两种通气模式对行腹腔镜直肠癌根治术老年患者肺保护作用的比较

Effects of two different mechanical ventilation modes on lung protection in elderly rectal cancer patients undergoing laparoscopic radical surgery

目的比较容量控制通气(VCV)与压力控制容量保证通气(PCV-VG)两种机械通气模式对行腹腔镜直肠癌根治术的老年患者围术期肺保护作用的效果。方法将60～80岁行择期腹腔镜直肠癌根治术的老年患者随机分为VCV组(59例)和PCV-VG组(58例)。于机械通气后10 min(T_0)和建立气腹后30 min(T_1)、60min(T_2)、90min(T_3)4个时间点记录两组患者的潮气量(V_t)、气道峰压(p_(peak))、气道平台压(p_(plat))、动态肺顺应性(C_(dyn))和呼气末二氧化碳分压(p_(et)CO_2)等呼吸力学参数;同时采集动脉血行血气分析,记录动脉血氧分压(paO2)和动脉血二氧化碳分压(paCO2)。各组患者于术后第7天行胸部CT检查,以观察术后肺部并发症的发生情况。结果两组T_1、T_2、T_3时间点的V_t、p_(peak)、p_(plat)、p_(et)CO_2和paCO2均显著高于同组T_0时间点(P值均<0.05)。PCV-VG组T_1至T_3时间点的p_(peak)和p_(plat)均显著低于VCV组同时间点(P值均<0.05),C_(dyn)均显著高于VCV组同时间点(P值均<0.05)。术后第7天,PCV-VG组肺不张和胸腔积液的发生率均显著低于VCV组(P值均<0.05),两组肺部感染发生率的差异无统计学意义(P>0.05)。结论对于行腹腔镜直肠癌根治术的老年患者,PCV-VG模式可在保证氧合与肺交换的前提下,降低气道压力,改善肺顺应性,并降低术后肺部相关并发症发生率,具有较好的肺保护作用。

Objective To compare the effect of volume-controlled ventilation （VOV） with pressure- controlled volume-guaranteed mechanical ventilation （PCV-VG） on perioperative lung protection in elderly patients undergoing laparoscopic radical resection of rectal carcinoma. Methods Elderly patients （aged 60- 80 years） scheduled for elective laparoscopic radical surgery for rectal cancer were randomly divided into VCV group （n = 59） and PCV-VG group （n = 58） in this prospective, randomized and single-blinded study. Hemodynamic and respiratory parameters were measured 10 min after mechanical ventilation （To）, 30 min （T1）, 60 rain （T2） and 90 min （T3） after pneumoperitoneum establishment. The parameters included tidal volume （V1）, peak inspiratory pressure （ Ppeak ）, plateau inspiratory pressure （ Pplat ）, dynamic lung compliance （Cdyn）, and end-tidal carbon dioxide partial pressure （Pet CO2 ）. At the same time points, radial artery blood was collected for blood gas analysis. Chest CT scanning was performed in each patient on day 7 after surgery to assess postoperative pulmonary complications （PPCs）. Results Compared with those at To, Vt, Ppeak, Pplat, Pet 002 and arterial partial pressure of carbon dioxide （paCO2） were significantly increased at T1, T2 and T3 in both groups （all P〈 0.05）. Compared with those in VGV group, Ppeak and Pptat were significantly increased at T1, T2 and T3 （all P〈 0.05）, whereas Cdyn was significantly increased in PCV-VG group （all P〈0.05）. The incidences of atelectasis and pleural effusion in PCV-VG group were significantly lower than those in VCV group on day 7 after surgery （both P〈0.05）. However, no significant difference was found in the incidence of pulmonary infection between the two groups （P〉0.05）. Conclusion PCV-VG can reduce inspiratory pressure and improve lung compliance with well oxygenation and pulmonary gas exchange. Moreover, PCV-VG mode can decrease the incidence of pulmonary atelectasis and pleural effusion. PCV-VG has better perioperative lung protection effects than VCV in elderly rectal cancer patients undergoing laparoscopic radical surgery.