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Elevated Intracranial Pressure Management

VERSION: 1.0 CREATED: January 27, 2026 STATUS: Approved


DIAGNOSIS: Elevated Intracranial Pressure (ICP) / Intracranial Hypertension

ICD-10: G93.2 (Benign intracranial hypertension [IIH]), G93.5 (Compression of brain), G93.6 (Cerebral edema), G91.1 (Obstructive hydrocephalus), G91.2 (Normal pressure hydrocephalus), S06.1X (Traumatic cerebral edema)

CPT CODES: 85025 (CBC with differential), 80053 (CMP (BMP + LFTs)), 82947 (Blood glucose), 85610 (PT/INR), 83930 (Serum osmolality), 82803 (Arterial blood gas (ABG)), 83605 (Lactate), 86900 (Type and screen), 84484 (Troponin), 82533 (Cortisol (AM, random)), 84443 (TSH), 82140 (Ammonia), 80307 (Toxicology screen), 70450 (CT head without contrast), 70496 (CT angiography (CTA) head), 70553 (MRI brain with and without contrast), 71046 (Chest X-ray), 93886 (Transcranial Doppler (TCD)), 95700 (Continuous EEG monitoring), 62270 (LP with opening pressure)

SYNONYMS: Elevated intracranial pressure, elevated ICP, intracranial hypertension, raised ICP, high ICP, cerebral edema, brain swelling, herniation syndrome, increased intracranial pressure, ICP crisis

SCOPE: Emergency evaluation and management of elevated intracranial pressure in adults. Covers recognition of elevated ICP (Cushing triad, papilledema, declining GCS), emergent interventions (osmotherapy, hyperventilation, sedation, CSF drainage), ICP monitoring indications, surgical decompression, and specific etiology-based management. Includes management across etiologies: traumatic brain injury, stroke (ischemic/hemorrhagic), tumor, infection, hydrocephalus, and idiopathic intracranial hypertension. Excludes pediatric ICP management (different thresholds/approaches).


PRIORITY KEY: STAT = Immediate | URGENT = Within hours | ROUTINE = Standard | EXT = Extended/atypical cases | - = Not applicable to this setting

═══════════════════════════════════════════════════════════════ SECTION A: ACTION ITEMS ═══════════════════════════════════════════════════════════════

1. LABORATORY WORKUP

1A. Essential/Core Labs

Test ED HOSP OPD ICU Rationale Target Finding
CBC with differential (CPT 85025) STAT STAT ROUTINE STAT Infection workup; anemia (reduced O2 carrying capacity); thrombocytopenia (bleeding risk); baseline Normal; leukocytosis → infection; thrombocytopenia → hemorrhage risk
CMP (BMP + LFTs) (CPT 80053) STAT STAT ROUTINE STAT Electrolytes (sodium critical for osmotherapy); renal function (contrast, mannitol); glucose; hepatic function Normal; track sodium closely (goal varies by treatment); avoid hyponatremia
Blood glucose (CPT 82947) STAT STAT ROUTINE STAT Hyperglycemia worsens outcomes in brain injury; hypoglycemia mimics neurologic deterioration 140-180 mg/dL target in critically ill; <180 in general
PT/INR (CPT 85610), aPTT (CPT 85730) STAT STAT - STAT Coagulopathy (hemorrhagic causes); ICP monitor placement safety; surgical candidacy Normal; INR <1.4 for ICP monitor placement
Serum osmolality (CPT 83930) STAT STAT - STAT CRITICAL for osmotherapy monitoring; baseline before mannitol/hypertonic saline; target for therapy 280-295 mOsm/kg baseline; therapeutic target 300-320 (do not exceed 320)
Sodium STAT STAT - STAT CRITICAL; hypertonic saline therapy monitoring; cerebral salt wasting vs. SIADH; target for ICP management 135-145 mEq/L baseline; therapeutic hypernatremia target 145-155 mEq/L (with hypertonic saline)
Arterial blood gas (ABG) (CPT 82803) STAT STAT - STAT Ventilation status (PaCO2 critical for ICP); oxygenation; pH; metabolic status PaCO2 35-40 mmHg (normal); pH 7.35-7.45; PaO2 >80; for hyperventilation: target PaCO2 30-35
Lactate (CPT 83605) STAT STAT - STAT Tissue perfusion; systemic sepsis; prognostic <2 mmol/L; elevated → hypoperfusion, sepsis
Type and screen (CPT 86900) STAT STAT - STAT Surgical candidacy; potential for decompressive craniectomy or other neurosurgical intervention On file
Troponin (CPT 84484) STAT STAT - STAT Neurogenic cardiac injury (stress cardiomyopathy); particularly in SAH, TBI, ICH Normal; elevated → neurogenic stress cardiomyopathy; obtain echo

1B. Extended Workup (Second-line)

Test ED HOSP OPD ICU Rationale Target Finding
Serum osmolality (serial) - STAT - STAT q4-6h during osmotherapy; osmolar gap calculation; prevent hyper-osmolar state Maintain <320 mOsm/kg; osmolar gap >10-15 → accumulating mannitol
Sodium (serial) - STAT - STAT q2-6h during active ICP management; hypertonic saline monitoring; avoid rapid correction Target 145-155 mEq/L during active ICP crisis; avoid fluctuations >10 mEq/24h
Cortisol (AM, random) (CPT 82533) - ROUTINE ROUTINE ROUTINE Adrenal insufficiency (pituitary injury in TBI, tumor); steroid responsiveness in tumor edema >10 mcg/dL (AM); if low → cortisol stimulation test or empiric steroids
TSH (CPT 84443), free T4 (CPT 84439) - ROUTINE ROUTINE - Pituitary injury (TBI, tumor, surgery); hypothyroidism Normal
Ammonia (CPT 82140) STAT STAT - STAT Hepatic encephalopathy differential; can cause cerebral edema and elevated ICP <35 μmol/L; elevated → hepatic cause; lactulose, rifaximin
Toxicology screen (CPT 80307) STAT STAT - STAT Intoxication as cause of altered mental status; drug-induced cerebral edema (rare) Negative; specific toxin identification
CSF analysis (if LP/EVD performed) - STAT - STAT Infection (meningitis); malignancy (leptomeningeal disease); subarachnoid hemorrhage (xanthochromia); IIH (elevated OP with normal composition) Normal CSF composition with elevated opening pressure → IIH; abnormal composition → specific diagnosis

1C. Rare/Specialized (Refractory or Atypical)

