Flow ratios to express results obtained with the human in vivo 'perfused forearm technique'.
OBJECTIVE
To determine the accuracy of forearm blood flow (FBF) ratio (flow in infused arm/flow in control arm) to detect unilateral increases in forearm blood flow.


METHODS
In nine healthy male volunteers, we measured the effect of infusion of saline into the brachial artery at a rate of 2 ml/100 ml forearm min-1 on FBF ratio during control, mental arithmetic (MAR) and lower body negative pressure (LBNP) at -40 mmHg.


RESULTS
Saline infusion increased FBF ratio from baseline by 115.9+/-17.4, 82.0+/-19.0 and 159.6+/-53.3% for control, MAR and LBNP, respectively (P<0.05 for MAR vs control).


CONCLUSIONS
FBF ratio may underestimate unilateral increases in forearm blood flow during simultaneous mental arousal.
Department of Medicine, Division of General Internal Medicine University Hospital Nijmegen, Nijmegen, The Netherlands.
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GA
Rongen
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Lambrou
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Smits
D000328:Adult; D001916:Brachial Artery; D005542:Forearm / Q000098:blood supply*; D006801:Humans; D007261:Infusions, Intra-Arterial; D008150:Lower Body Negative Pressure; D008297:Male; D010477:Perfusion; D012039:Regional Blood Flow; D013315:Stress, Psychological / Q000503:physiopathology