[Meta-analysis of the impact of continuous anticoagulation therapy with low-dose heparin or low molecular weight heparin on the prognosis of patients with acute respiratory distress syndrome].

OBJECTIVE

The effects of low-dose heparin and low molecular weight heparin on the efficacy and prognosis of patients with acute respiratory distress syndrome (ARDS) were systematically evaluated.

METHODS

Chinese and English databases such as Wanfang data, VIP database, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Service system (SinoMed), American National Medical Library database (PubMed), Netherlands Medical Abstracts database (Embase) and Cochrane library database were searched for the randomized controlled trials (RCTs) of heparin or low molecular weight heparin in the treatment of ARDS. The search time is from July 1999 to June 2020. The control group was given routine treatment, while the experimental group was given heparin 5-10 U×kg×h, or low molecular heparin subcutaneous injected 2 500-5 000 U once every 12 hours for 7 days on the basis of the routine treatment. The main outcome were 28-day mortality, arterial oxygen saturation (SaO), acute physiology and chronic health evaluation II (APACHE II), length of stay in (intensive care unit) ICU and mechanical ventilation time, and the secondary outcome indexes were C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), lung injury score, respiratory frequency, activated partial thromboplastin time (APTT) and prothrombin time (PT) after 7 days' treatment. The two researchers collected data and evaluated the quality of the literature according to the Cochrane 5.1. The stability of the Meta-analysis results was tested by sensitivity analysis, and the publication bias was included in the funnel chart analysis.

RESULTS

Fourteen Chinese literatures were included, with a total of 894 cases, including 454 cases in the experimental group and 440 cases in the control group. The results of Meta-analysis showed that the 28-day fatality rate in the experimental group was significantly lower than that in the control group [relative risk (RR) = 0.54, 95% confidence interval (95%CI) was 0.38-0.76, P = 0.000 4], and 7-day SaO significantly increased [heparin: mean difference (MD) = 48.27, 95%CI was 29.95-66.59, P < 0.000 01]. Low molecular weight heparin: MD = 56.67, 95%CI was 41.22-71.13, P < 0.000 01]. Compared with the control group, the APACHE II score (MD = -4.28, 95%CI was -5.15 to -3.42, P < 0.000 01), the lung injury score (MD = -1.19, 95%CI was -1.35 to -1.03, P < 0.000 01) and the respiratory rate (MD = -4.76, 95%CI was -6.26 to -3.26, P < 0.000 01) in the experimental group were significantly lower than those in the control group after 7 days' treatment. The time of staying in ICU (MD = -4.85, 95%CI was -6.94 to -2.76, P < 0.000 01) and the time of mechanical ventilation (MD = -2.93, 95%CI was -3.34 to -2.52, P < 0.000 01) in the experimental group were lower than those in the control group. After 7 days' treatment, the levels of IL-6 (MD = -38.50, 95%CI was -59.01 to -17.99, P < 0.000 01), TNF-α (MD = -16.24, 95%CI was -31.11 to -1.38, P < 0.000 01) and CRP (MD = -5.5, 95%CI was -6.47 to -4.27, P < 0.000 01) were significantly lower in the experimental group than those in the control group. However, after 7 days' treatment, there were no significant differences in APTT (MD = -0.55, 95%CI was -1.61 to 0.51, P = 0.27) or PT (MD = -0.41, 95%CI was -1.48 to 0.66, P = 0.45). For the indicators with high heterogeneity, Meta-analysis was carried out again by excluding any study, and the overall effect value did not change significantly, suggesting that the results were relatively robust. Funnel chart analysis was carried out on the indexes with more than 10 articles included in the literature. The results showed that the literature had publication bias, but the bias was small.

CONCLUSIONS

Continuous anticoagulation therapy with low dose heparin and low molecular weight heparin can improve the prognosis and reduce the mortality of patients with ARDS.