Test ED HOSP OPD ICU Rationale Target Finding
CSF opening pressure (LP) - URGENT ROUTINE - IIH diagnosis: OP >25 cm H2O (obese patients >28 cm); therapeutic in IIH; NOT indicated if mass lesion or obstructive hydrocephalus IIH: OP >25 cm H2O with normal composition; if OP >40-50 → severe
Pentobarbital level - - - STAT If barbiturate coma induced for refractory ICP; therapeutic monitoring; guide dosing; monitor for toxicity Therapeutic: 30-50 mcg/mL (for burst suppression); higher may be needed
EEG (continuous) - STAT - STAT Monitor for burst suppression during barbiturate coma; detect subclinical seizures (common in brain injury); guide sedation titration Target: burst suppression pattern during barbiturate coma; no seizures
Jugular venous oxygen saturation (SjvO2) - - - EXT Advanced cerebral metabolism monitoring; guide CPP management; detect ischemia or hyperemia 55-75%; <55% = ischemia (increase CPP or reduce CMRO2); >75% = hyperemia
Brain tissue oxygen (PbtO2) - - - EXT Direct brain oxygenation monitoring; guide therapy in severe TBI; multimodal monitoring >20 mmHg; <15 mmHg = brain hypoxia → intervene
Cerebral microdialysis - - - EXT Research/specialized centers; metabolic monitoring; lactate:pyruvate ratio; glucose; glutamate Lactate:pyruvate ratio <40 (normal); elevated = metabolic crisis

2. DIAGNOSTIC IMAGING & STUDIES

2A. Essential/First-line

Study ED HOSP OPD ICU Timing Target Finding Contraindications
CT head without contrast (CPT 70450) STAT STAT - STAT Immediate — within minutes of suspected elevated ICP; before any intervention; determines etiology and guides treatment Mass lesion (tumor, hematoma); midline shift (>5mm = significant); hydrocephalus; cerebral edema (effaced sulci, compressed ventricles); herniation signs (uncal, tonsillar); cisternal effacement None for non-contrast CT; benefit always outweighs risk in emergency
CT angiography (CTA) head (CPT 70496) STAT STAT - STAT If vascular etiology suspected (SAH, venous sinus thrombosis, AVM); concurrent with non-contrast CT Aneurysm (SAH); venous sinus thrombosis (filling defect in dural sinuses); AVM; dissection Contrast allergy (premedicate if critical); renal impairment (benefit may outweigh risk)
CT venography (CTV) STAT STAT ROUTINE STAT If cerebral venous sinus thrombosis suspected (headache, papilledema, focal deficits, hypercoagulable state); can be done with CTA Filling defect in dural sinuses (transverse, sigmoid, sagittal); "empty delta sign" on contrast CT; cord sign Same as CTA
MRI brain with and without contrast (CPT 70553) URGENT URGENT ROUTINE URGENT When clinically stable; superior for tumor characterization, infection, posterior fossa; MRV for venous thrombosis; DWI for ischemia Tumor; abscess; encephalitis; venous sinus thrombosis; ischemic stroke; PRES; herniation; meningeal enhancement MRI-incompatible implants; hemodynamic instability
Chest X-ray (CPT 71046) STAT STAT - STAT ETT position confirmation; pulmonary complications (aspiration, ARDS); central line position ETT position; no pulmonary infiltrate; line position None

2B. Extended

Study ED HOSP OPD ICU Timing Target Finding Contraindications
MR venography (MRV) - URGENT ROUTINE URGENT Cerebral venous sinus thrombosis confirmation; if CTV equivocal; can be done without contrast (TOF technique) Venous sinus thrombosis; flow void absence Same as MRI
Transcranial Doppler (TCD) (CPT 93886) - URGENT - URGENT Non-invasive ICP estimation (pulsatility index); vasospasm detection (SAH); cerebral circulatory arrest (brain death) Pulsatility index >1.4 suggests elevated ICP; MCA velocities for vasospasm; reverberating flow = no cerebral circulation None; operator-dependent
Optic nerve sheath diameter (ONSD) ultrasound STAT STAT - STAT Bedside non-invasive ICP estimation; ONSD >5-5.5 mm suggests ICP >20 mmHg; useful when formal monitoring not available ONSD >5 mm (some use 5.5 mm) = elevated ICP Limited accuracy; operator-dependent; not a substitute for invasive monitoring
CT perfusion (CPT 0042T) - URGENT - URGENT Ischemic stroke workup; penumbra assessment; vasospasm evaluation Perfusion deficits; core vs. penumbra; vasospasm patterns Contrast requirements
Fundoscopic examination STAT STAT ROUTINE STAT Papilledema detection (takes hours-days to develop); retinal hemorrhages (Terson syndrome in SAH); IIH evaluation Papilledema (indicates chronically or subacutely elevated ICP); absent papilledema does NOT exclude acute ICP elevation; venous pulsations absent if ICP >180 mm H2O None
Formal visual field testing - - ROUTINE - IIH monitoring; chronic elevated ICP; document visual field loss for treatment decisions Enlarged blind spot; peripheral constriction; nasal field loss Patient cooperation required

2C. Rare/Advanced

Study ED HOSP OPD ICU Timing Target Finding Contraindications
ICP monitor placement (invasive) - STAT - STAT Gold standard for ICP measurement; indications: GCS ≤8 with abnormal CT, or GCS ≤8 with normal CT + 2 of (age >40, SBP <90, motor posturing); also for hydrocephalus management; typically EVD or parenchymal monitor Direct ICP measurement; normal <15 mmHg; elevated >20-22 mmHg; treatment threshold >22 mmHg (Brain Trauma Foundation 2016) Coagulopathy (correct first); infection at insertion site; uncontrolled bleeding diathesis
External ventricular drain (EVD) - STAT - STAT ICP monitoring + therapeutic CSF drainage; preferred in hydrocephalus; allows ICP waveform analysis ICP measurement; CSF drainage; waveform analysis (P2 > P1 = decreased compliance) Same as ICP monitor
Continuous EEG monitoring (CPT 95700) - STAT - STAT Detect subclinical seizures (common in TBI, ICH, SAH — up to 20-30%); guide sedation; burst suppression monitoring during barbiturate coma No seizures; appropriate sedation level; burst suppression if pentobarbital coma None; resource availability
Nuclear medicine cerebral perfusion (SPECT/HMPAO) - - - EXT Brain death confirmation (ancillary test); no cerebral blood flow No uptake = brain death (if clinical criteria met and confounders excluded) Limited availability
CT/MRI perfusion for brain death - - - EXT Brain death confirmation; no cerebral perfusion No perfusion = brain death Same as standard CT/MRI

