Association between intraoperative blood transfusions and early postoperative delirium in older adults

Abstract

Objectives: To determine whether intraoperative blood transfusion, a known trigger and amplifier of inflammation, is an independent risk factor for early postoperative delirium (POD), an acute state of confusion with fluctuating consciousness and inattention after surgery, in older adults undergoing surgery.

Design: Secondary analysis using a database created for a prospective cognitive outcomes study.

Setting: University hospital.

Participants: Four hundred seventy-two individuals aged 65 and older undergoing major noncardiac surgery.

Measurements: Perioperative data were examined for association with POD on the first postoperative day. Multivariable logistic regression analysis was conducted to determine whether intraoperative blood transfusion independently predicts POD after adjusting for covariates known to be associated with onset of delirium and blood transfusions.

Results: One hundred thirty-seven individuals (29%) developed delirium on the first postoperative day. The multivariable logistic regression model identified age, sex, history of central nervous system disorder, preoperative cognitive dysfunction, and pain, as well as blood transfusions, as independent risk factors for POD. Intraoperative administration of more than 1,000 mL of red blood cells (RBCs) was the strongest predictor of POD on the first postoperative day (odds ratio = 3.68; 95% confidence interval = 1.32–10.94; P < .001).

Conclusion: Intraoperative blood transfusion of more than 1,000 mL of RBCs increases the risk of delirium on the first postoperative day in older adults undergoing noncardiac surgery.

Conflict of interest statement

Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper.

Figures

Figure 1

Results from the multivariable logistic model. Odds ratio estimates along with 95% confidence intervals are plotted for each covariate. We see blood transfusion of more than 1000 ml leads to the greatest risk of developing delirium on the first postoperative day. Abbreviations: TICS: Telephone Interview for Cognitive Status, VAS: Visual Analog Scale for Pain, ASA: American Society of Anesthesiologists