Respiratory alkalosis can be caused by hyperventilation, such as during periods of anxiety. It can also be a result of conditions like pulmonary embolism, CNS disorders (such as stroke or encephalitis), altitude, pregnancy, or the early stages of aspirin overdose.

Respiratory acidosis is often associated with chronic obstructive pulmonary disease (COPD) or life-threatening asthma. Other causes include pulmonary edema, sedative drug overdose (such as opiates or benzodiazepines), neuromuscular disease, obesity, or certain medications.

Metabolic alkalosis can occur due to vomiting, potassium depletion (often caused by diuretic usage), Cushing’s syndrome, or Conn’s syndrome.

Metabolic acidosis with a raised anion gap can be caused by conditions like lactic acidosis (which can result from hypoxemia, shock, sepsis, or infarction) or ketoacidosis (commonly seen in diabetes, starvation, or alcohol excess). Other causes include renal failure or poisoning (such as late stages of aspirin overdose, methanol, or ethylene glycol).

Metabolic acidosis with a normal anion gap can be attributed to conditions like renal tubular acidosis, diarrhea, ammonium chloride ingestion, or adrenal insufficiency.

The majority of dissections happen in individuals between the ages of 40 and 70, with the highest occurrence observed in the age group of 50 to 65.

Further Reading:

Aortic dissection is a life-threatening condition in which blood flows through a tear in the innermost layer of the aorta, creating a false lumen. Prompt treatment is necessary as the mortality rate increases by 1-2% per hour. There are different classifications of aortic dissection, with the majority of cases being proximal. Risk factors for aortic dissection include hypertension, atherosclerosis, connective tissue disorders, family history, and certain medical procedures.

The presentation of aortic dissection typically includes sudden onset sharp chest pain, often described as tearing or ripping. Back pain and abdominal pain are also common, and the pain may radiate to the neck and arms. The clinical picture can vary depending on which aortic branches are affected, and complications such as organ ischemia, limb ischemia, stroke, myocardial infarction, and cardiac tamponade may occur. Common signs and symptoms include a blood pressure differential between limbs, pulse deficit, and a diastolic murmur.

Various investigations can be done to diagnose aortic dissection, including ECG, CXR, and CT with arterial contrast enhancement (CTA). CT is the investigation of choice due to its accuracy in diagnosis and classification. Other imaging techniques such as transoesophageal echocardiography (TOE), magnetic resonance imaging/angiography (MRI/MRA), and digital subtraction angiography (DSA) are less commonly used.

Management of aortic dissection involves pain relief, resuscitation measures, blood pressure control, and referral to a vascular or cardiothoracic team. Opioid analgesia should be given for pain relief, and resuscitation measures such as high flow oxygen and large bore IV access should be performed. Blood pressure control is crucial, and medications such as labetalol may be used to reduce systolic blood pressure. Hypotension carries a poor prognosis and may require careful fluid resuscitation. Treatment options depend on the type of dissection, with type A dissections typically requiring urgent surgery and type B dissections managed by thoracic endovascular aortic repair (TEVAR) and blood pressure control optimization.

The current recommendations from NICE for managing warfarin in the presence of bleeding or an abnormal INR are as follows:

In cases of major active bleeding, regardless of the INR level, the first step is to stop administering warfarin. Next, 5 mg of vitamin K (phytomenadione) should be given intravenously. Additionally, dried prothrombin complex concentrate, which contains factors II, VII, IX, and X, should be administered. If dried prothrombin complex is not available, fresh frozen plasma can be given at a dose of 15 ml/kg.

If the INR is greater than 8.0 and there is minor bleeding, warfarin should be stopped. Slow injection of 1-3 mg of vitamin K can be given, and this dose can be repeated after 24 hours if the INR remains high. Warfarin can be restarted once the INR is less than 5.0.

If the INR is greater than 8.0 with no bleeding, warfarin should be stopped. Oral administration of 1-5 mg of vitamin K can be given, and this dose can be repeated after 24 hours if the INR remains high. Warfarin can be restarted once the INR is less than 5.0.

If the INR is between 5.0-8.0 with minor bleeding, warfarin should be stopped. Slow injection of 1-3 mg of vitamin K can be given, and warfarin can be restarted once the INR is less than 5.0.

If the INR is between 5.0-8.0 with no bleeding, one or two doses of warfarin should be withheld, and the subsequent maintenance dose should be reduced.

For more information, please refer to the NICE Clinical Knowledge Summary on the management of warfarin therapy and the BNF guidance on the use of phytomenadione.

This child is displaying a typical pattern of symptoms for type I diabetes mellitus. He has recently experienced increased urination, excessive thirst, weight loss, and fatigue. Blood tests have revealed metabolic acidosis, and the presence of ketones in his urine indicates the development of diabetic ketoacidosis.