Lumbar Puncture

Study ED HOSP OPD ICU Timing Target Finding Contraindications
LP with opening pressure (CPT 62270) - URGENT ROUTINE - IIH diagnosis and treatment: measure opening pressure → therapeutic CSF removal; CONTRAINDICATED if mass lesion, obstructive hydrocephalus, or herniation risk; imaging FIRST Opening pressure: normal <20 cm H2O (obese <25); IIH: >25 cm H2O with normal CSF composition; high-volume tap (20-30 mL) for symptomatic relief in IIH ABSOLUTE CONTRAINDICATION: Mass lesion with mass effect; obstructive hydrocephalus; impending herniation; posterior fossa mass; midline shift; anticoagulation/coagulopathy; skin infection at LP site

3. TREATMENT PROTOCOLS

3A. Acute/Emergent Treatment

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
Airway management / Intubation IV - 0.3 mg/kg :: IV :: - :: GCS ≤8: Secure airway; RSI with agents that do NOT raise ICP; preferred: etomidate 0.3 mg/kg OR propofol 1-2 mg/kg + rocuronium 1.2 mg/kg OR succinylcholine 1.5 mg/kg; AVOID ketamine in severe TBI (controversial — emerging data suggest may be safe); lidocaine 1.5 mg/kg IV 2-3 min before laryngoscopy (may blunt ICP spike — controversial benefit); avoid hypotension during RSI - Airway protection; ventilation control (PaCO2 management); GCS ≤8 cannot protect airway; avoid hypoxia (PaO2 <60) and hypotension (SBP <90) — both worsen outcomes STAT STAT - STAT
Head of bed elevation - - N/A :: - :: continuous :: Elevate HOB 30°; neutral head position (avoid neck flexion/rotation that impedes jugular venous drainage); avoid tight cervical collar if possible; reverse Trendelenburg if cervical spine immobilization required - Promotes venous drainage; reduces ICP by 3-5 mmHg; no evidence of reduced CPP with 30° elevation; simple and immediate intervention STAT STAT - STAT
Hyperventilation (temporary) - - N/A :: - :: per protocol :: Acute herniation ONLY (bridging therapy); target PaCO2 30-35 mmHg; induces cerebral vasoconstriction → reduced cerebral blood volume → reduced ICP; Duration: <30 minutes ideally, maximum 2-4 hours; taper gradually; avoid PaCO2 <25 (causes ischemia) - BTF Guidelines: Avoid prophylactic hyperventilation; use only for acute ICP crisis/herniation as bridge to definitive therapy; prolonged hyperventilation causes rebound vasodilation and ischemia; monitor with SjvO2 or PbtO2 if prolonged use needed STAT STAT - STAT
Osmotherapy — Mannitol IV - 1-1.5 g/kg :: IV :: PRN :: Mannitol 20%: 1-1.5 g/kg IV bolus (e.g., 100g = 500 mL of 20% for 70 kg patient) over 15-20 minutes; repeat doses: 0.25-0.5 g/kg q4-6h PRN; Hold if: serum osmolality >320 mOsm/kg, osmolar gap >15-20; Requires: Foley catheter (massive diuresis); volume replacement; Onset: 15-30 min; Duration: 2-6 hours - Creates osmotic gradient → draws water from brain parenchyma; reduces brain volume; also improves blood rheology; BTF: Level II evidence; monitor for renal toxicity (ATN), hypovolemia, rebound edema STAT STAT - STAT
Osmotherapy — Hypertonic Saline IV - 30 mL :: IV :: Continuous :: 23.4% NaCl: 30 mL IV bolus over 15-20 min via central line (preferred for acute crisis); 3% NaCl: 250-500 mL IV bolus over 30 min (can give peripherally); Continuous infusion: 3% NaCl at 30-50 mL/hr to maintain Na 145-155 mEq/L; Target sodium: 145-155 mEq/L; avoid >160; correct slowly if hypernatremia develops (no faster than 8-10 mEq/24h decrease) - Equivalent or superior to mannitol for ICP reduction; does NOT cause diuresis (better for hypovolemic patients); no osmolality ceiling (unlike mannitol); does not accumulate in injured brain (mannitol may); preferred in many centers; SAFE-TBI trial (2021): 20% mannitol = HTS for ICP control STAT STAT - STAT
Sedation and analgesia - - 25-75 mcg/kg :: - :: - :: Goal: Reduce metabolic demand, prevent agitation-induced ICP spikes; Propofol: 25-75 mcg/kg/min (first-line; reduces CMRO2 and ICP; allows rapid awakening for neuro exams); Fentanyl: 25-100 mcg/hr (analgesia without histamine release); Midazolam: 0.05-0.2 mg/kg/hr (alternative to propofol); Avoid: Ketamine in severe ICP (controversial); prolonged propofol (PRIS syndrome >48-72h at high doses) - Agitation, pain, coughing raise ICP; sedation reduces cerebral metabolic rate; propofol has favorable ICP properties; daily sedation holiday for neuro assessment if stable STAT STAT - STAT
Neuromuscular blockade IV - 0.1-0.2 mg/kg :: IV :: once :: For refractory ICP spikes with ventilator dyssynchrony, coughing, posturing; Cisatracurium 0.1-0.2 mg/kg bolus → 1-3 mcg/kg/min infusion (organ-independent metabolism); Rocuronium 0.6-1 mg/kg bolus → 0.6 mg/kg/hr; Requires: Concurrent sedation/analgesia; train-of-four monitoring; prevents detection of seizures (need cEEG) - Prevents ICP spikes from coughing, posturing; reduces intrathoracic pressure; use judiciously — obscures neuro exam and seizure detection; requires cEEG monitoring - STAT - STAT
Seizure prophylaxis / treatment IV - 1000-1500 mg :: IV :: q12h :: Prophylaxis (TBI): Levetiracetam 1000-1500 mg IV load → 500-1000 mg q12h x 7 days (BTF: early seizure prophylaxis x 7 days for severe TBI); Active seizure: Lorazepam 0.1 mg/kg (max 4 mg) → Levetiracetam 60 mg/kg load (max 4500 mg) OR fosphenytoin 20 mg PE/kg; Status epilepticus: Per SE protocol - Seizures dramatically increase CMRO2 and ICP; early seizures occur in 10-15% of severe TBI; prophylaxis beyond 7 days NOT recommended (does not prevent late epilepsy); levetiracetam preferred (no drug interactions, IV/PO equivalent) STAT STAT - STAT
Temperature control - - 650-1000 mg :: - :: - :: Avoid fever aggressively: fever increases CMRO2 by 10-13% per °C; target 36-37°C; acetaminophen 650-1000 mg q4-6h; cooling blankets; Therapeutic hypothermia: 32-35°C controversial; EUROTHERM (2015) showed harm from prophylactic hypothermia to 32-35°C in TBI; may use for refractory ICP as rescue - Fever worsens neurologic outcomes; aggressive normothermia is standard; therapeutic hypothermia is rescue therapy only (not prophylactic); if used: 32-35°C, avoid shivering (increases CMRO2), slow rewarming STAT STAT - STAT
Blood pressure / CPP management IV - N/A :: IV :: continuous :: Target CPP 60-70 mmHg (CPP = MAP - ICP); avoid CPP <60 (ischemia) and >70 (BTF: avoid aggressive CPP >70 due to ARDS risk); If hypotensive: IV fluids (isotonic crystalloid; avoid hypotonic fluids); vasopressors (norepinephrine first-line); If hypertensive with ICP crisis: Treat ICP first (osmotherapy, sedation); avoid precipitously lowering BP (reduces CPP) - CPP is the primary determinant of cerebral perfusion; BTF 2016: target CPP 60-70; lower threshold 60 mmHg; aggressive CPP >70 increases ARDS risk without outcome benefit; individualized based on autoregulation status STAT STAT - STAT

