Neurocritical Care
Intracranial hypertension, severe TBI, ischemic stroke, status epilepticus, and brain death.
Core Topics
12 topicsAltered Consciousness, Coma, & Delirium in the ICU
ARAS neuroanatomy, structural vs toxic-metabolic coma, the comprehensive Coma Exam (pupils, cold calorics, posturing), FOUR score, and CAM-ICU delirium.
Status Epilepticus
Recognition and time-sensitive escalation of care for prolonged or repeated seizures.
Intracranial Hypertension & Cerebral Edema
Monro-Kellie doctrine, ICP waveforms (P2>P1, Lundberg A-waves), CPP targets (60–70 mmHg), herniation syndromes, and the 4-tier BTF management protocol.
Brain Death / Death by Neurologic Criteria (BD/DNC)
2023 AAN/AAP/CNS/SCCM consensus guideline: prerequisites, brainstem reflex examination, apnea testing on and off ECMO, valid ancillary tests, plus separate post-declaration donor-management principles.
Acute Ischemic Stroke
Core vs penumbra dynamics, ASPECTS & CT perfusion, Tenecteplase/Alteplase thrombolysis, DAWN/DEFUSE 3 extended thrombectomy, BP targets, and malignant MCA hemicraniectomy.
Intracranial Hemorrhage: ICH & SAH
Spontaneous ICH vs Aneurysmal SAH, INTERACT-2/ATACH-2 blood pressure targets, emergency anticoagulant reversal, ENRICH minimally invasive evacuation, ISAT coiling, and Nimodipine for delayed cerebral ischemia.
Severe Traumatic Brain Injury
Severe TBI neurocritical care: prevent hypoxemia/hypotension, treat intracranial hypertension, individualize ventilation/CPP, use evidence-based short antiseizure prophylaxis when chosen, and escalate surgery when indicated.
Acute Meningitis & Encephalitis
CT-before-LP criteria, CSF interpretation matrix, de Gans Dexamethasone timing, empiric age/host antimicrobial coverage + Ampicillin + Acyclovir, and neurocritical ICP management.
ICU Sedation, Analgesia, Delirium & Liberation
Analgesia-first sedation, light sedation targets, ABCDEF bundle, spontaneous breathing trials, and non-pharmacologic delirium mitigation.
ICU-Acquired Weakness (CIP/CIM)
Critical illness polyneuropathy and myopathy: recognition, risk reduction, diagnostic approach, ventilator liberation, rehabilitation, and prognosis.
Myasthenia Gravis & Myasthenic Crisis
Dedicated ICU management of myasthenic crisis: respiratory mechanics, airway timing, IVIG/plasma exchange, trigger control, medication hazards, and extubation.
Guillain–Barré Syndrome (GBS)
Dedicated ICU GBS care: respiratory surveillance, autonomic instability, IVIG/plasma exchange, airway strategy, pain/DVT prevention, and complications.
Clinical Problems & Bedside Triage
19 guidesAcute Hypercapnia & Ventilatory Failure
Triaging rising PaCO2: distinguishing acute uncompensated acidemia from chronic compensation, identifying central vs pump vs dead-space failure, and titrating noninvasive ventilation.
New Bradycardia & Conduction Blocks
Acute bradyarrhythmia management: identifying hemodynamic instability, distinguishing sinus node arrest vs high-grade AV block, medical chronotropic support (atropine, epinephrine), and emergent pacing.
Acute Severe Hypertension & Hypertensive Emergencies
Differentiating hypertensive emergency (acute target organ damage) from asymptomatic hypertension: tailored pressure targets for SCAPE, aortic dissection, hemorrhagic stroke, and ischemic stroke.
Acute Altered Mental Status & ICU Delirium
Systematic neurologic evaluation: immediate metabolic/toxic screening (glucose, hypoxia, hypercapnia), nonconvulsive status epilepticus exclusion, structural CT triage, and CAM-ICU delirium management.
New Focal Neurologic Deficit in the ICU
Rapid code-stroke protocol in critical illness: emergent non-contrast CT and CTA, distinguishing acute ischemic stroke (LVO candidate) from intracranial hemorrhage, and managing post-procedural neurological loss.
New Seizure & Status Epilepticus
Time-critical stepped seizure protocol: immediate airway/oxygen/glucose check, first-line IV benzodiazepines at 5 minutes, second-line non-sedating AEDs at 10–20 minutes, and general anesthetic induction at 30 minutes for refractory status.
Acute Coma & Loss of Brainstem Reflexes
Bedside evaluation of profound unresponsiveness: FOUR score and GCS, pupillary/corneal/caloric reflex examination, herniation syndrome recognition, confounder clearance, and Death by Neurologic Criteria (BD/DNC) evaluation.
Rapidly Progressive Weakness / Impending Ventilatory Failure
Bedside assessment and airway decision-making in rapidly ascending or fatiguable weakness risking ventilatory pump failure.
Severe Symptomatic Hyponatremia
Treat severe neurologic symptoms with controlled 3% saline boluses, then prevent overcorrection by separating the immediate symptom target from the 24-hour safety ceiling.
Severe Hypernatremia & Water Deficit
Bedside evaluation of severe hypernatremia: free-water deficit, ongoing losses, central vs nephrogenic diabetes insipidus, volume resuscitation, and individualized monitored sodium correction.
