Arab Board EM Final Written cheat sheet

Cardiac arrest with shockable rhythm (VF/pVT): unsynchronised biphasic shock 150-200 J, then immediate CPR 2 min before rhythm recheck.

Non-shockable arrest (asystole/PEA): adrenaline 1 mg IV every 3-5 min; shockable arrest gives adrenaline only after the third shock.

Reversible causes mnemonic 4H/4T: hypoxia, hypovolaemia, hypo/hyperkalaemia-metabolic, hypothermia; tension pneumothorax, tamponade, toxins, thrombosis.

STEMI reperfusion: primary PCI within 120 min of first medical contact is preferred; fibrinolysis if PCI unavailable within 120 min and symptom onset <12 h without contraindication.

Acute decompensated heart failure: IV loop diuretic plus non-invasive ventilation for pulmonary oedema; nitrates contraindicated in hypotension or right ventricular infarction.

Unstable tachycardia with a pulse and adverse features (hypotension, ischaemia, heart failure, shock) requires synchronised cardioversion; stable narrow-complex SVT: vagal manoeuvres then adenosine 6 mg IV.

Aortic dissection: painless pulse/BP differential, widened mediastinum; give rate-control (target HR 60) before vasodilator to limit shear stress.

Post-ROSC care: target SpO2 94-98%, normocapnia, MAP >=65 mmHg, 12-lead ECG and coronary angiography for STEMI; targeted temperature management 32-36 C for comatose survivors.

Asthma severity: inability to complete sentences, silent chest, SpO2 <92%, peak flow <33% predicted, exhaustion or altered consciousness indicate life-threatening attack.

Acute severe asthma: oxygen to SpO2 94-98%, salbutamol and ipratropium nebulised, systemic corticosteroid within 1 h, and IV magnesium sulfate for poor response.

Tension pneumothorax is a clinical diagnosis: immediate needle decompression (2nd intercostal space midclavicular or 4th-5th anterior axillary) followed by chest drain; never wait for imaging.

Massive pulmonary embolism: hypotension plus RV strain; treat with systemic thrombolysis or catheter-directed therapy, and avoid aggressive fluid boluses.

Wells score and PERC aid PE pretest probability; D-dimer is used to rule out PE in low/intermediate probability patients only.

COPD exacerbation: controlled oxygen targeting SpO2 88-92% in at-risk patients, short-acting bronchodilators, systemic steroids, and non-invasive ventilation for pH 7.25-7.35 with hypercapnia.

Pneumonia severity: CURB-65 (confusion, urea >7 mmol/L, respiratory rate >=30, BP low, age >=65) with score >=2 suggesting admission and >=3 severe.

High-flow nasal oxygen delivers heated humidified gas up to 60 L/min with FiO2 up to 1.0; it provides modest PEEP and reduces work of breathing.

Acute ischaemic stroke: IV thrombolysis within 4.5 h of onset; mechanical thrombectomy up to 24 h in selected large-vessel occlusion with favourable imaging.

Stroke thrombolysis exclusions include BP >185/110 mmHg unresponsive to treatment, recent intracranial surgery, active bleeding, and anticoagulation with INR >1.7.

Subarachnoid haemorrhage: CT sensitivity highest within 6 h; if CT negative and suspicion persists after 6 h, perform lumbar puncture for xanthochromia.

Status epilepticus: benzodiazepine first line (IV lorazepam or IM midazolam), then second-line IV levetiracetam, valproate, or phenytoin; refractory cases need anaesthetic agents.

Bacterial meningitis: dexamethasone before or with first antibiotic dose in suspected pneumococcal disease; do not delay antibiotics for lumbar puncture in unstable patients.

Glasgow Coma Scale scores 3-15 by summing eye (1-4), verbal (1-5) and motor (1-6); GCS <=8 generally indicates need for airway protection.

Acute dystonia from dopamine antagonists is treated with IV anticholinergics (benztropine or procyclidine); neuroleptic malignant syndrome features rigidity, hyperthermia and raised CK.

Headache red flags: thunderclap onset, fever with neck stiffness, focal deficit, papilloedema, age >50 with new headache, and headache worsened by Valsalva.