3B. Definitive/Targeted Treatment (Tier 2 — Moderate ICP Elevation)

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
ICP monitor / EVD placement - - N/A :: - :: once :: Indications (BTF 2016): GCS ≤8 + abnormal CT; OR GCS ≤8 + normal CT + ≥2 of: age >40, SBP <90, motor posturing; EVD preferred if: Hydrocephalus; need for CSF drainage; Parenchymal monitor if: No hydrocephalus; cannot drain CSF; Target ICP: <22 mmHg (BTF 2016); some centers use <20 - Invasive ICP monitoring guides therapy; EVD allows therapeutic CSF drainage; parenchymal monitors cannot drain; infection risk ~5-10%; ventriculostomy is both diagnostic and therapeutic - STAT - STAT
CSF drainage (via EVD) - - 5-10 mL :: - :: Continuous :: Continuous drainage: Set drain to maintain ICP <22 mmHg; drain 5-10 mL CSF if ICP spike; Intermittent drainage: Drain for ICP >22, then clamp to re-measure; Typical: Remove 5-20 mL for ICP crisis; Rate: Avoid draining >20 mL/hour (risk of over-drainage, collapse of ventricles, hemorrhage) - Immediate ICP reduction; removes volume (CSF) from closed cranial compartment; critical for hydrocephalus; risk: infection, hemorrhage, over-drainage - STAT - STAT
Repeat osmotherapy dosing - - 0.25-0.5 g/kg :: - :: PRN :: Scheduled or PRN osmotherapy based on ICP readings; Mannitol: 0.25-0.5 g/kg q4-6h; HTS 3%: 30 mL/hr continuous or 250 mL bolus PRN; Monitor: Serum osm q4-6h (hold mannitol if >320); serum Na q2-4h (target 145-155 with HTS) - Sustained osmotherapy for sustained ICP elevation; alternating mannitol and HTS may extend treatment window; monitor for accumulation - STAT - STAT
Decompressive craniectomy - - N/A :: - :: once :: Indications: Refractory ICP despite maximal medical therapy; malignant MCA stroke (large hemispheric infarct with edema); large ICH with mass effect; traumatic brain injury with refractory ICP; Timing: TBI: DECRA trial (2011) — early DC did not improve 6-mo outcomes but reduced ICP/ICU stay; RESCUEicp (2016) — late rescue DC improved survival but increased severe disability; Stroke: DESTINY/DECIMAL/HAMLET — DC improves survival in malignant MCA stroke age <60 (NNT=2); must discuss goals of care - Removes skull to allow brain expansion; definitive ICP reduction; increases survival but may increase proportion surviving with severe disability; requires extensive goals of care discussion; timing and patient selection critical - STAT - -
Dexamethasone (tumor/vasogenic edema) IV - 10 mg :: IV :: q6h :: ONLY for vasogenic edema from tumor or abscess; NOT for TBI, stroke, or cytotoxic edema (steroids worsen outcomes in TBI — CRASH trial); Dose: 10 mg IV load → 4 mg IV q6h; Duration: Until definitive tumor treatment; taper over 1-2 weeks after radiation/surgery; GI prophylaxis with PPI - Reduces vasogenic edema around tumors; inhibits VEGF; dramatic effect within 24-48h; CRASH trial: steroids HARMFUL in TBI — avoid; no benefit in stroke - STAT ROUTINE STAT
Surgical evacuation of mass lesion - - 30 mL :: - :: - :: Epidural hematoma: Emergent if >30 mL, >15mm thickness, or >5mm midline shift, or GCS deterioration; Subdural hematoma: Emergent if >10mm thickness, >5mm midline shift, or GCS decrease >2 points; ICH: Consider if lobar >30 mL and deteriorating; cerebellar >3cm or hydrocephalus; Tumor: Resection or debulking for mass effect - Removes compressive mass → immediate ICP reduction; life-saving for epidural hematoma; subdural and ICH outcomes less clearly improved by surgery but indicated for mass effect and herniation - STAT - -

3C. Refractory ICP Management (Tier 3 — Rescue Therapies)

