Syed Aitizaz, Fawzy Hosam, Farag Atef, Nemlander Arto
Cardiac Services Department, North West Armed Forces Hospital, P.O. Box 100, Tabuk, Saudi Arabia.
Heart Lung Circ. 2004 Jun;13(2):168-72. doi: 10.1016/j.hlc.2004.03.015.
Cardiopulmonary bypass has been implicated as a cause of acute lung injury in cardiac surgical patients. This could be avoided with off-pump coronary artery bypass surgery. Aim. To ascertain the possible benefit of OPCAB surgery on pulmonary gas exchange.
We randomized 75 consecutive patients (mean age 57 years) into two groups: Group 1 off-pump coronary artery bypass surgery (OPCAB), n=37, Group 2 conventional coronary artery bypass grafting (con CABG), n=38. Alveolar-arterial oxygen difference (A-aO(2) difference) was calculated pre-operatively, then 2 and 4h post-operatively. PaO(2)/FiO(2) ratio and respiratory index (RI) were calculated 2 and 4h post-operatively.
Alveolar-arterial O(2) gradient sharply increased in the immediate post-operative period, from 27mmHg pre-operatively, to 227mmHg 2h post-operatively, then declined to 152mmHg 4h post-operatively. PaO(2)/FiO(2) ratio and RI also showed severe worsening 2h post-operatively, with marked improvement at 4h. The pattern of physiological deterioration of gas exchange was similar in both the groups.
In terms of pulmonary gas exchange, similar degree of deterioration is noticed in CABG patients with or without cardiopulmonary bypass. OPCAB seems to provide no physiological benefit of gas exchange at the alveolar capillary membrane when compared to conventional CABG.
体外循环被认为是心脏手术患者急性肺损伤的一个原因。非体外循环冠状动脉搭桥手术可以避免这种情况。目的：确定非体外循环冠状动脉搭桥手术（OPCAB）对肺气体交换可能带来的益处。
我们将75例连续患者（平均年龄57岁）随机分为两组：第1组为非体外循环冠状动脉搭桥手术（OPCAB）组，n = 37；第2组为传统冠状动脉搭桥术（con CABG）组，n = 38。术前、术后2小时和4小时计算肺泡 - 动脉血氧分压差（A - aO₂差值）。术后2小时和4小时计算PaO₂/FiO₂比值和呼吸指数（RI）。
术后即刻肺泡 - 动脉血氧梯度急剧增加，从术前的27mmHg升至术后2小时的227mmHg，然后在术后4小时降至152mmHg。PaO₂/FiO₂比值和RI在术后2小时也显示出严重恶化，在4小时时有明显改善。两组气体交换生理恶化的模式相似。
在肺气体交换方面，接受或未接受体外循环的冠状动脉搭桥术患者出现的恶化程度相似。与传统冠状动脉搭桥术相比，非体外循环冠状动脉搭桥术似乎在肺泡毛细血管膜气体交换方面未提供生理益处。