Upper GI bleed: resuscitate before endoscopy; give IV proton-pump inhibitor for suspected non-variceal bleed and vasoactive drug plus prophylactic antibiotics for suspected variceal bleed.

Glasgow-Blatchford score <=1 identifies very low-risk upper GI bleed suitable for outpatient management.

Spontaneous bacterial peritonitis: diagnostic ascitic neutrophil count >=250/mm3; treat with third-generation cephalosporin and give albumin in renal impairment.

Acute liver failure: coagulopathy (INR >=1.5) plus encephalopathy in a patient without cirrhosis; give N-acetylcysteine and consider transplant referral.

Hyperkalaemia with ECG changes: IV calcium gluconate for membrane stabilisation, insulin-dextrose and salbutamol to shift potassium, then dialysis or binders for removal.

Acute kidney injury staged by KDIGO using creatinine rise and urine output; urgent dialysis indications include refractory hyperkalaemia, acidosis, pulmonary oedema, and uraemic complications.

Acute pancreatitis diagnosis requires two of: characteristic pain, lipase/amylase >3x upper limit, and imaging findings; early aggressive fluid resuscitation is key.

Mesenteric ischaemia: pain out of proportion to examination, lactate may be normal early; CT angiography is diagnostic and early surgical review is essential.

ATLS primary survey sequence: catastrophic haemorrhage control, airway with cervical spine protection, breathing, circulation, disability, exposure.

Haemorrhagic shock: permissive hypotension (systolic ~90 mmHg) until surgical control in penetrating trauma without head injury; tranexamic acid within 3 h of injury.

Massive transfusion protocols use balanced ratios approaching 1:1:1 of red cells, plasma, and platelets, with calcium replacement to avoid citrate hypocalcaemia.

Tension pneumothorax and cardiac tamponade are the immediately lethal thoracic injuries; Beck triad (hypotension, distended neck veins, muffled heart sounds) is insensitive.

Open fracture: antibiotics within 1 h, tetanus prophylaxis, and urgent surgical debridement; do not delay for imaging.

Compartment syndrome: pain out of proportion, pain on passive stretch, tense compartment; pulselessness is a late sign and absence of pulse is not required for diagnosis.

Pelvic fracture with haemodynamic instability: apply pelvic binder at the level of the greater trochanters and consider angioembolisation or preperitoneal packing.

Neurovascular compromise or open fracture with vascular injury requires urgent orthopaedic and vascular consultation; document distal pulses and sensation before and after reduction.

Paracetamol overdose: N-acetylcysteine based on Rumack-Matthew nomogram from 4 h post-ingestion; if timing unknown or staggered, start NAC empirically.

Salicylate toxicity: mixed respiratory alkalosis and metabolic acidosis, tinnitus, and hypokalaemia; urinary alkalinisation with sodium bicarbonate enhances elimination.

Tricyclic antidepressant toxicity: sodium-channel blockade causing QRS >100 ms; give sodium bicarbonate boluses and avoid class IA/IC antiarrhythmics.

Beta-blocker overdose: glucagon, high-dose insulin-euglycaemia, and calcium salts; atropine for bradycardia is often ineffective.

Calcium channel blocker overdose: IV calcium, high-dose insulin, vasopressors, and lipid emulsion in refractory cases.

Opioid overdose: titrate naloxone to respiratory rate; beware precipitating acute withdrawal and the need for repeat dosing due to shorter half-life than many opioids.

Toxic alcohol (methanol/ethylene glycol): osmolar gap, metabolic acidosis; treat with fomepizole or ethanol and consider haemodialysis.

Carbon monoxide poisoning: measure carboxyhaemoglobin; 100% oxygen for all, hyperbaric oxygen for severe poisoning, syncope, or pregnancy.

Heat stroke: core temperature >40 C with CNS dysfunction; rapid cooling (evaporative or cold-water immersion) and IV fluids are priorities.

Hypothermia: use low-reading thermometer; rewarm, and note that severe hypothermia can cause refractory arrest where prolonged resuscitation may be appropriate.