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
Pentobarbital coma IV - 5-10 mg/kg :: IV :: Continuous :: LAST RESORT for refractory ICP; Protocol: Pentobarbital 5-10 mg/kg IV load over 30 min → 1-3 mg/kg/hr infusion; titrate to ICP <22 mmHg or burst suppression on EEG; Target: Burst suppression (3-10 second bursts with 10-20 second suppression); Monitor: Continuous EEG; drug levels (30-50 mcg/mL); hemodynamics (causes hypotension — often need vasopressors); Duration: 24-48h then attempt to wean; may need 3-5 days - Reduces CMRO2 to minimal levels; dramatic ICP reduction; causes severe hypotension (need vasopressors); immunosuppression; ileus; prolonged sedation; no proven mortality benefit but reduces ICP; requires ICU expertise - - - STAT
Therapeutic hypothermia (rescue) - - N/A :: - :: per protocol :: For refractory ICP only (NOT prophylactic); Target: 32-35°C; Method: Surface cooling (Arctic Sun) or intravascular cooling catheter; Duration: 24-72h; Rewarming: Slow — 0.25°C/hour (rapid rewarming causes ICP rebound); Complications: Shivering (treat with paralysis, buspirone, meperidine), coagulopathy, infection, arrhythmia - Reduces CMRO2 and ICP; EUROTHERM (2015): prophylactic hypothermia HARMFUL in TBI; rescue hypothermia for refractory ICP still used but evidence weak; prevents fever spikes; requires expertise - - - STAT
Lumbar CSF drainage - - 5-10 mL/h :: - :: - :: ONLY if: Communicating hydrocephalus; ICP refractory to EVD drainage; no mass lesion or obstructive hydrocephalus; basal cisterns visible; Method: Lumbar drain at 10-15 cm H2O; drain 5-10 mL/hour; Risk: Tonsillar herniation if used inappropriately; overdrainage - Drains CSF from lumbar space; reduces overall CSF volume; effective adjunct in communicating hydrocephalus; must NOT be used with obstructive hydrocephalus or significant mass effect - - - STAT
High-dose hypertonic saline (23.4%) IV - 30 mL :: IV :: once :: For refractory ICP crisis; 30 mL IV bolus via central line; can repeat; target sodium up to 155-160 mEq/L in refractory cases (with close monitoring); Risk: Central pontine myelinolysis if rapid sodium changes (maintain stable elevated sodium; do not rapidly correct back to normal) - Potent osmotherapy; can achieve higher sodium targets than 3% NaCl; reserved for refractory cases; requires central line access - - - STAT
Decompressive craniectomy (rescue) - - 26.9% :: - :: - :: As above; indicated for refractory ICP after failure of all medical therapies; must discuss survival with potential severe disability (RESCUEicp: DC improved survival from 26.9% to 48.9% but increased severe disability); goals of care critical - RESCUEicp (2016): More patients survived with DC but at cost of more survivors with severe disability; DECRA (2011): Early prophylactic DC did not improve functional outcomes; decision requires extensive patient/family discussion - STAT - -

3D. Etiology-Specific Management

Etiology Specific Treatment
Traumatic Brain Injury (TBI) ICP monitoring if GCS ≤8; CPP 60-70; avoid hypoxia (PaO2 <60), hypotension (SBP <90), hyperventilation (except acute herniation), hyperglycemia (>180), hyperthermia; seizure prophylaxis x 7 days; surgical evacuation of hematomas per criteria; decompressive craniectomy for refractory ICP
Malignant MCA Stroke Decompressive craniectomy (hemicraniectomy) if age <60, within 48h; DESTINY/DECIMAL/HAMLET: NNT=2 for survival; discuss functional outcomes (many survive with hemiplegia, aphasia); no benefit from steroids; osmotherapy as bridge
Intracerebral Hemorrhage (ICH) BP control (target SBP <140 per INTERACT2/ATACH-2); reverse anticoagulation; surgical evacuation if cerebellar >3cm, lobar >30mL with deterioration; EVD for hydrocephalus; no steroids
Subarachnoid Hemorrhage (SAH) Secure aneurysm (clip/coil); nimodipine 60 mg q4h x 21 days; EVD for hydrocephalus; monitor for vasospasm (TCD, clinical); treat vasospasm (induced hypertension, intra-arterial therapy); euvolemia; avoid hypotension
Brain Tumor Dexamethasone 10 mg IV then 4 mg q6h (for vasogenic edema); PPI while on steroids; surgical resection/debulking for mass effect; radiation/chemotherapy as appropriate; no osmotherapy needed if steroids effective
Brain Abscess Antibiotics (empiric then targeted); surgical drainage (aspiration or excision) if >2.5 cm or refractory; dexamethasone for edema (controversial — may impair antibiotic penetration and immune response but used for severe edema); treat source
Meningitis Antibiotics (empiric then targeted); dexamethasone 0.15 mg/kg q6h x 4 days for bacterial meningitis (give before or with first antibiotic dose — reduces inflammation); ICP management as above; EVD for hydrocephalus
Hydrocephalus EVD (emergent temporizing measure); VP shunt (definitive for communicating); ETV (endoscopic third ventriculostomy for obstructive); treat underlying cause (tumor, hemorrhage, infection)
Idiopathic Intracranial Hypertension (IIH) Weight loss (most important long-term intervention); acetazolamide 250 mg BID → titrate to 1-2 g/day (reduces CSF production); topiramate (weight loss + ICP reduction); furosemide (adjunct); serial LP (therapeutic drainage); optic nerve sheath fenestration (for vision loss); VP shunt or transverse sinus stenting (refractory)
Cerebral Venous Sinus Thrombosis (CVST) Anticoagulation (heparin → warfarin or DOAC) even if hemorrhagic; ICP management as above; treat underlying hypercoagulable state; endovascular thrombectomy for refractory cases
Hepatic Encephalopathy / Acute Liver Failure Lactulose; rifaximin; treat precipitant; avoid sedatives; ICP monitoring in acute liver failure (cerebral edema common); mannitol; moderate hypothermia (33-34°C); liver transplant evaluation

3E. Medications to AVOID

Treatment Route Indication Dosing Contraindications Monitoring ED HOSP OPD ICU
Corticosteroids in TBI - - - - - - - - -
Corticosteroids in ischemic stroke - - - - - - - - -
Hypotonic fluids (D5W, 0.45% NaCl) - - - - - - - - -
Prolonged aggressive hyperventilation - - - - - - - - -
Ketamine (traditionally) - - - - - - - - -
Nitroprusside - - - - - - - - -
Propofol infusion syndrome (prolonged high-dose propofol) - - - - - - - - -

