Putensen C, Zech S, Wrigge H, Zinserling J, Stüber F, Von Spiegel T, Mutz N
Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Bonn, Germany.
Am J Respir Crit Care Med. 2001 Jul 1;164(1):43-9. doi: 10.1164/ajrccm.164.1.2001078.
Improved gas exchange has been observed during spontaneous breathing with airway pressure release ventilation (APRV) as compared with controlled mechanical ventilation. This study was designed to determine whether use of APRV with spontaneous breathing as a primary ventilatory support modality better prevents deterioration of cardiopulmonary function than does initial controlled mechanical ventilation in patients at risk for acute respiratory distress syndrome (ARDS). Thirty patients with multiple trauma were randomly assigned to either breathe spontaneously with APRV (APRV Group) (n = 15) or to receive pressure-controlled, time-cycled mechanical ventilation (PCV) for 72 h followed by weaning with APRV (PCV Group) (n = 15). Patients maintained spontaneous breathing during APRV with continuous infusion of sufentanil and midazolam (Ramsay sedation score [RSS] of 3). Absence of spontaneous breathing (PCV Group) was induced with sufentanil and midazolam (RSS of 5) and neuromuscular blockade. Primary use of APRV was associated with increases (p < 0.05) in respiratory system compliance (CRS), arterial oxygen tension (PaO2), cardiac index (CI), and oxygen delivery (DO2), and with reductions (p < 0.05) in venous admixture (QVA/QT), and oxygen extraction. In contrast, patients who received 72 h of PCV had lower CRS, PaO2, CI, DO2, and Q VA/Q T values (p < 0.05) and required higher doses of sufentanil (p < 0.05), midazolam (p < 0.05), noradrenalin (p < 0.05), and dobutamine (p < 0.05). CRS, PaO2), CI and DO2 were lowest (p < 0.05) and Q VA/Q T was highest (p < 0.05) during PCV. Primary use of APRV was consistently associated with a shorter duration of ventilatory support (APRV Group: 15 +/- 2 d [mean +/- SEM]; PCV Group: 21 +/- 2 d) (p < 0.05) and length of intensive care unit (ICU) stay (APRV Group: 23 +/- 2 d; PCV Group: 30 +/- 2 d) (p < 0.05). These findings indicate that maintaining spontaneous breathing during APRV requires less sedation and improves cardiopulmonary function, presumably by recruiting nonventilated lung units, requiring a shorter duration of ventilatory support and ICU stay.
与控制机械通气相比，气道压力释放通气（APRV）用于自主呼吸时可观察到气体交换改善。本研究旨在确定对于有急性呼吸窘迫综合征（ARDS）风险的患者，以APRV自主呼吸作为主要通气支持模式是否比初始控制机械通气能更好地预防心肺功能恶化。30例多发伤患者被随机分为两组，一组采用APRV自主呼吸（APRV组）（n = 15），另一组接受压力控制、时间切换的机械通气（PCV）72小时，随后采用APRV撤机（PCV组）（n = 15）。APRV期间，患者持续输注舒芬太尼和咪达唑仑以维持自主呼吸（ Ramsay镇静评分[RSS]为3分）。PCV组通过舒芬太尼、咪达唑仑（RSS为5分）和神经肌肉阻滞剂诱导无自主呼吸。APRV作为主要通气模式与呼吸系统顺应性（CRS）、动脉血氧分压（PaO2）、心脏指数（CI）和氧输送（DO2）增加（p < 0.05）以及静脉血掺杂（QVA/QT）和氧摄取减少（p < 0.05）相关。相比之下，接受72小时PCV的患者CRS、PaO2、CI、DO2和QVA/QT值较低（p < 0.05）并且需要更高剂量的舒芬太尼（p < 0.05）、咪达唑仑（p < 0.05）、去甲肾上腺素（p < 0.05）和多巴酚丁胺（p < 0.05）。PCV期间CRS、PaO2、CI和DO2最低（p < 0.05），QVA/QT最高（p < 0.05）。APRV作为主要通气模式始终与通气支持时间缩短相关（APRV组：15±2天[平均值±标准误]；PCV组：21±2天）（p < 0.05）以及重症监护病房（ICU）住院时间缩短相关（APRV组：23±2天；PCV组：30±2天）（p < 0.05）。这些结果表明，APRV期间维持自主呼吸所需的镇静较少，并且可能通过募集未通气的肺单位改善心肺功能，从而缩短通气支持时间和ICU住院时间。
