The association of perioperative red blood cell transfusions and decreased long-term survival after cardiac surgery.
BACKGROUND
Exposure to red blood cell (RBC) transfusions has been associated with increased mortality after cardiac surgery. We examined long-term survival for cardiac surgical patients who received one or two RBC units during index hospitalization.


METHODS
Nine thousand seventy-nine consecutive patients undergoing coronary artery bypass graft, valve, or coronary artery bypass graft/valve surgery at eight centers in northern New England during 2001-2004 were examined after exclusions. A probabilistic match between the regional registry and the Social Security Administration's Death Master File determined mortality through June 30, 2006. Cox Proportional Hazard and propensity methods were used to calculate adjusted hazard ratios.


RESULTS
Thirty-six percent of patients (n = 3254) were exposed to one or two RBC units. Forty-three percent of RBCs were given intraoperatively, 56% in the postoperative period and 1% were preoperative. Patients transfused were more likely to be anemic, older, smaller, female and with more comorbid illness. Survival was significantly decreased for all patients exposed to 1 or 2 U of RBCs during hospitalization for cardiac surgery compared with those who received none (P < 0.001). After adjustment for patient and disease characteristics, patients exposed to 1 or 2 U of RBCs had a 16% higher long-term mortality risk (adjusted hazard ratios = 1.16, 95% CI: 1.01-1.34, P = 0.035).


CONCLUSIONS
Exposure to 1 or 2 U of RBCs was associated with a 16% increased hazard of decreased survival after cardiac surgery.
Surgenor
Stephen D
SD
Dartmouth-Hitchcock Medical Center, Department of surgery, 1 Medical Center Drive Lebanon, NH 03756, USA. Stephen.D.Surgenor@Hitchcock
Kramer
Robert S
RS
Olmstead
Elaine M
EM
Ross
Cathy S
CS
Sellke
Frank W
FW
Likosky
Donald S
DS
Marrin
Charles A S
CA
Helm
Robert E
RE
Leavitt
Bruce J
BJ
Morton
Jeremy R
JR
Charlesworth
David C
DC
Clough
Robert A
RA
Hernandez
Felix
F
Frumiento
Carmine
C
Benak
Arnold
A
DioData
Christian
C
O'Connor
Gerald T
GT
D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000628:therapy; D006348:Cardiac Surgical Procedures / Q000401:mortality*; D015331:Cohort Studies; D001026:Coronary Artery Bypass; D017707:Erythrocyte Transfusion / Q000009:adverse effects*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D019990:Perioperative Care; D016016:Proportional Hazards Models; D011446:Prospective Studies; D013534:Survival; D016896:Treatment Outcome