4. OTHER RECOMMENDATIONS

4A. Essential

Recommendation ED HOSP OPD ICU Details
Neurosurgery consultation — EMERGENT STAT STAT - STAT All patients with elevated ICP need neurosurgical evaluation; ICP monitor/EVD placement; surgical decompression decisions; hematoma evacuation
Neuro-ICU admission - STAT - STAT All patients with elevated ICP requiring intervention should be in Neuro-ICU or equivalent; 24/7 neuro-trained nursing; ICP monitoring capability; rapid imaging access
Continuous ICP monitoring (invasive) - STAT - STAT If GCS ≤8 with abnormal CT; or GCS ≤8 with normal CT + risk factors; guides all ICP-directed therapy; allows CPP calculation
Continuous EtCO2 / frequent ABG - STAT - STAT Ventilated patients: EtCO2 monitoring (correlate with ABG); target PaCO2 35-40; avoid hyperventilation except for acute crisis
Serial neurologic examination STAT STAT - STAT q1-2h in unstable patients; pupil reactivity; GCS; motor response; detect early herniation; any decline → immediate intervention
HOB elevation 30° / midline head STAT STAT - STAT Simple intervention; promotes venous drainage; reduces ICP
Avoid Valsalva / ICP-raising maneuvers STAT STAT - STAT Prevent coughing during suctioning (pre-oxygenate, lidocaine); avoid tight cervical collar; avoid constipation; stool softeners
Normothermia STAT STAT - STAT Treat fever aggressively; acetaminophen; cooling; each °C fever increases CMRO2 10-13%
Euvolemia STAT STAT - STAT Avoid both hypovolemia (reduces CPP) and fluid overload (may worsen edema); isotonic fluids; monitor CVP/volume status

4B. Extended

Recommendation ED HOSP OPD ICU Details
Ophthalmology consultation - URGENT ROUTINE - Fundoscopy for papilledema; IIH management; visual field testing; optic nerve sheath fenestration evaluation
Neurology consultation - URGENT ROUTINE URGENT Seizure management; EEG interpretation; IIH management; stroke management
Physiatry / Rehabilitation - ROUTINE ROUTINE - Early rehab evaluation; prognosis; disposition planning
Palliative care / Ethics - ROUTINE ROUTINE ROUTINE Goals of care for poor prognosis patients; decompressive craniectomy discussions (survival vs. disability); brain death evaluation
Social work - ROUTINE ROUTINE - Family support; long-term care planning; financial resources
Clinical neurophysiology / EEG - STAT - STAT Continuous EEG for subclinical seizures; burst suppression monitoring; guide sedation

4C. Atypical/Refractory

Recommendation ED HOSP OPD ICU Details
Multimodal neuromonitoring - - - EXT PbtO2 (brain tissue oxygen); SjvO2 (jugular venous saturation); cerebral microdialysis; optimize individual patient physiology; research/specialized centers
Targeted temperature management - - - EXT 32-35°C for refractory ICP; slow rewarming; prevent fever; requires specialized cooling devices
Brain death evaluation - - - ROUTINE If clinical brain death suspected; formal evaluation protocol; apnea testing; ancillary tests if confounders present
VP shunt / CSF diversion (long-term) - ROUTINE ROUTINE - Definitive hydrocephalus management; IIH refractory to medical therapy; post-hemorrhagic hydrocephalus
Transverse sinus stenting (IIH) - - ROUTINE - For IIH with venous sinus stenosis; reduces ICP; emerging therapy; specialized centers

═══════════════════════════════════════════════════════════════ SECTION B: SUPPORTING INFORMATION ═══════════════════════════════════════════════════════════════

5. DIFFERENTIAL DIAGNOSIS

Causes of Elevated ICP

Category Etiologies Key Features
Traumatic Traumatic brain injury (TBI); epidural hematoma; subdural hematoma; contusions; diffuse axonal injury History of trauma; CT findings; mechanism of injury
Vascular Ischemic stroke (malignant edema); intracerebral hemorrhage; subarachnoid hemorrhage; cerebral venous sinus thrombosis Sudden onset; focal deficits; CT/MRI findings; angiography for vascular lesions
Neoplastic Primary brain tumor; metastatic disease; leptomeningeal carcinomatosis Subacute progressive; known cancer history; MRI with contrast
Infectious Meningitis; encephalitis; brain abscess; subdural empyema Fever; meningismus; CSF analysis; ring-enhancing lesion
Hydrocephalus Obstructive (tumor, hemorrhage, aqueductal stenosis); communicating (post-infectious, post-hemorrhagic); normal pressure hydrocephalus Ventricular enlargement on imaging; gait disturbance, dementia, incontinence (NPH triad)
Idiopathic Intracranial Hypertension (IIH) Pseudotumor cerebri Young obese women; headache; papilledema; pulsatile tinnitus; normal imaging; elevated OP on LP
Metabolic Hepatic encephalopathy; hypertensive encephalopathy (PRES); hyponatremia (cerebral edema); hypoxic-ischemic injury Metabolic derangement; toxic screen; liver function; blood pressure
Other High altitude cerebral edema (HACE); post-operative; radiation necrosis; posterior reversible encephalopathy syndrome (PRES) Exposure history; post-procedural; imaging pattern (PRES: posterior white matter edema)

Signs of Elevated ICP and Herniation

Sign Indication
Cushing Triad Hypertension, bradycardia, irregular respirations — LATE and ominous sign of severely elevated ICP; indicates impending herniation
Declining GCS Increasing ICP affecting reticular activating system
Pupil asymmetry (unilateral dilation) Uncal herniation — compression of CN III; IPSILATERAL to lesion; dilated, fixed, "blown" pupil; emergent intervention needed
Bilateral fixed pupils Late brainstem herniation; very poor prognosis
Posturing (decerebrate/decorticate) Decorticate (flexion): midbrain/diencephalon dysfunction; Decerebrate (extension): pons/midbrain dysfunction; indicates progression
Papilledema Chronically or subacutely elevated ICP (takes hours-days to develop); fundoscopy; absent papilledema does NOT exclude acutely elevated ICP
Headache (worse lying down, morning) Increased ICP in recumbent position; chronic elevated ICP
Nausea/vomiting (projectile) Brainstem compression; elevated ICP
CN VI palsy "False localizing sign"; elevated ICP causes CN VI stretch along clivus; bilateral possible

Herniation Syndromes

Syndrome Anatomic Lesion Clinical Features Emergency Action
Uncal (transtentorial) Temporal lobe mass Ipsilateral pupil dilation (CN III); contralateral hemiparesis; decreased LOC; then bilateral pupil dilation, decerebrate posturing Osmotherapy STAT; hyperventilation; emergent surgical decompression
Central (transtentorial) Bilateral supratentorial mass effect Bilateral small pupils → bilateral fixed midpoint → bilateral dilated; progressive decrease in LOC; Cheyne-Stokes → central hyperventilation → ataxic breathing Same as above; worse prognosis than uncal
Subfalcine (cingulate) Unilateral hemisphere mass Contralateral leg weakness (ACA compression); may progress to transtentorial herniation Osmotherapy; surgical decompression of mass
Tonsillar (cerebellar) Posterior fossa mass; severe supratentorial pressure Neck stiffness; decreased LOC → respiratory arrest (medullary compression); rapid deterioration EXTREME EMERGENCY; osmotherapy; emergent posterior fossa decompression; cardiopulmonary arrest imminent
Upward (cerebellar) Posterior fossa mass with relief of supratentorial pressure Pinpoint pupils; loss of upgaze; rapid coma Posterior fossa decompression; avoid LP

