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Clinical factors associated with an increased risk of perioperative blood transfusion in nonanemic patients undergoing total hip arthroplasty.

BACKGROUND
The aim of this study was to identify clinical factors associated with an increased need for perioperative blood transfusion in nonanemic patients undergoing total hip arthroplasty.


METHODS
We evaluated eighty-five consecutive nonanemic patients who underwent elective, unilateral, cementless, primary total hip arthroplasty and met our inclusion criteria. We attempted to determine whether clinical parameters influencing perioperative blood loss, such as age, gender, hypertension, and body mass index, were also associated with the need for perioperative blood transfusion.


RESULTS
Perioperative blood transfusion was required in twenty-four (28%) of the eighty-five nonanemic patients. When considered alone, age, gender, hypertension, and body mass index were not significantly associated with an increased risk of perioperative blood transfusion, on the basis of the numbers available. In contrast, there was a significantly increased risk of blood transfusion when two or more of these clinical parameters were present (p = 0.02).


CONCLUSIONS
Our findings indicate that clinical variables such as age, gender, hypertension, and body mass index may have a synergistic effect on the risk of transfusion in patients undergoing elective total hip arthroplasty. The simultaneous analysis of these parameters might help to stratify patients with different risks for transfusion and may increase the efficiency and reduce the cost of blood-ordering practices associated with total hip arthroplasty.


LEVEL OF EVIDENCE
Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.