A pilot study of the relationship between Doppler-estimated carotid and brachial artery flow and cardiac index

Abstract

Summary We measured carotid and brachial artery blood flow by Doppler ultrasound in 11 human volunteers, and related these to cardiac index and to each other. The median (IQR [range]) carotid arterial blood flow was 0.334 (0.223-0.381 [0.052-0.563]) l.min-1 on the right and 0.315 (0.223-0.369 [0.061-0.690]) l.min-1 on the left. The brachial arterial blood flow was 0.049 (0.033-0.062 [0.015-0.204]) l.min-1 on the right and 0.039 (0.027-0.054 [0.011-0.116]) on the left. Cardiac index was 3.2 (2.8-3.5 [1.9-5.4]) l.min-1.m-2. There was a moderate to good correlation between right-and left-sided flows (brachial: ρ = 0.45; carotid: ρ = 0.567). Brachial and carotid flow had no or a negative correla..