A 58-year-old male with hypertension and type 2 diabetes mellitus is undergoing elective laparoscopic cholecystectomy under general anesthesia. After induction with propofol and intubation with succinylcholine, the patient's SpO₂ drops to 88% and systolic blood pressure falls to 78 mmHg. Auscultation reveals bilateral air entry. What is the most appropriate immediate next step?

Explanation

## Clinical Context The patient presents with simultaneous hypoxia (SpO₂ 88%) and hypotension (SBP 78 mmHg) immediately after induction and intubation. Bilateral air entry is present, ruling out unilateral obstruction or pneumothorax. ## Differential Diagnosis of Perioperative Hypotension + Hypoxia | Cause | Key Finding | Next Step | |-------|-------------|----------| | Inadequate ventilation / tube malposition | Unilateral breath sounds or no capnography | Reposition tube, verify with capnography | | Hypoxemia from low FiO₂ | SpO₂ <90% with adequate ventilation | Increase FiO₂ to 100% immediately | | Propofol-induced vasodilation | Bilateral air entry, normal ventilation | Fluid bolus, vasopressor if refractory | | Anaphylaxis | Rash, bronchospasm, angioedema | Epinephrine IM/IV | | Tension pneumothorax | Unilateral breath sounds, tracheal deviation | Emergency needle decompression | ## Rationale for Correct Answer **Key Point:** When hypoxia and hypotension occur immediately post-induction with bilateral air entry, the **first priority is to optimize oxygenation** before attributing hypotension to anesthetic drugs alone. 1. **Increase FiO₂ to 100%** — increases alveolar oxygen tension and rapidly improves SpO₂ in most cases of perioperative hypoxemia. 2. **Verify ETT position** — auscultation confirms bilateral air entry (already done), but capnography confirms adequate ventilation and rules out tube migration into right mainstem or esophagus. 3. **Hypotension is likely secondary** — propofol causes dose-dependent vasodilation and myocardial depression. Once oxygenation is secured, hypotension can be managed with fluid bolus, reduced propofol infusion, or vasopressors if needed. **Clinical Pearl:** The "ABCDE" rule in perioperative crisis: **Airway → Breathing → Circulation**. Securing oxygenation (Breathing) takes precedence over treating hypotension (Circulation) when both occur together, unless the patient is in cardiac arrest. **High-Yield:** Capnography is the gold standard for confirming endotracheal intubation and adequate ventilation. A normal waveform rules out esophageal intubation and severe hypoventilation. ## Why Hypotension Alone Is Not the Primary Problem Propofol-induced hypotension is **expected and managed expectantly** with fluids and reduced infusion rate — not with epinephrine as first-line. However, unexplained hypoxia in the presence of bilateral air entry suggests either inadequate ventilation parameters or low inspired oxygen concentration, both of which are correctable immediately.