Archive | 2021
Wooden Chest Syndrome: Fentanyl Induced Chest Wall Rigidity
Abstract
Fentanyl induced chest wall rigidity, otherwise known as Wooden Chest Syndrome, is a rare complication of fentanyl characterized by a patient s inability to properly ventilate. We present a patient with acute respiratory distress syndrome (ARDS) who developed this syndrome in a medical intensive care unit (ICU) setting. A 61- year-old female with a history of prior episodes of pancreatitis presented with a chief complaint of left-sided, sharp, abdominal pain associated with nausea. Physical exam demonstrated epigastric tenderness without rebound or guarding. Chest exam demonstrated strong inspiratory effort and was negative for rales, rhonchi, or accessory muscle use. Vital signs demonstrated no abnormalities and she had oxygen saturation levels greater than 92% on room air. Laboratory findings revealed an elevated lipase of 1086 u/L. A diagnosis of pancreatitis was made. The patient was given intravenous fluids and made NPO. The patient developed respiratory distress and chest x-ray findings revealed bilateral infiltrates consistent with ARDS, requiring endotracheal intubation. She was sedated with intravenous fentanyl and midazolam to a Richmond Agitation-Sedation Scale (RASS) goal of -4. The fentanyl infusion was incrementally increased and maximized to 300mcg/hr. Following maximizing the fentanyl infusion, the patient began experiencing periods of hypoxia. Physical exam at this time was significant for a tense abdomen, facial cyanosis, and episodes of what appeared to be breath holding spells. Ventilator readings revealed drastically elevated airway pressures. The patient required bag valve mask ventilation which was met by strong resistance. Passage of the suction catheter revealed no obstruction or mucus. An emergent bedside bronchoscopy confirmed these findings. A repeat chest X-ray revealed no pneumothorax. This presentation raised concern for Wooden Chest Syndrome. The fentanyl infusion was titrated down and she was transitioned to dexmedetomidine. The patient exhibited no further episodes was successfully extubated three days later. Chest wall skeletal muscle rigidity is a result of fentanyl bound mu opioid receptors on the central nervous system and activation of a dopaminergic pathway. The subsequent decreased chest wall compliance results in ineffective assisted and spontaneous ventilation, translating to elevated pressures within the ventilator circuit. Management of this syndrome is with the opioid receptor antagonist Naloxone, neuromuscular blocking agents such as rocuronium, or cessation of fentanyl infusion with supportive care. Given the COVID-19 pandemic and surge in ICU admissions, analgesic fentanyl use is rising. Therefore, an understanding of this rare complication is necessary.