The intravascular volume of an infant is approximately 80 ml/kg, while in older children it is around 70 ml/kg. Dehydration itself does not lead to death, but shock can. Shock can occur when there is a loss of 20 ml/kg from the intravascular space, whereas clinical dehydration is only noticeable after total losses greater than 25 ml/kg.

The table below summarizes the maintenance fluid requirements for well, normal children based on their body weight:

Bodyweight: First 10 kg
Daily fluid requirement: 100 ml/kg
Hourly fluid requirement: 4 ml/kg

Bodyweight: Second 10 kg
Daily fluid requirement: 50 ml/kg
Hourly fluid requirement: 2 ml/kg

Bodyweight: Subsequent kg
Daily fluid requirement: 20 ml/kg
Hourly fluid requirement: 1 ml/kg

In general, if a child shows clinical signs of dehydration without shock, they can be assumed to be 5% dehydrated. If shock is also present, it can be assumed that they are 10% dehydrated or more. 5% dehydration means that the body has lost 5 g per 100 g body weight, which is equivalent to 50 ml/kg of fluid. Therefore, 10% dehydration implies a loss of 100 ml/kg of fluid.

In the case of this child, they are in shock and should receive a 20 ml/kg fluid bolus. Therefore, the initial volume of fluid to administer should be 20 x 8 ml = 160 ml.

The clinical features of dehydration and shock are summarized in the table below:

Dehydration (5%):
– Appears ‘unwell’
– Normal heart rate or tachycardia
– Normal respiratory rate or tachypnea
– Normal peripheral pulses
– Normal or mildly prolonged capillary refill time (CRT)
– Normal blood pressure
– Warm extremities
– Decreased urine output
– Reduced skin turgor
– Sunken eyes
– Depressed fontanelle
– Dry mucous membranes

Clinical shock (10%):
– Pale, lethargic, mottled appearance
– Tachycardia
– Tachypnea
– Weak peripheral pulses
– Prolonged capillary refill time (CRT)
– Hypotension
– Cold extremities
– Decreased urine output
– Decreased level of consciousness

Cardiac arrest during pregnancy is a rare occurrence, happening in approximately 16 out of every 100,000 live births. It is crucial to consider both the mother and the fetus when dealing with cardiac arrest in pregnancy, as the best way to ensure a positive outcome for the fetus is by effectively resuscitating the mother.

The main causes of cardiac arrest during pregnancy include pre-existing cardiac disease, pulmonary embolism, hemorrhage, ectopic pregnancy, hypertensive disorders of pregnancy, amniotic fluid embolism, and suicide. Many cardiovascular problems associated with pregnancy are caused by compression of the inferior vena cava.

To prevent decompensation or potential cardiac arrest during pregnancy, it is important to follow these steps when dealing with a distressed or compromised pregnant patient:

– Place the patient in the left lateral position or manually displace the uterus to the left.
– Administer high-flow oxygen, guided by pulse oximetry.
– Give a fluid bolus if there is low blood pressure or signs of hypovolemia.
– Re-evaluate the need for any medications currently being administered.
– Seek expert help and involve obstetric and neonatal specialists early.
– Identify and treat the underlying cause.

In the event of cardiac arrest during pregnancy, in addition to following the standard guidelines for basic and advanced life support, the following modifications should be made:

– Immediately call for expert help, including an obstetrician, anesthetist, and neonatologist.
– Start CPR according to the standard ALS guidelines, but adjust the hand position slightly higher on the sternum.
– Ideally establish IV or IO access above the diaphragm to account for potential compression of the inferior vena cava.
– Manually displace the uterus to the left to relieve caval compression.
– Tilt the table to the left side (around 15-30 degrees of tilt).
– Perform early tracheal intubation to reduce the risk of aspiration (seek assistance from an expert anesthetist).
– Begin preparations for an emergency Caesarean section.

A perimortem Caesarean section should be performed within 5 minutes of the onset of cardiac arrest. This delivery will alleviate caval compression and increase the chances of successful resuscitation by improving venous return during CPR. It will also maximize the chances of the infant’s survival, as the best survival rate occurs when delivery is achieved within 5 minutes of the mother’s cardiac arrest.

Salicylate poisoning often leads to a metabolic acidosis characterized by a high anion gap. The patient in question is experiencing this type of acid-base disturbance. This particular acid-base imbalance is typically seen in cases of poisoning with substances such as glycols (ethylene and propylene), salicylates (aspirin), paracetamol, methanol, isoniazid, and paraldehyde.

Further Reading:

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

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

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

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

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

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

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

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

Activated charcoal is a commonly used substance for decontamination in cases of poisoning. Its main function is to adsorb the molecules of the ingested toxin onto its surface.

Activated charcoal is a chemically inert form of carbon. It is a fine black powder that has no odor or taste. It is produced by subjecting carbonaceous matter to high heat, a process known as pyrolysis, and then treating it with a zinc chloride solution to increase its concentration. This process creates a network of pores within the charcoal, giving it a large absorptive area of approximately 3,000 m2/g. This allows it to effectively inhibit the absorption of toxins by up to 50%.

The usual dose of activated charcoal is 50 grams for adults and 1 gram per kilogram of body weight for children. It can be administered orally or through a nasogastric tube. It is important to administer it within one hour of ingestion, and it may be repeated after one hour if necessary.

However, there are certain situations where activated charcoal should not be used. These include cases where the patient is unconscious or in a coma, as there is a risk of aspiration. It should also be avoided if seizures are imminent, as there is a risk of aspiration. Additionally, if there is reduced gastrointestinal motility, activated charcoal should not be used to prevent the risk of obstruction.

Activated charcoal is effective in treating overdose with certain drugs and toxins, such as aspirin, paracetamol, barbiturates, tricyclic antidepressants, digoxin, amphetamines, morphine, cocaine, and phenothiazines. However, it is ineffective in cases of overdose with iron, lithium, boric acid, cyanide, ethanol, ethylene glycol, methanol, malathion, DDT, carbamate, hydrocarbon, strong acids, or alkalis.

There are potential adverse effects associated with the use of activated charcoal. These include nausea and vomiting, diarrhea, constipation, bezoar formation (a mass of undigested material that can cause blockages), bowel obstruction, pulmonary aspiration (inhalation of charcoal into the lungs), and impaired absorption of oral medications or antidotes.

The patient’s history aligns with a generalized tonic-clonic seizure. The observer of the incident provided a detailed description, which is crucial in diagnosing epilepsy.

