by tube thoracostomy as definitive management. Needle thoracocentesis involves inserting a 14g cannula into the pleural space, typically via the 4th or 5th intercostal space midaxillary line. If the patient is peri-arrest, immediate thoracostomy is advised.

The pathophysiology of tension pneumothorax involves disruption to the visceral or parietal pleura, allowing air to flow into the pleural space. This can occur through an injury to the lung parenchyma and visceral pleura, or through an entry wound to the external chest wall in the case of a sucking pneumothorax. Injured tissue forms a one-way valve, allowing air to enter the pleural space with inhalation but prohibiting air outflow. This leads to a progressive increase in the volume of non-absorbable intrapleural air with each inspiration, causing pleural volume and pressure to rise within the affected hemithorax.

Atropine is a medication that slows down the movement of the digestive system and is not recommended for use in individuals with intestinal blockage. It works by blocking the effects of a neurotransmitter called acetylcholine, which is responsible for promoting gastrointestinal motility and the emptying of the stomach. Therefore, atropine should not be given to patients with gastrointestinal obstruction as it can further hinder the movement of the intestines.

Further Reading:

Types of Heart Block:

1. Atrioventricular (AV) Blocks:
– Disrupt electrical conduction between the atria and ventricles at the AV node.
– Three degrees of AV block: first degree, second degree (type 1 and type 2), and third degree (complete) AV block.

– First degree AV block: PR interval > 0.2 seconds.
– Second degree AV block:
– Type 1 (Mobitz I, Wenckebach): progressive prolongation of the PR interval until a dropped beat occurs.
– Type 2 (Mobitz II): PR interval is constant, but the P wave is often not followed by a QRS complex.
– Third degree (complete) AV block: no association between the P waves and QRS complexes.

Features of complete heart block: syncope, heart failure, regular bradycardia (30-50 bpm), wide pulse pressure, JVP (jugular venous pressure) cannon waves in neck, variable intensity of S1.

2. Bundle Branch Blocks:
– Electrical conduction travels from the bundle of His to the left and right bundle branches.
– Diagnosed when the duration of the QRS complex on the ECG exceeds 120 ms.

– Right bundle branch block (RBBB).
– Left bundle branch block (LBBB).
– Left anterior fascicular block (LAFB).
– Left posterior fascicular block (LPFB).
– Bifascicular block.
– Trifascicular block.

ECG features of bundle branch blocks:
– RBBB: QRS duration > 120 ms, RSR’ pattern in V1-3 (M-shaped QRS complex), wide S wave in lateral leads (I, aVL, V5-6).
– LBBB: QRS duration > 120 ms, dominant S wave in V1, broad, notched (‘M’-shaped) R wave in V6, broad monophasic R wave in lateral leads (I, aVL, V5-6), absence of Q waves in lateral leads, prolonged R wave peak time > 60 ms in leads V5-6.

WiLLiaM MaRROW is a useful mnemonic for remembering the morphology of the QRS in leads V1 and V6 for LBBB.

This woman is displaying symptoms and signs that are consistent with a diagnosis of meningococcal septicaemia. In the United Kingdom, the majority of cases of meningococcal septicaemia are caused by Neisseria meningitidis group B.

In the prehospital setting, the most suitable medication and method of administration is intramuscular benzylpenicillin 1.2 g. This medication is commonly carried by most General Practitioners and is easier to administer than an intravenous drug in these circumstances.

For close household contacts, prophylaxis can be provided in the form of oral rifampicin 600 mg twice daily for two days.

Acute epiglottitis is inflammation of the epiglottis, which can be life-threatening if not treated promptly. When the soft tissues surrounding the epiglottis are also affected, it is called acute supraglottitis. This condition is most commonly seen in children between the ages of 3 and 5, but it can occur at any age, with adults typically presenting in their 40s and 50s.

In the past, Haemophilus influenzae type B was the main cause of acute epiglottitis, but with the introduction of the Hib vaccination, it has become rare in children. Streptococcus spp. is now the most common causative organism. Other potential culprits include Staphylococcus aureus, Pseudomonas spp., Moraxella catarrhalis, Mycobacterium tuberculosis, and the herpes simplex virus. In immunocompromised patients, Candida spp. and Aspergillus spp. infections can occur.

