A 48-year-old woman with a 20-year history of alcohol dependence is admitted to hospital after a motor vehicle accident. She sustained a fractured tibia and is scheduled for surgical fixation. On day 2 post-admission, she becomes increasingly restless, diaphoretic, and confused. Temperature is 38.5°C, heart rate 128/min, blood pressure 162/104 mmHg, and respiratory rate 24/min. She reports visual hallucinations of insects crawling on her skin. Her last documented alcohol intake was 36 hours before admission. Which of the following is the most likely diagnosis and the best immediate management?

Explanation

## Clinical Diagnosis: Delirium Tremens (DTs) ### Diagnostic Criteria Recognition The patient presents with the **classic tetrad of delirium tremens**: | Feature | Present in This Case | |---------|----------------------| | **Autonomic hyperactivity** | HR 128, BP 162/104, fever 38.5°C, diaphoresis | | **Visual/tactile hallucinations** | Insects crawling on skin (tactile) | | **Disorientation & confusion** | Acute mental status change | | **Tremor** | Implied by restlessness; often present | | **Timing** | 36 hours post-last drink (peak onset 48–96 hrs) | **High-Yield:** DTs is the **most severe form of alcohol withdrawal** and represents a medical emergency with mortality of 15–20% if untreated. ### Pathophysiology 1. **Chronic alcohol** → chronic GABA~A~ receptor downregulation and glutamate upregulation 2. **Abrupt cessation** → loss of GABA inhibition + unopposed glutamate excitation 3. **Result:** Severe CNS hyperexcitability, autonomic storm, and hallucinations **Key Point:** The hallucinations in DTs are typically **visual or tactile** (not auditory), and patients retain insight that they are hallucinations (unlike psychosis). The fever is due to hypermetabolism and sympathetic overdrive, not infection. ### Immediate Management Algorithm ```mermaid flowchart TD A["Suspected Delirium Tremens<br/>(Autonomic + Hallucinations + Confusion<br/>36-96 hrs post-cessation)"]:::outcome A --> B{"Confirm diagnosis<br/>& rule out mimics"}:::decision B -->|"Vital signs, mental status,<br/>labs (glucose, Mg, Ca, PO4),<br/>CT head if trauma history"| C["Confirmed DTs"]:::outcome C --> D["Lorazepam 2-4 mg IV<br/>q 5-10 min until calm<br/>+ Thiamine 100 mg IV"]:::action D --> E["ICU admission<br/>Continuous monitoring"]:::action E --> F["Supportive care:<br/>Correct electrolytes,<br/>Fluid resuscitation,<br/>Nutritional support"]:::action F --> G["Prevent relapse:<br/>Counseling, rehabilitation,<br/>Naltrexone/Acamprosate"]:::action ``` ### Benzodiazepine Dosing in DTs **Clinical Pearl:** Lorazepam dosing in severe withdrawal is **higher and more frequent** than in early withdrawal: - **Early withdrawal:** 1–2 mg IV q 5–10 min PRN - **DTs/severe withdrawal:** 2–4 mg IV q 5–10 min until patient is calm, then q 30 min–1 hr - **Goal:** Suppress tremor, reduce hallucinations, normalize vital signs - **Monitoring:** Continuous pulse oximetry, cardiac monitoring, frequent vital signs - **ICU level care** is mandatory because of seizure risk and respiratory depression from benzodiazepines ### Why This Is NOT Sepsis or Intracranial Injury **Sepsis differential:** While post-operative infection is possible, the **temporal relationship** (36 hours post-last drink, not post-operative day 2) and **hallucination pattern** (tactile, not delirium from infection) point to withdrawal. Blood cultures and antibiotics would be delayed and inappropriate without fever source. **Intracranial injury:** CT head is reasonable given trauma history, but the **classic DTs presentation** (autonomic + tactile hallucinations + confusion in known alcoholic) makes withdrawal diagnosis far more likely. CT should not delay benzodiazepine administration. ### Thiamine and Electrolyte Correction **High-Yield:** Always give **thiamine 100 mg IV before or with dextrose** to prevent Wernicke encephalopathy. Correct: - **Magnesium** (hypomagnesemia worsens withdrawal and seizure risk) - **Potassium** (hypokalemia increases arrhythmia risk in autonomic storm) - **Phosphate** (hypophosphatemia impairs ATP production) ### Prognosis and Follow-Up - **Mortality of untreated DTs:** 15–20% - **Mortality with treatment:** <5% - **Recovery:** Usually 3–7 days with supportive care - **Long-term:** Rehabilitation, psychosocial support, pharmacotherapy (naltrexone, acamprosate, disulfiram) for relapse prevention