定压和定容两种通气模式对儿童肺叶切除术中呼吸生理的影响

目的 观察定压和定容通气模式对儿童气管插管麻醉下行肺叶切除术中呼吸力学及动脉血气的影响.方法 选择40例ASAⅠ～Ⅱ级行择期肺叶切除术患儿,在知情同意下随机分为VCV组和PCV组各20例,麻醉诱导后行气管插管,VCV组先采用定容模式通气,潮气量为8～10 ml/kg,30 min后改为定压通气,压力设定根据定容通气时的气道平台压而定.PCV组先采用定压模式通气,压力设定以通气量达到满意为准,30 min后改为定容模式通气,潮气量根据定压时的潮气量而定.观察比较两组气道峰压、气道平台压、气道阻力、分钟通气量、呼气分钟通气量、呼吸末二氧化碳分压等及麻醉前、通气后30 min和60 min动脉血气变化情况.结果 两组气道峰压、气道平台压、气道阻力差异均无统计学意义（均P＞0.05）,与VCV组相比较,PCV组吸气分钟通气量、呼气分钟通气量均增加,且差异均有统计学意义（t=4.135、3.988,均P＜0.05）;血气分析显示,PCV组Pa02（176.1±56.9）mm Hg明显高于VCV组的（126.3±46.8）mm Hg（t=3.183,P＜0.05）,两组PaC02分别为（35.8±6.7）mm Hg、（36.5±6.9）mm Hg,差异无统计学意义（P＞0.05）.结论 儿童肺叶切除术中采用定压通气较定容通气模式更有利于防止通气造成的动脉血氧分压下降.

Effects of two modes of ventilation on pediatric patients undergoing lung lobectomy

Objective To investigate the effect of two modes of ventilation on pediatric patients undergoing lung lobectomy.Methods Forty ASA Ⅰ～Ⅲ patients aged 2～10 years,undergoing lung lobectomy were randomly divided into VCV and PCV group(n=20).After general anesthesia,patients in VCV group were ventilated on volume-control mode maintaining 30min and then changed into pressure-control mode;patients in PCV group were ventilated on pressure-control mode maintaining 30min and then changed into volume-control mode.Ppeak,Pplat,Raw,MVI,MVE and EtCO2 were measured according to SSS monitor system.All the patients were treated with traumatic blood pressure measurement,and all the patients were analyzed during the period of pre-operation,30min and 60min after ventilation.Results Compared with VCV group,breathing mechanics MVI and MVE in the PCV group were increased(t=4.135,3.988,P＜0.05)and PaO2 in the PCV group was significantly increased(t=3.183,P＜0.05),as compared with those on volume-control mode.Conclusion PCV mode was benefit for preventing low oxygen in lung lobectomy surgery.