肺复张策略在全麻术后发生急性呼吸窘迫综合征肥胖患者中的应用

Effects of lung recruitment maneuver on fat patients with acute respiratory distress syndromes after general anesthesia

目的探讨在全麻术后发生急性呼吸窘迫综合征（ARDS）肥胖患者中应用肺复张法（LRM）治疗对氧合、呼吸力学参数及预后的影响。方法选取我院ICU2005—01-2008-04收治的外科全麻术后发生ARDS的肥胖患者32例，随机分为对照组（n=14）和肺复张组（n=18），两组基本通气模式均采用双相气道正压通气（BiPAP）；复张方法：BiPAP模式下将高压与低压均调为30-40cmH2O，维持20～50s完成肺复张。分别观察两组患者动脉血气分析、呼吸力学参数和预后指标，比较两组上述参数的差异。结果复张组氧合指数与对照组比较从12h起开始有明显改善，差异有统计学意义（P〈0．05），24、72h也均维持在较高数值。对照组氧合指数改善的时间较晚达72h。对照组存在CO2的轻度潴留，复张组无明显的CO2潴留。呼吸力学指标改变各组间差异无统计学意义（P〉0．05）。两组间28d病死率差异无统计学意义（P〉0．05）。复张组机械通气时间和住ICU时间较对照组明显缩短（P〈0．05）。结论LRM可以显著改善全麻术后发生ARDS肥胖患者的氧合，较早开放萎陷的肺泡，明显缩短机械通气时间和住ICU时间。

Objective To evaluate the effects of lung recruitment maneuver（ RM ） on fat patients with acute respiratory distress syndromes （ ARDS ） after general anesthesia. Methods 32 fat patients with ARDS after general anesthesia were assigned into two groups at random. All the patients were ventilated with bi -phasic positive airway pressure. Lung RM were carried out by making Plow and Phigh equal and keeping them 30 -40 cmH2O for 20 -50 s, repeated every 8 hours during the first 3 days. Both physiological data and the prognosis, including arterial blood gas （ PaO2 , PaCO2 ） , airway pressure （ peak pressure, plateau pressure ） , ventilator settings （ tidal volume, PEEP, FiO2 ） , hemodynamie parameters, the days in ICU, the days of mechanical ventilation and 28 - day mortality were compared between 2 groups. Results The PaO2/FiO2 increased after lung RM at 12 hour, but it began to increase at 72 hour in the patients without RM. There was significant difference in changes of PaO2/FiO2 between two groups at hour 12, 24 and 72. So was PaCO2. During the first 3 days, the patients without RM had higher level of PaCO2 than patients with RM. No differences in peak pressure and plateau pressure between 2 groups were found during the first 3 days. There were obvious differences on the days in ICU and the days of mechanical ventilation, but there was no difference on 28 - day mortality between 2 groups. Conclusion Lung RM is safe and effective method in improving oxygenation of the fat patients with acute respiratory distress syndromes after general anesthesia and has a great impacts on the prognosis. It could shorten the days of mechanical ventilation and the days in ICU for the patients with ARDS.