The typical symptoms of acute epiglottitis include fever, sore throat, painful swallowing, difficulty swallowing secretions (especially in children who may drool), muffled voice, stridor, respiratory distress, rapid heartbeat, tenderness in the front of the neck over the hyoid bone, ear pain, and swollen lymph nodes in the neck. Some patients may also exhibit the tripod sign, where they lean forward on outstretched arms to relieve upper airway obstruction.

To diagnose acute epiglottitis, fibre-optic laryngoscopy is considered the gold standard investigation. However, this procedure should only be performed by an anaesthetist in a setting prepared for intubation or tracheostomy in case of airway obstruction. Other useful tests include a lateral neck X-ray to look for the thumbprint sign, throat swabs, blood cultures, and a CT scan of the neck if an abscess is suspected.

When dealing with a case of acute epiglottitis, it is crucial not to panic or distress the patient, especially in pediatric cases. Avoid attempting to examine the throat with a tongue depressor, as this can trigger spasm and worsen airway obstruction. Instead, keep the patient as calm as possible and immediately call a senior anaesthetist, a senior paediatrician, and an ENT surgeon. Nebulized adrenaline can be used as a temporary measure if there is critical airway obstruction.

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.

Salicylate poisoning initially leads to respiratory alkalosis, followed by metabolic acidosis. Salicylates, like aspirin, stimulate the respiratory center in the medulla, causing hyperventilation and respiratory alkalosis. This is usually the first acid-base imbalance observed in salicylate poisoning. As aspirin is metabolized, it disrupts oxidative phosphorylation in the mitochondria, leading to an increase in lactate levels due to anaerobic metabolism. The accumulation of lactic acid and acidic metabolites then causes metabolic acidosis.

Further Reading:

Salicylate poisoning, particularly from aspirin overdose, is a common cause of poisoning in the UK. One important concept to understand is that salicylate overdose leads to a combination of respiratory alkalosis and metabolic acidosis. Initially, the overdose stimulates the respiratory center, leading to hyperventilation and respiratory alkalosis. However, as the effects of salicylate on lactic acid production, breakdown into acidic metabolites, and acute renal injury occur, it can result in high anion gap metabolic acidosis.

The clinical features of salicylate poisoning include hyperventilation, tinnitus, lethargy, sweating, pyrexia (fever), nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.

When investigating salicylate poisoning, it is important to measure salicylate levels in the blood. The sample should be taken at least 2 hours after ingestion for symptomatic patients or 4 hours for asymptomatic patients. The measurement should be repeated every 2-3 hours until the levels start to decrease. Other investigations include arterial blood gas analysis, electrolyte levels (U&Es), complete blood count (FBC), coagulation studies (raised INR/PTR), urinary pH, and blood glucose levels.

To manage salicylate poisoning, an ABC approach should be followed to ensure a patent airway and adequate ventilation. Activated charcoal can be administered if the patient presents within 1 hour of ingestion. Oral or intravenous fluids should be given to optimize intravascular volume. Hypokalemia and hypoglycemia should be corrected. Urinary alkalinization with intravenous sodium bicarbonate can enhance the elimination of aspirin in the urine. In severe cases, hemodialysis may be necessary.

Urinary alkalinization involves targeting a urinary pH of 7.5-8.5 and checking it hourly. It is important to monitor for hypokalemia as alkalinization can cause potassium to shift from plasma into cells. Potassium levels should be checked every 1-2 hours.

In cases where the salicylate concentration is high (above 500 mg/L in adults or 350 mg/L in children), sodium bicarbonate can be administered intravenously. Hemodialysis is the treatment of choice for severe poisoning and may be indicated in cases of high salicylate levels, resistant metabolic acidosis, acute kidney injury, pulmonary edema, seizures and coma.

This patient is displaying symptoms and signs that are consistent with a diagnosis of phaeochromocytoma. Phaeochromocytoma is a rare functional tumor that originates from chromaffin cells in the adrenal medulla. There are also less common tumors called extra-adrenal paragangliomas, which develop in the ganglia of the sympathetic nervous system. Both types of tumors secrete catecholamines, leading to symptoms and signs associated with hyperactivity of the sympathetic nervous system.

The most common initial symptom is hypertension, which can be either sustained or paroxysmal. Other symptoms tend to be intermittent and can occur frequently or infrequently. As the disease progresses, these symptoms usually become more severe and frequent.

