无创正压通气对心外科术后呼吸困难患者的应用研究

Efficacy and safety of non -invasive positive pressure ventilation in the care of dyspnea after cardiac surgery

目的研究无创正压通气（NPPV）用于心外科体外循环术后呼吸困难的价值。方法对2004年12月-2006年12月本院心外科体外循环术后部分患者在拔管后发生呼吸困难（呼吸频率〉25次/min及三凹征）或急性呼吸衰竭时,随机用NPPV或面罩吸氧两种方法对患者进行呼吸支持,NPPV组30例,面罩吸氧组28例。两组患者在治疗效果差、仍缺氧〔动脉血氧分压（PaO2）〈60mmHg（1mmHg=0.133kPa）〕,或出现严重室性心律失常及其他气管插管指征时,则予以再次气管插管行有创机械通气。结果两组年龄、急性生理学与慢性健康状况评分系统（APACHE）评分、体外循环时间、主动脉阻断时间、术前纽约心功能分级等一般情况比较差异均无显著性（P均〉0.05）。与面罩吸氧组比较,NPPV组治疗120min后心律失常发生率、需气管插管率、住重症加强治疗病房（ICU）天数、ICU病死率均显著下降（P〈0.05或P〈0.01）。与0min时比较,两组pH于480min时明显上升（P均〈0.05）;PaCO2于120min起开始上升（P均〈0.05）,480min时明显上升（P均〈0.01）。与0min时比较,NPPV组于30min起PaO2、HCO3-显著升高,呼吸频率、心率、动脉收缩压显著下降,差异均有显著性（P〈0.05或P〈0.01）;而面罩吸氧组PaO2、HCO-3、呼吸频率、心率、动脉收缩压分别于120、60、120、480和480min开始出现显著性差异（P〈0.05或P〈0.01）。与0min时比较,NPPV组乳酸于60min起开始出现下降,差异有显著性（P〈0.05）;而面罩吸氧组则于480min时才开始出现下降,差异有显著性（P〈0.05）。结论NPPV是解决心外科术后呼吸困难、急性呼吸衰竭的一种安全、有效方法,在选择性心外科手术后患者中积极使用NPPV可明显缓解呼吸困难,改善组织灌注,减少术后心律失常的发生,降低术后再插管的需要,缩短住ICU时间,降低病死率。

Objective To study the efficacy and safety of non - invasive positive pressure ventilation （NPPV） in the care of dyspnea after cardiac surgery. Methods Among patients who underwent cardiac surgery with cardiopulmonary bypass from December 2004 to December 2006,58 patients developed dyspnea （respiratory rate〉 25 breaths per minute with ＂three depressions＂ sign） and acute respiratory failure after extubation. Among them 30 patients underwent NPPV and 28 patients were treated with face mask oxygen therapy. Bation and invasive mechanical ventilation were begun when the treatment failed or still hypoxemic [partial pressure of oxygen in artery （PaO2）〈60 mm Hg （1 mm Hg= 0. 133 kPa）], ventricle arrhythmia, or other indications for endotracheal intubation. Results No significant differences were found between two groups in age, acute physiology and chronic health evaluation Ⅱ （APACHE Ⅱ ） score, duration of cardiopulmonary bypass and aortic cross - clamp, and New York Heart Association class （all P〉 0.05）. Compared with face mask oxygen therapy group, NPPV was associated with a lower incidence of arrhythmia （P〈0.05） at 120 minutes after treatment, a lesser necessity for reintubation （P〈0.01）, a shorter length of stay in intensive care unit （ICU） （P〈0.01）, a lower mortality （P〈0.05）. Arterial pH and arterial CO2 partial pressure （PaCO2） of two groups began to rise significant at 480 minutes （P〈0.05 or P〈0.01）, PaCO2 began to rise at 120 minutes （P〈0.05）. At 30 minutes, significant differences in PaO2, HCO3^-, respiratory rate, heart rate and arterial systolic blood pressure in NPPV group began to appear （P〈0.05 or P〈0.01）. The time of significant differences in PaO2, HCO3^-, respiratory rate, heart rate and arterial systolic blood pressure in face mask oxygen therapy group were respectively 120, 60, 120, 480 and 480 minutes （P〈0.05 or P〈0.01）. Lactate concentration showed a significant drop at 60 minutes in NPPV （P〈0.05）, but at 480 minutes in face mask oxygen therapy group （P〈0.05）. Conclusion These results suggest that NPPV is an effective and safe means for improving dyspnea and tissue perfusion, decreasing arrhythmia and necessity for reintubation, shortening the length of stay in ICU and decreasing mortality in dyspneic patients after cardiac surgery.