Diagnosing epilepsy can sometimes rely solely on the patient’s history. It is common to ask the patient to maintain a seizure diary to identify patterns and potential triggers. Additionally, EEG tests, along with an MRI scan or CT scan of the brain, can provide further insight into the type and possible cause of the seizures.

For the treatment of men with lower urinary tract infection (UTI), it is recommended to offer an immediate prescription of antibiotics. However, certain factors should be taken into account. This includes considering previous urine culture and susceptibility results, as well as any history of antibiotic use that may have led to the development of resistant bacteria.

Before starting antibiotics, it is important to obtain a midstream urine sample from men and send it for culture and susceptibility testing. This will help determine the most appropriate choice of antibiotic.

Once the microbiological results are available, it is necessary to review the initial choice of antibiotic. If the bacteria are found to be resistant and symptoms are not improving, it is recommended to switch to a narrow-spectrum antibiotic whenever possible.

The first-choice antibiotics for men with lower UTI are trimethoprim 200 mg taken orally twice daily for 7 days, or nitrofurantoin 100 mg modified-release taken orally twice daily for 7 days if the estimated glomerular filtration rate (eGFR) is above 45 ml/minute.

If there is no improvement in lower UTI symptoms after at least 48 hours on the first-choice antibiotics, or if the first-choice is not suitable, it is important to consider alternative diagnoses and follow the recommendations in the NICE guidelines on pyelonephritis (acute): antimicrobial prescribing or prostatitis (acute): antimicrobial prescribing. The choice of antibiotic should be based on recent culture and susceptibility results.

Alteplase (rt-pA) is recommended for the treatment of acute ischaemic stroke in adults if it is administered as soon as possible within 4.5 hours of the onset of stroke symptoms. It is important to exclude intracranial haemorrhage through appropriate imaging techniques before starting the treatment. The initial dose of alteplase is 0.9 mg/kg, with a maximum dose of 90 mg. This dose should be given intravenously over 60 minutes, with the initial 10% administered by intravenous injection and the remainder by intravenous infusion. In the case of a patient weighing 120 kg, the maximum dose of 90 mg should be administered. For more information, please refer to the NICE guidelines on stroke and transient ischaemic attack in individuals over 16 years old.

To estimate the total body surface area of burn, we need to consider the rule of nines. This rule divides the body into different regions, each representing a certain percentage of the total body surface area. According to the rule of nines, the left arm accounts for 9% of the total body surface area. Therefore, the estimated total body surface area of burn in this patient is 9%.

Further Reading:

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

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

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

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

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

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

Digoxin-specific antibody (DigiFab) is an antidote used to counteract digoxin overdose. It is a purified and sterile preparation of digoxin-immune ovine Fab immunoglobulin fragments. These fragments are derived from healthy sheep that have been immunized with a digoxin derivative called digoxin-dicarboxymethoxylamine (DDMA). DDMA is a digoxin analogue that contains the essential cyclopentanoperhydrophenanthrene: lactone ring moiety coupled to keyhole limpet hemocyanin (KLH).

DigiFab has a higher affinity for digoxin compared to the affinity of digoxin for its sodium pump receptor, which is believed to be the receptor responsible for its therapeutic and toxic effects. When administered to a patient who has overdosed on digoxin, DigiFab binds to digoxin molecules, reducing the levels of free digoxin in the body. This shift in equilibrium away from binding to the receptors helps to reduce the cardiotoxic effects of digoxin. The Fab-digoxin complexes are then eliminated from the body through the kidney and reticuloendothelial system.

The indications for using DigiFab in cases of acute and chronic digoxin toxicity are summarized below:

Acute digoxin toxicity:
– Cardiac arrest
– Life-threatening arrhythmia
– Potassium level >5 mmol/l
– Ingestion of >10 mg of digoxin (in adults)
– Ingestion of >4 mg of digoxin (in children)
– Digoxin level >12 ng/ml

Chronic digoxin toxicity:
– Cardiac arrest
– Life-threatening arrhythmia
– Significant gastrointestinal symptoms
– Symptoms of digoxin toxicity in the presence of renal failure

This patient presents with a noticeable mass at the top of the right lung, which is clearly visible on the chest X-ray. Based on the symptoms and clinical presentation, it is highly likely that this is a Pancoast tumor, and the overall diagnosis is Pancoast syndrome.

A Pancoast tumor is a type of tumor that develops at the apex of either the right or left lung. It typically spreads to nearby tissues such as the ribs and vertebrae. The majority of Pancoast tumors are classified as non-small cell cancers.

Pancoast syndrome occurs when the tumor invades various structures and tissues around the thoracic inlet. This includes the invasion of the cervical sympathetic plexus on the same side as the tumor, leading to the development of Horner’s syndrome. Additionally, there may be reflex sympathetic dystrophy in the arm on the affected side, resulting in increased sensitivity to touch and changes in the skin.

Patients with Pancoast syndrome may also experience shoulder and arm pain due to the tumor invading the brachial plexus roots C8-T1. This can lead to muscle wasting in the hand and tingling sensations in the inner side of the arm. In some cases, there may be involvement of the unilateral recurrent laryngeal nerve, causing unilateral vocal cord paralysis and resulting in a hoarse voice and/or a bovine cough. Phrenic nerve involvement is less common but can also occur.

Horner’s syndrome, which is a key feature of Pancoast syndrome, is caused by compression of the sympathetic chain from the hypothalamus to the orbit. The three main symptoms of Horner’s syndrome are drooping of the eyelid (ptosis), constriction of the pupil (pupillary miosis), and lack of sweating on the forehead (anhydrosis).

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.

Central retinal vein occlusion (CRVO) is a condition that usually leads to painless, one-sided vision loss. When examining the retina, it may appear similar to a ‘pizza thrown against a wall’, with swollen retinal veins, swelling of the optic disc, numerous flame-shaped hemorrhages, and cotton wool spots. Hypertension is present in about 65% of CRVO cases and is more common in individuals aged 65 and above.

On the other hand, branch retinal vein occlusion (BRVO) typically affects only one section of the retina, resulting in visual field deficits in that specific quadrant rather than complete vision loss.

Insulin is known to have several effects on the body. One of its important functions is to increase blood pH. In patients with diabetic ketoacidosis (DKA), their blood pH is low due to acidosis. Insulin helps to correct this by reducing the levels of free fatty acids in the blood, which are responsible for the production of ketone bodies that contribute to acidosis. By doing so, insulin can increase the blood pH.

Additionally, insulin plays a role in regulating glucose levels. It facilitates the movement of glucose from the blood into cells, leading to a decrease in blood glucose levels and an increase in intracellular glucose.

