RESUMO
BACKGROUND: Usually, a predonation hemoglobin (Hb) measurement must precede blood donation. Hb values of a donor's previous donation might be used for selecting a subgroup in which predonation Hb measurements are unnecessary. STUDY DESIGN AND METHODS: Only donors with historical Hb values below 129 or 139 g per L for female and male donors, respectively, underwent venous Hb measurement before phlebotomy with an automated hematology analyzer. All other donor phlebotomies were collected without initial Hb testing. Hb values from diversion samples from 81,913 consecutive donors between May 2003 and November 2005 were subsequently analyzed as representing their present values. Donors were grouped according to interdonation intervals of less than 6, 6 to 11, 12 to 23, and 24 months or more. RESULTS: The arithmetic mean deviation between historical and present Hb values was between -0.3 and +1.8 g per L for each group (mean deviation, 5.2-6.7 g/L). Not testing selected donors spared 77.7 percent from a prephlebotomy Hb measurement and showed a specificity of 29 percent. Sensitivities for detection of donors below Hb limits (between 56% and 67% for the different subgroups) and donors with Hb values below 110 g per L (82%-88%) were at least comparable to capillary Hb screening. A total of 4.8 percent of donors were phlebotomized with values below 125 and 135 g per L, whereas only 0.016 percent of donors were bled despite Hb levels below 110 g per L. CONCLUSION: Selecting donors for a current Hb measurement based upon their last whole-blood predonation Hb value is a useful method, even after prolonged interdonation intervals.