In this scenario, a 35-year-old female presents to the emergency department with complaints of abdominal cramps and bloating. She mentions that she has not had a bowel movement for 2 days. After conducting blood tests, which all come back normal, and assessing her vital signs, which are also normal, it is suspected that she may have constipation predominant irritable bowel syndrome. This suspicion is based on her history of recurrent abdominal pain and bloating over the past 6-9 months, for which she has already consulted her primary care physician.

To address the constipation symptoms, a laxative is considered as a potential treatment option. However, it is important to exercise caution when prescribing medications for patients with irritable bowel syndrome. One medication that should be avoided in these patients is lactulose.

Further Reading:

Irritable bowel syndrome (IBS) is a chronic disorder that affects the interaction between the gut and the brain. The exact cause of IBS is not fully understood, but factors such as genetics, drug use, enteric infections, diet, and psychosocial factors are believed to play a role. The main symptoms of IBS include abdominal pain, changes in stool form and/or frequency, and bloating. IBS can be classified into subtypes based on the predominant stool type, including diarrhea-predominant, constipation-predominant, mixed, and unclassified.

Diagnosing IBS involves using the Rome IV criteria, which includes recurrent abdominal pain associated with changes in stool frequency and form. It is important to rule out other more serious conditions that may mimic IBS through a thorough history, physical examination, and appropriate investigations. Treatment for IBS primarily involves diet and lifestyle modifications. Patients are advised to eat regular meals with a healthy, balanced diet and adjust their fiber intake based on symptoms. A low FODMAP diet may be trialed, and a dietician may be consulted for guidance. Regular physical activity and weight management are also recommended.

Psychosocial factors, such as stress, anxiety, and depression, should be addressed and managed appropriately. If constipation is a predominant symptom, soluble fiber supplements or foods high in soluble fiber may be recommended. Laxatives can be considered if constipation persists, and linaclotide may be tried if optimal doses of previous laxatives have not been effective. Antimotility drugs like loperamide can be used for diarrhea, and antispasmodic drugs or low-dose tricyclic antidepressants may be prescribed for abdominal pain. If symptoms persist or are refractory to treatment, alternative diagnoses should be considered, and referral to a specialist may be necessary.

Overall, the management of IBS should be individualized based on the patient’s symptoms and psychosocial situation. Clear explanation of the condition and providing resources for patient education, such as the NHS patient information leaflet and support from organizations like The IBS Network, can also be beneficial.

Acute pancreatitis is a common and serious cause of acute abdominal pain. It occurs when the pancreas becomes inflamed, leading to the release of enzymes that cause self-digestion of the organ.

The most common causes of acute pancreatitis are gallstones and alcohol consumption. Many cases are also of unknown origin. To remember the various causes, the mnemonic ‘I GET SMASHED’ can be helpful:

– I: Idiopathic
– G: Gallstones
– E: Ethanol
– T: Trauma
– S: Steroids
– M: Mumps
– A: Autoimmune
– S: Scorpion stings
– H: Hyperlipidemia/hypercalcemia
– E: ERCP
– D: Drugs

The clinical features of acute pancreatitis include severe epigastric pain, nausea and vomiting, referral of pain to specific dermatomes (or shoulder tip via the phrenic nerve), fever/sepsis, epigastric tenderness, jaundice, and signs such as Gray-Turner sign (ecchymosis of the flank) and Cullen sign (ecchymosis of the peri-umbilical area).

The stimulation of the thoracic splanchnic nerves is responsible for the referred pain to the T6-10 dermatomes that is sometimes observed in pancreatitis and other pancreatic disorders.

When investigating acute pancreatitis in the emergency department, it is important to perform blood glucose testing, a full blood count (which often shows an elevated white cell count), urea and electrolyte testing, calcium testing, liver function tests, coagulation screening, serum amylase testing (which should be more than 5 times the normal limit), an ECG, arterial blood gas analysis, and an abdominal X-ray.

Treatment for acute pancreatitis involves providing the patient with oxygen, adequate pain relief (including antiemetics), and fluid resuscitation. A nasogastric tube and urinary catheter should be inserted, and fluid balance should be carefully monitored. Most patients require management in a high dependency unit (HDU) or intensive care unit (ICU) setting.

Acute pancreatitis has a significant mortality rate, and complications are common. Early complications may include severe sepsis and circulatory shock, acute renal failure, disseminated intravascular coagulation, hypocalcemia, acute respiratory distress syndrome and pancreatic encephalopathy.

Anterior uveitis refers to the inflammation of the iris and is characterized by a painful and red eye. It is often accompanied by symptoms such as sensitivity to light, excessive tearing, and a decrease in visual clarity. In less than 10% of cases, the inflammation may extend to the posterior chamber. The condition can also lead to the formation of adhesions between the iris and the lens or cornea, resulting in an irregularly shaped pupil known as synechia. In severe cases, pus may accumulate in the front part of the eye, specifically the anterior chamber, causing a condition called hypopyon.

