Alcohol Distribution in the Vascular System: Concentration of Orally Administered Alcohol in Blood from Various Points in the Vascular System, and in Rebreathed Air, During Absorption

Abstract

In 11 experiments, 8 men ingested 1.03 g of alcohol/kg of body weight during 30 minutes. Immediately afterward and at specified intervals later, determinations were made of the alcohol level of blood from certain points in the vascular system and of rebreathed air. Cubital vein blood and rebreathed air were analyzed in all experiments. The other blood sources used in some of the experiments were fingertip, radial artery, dorsal hand vein, dorsal foot vein, and tip of the large toe. The cubital vein blood alcohol level lagged significantly behind the level of fingertip capillary blood for 1/2 hour after the end of drinking, the average cubital vein: fingertip blood alcohol ratios of five subjects being 0.76 immediately after the end of drinking, 0.83 at 15 minutes and 0.93 at 30 minutes. The alcohol level of cubital vein blood lagged even more behind the level of arterial blood during absorption. Here the average venous: arterial blood alcohol ratios were 0.60 immediately after the end of drinking, 0.76 at 15 minutes and 0.85 at 30 minutes. In one subject it was 0.84 at 45 minutes. The rebreathed air values (mg alcohol/2.1 liters X 100) correlated well with the arterial blood alcohol levels, the average deviation of the rebreathed air values being -6% in 9 pairs of samples. During the period of absorption the rebreathed air values somewhat exceeded the fingertip capillary blood alcohol levels and greatly exceeded the venous blood alcohol levels. Tests made at 7 intervals during a 2-hour period following the end of drinking showed no significant difference in the alcohol levels of cubital vein blood and blood from the dorsal vein of the hand. At 15 minutes after the end of drinking, the alcohol levels of dorsal foot vein blood and capillary blood from the large toe were far below those of cubital vein blood. The peak in the alcohol level of arterial or fingertip capillary blood was reached considerably sooner and was usually higher than the alcohol peak of cubital vein blood. In employing analysis of other body materials for predicting the alcohol level of arterial blood and brain during absorption, it appears that the choice of material, in descending order of reliability, is rebreathed air or alveolar air, finger- tip blood, blood from cubital vein or dorsal hand vein, and blood from dorsal foot vein or large toe.