Digital Pressure-Flow Relationships in Subjects with Raynaud's Phenomenon

Abstract

In order to determine whether subjects with Raynaud's phenomenon have altered digital hemodynamics in the warm basal condition, we characterized the digital pressure-flow relationships in seven subjects with Raynaud's phenome non and compared the results with age and sex matched control subjects. Digital pressure-flow relationships were measured by the use of a plethysmographic technique during passive elevation of the arm. Normal subjects demonstrated a positive finger systolic pressure at zero flow (48.3 mmHg), indicative of a criti cal closing pressure, however, the closing pressure was significantly higher in the subjects who had a history of Raynaud's phenomenon (64.7 mmHg, p < .001). In contrast, there was no significant difference found in the conduc tance measured as the slope of the pressure-flow relationship. Subjects with Raynaud's phenomenon demonstrated a correlation between finger systolic pressure and critical closing pressure suggesting that these subjects may regu late arterial pressure through a critical closing pressure mechanism.