Recovery of hemoglobin mass after blood donation.

BACKGROUND: Blood donation plays an important role in every health care system. Measurement of hemoglobin (Hb) concentration or hematocrit to assess hematologic recovery after donation may not adequately reflect the true amount of blood as they are affected by plasma volume fluctuations. Instead, total Hb mass (tHb) is the variable of choice and can be determined in routine clinical practice. Therefore, the purpose was to investigate the recovery of tHb after standard blood donation. STUDY DESIGN AND METHODS: The optimized CO rebreathing method was used for evaluation of tHb before and after 1-unit (erythrocyte concentrate) standard blood donation in 29 male volunteers (30 +/- 10 years, 181 +/- 7 cm, 76.6 +/- 11.2 kg). Subsequently, tHb measurements were performed in regular intervals until one of two termination criteria was met. RESULTS: After donation of approximately 550 mL of whole blood, the lost amount of tHb of 75 +/- 15 g (8.8 +/- 1.9%) was recovered after a mean of 36 +/- 11 days (range, 20-59 days). CONCLUSIONS: The results of this study confirm the minimal, recommended donation intervals (56 days for men) as adequate when, for the first time, judged upon by tHb as a direct marker of hematologic recovery.