[Influence of the donor's smoking on P50 of the banked blood].

Influence of the donor's smoking on the banked blood P50 was investigated. Twenty four male and 19 female donor's CPD blood were measured P50 immediately after donation with new P50 determing system. This system ( [P50-H] ) consists of a fully automatic blood gas analyser and Co-oxymeter and the oxygen equilibrium curve and P50 are mathematically determined with microcomputer. P50 of eleven male non-smokers was 24.8 +/- 1.9 mmHg at pH 6.98 +/- 0.06 and P50 of 16 male smokers was 22.9 +/- 1.2 mmHg at pH 6.97 +/- 0.08. On the otherhand, P50 of 13 female nonsmokers was 24.3 +/- 1.3 mmHg at pH 6.91 +/- 0.05 and P50 of 3 female smokers was 23.4 +/- 1.7 at pH 6.93 +/- 0.03. These data showed that P50 of smoker's blood was significantly low compared with non smoker's blood.