保守氧疗法在重症肺炎机械通气患者中的应用效果观察

Observation of the curative effect of conservative oxygen therapy in mechanical ventilation of patients with severe pneumonia

目的比较保守氧疗和常规氧疗对重症肺炎机械通气支持患者疗效的差异,并观察不同氧疗模式对患者预后的影响。方法采用前瞻性随机对照研究方法,选择2019年5月至2021年5月入住合肥市第一人民医院重症监护病房(ICU)需要机械通气支持的110例重症肺炎患者,按随机数字表法将患者分为常规氧疗组(51例)和保守氧疗组(55例)。两组患者均采用有创-无创序贯通气策略,常规氧疗组氧疗目标设置为动脉血氧分压〔PaO2>150 mmHg(1 mmHg=0.133 kPa)〕或脉搏血氧饱和度(SpO2)>0.96。保守氧疗组设置PaO2在70~100 mmHg或SpO2在0.90~0.92。观察两组患者治疗前后血气分析指标、机械通气时间、ICU住院时间、ICU病死率和入院后超过48 h新发器官功能障碍及感染发生率变化;采用Kaplan-Meier法分析两组累积生存率的差异。结果两组治疗后pH值、PaO2、氧合指数(PaO2/FiO2)均较治疗前明显升高,动脉血二化碳氧分压(PaCO2)较治疗前明显降低,且治疗后保守氧疗组pH值明显高于常规氧疗组(7.4±0.1比7.3±0.3),PaO2、PaCO2、PaO2/FiO2均明显低于常规氧疗组〔PaO2(mmHg):68.9±4.7比75.2±6.0,PaCO2(mmHg):42.1±5.6比50.5±7.5,PaO2/FiO2(mmHg):329±126比365±108〕,差异均有统计学意义(均P<0.05)。保守氧疗组机械通气时间较常规氧疗组明显延长(d:19.7±3.5比13.9±4.5,P<0.05),但保守氧疗组和常规氧疗组患者ICU住院时间比较差异无统计学意义(d:26.5±5.0比25.5±4.6,P>0.05)。与常规氧疗组比较,保守氧疗组ICU病死率和院内新发血流感染发生率及并发肝功能不全、休克、ICU获得性衰弱(ICUAW)发生率均明显降低〔ICU病死率:27.3%(15/55)比45.1%(23/51),肝功能不全:1.8%(1/55)比7.8%(4/51),休克:3.6%(2/55)比9.8%(5/51),ICUAW:5.5%(3/55)比11.8%(6/51),新发血流感染:5.5%(3/55)比11.8%(6/51),均P<0.05〕。Kaplan-Meier分析显示,保守氧疗组60 d累积生存率明显高于常规氧疗组(72.7%比54.9%;Log-Rank检验:χ2=4.244,P=0.039)。结论保守氧疗可以降低重症肺炎患者ICU病死率及并发休克、肝功能不全、ICUAW和血流感染发生率,但延长了机械通气时间。

Objective To compare the effects of conservative oxygen therapy and conventional oxygen therapy on the efficacy and prognosis of mechanical ventilation support in patients with severe pneumonia.Methods A prospective randomized controlled study were conducted,110 patients with severe pneumonia requiring mechanical ventilation in intensive care unit(ICU)of Hefei First People's Hospital from May 2019 to May 2021 were selected and divided into conventional oxygen therapy group(51 cases)and conservative oxygen therapy group(55 cases)according to random number table method.Patients in both groups were treated with invasive to non-invasive sequential mechanical ventilation strategy,and the target of oxygen therapy in the conventional oxygen therapy group was set as the arterial partial pressure of oxygen(PaO2)>150 mmHg(1 mmHg=0.133 kPa)or pulse oxygen saturation(SpO2)>0.96.In the conservative oxygen therapy group,PaO2 was set at 70-100 mmHg or SpO2 at 0.90-0.92.The changes of blood gas analysis,mechanical ventilation time,ICU stay time,ICU mortality,new organ dysfunction and infection more than 48 hours after admission were observed in two groups before and after treatment.Kaplan-Meier method was used to analyze the difference in cumulative survival rate between the two groups.Results After treatment,pH value,PaO2 and oxygenation index(PaO2/FiO2)in both groups were significantly higher than before treatment,and arterial partial pressure of carbon dioxide(PaCO2)was significantly lower than before treatment.pH value in the conservative oxygen therapy group was significantly higher than that in the conventional oxygen therapy group(7.4±0.1 vs.7.3±0.3).PaO2,PaCO2 and PaO2/FiO2 were significantly lower than those in conventional oxygen therapy group[PaO2(mmHg):68.9±4.7 vs.75.2±6.0,PaCO2(mmHg):42.1±5.6 vs.50.5±7.5,PaO2/FiO2(mmHg):329±126 vs.365±108,all P<0.05].The mechanical ventilation time in the conservative oxygen therapy group was significantly longer than that in the conventional oxygen therapy group(days:19.7±3.5 vs.13.9±4.5,P<0.05),but there was no significant difference in ICU hospitalization time between the conservative oxygen therapy group and the conventional oxygen therapy group(days:26.5±5.0 vs.25.5±4.6,P>0.05).Compared with the conventional oxygen therapy group,the ICU mortality,the incidence of nosocomial bloodstream infection,and the incidence of liver insufficiency,shock,and ICU acquired weakness(ICUAW)were decreased significantly in the conservative oxygen therapy group[ICU mortality:27.3%(15/55)vs.45.1%(23/51),liver insufficiency:1.8%(1/55)vs.7.8%(4/51),shock:3.6%(2/55)vs.9.8%(5/51),ICUAW:5.5%(3/55)vs.11.8%(6/51),the incidence of new bloodstream infection:5.5%(3/55)vs.11.8%(6/51),all P<0.05].Kaplan-Meier analysis showed that the cumulative survival rate of the conservative oxygen therapy group was significantly higher than that of the conventional oxygen therapy group(72.7%vs.54.9%;Log-Rank test:χ2=4.244,P=0.039).Conclusion Conservative oxygen therapy can reduce ICU mortality,the incidence of shock,liver insufficiency,ICUAW,and bloodstream infection in patients with severe pneumonia,but prolong mechanical ventilation time.