A 48-year-old man with a 3-day history of acute pancreatitis presents to the emergency department with severe epigastric pain, vomiting, and hemodynamic instability (BP 92/58 mmHg, HR 118 bpm). He requires emergency intubation for airway protection and mechanical ventilation. His last oral intake was 4 hours ago. The anesthesiologist plans rapid sequence induction with propofol and succinylcholine. Which of the following modifications to standard RSI is MOST appropriate for this hemodynamically unstable patient?

Explanation

## RSI Modifications in Hemodynamic Instability ### Clinical Context: Septic Shock from Pancreatitis This 48-year-old man presents with: - Severe hypotension (92/58 mmHg) and tachycardia (118 bpm) - Signs of distributive shock (acute pancreatitis with SIRS) - High aspiration risk (recent oral intake, acute illness) - Requires emergency intubation **Key Point:** Propofol is a potent vasodilator and myocardial depressant; standard induction doses (2 mg/kg) can cause catastrophic hypotension in shock states. Dose reduction and alternative agents are mandatory. ### Recommended Approach for Hemodynamically Unstable Patients | Parameter | Standard RSI | Unstable Patient RSI | | --- | --- | --- | | **Propofol dose** | 2 mg/kg IV | 0.5–1 mg/kg IV (or omit) | | **Alternative agents** | — | Etomidate 0.2–0.3 mg/kg or Ketamine 1–1.5 mg/kg | | **IV access** | One large-bore IV | Two large-bore IVs + central line if available | | **Vasopressor prep** | Optional | Mandatory — draw up noradrenaline/dopamine before induction | | **Fluid bolus** | Not routine | 250–500 mL crystalloid if time permits | | **Monitoring** | Standard | Invasive BP monitoring if available; continuous ECG | **High-Yield:** Etomidate is often preferred in shock because it maintains hemodynamic stability better than propofol, though it causes adrenal suppression with single doses. Ketamine is also excellent — it maintains airway reflexes and has sympathomimetic effects. ### Step-by-Step Modification Protocol 1. **Pre-induction preparation:** - Establish two large-bore IVs - Draw up vasopressors (noradrenaline 4–8 mcg/min or dopamine 5–10 mcg/kg/min) - Prepare fluid for bolus if time permits - Position for rapid IV access augmentation 2. **Induction agent selection:** - Propofol: Reduce to 0.5–1 mg/kg (or avoid entirely) - Preferred: Etomidate 0.2–0.3 mg/kg or Ketamine 1–1.5 mg/kg 3. **Neuromuscular blockade:** - Succinylcholine 1–1.5 mg/kg is acceptable (hyperkalemia risk is secondary to hemodynamic stability) - Rocuronium 1.2 mg/kg is alternative if succinylcholine contraindicated 4. **Post-induction:** - Initiate vasopressor infusion immediately - Avoid high-pressure ventilation; use lower tidal volumes (6–8 mL/kg IBW) to prevent barotrauma **Clinical Pearl:** In profound shock, consider **awake fiberoptic intubation** if time permits and airway anatomy is favorable — this preserves spontaneous ventilation and sympathetic tone. However, in this acute pancreatitis case with aspiration risk, RSI with modifications is appropriate. **Mnemonic: SHOCK-RSI** — **S**uccinylcholine acceptable, **H**alf-dose propofol or alternative, **O**xygen pre-oxygenation (still do it!), **C**entral line if available, **K**etamine or etomidate preferred [cite:Miller's Anesthesia 8e Ch 28; Barash Clinical Anesthesia 8e Ch 20]