Transfusion practice and blood stream infections in critically ill patients

Study objective: To examine the relationship between packed RBC (pRBC) transfusion and the development of ICU-acquired bloodstream infections (BSIs) Design: Secondary analysis of a large, prospective, observational study of transfusion practice in critically ill patients. Setting: A total of 284 adult ICUs in the United States. Patients: Critically ill adults who lacked BSIs both at ICU admission and 48 h after ICU admission. Interventions: None. Measurements and results: BSIs were prospectively tracked in this study, and diagnosis of a new BSI represented the primary end point. Transfusions administered in the ICU prior to development of a BSI were also prospectively recorded. Of 4,892 patients enrolled in this investigation, 3,502 patients lacked BSIs both at ICU admission and 48 h later. Among these individuals, 117 patients (3.3%) had an ICU-acquired BSI. In multivariate analysis adjusting for severity of illness, primary diagnosis, use of mechanical ventilation, placement of central venous catheters, and ICU length of stay, three variables were independently associated with diagnosis of a new BSI: baseline treatment with cephalosporins (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.26 to 2.68), higher sequential organ failure assessment score measured on ICU days 3 to 4 (OR, 1.11; 95% CI, 1.06 to 1.16), and pRBC transfusion (OR, 2.23; 95% CI, 1.43 to 3.52). The relationship between pRBC transfusion and BSI was evident with both small transfusion volumes (OR with 1- to 2-U pRBC transfusion, 1.89; 95% CI, 1.10 to 3.23) and larger transfusion volumes (OR with > 4-U pRBC transfusion, 2.63; 95% CI, 1.52 to 4.53). Conclusions: pRBC transfusion is associated with subsequent ICU-acquired BSI. Avoiding unnecessary transfusions may decrease the incidence of BSIs.