Altered Mental Status & Coma
Systematic emergency approach to the confused, stuporous, or comatose patient: rapid reversible fixes, metabolic vs toxic vs structural workup, and managing acute brain herniation.
Resuscitation Quick Ribbon (First 2 Minutes)
Bottom-Line Clinical Pearl
Altered Mental Status (AMS) is a presentation, not a diagnosis. The initial approach is to immediately secure the airway and rule out easily reversible causes: check fingerstick glucose (hypoglycemia), assess pupillary response and respirations for opioid toxidrome (naloxone), and check temperature. Do NOT give flumazenil routinely to comatose patients due to refractory withdrawal seizures. If GCS <= 8, intubate for airway protection after ruling out reversible metabolic triggers.
1. AEIOU-TIPS Diagnostic Framework for Coma
| Mnemonic Letter | Etiologies | Initial Diagnostic Test in ED |
|---|---|---|
| A - Alcohol / Acidosis | Intoxication, withdrawal (DTs), DKA, lactic acidosis | Blood alcohol level, BMP, venous blood gas, anion gap |
| E - Epilepsy / Encephalopathy | Status epilepticus, post-ictal state, hepatic/hypertensive | Bedside glucose, non-contrast CT head, STAT EEG, ammonia |
| I - Insulin / Infection | Severe hypoglycemia, sepsis, meningitis, encephalitis | Fingerstick glucose, blood cultures, lumbar puncture, chest X-ray |
| O - Opiates / Oxygen | Opioid overdose, severe hypoxia, carbon monoxide, hypercapnia | Pulse oximetry, ABG/VBG for pCO2, carboxyhemoglobin, trial naloxone |
| U - Uremia | Acute renal failure, uremic pericarditis/encephalopathy | BUN, Creatinine, electrolyte panel, urinalysis |
| T - Trauma / Toxin / Tumor | Epidural/subdural hematoma, concussion, toxic ingestion, mass | Non-contrast CT head, urine drug screen, acetaminophen/aspirin levels |
| I - Infection | Sepsis, central nervous system infection | Urinalysis, chest radiograph, lumbar puncture |
| P - Psych / Porphyria | Catatonia, conversion disorder, functional coma | Diagnosis of exclusion; normal pupillary/oculocephalic reflexes |
| S - Stroke / Shock | Ischemic stroke, basilar artery thrombosis, SAH, hypoperfusion | CTA head/neck, MRI brain with diffusion, lactate, cardiac monitor |
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