Egyptian Board Critical Care cheat sheet

Type 1 (hypoxemic) respiratory failure: PaO2 < 60 mmHg on room air with normal or low PaCO2; type 2 (hypercapnic): PaCO2 > 45 mmHg with pH < 7.35.

Ventilator-induced lung injury is prevented with lung-protective settings in ARDS: tidal volume 6 mL/kg predicted body weight (range 4–8), plateau pressure ≤ 30 cmH2O, driving pressure ≤ 15 cmH2O.

Predicted body weight: male 50 + 0.91 × (height in cm − 152.4); female 45.5 + 0.91 × (height in cm − 152.4).

ARDS Berlin severity by PaO2/FiO2 on PEEP ≥ 5 cmH2O: mild 200–300, moderate 100–200, severe < 100 mmHg.

Permissive hypercapnia is acceptable in ARDS when pH ≥ 7.20; target oxygen saturation 88–95% to avoid hyperoxia and absorption atelectasis.

Auto-PEEP: check with an end-expiratory hold; reduce by shortening inspiratory time, lowering respiratory rate, treating bronchospasm, and accepting higher peak pressures.

Prone positioning for ≥ 16 h/day reduces mortality in moderate-severe ARDS (PaO2/FiO2 < 150 on FiO2 ≥ 0.6 and PEEP ≥ 5).

Criteria for weaning trial: PaO2/FiO2 > 150–200, PEEP ≤ 5–8 cmH2O, hemodynamic stability, ability to initiate breaths; rapid shallow breathing index (f/Vt) < 105 predicts success.

MAP = DBP + (SBP − DBP)/3; target MAP ≥ 65 mmHg in septic shock, higher (≥ 75–80) in chronic hypertension or elevated ICP.

Shock types: hypovolemic (low preload, high SVR), cardiogenic (high PCWP, low cardiac index), distributive (low SVR, high/normal CI), obstructive (high CVP, low CI).

Passive leg raise (45°) predicts fluid responsiveness: stroke volume or pulse pressure rise > 10% indicates preload reserve.

Pulse pressure variation > 13% and stroke volume variation > 10–12% predict fluid responsiveness only in sinus rhythm, controlled ventilation, tidal volume ≥ 8 mL/kg, and no spontaneous effort.

Cardiac output = heart rate × stroke volume; Fick principle: CO = VO2 / (CaO2 − CvO2).

ScvO2 < 70% in septic shock suggests inadequate oxygen delivery or increased extraction; > 80% may indicate impaired extraction or shunting.

Arterial line damping: over-damped underestimates SBP and overestimates DBP; under-damped exaggerates SBP and produces systolic overshoot.

Lactate ≥ 4 mmol/L or persistent hyperlactatemia (> 2 mmol/L after resuscitation) correlates with mortality; clearance indicates adequate perfusion.

Sepsis-3: life-threatening organ dysfunction from dysregulated host response to infection; organ dysfunction defined as SOFA increase ≥ 2 points.

Septic shock: sepsis plus vasopressor requirement to maintain MAP ≥ 65 mmHg and lactate > 2 mmol/L despite adequate fluid resuscitation.

qSOFA (RR ≥ 22, altered mentation, SBP ≤ 100) is a bedside risk-stratification screen, not a definition of sepsis.

Surviving Sepsis: broad-spectrum antibiotics within 1 hour for septic shock or high likelihood of sepsis; 30 mL/kg crystalloid for hypotension or lactate ≥ 4 mmol/L.

Blood cultures (two sets) and source cultures before antibiotics do not delay therapy; do not delay antibiotics > 45 minutes for cultures in shock.

Antimicrobial de-escalation: narrow based on culture results and clinical response at 48–72 hours; daily review of need and duration.

Procalcitonin can support antibiotic discontinuation when < 0.5 ng/mL or falling > 80% from peak, but is not a standalone rule-out test.

Source control (drainage, debridement, device removal) within 6–12 hours of diagnosis is essential; delay increases mortality.

ACS: dual antiplatelet therapy plus anticoagulation; STEMI requires reperfusion (PCI) within 90 minutes of first medical contact at a PCI-capable center.

Cardiogenic shock in ACS: norepinephrine or epinephrine to maintain MAP, plus inotrope (dobutamine) if low cardiac output; early revascularization improves survival.

Ventricular tachycardia with a pulse and instability: synchronized cardioversion; pulseless VT/VF: defibrillation immediately with CPR.

Atrial fibrillation with rapid ventricular response and hemodynamic instability: synchronized cardioversion; otherwise rate control with beta-blocker or amiodarone (avoid in pre-excitation).

Torsades de pointes: IV magnesium sulfate 2 g; correct hypokalemia and hypomagnesemia; stop QT-prolonging drugs.

Complete heart block or Mobitz II: transcutaneous pacing then transvenous pacing; atropine is unlikely to help infranodal block.