Furthermore, insulin affects the balance of sodium and potassium in the body. It decreases the excretion of sodium by the kidneys and drives potassium from the blood into cells, resulting in a reduction in blood potassium levels. However, it is important to monitor potassium levels closely during insulin infusions, as if they become too low (hypokalemia), the infusion may need to be stopped.

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.

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.

Le Fort III fractures can be distinguished from Le Fort II fractures by the presence of damage to the zygomatic arch.

Further Reading:

The Le Fort fracture classification describes three fracture patterns seen in midface fractures, all involving the maxilla and pterygoid plate disruption. As the classification grading increases, the anatomic level of the maxillary fracture ascends from inferior to superior.

Le Fort I fractures, also known as floating palate fractures, typically result from a downward blow struck above the upper dental row. Signs include swelling of the upper lip, bruising to the upper buccal sulcus, malocclusion, and mobile upper teeth.

Le Fort II fractures, also known as floating maxilla fractures, are typically the result of a forceful blow to the midaxillary area. Signs include a step deformity at the infraorbital margin, oedema over the middle third of the face, sensory disturbance of the cheek, and bilateral circumorbital ecchymosis.

Le Fort III fractures, also known as craniofacial dislocation or floating face fractures, are typically the result of high force blows to the nasal bridge or upper maxilla. These fractures involve the zygomatic arch and extend through various structures in the face. Signs include tenderness at the frontozygomatic suture, lengthening of the face, enophthalmos, and bilateral circumorbital ecchymosis.

Management of Le Fort fractures involves securing the airway as a priority, following the ABCDE approach, and identifying and managing other injuries, especially cervical spine injuries. Severe bleeding may occur and should be addressed appropriately. Surgery is almost always required, and patients should be referred to maxillofacial surgeons. Other specialties, such as neurosurgery and ophthalmology, may need to be involved depending on the specific case.

In this case, the administration of the local anesthetic used for the Bier’s block may have caused the patient’s blood to convert hemoglobin into methemoglobin, resulting in the observed skin color change.

Further Reading:

Bier’s block is a regional intravenous anesthesia technique commonly used for minor surgical procedures of the forearm or for reducing distal radius fractures in the emergency department (ED). It is recommended by NICE as the preferred anesthesia block for adults requiring manipulation of distal forearm fractures in the ED.

Before performing the procedure, a pre-procedure checklist should be completed, including obtaining consent, recording the patient’s weight, ensuring the resuscitative equipment is available, and monitoring the patient’s vital signs throughout the procedure. The air cylinder should be checked if not using an electronic machine, and the cuff should be checked for leaks.

During the procedure, a double cuff tourniquet is placed on the upper arm, and the arm is elevated to exsanguinate the limb. The proximal cuff is inflated to a pressure 100 mmHg above the systolic blood pressure, up to a maximum of 300 mmHg. The time of inflation and pressure should be recorded, and the absence of the radial pulse should be confirmed. 0.5% plain prilocaine is then injected slowly, and the time of injection is recorded. The patient should be warned about the potential cold/hot sensation and mottled appearance of the arm. After injection, the cannula is removed and pressure is applied to the venipuncture site to prevent bleeding. After approximately 10 minutes, the patient should have anesthesia and should not feel pain during manipulation. If anesthesia is successful, the manipulation can be performed, and a plaster can be applied by a second staff member. A check x-ray should be obtained with the arm lowered onto a pillow. The tourniquet should be monitored at all times, and the cuff should be inflated for a minimum of 20 minutes and a maximum of 45 minutes. If rotation of the cuff is required, it should be done after the manipulation and plaster application. After the post-reduction x-ray is satisfactory, the cuff can be deflated while observing the patient and monitors. Limb circulation should be checked prior to discharge, and appropriate follow-up and analgesia should be arranged.

There are several contraindications to performing Bier’s block, including allergy to local anesthetic, hypertension over 200 mm Hg, infection in the limb, lymphedema, methemoglobinemia, morbid obesity, peripheral vascular disease, procedures needed in both arms, Raynaud’s phenomenon, scleroderma, severe hypertension and sickle cell disease.

The posterior interosseous nerve (PIN) is a motor branch of the radial nerve that is located deep within the body. It emerges above the elbow, between the brachioradialis and brachialis muscles, and then divides into two branches: the superficial radial nerve and the PIN. This division occurs at the lateral epicondyle level. As it travels through the forearm, the PIN passes through the supinator muscle, moving from the front to the back surface. In about 30% of individuals, it also passes through a fibrotendinous structure called the arcade of Frohse, which is located below the supinator muscle. The PIN is responsible for supplying all of the extrinsic wrist extensors, with the exception of the extensor carpi radialis longus muscle.

There are several potential causes of damage to the PIN. Fractures, such as a Monteggia fracture, can lead to injury. Inflammation of the radiocapitellar joint, known as radiocapitellar joint synovitis, can also be a contributing factor. Tumors, such as lipomas, may cause damage as well. Additionally, entrapment of the PIN within the arcade of Frohse can result in a condition known as PIN syndrome.

It is important to note that injury to the PIN can be easily distinguished from injury to the radial nerve in other areas of the arm, such as the spiral groove. This is because there will be no sensory involvement and no wrist drop, as the extensor carpi radialis longus muscle remains unaffected.

The anterior interosseous nerve (AIN) is a branch of the median nerve. It primarily functions as a motor nerve, supplying the flexor pollicis longus muscle, the lateral half of the flexor digitorum profundus muscle, and the pronator quadratus muscle. Damage to the AIN can result in weakness and difficulty moving the index and middle fingers.

Atropine acts as a blocker for muscarinic acetylcholine receptors, making it an antagonist. It is commonly administered during peri-arrest bradycardia. In adults, a dose of 500 mcg is given every 3-5 minutes, with a maximum total dose of 3mg. On the other hand, the initial intravenous dose of amiodarone is 300 mg. Amiodarone works by prolonging repolarization and decreasing myocardial excitability. Additionally, lidocaine functions by blocking sodium channels.

Further Reading:

In the management of respiratory and cardiac arrest, several drugs are commonly used to help restore normal function and improve outcomes. Adrenaline is a non-selective agonist of adrenergic receptors and is administered intravenously at a dose of 1 mg every 3-5 minutes. It works by causing vasoconstriction, increasing systemic vascular resistance (SVR), and improving cardiac output by increasing the force of heart contraction. Adrenaline also has bronchodilatory effects.

Amiodarone is another drug used in cardiac arrest situations. It blocks voltage-gated potassium channels, which prolongs repolarization and reduces myocardial excitability. The initial dose of amiodarone is 300 mg intravenously after 3 shocks, followed by a dose of 150 mg after 5 shocks.

