When administering adrenaline through the ET tube in pediatric cardiac arrest, the recommended dose is 100 mcg/kg. In this particular scenario, the child weighs 25 kg, so the appropriate amount to administer would be 2500 mcg (equivalent to 2.5 mg).

Heat stroke is a condition characterized by a core temperature higher than 40.6°C, accompanied by changes in mental state and varying levels of organ dysfunction. There are two forms of heat stroke: classic non-exertional heat stroke, which occurs during high environmental temperatures and typically affects elderly patients during heat waves, and exertional heat stroke, which occurs during strenuous physical exercise in hot conditions, such as endurance athletes competing in hot weather.

The typical clinical features of heat stroke include a core temperature greater than 40.6°C, extreme fatigue, headache, syncope, facial flushing, vomiting, and diarrhea. The skin is usually hot and dry, although sweating can occur in around 50% of cases of exertional heat stroke. The loss of the ability to sweat is a late and concerning sign. Hyperventilation is almost always present. Cardiovascular dysfunction, including arrhythmias, hypotension, and shock, as well as respiratory dysfunction, including acute respiratory distress syndrome (ARDS), can occur. Central nervous system dysfunction, such as seizures and coma, may also be observed. If the temperature rises above 41.5°C, multi-organ failure, coagulopathy, and rhabdomyolysis can occur.

In the management of heat stroke, benzodiazepines like diazepam can be helpful in patients with agitation and/or shivering. They help reduce excessive heat production and agitation. In severe cases, patients may require paralysis. Antipyretics like paracetamol, aspirin, and NSAIDs have no role in the treatment of heat stroke. They do not work because the hypothalamus, which regulates body temperature, is healthy but overloaded in heat stroke. Moreover, antipyretics may actually be harmful in patients who develop complications like liver, blood, and kidney problems as they can worsen bleeding tendencies.

Dantrolene is commonly used in the treatment of heat stroke, although there is currently no high-level evidence to support its use. Neuroleptics, such as chlorpromazine, which were once commonly used, should be avoided due to their potential adverse effects, including lowering the seizure threshold, interfering with thermoregulation, causing anticholinergic side effects, hypotension, and hepatotoxicity.

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

Further Reading:

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

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

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

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

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

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

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

Further Reading:

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

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

Hypothermia occurs when the core body temperature drops below 35°C. It is categorized as mild (32-35°C), moderate (28-32°C), or severe (<28°C). Rescuers at the scene can use the Swiss staging system to describe the condition of victims. The stages range from clearly conscious and shivering to unconscious and not breathing, with death due to irreversible hypothermia being the most severe stage. There are several risk factors for hypothermia, including environmental exposure, unsatisfactory housing, poverty, lack of cold awareness, drugs, alcohol, acute confusion, hypothyroidism, and sepsis. The clinical features of hypothermia vary depending on the severity. At 32-35°C, symptoms may include apathy, amnesia, ataxia, and dysarthria. At 30-32°C, there may be a decreased level of consciousness, hypotension, arrhythmias, respiratory depression, and muscular rigidity. Below 30°C, ventricular fibrillation may occur, especially with excessive movement or invasive procedures. Diagnosing hypothermia involves checking the core temperature using an oesophageal, rectal, or tympanic probe with a low reading thermometer. Rectal and tympanic temperatures may lag behind core temperature and are unreliable in hypothermia. Various investigations should be carried out, including blood tests, blood glucose, amylase, blood cultures, arterial blood gas, ECG, chest X-ray, and CT head if there is suspicion of head injury or CVA. The management of hypothermia involves supporting the ABCs, treating the patient in a warm room, removing wet clothes and drying the skin, monitoring the ECG, providing warmed, humidified oxygen, correcting hypoglycemia with IV glucose, and handling the patient gently to avoid VF arrest. Re-warming methods include passive re-warming with warm blankets or Bair hugger/polythene sheets, surface re-warming with a water bath, core re-warming with heated, humidified oxygen or peritoneal lavage, and extracorporeal re-warming via cardiopulmonary bypass for severe hypothermia/cardiac arrest. In the case of hypothermic cardiac arrest, CPR should be performed with chest compressions and ventilations at standard rates.

Thought blocking is a distressing phenomenon where one’s train of thought is abruptly halted. This occurrence is observed in various psychiatric disorders, such as schizophrenia. It manifests as sudden pauses in a person’s speech, lasting from a few seconds to even a minute or more.

During the first trimester of pregnancy, the use of trimethoprim is linked to an increased risk of neural tube defects because it antagonizes folate. If it is not possible to use an alternative antibiotic, it is recommended that pregnant women taking trimethoprim also take high-dose folic acid. However, the use of trimethoprim in the second and third trimesters of pregnancy is considered safe.

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

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

Aminoglycosides (e.g. gentamicin): They can cause ototoxicity and deafness.

Aspirin: High doses 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 significant risks.

Benzodiazepines (e.g. diazepam): When given late in pregnancy, they can cause respiratory depression and a neonatal withdrawal syndrome.

Calcium-channel blockers: If given in the first trimester, they can cause phalangeal abnormalities. If given in the second and third trimesters, they can lead to fetal growth retardation.

Carbamazepine: It can cause hemorrhagic disease of the newborn and neural tube defects.

Chloramphenicol: It can cause grey baby syndrome.

Corticosteroids: If given in the first trimester, they may cause orofacial clefts.