Diabetic ketoacidosis: fluids first, insulin infusion after potassium >=3.3 mmol/L, and add dextrose when glucose falls; total body potassium is depleted despite normal serum values.

Hyperosmolar hyperglycaemic state: profound dehydration and hyperosmolality with minimal ketosis; fluid replacement is the cornerstone.

Severe hyponatraemia with seizures: hypertonic 3% saline boluses to raise sodium by 4-6 mmol/L acutely; avoid correction >10 mmol/L in 24 h to prevent osmotic demyelination.

High-altitude illness: descent is definitive; dexamethasone for cerebral oedema, nifedipine for pulmonary oedema, and acetazolamide for prevention.

Drowning: hypoxia is the primary insult; rescue breathing and CPR are priorities, and routine abdominal thrusts or spinal immobilisation are not indicated.

Adrenal crisis: hypotension refractory to fluids and catecholamines; give IV hydrocortisone immediately when suspected.

Paediatric assessment triangle: appearance, work of breathing, and circulation to skin; used before hands-on assessment.

Paediatric cardiac arrest is usually hypoxic; give oxygen and ventilations early, and use 4 J/kg for defibrillation (up to 10 J/kg).

Weight-based dosing: use length-based tape or age-based formula (weight kg = 2 x age + 8) for children 1-10 years.

Croup: barking cough and stridor; treat with dexamethasone and nebulised adrenaline for moderate-severe cases.

Bronchiolitis: supportive care with oxygen and hydration; routine bronchodilators, steroids, and antibiotics are not recommended.

Kawasaki disease: fever >=5 days plus mucocutaneous features; treat with IV immunoglobulin and aspirin to prevent coronary artery aneurysms.

Paediatric sepsis: tachycardia and tachypnoea may be the earliest signs; hypotension is a late finding; give early antibiotics and fluid boluses of 10-20 mL/kg.

Non-accidental injury red flags: injury inconsistent with development, delayed presentation, and patterned or metaphyseal injuries; follow safeguarding pathways.

Ectopic pregnancy: any woman of reproductive age with abdominal pain, amenorrhoea, or syncope should have a pregnancy test; unstable patients need urgent surgical management.

Ovarian torsion: sudden unilateral pain with nausea; do not delay surgical detorsion for imaging if suspicion is high.

Pre-eclampsia: hypertension after 20 weeks with proteinuria or end-organ dysfunction; severe features include BP >=160/110, platelets <100, and transaminitis.

Eclampsia: magnesium sulfate is the drug of choice for seizure control and prophylaxis; monitor reflexes, respiratory rate, and urine output.

Postpartum haemorrhage: uterine atony is the commonest cause; treat with uterine massage, oxytocin, then ergometrine, carboprost, or misoprostol, and tranexamic acid.

HELLP syndrome: haemolysis, elevated liver enzymes, low platelets; delivery is definitive treatment.

Placental abruption: painful vaginal bleeding with uterine tenderness and fetal distress; concealed haemorrhage may underestimate blood loss.

Physiological changes in pregnancy include increased plasma volume, dilutional anaemia, and aortocaval compression after 20 weeks requiring left lateral tilt during resuscitation.

Sepsis is life-threatening organ dysfunction from infection; septic shock is sepsis with vasopressor requirement and lactate >2 mmol/L despite fluid resuscitation.

Sepsis bundle: measure lactate, obtain blood cultures before antibiotics, give broad-spectrum antibiotics within 1 h for septic shock, and give 30 mL/kg crystalloid for hypotension or lactate >=4.

Neutropenic sepsis: fever >=38 C with neutrophils <0.5 x 10^9/L requires immediate empirical antipseudomonal beta-lactam antibiotics.

Meningococcal sepsis: petechial rash and rapid deterioration; treat with IV ceftriaxone and consider droplet precautions and chemoprophylaxis for contacts.

Necrotising fasciitis: pain out of proportion, bullae, crepitus, and systemic toxicity; urgent surgical debridement plus broad-spectrum antibiotics including clindamycin.

Tetanus and rabies are prevented by vaccination; rabies post-exposure prophylaxis includes wound washing, vaccine, and immunoglobulin for category III exposures.

