Wooden Chest Syndrome is a side effect associated with fentanyl and relates to which phenomenon?

• A. Respiratory muscle rigidity (Wooden Chest Syndrome)
• B. Nasal congestion
• C. Hyperactivity
• D. Increased appetite

Answer: (A)

Fentanyl can cause a sudden increase in skeletal muscle tone, especially in the chest wall and respiratory muscles, a phenomenon known as Wooden Chest Syndrome. This central-motor effect results from potent mu-opioid receptor activation and rapid IV administration, leading to marked chest wall stiffness that hinders chest expansion and ventilation. It can occur even if the patient’s breathing rate seems preserved, and it may mimic airway obstruction or bronchospasm, making it a distinct and dangerous complication of high-dose or rapid fentanyl use. Treating it involves stopping or slowing fentanyl, reversing its effects with naloxone, and, if necessary, providing neuromuscular blockade and assisted ventilation to secure the airway. The other choices don’t fit because nasal congestion, hyperactivity, or increased appetite are not caused by this central chest-wall rigidity phenomenon.