There are various factors that can cause anterior uveitis, including idiopathic cases where no specific cause can be identified. Other causes include trauma, chronic joint diseases like spondyloarthropathies and juvenile chronic arthritis, ankylosing spondylitis, inflammatory bowel disease, psoriasis, sarcoidosis, and infections such as Lyme disease, tuberculosis, leptospirosis, herpes simplex virus (HSV), and varicella-zoster virus (VZV). It is worth noting that approximately 50% of patients with anterior uveitis have a strong association with the HLA-B27 genotype.

Complications that can arise from uveitis include the development of cataracts, glaucoma, band keratopathy (a condition where calcium deposits form on the cornea), and even blindness.

Cephalexin is a type of cephalosporin medication that is eliminated from the body through the kidneys. Cephalosporin drugs have been linked to direct harm to the kidneys and can build up in individuals with kidney problems.

The typical dosage for cephalexin is 250 mg taken four times a day. For more severe infections or infections caused by organisms that are less susceptible to the medication, the dosage may be doubled. The manufacturer recommends reducing the frequency of dosing in individuals with kidney impairment. In cases where the glomerular filtration rate (GFR) is less than 10 ml/minute, the recommended dosage is 250-500 mg taken once or twice a day, depending on the severity of the infection.

Lithium is a medication used to stabilize mood and is approved for the treatment and prevention of mania, bipolar disorder, recurrent depression, and aggressive or self-harming behavior. During pregnancy and the postnatal period, it is important to monitor lithium levels more frequently. If taken during the first trimester, lithium is associated with an increased risk of fetal cardiac malformations, such as Ebstein’s anomaly. If taken during the second and third trimesters, there is a risk of various complications in the newborn, including hypotonia, lethargy, feeding problems, hypothyroidism, goiter, and nephrogenic diabetes insipidus.

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

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

Drug: Aminoglycosides (e.g. gentamicin)
Adverse effects: Aminoglycosides can cause ototoxicity and deafness in the fetus.

Drug: Aspirin
Adverse effects: High doses of aspirin can lead to first-trimester abortions, delayed onset labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses (e.g. 75 mg) do not pose a significant risk.

Drug: Benzodiazepines (e.g. diazepam)
Adverse effects: When taken late in pregnancy, benzodiazepines can cause respiratory depression and a neonatal withdrawal syndrome.

Drug: Calcium-channel blockers
Adverse effects: If taken during the first trimester, calcium-channel blockers can cause phalangeal abnormalities. If taken during the second and third trimesters, they can lead to fetal growth retardation.

The BTS guidelines for acute asthma in children recommend administering oral steroids early in the treatment of asthma attacks. It is advised to give a dose of 20 mg prednisolone for children aged 2–5 years and a dose of 30–40 mg for children over 5 years old. If a child is already taking maintenance steroid tablets, they should receive 2 mg/kg prednisolone, up to a maximum dose of 60 mg. If a child vomits after taking the medication, the dose of prednisolone should be repeated. In cases where a child is unable to keep down orally ingested medication, intravenous steroids should be considered. Typically, treatment for up to three days is sufficient, but the duration of the course should be adjusted based on the time needed for recovery. Tapering off the medication is not necessary unless the steroid course exceeds 14 days. For more information, refer to the BTS/SIGN Guideline on the Management of Asthma.

The most probable diagnosis in this situation is Goodpasture’s syndrome, a rare autoimmune vasculitic disorder characterized by three main symptoms: pulmonary hemorrhage, glomerulonephritis, and the presence of anti-glomerular basement membrane (Anti-GBM) antibodies. Goodpasture’s syndrome is more prevalent in men, particularly in smokers. It is also associated with HLA-B7 and HLA-DRw2.

The clinical manifestations of Goodpasture’s syndrome include constitutional symptoms like fever, fatigue, nausea, and weight loss. Patients may also experience hemoptysis or pulmonary hemorrhage, chest pain, breathlessness, and inspiratory crackles at the lung bases. Anemia due to bleeding within the lungs, arthralgia, rapidly progressive glomerulonephritis, hematuria, hypertension, and rarely hepatosplenomegaly may also be present.

Blood tests will reveal iron deficiency anemia, an elevated white cell count, and renal impairment. Elisa for Anti-GBM antibodies is highly sensitive and specific, but it is not widely available. Approximately 30% of patients may also have circulating antineutrophilic cytoplasmic antibodies (ANCAs), although these are not specific for Goodpasture’s syndrome and can be found in other conditions such as Wegener’s granulomatosis, which also cause renal impairment and pulmonary hemorrhage.

Diagnosis is typically confirmed through a renal biopsy, which can detect the presence of anti-GBM antibodies. This would be the most appropriate investigation to confirm the diagnosis in this case.

The management of Goodpasture’s syndrome involves a combination of plasmapheresis to remove circulating antibodies and the use of corticosteroids or cyclophosphamide.

