THE National Blood Data Resource Center, in its 1998 Nationwide Blood Collection and Utilization Survey, noted an alarming trend of decreasing numbers of blood donations and increasing numbers of blood transfusions. 1
A large percentage of allogeneic blood is administered in the operating room (OR), especially to cardiac surgery patients, 2,3
with 20% of transfusions thought to be inappropriate. 4
Blood shortages have been reported in many areas throughout the United States, necessitating delay of elective surgical procedures.
This article is accompanied by an Editorial View. Please see: Burmeister LF: Principles of successful sample surveys. Anesthesiology 2003; 99:1251–2.
The annual cost of blood transfusions in the United States has been estimated at $5–7 billion. 5
However, it is likely that the actual costs are much higher as a result of more widespread use of leukocyte-reduced components and the introduction of nucleic acid testing of donated blood. 6,7
There is great variability among institutions in transfusion practices, especially for cardiac surgery patients. 2,8
Educational outreach has improved transfusion practice in surgery, but there is still significant variability, and many institutions do not use laboratory tests to guide transfusion therapy. 8–10
Multiple consensus conferences and specialty society task forces have been convened in the United States to develop recommendations for the transfusion of blood components. These organizations include the National Institutes of Health, 11–13
the American College of Obstetricians and Gynecologists, 14
the American Association of Blood Banks, 15
the American College of Physicians, 16
the College of American Pathologists, 17,18
and the American Society of Anesthesiologists (ASA). 19
Educational programs can improve transfusion practices, 20
but many institutions may not provide any educational programs or transfusion guidelines.
The most recent survey of anesthesiologists’ transfusion practice was performed in 1981 and published in 1987. 21
To assess current transfusion practices, identify changes in practice that have occurred since the 1981 survey, and determine the need for future educational endeavors, the ASA Committee on Transfusion Medicine conducted a survey of active ASA members in 2002. We also sought to determine whether members were familiar with the ASA Practice Guidelines for Blood Component Therapy (hereafter referred to as the ASA Guidelines) published in 1996 19
and whether they seemed to be following them.
Materials and Methods
The majority of the survey questions were identical to those on the previous survey so that the responses could be compared. Some questions were modified to incorporate responses based on the ASA Guidelines. Questions regarding the frequency of administering transfusions, the criteria for reinfusing predonated autologous blood, the use of whole blood, and intraoperative performance of hemoglobin determinations and coagulation tests were added. Demographic data regarding the member's practice location, years in practice, type of practice, and certification were included.
After institutional review board approval, the survey was mailed to 2,500 randomly selected active members of the ASA, representing approximately 10% of the active membership. A power analysis before performing the survey revealed that 750 respondents would result in an approximate precision for point estimates of ± 3.7% based on the half-length of a 95% confidence interval assuming a point estimate of 50%. We assumed a 30% response rate. Therefore, 2,500 surveys at a 30% response rate would result in 750 survey responses. The randomization was performed with use of a computer. Resident, affiliate, honorary, life, and retired members were excluded. The identity of respondents remained anonymous.
The number of respondents (i.e., the denominator used to calculate the percentage response) dictates the precision of the corresponding point estimate. With 862 responses, the approximate precision for point estimates is ± 3.4% based on the half-length of a 95% co