Early intravenous unfractionated heparin and outcome in acute lung injury and acute respiratory distress syndrome: a retrospective propensity matched cohort study.
BACKGROUND
Acute lung injury (ALI) is characterized by a pro-coagulant state. Heparin is an anticoagulant with anti-inflammatory properties. Unfractionated heparin has been found to be protective in experimental models of ALI. We hypothesized that an intravenous therapeutic dose of unfractionated heparin would favorably influence outcome of critically ill patients diagnosed with ALI.


METHODS
Patients admitted to the Intensive Care Unit (ICU) of a tertiary referral center in the Netherlands between November 2004 and October 2007 were screened. Patients who developed ALI (consensus definition) were included. In this cohort, the impact of heparin use on mortality was assessed by logistic regression analysis in a propensity matched case-control design.


RESULTS
Of 5,561 admitted patients, 2,138 patients had a length of stay > 48 hours, of whom 723 were diagnosed with ALI (34%), of whom 164 received intravenous heparin. In a propensity score adjusted logistic regression analysis, heparin use did not influence 28-day mortality (odds ratio 1.23 [confidence interval 95% 0.80-1.89], nor did it affect ICU length of stay.


CONCLUSIONS
Administration of therapeutic doses of intravenous unfractionated heparin was not associated with reduced mortality in critically ill patients diagnosed with ALI. Heparin treatment did not increase transfusion requirements. These results may help in the design of prospective trials evaluating the use of heparin as adjunctive treatment for ALI.
Department of Intensive Care Medicine, Academic Medical Center, University of Amsterdam, AZ, Amsterdam, The Netherlands. j.j.hofstra@amc.uva.nl
Jorrit J
JJ
Hofstra
Alexander P J
AP
Vlaar
David J
DJ
Prins
Gavin
G
Koh
Marcel
M
Levi
Marcus J
MJ
Schultz
Jan M
JM
Binnekade
Nicole P
NP
Juffermans
D055371:Acute Lung Injury / Q000188:drug therapy* / Q000401:mortality*; D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage / Q000627:therapeutic use*; D016022:Case-Control Studies; D015331:Cohort Studies; D016638:Critical Illness; D005260:Female; D006493:Heparin / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D007275:Injections, Intravenous; D007362:Intensive Care Units; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D012128:Respiratory Distress Syndrome / Q000188:drug therapy* / Q000401:mortality*; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
D000925:Anticoagulants; D006493:Heparin