Tuberculosis: airborne precautions with negative-pressure room and N95 respirator for suspected pulmonary TB.

Antimicrobial stewardship: de-escalate based on culture results, document indication and duration, and review at 48-72 h.

FAST exam views: subxiphoid cardiac, right upper quadrant (Morison pouch), left upper quadrant (splenorenal), and pelvic views; free fluid appears anechoic.

FAST detects free fluid, not solid organ injury; a negative FAST does not exclude injury and should be repeated or followed by CT in stable patients.

Focused echo in arrest: identify cardiac standstill, tamponade, and right ventricular dilation suggesting massive PE.

Aortic ultrasound: measure outer-to-outer wall diameter; >3 cm is aneurysmal and >5 cm or symptomatic warrants urgent surgical consultation.

First-trimester ultrasound: intrauterine gestational sac seen at ~5 weeks; absence of intrauterine pregnancy with positive beta-hCG raises ectopic concern.

Lung ultrasound: B-lines suggest interstitial oedema; absence of lung sliding suggests pneumothorax; consolidation with air bronchograms supports pneumonia.

Ocular ultrasound: optic nerve sheath diameter >5 mm suggests raised intracranial pressure; retinal detachment appears as a mobile membrane.

Ultrasound-guided procedures improve first-pass success and reduce complications for central venous access, nerve blocks, and drainage.

Difficult airway prediction: Mallampati class, thyromental distance <3 fingerbreadths, mouth opening <3 cm, limited neck extension, and obesity.

Rapid sequence intubation: preoxygenation, pretreat selected patients, induction agent, neuromuscular blocker, and immediate intubation with cricoid pressure if indicated.

Failed airway algorithm: optimise laryngoscopy, use supraglottic airway, and proceed to surgical airway if cannot intubate and cannot oxygenate.

Succinylcholine is contraindicated in hyperkalaemia, burns or crush injury beyond 24-48 h, and known pseudocholinesterase deficiency.

Post-intubation care: confirm with waveform capnography, secure tube, set ventilator, and provide sedation and analgesia.

Central venous access: internal jugular preferred in most emergencies; use ultrasound and confirm tip position with chest radiograph or manometry.

Thoracostomy: insert in the safe triangle (5th intercostal space, mid-axillary line); avoid the nipple line and inferior intercostal neurovascular bundle.

Defibrillation safety: ensure no one touches the patient, use correct pad placement, and resume compressions immediately after shock.

Triage systems such as the Emergency Severity Index assign acuity from 1 (immediate) to 5 (non-urgent) based on resource needs and vital signs.

Crowding metrics include ED occupancy, boarding time, and left-without-being-seen rates; boarding of admitted patients is a major driver of crowding.

Disaster triage uses colour codes: red immediate, yellow delayed, green minor, black deceased or expectant.

START triage: assess respiration, perfusion, and mental status in under 60 seconds per patient.

Incident command system uses a single incident commander with sections for operations, planning, logistics, and finance/administration.

Handover standardisation with SBAR (situation, background, assessment, recommendation) reduces communication errors.

Root cause analysis is a structured retrospective method for serious safety events; failure mode and effects analysis is prospective.

Personal protective equipment and decontamination zones (hot, warm, cold) are essential in hazardous material incidents.

Sensitivity = true positives / (true positives + false negatives); specificity = true negatives / (true negatives + false positives).

Positive predictive value depends on prevalence; likelihood ratio positive = sensitivity / (1 - specificity) and is prevalence-independent.

Number needed to treat = 1 / absolute risk reduction; relative risk reduction can overstate benefit when baseline risk is low.

Levels of evidence: systematic reviews and randomised trials rank above cohort and case-control studies; case reports are lowest.

Randomised controlled trials reduce confounding by randomisation but may be limited by lack of blinding and intention-to-treat analysis issues.

Informed consent requires capacity, disclosure, understanding, and voluntariness; emergency exception applies when immediate treatment is life-saving and no proxy is available.

Confidentiality may be breached when required by law or when there is serious risk to the patient or others.

Publication bias and conflicts of interest threaten validity; check trial registration and funding in critical appraisal.