New Fever in the ICU & Suspected Infection
Systematic diagnostic workup of new ICU fever (T ≥ 38.3°C): line and device screening, pulmonary/abdominal/urinary source triage, distinguishing infectious vs non-infectious fever, and rational blood culturing.
Persistent Fever Despite Broad-Spectrum Antibiotics
Evaluating unresolved fever after 48–72 hours of antimicrobial therapy: undrained closed-space infection, resistant/fungal pathogens, catheter infections, C. difficile, drug fever, and ICU thrombosis.
Immunocompromised Patient with Fever + Organ Failure
Bedside diagnostic framing and emergency management of acute fever, sepsis, respiratory failure, or oncologic emergency in an immunocompromised host.
Critically Ill Pregnant or Postpartum Patient
Maternal-first stabilization with rapid differentiation of hypertensive, hemorrhagic, thromboembolic, septic, hepatic and cardiac obstetric emergencies.
Progressive Weakness with Impending Respiratory Failure
Use trajectory, bulbar function and respiratory mechanics to intubate before arrest and choose disease-specific therapy.
Severe Withdrawal With Agitation or Seizures
Hyperadrenergic delirium, hallucinations or seizures after alcohol/benzodiazepine reduction.
Agitation After Antipsychotic Exposure: QT Risk, EPS or NMS?
A complication-first bedside problem for an ICU patient exposed to antipsychotics who develops worsening agitation, rigidity, hyperthermia or electrical instability.
Raised ICP / Impending Herniation
Rapid neurologic deterioration with suspected intracranial hypertension requiring immediate physiologic stabilization, hyperosmolar rescue and urgent definitive neuroimaging/neurosurgical treatment.
Severe or Recurrent Hypoglycemia
Neuroglycopenia or recurrent low glucose requiring immediate glucose restoration, recurrence prevention and rapid investigation of drug, organ-failure, endocrine and nutritional causes.
Physiology Modules & Waveforms
3 conceptsCerebral Perfusion Pressure: CPP = MAP − ICP Dynamics
In the healthy brain, Cerebral Autoregulation maintains a constant Cerebral Blood Flow (CBF) across a wide range of CPP (50–150 mmHg) by dynamic arteriolar vasoconstriction and vasodilation. In severe traumatic brain injury, subarachnoid hemorrhage, or intracranial hypertension, autoregulation is frequently impaired or shifted rightward. Cerebral blood flow becomes passively dependent on perfusion pressure. When ICP rises (e.g., to 35 mmHg) and MAP is low or normal (e.g., 75 mmHg), CPP drops to 40 mmHg, below the critical ischemic threshold. Microvascular collapse occurs in the ischemic penumbra surrounding the brain contusion, triggering cellular ATP depletion, cytotoxic edema, and secondary brain infarction. Conversely, excessive CPP (>70–80 mmHg) drives vasogenic edema and increases the incidence of Acute Respiratory Distress Syndrome (ARDS).
Osmoregulation, ADH & Free Water Balance
Hypothalamic osmoreceptors detect changes in tonicity as small as 1%. When Posm exceeds 285 mOsm/kg, pituitary ADH release triggers insertion of aquaporin-2 water channels into collecting duct apical membranes, concentrating urine (Uosm > 600–800 mOsm/kg) and conserving free water. Non-osmotic stimuli (arterial baroreceptor unloading from hypovolemia, heart failure, cirrhosis, sepsis, pain, nausea, and stress) override osmotic inhibition. In these states, ADH is secreted even when serum osmolality is low, resulting in impaired free water excretion and dilutional hyponatremia if hypotonic fluids are administered.
Central DI vs Osmotic Diuresis Differentiation
In Central Diabetes Insipidus (e.g. post-transsphenoidal pituitary surgery, severe TBI, brain death), absolute deficiency of pituitary ADH prevents aquaporin-2 insertion in the collecting duct. The kidney cannot concentrate urine: urine is maximally dilute (Uosm < 100–200 mOsm/kg, specific gravity < 1.005), leading to rapid hypernatremic dehydration if free water is not replaced. In Osmotic Diuresis (e.g. DKA/HHS with glycosuria, post-mannitol administration, or urea excretion during post-AKI recovery), unreabsorbed high-concentration luminal solutes create an osmotic gradient that drags water and electrolytes along the tubule. Urine osmolality is isotonic or moderately concentrated (Uosm > 300 mOsm/kg), and total daily solute excretion is markedly elevated.
Clinical Reasoning Cases
7 casesRefractory Status Epilepticus (RSE)
Persistent status epilepticus after adequate benzodiazepine and second-line antiseizure therapy
Acute Intracranial Hypertension Crisis
Tiered management of intracranial hypertension after severe traumatic brain injury
Severe Symptomatic Hyponatremia with Seizures
Emergency hypertonic saline, close sodium monitoring, and prevention/rescue of overcorrection
Central Diabetes Insipidus / Arginine Vasopressin Deficiency
Post-operative water-balance emergency after pituitary surgery
Convulsive Status Epilepticus: First Contact
Immediate stabilization, adequate benzodiazepine dosing, and evidence-based second-line therapy
Mechanical Mitral Valve with Intracerebral Hemorrhage
Emergency VKA reversal followed by individualized anticoagulation resumption
Acute Liver Failure with Cerebral-Edema Risk
Hyperammonemia, osmotherapy, CRRT, and neuroprotection during transplant evaluation