Which side effect is seen with fentanyl?

Fentanyl induced chest wall rigidity is an uncommon complication, especially during sedation for routine bronchoscopy . It was first described by Hamilton and Cullen in 1953 . It primarily results in chest wall and abdominal wall rigidity, also known as the 'wooden chest syndrome . The reduced chest wall compliance makes rescue assisted ventilation difficult . This may also be contributed by vocal cords or jaw closure resulting in upper airway obstruction