Heparin versus normal saline locking for prevention of occlusion, catheter-related infections and thrombosis in central venous catheter in adults: Overview of systematic reviews

Venous access devices are used in health care. To prevent occlusions the evidence confirmed the need for routine catheter flushing before and after infusion as well as at the end of use. To date, the efficacy of heparin has not been demonstrated. The aim of this study was to evaluate the effectiveness of the locking of central venous catheters with heparin versus normal saline in adults to prevent occlusion, catheter-related infections and thrombosis in adults. A literature search using Medline, Embase, Cochrane Library and Cinahl was performed to identify all meta-analyses addressing the effectiveness of heparin versus normal saline in locking central venous catheters in adults. Four reviewers independently selected publications assessed quality and extracted data. Parameter estimates regarding occlusion, catheter- related infections and thrombosis were pooled using an umbrella review. We identified 6356 references. Seven systematic reviews were included in the study. Most of the studies included in the systematic reviews were conducted in oncohaematology departments, intensive care and cardiac surgery units among patients with multiple diseases and chronicity. Most studies report a heparin concentration of 10 to 5000 IU/ml versus normal saline and other solutions. There was no evidence that heparin was more effective than normal saline in reducing complications such as occlusion, catheter-related infections and thrombosis. No statistically significant difference was found between heparin and normal saline in reducing catheter occlusion. Heparin is not superior compared to normal saline.