Aortic dissection: type A (ascending) is a surgical emergency; control heart rate (target 60 bpm) and blood pressure (SBP 100–120) with beta-blockade first, then vasodilator.

Post-cardiac arrest: targeted temperature management 32–36 °C for ≥ 24 h in comatose survivors, with avoidance of fever afterward.

Glasgow Coma Scale: eye 1–4, verbal 1–5, motor 1–6; score ≤ 8 generally indicates need for airway protection.

Cerebral perfusion pressure (CPP) = MAP − ICP; target CPP 60–70 mmHg in TBI, ICP < 22 mmHg.

ICP management: head elevation 30°, normocapnia (PaCO2 35–40), sedation, osmotic therapy (mannitol 0.25–1 g/kg or hypertonic saline), CSF drainage.

Brief hyperventilation to PaCO2 30–35 mmHg is a temporizing bridge for herniation, not a sustained therapy.

Pupillary exam: fixed dilated pupil suggests uncal herniation; bilateral fixed pupils suggest poor prognosis; use pupillometry if available.

Status epilepticus: benzodiazepine first-line, then second-line (levetiracetam, valproate, or fosphenytoin); refractory requires anesthetic doses and continuous EEG.

Subarachnoid hemorrhage: nimodipine 60 mg every 4 h for 21 days reduces delayed ischemic neurologic deficit; monitor for rebleeding and hyponatremia.

Ischemic stroke: thrombolysis within 4.5 h of last known well; thrombectomy up to 24 h in selected large-vessel occlusion with favorable imaging.

AKI KDIGO: stage 1 = creatinine rise ≥ 0.3 mg/dL in 48 h or 1.5–1.9× baseline; stage 2 = 2.0–2.9×; stage 3 = ≥ 3× or creatinine ≥ 4.0 mg/dL or urine output < 0.3 mL/kg/h for ≥ 24 h.

Urine output < 0.5 mL/kg/h for 6 h defines oliguria; fractional excretion of sodium < 1% suggests prerenal AKI.

Hyperkalemia with ECG changes: IV calcium gluconate first, then insulin/glucose, beta-agonist, and removal (diuretics, binder, dialysis).

Anion gap = Na − (Cl + HCO3); normal 8–12 mEq/L; correct for hypoalbuminemia by adding 2.5 per 1 g/dL albumin below 4.

Winter's formula: expected PaCO2 = 1.5 × HCO3 + 8 ± 2 for metabolic acidosis; deviation indicates a mixed disorder.

Hyponatremia: correct ≤ 8–10 mmol/L in 24 h to avoid osmotic demyelination; hypertonic saline for severe symptoms.

Hypernatremia: free water deficit = 0.6 × weight (kg) × (Na/140 − 1); correct ≤ 10 mmol/L per 24 h.

RRT indications: refractory acidosis, electrolyte disturbance (especially potassium), intoxication, overload, uremia (AEIOU); CRRT preferred in hemodynamic instability.

Diabetic ketoacidosis: IV fluids first, then insulin infusion 0.1 U/kg/h; add dextrose when glucose < 200–250 mg/dL; monitor potassium and replace when < 5.2 mEq/L.

DKA resolution: ketones < 0.6 mmol/L or anion gap ≤ 12 with bicarbonate ≥ 15; not based on glucose alone.

Hyperosmolar hyperglycemic state: profound dehydration, glucose often > 600 mg/dL, minimal ketosis; mortality higher than DKA.

Thyroid storm: Burch-Wartofsky score; treat with beta-blocker, thionamide, iodine (at least 1 h after thionamide), and glucocorticoid.

Myxedema coma: IV levothyroxine plus stress-dose hydrocortisone until adrenal insufficiency is excluded; passive rewarming and ventilatory support.

Adrenal crisis: hydrocortisone 100 mg IV then 50 mg every 6 h; do not wait for cortisol results if shock is unexplained.

SIADH: euvolemic hyponatremia with urine osmolality > 100 mOsm/kg and urine Na > 30–40 mEq/L; treat with fluid restriction and, if severe, hypertonic saline.

Refeeding syndrome: start feeding at 10–20 kcal/kg/day in high-risk patients, monitor phosphate, potassium, and magnesium; replace thiamine before feeding.

ATLS primary survey: airway with cervical spine protection, breathing, circulation with hemorrhage control, disability, exposure; treat life threats as found.

Massive transfusion protocol: balanced 1:1:1 ratio of plasma:platelets:PRBC approximates reconstituted whole blood; give tranexamic acid within 3 h of trauma.

Permissive hypotension (SBP 80–90) is acceptable in penetrating trauma without TBI until hemorrhage control; avoid in TBI (target SBP ≥ 110).

Burn resuscitation: Parkland formula 4 mL/kg/%TBSA lactated Ringer's in first 24 h, half in first 8 h; titrate to urine output 0.5–1 mL/kg/h.

Burn airway: suspect inhalation injury with facial burns, singed nares, soot in sputum, hoarseness, or enclosed-space fire; intubate early before edema worsens.

