医用气体工程

目的：探讨循环氧代谢指标[中心静脉血氧饱和度(ScvO₂)、静脉-动脉二氧化碳分压差(P(v-a)CO₂)]与超声指标(下腔静脉宽度及变异度、心脏功能参数、肺部B线)在脓毒性休克患者容量管理中的应用价值及相关性，以优化液体复苏策略。方法：选取益阳市中心医院2023-01至2025-03收治的180例脓毒性休克患者(血乳酸> 4 mmol/L)，按氧代谢指标(ScvO₂、P(v-a)CO₂)分为4组(A-D组)，按超声指标(下腔静脉宽度及变异度)分为6组(E-J组)。所有患者均接受液体复苏治疗，以氧代谢达标(ScvO₂ > 70%、P(v-a)CO₂<6 mmHg)和超声达标(下腔静脉宽度> 20 mm、变异度<50%)为终点，记录(复苏前及复苏后24 h)的指标变化，比较输液总量、肺水肿发生率及指标相关性。结果：A组(ScvO₂<70%、P(v-a)CO₂ > 6 mmHg)复苏后下腔静脉变异度显著降低(P<0.05)，心脏指数(CI)、心输出量(CO)显著升高(P<0.05);D组(ScvO₂ > 70%、P(v-a)CO₂<6mmHg)肺水肿发生率最低(8.33%)。E组(下腔静脉宽度<10 mm、变异度> 50%)复苏后ScvO₂显著升高(P<0.05),P(v-a)CO₂显著降低(P<0.05);J组(下腔静脉宽度> 20 mm、变异度<50%)氧代谢达标率最高(91.67%)。同时参考氧代谢与超声指标的患者输液总量更少(P<0.05)，肺水肿发生率显著低于单一指标组(P<0.05)。复苏后6～12 h，氧代谢与超声指标的一致性达78.33%，且与器官功能恢复评分(SOFA)呈负相关(r=-0.421,P<0.01)。结论：循环氧代谢指标与超声指标在脓毒性休克容量管理中具有互补性，联合监测可优化液体复苏策略，减少过量补液风险，改善患者预后。

Objective: To explore the application value and correlation of circulating oxygen metabolism indicators [(central venous oxygen saturation(ScvO₂), venous-to-arterial carbon dioxide partial pressure difference(P(v-a)CO₂)] and ultrasound indicators(inferior vena cava width and variability, cardiac function parameters, and lung B-line) in volume management of patients with septic shock, so as to optimize fluid resuscitation strategies. Methods: A total of 180 patients with septic shock(blood lactate>4 mmol/L) admitted to Yiyang Central Hospital from January 2023 to March 2025 were selected and divided into 4 groups(A-D groups) based on oxygen metabolism indicators(Scv O₂, P(v-a) CO₂) and 6 groups(E-J groups) based on ultrasound indicators(inferior vena cava width and variability). All patients received fluid resuscitation treatment, with oxygen metabolism reaching the standard(ScvO₂>70%, P(v-a) CO₂<6 mmHg) and ultrasound reaching the standard(inferior vena cava width>20 mm, variability<50%) as endpoints. Changes in indicators(before and 24 h after resuscitation) were recorded, and the total amount of infusion, incidence of pulmonary edema, and correlation between indicators were compared. Results: After resuscitation, inferior vena cava variability in Group A(ScvO₂<70%, P(v-a)CO₂>6 mmHg) significantly decreased(P<0.05), while the cardiac index(CI) and cardiac output(CO) significantly increased(P<0.05). Group D(ScvO₂>70%, P(v-a)CO₂<6 mmHg) had the lowest incidence of pulmonary edema(8.33%). After resuscitation, ScvO₂ significantly increased(P<0.05) and P(v-a)CO₂ significantly decreased(P<0.05) in group E(inferior vena cava width<10 mm, variability>50%). Group J(inferior vena cava width>20 mm, variability<50%) had the highest oxygen metabolism compliance rate(91.67%). Patients who referred to both oxygen metabolism and ultrasound indicators had a lower total volume of infusion(P<0.05) and a significantly lower incidence of pulmonary edema compared to the single indicator group(P<0.05). After 6-12 h of resuscitation, the consistency between oxygen metabolism and ultrasound indicators reached 78.33%, and was negatively correlated with Sequential Organ Failure Assessment(SOFA)(r=-0.421, P<0.01). Conclusion: Circulating oxygen metabolism indicators and ultrasound indicators complement each other in volume management of septic shock. Combined monitoring can optimize fluid resuscitation strategies, reduce the risk of excessive fluid replacement, and improve patient prognosis.