The Silent Threat of Wooden Chest Syndrome: Prompt Management of Fentanyl-Induced Muscle Rigidity in the Intensive Care Unit.

Introduction: Wooden chest syndrome (WCS) is a rare, potentially fatal complication of high-dose fentanyl therapy, characterized by generalized muscle rigidity, reduced chest wall compliance, and acute respiratory distress. Frequently underdiagnosed in the intensive care unit (ICU), WCS poses a significant challenge due to its rapid onset and potential to cause ventilatory failure if not addressed promptly. This case report examines WCS in a postoperative setting, emphasizing its recognition and management to improve patient outcomes.

Case presentation: A 49-year-old female with a history of cervical cancer, hypertension, and recent sigmoidectomy developed WCS 8 hours after starting a fentanyl infusion (50 μg/h, total ~400 μg) following an emergent incision and drainage for a 4 × 3 cm neck abscess. Initially stable on pressure-regulated volume control ventilation (peak airway pressure, Ppeak 20 cmH₂O, tidal volume 450 ml), she presented with sudden chest wall rigidity, respiratory rate of 28 breaths/min, and Ppeak rising to 35 cmH₂O, alongside respiratory acidosis (pH 7.28, PaCO₂ 58 mmHg). Fentanyl was stopped, naloxone (2 mg IV) administered, and ventilation shifted to pressure control mode of 25 cmH₂O above positive end-expiratory pressure. Dexmedetomidine (0.5 μg/kg/h) replaced opioids for sedation. Symptoms resolved within 4 hours, enabling a transition to pressure support mode and extubation on postoperative day 2, with discharge to the floor by day 5.

Conclusion: This case highlights WCS as a critical, reversible opioid-related complication in the ICU, necessitating vigilance during prolonged fentanyl use (>8 hours). Early detection via ventilator changes (e.g., Ppeak elevation) and swift intervention with naloxone and non-opioid sedation can prevent adverse outcomes. Increased awareness, staff training, and further research are vital to enhance ICU safety.

Learning points: Early detection is crucial: wooden chest syndrome can manifest as sudden muscle rigidity and rising peak airway pressures within 8 hours of fentanyl infusion, requiring prompt recognition to prevent ventilatory failure.Ventilator changes guide diagnosis: elevated peak pressures with stable plateau pressures signal wooden chest syndrome, distinguishing it from lung pathology, and warrant immediate investigation.Swift management improves outcomes: stopping fentanyl, administering naloxone, and using dexmedetomidine can reverse wooden chest syndrome rapidly, enabling extubation within 48 hours.