Danazol: If given in the first trimester, it can cause masculinization of the female fetuses genitals.

Finasteride: Pregnant women should avoid handling finasteride as crushed or broken tablets can be absorbed through the skin and affect male sex organ development.

Haloperidol: If given in the first trimester, it may cause limb malformations. If given in the third trimester, there is an increased risk of extrapyramidal symptoms in the neonate.

Heparin: It can cause maternal bleeding and thrombocytopenia.

Isoniazid: It can lead to maternal liver damage and neuropathy and seizures in the neonate.

Theophylline is a medication used to treat severe asthma. It is a bronchodilator that comes in modified-release forms, which can maintain therapeutic levels in the blood for 12 hours. Theophylline works by inhibiting phosphodiesterase and blocking the breakdown of cyclic AMP. It also competes with adenosine on A1 and A2 receptors.

Achieving the right dose of theophylline can be challenging because there is a narrow range between therapeutic and toxic levels. The half-life of theophylline can be influenced by various factors, further complicating dosage adjustments. It is recommended to aim for serum levels of 10-20 mg/l six to eight hours after the last dose.

Unlike many other medications, the specific brand of theophylline can significantly impact its effects. Therefore, it is important to prescribe theophylline by both its brand name and generic name.

Several factors can increase the half-life of theophylline, including heart failure, cirrhosis, viral infections, and certain drugs. Conversely, smoking, heavy drinking, and certain medications can decrease the half-life of theophylline.

There are several drugs that can either increase or decrease the plasma concentration of theophylline. Calcium channel blockers, cimetidine, fluconazole, macrolides, methotrexate, and quinolones can increase the concentration. On the other hand, carbamazepine, phenobarbitol, phenytoin, rifampicin, and St. John’s wort can decrease the concentration.

The clinical symptoms of theophylline toxicity are more closely associated with acute overdose rather than chronic overexposure. Common symptoms include headache, dizziness, nausea, vomiting, abdominal pain, rapid heartbeat, dysrhythmias, seizures, mild metabolic acidosis, low potassium, low magnesium, low phosphates, abnormal calcium levels, and high blood sugar.

Seizures are more prevalent in acute overdose cases, while chronic overdose typically presents with minimal gastrointestinal symptoms. Cardiac dysrhythmias are more common in chronic overdose situations compared to acute overdose.

The NICE guidelines for suspected deep vein thrombosis (DVT) suggest considering the possibility of DVT if typical symptoms and signs are present, particularly if the person has risk factors like previous venous thromboembolism and immobility.

Typical signs and symptoms of DVT include unilateral localized pain (often throbbing) that occurs during walking or bearing weight, as well as calf swelling (or, less commonly, swelling of the entire leg). Other signs to look out for are tenderness, skin changes such as edema, redness, and warmth, and vein distension.

To rule out other potential causes for the symptoms and signs, it is important to conduct a physical examination and review the person’s general medical history.

When assessing leg and thigh swelling, it is recommended to measure the circumference of the leg 10 cm below the tibial tuberosity and compare it with the unaffected leg. A difference of more than 3 cm between the two legs increases the likelihood of DVT.

Additionally, it is important to check for edema and dilated collateral superficial veins on the affected side.

To assess the likelihood of DVT and guide further management, the two-level DVT Wells score can be used.

For more information, you can refer to the NICE Clinical Knowledge Summary on deep vein thrombosis.

Status epilepticus is a condition characterized by continuous seizure activity lasting for 5 minutes or more without the return of consciousness, or recurrent seizures (2 or more) without a period of neurological recovery in between. In such cases, the next step in managing the patient would be to administer a second dose of benzodiazepine. Since the patient already has an intravenous line in place, this would be the most appropriate route to choose.

The management of status epilepticus involves several general measures, which are outlined in the following table:

1st stage (Early status, 0-10 minutes):
– Secure the airway and provide resuscitation
– Administer oxygen
– Assess cardiorespiratory function
– Establish intravenous access

2nd stage (0-30 minutes):
– Institute regular monitoring
– Consider the possibility of non-epileptic status
– Start emergency antiepileptic drug (AED) therapy
– Perform emergency investigations
– Administer glucose (50 ml of 50% solution) and/or intravenous thiamine as Pabrinex if there is any suggestion of alcohol abuse or impaired nutrition
– Treat severe acidosis if present

3rd stage (0-60 minutes):
– Determine the underlying cause of status epilepticus
– Alert the anaesthetist and intensive care unit (ITU)
– Identify and treat any medical complications
– Consider pressor therapy when appropriate

4th stage (30-90 minutes):
– Transfer the patient to the intensive care unit
– Establish intensive care and EEG monitoring
– Initiate intracranial pressure monitoring if necessary
– Start initial long-term, maintenance AED therapy

Emergency investigations for status epilepticus include blood tests for gases, glucose, renal and liver function, calcium and magnesium, full blood count (including platelets), blood clotting, and AED drug levels. Serum and urine samples should be saved for future analysis, including toxicology if the cause of the convulsive status epilepticus is uncertain. A chest radiograph may be performed to evaluate the possibility of aspiration. Additional investigations, such as brain imaging or lumbar puncture, depend on the clinical circumstances.

Monitoring during the management of status epilepticus involves regular neurological observations and measurements of pulse, blood pressure, and temperature. ECG, biochemistry, blood gases, clotting, and blood count should also be monitored.