Abdominal compartment syndrome: intra-abdominal pressure > 20 mmHg with new organ dysfunction; decompress with laparotomy or percutaneous drainage.

Damage control surgery: stop bleeding, control contamination, temporary closure, then ICU resuscitation before definitive repair.

Rhabdomyolysis: aggressive crystalloid to target urine output 200–300 mL/h; monitor potassium, phosphate, and creatine kinase.

Toxidrome recognition: anticholinergic (dry, hot, flushed, mydriasis, delirium), cholinergic (SLUDGE, bradycardia, miosis), opioid (miosis, respiratory depression), sympathomimetic (tachycardia, hypertension, agitation).

Acetaminophen toxicity: N-acetylcysteine based on Rumack-Matthew nomogram at 4 h post-ingestion; use regardless of time if hepatotoxicity or unknown timing.

Salicylate toxicity: alkaline diuresis with sodium bicarbonate; dialysis for severe cases (level > 100 mg/dL, seizures, renal failure, pulmonary edema).

Tricyclic overdose: sodium bicarbonate for QRS > 100 ms or arrhythmia; avoid class IA/IC antiarrhythmics and flumazenil.

Carbon monoxide: 100% oxygen; hyperbaric oxygen for severe poisoning (syncope, neurologic deficit, COHb > 25%, pregnancy with COHb > 15%).

Organophosphate poisoning: atropine titrated to secretions and bronchorrhea, plus pralidoxime; decontaminate before exposure.

Beta-blocker overdose: glucagon first, then high-dose insulin euglycemia therapy or calcium; pacemaker for refractory bradycardia.

Metformin-associated lactic acidosis: stop drug, support hemodynamics, and use intermittent hemodialysis for severe acidosis or renal failure.

Difficult airway prediction: Mallampati III–IV, thyromental distance < 6 cm, mouth opening < 3 cm, limited neck extension, obesity, obstructions.

RSI: preoxygenate, pretreat if indicated, induce (ketamine, etomidate, propofol), paralyze with rocuronium 1.2 mg/kg or succinylcholine 1.5 mg/kg, then intubate within 45–60 s.

Failed airway algorithm: optimize attempts (≤ 3), call for help, use rescue device (supraglottic airway, video laryngoscope), and if cannot intubate/cannot ventilate, perform surgical cricothyrotomy.

Central line: ultrasound guidance, Seldinger technique; confirm with manometry or ultrasound; place internal jugular or subclavian to reduce infection versus femoral.

Chest tube: insert at 4th–5th intercostal space anterior to midaxillary line, above the rib; confirm with chest X-ray and watch for re-expansion edema.

Defibrillation energy: biphasic 120–200 J (per manufacturer), monophasic 360 J; resume CPR immediately after shock for 2 minutes.

Post-ROSC care: targeted temperature management, avoid hyperoxia, treat hypotension (MAP ≥ 65), 12-lead ECG, and early PCI if STEMI.

Arterial line: radial first; Allen test not required with ultrasound; transduce at phlebostatic axis (4th intercostal space, midaxillary line).

Informed consent requires capacity, disclosure, understanding, voluntariness, and authorization; emergency treatment may proceed under implied consent.

Capacity assessment: patient can communicate a choice, understand relevant information, appreciate consequences, and reason about options.

Withholding and withdrawing life-sustaining treatment are ethically equivalent; the goal is proportionate care aligned with patient values.

Advance directives and durable power of attorney for healthcare should be honored; if absent, use a surrogate per local law and best-interest standard.

Brain death determination requires established etiology, unresponsive coma, absent brainstem reflexes, apnea test, and exclusion of confounders (sedation, hypothermia, metabolic).

ICU triage during resource scarcity: prioritize by short-term survival benefit and SOFA-based scoring, not by age alone or social worth.

ICU-acquired weakness prevention: early mobilization, minimizing sedation, and avoiding prolonged paralysis; no proven pharmacologic therapy.

Family meetings within 48–72 h of ICU admission reduce ICU length of stay and improve goal-concordant care; document shared decision-making.

Light sedation (RASS −2 to 0) is preferred; use validated scales (RASS, SAS) and daily sedation interruption or protocolized sedation.

Delirium: CAM-ICU or ICDSC screening; non-pharmacologic bundle (orientation, sleep, early mobility, family) first; avoid benzodiazepines.

Analgesia-first sedation reduces opioid and sedative doses; fentanyl or morphine preferred in hemodynamically unstable patients.

Feeding: start enteral nutrition within 24–48 h in critically ill patients; trophic feeding is acceptable in shock with escalating vasopressors.

Ventilator-associated pneumonia prevention: head of bed 30–45°, oral chlorhexidine or oral care, daily sedation interruption, avoid unnecessary circuit changes.

Stress ulcer prophylaxis: PPI or H2 blocker for patients with risk factors (mechanical ventilation > 48 h, coagulopathy, prior GI bleed); discontinue when risk resolves.

