Nava S, Ambrosino N, Clini E, Prato M, Orlando G, Vitacca M, Brigada P, Fracchia C, Rubini F
Centro Medico di Riabilitazione di Montescano, Italy.
Ann Intern Med. 1998 May 1;128(9):721-8. doi: 10.7326/0003-4819-128-9-199805010-00004.
In patients with acute exacerbations of chronic obstructive pulmonary disease, mechanical ventilation is often needed. The rate of weaning failure is high in these patients, and prolonged mechanical ventilation increases intubation-associated complications.
To determine whether noninvasive ventilation improves the outcome of weaning from invasive mechanical ventilation.
Multicenter, randomized trial.
Three respiratory intensive care units.
Intubated patients with chronic obstructive pulmonary disease and acute hypercapnic respiratory failure.
A T-piece weaning trial was attempted 48 hours after intubation. If this failed, two methods of weaning were compared: 1) extubation and application of noninvasive pressure support ventilation by face mask and 2) invasive pressure support ventilation by an endotracheal tube.
Arterial blood gases, duration of mechanical ventilation, time in the intensive care unit, occurrence of nosocomial pneumonia, and survival at 60 days.
At admission, all patients had severe hypercapnic respiratory failure (mean pH, 7.18+/-0.06; mean PaCO2, 94.2+/-24.2 mm Hg), sensory impairment, and similar clinical characteristics. At 60 days, 22 of 25 patients (88%) who were ventilated noninvasively were successfully weaned compared with 17 of 25 patients (68%) who were ventilated invasively. The mean duration of mechanical ventilation was 16.6+/-11.8 days for the invasive ventilation group and 10.2+/-6.8 days for the noninvasive ventilation group (P = 0.021). Among patients who received noninvasive ventilation, the probability of survival and weaning during ventilation was higher (P = 0.002) and time in the intensive care unit was shorter (15.1+/-5.4 days compared with 24.0+/-13.7 days for patients who received invasive ventilation; P = 0.005). Survival rates at 60 days differed (92% for patients who received noninvasive ventilation and 72% for patients who received invasive ventilation; P = 0.009). None of the patients weaned noninvasively developed nosocomial pneumonia, whereas 7 patients weaned invasively did.
Noninvasive pressure support ventilation during weaning reduces weaning time, shortens the time in the intensive care unit, decreases the incidence of nosocomial pneumonia, and improves 60-day survival rates.
慢性阻塞性肺疾病急性加重期患者常需机械通气。这些患者撤机失败率高，机械通气时间延长会增加插管相关并发症。
确定无创通气是否能改善有创机械通气的撤机结局。
多中心随机试验。
三个呼吸重症监护病房。
插管的慢性阻塞性肺疾病合并急性高碳酸血症呼吸衰竭患者。
插管48小时后尝试进行T管撤机试验。若失败，则比较两种撤机方法：1）拔管并通过面罩应用无创压力支持通气；2）通过气管内导管进行有创压力支持通气。
动脉血气、机械通气时间、重症监护病房停留时间、医院获得性肺炎的发生情况以及60天生存率。
入院时，所有患者均有严重的高碳酸血症呼吸衰竭（平均pH值7.18±0.06；平均动脉血二氧化碳分压94.2±24.2 mmHg）、感觉障碍且临床特征相似。60天时，25例接受无创通气的患者中有22例（88%）成功撤机，而25例接受有创通气的患者中有17例（68%）成功撤机。有创通气组的机械通气平均时间为16.6±11.8天，无创通气组为10.2±6.8天（P = 0.021）。在接受无创通气的患者中，通气期间存活和撤机的概率更高（P = 0.002），重症监护病房停留时间更短（无创通气患者为15.1±5.4天，有创通气患者为24.0±13.7天；P = 0.005）。60天生存率有所不同（无创通气患者为92%，有创通气患者为72%；P = 0.009）。接受无创撤机的患者均未发生医院获得性肺炎，而接受有创撤机的患者中有7例发生。
撤机期间的无创压力支持通气可缩短撤机时间、缩短重症监护病房停留时间、降低医院获得性肺炎的发生率并提高60天生存率。
