Department of Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, China.
BMC Pulm Med. 2022 Nov 4;22(1):400. doi: 10.1186/s12890-022-02194-6.
Associated with increased morbidity and mortality, postoperative pulmonary complications (PPCs) often occur after major abdominal surgery. Diaphragmatic dysfunction is suggested to play an important role in the development of PPCs and diaphragm echodensity can be used as an indicator of diaphragm function. This study aimed to determine whether diaphragm echodensity could predict the occurrence of PPCs in patients after major abdominal surgery.
Diaphragm ultrasound images of patients after major abdominal surgery were collected during spontaneous breathing trials. Echodensity was quantified based on the right-skewed distribution of grayscale values (50th percentile, ED50; 85th percentile, ED85; mean, EDmean). Intra- and inter-analyzer measurement reproducibility was determined. Outcomes including occurrence of PPCs, reintubation rate, duration of ventilation, and length of ICU stay were recorded.
Diaphragm echodensity was measured serially in 117 patients. Patients who developed PPCs exhibited a higher ED50 (35.00 vs. 26.00, p < 0.001), higher ED85 (64.00 vs. 55.00, p < 0.001) and higher EDmean (39.32 vs. 33.98, p < 0.001). In ROC curve analysis, the area under the curve of ED50 for predicting PPCs was 0.611. The optimal ED50 cutoff value for predicting the occurrence of PPCs was 36. According to this optimal ED50 cutoff value, patients were further divided into a high-risk group (ED50 > 36, n = 35) and low-risk group (ED50 ≤ 36, n = 82). Compared with the low-risk group, the high-risk group had a higher incidence of PPCs (unadjusted p = 0.003; multivariate-adjusted p < 0.001).
Diaphragm echodensity can be feasibly and reproducibly measured in mechanically ventilated patients. The increase in diaphragm echodensity during spontaneous breathing trials was related to an increased risk of PPCs in patients after major abdominal surgery.
术后肺部并发症（PPCs）与发病率和死亡率增加有关，常发生在大腹部手术后。膈肌功能障碍被认为在 PPCs 的发展中起重要作用，膈肌回声密度可用作膈肌功能的指标。本研究旨在确定大腹部手术后患者的膈肌回声密度是否可预测 PPCs 的发生。
在自主呼吸试验期间收集大腹部手术后患者的膈肌超声图像。基于灰度值的右偏分布（第 50 百分位数，ED50；第 85 百分位数，ED85；平均值，EDmean）来量化回声密度。确定了内和分析仪测量的可重复性。记录了包括 PPCs 发生、再插管率、通气时间和 ICU 住院时间在内的结果。
117 例患者连续测量了膈肌回声密度。发生 PPCs 的患者 ED50 更高（35.00 比 26.00，p<0.001）、ED85 更高（64.00 比 55.00，p<0.001）和 EDmean 更高（39.32 比 33.98，p<0.001）。在 ROC 曲线分析中，ED50 预测 PPCs 的曲线下面积为 0.611。预测 PPCs 发生的最佳 ED50 截断值为 36。根据该最佳 ED50 截断值，患者进一步分为高危组（ED50>36，n=35）和低危组（ED50≤36，n=82）。与低危组相比，高危组 PPCs 的发生率更高（未调整 p=0.003；多变量调整 p<0.001）。
在机械通气患者中可以可行且可重复地测量膈肌回声密度。自主呼吸试验期间膈肌回声密度的增加与大腹部手术后患者 PPCs 风险增加有关。