Etomidate is not recommended for use in septic patients because it can suppress adrenal cortisol production, leading to increased morbidity and mortality in sepsis cases. However, it is a suitable choice for haemodynamically unstable patients who are not experiencing sepsis, as it does not cause significant hypotension like other induction agents. Additionally, etomidate can be beneficial for patients with head injuries and elevated intracranial pressure, as it reduces cerebral blood flow and intracranial pressure.

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 Alcohol Use Disorder Identification Test (AUDIT) has been developed by the World Health Organization as a straightforward screening tool to detect early signs of hazardous and harmful drinking, as well as mild dependence. This assessment is more comprehensive than the CAGE questionnaire and is currently recommended by NICE for identifying alcohol misuse.

NICE, the National Institute for Health and Care Excellence, suggests the use of specific assessment tools to evaluate the nature and severity of alcohol misuse. These tools include AUDIT for identification and as a routine outcome measure, SADQ or LDQ for assessing the severity of dependence, CIWA-Ar for evaluating the severity of withdrawal symptoms, and APQ for understanding the nature and extent of problems resulting from alcohol misuse.

For more information on this topic, you can refer to the NICE guidance titled Alcohol-use disorders: diagnosis, assessment and management of harmful drinking and alcohol dependence.

If an adult with a head injury experiences more than one episode of vomiting, it is recommended to undergo a CT scan of the head. There are several criteria for an urgent CT scan in individuals with a head injury, including a Glasgow Coma Scale (GCS) score of less than 13 on initial assessment in the emergency department (ED), a GCS score of less than 15 at 2 hours after the injury on assessment in the ED, suspected open or depressed skull fracture, any sign of basal skull fracture (such as haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, or Battle’s sign), post-traumatic seizure, new focal neurological deficit, and being on anticoagulation medication. If any of these signs are present, a CT scan should be performed within 1 hour, except for patients on anticoagulation medication who should undergo a CT scan within 8 hours if none of the other signs are present. However, if a patient on anticoagulation medication has any of the other signs, the CT scan should be performed within 1 hour.

Further Reading:

Indications for CT Scanning in Head Injuries (Adults):
– CT head scan should be performed within 1 hour if any of the following features are present:
– GCS < 13 on initial assessment in the ED
– GCS < 15 at 2 hours after the injury on assessment in the ED
– Suspected open or depressed skull fracture
– Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign)
– Post-traumatic seizure
– New focal neurological deficit
– > 1 episode of vomiting

Indications for CT Scanning in Head Injuries (Children):
– CT head scan should be performed within 1 hour if any of the features in List 1 are present:
– Suspicion of non-accidental injury
– Post-traumatic seizure but no history of epilepsy
– GCS < 14 on initial assessment in the ED for children more than 1 year of age
– Paediatric GCS < 15 on initial assessment in the ED for children under 1 year of age
– At 2 hours after the injury, GCS < 15
– Suspected open or depressed skull fracture or tense fontanelle
– Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign)
– New focal neurological deficit
– For children under 1 year, presence of bruise, swelling or laceration of more than 5 cm on the head

– CT head scan should be performed within 1 hour if none of the above features are present but two or more of the features in List 2 are present:
– Loss of consciousness lasting more than 5 minutes (witnessed)
– Abnormal drowsiness
– Three or more discrete episodes of vomiting
– Dangerous mechanism of injury (high-speed road traffic accident, fall from a height.

Cement contains lime, which is a powerful alkali, and this can cause a serious eye emergency that requires immediate treatment. Alkaline chemicals, such as oven cleaner, ammonia, household bleach, drain cleaner, oven cleaner, and plaster, can also cause damage to the eyes. They lead to colliquative necrosis, which is a type of tissue death that results in liquefaction. On the other hand, acids cause damage through coagulative necrosis. Common acids that can harm the eyes include toilet cleaners, certain household cleaning products, and battery fluid.

The initial management of a patient with cement or alkali exposure to the eyes should be as follows:

1. Irrigate the eye with a large amount of normal saline for 20-30 minutes.
2. Administer local anaesthetic drops every 5 minutes to help keep the eye open and alleviate pain.
3. Monitor the pH every 5 minutes until a neutral pH (7.0-7.5) is achieved. Briefly pause irrigation to test the fluid from the forniceal space using litmus paper.

After the initial management, a thorough examination should be conducted, which includes the following steps:

1. Examine the eye directly and with a slit lamp.
2. Remove any remaining cement debris from the surface of the eye.
3. Evert the eyelids to check for hidden cement debris.
4. Administer fluorescein drops and check for corneal abrasion.
5. Assess visual acuity, which may be reduced.
6. Perform fundoscopy to check for retinal necrosis if the alkali has penetrated the sclera.
7. Measure intraocular pressure through tonometry to detect secondary glaucoma.

Once the eye’s pH has returned to normal, irrigation can be stopped, and the patient should be promptly referred to an ophthalmology specialist for further evaluation.

