Erland Östberg, Alexander Larsson, Philippe Wagner, Staffan Eriksson, Lennart Edmark
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引用次数: 0
Abstract
Background: Positive end-expiratory pressure (PEEP) is important to increase lung volume and counteract airway closure during anaesthesia, especially in obese patients. However, maintaining PEEP during emergence preoxygenation might increase postoperative atelectasis by allowing susceptible lung areas to be filled with highly absorbable oxygen that gets entrapped when small airways collapse due to the sudden loss of PEEP at extubation.
Objective: This study aimed to test the hypothesis that withdrawing PEEP just before emergence preoxygenation would better maintain postoperative oxygenation.
Design: Prospective, randomised controlled trial.
Setting: Single centre secondary hospital in Sweden between December 2019 and January 2023.
Patients: A total of 60 patients, with body mass index between 35 and 50 kg m -2 , undergoing laparoscopic bariatric surgery.
Intervention: Intraoperative ventilation was the same for all patients with a fixed PEEP of 12 or 14 cmH 2 O depending on body mass index. No recruitment manoeuvres were used. After surgery, patients were allocated to maintained PEEP or zero PEEP during emergence preoxygenation.
Main outcome measures: The primary outcome was change in oxygenation from before awakening to 45 min postoperatively as measured by estimated venous admixture calculated from arterial blood gases.
Results: Both groups had impaired oxygenation postoperatively; in the group with PEEP maintained during awakening, estimated venous admixture increased by mean 9.1%, and for the group with zero PEEP during awakening, estimated venous admixture increased by mean 10.6%, difference -1.5% (95% confidence interval -4.6 to 1.7%), P = 0.354. Throughout anaesthesia, both groups exhibited low driving pressures and superior oxygenation compared with the awake state.
Conclusions: Withdrawing PEEP before emergence preoxygenation, did not alter early postoperative oxygenation in obese patients undergoing laparoscopic bariatric surgery. Intraoperative oxygenation was excellent despite using fixed PEEP and no recruitment manoeuvres, but deteriorated after extubation, indicating a need for future studies aimed at improving the emergence procedure.
Clinical trial number and registry: www.clinicaltrials.gov , NCT04150276. Registration date: 4 November 2019. Principal investigator: Erland Östberg.
背景:呼气末正压(PEEP)对于增加肺容量和抵消麻醉期间气道关闭非常重要,尤其是对于肥胖患者。然而,在起始预吸氧期间维持 PEEP 可能会增加术后失氧,因为拔管时 PEEP 的突然消失会导致小气道塌陷,从而使易感肺部区域充满被夹带的高吸收性氧气:本研究旨在验证以下假设:在起始预吸氧前撤出 PEEP 可更好地维持术后氧合:前瞻性随机对照试验:2019年12月至2023年1月期间,瑞典单中心二级医院:共 60 名患者,体重指数在 35 至 50 kg m-2 之间,接受腹腔镜减肥手术:所有患者的术中通气量相同,根据体重指数,固定 PEEP 为 12 或 14 cmH2O。不使用任何招募操作。手术后,患者被分配到维持 PEEP 或在起始预吸氧期间使用零 PEEP:主要结果为从苏醒前到术后 45 分钟内氧合状态的变化,通过动脉血气计算出的估计静脉混合物进行测量:两组患者术后氧合均受损;在苏醒期间保持 PEEP 的组别中,估计静脉掺入量平均增加了 9.1%,而在苏醒期间 PEEP 为零的组别中,估计静脉掺入量平均增加了 10.6%,差异为-1.5%(95% 置信区间-4.6 至 1.7%),P = 0.354。在整个麻醉过程中,与清醒状态相比,两组患者均表现出较低的驱动压力和较好的氧合:结论:在进行腹腔镜减肥手术的肥胖患者中,在起始预氧前撤除 PEEP 不会改变术后早期氧合。尽管使用了固定 PEEP 且未进行招募操作,但术中氧合状况良好,但拔管后氧合状况恶化,这表明今后有必要开展旨在改进骤醒程序的研究。临床试验编号和注册表:www.clinicaltrials.gov, NCT04150276。注册日期:2019 年 11 月 4 日。主要研究者:Erland Östberg:Erland Östberg.
期刊介绍:
The European Journal of Anaesthesiology (EJA) publishes original work of high scientific quality in the field of anaesthesiology, pain, emergency medicine and intensive care. Preference is given to experimental work or clinical observation in man, and to laboratory work of clinical relevance. The journal also publishes commissioned reviews by an authority, editorials, invited commentaries, special articles, pro and con debates, and short reports (correspondences, case reports, short reports of clinical studies).