Lange Anesthesiology > Section III. Regional Anesthesia & Pain Management > Chapter 18. Pain Management

Case Discussion: Analgesia Following Thoracoabdominal Surgery

"An obese 21-year-old male is admitted to the recovery room following a right thoracoabdominal lymph node dissection for a testicular malignant growth. The incision extends from the eighth rib to the pubis and a right thoracostomy (chest tube) is present. He had consented to an epidural catheter for managing his pain postoperatively. Unfortunately, placement of the catheter prior to surgery proved to be very difficult because of his obesity, and could not be accomplished. He is extubated and awakens from anesthesia in severe pain and is noted to have shallow breathing at a rate of 35/min ("splinting"). A total of 10 mg of morphine sulfate is given intravenously before he stops complaining of pain and becomes very drowsy again.The patient is at high risk for pulmonary complications because of his obesity and the extensive thoracoabdominal incision. He is unable to take deep breaths or cough effectively, and already has hypoxemia and respiratory acidosis. In fact, if his respiratory status cannot be improved promptly, endotracheal intubation and controlled mechanical ventilation should be considered. The chest film is very helpful in excluding residual right pneumothorax, significant hemothorax, or lobar atelectasis that could explain his marginal respiratory status. The most likely explanation of these findings is inadequate pain relief combined with opioid-induced respiratory depression. The hypoxemia is most likely due to microatelectasis and a low functional residual capacity (see Chapter 22), whereas the hypoventilation is due..."