低潮气量联合呼气末正压通气对慢性阻塞性肺疾病患者腹腔镜手术时肺功能的影响

Effects of mechanical ventilation with lower tidal volume and positive end-expiratory pressure on pulmonary function during laparoscopic surgery in patients with chronic obstructive pulmonary disease

目的 探讨低潮气量联合呼气末正压（PEEP）通气对慢性阻塞性肺疾病（COPD）患者腹腔镜手术时肺功能的影响.方法 择期拟行腹腔镜结肠癌、直肠癌或宫颈癌根治术的合并COPD患者40例,年龄60 ～ 82岁,体重指数16 ～ 29 kg/m2,采用随机数字表法,将其分为2组（n=20）：常规机械通气组（Ⅰ组）和低潮气量联合PEEP通气组（Ⅱ组）.Ⅰ组新鲜气体流量2L/min,VT10 mYkg,吸呼比为1∶2;Ⅱ组新鲜气体流量2 L/min,VT 6 ml/kg,吸呼比为1∶2,PEEP 6 cm H2O.调整通气频率,维持PET CO2 35 ～45 mm Hg.于气管插管后5min（T1）、气腹45 min（T2）和气腹结束后15 min（T3）时记录气道蜂压（Ppeak）、气道平台压（Pplat）、动态肺顺应性（Cdyn）和气道阻力（Raw）,并取桡动脉血样行血气分析,计算肺泡-动脉血氧分压差（A-aDO2）、氧合指数（PaO2/FiO2）、呼吸指数（RI）和死腔率（VD/VT）.记录拔管时间和术后48 h内相关并发症的发生情况.结果 与Ⅰ组比较,Ⅱ组T2时Ppeak和Ppplat、T1,2时Raw降低,T2时Cdyn升高,T1-3时PaO2/Fiq升高,RI、VD/VT和A-aDO2降低,术后48 h内低氧血症、肺不张和新出现肺部哕音发生率降低（P＜0.05）,拔管时间差异无统计学意义（P＞0.05）.结论 低潮气量（6 ml/kg）联合PEEP（6 cm H2O）通气可改善COPD患者腹腔镜手术期间的肺功能.

Objective To investigate the effects of mechanicl ventilation with lower tidal volume and positive end-expiratory pressure （PEEP） on pulmonary function during laparoscopic surgery in patients with chronic obstructive pulmonary disease （COPD）.Methods Forty patients with COPD,aged 60-82 yr,with body mass index of 16-29 kg/m2,undergoing elective laparoscopic surgery,were randomly divided into 2 groups （n =20 each） using a random number table：conventional ventilation group （group Ⅰ） and mechanical ventilation with lower tidal volume and PEEP group （group Ⅱ）.Anesthesia was induced with midazolam,sufentanil,cisatracurium and propofol and maintained with iv infusion of propofol,cisawacurium and remifentanil.The patients were endotracheally ventilated and mechanically ventilated.In group Ⅰ,fresh gas flow was set at 2 L/min,VT at 10 ml/kg,and I∶E at 1∶2 during ventilation.In group Ⅱ,fresh gas flow was set at 2 L/min,VT at 6 ml/kg,I∶E at 1∶2 and PEEP at 6 cm H2O during ventilation.PErCO2 was maintained at 35-45 mm Hg in both groups.Airway peak pressure （Pp~）,airway plateau pressure （Pplat）,airway resistance （Raw） and dynamic lung compliance （Cdyn） were measured at 5 min after intubation （T1）,45 min of pneumoperitoneum （T2）,and 15 min after the end of pneumoperitoneum （T3）.Arterial blood samples were obtained at T1,T2 and T3 for blood gas analysis.Alveolar-arterial oxygen gradiant （A-aDO2）,oxygenation index （PaO2/FiO2）,respiratory index （RI） and physiologic dead space fraction （VD/VT） were calculated.The extubation time and development of complications were recorded within 48 h after operation.Results Compared with group Ⅰ,Ppeak and Plat at T2 and Raw at T1,2 were significantly decreased,Cdyn at T2 and PaO2/FiO2 at T1-3 were significantly increased,RI,VD/VT and A-aDO2 were significantly decreased at T1-3,and the incidence of hyoxemia,atelectasis and rales was decreased within 48 h after operation in group Ⅱ （P ＜ 0.05）.There was no significant difference in the extubation time between the two groups （P ＞ 0.05）.Conclusion Mechanical ventilation with lower tidal volume （6 nl/kg） and PEEP （6 cm H2O） can improve the pulmonary function during laparoscopic surgery in patients with COPD.