RESUMO
Background: Application of individualized positive end-expiratory pressure (PEEP) based on minimum driving pressure facilitates to prevent from postoperative pulmonary complications (PPCs). Whether lung protective ventilation strategy can reduce the risk of PPCs in COVID-19 patients remains unclear. In this study, we compared the effects of driving pressure-guided ventilation with conventional mechanical ventilation on PPCs in patients with COVID-19. Methods: Patients infected COVID-19 within 30-day before surgery were retrospectively enrolled consecutively. Patients were divided into two group: driving pressure-guided lung protective ventilation strategy group (LPVS group) and conventional mechanical ventilation group (Control group). Propensity score matching for variables selected was used by logistic regression with the nearest-neighbor method. The outcomes were the incidence of PPCs and hypoxemia in post-anesthesia care unit. Results: There was no significant difference in the baseline data between both groups (P > 0.05). The incidence of PPCs (12.73 % vs 36.36 %, χ2 = 7.068, P = 0.008) and hypoxemia [18.18 % vs 38.18 %, χ2 = 4.492, P = 0.034], and lung ultrasound scores [4.68 ± 1.60 vs 8.39 ± 1.87, t = 8.383, P < 0.001] in LPVS group were lower than control group. The PEEP, airway pressure and plateau pressure in LPVS group were higher than control group, but driving pressure and tidal volume was lower than control group, the difference was statistically significant (P < 0.05). Conclusion: Individualized PEEP ventilation strategy guided by minimum driving pressure could improve oxygenation and reduce the incidence of PPCs in surgical patients with COVID-19.
RESUMO
OBJECTIVE: To evaluate the effects of ulinastatin (UTI) on lung injury induced by simultaneous pancreas-kidney transplantation in piglet. METHODS: With reproduction of simultaneous pancreas-kidney transplantation model in piglets, 12 couples of piglets were randomly divided into two groups (n=12). Piglets in UTI group were given a constant infusion of UTI 15 kU x kg(-1) x h(-1) by means of a pump during operation. Control group were treated with constant pumped infusion of 0.9% saline in equal volume. The blood samples were collected to measure the plasma concentrations of superoxide dismutase (SOD), malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-alpha) and interleukin-8 (IL-8) before operation (baseline levels, T0), at the time of re-establishment of circulation with successful an anastomosis of arteries and veins (T1), at 1 hour and 2 hours after re-establishment of circulation (T2 and T3), and at the end of operation (T4). The pathological changes in the lungs were examined. RESULTS: In control group, plasma MDA concentration was significantly increased from T1 till T4 as compared with T0 (all P<0.05), whereas in group UTI it did not change significantly (all P>0.05). In group UTI, SOD activity was significantly increased at T1-2 and T4 as compared with T0 (all P<0.05), whereas in control group it did not change significantly (all P>0.05). The plasma MDA concentration was significantly decreased at T1 and T2, and SOD activity was increased at T2 in group UTI than those in control group (all P<0.05). In control group, plasma TNF-alpha concentration was significantly increased from T2 to T4 as compared with T0 (all P<0.05), whereas it did not change significantly in group UTI (all P>0.05). The plasma IL-8 concentration was significantly decreased at T1-2 and T4 in group UTI compared with those in control group (both P<0.05). CONCLUSION: UTI can inhibit neutrophil aggregation in lungs and expression of harmful inflammatory cytokines, and it reduces production of oxygen free radical, so that it can protect lung tissue from injury induced by simultaneous pancreas-kidney transplantation.