Cardiac arrest with shockable rhythm (VF/pVT): unsynchronised biphasic shock 150-200 J, then immediate CPR 2 min before rhythm recheck.

Non-shockable arrest (asystole/PEA): adrenaline 1 mg IV every 3-5 min; shockable arrest gives adrenaline only after the third shock.

Reversible causes mnemonic 4H/4T: hypoxia, hypovolaemia, hypo/hyperkalaemia-metabolic, hypothermia; tension pneumothorax, tamponade, toxins, thrombosis.

STEMI reperfusion: primary PCI within 120 min of first medical contact is preferred; fibrinolysis if PCI unavailable within 120 min and symptom onset <12 h without contraindication.

Acute decompensated heart failure: IV loop diuretic plus non-invasive ventilation for pulmonary oedema; nitrates contraindicated in hypotension or right ventricular infarction.

Unstable tachycardia with a pulse and adverse features (hypotension, ischaemia, heart failure, shock) requires synchronised cardioversion; stable narrow-complex SVT: vagal manoeuvres then adenosine 6 mg IV.

Aortic dissection: painless pulse/BP differential, widened mediastinum; give rate-control (target HR 60) before vasodilator to limit shear stress.

Post-ROSC care: target SpO2 94-98%, normocapnia, MAP >=65 mmHg, 12-lead ECG and coronary angiography for STEMI; targeted temperature management 32-36 C for comatose survivors.

Asthma severity: inability to complete sentences, silent chest, SpO2 <92%, peak flow <33% predicted, exhaustion or altered consciousness indicate life-threatening attack.

Acute severe asthma: oxygen to SpO2 94-98%, salbutamol and ipratropium nebulised, systemic corticosteroid within 1 h, and IV magnesium sulfate for poor response.

Tension pneumothorax is a clinical diagnosis: immediate needle decompression (2nd intercostal space midclavicular or 4th-5th anterior axillary) followed by chest drain; never wait for imaging.

Massive pulmonary embolism: hypotension plus RV strain; treat with systemic thrombolysis or catheter-directed therapy, and avoid aggressive fluid boluses.

Wells score and PERC aid PE pretest probability; D-dimer is used to rule out PE in low/intermediate probability patients only.

COPD exacerbation: controlled oxygen targeting SpO2 88-92% in at-risk patients, short-acting bronchodilators, systemic steroids, and non-invasive ventilation for pH 7.25-7.35 with hypercapnia.

Pneumonia severity: CURB-65 (confusion, urea >7 mmol/L, respiratory rate >=30, BP low, age >=65) with score >=2 suggesting admission and >=3 severe.

High-flow nasal oxygen delivers heated humidified gas up to 60 L/min with FiO2 up to 1.0; it provides modest PEEP and reduces work of breathing.

Acute ischaemic stroke: IV thrombolysis within 4.5 h of onset; mechanical thrombectomy up to 24 h in selected large-vessel occlusion with favourable imaging.

Stroke thrombolysis exclusions include BP >185/110 mmHg unresponsive to treatment, recent intracranial surgery, active bleeding, and anticoagulation with INR >1.7.

Subarachnoid haemorrhage: CT sensitivity highest within 6 h; if CT negative and suspicion persists after 6 h, perform lumbar puncture for xanthochromia.

Status epilepticus: benzodiazepine first line (IV lorazepam or IM midazolam), then second-line IV levetiracetam, valproate, or phenytoin; refractory cases need anaesthetic agents.

Bacterial meningitis: dexamethasone before or with first antibiotic dose in suspected pneumococcal disease; do not delay antibiotics for lumbar puncture in unstable patients.

Glasgow Coma Scale scores 3-15 by summing eye (1-4), verbal (1-5) and motor (1-6); GCS <=8 generally indicates need for airway protection.

Acute dystonia from dopamine antagonists is treated with IV anticholinergics (benztropine or procyclidine); neuroleptic malignant syndrome features rigidity, hyperthermia and raised CK.

Headache red flags: thunderclap onset, fever with neck stiffness, focal deficit, papilloedema, age >50 with new headache, and headache worsened by Valsalva.

