Critical review and meta-analysis of spurious hemolysis in blood samples collected from intravenous catheters.

Background: A number of preanalytical activities strongly infl uence sample quality, especially those related to sample collection. Since blood drawing through intravenous catheters is reported as a potential source of erythrocyte injury, we performed a critical review and meta-analysis about the risk of catheter-related hemolysis. Materials and methods: We performed a systematic search on PubMed, Web of Science and Scopus to estimate the risk of spurious hemolysis in blood samples collected from intravenous catheters. A meta-analysis with calculation of Odds ratio (OR) and Relative risk (RR) along with 95% Confi dence interval (95% CI) was carried out using random eff ect mode. Results: Fifteen articles including 17 studies were fi nally selected. The total number of patients was 14,796 in 13 studies assessing catheter and evacuated tubes versus straight needle and evacuated tubes, and 1251 in 4 studies assessing catheter and evacuated tubes versus catheter and manual aspiration. A signifi cant risk of hemolysis was found in studies assessing catheter and evacuated tubes versus straight needle and evacuated tubes (random eff ect OR 3.4; 95% CI = 2.9-3.9 and random eff ect RR 1.07; 95% CI = 1.06-1.08), as well as in studies assessing catheter and evacuated tubes versus catheter and manual aspiration of blood (OR 3.7; 95% CI = 2.7-5.1 and RR 1.32; 95% CI = 1.24-1.40). Conclusions: Sample collection through intravenous catheters is associated with signifi cant higher risk of spurious hemolysis as compared with standard blood drawn by straight needle, and this risk is further amplifi ed when intravenous catheter are associated with primary evacuated blood tubes as compared with manual aspiration.