Autologous blood donation: hemodynamics in a high-risk patient population

Transfusion practices have changed dramatically in recent years as a result of the acquired immune deficiency syndrome crisis. The use of preoperative donation of autologous blood units has gained popularity. Healthy individuals tolerate phlebotomy well, experiencing a 2- to 5-percent incidence of vasovagal reactions. However, no systematic study of hemodynamic function during phlebotomy exists for patients who have major cardiovascular or multiple organ disease (high-risk patients). The following protocol examines blood pressure, heart rate, cardiac output, lead II electrocardiogram, and pulse oximetry in 123 patients donating a total of 224 units of blood in a new high-risk autologous blood donation program that was conducted in a postanesthesia care unit over the past 18 months. Changes in hemodynamic variables during phlebotomy were consistent with mild volume depletion; the changes did not result in overall differences in the courses of the groups. Significant numbers of patients exhibited systolic or diastolic hypotension, dysrhythmias, syncope, and tachycardia. Because tolerance for hypotension (vasovagal reactions) is decreased in patients with coronary artery disease, appropriate monitoring may be warranted to maximize the safety of elective phlebotomy. Further study is required to stratify risks and to determine which hemodynamic variables are predictive of adverse events.