6. MONITORING PARAMETERS

Acute Phase Monitoring (ICU)

Parameter Frequency Target Action if Abnormal
ICP (if monitored) Continuous <22 mmHg (BTF 2016); some centers <20 Tiered therapy escalation (osmotherapy → sedation → CSF drainage → hyperventilation → DC)
CPP (MAP - ICP) Continuous (calculated) 60-70 mmHg If low: IV fluids, vasopressors; if high (>70) and ICP elevated: focus on ICP reduction
Neurologic exam (GCS, pupils, motor) q1h initially; q2-4h when stable Stable or improving Decline: STAT CT; escalate ICP therapy; surgical evaluation
Serum sodium q2-4h during active osmotherapy 135-155 mEq/L (target varies); avoid rapid changes Adjust osmotherapy; correct slowly if needed
Serum osmolality q4-6h during mannitol therapy <320 mOsm/kg (some use <315) Hold mannitol if >320; switch to HTS
ABG / PaCO2 q4-6h; more frequent if adjusting ventilation 35-40 mmHg (normocapnia); 30-35 only for acute crisis Adjust ventilator; avoid hyperventilation except for crisis
Temperature Continuous 36-37°C; strict normothermia Aggressive cooling; acetaminophen; treat infection source
Blood glucose q4-6h 140-180 mg/dL Insulin titration
Urine output Hourly 0.5-1 mL/kg/hr Assess volume status; diuresis from mannitol expected (replace losses)
Hemodynamics (MAP) Continuous MAP to maintain CPP 60-70 Vasopressors; volume

ICP Waveform Analysis

Waveform Interpretation
Normal waveform Three peaks: P1 (percussion) > P2 (tidal) > P3 (dicrotic); indicates normal intracranial compliance
Abnormal waveform P2 > P1 ("rounded" waveform) = decreased intracranial compliance; indicates elevated ICP even if absolute value normal
Lundberg A waves (plateau waves) Sustained ICP elevation to 50-100 mmHg for 5-20 min; indicates severely impaired compliance; ominous
Lundberg B waves Oscillating ICP 20-50 mmHg at 0.5-2/min; indicates impaired compliance; precursor to A waves
Lundberg C waves Oscillating ICP at 4-8/min; corresponds to arterial BP variations; normal

7. DISPOSITION CRITERIA

Admission Criteria

Level of Care Criteria
Neuro-ICU Any patient requiring ICP monitoring; GCS ≤8; signs of herniation; requiring osmotherapy, sedation, or mechanical ventilation for ICP; post-operative after decompressive craniectomy or hematoma evacuation; status epilepticus; hemodynamic instability
Step-down / Intermediate care Stable ICP; improving neurologically; EVD weaning; transitioning off invasive monitoring; stable post-operative
General neurology/neurosurgery floor Stable IIH on medical therapy; post-VP shunt; stable post-operative without ICP concerns

Discharge Criteria

Criterion Details
ICP normalized ICP consistently <15-20 mmHg without intervention; EVD clamped successfully x 24-48h
Neurologic stability Stable or improving neurologic exam; no new deficits; able to follow commands
Off ICP-lowering medications Or transitioned to stable outpatient regimen (e.g., acetazolamide for IIH)
EVD removed / VP shunt functioning CSF diversion resolved or definitive shunt placed
Seizure control No seizures; stable AED regimen
Able to mobilize safely PT/OT clearance; appropriate level of care for deficits
Follow-up arranged Neurosurgery (1-2 weeks); neurology (as appropriate); ophthalmology (IIH); rehabilitation

8. EVIDENCE & REFERENCES

Key Guidelines

Guideline Source Year Key Recommendation
Guidelines for the Management of Severe Traumatic Brain Injury Brain Trauma Foundation (BTF) 2016 (4th ed) ICP threshold 22 mmHg; CPP 60-70 mmHg; avoid prophylactic hyperventilation; avoid steroids; early seizure prophylaxis x 7 days
Malignant MCA Stroke Guidelines AHA/ASA 2019 Decompressive craniectomy recommended for patients age <60 with malignant MCA stroke within 48h; discuss goals of care
ICH Guidelines AHA/ASA 2022 BP target SBP <140 (intensive reduction); reversal of anticoagulation; surgery for cerebellar hemorrhage >3cm
SAH Guidelines AHA/ASA 2023 Secure aneurysm early; nimodipine; EVD for hydrocephalus; euvolemia; monitor/treat vasospasm
IIH Guidelines British Consensus Guidelines 2018 Weight loss; acetazolamide; serial LP; optic nerve fenestration for vision loss; VP shunt for refractory

Landmark Studies

Study Finding Impact
BTF Guidelines (2016) ICP threshold changed from 20 to 22 mmHg; CPP target 60-70 (avoid >70); Level IIA evidence for ICP monitoring improving outcomes Standard of care for TBI ICP management
CRASH Trial (2004) Corticosteroids HARMFUL in TBI — 14-day mortality increased (25.7% vs. 22.3%, RR 1.15); 6-month mortality increased Steroids absolutely contraindicated in TBI
DECRA Trial (2011) Early decompressive craniectomy (within 72h) for refractory ICP in TBI did NOT improve 6-month functional outcome (though reduced ICP and ICU stay) Questioned early prophylactic DC; did not stop DC but informed timing decisions
RESCUEicp Trial (2016) Late/rescue DC for refractory ICP in TBI improved survival (48.9% vs. 26.9%) but increased proportion with severe disability; similar rates of favorable outcome DC is life-saving but increases survival with disability; requires goals of care discussion
DESTINY/DECIMAL/HAMLET (pooled) DC for malignant MCA stroke <60 years within 48h reduces mortality (NNT=2); higher survival with moderate-severe disability (mRS 4); DC should be offered Standard of care for malignant MCA stroke in appropriate patients
EUROTHERM (2015) Prophylactic hypothermia (32-35°C) in TBI HARMFUL — worse outcomes; trial stopped early Hypothermia NOT recommended prophylactically; rescue use only for refractory ICP
INTERACT2 / ATACH-2 (ICH) Intensive BP lowering (SBP <140) safe in ICH; modest benefit in INTERACT2; no benefit in ATACH-2 SBP <140 within 6h is current recommendation for ICH
SAFE-TBI (2021) 20% mannitol vs. hypertonic saline (various concentrations): no significant difference in ICP control or outcomes Either osmotic agent acceptable; hypertonic saline may be preferred in hypovolemia

