Concomitant cardiac and pulmonary operation - Pulmonary mechanics and outcome of phrenic nerve injury

Objective. We describe the postoperative respiratory failure due to the phrenic nerve injury in the setting of concomitant cardiac and pulmonary operation. Experimental study. Prospective study. Setting. Department of Cardiac and Thoracic Surgery Osaka University Medical School. Patients and interventions. From January 1984 to December 1993, 5 patients (1.4 %) underwent the concomitant cardiac and pulmonary operation out of 359 patients who received surgical treatment for lung cancer at our institution. Measures and results. Three (60%) out of 5 patients required prolonged mechanical ventilation despite the absence of cardiac complication, lung edema or pneumonia. Diaphragm function and work of breathing were measured in two patients before and after weaning from mechanical ventilation. Phrenic nerve dysfunction was consistent with the result that transdiaphragmatic pressure (Delta Pdi) was low, a ratio of gastric to esophageal pressure swing (Delta Pga/Delta Pes) was abnormally negative, and work of breathing (WOB) was high. Phrenic nerve function restored associated with clinical improvement. Conclusions. Diaphragm dysfunction and an increase in work of breathing may be potential causes of respiratory failure in patients after concomitant cardiac and pulmonary operation. This compromise in respiratory mechanics should not be overlooked in the postoperative care, which may lead to the best management in postoperative respiratory care.