Chaney M A, Nikolov M P, Blakeman B P, Bakhos M
Department of Anesthesia and Critical Care, University of Chicago, IL 60637, USA.
J Cardiothorac Vasc Anesth. 2000 Oct;14(5):514-8. doi: 10.1053/jcan.2000.9487.
To ascertain if protective ventilation can attenuate the damaging postoperative pulmonary effects of cardiopulmonary bypass (increases in airway pressure, decreases in lung compliance, and increases in shunt).
Prospective, randomized clinical trial.
Single university hospital.
Twenty-five patients undergoing elective coronary artery bypass graft procedure and early extubation.
Thirteen patients received conventional mechanical ventilation (CV; respiratory rate, 8 breaths/min; tidal volume, 12 mL/kg; fraction of inspired oxygen [FIO2], 1.0; positive end-expiratory pressure [PEEP], +5), and 12 patients received protective mechanical ventilation (PV; respiratory rate, 16 breaths/min; tidal volume, 6 mL/kg; FIO2, 1.0; PEEP, +5). Perioperative anesthetic and surgical management were standardized. Various pulmonary parameters were determined twice perioperatively: 10 minutes after intubation and 60 minutes after arrival in the intensive care unit.
The mean postoperative increase in peak airway pressure in group CV was significantly larger than the mean postoperative increase in peak airway pressure in group PV (7.1 v 2.4 cm H2O; p < 0.001). Group CV experienced significant postoperative increases in plateau airway pressure (p = 0.007), but group PV did not (p = 0.644). The mean postoperative decrease in dynamic lung compliance in group CV was significantly larger than the mean postoperative decrease in dynamic lung compliance in group PV (14.9 v 5.5 mL/cm H2O; p = 0.002). Group CV experienced significant postoperative decreases in static lung compliance (p = 0.014), but group PV did not (p = 0.645). Group CV experienced significant postoperative increases in shunt (15.5% to 21.4%; p = 0.021), but group PV did not (18.4% to 21.2%; p = 0.265).
Data indicate that protective ventilation decreases pulmonary damage caused by mechanical ventilation in normal and abnormal lungs. The results of this investigation indicate that protective ventilation may also help attenuate the postoperative pulmonary dysfunction (increases in airway pressure, decreases in lung compliance, and increases in shunt) commonly seen in patients after exposure to cardiopulmonary bypass.
确定保护性通气是否可减轻体外循环术后对肺的损害作用（气道压力升高、肺顺应性降低及分流增加）。
前瞻性随机临床试验。
单一大学医院。
25例行择期冠状动脉旁路移植术并早期拔管的患者。
13例患者接受传统机械通气（CV；呼吸频率8次/分钟；潮气量12毫升/千克；吸入氧分数[FIO2]1.0；呼气末正压[PEEP]+5），12例患者接受保护性机械通气（PV；呼吸频率16次/分钟；潮气量6毫升/千克；FIO2 1.0；PEEP +5）。围手术期麻醉和手术管理标准化。围手术期对多种肺参数进行两次测定：插管后10分钟及进入重症监护病房后60分钟。
CV组术后气道峰压平均升高幅度显著大于PV组术后气道峰压平均升高幅度（7.1对2.4厘米水柱；p<0.001）。CV组术后平台气道压显著升高（p = 0.007），而PV组未升高（p = 0.644）。CV组术后动态肺顺应性平均降低幅度显著大于PV组术后动态肺顺应性平均降低幅度（14.9对5.5毫升/厘米水柱；p = 0.002）。CV组术后静态肺顺应性显著降低（p = 0.014），而PV组未降低（p = 0.645）。CV组术后分流显著增加（15.5%至21.4%；p = 0.021），而PV组未增加（18.4%至21.2%；p = 0.265）。
数据表明，保护性通气可减轻正常及异常肺中机械通气所致的肺损伤。本研究结果表明，保护性通气可能也有助于减轻体外循环术后患者常见的术后肺功能障碍（气道压力升高、肺顺应性降低及分流增加）。
