[Hypoxemia during cesarean section due to massive pleural effusion in a patient with preeclampsia]

We report hypoxemia during cesarean section in a 33-year-old woman with preeclampsia. She developed generalized body weight increase, severe proteinuria and decrease of platelets at week 33 of gestation. Cesarean section was scheduled under general anesthesia. The patient did not complain of dyspnea preoperatively. After induction of general anesthesia, arterial oxygen saturation decreased from 99 to 88%. Massive left pleural effusion was detected and chest drainage was performed, and oxygenation was improved. Accumulation of pleural effusion tends to be over-looked because many parturients with pleural effusion do not complain of dyspnea. Physicians should pay attention to pleural effusion in parturients, especially those with risk factors such as preeclampsia, generalized body weight increase and administration of beta stimulant.