Laryngospasm-Induced Negative-Pressure Pulmonary Edema After Laparoscopic Appendectomy in a Young Adult: A Case Report

Negative-pressure pulmonary edema (NPPE) is an uncommon postoperative form of noncardiogenic pulmonary edema resulting from forceful inspiratory efforts against an obstructed upper airway. A 20-year-old man (62 kg, 172 cm; body mass index, 21.0 kg/m²) underwent laparoscopic appendectomy under general anesthesia. Preoperative oxygen saturation was 98% on room air. Immediately after extubation, laryngospasm occurred, followed by acute respiratory distress, oxygen desaturation to 74%, tachypnea at 35 breaths/min, and tachycardia at 125 beats/min. Arterial blood gas analysis showed pH 7.33, PaCO₂ 32 mmHg, and PaO₂ 53 mmHg. Chest radiography demonstrated bilateral patchy central air-space opacities, more pronounced in the right lung, without apparent cardiomegaly. High-sensitivity troponin T was within the reference range. NPPE secondary to post-extubation laryngospasm was diagnosed. Continuous positive airway pressure (CPAP) at 5 cmH₂O with supplemental oxygen was initiated, and a single 20-mg intravenous dose of furosemide was administered. Respiratory status progressively improved, and the patient was discharged in good condition on postoperative day 3. This case emphasizes rapid recognition of the laryngospasm-hypoxemia-pulmonary edema sequence and careful assessment of competing postoperative diagnoses.