Upper GI bleed: resuscitate before endoscopy; give IV proton-pump inhibitor for suspected non-variceal bleed and vasoactive drug plus prophylactic antibiotics for suspected variceal bleed.

Glasgow-Blatchford score <=1 identifies very low-risk upper GI bleed suitable for outpatient management.

Spontaneous bacterial peritonitis: diagnostic ascitic neutrophil count >=250/mm3; treat with third-generation cephalosporin and give albumin in renal impairment.

Acute liver failure: coagulopathy (INR >=1.5) plus encephalopathy in a patient without cirrhosis; give N-acetylcysteine and consider transplant referral.

Hyperkalaemia with ECG changes: IV calcium gluconate for membrane stabilisation, insulin-dextrose and salbutamol to shift potassium, then dialysis or binders for removal.

Acute kidney injury staged by KDIGO using creatinine rise and urine output; urgent dialysis indications include refractory hyperkalaemia, acidosis, pulmonary oedema, and uraemic complications.

Acute pancreatitis diagnosis requires two of: characteristic pain, lipase/amylase >3x upper limit, and imaging findings; early aggressive fluid resuscitation is key.

Mesenteric ischaemia: pain out of proportion to examination, lactate may be normal early; CT angiography is diagnostic and early surgical review is essential.

ATLS primary survey sequence: catastrophic haemorrhage control, airway with cervical spine protection, breathing, circulation, disability, exposure.

Haemorrhagic shock: permissive hypotension (systolic ~90 mmHg) until surgical control in penetrating trauma without head injury; tranexamic acid within 3 h of injury.

Massive transfusion protocols use balanced ratios approaching 1:1:1 of red cells, plasma, and platelets, with calcium replacement to avoid citrate hypocalcaemia.

Tension pneumothorax and cardiac tamponade are the immediately lethal thoracic injuries; Beck triad (hypotension, distended neck veins, muffled heart sounds) is insensitive.

Open fracture: antibiotics within 1 h, tetanus prophylaxis, and urgent surgical debridement; do not delay for imaging.

Compartment syndrome: pain out of proportion, pain on passive stretch, tense compartment; pulselessness is a late sign and absence of pulse is not required for diagnosis.

Pelvic fracture with haemodynamic instability: apply pelvic binder at the level of the greater trochanters and consider angioembolisation or preperitoneal packing.

Neurovascular compromise or open fracture with vascular injury requires urgent orthopaedic and vascular consultation; document distal pulses and sensation before and after reduction.

Paracetamol overdose: N-acetylcysteine based on Rumack-Matthew nomogram from 4 h post-ingestion; if timing unknown or staggered, start NAC empirically.

Salicylate toxicity: mixed respiratory alkalosis and metabolic acidosis, tinnitus, and hypokalaemia; urinary alkalinisation with sodium bicarbonate enhances elimination.

Tricyclic antidepressant toxicity: sodium-channel blockade causing QRS >100 ms; give sodium bicarbonate boluses and avoid class IA/IC antiarrhythmics.

Beta-blocker overdose: glucagon, high-dose insulin-euglycaemia, and calcium salts; atropine for bradycardia is often ineffective.

Calcium channel blocker overdose: IV calcium, high-dose insulin, vasopressors, and lipid emulsion in refractory cases.

Opioid overdose: titrate naloxone to respiratory rate; beware precipitating acute withdrawal and the need for repeat dosing due to shorter half-life than many opioids.

Toxic alcohol (methanol/ethylene glycol): osmolar gap, metabolic acidosis; treat with fomepizole or ethanol and consider haemodialysis.

Carbon monoxide poisoning: measure carboxyhaemoglobin; 100% oxygen for all, hyperbaric oxygen for severe poisoning, syncope, or pregnancy.

Heat stroke: core temperature >40 C with CNS dysfunction; rapid cooling (evaporative or cold-water immersion) and IV fluids are priorities.

Hypothermia: use low-reading thermometer; rewarm, and note that severe hypothermia can cause refractory arrest where prolonged resuscitation may be appropriate.

