心内直视手术后长时间呼吸机支持的危险因素分析

目的　分析心内直视手术后影响患者呼吸机辅助时间的危险因素 ,提高心内直视手术后呼吸并发症的诊治水平。方法　回顾性分析我院在 1995年 1月— 2 0 0 3年 8月期间长时间呼吸机辅助呼吸的 5 0例成人患者的临床资料 ,并用多因素线性回归分析模型评价各影响因素的作用大小。结果　本组患者年龄 14～6 5岁 ;体质量 2 8～ 80 kg;男性 2 8例 ,女性 2 2例 ;平均转流时间 (15 6 .38± 5 2 .0 2 ) m in;术后呼吸机辅助时间为 (6 2 .86± 2 2 .5 5 ) h;病死率为 18.0 %。与对照组相比 ,长时间呼吸机辅助呼吸组患者术前心功能差(P<0 .0 0 1) ,体外循环时间与阻断时间长 (P<0 .0 0 1) ,术后动脉血氧分压 (Pa O2 )及氧合指数 (Pa O2 /Fi O2 )低(P<0 .0 0 1) ,而术后肺泡动脉血氧分压差 (A a DO2 )高 (P<0 .0 0 1) ,肺内分流 (Qs/Qt)增大 (P<0 .0 0 1) ,术后肺动态顺应性 (PCD)无明显区别 ,术后引流量较多 (P<0 .0 0 1) ,术后心肌酶谱水平高 (P<0 .0 0 1) ,术后并发症的发生率也较高 (P<0 .0 0 1)。经多因素线性回归分析结果显示 ,术后呼吸机辅助呼吸时间与患者术前心功能、术中转流时间、术后 Pa O2 /Fi O2 、术后心肌酶谱水平及术后引流量明显相关。结论　心内直视手术患者术前心功能差、术中转流时间长、术中心肌

Investigation on risk factors of prolonged mechanical ventilation after cardiopulmonary bypass

OBJECTIVE: To analyze the risk factors of prolonged mechanical ventilation (PMV) after cardiopulmonary, and to improve the management for the patients underwent respiratory complications. METHODS: From January 1995 to August 2003, there occurred 50 cases of patients in our ICU. The clinical data of 50 cases of patients in our ICU who undergoing open heart surgery was reviewed retrospectively, and the multivariate liner regress analysis model was used to evaluate the influence of the variables. RESULTS: The age of the patients underwent PMV ranged from 14 to 65 years old, body weight 28 to 80 kg, 28 cases of the patients were male, and 22 female. Mean cardiopulmonary bypass (CPB) time was (156.38+/-52.02) minutes. Mean mechanical ventilation time was (62.86+/-22.55) hours. The mortality was 18.0 percent. Compared to the contrast, the patients in prolonged ventilation groups were in higher NYHA class, underwent longer period of CPB time and cross-clamping time (P<0.001). The postoperative arterial partial pressure of oxygen (PaO(2)) and PaO(2)/FiO(2) were much lower, the alveolar-arterial oxygen pressure gradient and the intrapulmonary shunt (Qs/Qt) were higher (all P<0.001). There was no significant difference in pulmonary dynamic compliance between the two groups. The postoperative drainage was much more, and the myocardial enzymes were in higher level in prolonged ventilation groups (both P<0.001). The incidence of postoperative complications was higher (P<0.001). Multivariate liner regress analysis showed that the duration of mechanical ventilation was related with the preoperative cardiac function, CPB time, PaO(2)/FiO(2), the level of postoperative myocardial enzyme, and the quantity of postoperative drainage. CONCLUSION: This study shows preoperative cardiac function, CPB time, PaO(2)/FiO(2), the level of postoperative myocardial enzyme and the quantity of postoperative drainage are risk factors of PMV.