VTE prophylaxis: LMWH or UFH in all ICU patients unless contraindicated; mechanical prophylaxis when bleeding risk is high.

Catheter-related bloodstream infection prevention: hand hygiene, chlorhexidine skin antisepsis, full barrier precautions, daily line review, and prompt removal.

Dead space fraction (Vd/Vt) > 0.6 correlates with mortality in ARDS; estimate with volumetric capnography.

Oxygen content: CaO2 = 1.34 × Hb × SaO2 + 0.003 × PaO2; anemia reduces oxygen delivery despite normal saturation.

Recruitment maneuvers: sustained inflation of 30–40 cmH2O for 30–40 s; avoid in hypovolemia or bullous disease.

High-flow nasal cannula delivers up to 60 L/min with FiO2 up to 1.0 and modest PEEP; used in acute hypoxemic respiratory failure.

Noninvasive ventilation is preferred in COPD exacerbation and acute cardiogenic pulmonary edema; avoid in altered mental status or facial trauma.

Extubation criteria: cuff leak present, adequate cough, minimal secretions, successful spontaneous breathing trial for 30–120 min.

Ventilator asynchrony: flow starvation, double triggering, ineffective triggering; adjust flow, trigger sensitivity, or sedation.

Permissive hypercapnia is contraindicated in raised ICP; maintain PaCO2 35–40 mmHg in neurocritical patients.

CVP is a poor predictor of fluid responsiveness; use dynamic indices, passive leg raise, or bedside echocardiography.

Cardiac index normal 2.5–4.0 L/min/m2; SVR = (MAP − CVP) × 80 / CO (normal 800–1200 dyn·s·cm−5).

Pulmonary artery catheter: PCWP ≤ 18 suggests preload reserve; > 18 suggests cardiogenic or fluid overload.

Norepinephrine is first-line vasopressor in septic shock; add vasopressin 0.03 U/min or epinephrine to reduce norepinephrine dose.

Dobutamine 2.5–20 µg/kg/min increases contractility and cardiac output; may worsen hypotension via beta-2 vasodilation.

Mixed venous oxygen saturation (SvO2) < 65% suggests inadequate oxygen delivery; ScvO2 from central line approximates SvO2.

Capillary refill time > 3 s and mottling score correlate with hypoperfusion and mortality in septic shock.

Fluid bolus 250–500 mL crystalloid reassessed after each bolus; avoid fluid loading in cardiogenic shock without echocardiographic assessment.

SOFA score components: PaO2/FiO2, platelets, bilirubin, MAP/vasopressors, GCS, creatinine/urine output; each 0–4, total 0–24.

Vasopressor initiation: norepinephrine first; add vasopressin for refractory shock; epinephrine for refractory or cardiac dysfunction.

Antibiotic pharmacokinetics in sepsis: increased volume of distribution and augmented renal clearance may require higher doses or extended infusions (e.g., beta-lactams).

MRSA risk factors: recent hospitalization, invasive devices, prior MRSA colonization; add vancomycin or linezolid empirically when risk is high.

Fungal infection risk: prolonged broad-spectrum antibiotics, TPN, abdominal surgery, colonization with Candida; echinocandin first-line for candidemia.

Clostridioides difficile: oral vancomycin or fidaxomicin; avoid antiperistaltics; isolate patient and use soap-and-water handwashing.

Antimicrobial stewardship: prospective audit and feedback, formulary restriction, and 48–72 h antibiotic time-out reduce resistance and cost.

Sepsis readmission prevention: vaccination, source control follow-up, and discharge antibiotic plan review reduce recurrence.

ECG in ACS: ST elevation in ≥ 2 contiguous leads or new LBBB; posterior MI shows ST depression in V1–V3 with tall R waves.

Right ventricular infarction: ST elevation in V4R; avoid nitrates and preload reduction; give fluids.

Heart failure with pulmonary edema: noninvasive ventilation, nitrates, and diuretics; inotropes only for low output with hypotension.

Pulmonary embolism: high-risk with hypotension requires thrombolysis or embolectomy; submassive with RV strain monitored closely.

Hypertensive emergency: reduce MAP by ≤ 25% in first hour, then to 160/100 over 2–6 h; exceptions are aortic dissection and ischemic stroke.

Amiodarone loading 150 mg IV over 10 min, then 1 mg/min for 6 h, then 0.5 mg/min; monitor for hypotension and QT prolongation.

Digoxin toxicity: bradycardia and arrhythmias, hyperkalemia; treat with digoxin-specific Fab fragments for life-threatening toxicity.

Pericardial tamponade: Beck triad (hypotension, distended neck veins, muffled heart sounds); treat with pericardiocentesis and fluid bolus as bridge.

TBI: avoid hypotension (SBP < 90) and hypoxia (SpO2 < 90); both independently worsen outcome.

Sedation for ICP control: propofol (monitor for propofol infusion syndrome) or midazolam; avoid ketamine only if hemodynamically unstable.

