Effect of ultrasound-guided individualized positive end-expiratory pressure on the severity of postoperative atelectasis in elderly patients: a randomized controlled study

Postoperative pulmonary complications (PPCs) are common in patients undergoing general anesthesia, with atelectasis being a key contributor that increases postoperative mortality and prolongs hospitalization. Our research hypothesis is that ultrasound-guided individualized PEEP titration can reduce postoperative atelectasis. This single-center randomized controlled trial recruited elderly patients for laparoscopic surgery. Patients were randomly assigned to two group: the study group (individualized PEEP groups, PEEP Ind group) and the control group (Fixed PEEP group, PEEP 5 group). All patients in these two groups received volume-controlled ventilation during general anesthesia. Patients in the study group were given ultrasound-guided PEEP, while those in the control group were given a fixed 5 cmH₂O PEEP. Bedside ultrasound assessed lung ventilation. The primary outcome was the severity of atelectasis within seven days post-surgery. Eighty-nine patients scheduled for elective laparoscopic radical surgery for colorectal cancer were enrolled in our study. Lung ultrasound scores (LUSs) in the study group during postoperative seven days was significantly decreased compared with that in the control group (P < 0.05). The severity of postoperative atelectasis in the study group was significantly improved. The incidence of PPCs during postoperative 7 days in the study group was significantly less than that in the control group (48.6% vs. 77.8%; RR = 0.625; CI = 0.430-0.909; P = 0.01). In elderly patients undergoing laparoscopic radical resection, lung ultrasound-guided individualized PEEP can alleviate the severity of postoperative atelectasis.Clinical trial number and registry URL: No. ChiCTR2200062979 ( https://www.chictr.org.cn ).