In addition to hypertension, patients with phaeochromocytoma may experience the following clinical features: headache, profuse sweating, palpitations or rapid heartbeat, tremors, fever, nausea and vomiting, anxiety and panic attacks, a sense of impending doom, epigastric or flank pain, constipation, hypertensive retinopathy, postural hypotension due to volume contraction, cardiomyopathy, and café au lait spots.

To confirm a suspected diagnosis of phaeochromocytoma, elevated levels of metanephrines (catecholamine metabolites) can be measured in the blood or urine. This can be done through methods such as a 24-hour urine collection for free catecholamines, vanillylmandelic acid (VMA), and metanephrines, high-performance liquid chromatography for catecholamines in plasma and/or urine, or radioimmunoassay (RIA) for urinary/plasma metanephrines.

Once the diagnosis of phaeochromocytoma is biochemically confirmed, imaging methods can be used to locate the tumor. The first imaging modality to be used is a CT scan, which has an overall sensitivity of 89%. An MRI scan is the most sensitive modality for identifying the tumor, especially in cases of extra-adrenal tumors or metastatic disease, with an overall sensitivity of 98%. In cases where CT or MRI does not show a tumor, a nuclear medicine scan such as MIBG scintigraphy can be useful.

Phenoxymethylpenicillin is the preferred antibiotic for treating streptococcal sore throat, especially in patients with a CENTOR score of 3/4 and a FeverPAIN score of 4/5. In such cases, antibiotics are necessary to effectively treat the infection.

Further Reading:

Pharyngitis and tonsillitis are common conditions that cause inflammation in the throat. Pharyngitis refers to inflammation of the oropharynx, which is located behind the soft palate, while tonsillitis refers to inflammation of the tonsils. These conditions can be caused by a variety of pathogens, including viruses and bacteria. The most common viral causes include rhinovirus, coronavirus, parainfluenza virus, influenza types A and B, adenovirus, herpes simplex virus type 1, and Epstein Barr virus. The most common bacterial cause is Streptococcus pyogenes, also known as Group A beta-hemolytic streptococcus (GABHS). Other bacterial causes include Group C and G beta-hemolytic streptococci and Fusobacterium necrophorum.

Group A beta-hemolytic streptococcus is the most concerning pathogen as it can lead to serious complications such as rheumatic fever and glomerulonephritis. These complications can occur due to an autoimmune reaction triggered by antigen/antibody complex formation or from cell damage caused by bacterial exotoxins.

When assessing a patient with a sore throat, the clinician should inquire about the duration and severity of the illness, as well as associated symptoms such as fever, malaise, headache, and joint pain. It is important to identify any red flags and determine if the patient is immunocompromised. Previous non-suppurative complications of Group A beta-hemolytic streptococcus infection should also be considered, as there is an increased risk of further complications with subsequent infections.

Red flags that may indicate a more serious condition include severe pain, neck stiffness, or difficulty swallowing. These symptoms may suggest epiglottitis or a retropharyngeal abscess, which require immediate attention.

To determine the likelihood of a streptococcal infection and the need for antibiotic treatment, two scoring systems can be used: CENTOR and FeverPAIN. The CENTOR criteria include tonsillar exudate, tender anterior cervical lymphadenopathy or lymphadenitis, history of fever, and absence of cough. The FeverPAIN criteria include fever, purulence, rapid onset of symptoms, severely inflamed tonsils, and absence of cough or coryza. Based on the scores from these criteria, the likelihood of a streptococcal infection can be estimated, and appropriate management can be undertaken.

The percentage of patients who survive to hospital discharge after experiencing an out of hospital cardiac arrest.

Further Reading:

Cardiopulmonary arrest is a serious event with low survival rates. In non-traumatic cardiac arrest, only about 20% of patients who arrest as an in-patient survive to hospital discharge, while the survival rate for out-of-hospital cardiac arrest is approximately 8%. The Resus Council BLS/AED Algorithm for 2015 recommends chest compressions at a rate of 100-120 per minute with a compression depth of 5-6 cm. The ratio of chest compressions to rescue breaths is 30:2.