Lidocaine is an alternative to amiodarone in cardiac arrest situations. It works by blocking sodium channels and decreasing heart rate. The recommended dose is 1 mg/kg by slow intravenous injection, with a repeat half of the initial dose after 5 minutes. The maximum total dose of lidocaine is 3 mg/kg.

Magnesium sulfate is used to reverse myocardial hyperexcitability associated with hypomagnesemia. It is administered intravenously at a dose of 2 g over 10-15 minutes. An additional dose may be given if necessary, but the maximum total dose should not exceed 3 g.

Atropine is an antagonist of muscarinic acetylcholine receptors and is used to counteract the slowing of heart rate caused by the parasympathetic nervous system. It is administered intravenously at a dose of 500 mcg every 3-5 minutes, with a maximum dose of 3 mg.

Naloxone is a competitive antagonist for opioid receptors and is used in cases of respiratory arrest caused by opioid overdose. It has a short duration of action, so careful monitoring is necessary. The initial dose of naloxone is 400 micrograms, followed by 800 mcg after 1 minute. The dose can be gradually escalated up to 2 mg per dose if there is no response to the preceding dose.

It is important for healthcare professionals to have knowledge of the pharmacology and dosing schedules of these drugs in order to effectively manage respiratory and cardiac arrest situations.

Cytochrome p450 enzyme inducers have the ability to hinder the effects of warfarin, leading to a decrease in INR levels. To remember the commonly encountered cytochrome p450 enzyme inducers, the mnemonic PC BRASS can be utilized. Each letter in the mnemonic represents a specific inducer: P for Phenytoin, C for Carbamazepine, B for Barbiturates, R for Rifampicin, A for Alcohol (chronic ingestion), S for Sulphonylureas, and S for Smoking. These inducers can have an impact on the effectiveness of warfarin and should be taken into consideration when prescribing or using this medication.

The most probable diagnosis in this case is septic arthritis, which occurs when an infectious agent invades a joint and causes pus formation. The patient’s recent travel to Bangkok, presence of a vesicular rash on the trunk, and the identification of Gram-negative diplococci support this diagnosis.

Septic arthritis is characterized by several clinical features. These include pain in the affected joint, redness, warmth, and swelling of the joint, and difficulty in moving the joint. Patients may also experience fever and systemic upset.

The most common cause of septic arthritis is Staphylococcus aureus. Other bacteria that can lead to this condition include Streptococcus spp., Haemophilus influenzae, Neisseria gonorrhoea (typically seen in sexually active young adults with macules or vesicles on the trunk), and Escherichia coli (common in intravenous drug users, the elderly, and seriously ill individuals).

According to the current recommendations by NICE (National Institute for Health and Care Excellence) and the BNF (British National Formulary), the treatment for septic arthritis involves the following approaches. Flucloxacillin is the first-line antibiotic. In cases of penicillin allergy, clindamycin is recommended. If there is suspicion of MRSA (methicillin-resistant Staphylococcus aureus), vancomycin should be used. For suspected gonococcal arthritis or Gram-negative infection, cefotaxime is the preferred choice. The suggested duration of treatment is 4-6 weeks, although it may be longer if the infection is complicated.

Patients with HSP commonly experience symptoms such as abdominal pain, gastrointestinal issues like nausea and diarrhea, joint inflammation in multiple joints (polyarthritis), and involvement of the kidneys.

Further Reading:

Henoch-Schonlein purpura (HSP) is a small vessel vasculitis that is mediated by IgA. It is commonly seen in children following an infection, with 90% of cases occurring in children under 10 years of age. The condition is characterized by a palpable purpuric rash, abdominal pain, gastrointestinal upset, and polyarthritis. Renal involvement occurs in approximately 50% of cases, with renal impairment typically occurring within 1 day to 1 month after the onset of other symptoms. However, renal impairment is usually mild and self-limiting, although 10% of cases may have serious renal impairment at presentation and 1% may progress to end-stage kidney failure long term. Treatment for HSP involves analgesia for arthralgia, and treatment for nephropathy is generally supportive. The prognosis for HSP is usually excellent, with the condition typically resolving fully within 4 weeks, especially in children without renal involvement. However, around 1/3rd of patients may experience relapses, which can occur for several months.

For adults and children over the age of 12 who are suspected to have glandular fever and have a normal immune system, it is recommended to conduct a Full Blood Count (FBC) and a monospot test during the second week of the illness. The timing and choice of investigations for glandular fever vary depending on the patient’s age, immune system status, and duration of symptoms. For children under the age of 12 and individuals with compromised immune systems, it is advised to perform a blood test for Epstein-Barr virus (EBV) viral serology after at least 7 days of illness. However, for immunocompetent adults and children older than 12, a FBC with differential white cell count and a monospot test (heterophile antibodies) should be conducted during the second week of the illness.

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.

Henry’s law describes the correlation between the quantity of dissolved gas in a liquid and its partial pressure above the liquid. According to Henry’s law, the amount of gas dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid. In the case of nitrogen narcosis, as the patient descends deeper into the water, the pressure increases, causing more nitrogen to dissolve in the bloodstream. As the patient ascends, the pressure decreases, leading to a decrease in the amount of dissolved nitrogen and improvement in symptoms.

Further Reading:

Decompression illness (DCI) is a term that encompasses both decompression sickness (DCS) and arterial gas embolism (AGE). When diving underwater, the increasing pressure causes gases to become more soluble and reduces the size of gas bubbles. As a diver ascends, nitrogen can come out of solution and form gas bubbles, leading to decompression sickness or the bends. Boyle’s and Henry’s gas laws help explain the changes in gases during changing pressure.

Henry’s law states that the amount of gas that dissolves in a liquid is proportional to the partial pressure of the gas. Divers often use atmospheres (ATM) as a measure of pressure, with 1 ATM being the pressure at sea level. Boyle’s law states that the volume of gas is inversely proportional to the pressure. As pressure increases, volume decreases.

Decompression sickness occurs when nitrogen comes out of solution as a diver ascends. The evolved gas can physically damage tissue by stretching or tearing it as bubbles expand, or by provoking an inflammatory response. Joints and spinal nervous tissue are commonly affected. Symptoms of primary damage usually appear immediately or soon after a dive, while secondary damage may present hours or days later.

Arterial gas embolism occurs when nitrogen bubbles escape into the arterial circulation and cause distal ischemia. The consequences depend on where the embolism lodges, ranging from tissue ischemia to stroke if it lodges in the cerebral arterial circulation. Mechanisms for distal embolism include pulmonary barotrauma, right to left shunt, and pulmonary filter overload.

