🧠 Chapter 31: Altered Mental Status

Nelson's Pediatric Symptom-Based Diagnosis | Coma · Delirium · Glasgow Coma Scale · Intracranial hypertension · Toxic/metabolic encephalopathy · Meningitis · Status epilepticus

🔍 Altered Mental Status in Children: Key Concepts

🧠 Definitions (GCS)
Coma: unarousable unresponsive. Delirium: acute fluctuating inattention. GCS (modified for children) 3-15. FOUR score includes brainstem reflexes.
🚩 Red Flags: ↑ICP
Cushing triad (hypertension, bradycardia, irregular respirations), papilledema, anisocoria, posturing (decorticate/decerebrate), CN VI palsy.
⚡ Emergent Management
ABCs, glucose, naloxone if opioid suspected. Treat hypoglycemia (D10W 2-4 mL/kg), sepsis, status epilepticus. Lumbar puncture after CT if mass suspected.
🧪 Toxic-Metabolic Causes
Hypoglycemia, DKA, hepatic encephalopathy (ammonia), uremia, inborn errors of metabolism (hyperammonemia, organic acidemias), poisoning (toxidromes).
🦠 Infectious Causes
Meningitis (fever, nuchal rigidity, bulging fontanel), encephalitis (altered mentation + seizures), brain abscess, sepsis.
🧠 Structural Causes
Traumatic brain injury, intracranial hemorrhage (subdural, epidural, subarachnoid), brain tumor, hydrocephalus, stroke, CNS vasculitis.

💡 Key takeaway: Altered mental status is a life-threatening emergency. Secure airway/breathing/circulation first. Rapidly assess for reversible causes (glucose, naloxone). Localize lesion (supratentorial vs brainstem) using pupils, eye movements, motor responses. CT before LP if focal deficits or papilledema.

🩺 Clinical Approach to Altered Mental Status in Children

🔹 Step 1: Stabilization (ABCs) and emergency interventions
• Secure airway, breathing, circulation. Obtain IV/IO access.
• STAT bedside glucose: if <60 mg/dL give D10W 2-4 mL/kg.
• Naloxone 0.1 mg/kg if opioid poisoning suspected.
• Treat ongoing seizures with benzodiazepines.
🔹 Step 2: Assess for signs of increased intracranial pressure (ICP)
• Cushing triad (hypertension + bradycardia + irregular respirations).
• Papilledema, unilateral dilated pupil (uncal herniation), CN VI palsy.
• Decorticate (hemispheric) or decerebrate (brainstem) posturing.
• If ↑ICP suspected: elevate HOB 30°, hyperventilate to PCO2 30-35, mannitol, neurosurgery consult.
🔹 Step 3: History and physical to narrow differential
• Fever + nuchal rigidity → meningitis (LP after CT if focal signs).
• Head trauma → CT to rule out bleed/contusion.
• Known diabetes → DKA or hypoglycemia.
• Toxidromes (pinpoint pupils → opioid; dilated + dry → anticholinergic; sweating + salivation → organophosphate).
• Inborn error of metabolism: recurrent episodes, acidosis, hyperammonemia.
🔹 Step 4: Neuroimaging and lumbar puncture
• Noncontrast CT head: rapid for hemorrhage, mass, hydrocephalus.
• MRI: better for stroke, encephalitis, demyelination.
• LP contraindications: signs of ↑ICP, focal deficits, coagulopathy. If needed, CT first.
• CSF: WBC, glucose, protein, culture, PCR (HSV, enterovirus).
🔹 Step 5: Laboratory evaluation for metabolic/toxic causes
• Electrolytes, BUN, creatinine, calcium, magnesium, phosphate.
• ABG/VBG, lactate, ammonia, liver enzymes.
• Urine toxicology, serum drug levels (acetaminophen, salicylate, anticonvulsants).
• Thyroid function, cortisol if adrenal insufficiency suspected.