Hypertonic saline 3% bolus 100–250 mL or 23.4% 30 mL for herniation; monitor sodium every 4–6 h.

Seizure prophylaxis after TBI is recommended for 7 days to prevent early post-traumatic seizures; not for late prevention.

Spinal cord injury: maintain MAP 85–90 mmHg for 7 days after acute injury; avoid hypoxia and hypotension.

Guillain-Barré syndrome: monitor vital capacity; intubate if < 15 mL/kg or declining > 30%; IVIG or plasma exchange.

Myasthenic crisis: respiratory monitoring, plasma exchange or IVIG, and avoid aminoglycosides and magnesium.

Brain death apnea test: preoxygenate, disconnect ventilator, observe for respiratory effort; abort if SBP falls or desaturation occurs.

Metabolic alkalosis: assess urine chloride; < 20 mEq/L suggests chloride-responsive (vomiting, diuretics), treat with saline; > 20 suggests mineralocorticoid excess.

Hypercalcemia: IV fluids first, then calcitonin, bisphosphonate, or dialysis for severe or refractory cases.

Hypocalcemia: corrected calcium = measured Ca + 0.8 × (4.0 − albumin); treat symptomatic with IV calcium gluconate.

Hypophosphatemia < 1 mg/dL or symptomatic: IV phosphate replacement; watch for calcium precipitation.

Contrast-induced AKI prevention: hydration with isotonic saline; avoid nephrotoxins; no proven benefit from bicarbonate or N-acetylcysteine.

Hyperkalemia ECG changes: peaked T waves, widened QRS, sine wave; treat before ECG changes in severe cases.

Metabolic acidosis with normal anion gap: diarrhea, RTA, saline resuscitation; check urine pH and urine anion gap.

Continuous renal replacement therapy: dialysate flow 20–30 mL/kg/h; monitor filter clotting and electrolytes every 4–6 h.

DKA fluid: isotonic saline 15–20 mL/kg in first hour, then 250–500 mL/h; switch to dextrose-containing fluid when glucose < 200–250 mg/dL.

Insulin infusion in DKA: 0.1 U/kg/h; do not start until potassium > 3.3 mEq/L to avoid arrhythmia.

Thyroid storm treatment order: beta-blocker → thionamide → iodine → glucocorticoid; do not give iodine before thionamide.

Pheochromocytoma crisis: alpha-blockade (phentolamine or phenoxybenzamine) before beta-blockade to avoid unopposed alpha stimulation.

Carcinoid crisis: octreotide 100–500 µg IV; avoid catecholamines that trigger mediator release.

Adrenal insufficiency: hyponatremia, hyperkalemia, hypoglycemia, hypotension; cosyntropin stimulation test if stable.

Hypertriglyceridemia-induced pancreatitis: insulin infusion or plasmapheresis for severe hypertriglyceridemia (> 1000 mg/dL).

Obesity hypoventilation: hypercapnia with BMI > 30; treat with noninvasive ventilation and weight management.

Hemorrhagic shock classes: class I < 15% blood loss, class II 15–30%, class III 30–40%, class IV > 40%; tachycardia and narrowed pulse pressure appear in class II–III.

FAST exam detects free fluid in pericardial, perihepatic, perisplenic, and pelvic windows; positive FAST with instability prompts laparotomy.

Tranexamic acid 1 g IV over 10 min then 1 g over 8 h within 3 h of trauma reduces mortality.

Burn depth: superficial partial-thickness is painful and blistered; full-thickness is insensate and leathery; deep burns may require excision.

Electrical burns: monitor for cardiac arrhythmias, rhabdomyolysis, and compartment syndrome; fluids guided by urine output.

Open abdomen: negative pressure wound therapy with fascial traction; watch for fistula and intra-abdominal infection.

Postoperative fever workup: atelectasis, pneumonia, urinary tract infection, wound infection, DVT; use cultures and imaging, not empiric antibiotics alone.

Necrotizing soft tissue infection: immediate surgical debridement plus broad-spectrum antibiotics including clindamycin for toxin suppression.

Opioid overdose: naloxone 0.04–0.4 mg IV titrated to respiratory rate; repeat or infuse because naloxone half-life is shorter than most opioids.

Methanol or ethylene glycol: fomepizole first-line; dialysis for severe acidosis, visual symptoms, or high levels.

Cyanide: hydroxocobalamin 5 g IV; suspect in smoke inhalation with lactic acidosis and normal PaO2.

Serotonin syndrome: clonus, hyperreflexia, agitation; stop serotonergic drugs and use benzodiazepines; cyproheptadine for severe cases.

Neuroleptic malignant syndrome: rigidity, hyperthermia, autonomic instability, elevated CK; stop antipsychotic, use dantrolene or bromocriptine.

Alcohol withdrawal: benzodiazepines symptom-triggered with CIWA-Ar; thiamine before glucose to prevent Wernicke encephalopathy.

Hypothermia: rewarm to 32–35 °C; use extracorporeal rewarming for severe (< 28 °C) or cardiac arrest.

