Hörmann C, Baum M, Luz G, Putensen C, Putz G
Clinic for Anesthesia and Intensive Care Medicine, University of Innsbruck, Austria.
Intensive Care Med. 1992;18(4):226-30. doi: 10.1007/BF01709837.
The objective of this study was to evaluate the influence of different PSV levels on VT, F, VO2 in the early weaning phase of patients without chronic obstructive pulmonary disease. These parameters were tested for the predictive power for the success of the weaning. Patients on SIMV were studied during the first weaning attempt with PSV. Depending on their ventilatory support demands after 24 h they were divided into responders (patients breathing on CPAP) and nonresponders (patients being on a more invasive ventilatory mode). 14 ICU patients without pre-existing pulmonary disease being ventilated for at least 3 days entered the study. 2 of them could be studied a second time after failing the first weaning attempt. Beside the level of ventilatory support no other changes (drugs, nutrition) were allowed. VO2, VT, F were measured by a computer controlled, metabolic unit connected to the expiratory port of a Siemens Servo Ventilator. In addition, airway pressures, arterial pressure and heart rate were recorded. The measurements were performed at PSV of 5, 10 and 20 cmH2O. Arterial blood-gases were drawn at the end of each 60 min lasting PS period. Responders and nonresponders could be separated by the response of VO2, VT and F to a change in PS 10 to PS 20 cmH2O. Patients who significantly increased VT and significantly decreased F did not fulfil our weaning criteria. Our responders did not show a significant change in these two parameters, but a significant increase in VO2 at PS 20 cmH2O could be observed.(ABSTRACT TRUNCATED AT 250 WORDS)
本研究的目的是评估不同压力支持通气（PSV）水平对无慢性阻塞性肺疾病患者早期撤机阶段的潮气量（VT）、呼吸频率（F）、氧耗量（VO₂）的影响。对这些参数进行测试，以判断其对撤机成功的预测能力。在首次使用PSV进行撤机尝试期间，对采用同步间歇指令通气（SIMV）的患者进行研究。根据24小时后他们对通气支持的需求，将其分为反应者（使用持续气道正压通气（CPAP）呼吸的患者）和无反应者（使用更具侵入性通气模式的患者）。14名既往无肺部疾病且已通气至少3天的重症监护病房（ICU）患者进入研究。其中2名患者在首次撤机尝试失败后可进行第二次研究。除通气支持水平外，不允许有其他变化（药物、营养）。VO₂、VT、F由连接到西门子Servo呼吸机呼气端口的计算机控制代谢单元测量。此外，记录气道压力、动脉压和心率。测量在PSV为5、10和20 cmH₂O时进行。在每次持续60分钟的PS期结束时采集动脉血气。反应者和无反应者可通过VO₂、VT和F对PS从10 cmH₂O变为20 cmH₂O的反应来区分。潮气量显著增加且呼吸频率显著降低的患者未达到我们的撤机标准。我们的反应者在这两个参数上没有显著变化，但在PS为20 cmH₂O时可观察到氧耗量显著增加。（摘要截断于250字）