Potential long-term complications of cement or alkali exposure to the eyes include closed-angle glaucoma, cataract formation, entropion, keratitis sicca, and permanent vision loss.

St. John’s wort can reduce the effectiveness of warfarin, an anticoagulant medication. Therefore, it is important for patients who are taking warfarin to be aware that they should avoid using St. John’s wort as a supplement. For more information on this interaction, you can refer to the BNF section on warfarin interactions.

When patients with diabetic ketoacidosis (DKA) are treated with insulin infusion, it is expected that their plasma bicarbonate levels will increase by at least 3 mmol/L per hour. Insulin therapy is aimed at correcting both hyperglycemia and ketoacidosis. However, if capillary ketones are not decreasing by at least 0.5 mmol/L per hour, venous bicarbonate is not rising by at least 3 mmol/L per hour, or plasma glucose is not decreasing by at least 3 mmol/L per hour, the insulin infusion rate should be reevaluated.

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.

Anaphylaxis is a severe and life-threatening hypersensitivity reaction that can have sudden onset and progression. It is characterized by skin or mucosal changes and can lead to life-threatening airway, breathing, or circulatory problems. Anaphylaxis can be allergic or non-allergic in nature.

In allergic anaphylaxis, there is an immediate hypersensitivity reaction where an antigen stimulates the production of IgE antibodies. These antibodies bind to mast cells and basophils. Upon re-exposure to the antigen, the IgE-covered cells release histamine and other inflammatory mediators, causing smooth muscle contraction and vasodilation.

Non-allergic anaphylaxis occurs when mast cells degrade due to a non-immune mediator. The clinical outcome is the same as in allergic anaphylaxis.

The management of anaphylaxis is the same regardless of the cause. Adrenaline is the most important drug and should be administered as soon as possible. The recommended doses for adrenaline vary based on age. Other treatments include high flow oxygen and an IV fluid challenge. Corticosteroids and chlorpheniramine are no longer recommended, while non-sedating antihistamines may be considered as third-line treatment after initial stabilization of airway, breathing, and circulation.

Common causes of anaphylaxis include food (such as nuts, which is the most common cause in children), drugs, and venom (such as wasp stings). Sometimes it can be challenging to determine if a patient had a true episode of anaphylaxis. In such cases, serum tryptase levels may be measured, as they remain elevated for up to 12 hours following an acute episode of anaphylaxis.

The Resuscitation Council (UK) provides guidelines for the management of anaphylaxis, including a visual algorithm that outlines the recommended steps for treatment.
https://www.resus.org.uk/sites/default/files/2021-05/Emergency%20Treatment%20of%20Anaphylaxis%20May%202021_0.pdf

Technetium 99 (Tc-99) pertechnetate scintigraphy is the preferred imaging method for evaluating frostbite. This technique is highly accurate in detecting tissue damage and provides both sensitivity and specificity.

Further Reading:

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, the basal metabolic rate decreases and cell signaling between neurons decreases, leading to reduced tissue perfusion. This can result in decreased myocardial contractility, vasoconstriction, ventilation-perfusion mismatch, and increased blood viscosity. Symptoms of hypothermia progress as the core temperature drops, starting with compensatory increases in heart rate and shivering, and eventually leading to bradyarrhythmias, prolonged PR, QRS, and QT intervals, and cardiac arrest.

In the management of hypothermic cardiac arrest, ALS should be initiated with some modifications. The pulse check during CPR should be prolonged to 1 minute due to difficulty in obtaining a pulse. Rewarming the patient is important, and mechanical ventilation may be necessary due to stiffness of the chest wall. Drug metabolism is slowed in hypothermic patients, so dosing of drugs should be adjusted or withheld. Electrolyte disturbances are common in hypothermic patients and should be corrected.

Frostbite refers to a freezing injury to human tissue and occurs when tissue temperature drops below 0ºC. It can be classified as superficial or deep, with superficial frostbite affecting the skin and subcutaneous tissues, and deep frostbite affecting bones, joints, and tendons. Frostbite can be classified from 1st to 4th degree based on the severity of the injury. Risk factors for frostbite include environmental factors such as cold weather exposure and medical factors such as peripheral vascular disease and diabetes.

Signs and symptoms of frostbite include skin changes, cold sensation or firmness to the affected area, stinging, burning, or numbness, clumsiness of the affected extremity, and excessive sweating, hyperemia, and tissue gangrene. Frostbite is diagnosed clinically and imaging may be used in some cases to assess perfusion or visualize occluded vessels. Management involves moving the patient to a warm environment, removing wet clothing, and rapidly rewarming the affected tissue. Analgesia should be given as reperfusion is painful, and blisters should be de-roofed and aloe vera applied. Compartment syndrome is a risk and should be monitored for. Severe cases may require surgical debridement of amputation.

