What are the red flag symptoms and management of suspected increased intracranial pressure (ICP)?

Red Flag Symptoms and Management of Suspected Increased Intracranial Pressure (ICP)

Clinical assessment, not CT scan, should be the primary method to determine if a lumbar puncture is safe to perform in patients with suspected increased intracranial pressure (ICP). 1

Red Flag Symptoms of Increased ICP

Early Warning Signs

• Headache - especially when:
  • Worse in the morning or when lying flat
  • Exacerbated by Valsalva maneuvers (coughing, straining)
  • Progressive in severity or changing in character
  • Associated with nausea/vomiting
• Papilledema - a critical finding requiring immediate attention 2
• Nausea and vomiting - particularly projectile vomiting without preceding nausea
• Visual disturbances - including blurred vision, double vision, or visual field defects
• Altered mental status - ranging from subtle confusion to decreased consciousness

Late/Severe Signs (indicating critical ICP elevation)

• Cushing's triad - hypertension, bradycardia, and irregular breathing pattern 2
• Pupillary changes - sluggish, unequal, or fixed and dilated pupils
• Abnormal posturing - decorticate (flexion) or decerebrate (extension) posturing
• Decreased level of consciousness - progressing to stupor and coma 2
• Respiratory abnormalities - including Cheyne-Stokes respiration or central neurogenic hyperventilation
• Focal neurological deficits - including cranial nerve palsies, hemiparesis, or quadriparesis 2, 3

Management Algorithm for Suspected Increased ICP

Immediate Assessment and Stabilization

1. Position the patient with head and trunk elevated at 20-30 degrees (avoid elevation >30 degrees) 2
2. Secure airway if GCS <8 or deteriorating respiratory status
3. Assess need for immediate intervention based on clinical signs of herniation

Diagnostic Approach

1. Neuroimaging - CT or MRI should be performed as soon as possible 1

   • If clinical contraindications to lumbar puncture exist, CT should be performed first
   • MRI is preferred when available as it provides more detailed information about brain parenchyma

2. Lumbar puncture considerations:

   • Perform LP as soon as possible after hospital admission unless contraindicated 1
   • Contraindications to immediate LP:
     • Clinical signs of brain shift or raised ICP
     • Significant brain shift or tight basal cisterns on imaging
     • Coagulopathy or anticoagulation therapy (requires correction first)
     • Local infection at puncture site

Medical Management

1. First-line interventions:

   • Osmotic therapy - Mannitol 0.25-2 g/kg IV over 30-60 minutes 2, 4
     • For pediatric patients: 1-2 g/kg or 30-60 g/m² body surface area
     • For small or debilitated patients: 500 mg/kg
   • Ventilation management - maintain normocapnia (PaCO₂ 35-40 mmHg) 2
     • Short-term hyperventilation (PaCO₂ 25-30 mmHg) only for acute, life-threatening ICP elevations

2. Hemodynamic management:

   • Maintain cerebral perfusion pressure (CPP) >60-70 mmHg 2, 5
   • Avoid hypotension to prevent secondary brain injury
   • Monitor blood pressure continuously in patients requiring IV antihypertensives

3. Additional measures:

   • Control seizures with appropriate antiepileptic therapy 2
   • Maintain normothermia and treat fever aggressively 2
   • Provide adequate sedation and analgesia to minimize pain and ICP increases 2

Surgical Management

1. CSF drainage - ventricular drainage for hydrocephalus 2
2. Decompressive craniectomy - for refractory intracranial hypertension 2, 6
3. Evacuation of mass lesions - for hematomas or tumors causing significant mass effect 2

Monitoring Parameters

• Target ICP <20-25 mmHg 2, 5
• Target CPP 60-70 mmHg 2
• Continuous monitoring of vital signs, neurological status, and electrolytes
• Reassess need for LP every 24 hours if initially contraindicated 1

Important Caveats

• Recognize that elderly patients may present atypically, making diagnosis more challenging 1
• Avoid concomitant administration of nephrotoxic drugs with osmotic agents like mannitol 4
• Be vigilant for fluid and electrolyte imbalances during osmotic therapy 2, 4
• CT scan is not a reliable tool for diagnosis of raised ICP and should not replace clinical assessment 1
• In children with sickle cell anemia, acute headache is more frequently associated with acute central nervous system events than in the general pediatric population 1