[Right phrenic nerve palsy in a patient with ventricular septal perforation after acute myocardial infarction]

A 77-year-old female had acute myocardial infarction and ventricular septal perforation (VSP). An operation was performed 14 days after VSP. During cardiopulmonary bypass, a patch was sutured in place on the left side of the defect under a mild hypothermia with topical cardiac cooling procedure. In the postoperative period, mechanical ventilation was continued with use of pulmonary monitor (CP-100, BICORE). When the patient was weaned of mechanical ventilation, work of breathing increased (WOBp: 1.67 J.l-1) without the change of SaO2, PaO2, PaCO2 and the respiratory state. After extubation, the chest X-ray showed elevated right diaphragmatic level and a diagnosis of unilateral diaphragmatic paralysis was made. Oral intake was started two days after extubation. SpO2 decreased after oral intake, and it was significantly improved by taking a left lateral position. The symptoms disappeared 47 days after the operation. It should be noticed that the rise of endoceliac pressure in the patient who had a unilateral phrenic nerve palsy, affected the SpO2.