Neuro

Increased Intracranial Pressure in Closed Head Injury

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Increased Intracranial Pressure in Closed Head Injury, Increased Intracranial Pressure in Trauma, Severe Head Trauma Related Increased Intracranial Pressure, Neurocritical Intubation

  • Differential Diagnosis
  • Pathophysiology
  • Signs
  • Findings indicating management below
  1. Intracranial Pressure >15 mm
  2. Severe Closed Head Injury (GCS 8 or less)
  3. Cerebral edema
  4. Cushing Response
    1. Severe Hypertension
    2. Severe Bradycardia
    3. Severe Hypopnea
  1. Indications
    1. Glasgow Coma Scale 8 or less after Resuscitation (or <12 if abnormal CT Head) OR
    2. Criteria despite normal CT Head
      1. Age >40 years old
      2. Systolic Blood Pressure <90 mmHg
      3. Decerebrate or Decorticate motor posturing (unilateral or bilateral)
  • Management
  1. See Severe Head Injury Management
  2. Transfer to Neurosurgery
  3. See Cerebral Herniation
  4. Improve cerebral venous drainage
    1. Head of bed elevated (20-35 degrees, up to 45 degrees)
      1. Promotes CNS venous drainage
    2. Avoid internal jugular compression
      1. Keep head midline
      2. Internal jugular line placement is Contraversial (some advocate subclavian lines instead)
      3. Avoid tight Cervical Collars
        1. Switch to better fitting collar (e.g. Aspen) if C-spine cannot be cleared with exam and imaging
  5. Maintain adequate Cerebral Perfusion Pressure (MAP - ICP)
    1. Maintain MAP>65-80 mmHg (and ideally ICP <20)
    2. Keep systolic Blood Pressure <140-160 mmHg (higher BPs raise Intracranial Pressure)
      1. Nicardipine (or Clevidipine) is preferred
      2. Avoid Nitroglycerin and Nitroprusside (if possible) to maintain adequate Preload
      3. Avoid Labetalol (if possible) to maintain adequate cardiac contractility
  6. Acutely lowering Intracranial Pressure (e.g. impending Brainstem Herniation)
    1. Mannitol 20%
      1. Adult: 1 g/kg IV (50-100 g) bolus over 5 minutes
      2. Child: 0.25 to 0.5 g/kg IV bolus over 5 minutes
      3. Observe closely for Hypotension, especially peri-intubation (and avoid if hypotensive)
      4. Monitor Urine Output
      5. Hold manitol for Hypotension, Hypernatremia with Sodium >152 or Serum Osms >305
    2. Other measures to consider
      1. Phenobarbital Infusion
        1. Mansour (2013) J Neurosurg Pediatr 12(1):37-43 [PubMed]
      2. Hypertonic Saline (controversial)
        1. Dosing: 100 cc of 3% Saline
        2. Does not improve Intracranial Pressure or benefit mortality in Severe Closed Head Injury
          1. Berger-Pelleiter (2016) CJEM 18(2): 112-20 +PMID:26988719 [PubMed]
        3. Others still recommend Hypertonic Saline (consider for signs Brainstem Herniation)
          1. Expert opinion that Hypertonic Saline and manitol have equivalent efficacy
          2. Hypertonic Saline is safe, even in Hyponatremia, and without Hypotension risk
          3. Orman and Weingart in Herbert (2017) EM:Rap 17(6):8-9
    3. Other measures that are no longer recommended (debunked)
      1. Avoid Hyperventilation (see above)
  7. Definitive management with Neurosurgery
    1. See Skull Trephination (if imminent Brainstem Herniation)
    2. Ventriculostomy or
    3. Surgical decompression
  • Management
  • Neurocritical Intubation
  1. Indications
    1. Follow emergent airway management protocols instead for patient presenting obtunded (e.g. GCS<=8) after Head Trauma
      1. Do not delay intubation if indicated on presentation
    2. Advanced Airway Management in a patient deteriorating due to Increased Intracranial Pressure (and risk of Brainstem Herniation)
      1. Subarachnoid Hemorrhage
      2. Hemorrhagic CVA
