A systematic review and meta-analysis of microbial contamination of parenteral medication prepared in a clinical versus pharmacy environment

Purpose Preparation of parenteral medication in hospitals is a complex process with a risk of microbial contamination of the product, especially when inappropriately prepared. Contaminated parenteral medications can cause severe complications to patients and increase morbidity in hospitals. The aim of this literature review is to systematically evaluate the contamination rate of parenteral medications in hospitals prepared in a pharmacy environment and a clinical environment.Methods A literature search of PubMed and EMBASE from 2000 to 2018 was performed. Two different environments where preparation may be carried out were defined. Point estimates and 95% confidence intervals for contamination rates were calculated for each environment of medication preparation. The meta-analysis was performed using a random effects model.Results The contamination rates in the clinical environment (n = 13 studies) varied between 1.09 and 20.70%. In the pharmacy environment (n = 5), all contamination rates were 0.00% except for one study (0.66%). The point estimates (random effect model) for the overall contamination rate of doses prepared in the clinical environment was 7.47% (5.16-9.79%), and 0.08% for doses prepared in the pharmacy environment. The point estimates (random effect model) for the overall contamination rate of doses prepared by nursing/ medical staff was 7.85% (5.18-10.53%), and 0.08% for doses prepared by pharmacy staff.Conclusions Significantly higher contamination rates were found for the preparation of parenteral medication in the clinical environment compared to pharmacy environment. In accordance with recent guidance, the almost 100-fold higher changes of contamination when reconstitution is performed in the clinical environment should urge hospitals to review their reconstitution process and apply risk-reducing measures to improve patient safety of parenteral therapy.