Lown-Ganong-Levine (LGL) syndrome is a condition that affects the electrical conducting system of the heart. It is classified as a pre-excitation syndrome, similar to the more well-known Wolff-Parkinson-White (WPW) syndrome. However, unlike WPW syndrome, LGL syndrome does not involve an accessory pathway for conduction. Instead, it is believed that there may be accessory fibers present that bypass all or part of the atrioventricular node.

When looking at an electrocardiogram (ECG) of a patient with LGL syndrome in sinus rhythm, there are several characteristic features to observe. The PR interval, which represents the time it takes for the electrical signal to travel from the atria to the ventricles, is typically shortened and measures less than 120 milliseconds. The QRS duration, which represents the time it takes for the ventricles to contract, is normal. The P wave, which represents the electrical activity of the atria, may be normal or inverted. However, what distinguishes LGL syndrome from other pre-excitation syndromes is the absence of a delta wave, which is a slurring of the initial rise in the QRS complex.

It is important to note that LGL syndrome predisposes individuals to paroxysmal supraventricular tachycardia (SVT), a rapid heart rhythm that originates above the ventricles. However, it does not increase the risk of developing atrial fibrillation or flutter, which are other types of abnormal heart rhythms.

Blood transfusion is a crucial medical treatment that can save lives, but it also comes with various risks and potential problems. These include immunological complications, administration errors, infections, and immune dilution. While there have been improvements in safety procedures and a reduction in transfusion usage, errors and adverse reactions still occur.

One serious complication is acute haemolytic transfusion reactions, which happen when incompatible red cells are transfused and react with the patient’s own antibodies. This usually occurs due to human error, such as mislabelling sample tubes or request forms. Symptoms of this reaction include a feeling of impending doom, fever, chills, pain and warmth at the transfusion site, nausea, vomiting, and back, joint, and chest pain. Immediate action should be taken to stop the transfusion, replace the donor blood with normal saline or another suitable crystalloid, and check the blood to confirm the intended recipient. IV diuretics may be administered to increase renal blood flow, and urine output should be maintained.

Another common complication is febrile transfusion reaction, which presents with a 1-degree rise in temperature from baseline, along with chills and malaise. This reaction is usually caused by cytokines from leukocytes in the transfused blood components. Supportive treatment is typically sufficient, and paracetamol can be helpful.

Allergic reactions can also occur, usually due to foreign plasma proteins or anti-IgA. These reactions often present with urticaria, pruritus, and hives, and in severe cases, laryngeal edema or bronchospasm may occur. Symptomatic treatment with antihistamines is usually enough, and there is usually no need to stop the transfusion. However, if anaphylaxis occurs, the transfusion should be stopped, and the patient should be administered adrenaline and treated according to the ALS protocol.

Transfusion-related acute lung injury (TRALI) is a severe complication characterized by non-cardiogenic pulmonary edema within 6 hours of transfusion. It is associated with antibodies in the donor blood reacting with recipient leukocyte antigens. This is the most common cause of death related to transfusion reactions. Treatment involves stopping the transfusion, administering oxygen, and providing aggressive respiratory support in approximately 75% of patients. Diuretic usage should be avoided.

The tracheal opening can be classified using the Cormack-Lehane grading system. This system categorizes the views obtained through direct laryngoscopy based on the structures that are visible. More information about this classification system can be found in the notes provided below.

Further Reading:

A difficult airway refers to a situation where factors have been identified that make airway management more challenging. These factors can include body habitus, head and neck anatomy, mouth characteristics, jaw abnormalities, and neck mobility. The LEMON criteria can be used to predict difficult intubation by assessing these factors. The criteria include looking externally at these factors, evaluating the 3-3-2 rule which assesses the space in the mouth and neck, assessing the Mallampati score which measures the distance between the tongue base and roof of the mouth, and considering any upper airway obstructions or reduced neck mobility.

Direct laryngoscopy is a method used to visualize the larynx and assess the size of the tracheal opening. The Cormack-Lehane grading system can be used to classify the tracheal opening, with higher grades indicating more difficult access. In cases of a failed airway, where intubation attempts are unsuccessful and oxygenation cannot be maintained, the immediate priority is to oxygenate the patient and prevent hypoxic brain injury. This can be done through various measures such as using a bag-valve-mask ventilation, high flow oxygen, suctioning, and optimizing head positioning.

If oxygenation cannot be maintained, it is important to call for help from senior medical professionals and obtain a difficult airway trolley if not already available. If basic airway management techniques do not improve oxygenation, further intubation attempts may be considered using different equipment or techniques. If oxygen saturations remain below 90%, a surgical airway such as a cricothyroidotomy may be necessary.

Post-intubation hypoxia can occur for various reasons, and the mnemonic DOPES can be used to identify and address potential problems. DOPES stands for displacement of the endotracheal tube, obstruction, pneumothorax, equipment failure, and stacked breaths. If intubation attempts fail, a maximum of three attempts should be made before moving to an alternative plan, such as using a laryngeal mask airway or considering a cricothyroidotomy.

