Haemodynamic changes during thoracoscopic surgery -: The effects of one-lung ventilation compared with carbon dioxide insufflation

We investigated the haemodynamic and respiratory effects of one-lung ventilation and carton dioxide insufflation in 13 adult patients undergoing video-assisted thoracoscopy. Cardiorespiratory variables were determined during carbon dioxide insufflation at intrahemithoracic pressures of 5, 10 and 15 mmHg, and after 5 and 15 min of one-lang ventilation. Carbon dioxide insufflation was associated with a clear deterioration in circulatory function. The cardiac index decreased subsequent to increasing intrathoracic pressures. The mean cardiac index (SD) at pressures of 10 and 15 mmHg was 1.86 (0.39) and 1.52 (0.46), respectively, and may be compared with the reduced venous return consistent with tension pneumothorax. One-lung ventilation did not affect haemodynamic variables but reduced arterial oxygenation indices (P(a)o(2)/F(I)o(2)) from 424.29 (160.79) after induction of anaesthesia, to 207.72 (125.50) after 5 min and 172.04 (72.03) after 15 min of one-lung ventilation, respectively. The oxygenation index was not influenced by intrahemithoracic carbon dioxide insufflation. One-lung ventilation via a double-lumen endobronchial tube is safe and convenient for video-assisted thoracoscopic surgery. It has no further consequences on haemodynamic variables, whereas the compression of the lung by carbon dioxide insufflation may cause circulatory dysfunction.