Acute Agitation

1. THE 2-MINUTE PHYSIOLOGY (Rapid Pathophysiology)

• The Organic Brain Failure: Acute agitation is rarely a primary psychiatric event in the emergency department; it is a clinical manifestation of profound cellular distress in the brain. The underlying pathophysiology involves either a massive surge in excitatory neurotransmitters (e.g., dopamine, norepinephrine) or a critical depletion of inhibitory neurotransmitters (e.g., GABA) [External EM Knowledge].
• Cellular Starvation & Trauma: This neurotransmitter chaos is directly driven by life-threatening physiologic breakdowns, most notably profound hypoxia, low-flow states secondary to systemic hemorrhage, or direct mechanical disruption such as diffuse axonal injury and intracranial hemorrhage.
• Toxicologic & Metabolic Derangement: Toxins acting as sympathomimetics or anticholinergics trigger a hyper-adrenergic state, while alcohol or benzodiazepine withdrawal removes the brain's GABAergic "brakes," precipitating severe delirium and agitation. Systemic endocrine crises (like thyrotoxicosis/thyroid storm or profound hypoglycemia) similarly uncouple normal cerebral metabolism, presenting as abusive or combative behavior.

2. THE BEDSIDE ACTION PLAN (Rapid ER Management)

• Immediate Stabilization: The absolute first step in assessing a confused or agitated patient is securing basic physiological parameters: you must immediately obtain blood pressure, pulse oximetry, and a core temperature.
• The Glucose Check: A rapid bedside fingerstick glucose is mandatory to rule out profound hypoglycemia, which is an immediate, reversible cause of combative altered mental status.
• De-escalation & Restraint [External EM Knowledge]: Attempt verbal de-escalation first. If the patient poses an immediate physical threat to themselves or staff, proceed directly to rapid chemical restraint. Physical restraints should only be used as a temporary bridge to chemical restraint to prevent asphyxiation and rhabdomyolysis.
• Pharmacology (Chemical Restraint) [External EM Knowledge]:
• First-Line (Undifferentiated/Agitated): Midazolam 2–5 mg IM/IV or Haloperidol 5–10 mg IM/IV.
• Severe "Excited Delirium": Ketamine 4–5 mg/kg IM for rapid, definitive dissociation within 3-4 minutes.
• (Note: Specific chemical restraint dosages are supplied from standard external EM literature, as they are not explicitly listed in the provided source texts. Please independently verify.)

3. THE DIAGNOSTIC GRID (Differential Diagnosis & Workup)

Emergency clinicians must actively rule out organic pathology before considering a psychiatric etiology. The critical "can't-miss" differential diagnoses include:

• Toxicologic Crises: Acute alcohol intoxication, sympathomimetic intoxication, anticholinergic intoxication, delirium tremens, and withdrawal from alcohol, benzodiazepines, or narcotics.
• Endocrine & Metabolic: Hypoglycemia, severe hyperglycemia (DKA/HHS), and thyrotoxicosis/thyroid storm.
• Infectious Catastrophes: Meningitis, encephalitis, systemic sepsis, and severe urinary tract infections in the elderly.
• Traumatic & Hypoxic States: Intracranial hemorrhage, diffuse axonal injury, hypoxia, and low-flow states secondary to systemic hemorrhage.
• Prioritized Workup:

1. Point-of-care glucose, pulse oximetry, and temperature.
2. Basic metabolic panel, complete blood count, and tox screens.
3. Non-contrast CT Head to evaluate for traumatic bleeding or mass effect.