After a cardiac arrest, the goal of patient care is to minimize the impact of post cardiac arrest syndrome, which includes brain injury, myocardial dysfunction, the ischaemic/reperfusion response, and the underlying pathology that caused the arrest. The ABCDE approach is used for clinical assessment and general management. Intubation may be necessary if the airway cannot be maintained by simple measures or if it is immediately threatened. Controlled ventilation is aimed at maintaining oxygen saturation levels between 94-98% and normocarbia. Fluid status may be difficult to judge, but a target mean arterial pressure (MAP) between 65 and 100 mmHg is recommended. Inotropes may be administered to maintain blood pressure. Sedation should be adequate to gain control of ventilation, and short-acting sedating agents like propofol are preferred. Blood glucose levels should be maintained below 8 mmol/l. Pyrexia should be avoided, and there is some evidence for controlled mild hypothermia but no consensus on this.

Post ROSC investigations may include a chest X-ray, ECG monitoring, serial potassium and lactate measurements, and other imaging modalities like ultrasonography, echocardiography, CTPA, and CT head, depending on availability and skills in the local department. Treatment should be directed towards the underlying cause, and PCI or thrombolysis may be considered for acute coronary syndrome or suspected pulmonary embolism, respectively.

Patients who are comatose after ROSC without significant pre-arrest comorbidities should be transferred to the ICU for supportive care. Neurological outcome at 72 hours is the best prognostic indicator of outcome.

Lidocaine is a tertiary amine that is primarily utilized as a local anesthetic. It can also be employed in the treatment of ventricular arrhythmias. The mechanism of action of lidocaine as a local anesthetic involves its diffusion in the form of an uncharged base through neural sheaths and the axonal membrane. It then reaches the internal surface of the cell membrane sodium channels, where it exerts its effect by blocking the fast voltage-gated sodium channels. This alteration in signal conduction prevents the depolarization of the postsynaptic neuron’s membrane, thereby inhibiting the transmission of pain signals.

In a plain 1% lidocaine solution, each 1 ml contains 10 mg of lidocaine hydrochloride. The maximum safe dose of plain lidocaine is 3 mg/kg, with a maximum limit of 200 mg. However, when administered with adrenaline in a 1:200,000 ratio, the maximum safe dose increases to 7 mg/kg, with a maximum limit of 500 mg. It is important to note that the combination of lidocaine and adrenaline should not be used in extremities such as fingers, toes, and the nose due to the risk of vasoconstriction and tissue necrosis.

The half-life of lidocaine ranges from 1.5 to 2 hours. It exhibits a rapid onset of action within a few minutes and has a duration of action of 30 to 60 minutes when used alone. However, when co-administered with adrenaline, its duration of action is prolonged. It is worth mentioning that lidocaine tends to induce vasodilation, primarily attributed to the inhibition of action potentials in vasoconstrictor sympathetic nerves through the blocking of sodium channels.

Hepatitis B vaccination is included in the routine childhood immunisation schedule to provide long-term protection against hepatitis for children under 1 year of age. For these children, the vaccination consists of a primary course that includes the diphtheria with tetanus, pertussis, hepatitis B, poliomyelitis, and Haemophilus influenza type B vaccine. This primary course is given at 4 weekly intervals.

The Hepatitis B vaccine is a conjugate vaccine that contains a surface antigen of the hepatitis virus (HBsAg) and is combined with an aluminium adjuvant to enhance its effectiveness. It is produced using a recombinant DNA technique.

When administering the vaccine to adults and older children, the preferred injection site is the deltoid muscle. However, in younger children, the anterolateral thigh is the preferred site. It is not recommended to inject the vaccine in the gluteal area as it has been found to have reduced efficacy.

The standard vaccination regime for Hepatitis B consists of three primary doses. The initial dose is followed by further doses at one and six months later. A booster dose is recommended at five years if the individual is still at risk.

In cases of post-exposure prophylaxis, an accelerated vaccination regime is used. This involves administering a vaccination at the time of exposure, followed by repeat doses at one and two months later.

In high-risk situations, Hepatitis B immunoglobulin can be given up to 7 days after exposure. Ideally, it should be administered within 12 hours, but according to the BNF, it can still be effective if given within 7 days after exposure.

Zygomaticomaxillary complex fractures, also known as quadramalar or tripod fractures, make up around 40% of all midface fractures and are the second most common facial bone fractures after nasal bone fractures.

These injuries typically occur when a direct blow is delivered to the malar eminence of the cheek. They consist of four components:

1. Widening of the zygomaticofrontal suture
2. Fracture of the zygomatic arch
3. Fracture of the inferior orbital rim and the walls of the anterior and posterior maxillary sinuses
4. Fracture of the lateral orbital rim.