Diabetic ketoacidosis: fluids first, insulin infusion after potassium >=3.3 mmol/L, and add dextrose when glucose falls; total body potassium is depleted despite normal serum values.

Hyperosmolar hyperglycaemic state: profound dehydration and hyperosmolality with minimal ketosis; fluid replacement is the cornerstone.

Severe hyponatraemia with seizures: hypertonic 3% saline boluses to raise sodium by 4-6 mmol/L acutely; avoid correction >10 mmol/L in 24 h to prevent osmotic demyelination.

High-altitude illness: descent is definitive; dexamethasone for cerebral oedema, nifedipine for pulmonary oedema, and acetazolamide for prevention.

Drowning: hypoxia is the primary insult; rescue breathing and CPR are priorities, and routine abdominal thrusts or spinal immobilisation are not indicated.

Adrenal crisis: hypotension refractory to fluids and catecholamines; give IV hydrocortisone immediately when suspected.

Paediatric assessment triangle: appearance, work of breathing, and circulation to skin; used before hands-on assessment.

Paediatric cardiac arrest is usually hypoxic; give oxygen and ventilations early, and use 4 J/kg for defibrillation (up to 10 J/kg).

Weight-based dosing: use length-based tape or age-based formula (weight kg = 2 x age + 8) for children 1-10 years.

Croup: barking cough and stridor; treat with dexamethasone and nebulised adrenaline for moderate-severe cases.

Bronchiolitis: supportive care with oxygen and hydration; routine bronchodilators, steroids, and antibiotics are not recommended.

Kawasaki disease: fever >=5 days plus mucocutaneous features; treat with IV immunoglobulin and aspirin to prevent coronary artery aneurysms.

Paediatric sepsis: tachycardia and tachypnoea may be the earliest signs; hypotension is a late finding; give early antibiotics and fluid boluses of 10-20 mL/kg.

Non-accidental injury red flags: injury inconsistent with development, delayed presentation, and patterned or metaphyseal injuries; follow safeguarding pathways.

Ectopic pregnancy: any woman of reproductive age with abdominal pain, amenorrhoea, or syncope should have a pregnancy test; unstable patients need urgent surgical management.

Ovarian torsion: sudden unilateral pain with nausea; do not delay surgical detorsion for imaging if suspicion is high.

Pre-eclampsia: hypertension after 20 weeks with proteinuria or end-organ dysfunction; severe features include BP >=160/110, platelets <100, and transaminitis.

Eclampsia: magnesium sulfate is the drug of choice for seizure control and prophylaxis; monitor reflexes, respiratory rate, and urine output.

Postpartum haemorrhage: uterine atony is the commonest cause; treat with uterine massage, oxytocin, then ergometrine, carboprost, or misoprostol, and tranexamic acid.

HELLP syndrome: haemolysis, elevated liver enzymes, low platelets; delivery is definitive treatment.

Placental abruption: painful vaginal bleeding with uterine tenderness and fetal distress; concealed haemorrhage may underestimate blood loss.

Physiological changes in pregnancy include increased plasma volume, dilutional anaemia, and aortocaval compression after 20 weeks requiring left lateral tilt during resuscitation.

Sepsis is life-threatening organ dysfunction from infection; septic shock is sepsis with vasopressor requirement and lactate >2 mmol/L despite fluid resuscitation.

Sepsis bundle: measure lactate, obtain blood cultures before antibiotics, give broad-spectrum antibiotics within 1 h for septic shock, and give 30 mL/kg crystalloid for hypotension or lactate >=4.

Neutropenic sepsis: fever >=38 C with neutrophils <0.5 x 10^9/L requires immediate empirical antipseudomonal beta-lactam antibiotics.

Meningococcal sepsis: petechial rash and rapid deterioration; treat with IV ceftriaxone and consider droplet precautions and chemoprophylaxis for contacts.

Necrotising fasciitis: pain out of proportion, bullae, crepitus, and systemic toxicity; urgent surgical debridement plus broad-spectrum antibiotics including clindamycin.

Tetanus and rabies are prevented by vaccination; rabies post-exposure prophylaxis includes wound washing, vaccine, and immunoglobulin for category III exposures.