Clinical features of decompression illness vary, but symptoms often appear within six hours of a dive. These can include joint pain, neurological symptoms, chest pain or breathing difficulties, rash, vestibular problems, and constitutional symptoms. Factors that increase the risk of DCI include diving at greater depth, longer duration, multiple dives close together, problems with ascent, closed rebreather circuits, flying shortly after diving, exercise shortly after diving, dehydration, and alcohol use.

Diagnosis of DCI is clinical, and investigations depend on the presentation. All patients should receive high flow oxygen, and a low threshold for ordering a chest X-ray should be maintained. Hydration is important, and IV fluids may be necessary. Definitive treatment is recompression therapy in a hyperbaric oxygen chamber, which should be arranged as soon as possible. Entonox should not be given, as it will increase the pressure effect in air spaces.

Here is a revised version of the guidance on the management of bacterial conjunctivitis:

– It is important to inform the patient that most cases of bacterial conjunctivitis will resolve on their own within 5-7 days without any treatment.
– However, if the condition is severe or if there is a need for rapid resolution, topical antibiotics may be prescribed. In some cases, a delayed treatment strategy may be appropriate, and the patient should be advised to start using topical antibiotics if their symptoms have not improved within 3 days.
– There are several options for topical antibiotics, including Chloramphenicol 0.5% drops (to be applied every 2 hours for 2 days, then 4 times daily for 5 days) and Chloramphenicol 1% ointment (to be applied four times daily for 2 days, then twice daily for 5 days). Fusidic acid 1% eye drops can also be used as a second-line treatment, to be applied twice daily for 7 days.
– It is important to note that there is no recommended exclusion period from school, nursery, or childminders for isolated cases of bacterial conjunctivitis. However, some institutions may have their own exclusion policies.
– Provide the patient with written information and explain the red flags that indicate the need for an urgent review.
– Arrange a follow-up appointment to confirm the diagnosis and ensure that the symptoms have resolved.
– If the patient returns with ongoing symptoms, it may be necessary to send swabs for viral PCR (to test for adenovirus and Herpes simplex) and bacterial culture. Empirical topical antibiotics may also be prescribed if they have not been previously given.
– Consider referring the patient to ophthalmology if the symptoms persist for more than 7 to 10 days after initiating treatment.

For more information, you can refer to the NICE Clinical Knowledge Summary on Infective Conjunctivitis.

Antihistamines do not help in treating the life-threatening aspects of anaphylaxis and should not be used instead of adrenaline. However, they can be used to relieve symptoms such as skin reactions and itching once the patient’s condition has stabilized. The appropriate dose of cetirizine for children between the ages of 2 and 6 is 2.5-5 mg. It is important to note that chlorpheniramine is no longer recommended. The recommended doses of oral cetirizine for different age groups are as follows: less than 2 years – 250 micrograms/kg, 2-6 years – 2.5-5 mg, 6-11 years – 5-10 mg, 12 years and older – 10-20 mg.

Further Reading:

Anaphylaxis is a severe and life-threatening allergic reaction that affects the entire body. It is characterized by a rapid onset and can lead to difficulty breathing, low blood pressure, and loss of consciousness. In paediatrics, anaphylaxis is often caused by food allergies, with nuts being the most common trigger. Other causes include drugs and insect venom, such as from a wasp sting.

When treating anaphylaxis, time is of the essence and there may not be enough time to look up medication doses. Adrenaline is the most important drug in managing anaphylaxis and should be administered as soon as possible. The recommended doses of adrenaline vary based on the age of the child. For children under 6 months, the dose is 150 micrograms, while for children between 6 months and 6 years, the dose remains the same. For children between 6 and 12 years, the dose is increased to 300 micrograms, and for adults and children over 12 years, the dose is 500 micrograms. Adrenaline can be repeated every 5 minutes if necessary.

The preferred site for administering adrenaline is the anterolateral aspect of the middle third of the thigh. This ensures quick absorption and effectiveness of the medication. It is important to follow the Resuscitation Council guidelines for anaphylaxis management, as they have recently been updated.

In some cases, 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. This can help confirm the diagnosis and guide further management.

Overall, prompt recognition and administration of adrenaline are crucial in managing anaphylaxis in paediatrics. Following the recommended doses and guidelines can help ensure the best outcomes for patients experiencing this severe allergic reaction.

Prussian blue is a substance that helps remove radioactive caesium from the body, a process known as decorporation. It is specifically effective for caesium exposure. When taken orally, Prussian blue binds to the radioactive caesium, forming a compound that can be excreted from the body, preventing further absorption. By using Prussian blue, the whole body radiation dose can be reduced by approximately two-thirds. Radioactive caesium is utilized in various medical, geological, and industrial applications, although incidents of environmental contamination are rare, they have been reported in Western Australia and Eastern Thailand during the first quarter of 2023.

Further Reading:

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

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

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

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

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

In managing patients with carbon monoxide poisoning, the primary intervention is providing 100% oxygen. This is because carbon monoxide has a higher affinity for hemoglobin than oxygen, leading to decreased oxygen delivery to tissues. By administering 100% oxygen, the patient is able to displace carbon monoxide from hemoglobin and increase oxygen levels in the blood, which is crucial for the patient’s recovery.

Further Reading:

Carbon monoxide (CO) is a dangerous gas that is produced by the combustion of hydrocarbon fuels and can be found in certain chemicals. It is colorless and odorless, making it difficult to detect. In England and Wales, there are approximately 60 deaths each year due to accidental CO poisoning.

When inhaled, carbon monoxide binds to haemoglobin in the blood, forming carboxyhaemoglobin (COHb). It has a higher affinity for haemoglobin than oxygen, causing a left-shift in the oxygen dissociation curve and resulting in tissue hypoxia. This means that even though there may be a normal level of oxygen in the blood, it is less readily released to the tissues.

The clinical features of carbon monoxide toxicity can vary depending on the severity of the poisoning. Mild or chronic poisoning may present with symptoms such as headache, nausea, vomiting, vertigo, confusion, and weakness. More severe poisoning can lead to intoxication, personality changes, breathlessness, pink skin and mucosae, hyperpyrexia, arrhythmias, seizures, blurred vision or blindness, deafness, extrapyramidal features, coma, or even death.

To help diagnose domestic carbon monoxide poisoning, there are four key questions that can be asked using the COMA acronym. These questions include asking about co-habitees and co-occupants in the house, whether symptoms improve outside of the house, the maintenance of boilers and cooking appliances, and the presence of a functioning CO alarm.

