Discussion
gastrointestinal diseases, postoperative pulmonary complications, intraoperative pulmonary edema, gastrointestinal disease, edema
GASTROINTESTINAL DISEASES, GASTROINTESTINAL DISEASE, EDEMA, PULMONARY COMPLICATIONS, EXTRAVASATION
This study shows that COP- and SVV-based GDT protocols can more accurately improve intraoperative pulmonary edema, lowering the incidence of postoperative pulmonary complications of major abdominal surgery. Importantly, intraoperative COP- and SVV-based GDT reduced postoperative pulmonary complications of grade 2 and higher severity, which contributed to improving the outcome of major abdominal surgery, and conducive to shortening postoperative hospital stay (Table Some studies have shown that perioperative GDT seems to be more beneficial for patients with higher surgical risk [Therefore, for patients during major abdominal surgery, the perioperative GDT involves not only the maintenance of effective circulating blood volume but also the water balance inside and outside blood vessels. It is important to choose the right type of liquid and reduce the amount of intraoperative fluid infusion and tissue edema by using a reasonable amount of fluid according to the dynamic parameters. According to theoretical analysis, COP is important for maintaining patient fluid balance by influencing fluid flow in and out of blood vessels, according to Starling’s equation. It can more accurately monitor tissue perfusion status.Studies have shown that increased microvascular permeability in older patients with gastrointestinal diseases leads to extravasation of fluid and protein into the alveoli [In addition, recent studies have shown that the release of several inflammatory mediators caused by gastrointestinal disease and its correlative excessive COP lead to the degradation of endothelial glycocalyx [Furthermore, research shows that GDT based on a combination of dynamic indicators of liquid reactivity and other optimized parameters was more accurate than that based on dynamic indicators alone [Nevertheless, the type and timing of fluid infusion may be important, as we see in Table Our study has some limitations. First, COP and SVV were monitored only intraoperatively. GDT should be administered throughout the perioperative period, which may lead to more dramatic improvements in patient recovery. Second, this is a single-center study, and multicenter studies may reduce research errors and make the results more accurate. Third, some factors, such as dietary habits, may affect the accuracy of the results, although we have tried to account for many potential confounders in the experiment.Future research may focus on the influence of the timing of infusion of different fluid types on the COP to further uncover the qualitative and quantitative influence of fluid types and use timing on microcirculatory perfusion and tissue edema.