LABORATORY IMMUNOLOGY - IMMUNE MONITORING AND MOLECULAR DIAGNOSIS

A. Cochran¹, M.J. Nowicki², D. Bryant¹, C. Chinchilla-reyes², M. Stadtler¹, T. Mone^1
1, OneLegacy, Los Angeles/CA/UNITED STATES OF AMERICA, ², Mendez National Institute of Transplantation, Los Angeles/CA/UNITED STATES OF AMERICA

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Background As the transplanted organ and tissue are commonly derived from donors who died traumatic deaths the possibility of pre-consent blood loss and post-consent solutions infusion is likely. It was suggested that the extensive blood loss prior to sampling, and not transfusion with colloids/crystalloid, creates hemodilution sufficient to affect screening (Cell and Tissue Banking,1, 121-127, 2000). Current formulas and algorithm (FDA) do not distinguish between hemodilution volumes with blood/blood products and other fluids. The extent of hemodilution and the effect on serologies and NAT is poorly understood and urgently needed as more ECDs are recruited. Aim To re-evaluate currently use hemodilution algorithm 48 hrs prior to consent/blood draw. Method To evaluate 48hrs pre-blood draw hemodilution we randomly selected 30 donors (17 non-trauma and 13 trauma-related deaths) from 382 donors with organs procured by our OPO in 2009. Fifteen donors were ECD and 15 were SCD. We performed detailed chart abstraction, collecting the following information: weight (WT), sex, cause of death, age, blood volume (BV), plasma volume (PV), volume of blood/blood products, volume of infused colloids and crystalloids. To calculate blood and plasma volumes we used FDA algorithm based upon PV=WT/0.025 and BV=WT/0.015. All donors were HIV, HCV and HBsAg negative. Results The median calculated blood volume was 5.4l (3.33l-10.53l ), plasma volume 3.09l (2.00l-6.33). Only 2/30 donors (trauma-related deaths) received blood transfusion with pack red cells prior to consent. The most common treatment was infusion with crystalloids (29/30) followed by infusion with colloids (4/30). The average hemodilution for all fluids was 7.1+ 7.4% (range 0-28%). However, mean hemodilution using blood product only was much lower: 0.4+1.7 Conclusions Based upon our data, pre-blood draw treatment with non-blood fluids is common among organ donor. However, only few donors are transfused. Currently used FDA formula may not be suitable in cases of obese donors and seems to overestimate hemodilution by not taking into account different equalization rates of blood (slow equalization), colloids and crystalloids (fast equalization). We found no evidence of hemodilution exceeding 50%, which is currently believed to be the safe threshold for serological test.

Disclosure: All authors have declared no conflicts of interest.