Heat stroke: rapid cooling to < 39 °C within 30 min; avoid antipyretics and monitor for DIC and rhabdomyolysis.

Preoxygenation for 3–5 min with FiO2 1.0 or 4 vital capacity breaths; apneic oxygenation with nasal cannula 15 L/min prolongs safe apnea time.

Video laryngoscopy improves first-pass success in difficult airways and reduces cervical spine movement.

Supraglottic airway: second-generation devices (LMA Supreme, i-gel) allow higher seal pressure and gastric drainage; use as rescue or bridge.

Needle decompression for tension pneumothorax: 2nd intercostal space midclavicular line or 4th–5th space anterior axillary; follow with tube thoracostomy.

Pericardiocentesis: subxiphoid approach with ultrasound; remove 50–100 mL initially for tamponade; leave catheter for drainage.

Lumbar puncture: avoid in coagulopathy or signs of raised ICP; perform CT first if focal deficit or altered mental status.

Arterial blood gas interpretation: check pH, PaCO2, HCO3, and compensation; calculate A-a gradient (normal < 15–20 mmHg on room air).

CPR quality: compression rate 100–120/min, depth 5–6 cm, full recoil, minimize interruptions < 10 s, and change compressor every 2 min.

ICU admission criteria: need for organ support, monitoring, or life-sustaining therapy that cannot be provided elsewhere; avoid admission for comfort-only care.

Do-not-resuscitate orders do not preclude other treatments; clarify which interventions are desired.

Palliative care consultation in ICU improves symptom control and family satisfaction; it is not limited to end-of-life care.

Organ donation: brain-dead patients may be donors; donation after circulatory death requires controlled withdrawal and rapid procurement.

Medical futility disputes: use institutional ethics consultation, second opinions, and legal processes; avoid unilateral withdrawal without due process.

Documentation of family meetings should include participants, prognosis, goals, decisions, and follow-up plan.

ICU staffing: high-intensity intensivist staffing (24/7) is associated with lower mortality and length of stay.

Quality metrics: standardized mortality ratio, ICU length of stay, ventilator-associated events, central line infections, and readmission rates.

Bispectral index (BIS) monitoring may reduce awareness in paralysis; not routinely recommended in ICU sedation.

Daily interruption of sedation reduces ventilator days and ICU length of stay; combine with spontaneous awakening and breathing trials.

Delirium risk factors: age, dementia, sepsis, benzodiazepines, anticholinergics, immobility, sleep deprivation, and alcohol withdrawal.

Enteral nutrition: gastric feeding preferred; post-pyloric feeding for high aspiration risk or gastroparesis.

Parenteral nutrition: reserve for enteral failure or short bowel; start after 3–7 days in well-nourished patients.

ICU-acquired weakness: electrophysiology shows critical illness polyneuropathy or myopathy; prevention is early mobility and glycemic control.

Pressure injuries: reposition every 2 h, use pressure-redistribution surfaces, and monitor nutrition and moisture.

Sleep in ICU: reduce noise and light at night, cluster care, and use earplugs and eye masks; melatonin not proven.

Mode selection: volume-control guarantees tidal volume; pressure-control limits pressure; pressure-support used in spontaneous breathing.

Peak pressure minus plateau pressure > 10 cmH2O suggests increased airway resistance (bronchospasm, secretions, tube obstruction).

Plateau pressure minus PEEP (driving pressure) reflects alveolar distension; target ≤ 15 cmH2O.

Ventilator-associated lung injury mechanisms: volutrauma, barotrauma, atelectrauma, biotrauma.

ECMO in ARDS: consider when PaO2/FiO2 < 80 despite optimized ventilation, or pH < 7.25 with PaCO2 > 60 despite protective settings.

Airway pressure release ventilation (APRV) may improve recruitment but evidence for mortality benefit is limited.

Cuff pressure: maintain 20–30 cmH2O to prevent microaspiration and tracheal ischemia.

Tracheostomy timing: consider after 10–14 days of ventilation if prolonged weaning expected; early tracheostomy may reduce sedation and ICU stay.

Stroke volume variation and pulse pressure variation lose reliability in atrial fibrillation, spontaneous breathing, and low tidal volume ventilation.

Echocardiography in shock: assess LV function, RV strain, pericardial effusion, and IVC collapsibility as a rapid bedside tool.

Vasopressor extravasation: phentolamine 5–10 mg in 10 mL saline infiltrated locally for norepinephrine or dopamine.

Peripheral vasopressor use is increasingly accepted with a well-positioned peripheral line and close monitoring for extravasation.

Anaphylactic shock: epinephrine 0.3–0.5 mg IM in the thigh; IV infusion for refractory shock; fluids and adjuncts (H1/H2 blockers, steroids).

Obstructive shock: tension pneumothorax, tamponade, massive PE, and abdominal compartment syndrome; treat the cause immediately.