4. THE VISUAL BOARD (ECG / POCUS / Imaging)

• Standard ECG: You must look for occult cardiac signs of toxicity or ischemia. Specifically, evaluate for prolonged QTc intervals (>500 ms), bundle branch blocks, or new significant arrhythmias (e.g., ventricular tachycardia, bradycardia) which can precipitate cerebral hypoperfusion or indicate toxidromes.
• CT Head (Non-Contrast): Essential to rule out the traumatic causes of agitation. The resident must specifically look for intracranial hemorrhage (epidural, subdural, subarachnoid, or intraparenchymal) and signs of diffuse axonal injury.
• POCUS (eFAST/Echo): Utilize bedside ultrasound to look for occult systemic hemorrhage (eFAST) or poor cardiac contractility (Echo) that may be causing a low-flow hypoperfusion state presenting as agitation.

5. THE SCORING MATRIX (Risk Stratification & Guidelines)

• Richmond Agitation-Sedation Scale (RASS) [External EM Knowledge]: This is the gold-standard, validated tool used to risk-stratify the severity of agitation and titrate chemical restraint. Scores range from +4 (Combative, violent) to 0 (Alert and calm) down to -5 (Unarousable).
• ICU Agitation & Delirium Guidelines: Clinical practice guidelines dictate that the prevention and management of pain, agitation, and delirium must be strictly protocolized once the patient is stabilized and transferred to the ICU.
• ED Observation Unit Exclusions: Agitated patients who exhibit abnormal vital signs (HR <50 or >100, SBP <100 or >200, SpO2 <94%, RR >24) or who have a prolonged QTc (>500 ms) on their ECG strictly fail ED Clinical Decision Unit criteria and require higher-level admission.
• (Note: The exact RASS criteria matrix is provided via external EM standard knowledge for completeness. Please independently verify.)

6. THE DANGER ZONE (Pitfalls & Critical Actions)

• The "Psych Patient" Premature Closure: The most deadly cognitive trap in emergency medicine is premature closure. Emergency clinicians must actively avoid ascribing agitated or abusive behavior to drug/alcohol intoxication or an underlying psychiatric disorder without first completing a rigorous medical workup.
• Failure to Obtain Vitals: Skipping a full set of vital signs in a combative patient is a catastrophic error. You must obtain a blood pressure, temperature, and pulse oximetry reading to catch infectious or hypoxic drivers of the agitation.
• CRITICAL ACTION: Board examiners mandate that you verbalize checking a bedside blood glucose on any patient presenting with altered mental status or agitation before proceeding with further workup.

7. MCQ MASTERCLASS (Written Exam Tips)

• High-Yield Buzzword: If a board question describes a patient exhibiting "abusive," "combative," or "agitated" behavior, the question is almost certainly testing your ability to rule out organic medical disease.
• The Classic Distractor: The stem will heavily imply the patient is "drunk" or "crazy" (e.g., “A 45-year-old male with a known history of schizophrenia and alcohol abuse is yelling at nurses...”). The distractor options will be "Consult Psychiatry" or "Administer Haloperidol and send to the psych unit."
• The Correct Answer: The correct answer will always involve a medical screening action first—most commonly, "Check a fingerstick blood glucose," "Obtain a pulse oximetry reading," or "Perform a CT of the Head to rule out intracranial hemorrhage".

8. THE BOARDROOM SCRIPT (OSCE & Oral Board Tips)

• The Opening Salvo: "Examiner, this patient presents with severe, undifferentiated acute agitation. My immediate priority is the physical safety of the patient and my staff. I will attempt verbal de-escalation while simultaneously preparing for chemical restraint if required."
• The Medical Rule-Out: "I will not anchor on intoxication or psychiatric illness. I am immediately ordering a point-of-care blood glucose, placing the patient on a cardiac monitor, and obtaining a core temperature and pulse oximetry reading to rule out profound hypoxia, hypoglycemia, or thyrotoxicosis."
• The Handoff: "With the patient now chemically sedated and vitals stabilized, my differential diagnosis focuses on the organic causes of agitation: infectious, toxicologic, endocrine, and traumatic etiologies. I am ordering a non-contrast CT of the head to rule out intracranial hemorrhage, alongside a broad metabolic and toxicology panel."