A 52-year-old male with COPD (FEV1 45% predicted) undergoes elective laparoscopic cholecystectomy under general anesthesia. Induction is achieved with propofol 1.5 mg/kg and succinylcholine 1.5 mg/kg. Five minutes into the procedure, the surgeon notes persistent abdominal distension and poor visualization. The anesthesiologist observes peak airway pressures rising from 18 cm H₂O to 32 cm H₂O over 10 minutes, with SpO₂ dropping to 88% and ETCO₂ rising to 58 mmHg. Breath sounds are equal bilaterally. Which of the following is the most likely complication and the most appropriate immediate management?

Explanation

## Clinical Analysis The constellation of findings—**rising airway pressures, hypoxemia, hypercarbia, poor surgical visualization, and abdominal distension during laparoscopic surgery**—is pathognomonic for **tension pneumoperitoneum**. ### Why Tension Pneumoperitoneum? **Mechanism:** - Excessive CO₂ insufflation or inadequate venting during laparoscopy creates a closed-space pressure that compresses the diaphragm and lungs. - Intra-abdominal pressure >12 mmHg impairs ventilation and venous return. - The patient's pre-existing COPD makes him more susceptible to ventilatory compromise. **Clinical Triad:** 1. **Mechanical**: Rising peak pressures (18→32 cm H₂O), poor surgical field 2. **Respiratory**: Hypoxemia (SpO₂ 88%), hypercarbia (ETCO₂ 58 mmHg) 3. **Physical exam**: Abdominal distension, but **equal bilateral breath sounds** (rules out pneumothorax) ### Immediate Management **First-line intervention:** Needle or trocar decompression of the peritoneal cavity. - Reduces intra-abdominal pressure immediately. - Restores ventilatory mechanics and oxygenation. - Allows surgeon to identify the cause (kinked insufflation tubing, malfunctioning CO₂ regulator, or excessive flow rate). **Supportive measures:** - Increase minute ventilation; consider pressure-controlled ventilation. - Ensure adequate oxygenation (FiO₂ 100% if needed). - Monitor hemodynamics (CO₂ insufflation and raised IAP impair venous return). ## Key Point: **Tension pneumoperitoneum is a surgical emergency during laparoscopy.** Equal breath sounds and the absence of acute hyperthermia exclude pneumothorax and malignant hyperthermia. The timing (early in procedure) and the surgeon's observation of poor visualization are critical clues.