Lactate clearance > 10% over 2 h suggests improving perfusion; persistent elevation warrants reassessment of source and cardiac output.

Blood pressure cuff size: too small a cuff overestimates blood pressure; cuff bladder should encircle 80% of arm circumference.

Neutropenic sepsis: start empiric anti-pseudomonal beta-lactam within 60 min; add vancomycin for catheter infection or MRSA risk.

Ventilator-associated pneumonia: empiric coverage based on local antibiogram; 7-day course is adequate for most patients.

Blood culture contamination: reduce with sterile technique and separate venipunctures; do not treat single coagulase-negative staphylococcus without clinical correlation.

Vancomycin dosing: target AUC/MIC 400–600 for MRSA; monitor renal function and troughs if AUC unavailable.

Aminoglycoside dosing: extended-interval once-daily; monitor trough and renal function; avoid in myasthenia gravis.

Antibiotic allergy: clarify reaction type; direct challenges or skin testing can de-label many penicillin allergies.

Sepsis bundle compliance: measure time to antibiotics, fluids, cultures, lactate, and vasopressors; audit and feedback improve performance.

Infection control: hand hygiene, contact precautions for resistant organisms, and environmental cleaning reduce ICU transmission.

STEMI complications: ventricular septal rupture, papillary muscle rupture, free wall rupture; suspect with new murmur or shock after MI.

Cardiogenic shock from acute MI: early revascularization plus mechanical circulatory support (IABP, Impella) in selected patients.

Atrial fibrillation anticoagulation: CHA2DS2-VASc score; in ICU, assess bleeding risk and use heparin if indicated.

Supraventricular tachycardia: vagal maneuvers first, then adenosine 6 mg IV; avoid in severe asthma or pre-excitation.

Bradycardia with hypotension: atropine 0.5 mg IV every 3–5 min up to 3 mg; then pacing or epinephrine/dopamine infusion.

Long QT: avoid ondansetron, haloperidol, macrolides, fluoroquinolones; correct potassium to > 4.0 and magnesium > 2.0.

Heart transplant patients: denervated heart; atropine ineffective; use isoproterenol or pacing for bradycardia.

Aortic stenosis in critical illness: avoid tachycardia and hypotension; maintain preload and afterload; consider balloon valvuloplasty as bridge.

Pupillary light reflex and corneal reflex are brainstem functions; absent reflexes with apnea suggest brain death.

ICP waveform: P1 (percussive), P2 (tidal), P3 (dicrotic); elevated P2 suggests decreased compliance.

Transcranial Doppler: elevated mean flow velocity > 120 cm/s suggests vasospasm after subarachnoid hemorrhage.

Status epilepticus: obtain EEG within 24 h in comatose patients; non-convulsive seizures are common.

Hyponatremia in SAH: often cerebral salt wasting with hypovolemia; treat with saline, not fluid restriction.

ICU delirium in neuro patients: use CAM-ICU; differentiate from aphasia and agitation; treat underlying cause.

Traumatic brain injury: avoid hyperthermia; maintain normothermia and normoglycemia; seizure prophylaxis for 7 days.

Spinal shock: flaccid paralysis and hypotension after acute spinal cord injury; distinguish from neurogenic shock (bradycardia, hypotension).

Acid-base: pH < 7.35 with HCO3 < 22 is metabolic acidosis; calculate anion gap and Winter's formula.

Respiratory acidosis: acute rise in PaCO2 of 10 increases HCO3 by 1; chronic rise increases HCO3 by 3–4 per 10 mmHg.

Respiratory alkalosis: acute fall in PaCO2 of 10 decreases HCO3 by 2; chronic decreases by 4–5 per 10 mmHg.

Metabolic alkalosis: compensation is hypoventilation; do not expect full correction; treat cause.

Hyponatremia symptoms: seizures, coma, vomiting; use 3% saline 100–150 mL bolus, repeat up to 3 times, target rise 4–6 mmol/L.

Hyperkalemia in dialysis patients: shift with insulin/glucose and beta-agonist, then dialyze; calcium for cardiac protection.

AKI in sepsis: avoid nephrotoxins, maintain perfusion pressure, and consider early RRT for fluid overload or refractory acidosis.

Diuretic resistance: combine loop diuretic with thiazide or use continuous infusion; monitor electrolytes and renal function.

DKA potassium: total body potassium depleted even if serum normal; replace when < 5.2 mEq/L and urine output adequate.

HHS fluid deficit: often 100–200 mL/kg; correct sodium slowly and monitor osmolality.

Thyroid storm Burch-Wartofsky score ≥ 45 highly suggestive; treat empirically if suspected.

Myxedema coma: hypothermia, bradycardia, hypoventilation, hyponatremia; mortality high; treat in ICU.

Adrenal crisis: do not delay hydrocortisone for cosyntropin test; draw sample then treat.

Pheochromocytoma: avoid unopposed beta-blockade; use alpha-blockade first, then beta-blockade.