For the treatment of pregnant women with lower urinary tract infections (UTIs), it is recommended to provide them with an immediate prescription for antibiotics. It is important to consider their previous urine culture and susceptibility results, as well as any prior use of antibiotics that may have contributed to the development of resistant bacteria. Before starting antibiotics, it is advised to obtain a midstream urine sample from pregnant women and send it for culture and susceptibility testing.

Once the microbiological results are available, it is necessary to review the choice of antibiotic. If the bacteria are found to be resistant, it is recommended to switch to a narrow-spectrum antibiotic whenever possible. The choice of antibiotics for pregnant women aged 12 years and over is summarized below:

First-choice:
– Nitrofurantoin 100 mg modified-release taken orally twice daily for 3 days, if the estimated glomerular filtration rate (eGFR) is above 45 ml/minute.

Second-choice (if there is no improvement in lower UTI symptoms with the first-choice antibiotic for at least 48 hours, or if the first-choice is not suitable):
– Amoxicillin 500 mg taken orally three times daily for 7 days (only if culture results are available and show susceptibility).
– Cefalexin 500 mg taken twice daily for 7 days.

For alternative second-choice antibiotics, it is recommended to consult a local microbiologist and choose the appropriate antibiotics based on the culture and sensitivity results.

Functional abdominal pain is a common issue among children in this age group. The pain can occur in episodes or be continuous. In order to diagnose functional abdominal pain, it is important to rule out any inflammatory, anatomical, metabolic, or neoplastic causes that could explain the symptoms. The criteria for diagnosis must be met at least once a week for a minimum of two months.

If the pain is present for at least 25% of the time and there is a loss of daily functioning, it is referred to as functional abdominal pain syndrome. In this syndrome, additional somatic symptoms such as headache, limb pain, or sleep disturbance are often present.

For a diagnosis of irritable bowel syndrome, the pain must also improve with defecation or be associated with changes in the frequency and form of stools.

School refusal is typically not associated with pain outside of school time. Since this child is experiencing pain on weekends, it makes the diagnosis of school refusal less likely.

Abdominal migraine is characterized by intense, acute periumbilical pain that occurs in paroxysmal episodes lasting over an hour. Patients generally have periods of wellness lasting weeks to months between attacks. The pain is often accompanied by anorexia, nausea, vomiting, headache, photophobia, and pallor.

Based on the child’s well-being, normal examination, and blood tests, a diagnosis of coeliac disease seems unlikely in this case.

Before starting BiPAP, it is important for patients with COPD to have already started maximum medical therapy. This includes receiving supplemental oxygen, using nebulizers with salbutamol and ipratropium, taking steroids and antibiotics if necessary, and potentially receiving IV bronchodilators. Additionally, patients should meet the blood gas requirements of having a pH level below 7.35 and a pCO2 level above 6 Kpa. Another criteria for initiating NIV is having a respiratory rate higher than 23.

Further Reading:

Mechanical ventilation is the use of artificial means to assist or replace spontaneous breathing. It can be invasive, involving instrumentation inside the trachea, or non-invasive, where there is no instrumentation of the trachea. Non-invasive mechanical ventilation (NIV) in the emergency department typically refers to the use of CPAP or BiPAP.

CPAP, or continuous positive airways pressure, involves delivering air or oxygen through a tight-fitting face mask to maintain a continuous positive pressure throughout the patient’s respiratory cycle. This helps maintain small airway patency, improves oxygenation, decreases airway resistance, and reduces the work of breathing. CPAP is mainly used for acute cardiogenic pulmonary edema.

BiPAP, or biphasic positive airways pressure, also provides positive airway pressure but with variations during the respiratory cycle. The pressure is higher during inspiration than expiration, generating a tidal volume that assists ventilation. BiPAP is mainly indicated for type 2 respiratory failure in patients with COPD who are already on maximal medical therapy.

The pressure settings for CPAP typically start at 5 cmH2O and can be increased to a maximum of 15 cmH2O. For BiPAP, the starting pressure for expiratory pressure (EPAP) or positive end-expiratory pressure (PEEP) is 3-5 cmH2O, while the starting pressure for inspiratory pressure (IPAP) is 10-15 cmH2O. These pressures can be titrated up if there is persisting hypoxia or acidosis.

In terms of lung protective ventilation, low tidal volumes of 5-8 ml/kg are used to prevent atelectasis and reduce the risk of lung injury. Inspiratory pressures (plateau pressure) should be kept below 30 cm of water, and permissible hypercapnia may be allowed. However, there are contraindications to lung protective ventilation, such as unacceptable levels of hypercapnia, acidosis, and hypoxemia.

Overall, mechanical ventilation, whether invasive or non-invasive, is used in various respiratory and non-respiratory conditions to support or replace spontaneous breathing and improve oxygenation and ventilation.