ICP and CPP Targets Summary

Parameter Target Evidence Level
ICP <22 mmHg BTF Level IIB
CPP 60-70 mmHg BTF Level IIB (avoid CPP <60; avoid >70 due to ARDS risk)
PaCO2 35-40 mmHg (normocapnia) BTF Level IIB
PaCO2 (hyperventilation crisis) 30-35 mmHg (brief, <30 min) BTF Level III
Temperature 36-37°C (normothermia) BTF Level IIB
Glucose 140-180 mg/dL General critical care consensus
SBP (avoid hypotension) >100 mmHg (or >110 for TBI age 50-69) BTF Level III

APPENDICES

Appendix A: Tiered ICP Management Algorithm

ELEVATED ICP SUSPECTED OR CONFIRMED
               │
    TIER 0: GENERAL MEASURES (all patients)
    • HOB 30°, midline head position
    • Avoid hyperthermia (target 36-37°C)
    • Avoid hypoxia (PaO2 >60), hypotension (SBP >90-100)
    • Adequate sedation and analgesia
    • Avoid constipation/Valsalva
    • Treat seizures
               │
    ICP >22 mmHg despite Tier 0?
               │
    TIER 1: FIRST-LINE MEDICAL THERAPY
    • CSF drainage via EVD (if available)
    • Osmotherapy: Mannitol 0.5-1 g/kg OR
                   HTS 3% 250mL or 23.4% 30mL
    • Ensure adequate sedation
    • Brief hyperventilation if acute crisis (PaCO2 30-35)
               │
    ICP >22 mmHg despite Tier 1?
               │
    TIER 2: ESCALATED THERAPY
    • Repeat osmotherapy dosing
    • Optimize CPP (vasopressors if needed)
    • Neuromuscular blockade
    • Moderate hyperventilation with monitoring (SjvO2 or PbtO2)
    • Consider surgical evacuation of mass lesion
               │
    ICP >22 mmHg despite Tier 2?
               │
    TIER 3: RESCUE THERAPY (discuss goals of care)
    • Pentobarbital coma (target burst suppression)
    • Therapeutic hypothermia (32-35°C)
    • Decompressive craniectomy
    • High-dose hypertonic saline (Na target 155-160)

Appendix B: Osmotherapy Quick Reference

Agent Dose Onset Duration Max Threshold Administration Monitoring
Mannitol 20% 1-1.5 g/kg bolus; 0.25-0.5 g/kg repeat 15-30 min 2-6 hr Serum osm >320 Peripheral or central IV; filter; warm Serum osm q4-6h; BMP q6h; Foley (massive diuresis)
HTS 23.4% 30 mL over 15-20 min 5-15 min 2-4 hr Na >160 (relative) Central line only Na q2-4h; avoid rapid Na changes
HTS 3% 250-500 mL bolus or 30-50 mL/hr continuous 15-30 min 2-4 hr Na >160 (relative) Peripheral OK (central preferred) Na q2-4h
HTS 2% 500-1000 mL bolus or continuous 30 min 2-4 hr Na >160 (relative) Peripheral OK Na q4-6h

Key differences: - Mannitol: Causes diuresis → may worsen hypovolemia; accumulates in brain with BBB disruption; renal toxicity with prolonged use; osmolar gap monitoring - Hypertonic saline: No diuresis → better for hypovolemic patients; no osmolar gap ceiling; does not accumulate in brain; no renal toxicity; requires Na monitoring

Appendix C: Herniation Emergency Protocol

SIGNS OF ACUTE HERNIATION
(Pupil dilation, posturing, Cushing triad, rapidly declining GCS)
                    │
    IMMEDIATE ACTIONS (within minutes):
    1. Call for help (neurosurgery STAT, airway team)
    2. HOB to 30° (or reverse Trendelenburg if C-spine)
    3. Hyperventilation if intubated: target PaCO2 30-35
       (bag at 20 breaths/min; avoid PaCO2 <25)
    4. Osmotherapy STAT:
       • Mannitol 1-1.5 g/kg IV push (100g = 500 mL of 20%)
         OR
       • 23.4% NaCl 30 mL IV via central line over 10-15 min
         OR
       • 3% NaCl 500 mL rapid infusion if no central access
    5. STAT CT head (if not already done)
    6. Prepare for emergent surgical intervention
                    │
    THESE ARE BRIDGE THERAPIES
    Definitive treatment = surgical decompression
    (hematoma evacuation, DC, tumor resection, EVD)

Appendix D: IIH (Pseudotumor Cerebri) Management

Intervention Details
Weight loss Most important long-term intervention; 5-10% weight loss can significantly reduce ICP; bariatric surgery in morbid obesity
Acetazolamide First-line medical therapy; 250 mg BID → titrate to 1-2 g/day (or max tolerated); carbonic anhydrase inhibitor reduces CSF production; side effects: paresthesias, fatigue, taste alteration, metabolic acidosis
Topiramate Alternative to acetazolamide; also promotes weight loss; 50-100 mg BID; cognitive side effects
Furosemide Adjunct to acetazolamide; 20-40 mg daily; less effective than acetazolamide alone
Serial LP Therapeutic CSF removal; 20-30 mL per session; temporary relief; bridge to definitive treatment
Optic nerve sheath fenestration Surgical; for progressive visual loss; protects optic nerve; may not reduce headache
VP shunt Definitive CSF diversion; for refractory ICP or disabling headaches; shunt revision rates high
Venous sinus stenting For patients with transverse sinus stenosis (common finding in IIH); emerging therapy; reduces ICP by improving venous outflow; specialized centers

Appendix E: Medications Affecting ICP

Increases ICP Decreases ICP
Ketamine (controversial — may be safe in controlled ventilation) Propofol
Volatile anesthetics (at high concentrations) Barbiturates (thiopental, pentobarbital)
Nitroprusside Etomidate
Succinylcholine (transient) Benzodiazepines (mild)
Hypercapnia Fentanyl, remifentanil
Hypoxia Mannitol, hypertonic saline
Fever Hypothermia
Seizures Neuromuscular blockers (by preventing ICP spikes from posturing/coughing)
Valsalva, coughing, straining Hyperventilation (transient — use with caution)

This template represents the initial build phase (Skill 1) and requires validation through the checker pipeline (Skills 2-6) before clinical deployment.