Hypercalcemic crisis: IV fluids, calcitonin, bisphosphonate; dialysis for severe renal failure.

Hypoglycemia in ICU: target glucose 140–180 mg/dL; avoid < 70 mg/dL; use dextrose 50% 25 g IV for severe hypoglycemia.

Burn TBSA estimation: rule of nines (head 9%, each arm 9%, each leg 18%, trunk 36%, perineum 1%); Lund-Browder more accurate in children.

Inhalation injury: early bronchoscopy; avoid routine steroids; use nebulized heparin and albuterol in selected cases.

Burn wound infection: monitor for sepsis, graft loss, and invasive wound infection; use topical antimicrobials (silver sulfadiazine, mafenide).

Abdominal trauma: hemodynamically stable with solid organ injury may be managed nonoperatively with close monitoring.

Pelvic fracture: bind pelvis, control hemorrhage with angioembolization or packing; avoid repeated pelvic exams.

Traumatic brain injury: avoid hypotension and hypoxia; maintain CPP; repeat CT for neurologic decline.

Fat embolism syndrome: hypoxemia, petechiae, confusion after long bone fracture; supportive care.

Postoperative respiratory failure: consider atelectasis, aspiration, pulmonary embolism, and anastomotic leak; use CT and bronchoscopy as indicated.

Activated charcoal: within 1 h of ingestion for most toxins; avoid in altered mental status, caustic ingestion, or hydrocarbon aspiration risk.

Whole bowel irrigation: polyethylene glycol for iron, lithium, or sustained-release drug overdose; avoid in obstruction.

Lithium toxicity: tremor, ataxia, seizures; dialysis for severe toxicity (level > 4 mEq/L or renal failure).

Iron overdose: abdominal pain, vomiting, metabolic acidosis; deferoxamine for severe toxicity.

Digoxin overdose: hyperkalemia, bradycardia; Fab fragments for life-threatening arrhythmia or hyperkalemia.

Cocaine toxicity: benzodiazepines first; avoid beta-blockers alone due to unopposed alpha stimulation; sodium bicarbonate for wide QRS.

Methanol: visual disturbances, metabolic acidosis, elevated osmolal gap; fomepizole and dialysis.

Snake envenomation: immobilize, avoid incision or suction; antivenom for systemic or progressive local signs.

Bag-mask ventilation: two-person technique with airway adjuncts improves seal and reduces gastric insufflation.

Cricothyrotomy: vertical skin incision, horizontal cricothyroid membrane incision, insert tube; use in cannot intubate/cannot ventilate.

Thoracentesis: ultrasound guidance, avoid intercostal vessels; limit fluid removal to 1–1.5 L per session to prevent re-expansion edema.

Paracentesis: avoid in DIC or severe coagulopathy; use ultrasound; remove up to 5 L with albumin replacement (6–8 g per liter removed).

Arterial puncture: radial site, compress 5 min; avoid in severe coagulopathy or poor collateral flow.

Central venous pressure waveform: a, c, v waves and x, y descents; cannon a waves in AV dissociation; absent a waves in AF.

Intraosseous access: proximal tibia or humerus; use for emergency drugs and fluids when IV access fails.

Defibrillation in pregnancy: same energy; left uterine displacement to improve venous return; perimortem cesarean within 4 min if no ROSC.

Informed refusal: patient with capacity may refuse treatment even if life-sustaining; document capacity and discussion.

Minors: consent from parent or guardian; emancipated minors may consent; emergency exceptions apply.

Confidentiality: disclose only to those involved in care; use minimum necessary information.

Research ethics: informed consent, institutional review board approval, and equipoise; emergency research may use exception from informed consent.

Resource allocation: use transparent, consistent criteria; avoid discrimination based on disability or age alone.

End-of-life symptom management: opioids and benzodiazepines for dyspnea and agitation; do not hasten death intentionally.

Family bereavement support: provide information, allow presence at death, and offer follow-up.

ICU discharge planning: medication reconciliation, follow-up appointments, and communication with primary team reduce readmissions.

Capnography: end-tidal CO2 correlates with PaCO2 in stable patients; sudden drop suggests tube disconnection or cardiac arrest.

Pulse oximetry: unreliable in poor perfusion, motion, or abnormal hemoglobin (carboxyhemoglobin, methemoglobin).

Central venous oxygen saturation: continuous monitoring with oximetric catheter; target > 70% in early septic shock resuscitation.

Gastric residual volume: routine monitoring not recommended; check only for symptoms of intolerance.

Nutrition assessment: use NUTRIC or NRS-2002; high-risk patients benefit from early enteral nutrition.

Glycemic control: target 140–180 mg/dL; avoid intensive control < 110 mg/dL due to hypoglycemia risk.

Mobility: early mobilization within 24–48 h reduces ICU-acquired weakness and delirium; use a progressive protocol.

Fungal infection prevention: avoid unnecessary broad-spectrum antibiotics and use antifungal stewardship; fluconazole prophylaxis in high-risk surgical ICU patients.