  2. Airway and Rapid Sequence Intubation Management
    1. Optimize Blood Pressure control prior to intubation (systolic Blood Pressure <140 mmHg)
      1. Nicardipine (or Clevidipine) is preferred (see above)
      2. Have medications ready for administration should Blood Pressure spike during Endotracheal Intubation
        1. Nicardipine 0.25 mg IV bolus could be given while preparing infusion
      3. Also be prepared for Hypotension following intubation
        1. Push Dose Epinephrine could be considered
    2. Avoid peri-intubation Hypoxia
      1. Maximize Intubation Preoxygenation
      2. Consider Delayed Sequence Intubation
    3. Avoid mechanical, noxious airway stimulation (risk of spiking Intracranial Pressure)
      1. Avoid excessive pressure on posterior pharynx
      2. Video Laryngoscopy is preferred (less pressure on posterior pharynx)
      3. Most skilled intubator should perform the Endotracheal Intubation
        1. Prolonged and repeated intubation attempts are associated with Increased Intracranial Pressure
    4. Premedications are not typically indicated (but may consider Fentanyl)
      1. Pre-Intubation Lidocaine has been debunked and offers no benefit in ICP (see Rapid Sequence Intubation)
      2. Fentanyl
        1. Dose: 4-5 mcg/kg given at least 5 minutes before intubation
        2. Blunts Catecholamine response and may decrease Intracranial Pressure (ICP)
        3. However, risk of apnea and Hypotension (be prepared for supportive care)
    5. Induction
      1. Etomidate is a preferred RSI induction agent in Head Injury
      2. Ketamine is a safe and effective RSI induction agent without risk of ICP increase
        1. May consider Ketamine in combination with Propofol known as ketofol (e.g. 75:50 or 50:50 Propofol:Ketamine)
        2. Zeiler (2014) J Crit Care 29(6): 1096-106 +PMID:24996763 [PubMed]
        3. Cohen (2015) Ann Emerg Med 65(1): 43-51 +PMID:25064742 [PubMed]
    6. Paralytic Agent
      1. Preferred paralytic: Rocuronium
        1. Unlike Succinylcholine, does not cause Fasciculations (which may in turn cause increased ICP)
  3. Post-Intubation: Sedation and Analgesia
    1. Start sedation and analgesia immediately after intubation (prepare infusions before intubation, ready for use)
    2. Analgesia: Fentanyl infusion
    3. Sedation: Propofol
      1. Propofol may be preferred (lowers cerebral metabolic rate)
      2. Start Propofol at 20 mcg/kg/min and titrate
      3. Limit Propofol boluses as much as possible to avoid Blood Pressure fluctuations
        1. If boluses are needed, use small, 20 mg IV boluses at a time
  4. Ventilation
    1. Follow Lung Protective Ventilator Strategy
      1. Tidal Volume 6-8 ml/kg IBW
      2. Respiratory Rate 16/min
      3. PEEP and FIO2 combinations (via PEEP Table) to maintain Oxygen Saturation targets (see below)
        1. PEEP does not increase intracranial presssure (increase as needed)
    2. Avoid hyperoxygenation
      1. Goal Oxygen Saturation >90-93% and preferred at 94-97%
    3. Avoid Hyperventilation
      1. Use Blood Gas to guide adjustments
      2. Normocapnia is preferred (pCO2 35 to 38 mmHg)
        1. Increase Respiratory Rate only for pCO2 >35 to 38 mmHg
      3. Hyperventilation is generally no longer recommended
        1. Vasoconstricts (reducing ICP transiently) but also decreasing cerebral perfusion
        2. Some intensivists mildly hyperventilate with goal pCO2 30-35 mmHg
        3. Old guidelines hyperventilated to pCO2 25-30 mmHg
  • Precautions
  1. Sustained ICP > 20 mmHg is associated with worse outcomes (ischemia risk)
  2. Maintain adequate Cerebral Perfusion Pressure
  • References
  1. Orman and Weingart in Herbert (2017) EM:Rap 17(1): 5-6
  2. Swaminathan and Weingart in Swadron (2022) EM:Rap 22(10): 5-7