THE EFFECT OF ARTERIALIZATION OF BLOOD BY HAND WARMING ON THE INTERPRETATION OF FOREARM METABOLIC STUDIES

Although sampling of arterialized blood is widely used as an alternati ve to arterial sampling in metabolic studies, the arterialization proc edures have been criticized because they may produce metabolic and hae modynamic effects that confound interpretation of results, especially in studies involving arteriovenous exchange of metabolites across the contralateral forearm. This study aimed to assess the effect of warmin g the hand for 10 or 20 min (a procedure which may be used to arterial ize superficial venous blood) on the blood flow to the skin and muscle of the whole of the contralateral forearm. Hand warming, produced by placing the hand in a box kept at 67 +/- 3-degrees-C for 10 min (stand ard errors of mean, SEM), produced no significant change in the blood flow of the whole forearm (4.14 +/- 0.28 versus 4.34 +/- 0.26 ml per 1 00 ml forearm min-1, measured with the hand circulation occluded), mus cle (1.9 +/- 0.12 versus 1.82 +/- 0.15 ml per 100 ml forearm min-1, me asured by Xe-133) or skin (5.2 +/- 4.0 versus 4.6 +/- 2.9 arbitrary un its, measured by photoplethysmography). After 20 min of hand warming, there was no significant change in the concentration of a variety of m etabolites in the deep venous blood draining the contralateral forearm . It is concluded that, unlike other 'arterialization' procedures, tha t used in this study had no important effect on the blood flow to the contralateral forearm or its distribution between muscular and non-mus cular tissues. Therefore, this procedure of arterialization can be emp loyed in arteriovenous studies that aim to assess the exchange of meta bolites between blood and forearm tissues.