Efficacy and safety of the use of heparin as thromboprophylaxis in patients with liver cirrhosis: A systematic review and meta-analysis

IntroductionVenous thromboembolism is a common cause of morbidity and mortality. Although cirrhosis has classically been considered as an acquired bleeding diathesis, there is increasing evidence that rejects the traditional belief that these patients are naturally protected against venous thromboembolism. However, antithrombotic prophylaxis in this setting is still underused. The aim of this review is to assess if the use of heparin in cirrhotic patients is effective in the prevention of venous thromboembolism and whether its use is related to an increase in bleeding episodes.Material and methodsWe searched in MEDLINE and EMBASE, using the terms "liver cirrhosis", "heparin", "low molecular weight heparin," "venous thrombosis", "deep venous thrombosis", "hemorrhage" and "bleeding”. We sought for clinical trials and observational studies performed in patients with liver cirrhosis to evaluate the efficacy or the safety of the heparin. It was used the Mantel-Haenszel method with a random effects model. Odd Ratio was the main measure of effect. The results of the pooled OR and its 95% confidence intervals were expressed in forest plots. The heterogeneity was assessed by the I2 statistic. The statistical software RevMan was used.Results and conclusionsThe current review found that, although the use of heparin was not related to higher rates of bleeding in cirrhotic patients (pooled OR 0.87 95% CI (0.34-2.18)), it doesn´t decrease the risk of venous thromboembolism in patients receiving prophylaxis, with a pooled OR 1.65 95% (0.36 to 7.54). However, further prospective studies are needed to assess this issue.