Tuberculosis: airborne precautions with negative-pressure room and N95 respirator for suspected pulmonary TB.

Antimicrobial stewardship: de-escalate based on culture results, document indication and duration, and review at 48-72 h.

FAST exam views: subxiphoid cardiac, right upper quadrant (Morison pouch), left upper quadrant (splenorenal), and pelvic views; free fluid appears anechoic.

FAST detects free fluid, not solid organ injury; a negative FAST does not exclude injury and should be repeated or followed by CT in stable patients.

Focused echo in arrest: identify cardiac standstill, tamponade, and right ventricular dilation suggesting massive PE.

Aortic ultrasound: measure outer-to-outer wall diameter; >3 cm is aneurysmal and >5 cm or symptomatic warrants urgent surgical consultation.

First-trimester ultrasound: intrauterine gestational sac seen at ~5 weeks; absence of intrauterine pregnancy with positive beta-hCG raises ectopic concern.

Lung ultrasound: B-lines suggest interstitial oedema; absence of lung sliding suggests pneumothorax; consolidation with air bronchograms supports pneumonia.

Ocular ultrasound: optic nerve sheath diameter >5 mm suggests raised intracranial pressure; retinal detachment appears as a mobile membrane.

Ultrasound-guided procedures improve first-pass success and reduce complications for central venous access, nerve blocks, and drainage.

Difficult airway prediction: Mallampati class, thyromental distance <3 fingerbreadths, mouth opening <3 cm, limited neck extension, and obesity.

Rapid sequence intubation: preoxygenation, pretreat selected patients, induction agent, neuromuscular blocker, and immediate intubation with cricoid pressure if indicated.

Failed airway algorithm: optimise laryngoscopy, use supraglottic airway, and proceed to surgical airway if cannot intubate and cannot oxygenate.

Succinylcholine is contraindicated in hyperkalaemia, burns or crush injury beyond 24-48 h, and known pseudocholinesterase deficiency.

Post-intubation care: confirm with waveform capnography, secure tube, set ventilator, and provide sedation and analgesia.

Central venous access: internal jugular preferred in most emergencies; use ultrasound and confirm tip position with chest radiograph or manometry.

Thoracostomy: insert in the safe triangle (5th intercostal space, mid-axillary line); avoid the nipple line and inferior intercostal neurovascular bundle.

Defibrillation safety: ensure no one touches the patient, use correct pad placement, and resume compressions immediately after shock.

Triage systems such as the Emergency Severity Index assign acuity from 1 (immediate) to 5 (non-urgent) based on resource needs and vital signs.

Crowding metrics include ED occupancy, boarding time, and left-without-being-seen rates; boarding of admitted patients is a major driver of crowding.

Disaster triage uses colour codes: red immediate, yellow delayed, green minor, black deceased or expectant.

START triage: assess respiration, perfusion, and mental status in under 60 seconds per patient.

Incident command system uses a single incident commander with sections for operations, planning, logistics, and finance/administration.

Handover standardisation with SBAR (situation, background, assessment, recommendation) reduces communication errors.

Root cause analysis is a structured retrospective method for serious safety events; failure mode and effects analysis is prospective.

Personal protective equipment and decontamination zones (hot, warm, cold) are essential in hazardous material incidents.

Sensitivity = true positives / (true positives + false negatives); specificity = true negatives / (true negatives + false positives).

Positive predictive value depends on prevalence; likelihood ratio positive = sensitivity / (1 - specificity) and is prevalence-independent.

Number needed to treat = 1 / absolute risk reduction; relative risk reduction can overstate benefit when baseline risk is low.

Levels of evidence: systematic reviews and randomised trials rank above cohort and case-control studies; case reports are lowest.

Randomised controlled trials reduce confounding by randomisation but may be limited by lack of blinding and intention-to-treat analysis issues.

Informed consent requires capacity, disclosure, understanding, and voluntariness; emergency exception applies when immediate treatment is life-saving and no proxy is available.

Confidentiality may be breached when required by law or when there is serious risk to the patient or others.

Publication bias and conflicts of interest threaten validity; check trial registration and funding in critical appraisal.