Typical carboxyhaemoglobin levels can vary depending on whether the individual is a smoker or non-smoker. Non-smokers typically have levels below 3%, while smokers may have levels below 10%. Symptomatic individuals usually have levels between 10-30%, and severe toxicity is indicated by levels above 30%.

When managing carbon monoxide poisoning, the first step is to administer 100% oxygen. Hyperbaric oxygen therapy may be considered for individuals with a COHb concentration of over 20% and additional risk factors such as loss of consciousness, neurological signs, myocardial ischemia or arrhythmia, or pregnancy. Other management strategies may include fluid resuscitation, sodium bicarbonate for metabolic acidosis, and mannitol for cerebral edema.

Whooping cough is a respiratory infection caused by the bacteria Bordetella pertussis. It is highly contagious and spreads to about 90% of close household contacts. Public Health England (PHE) has identified two priority groups for managing whooping cough contacts. Group 1 includes infants under one year who have received less than three doses of the pertussis vaccine and are at risk of severe infection. Group 2 includes pregnant women at 32 weeks or more, healthcare workers dealing with infants and pregnant women, individuals working with unvaccinated infants under 4 months old, and individuals living with unvaccinated infants under 4 months old.

According to current guidelines, antibiotic prophylaxis with a macrolide antibiotic like erythromycin should only be given to close contacts if the following criteria are met: the index case has had symptoms within the past 21 days and there is a close contact in one of the priority groups. If both criteria are met, all contacts, regardless of age and vaccination status, should be offered chemoprophylaxis. In this case, the mother falls into group 2, so the recommended action is to provide chemoprophylaxis to all household contacts, including the mother, father, and brother. Additionally, those who receive chemoprophylaxis should also consider immunization or a booster dose based on their current vaccination status.

The primary approach to managing nerve gas exposure through medication involves the repeated administration of antidotes. The two antidotes utilized for this purpose are atropine and pralidoxime.

Atropine is the standard anticholinergic medication employed to address the symptoms associated with nerve agent poisoning. It functions as an antagonist for muscarinic acetylcholine receptors, effectively blocking the effects caused by excessive acetylcholine. Initially, a 1.2 mg intravenous bolus of atropine is administered. This dosage is then repeated and doubled every 2-3 minutes until excessive bronchial secretion ceases and miosis (excessive constriction of the pupil) resolves. In some cases, as much as 100 mg of atropine may be necessary.

Pralidoxime (2-PAMCl) is the standard oxime used in the treatment of nerve agent poisoning. Its mechanism of action involves reactivating acetylcholinesterase by scavenging the phosphoryl group attached to the functional hydroxyl group of the enzyme, thereby counteracting the effects of the nerve agent itself. For patients who are moderately or severely poisoned, pralidoxime should be administered intravenously at a dosage of 30 mg/kg of body weight (or 2 g in the case of an adult) over a period of four minutes.

Of all the medications mentioned in this question, only pioglitazone is known to be a potential cause of hypoglycemia. Glucagon, on the other hand, is specifically used as a treatment for hypoglycemia. The remaining medications mentioned are antidiabetic drugs that do not typically lead to hypoglycemia when used alone.

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.

Slapped cheek syndrome, also known as fifth disease or erythema infectiosum, is caused by parvovirus B19. It is most commonly seen in children aged 4-12, but can affect individuals of any age. In the UK, the peak occurrence of this condition is in April and May. Slapped cheek syndrome is contagious, with the period of infectivity occurring before the appearance of the characteristic rash. The rash itself is painless.

Diagnosing slapped cheek syndrome is typically based on clinical presentation, characterized by the sudden onset of bright red cheeks resembling a slap mark. In some cases, a faint rash may also appear on other parts of the body. The rash usually lasts for a few days, but in rare instances, it may persist for a few weeks. Treatment for this condition is usually focused on managing symptoms. Additional symptoms that may accompany the rash include a mild fever and joint pain.

While slapped cheek syndrome is generally mild and resolves on its own, certain groups of individuals require extra caution. Pregnant women, for instance, are at an increased risk of miscarriage if exposed to fifth disease. Patients with sickle cell disease or weakened immune systems also need to take extra precautions.

Patients who have a CENTOR score of 0, 1, or 2 should be given advice on self-care and safety measures. In this case, the patient has a CENTOR score of 1/4 and a FeverPAIN score of 1, indicating that antibiotics are not necessary. The patient should be advised to drink enough fluids, use over-the-counter pain relievers like ibuprofen or paracetamol, try salt water gargling or medicated lozenges, and avoid hot drinks as they can worsen the pain. It is important to inform the patient that if they experience difficulty swallowing, develop a fever above 38ºC, or if their symptoms do not improve after 3 days, they should seek reassessment.

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. can

To insert an IJV line, the patient should be positioned in the Trendelenburg position. This means that the patient should lie on their back with their head tilted down by at least 15 degrees. Additionally, the patient’s head should be turned away or laterally rotated from the side where the cannulation will take place. This positioning helps to distend the neck veins, making it easier to access them for the procedure.

Further Reading:

A central venous catheter (CVC) is a type of catheter that is inserted into a large vein in the body, typically in the neck, chest, or groin. It has several important uses, including CVP monitoring, pulmonary artery pressure monitoring, repeated blood sampling, IV access for large volumes of fluids or drugs, TPN administration, dialysis, pacing, and other procedures such as placement of IVC filters or venous stents.

When inserting a central line, it is ideal to use ultrasound guidance to ensure accurate placement. However, there are certain contraindications to central line insertion, including infection or injury to the planned access site, coagulopathy, thrombosis or stenosis of the intended vein, a combative patient, or raised intracranial pressure for jugular venous lines.

The most common approaches for central line insertion are the internal jugular, subclavian, femoral, and PICC (peripherally inserted central catheter) veins. The internal jugular vein is often chosen due to its proximity to the carotid artery, but variations in anatomy can occur. Ultrasound can be used to identify the vessels and guide catheter placement, with the IJV typically lying superficial and lateral to the carotid artery. Compression and Valsalva maneuvers can help distinguish between arterial and venous structures, and doppler color flow can highlight the direction of flow.

In terms of choosing a side for central line insertion, the right side is usually preferred to avoid the risk of injury to the thoracic duct and potential chylothorax. However, the left side can also be used depending on the clinical situation.

Femoral central lines are another option for central venous access, with the catheter being inserted into the femoral vein in the groin. Local anesthesia is typically used to establish a field block, with lidocaine being the most commonly used agent. Lidocaine works by blocking sodium channels and preventing the propagation of action potentials.

