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Intraoperative lung-protective ventilation, including low tidal volume and positive end-expiratory pressure, reduces postoperative pulmonary complications. However, the effect and specific alveolar recruitment maneuver method are controversial. We investigated whether the intraoperative intermittent recruitment maneuver further reduced postoperative pulmonary complications while using a lung-protective ventilation strategy. Adult patients undergoing elective laparoscopic colorectal surgery were randomly allocated to the recruitment or control groups. Intraoperative ventilation was adjusted to maintain a tidal volume of 6–8 mL kg−1 and positive end-expiratory pressure of 5 cmH2O in both groups. The alveolar recruitment maneuver was applied at three time points (at the start and end of the pneumoperitoneum, and immediately before extubation) by maintaining a continuous pressure of 30 cmH2O for 30 s in the recruitment group. Clinical and radiological evidence of postoperative pulmonary complications was investigated within 7 days postoperatively. A total of 125 patients were included in the analysis. The overall incidence of postoperative pulmonary complications was not significantly different between the recruitment and control groups (28.1% vs. 31.1%, P = 0.711), while the mean ± standard deviation intraoperative peak inspiratory pressure was significantly lower in the recruitment group (10.7 ± 3.2 vs. 13.5 ± 3.0 cmH2O at the time of CO2 gas-out, P < 0.001; 9.8 ± 2.3 vs. 12.5 ± 3.0 cmH2O at the time of recovery, P < 0.001). The alveolar recruitment maneuver with a pressure of 30 cmH2O for 30 s did not further reduce postoperative pulmonary complications when a low tidal volume and 5 cmH2O positive end-expiratory pressure were applied to patients undergoing laparoscopic colorectal surgery and was not associated with any significant adverse events. However, the alveolar recruitment maneuver significantly reduced intraoperative peak inspiratory pressure. Further study is needed to validate the beneficial effect of the alveolar recruitment maneuver in patients at increased risk of postoperative pulmonary complications. Trial registration: Clinicaltrials.gov (NCT03681236).术中肺保护性通气（intraoperative lung-protective ventilation），即采用小潮气量联合呼气末正压（positive end-expiratory pressure, PEEP）的通气策略，可降低术后肺部并发症（postoperative pulmonary complications）的发生风险。然而，其具体临床疗效及肺泡复张手法（alveolar recruitment maneuver）的优选方案仍存在学术争议。本研究旨在探讨在已实施肺保护性通气策略的基础上，术中间歇性肺泡复张手法是否可进一步降低术后肺部并发症的发生率。 本研究将接受择期腹腔镜结直肠手术的成年患者随机分为复张组与对照组。两组术中通气参数均设置为潮气量6~8 mL·kg⁻¹、呼气末正压5 cmH₂O。复张组分别于气腹建立时、气腹解除时以及拔管前即刻三个时间点实施肺泡复张手法：维持持续气道压30 cmH₂O达30秒。 术后7天内，研究者对患者术后肺部并发症的临床及影像学证据进行了评估。本研究共纳入125例患者进行数据分析。结果显示，复张组与对照组的术后肺部并发症总发生率无显著统计学差异（28.1% vs 31.1%，P=0.711）；但在CO₂气腹排气时，复张组的术中平均值±标准差吸气峰压（peak inspiratory pressure）显著低于对照组（10.7±3.2 vs 13.5±3.0 cmH₂O，P<0.001）；复苏期吸气峰压亦显著低于对照组（9.8±2.3 vs 12.5±3.0 cmH₂O，P<0.001）。 对于接受腹腔镜结直肠手术的患者，在采用小潮气量联合5 cmH₂O呼气末正压的肺保护性通气策略基础上，施加30 cmH₂O持续30秒的肺泡复张手法并未能进一步降低术后肺部并发症的发生率，且未观察到显著不良事件。不过，该肺泡复张手法可显著降低术中吸气峰压。未来仍需开展进一步研究，以验证肺泡复张手法在术后肺部并发症高风险人群中的临床获益效果。 试验注册：Clinicaltrials.gov（NCT03681236）。