Fragility fractures occur when a person experiences a fracture from a force that would not typically cause a fracture, such as a fall from a standing height or less. The most common areas for fragility fractures are the vertebrae, hip, and wrist. Osteoporosis is diagnosed when a patient’s bone mineral density, measured by a T-score on a DEXA scan, is -2.5 standard deviations or below. This T-score compares the patient’s bone density to the peak bone density of a population. In women over 75 years old, osteoporosis can be assumed without a DEXA scan. Osteopenia is diagnosed when a patient’s T-score is between -1 and -2.5 standard deviations below peak bone density. Risk factors for fractures include a family history of hip fractures, excessive alcohol consumption, and rheumatoid arthritis. Low bone mineral density can be indicated by a BMI below 22 kg/m2, untreated menopause, and conditions causing prolonged immobility or certain medical conditions. Medications used to prevent osteoporotic fractures in postmenopausal women include alendronate, risedronate, etidronate, and strontium ranelate. Raloxifene is not used for primary prevention. Alendronate is typically the first-choice medication and is recommended for women over 70 years old with confirmed osteoporosis and either a risk factor for fracture or low bone mineral density. Women over 75 years old with two risk factors or two indicators of low bone mineral density may be assumed to have osteoporosis without a DEXA scan. Other pharmacological interventions can be tried if alendronate is not tolerated.

In the blood tests, certain findings can support a diagnosis of glandular fever. One of these findings is lymphocytosis, which refers to an increased number of lymphocytes in the blood. Lymphocytes are a type of white blood cell that plays a crucial role in the immune response. In glandular fever, the Epstein-Barr virus (EBV) is the most common cause, and it primarily infects and activates lymphocytes, leading to their increased numbers in the blood.

On the other hand, neutropenia (a decreased number of neutrophils) and neutrophilia (an increased number of neutrophils) are not typically associated with glandular fever. Neutrophils are another type of white blood cell that helps fight off bacterial infections. In glandular fever, the primary involvement is with lymphocytes rather than neutrophils.

Monocytosis, which refers to an increased number of monocytes, can also be seen in glandular fever. Monocytes are another type of white blood cell that plays a role in the immune response. Their increased numbers can be a result of the immune system’s response to the Epstein-Barr virus.

Eosinophilia, an increased number of eosinophils, is not commonly associated with glandular fever. Eosinophils are white blood cells involved in allergic reactions and parasitic infections, and their elevation is more commonly seen in those conditions.

In summary, the presence of lymphocytosis and possibly monocytosis in the blood tests would support a diagnosis of glandular fever, while neutropenia, neutrophilia, and eosinophilia are less likely to be associated with this condition.

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.

Recurrent or chronic tonsillitis is a clear indication for tonsillectomy, which is the surgical removal of the palatine tonsils. One common complication of this procedure is bleeding, which occurs in approximately 0.5-2% of cases. The bleeding that occurs after tonsillectomy is typically venous in nature and most frequently originates from the external palatine vein. This vein drains the lateral tonsillar region and ultimately empties into the facial vein. Additionally, bleeding can also arise from the tonsillar branch of the facial artery, which supplies the inferior pole of the palatine tonsil.

A varicocele is a condition characterized by the presence of varicose veins in the pampiniform plexus of the cord and scrotum. It is more commonly observed in the left testis compared to the right and may be linked to infertility. The primary reason for this association is believed to be the elevated temperature of the testis caused by the presence of varicosities.

Typically, individuals with varicocele experience a dull ache in the testis, which tends to worsen after physical activity or towards the end of the day. The scrotum is often described as feeling like a bag of worms. While the varicocele cannot usually be detected when the patient is lying down, it can often be identified during examination while standing. It is felt as a poorly defined, non-transilluminable mass that is clearly separate from the testis and is located above and behind it. The dilation of the varicocele increases when the Valsalva maneuver is performed, and a cough impulse may also be present.

Conservative treatment is typically recommended for varicocele, with surgery being reserved for severe cases only.

These situations are uncommon, but it is crucial to have a plan in place for dealing with them when they arise. This emphasizes the importance of having strong history taking skills and the ability to problem-solve.

Based on the information available, it appears that the patient may have ingested a significant amount of paracetamol, putting them at risk of toxic effects. It would be helpful to have a calm conversation with the patient to understand their perspective, as they may have a fear of needles and may not want any blood tests done.

If there are any family members or a next of kin present, it might be worth giving them some time with the patient to see if they can persuade them to change their mind. If none of these approaches are successful, it is necessary to assess the patient’s mental capacity to make the decision to decline treatment. It is important to remember that capacity can vary depending on the situation and decision at hand.

If it is determined that the patient lacks the capacity to make the decision to decline treatment, there may be a possibility of providing care against their expressed wishes. In such cases, it is advisable to involve the mental health team to formally assess for evidence of mental illness. This assessment may strengthen the case for the patient to be sectioned, which would allow certain actions to be taken against their wishes, including treating them for the effects of their mental illness, which in this case includes addressing the overdose.