Amongst the 7,206 blood donors who reported for donating blood donation centre, 1,081 (15%) donors were deferred for various reasons, out of which 400 (37%) deferrals [253 males (63.3%) and 147 females (36.7%)] were due to low Hb value on analysis of donors capillary blood sample with the CuSO4 specific gravity method.
Hb value of donors deferred for low Hb are show in Table 1.
Donor’s age ranged from 21 years to 54 years.
The deferral rate was much higher in female donors (54%) compared to male donors (5%).
Amongst the total donors deferred during this period, 37% deferrals were due to low Hb levels.
116 (29%) of the donors deferred by CuSO4 method had their Hb level >12.5 g/dl on analysis with the Coulter counter.
The Hb level of 131 (32.8%) of deferred donors was between 12 and 12.4 gm/dl by the Coulter counter method. The hematocrit value of these donors was between 36% and 40% .
The sensitivity and specificity, PPV and NPV of the other three hemoglobin screening methods with reference to the Coulter counter using capillary and venous blood samples are shown in table 2.The concordance correlation coefficient between Hemocue and the reference method was 0.74 (capillary samples) and 0.89 (venous samples) whereas the corresponding values obtained for Cyanmeth Hb method were 0.78 and 0.91, respectively.
The mean Hb value as obtained by the reference method was higher with capillary samples in comparison to the venous samples (Mean difference=0.2g/dl)