In summary, central venous catheters have various important uses and should ideally be inserted using ultrasound guidance. There are contraindications to their insertion, and different approaches can be used depending on the clinical situation. Local anesthesia is commonly used for central line insertion, with lidocaine being the preferred agent.

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

AKI is categorized into three stages based on specific criteria. In stage 1, there is a rise in creatinine levels of 26 micromol/L or more within 48 hours, or a rise of 50-99% from the baseline within 7 days. Additionally, a urine output of less than 0.5 mL/kg/hour for more than 6 hours is indicative of stage 1 AKI.

Stage 2 AKI is characterized by a creatinine rise of 100-199% from the baseline within 7 days, or a urine output of less than 0.5 mL/kg/hour for more than 12 hours.

The most severe stage, stage 3 AKI, is identified by a creatinine rise of 200% or more from the baseline within 7 days. It can also be diagnosed if the creatinine level reaches 354 micromol/L or more with an acute rise of 26 micromol/L or more within 48 hours, or a rise of 50% or more within 7 days. Additionally, a urine output of less than 0.3 mL/kg/hour for 24 hours or anuria (no urine production) for 12 hours is indicative of stage 3 AKI.

This patient is currently experiencing a secondary haemorrhage after undergoing a dental extraction. There are three different types of haemorrhage that can occur following a dental extraction. The first type is immediate haemorrhage, which happens during the extraction itself. The second type is reactionary haemorrhage, which typically occurs 2-3 hours after the extraction when the vasoconstrictor effects of the local anaesthetic wear off. Lastly, there is secondary haemorrhage, which usually happens at around 48-72 hours after the extraction and is a result of the clot becoming infected.

Otitis externa, also known as swimmer’s ear, is a condition characterized by infection and inflammation of the ear canal. Common symptoms include pain, itching, and discharge from the ear. Upon examination with an otoscope, the ear canal will appear red and there may be pus and debris present.

There are several factors that can increase the risk of developing otitis externa, including skin conditions like psoriasis and eczema. Additionally, individuals who regularly expose their ears to water, such as swimmers, are more prone to this condition.

The most common organisms that cause otitis externa are Pseudomonas aeruginosa (50%), Staphylococcus aureus (23%), Gram-negative bacteria like E.coli (12%), and fungal species like Aspergillus and Candida (12%).

Treatment for otitis externa typically involves the use of topical antibiotic and corticosteroid combinations, such as Betnesol-N or Sofradex. In some cases, when the condition persists, referral to an ear, nose, and throat specialist may be necessary for auditory cleaning and the placement of an antibiotic-soaked wick.

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.

Infective endocarditis is a condition that can be identified by certain signs, although none of them are definitive proof of the disease. The most reliable indicators are the presence of a heart murmur and a fever. However, there are other signs that are commonly associated with infective endocarditis, including splinter hemorrhages, Osler’s nodes, Janeway lesions, and Roth spots. It is important to note that these signs can also appear in other conditions, and they are not always present in patients with infective endocarditis. In fact, each of these signs is typically found in less than a third of patients diagnosed with the disease.

Further Reading:

Infective endocarditis (IE) is an infection that affects the innermost layer of the heart, known as the endocardium. It is most commonly caused by bacteria, although it can also be caused by fungi or viruses. IE can be classified as acute, subacute, or chronic depending on the duration of illness. Risk factors for IE include IV drug use, valvular heart disease, prosthetic valves, structural congenital heart disease, previous episodes of IE, hypertrophic cardiomyopathy, immune suppression, chronic inflammatory conditions, and poor dental hygiene.

The epidemiology of IE has changed in recent years, with Staphylococcus aureus now being the most common causative organism in most industrialized countries. Other common organisms include coagulase-negative staphylococci, streptococci, and enterococci. The distribution of causative organisms varies depending on whether the patient has a native valve, prosthetic valve, or is an IV drug user.

Clinical features of IE include fever, heart murmurs (most commonly aortic regurgitation), non-specific constitutional symptoms, petechiae, splinter hemorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots, arthritis, splenomegaly, meningism/meningitis, stroke symptoms, and pleuritic pain.

The diagnosis of IE is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Major criteria include positive blood cultures with typical microorganisms and positive echocardiogram findings. Minor criteria include fever, vascular phenomena, immunological phenomena, and microbiological phenomena. Blood culture and echocardiography are key tests for diagnosing IE.

In summary, infective endocarditis is an infection of the innermost layer of the heart that is most commonly caused by bacteria. It can be classified as acute, subacute, or chronic and can be caused by a variety of risk factors. Staphylococcus aureus is now the most common causative organism in most industrialized countries. Clinical features include fever, heart murmurs, and various other symptoms. The diagnosis is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Blood culture and echocardiography are important tests for diagnosing IE.

The effects of adrenaline on alpha-adrenergic receptors result in the narrowing of blood vessels throughout the body, leading to increased pressure in the coronary and cerebral arteries. On the other hand, the effects of adrenaline on beta-adrenergic receptors enhance the strength of the heart’s contractions and increase the heart rate, which can potentially improve blood flow to the coronary and cerebral arteries. However, it is important to note that these positive effects may be counteracted by the simultaneous increase in oxygen consumption by the heart, the occurrence of abnormal heart rhythms, reduced oxygen levels due to abnormal blood flow patterns, impaired small blood vessel function, and worsened heart function following a cardiac arrest.

Cerebral edema is the most significant complication of diabetic ketoacidosis (DKA), leading to death in many cases. It occurs in approximately 0.2-1% of DKA cases. The high blood glucose levels cause an osmolar gradient, resulting in the movement of water from the intracellular fluid (ICF) to the extracellular fluid (ECF) space and a decrease in cell volume. When insulin and intravenous fluids are administered to correct the condition, the effective osmolarity decreases rapidly, causing a reversal of the fluid shift and the development of cerebral edema.

Cerebral edema is associated with a higher mortality rate and poor neurological outcomes. To prevent its occurrence, it is important to slowly normalize osmolarity over a period of 48 hours, paying attention to glucose and sodium levels, as well as ensuring proper hydration. Monitoring the child for symptoms such as headache, recurrent vomiting, irritability, changes in Glasgow Coma Scale (GCS), abnormal slowing of heart rate, and increasing blood pressure is crucial.

If cerebral edema does occur, it should be treated with either a hypertonic (3%) saline solution at a dosage of 3 ml/kg or a mannitol infusion at a dosage of 250-500 mg/kg over a 20-minute period.

In addition to cerebral edema, there are other complications associated with DKA in children, including cardiac arrhythmias, pulmonary edema, and acute renal failure.

