Role of forearm vasoconstriction in the development of primary raynaud's disease

Abstract

Raynaud's Disease has been characterized as arteriolar constriction with a subsequent reduction of blood flow to the fingers. Few studies have investigated the regulation of blood flow into the hand in individuals with the disease. Therefore, the purpose of this study was to determine the relationship between Raynaud's disease and the forearm blood flow (FBF) response. Ten females (20.2±1.0 years), five control (CON) and five with the disease (RAY), completed two trials: a control visit and a cold‐induced visit. During the cold‐induced trial the left hand was placed in a cold bath (12°C) to induce Raynaud's symptoms. FBF was measured using venous occlusion plethysmography (Hokanson EC6). Reactive hyperemia was then determined by occluding the forearm for five minutes at 250 mmHg followed by peak FBF measurements. FBF and mean arterial pressure (MAP) were recorded pre, during the occlusion, and post trial. RAY exhibited the typical triphasic coloration changes indicating severe ischemia. Peak FBF after the occlusion in the cold trial was greater in RAY than CON indicating greater hyperemia (28.3 ± 4.8 vs. 26.2 ± 2.2 ml/100ml/min). MAP for CON was not different from RAY (87.37 ± 1.4 vs. 87.11 ± 2.37 mmHg). RAY demonstrated the typical ischemic response in the hand in response to a cold challenge in spite of a greater reactive hyperemia in the forearm suggesting a greater vasoconstriction response between the hand and forearm.