title: Is platelet transfusion associated with hospital-acquired infections in critically ill patients?
abstract: Platelets are commonly transfused to critically ill patients. Reports suggest an association between platelet transfusion and infection. However, there is no large study to have determined whether platelet transfusion in critically ill patients is associated with hospital-acquired infection.
  
  
  
  We conducted a multi-centre study using prospectively maintained databases of two large academic intensive care units (ICUs) in Australia. Characteristics of patients who received platelets in ICUs between 2008 and 2014 were compared to those of patients who did not receive platelets. Association between platelet administration and infection (bacteraemia and/or bacteriuria) was modelled using multiple logistic regression and Cox regression, with blood components as time-varying covariates. A propensity covariate adjustment was also performed to verify results.
  
  
  
  Of the 18,965 patients included, 2250 (11.9%) received platelets in ICU with a median number of 1 platelet unit (IQR 1-3) administered. Patients who received platelets were more severely ill at ICU admission (mean Acute Physiology and Chronic Health Evaluation III score 65 (SD 29) vs 52 (SD 25), p < 0.01) and had more comorbidities (31% vs 19%, p < 0.01) than patients without platelet transfusion. Invasive mechanical ventilation (87% vs 57%, p < 0.01) and renal replacement therapy (20% vs 4%, p < 0.01) were more frequently administered in patients receiving platelets than in patients without platelets. On univariate analysis, platelet transfusion was associated with hospital-acquired infection in the ICU (7.7% vs 1.4%, p < 0.01). After adjusting for confounders, including other blood components administered, patient severity, centre, year, and diagnosis category, platelet transfusions were independently associated with infection (adjusted OR 2.56 95% CI 1.98-3.31, p < 0.001). This association was also found in survival analysis with blood components as time-varying covariates (adjusted HR 1.85, 95% CI 1.41-2.41, p < 0.001) and when only bacteraemia was considered (adjusted OR 3.30, 95% CI 2.30-4.74, p <0.001). Platelet transfusions remained associated with infection after propensity covariate adjustment.
  
  
  
  After adjustment for confounders, including patient severity and other blood components, platelet transfusion was independently associated with ICU-acquired infection. Further research aiming to better understand this association and to prevent this complication is warranted.
authors.affiliation: Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia. Cecile.aubron@chu-brest.fr.|Réanimation Médicale, Centre Hospitalier et Universitaire de Brest site La Cavale Blanche - Université de Bretagne Occidentale, Bvd Tanguy Prigent, 29609, Brest Cedex, France. Cecile.aubron@chu-brest.fr.
authors.forename: Cécile
authors.initials: C
authors.lastname: Aubron
authors.affiliation: Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.|Joint Health Command, Australian Defence Force, Canberra, Australian Capital Territory, 2160, Australia.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Flint
authors.affiliation: Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Bailey
authors.affiliation: Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.|Intensive Care Unit, The Alfred Hospital, Melbourne, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Pilcher
authors.affiliation: Department of Infectious Disease, The Alfred Hospital, Melbourne, Australia.|Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Allen C
authors.initials: AC
authors.lastname: Cheng
authors.affiliation: Transfusion Service, Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.
authors.forename: Colin
authors.initials: C
authors.lastname: Hegarty
authors.affiliation: Transfusion Service, Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria, 3084, Australia.
authors.forename: Antony
authors.initials: A
authors.lastname: Martinelli
authors.affiliation: Burns Trauma and Critical Care Research Centre, University of Queensland, Herston, Queensland, 4029, Australia.|Joint Health Command, Australian Defence Force, Canberra, Australian Capital Territory, 2160, Australia.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Reade
authors.affiliation: Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.|Intensive Care Unit, Austin Hospital, Melbourne, Australia.
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.affiliation: Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.|Transfusion Research Unit, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.
authors.forename: Zoe
authors.initials: Z
authors.lastname: McQuilten
mesh_terms: D000368:Aged; D001315:Australia; D016470:Bacteremia / Q000453:epidemiology / Q000209:etiology; D001437:Bacteriuria / Q000453:epidemiology / Q000209:etiology; D016638:Critical Illness / Q000453:epidemiology / Q000628:therapy*; D005260:Female; D006801:Humans; D007049:Iatrogenic Disease / Q000453:epidemiology*; D007362:Intensive Care Units / Q000706:statistics & numerical data; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017713:Platelet Transfusion / Q000592:standards* / Q000706:statistics & numerical data; D011446:Prospective Studies; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: Bacteraemia; Critically ill patients; Hospital-acquired infection; Platelet transfusion