Bleeding in a confirmed early pregnancy, along with adnexal tenderness and cervical motion tenderness, is indicative of an ectopic pregnancy until proven otherwise. The amount of bleeding caused by an ectopic pregnancy can range from no bleeding or slight spotting to a level similar to a normal menstrual period. It is important to note that 90% of patients with an ectopic pregnancy experience abdominal pain. Other clinical features that may be present include shoulder tip pain, which is caused by irritation of the diaphragm, as well as adnexal tenderness, cervical motion tenderness, rebound tenderness, guarding, and adnexal masses in some cases. Additionally, hypotension and shock may occur.

For the treatment of men with lower urinary tract infection (UTI), it is recommended to offer an immediate prescription of antibiotics. However, certain factors should be taken into account. This includes considering previous urine culture and susceptibility results, as well as any history of antibiotic use that may have led to the development of resistant bacteria.

Before starting antibiotics, it is important to obtain a midstream urine sample from men and send it for culture and susceptibility testing. This will help determine the most appropriate choice of antibiotic.

Once the microbiological results are available, it is necessary to review the initial choice of antibiotic. If the bacteria are found to be resistant and symptoms are not improving, it is recommended to switch to a narrow-spectrum antibiotic whenever possible.

The first-choice antibiotics for men with lower UTI are trimethoprim 200 mg taken orally twice daily for 7 days, or nitrofurantoin 100 mg modified-release taken orally twice daily for 7 days if the estimated glomerular filtration rate (eGFR) is above 45 ml/minute.

If there is no improvement in lower UTI symptoms after at least 48 hours on the first-choice antibiotics, or if the first-choice is not suitable, it is important to consider alternative diagnoses and follow the recommendations in the NICE guidelines on pyelonephritis (acute): antimicrobial prescribing or prostatitis (acute): antimicrobial prescribing. The choice of antibiotic should be based on recent culture and susceptibility results.

The Act establishes five principles that aim to govern decisions made under the legislation:

1. Capacity is presumed unless proven otherwise: It is assumed that a person has the ability to make decisions unless it is proven that they lack capacity.

2. Assistance must be provided before determining incapacity: A person should not be considered unable to make a decision until all reasonable efforts have been made to support them in doing so.

3. Unwise decisions do not indicate incapacity: Making a decision that others may consider unwise does not automatically mean that a person lacks capacity.

4. Best interests must guide decision-making: All decisions made on behalf of an incapacitated person must be in their best interests.

5. Least restrictive approach should be taken: Decisions should be made in a way that minimizes any restrictions on the individual’s fundamental rights and freedoms.

If a decision significantly conflicts with these principles, it is unlikely to be lawful.

A person is deemed to lack capacity if they are unable to:

– Understand the relevant information related to the decision.
– Retain the information in their memory.
– Use or evaluate the information to make a decision.
– Communicate their decision effectively, using any means necessary.

When assessing capacity, it is important to consider the input of those close to the individual, if appropriate. Close friends and family may provide valuable insights, although their opinions should not unduly influence the assessment.

In urgent situations where a potentially life-saving decision needs to be made, an IMCA (Independent Mental Capacity Advocate) does not need to be involved.

When a person’s systolic blood pressure is less than 90 mmHg, it indicates low blood pressure. A pulse rate above 100 or below 60 beats per minute is considered abnormal. An anion gap above 16 is indicative of an imbalance in the body’s electrolytes.

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.

Patients who have suffered burns should receive high-flow oxygen (15 L) through a reservoir bag while their breathing is being evaluated. If intubation is necessary, it is crucial to use an appropriately sized endotracheal tube (ETT). Using a tube that is too small can make it difficult or even impossible to ventilate the patient, clear secretions, or perform bronchoscopy.

According to the ATLS guidelines, adults should be intubated using an ETT with an internal diameter (ID) of at least 7.5 mm or larger. Children, on the other hand, should have an ETT with an ID of at least 4.5 mm. Once a patient has been intubated, it is important to continue administering 100% oxygen until their carboxyhemoglobin levels drop to less than 5%.

To protect the lungs, it is recommended to use lung protective ventilation techniques. This involves using low tidal volumes (4-8 mL/kg) and ensuring that peak inspiratory pressures do not exceed 30 cmH2O.

Lung protective ventilation is a strategy that involves using smaller amounts of air during each breath (low tidal volumes) and restricting the maximum pressure applied during inhalation (plateau pressure). This approach also allows for a certain level of increased carbon dioxide levels in the body (hypercapnia).

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.

Alteplase (rt-pA) is recommended for the treatment of acute ischaemic stroke in adults if it is administered as soon as possible within 4.5 hours of the onset of stroke symptoms. It is important to exclude intracranial haemorrhage through appropriate imaging techniques before starting the treatment. The initial dose of alteplase is 0.9 mg/kg, with a maximum dose of 90 mg. This dose should be given intravenously over a period of 60 minutes. The first 10% of the dose should be administered through intravenous injection, while the remaining dose should be given through intravenous infusion. For a patient weighing 70 kg, the recommended dose would be 63 mg. For more information, please refer to the NICE guidelines on stroke and transient ischaemic attack in individuals over 16 years old.

This patient is experiencing a condition called right-sided abducens nerve palsy, which means that their sixth cranial nerve is paralyzed. As a result, the lateral rectus muscle, which is responsible for moving the eye outward, is also paralyzed. This means that the patient’s right eye is unable to turn outward. This can lead to a condition called convergent strabismus, where the eyes are not aligned properly, and diplopia, which is double vision. To compensate for the double vision, patients often tilt their head towards the side of the paralyzed muscle.

Extrapyramidal side effects are most commonly seen with the piperazine phenothiazines (fluphenazine, prochlorperazine, and trifluoperazine) and butyrophenones (benperidol and haloperidol). Among these, haloperidol is the most frequently implicated antipsychotic drug.

Tardive dyskinesia, which involves rhythmic and involuntary movements of the tongue, face, and jaw, typically develops after long-term treatment or high doses. It is the most severe manifestation of extrapyramidal symptoms, as it may become irreversible even after discontinuing the causative drug, and treatment options are generally ineffective.

Dystonia, characterized by abnormal movements of the face and body, is more commonly observed in children and young adults and tends to occur after only a few doses. Acute dystonia can be managed with intravenous administration of procyclidine (5 mg) or benzatropine (2 mg) as a bolus.

Akathisia refers to an unpleasant sensation of restlessness, while akinesia refers to an inability to initiate movement.

Elderly patients with dementia-related psychosis who are treated with haloperidol have an increased risk of mortality. This is believed to be due to a higher likelihood of experiencing cardiovascular events and infections such as pneumonia.