Venous emboli occurring caesarean section: the effect of patient position.

The effect of position, horizontal versus 5 degrees reverse Trendelenburg's, on the incidence of venous emboli during Caesarean section was evaluated in 207 patients. Venous emboli were diagnosed using precordial ultrasonic Doppler monitoring. In the horizontal position, 44% (60 of 134) parturients had venous emboli compared with 1% (1 of 73) parturients in the 5 degrees reverse Trendelenburg's position (P less than 0.0001). Epidural anaesthesia was performed in 171 patients, and 36 patients had general anaesthesia. In the epidural group, pulse oximetric haemoglobin oxygen desaturation and complaints of chest pain and/or dyspnoea were associated with the venous emboli. Venous emboli, probably air, occur frequently during Caesarean section with the patient in the horizontal position. This occurrence was minimized by placing the patient in the 5 degrees reverse Trendelenburg's position.