phenylephrine response/sensitivity measurement vasoconstrictor-induced blood vessel contractile force expressed as percent of force at baseline phenylephrine-induced blood vessel contractile force expressed as percent of force at baseline 2014-06-09T17:21:51Z A calculated measurement in which the difference between the contractile force of a blood vessel in response to a specified dosage of phenylephrine and the baseline contractile force exerted by that vessel in the absence of any external stimuli, is divided by the baseline contractile force measurement and the result expressed as a percentage. Phenylephrine is an adrenergic drug that is a powerful vasoconstrictor. JSmith phenylephrine-induced blood vessel constriction expressed as percent of force at baseline