Abstract
Two young adults with impending gangrene due to persistent Raynaud's vasospasm were studied by sequential intra-arterial (IA) infusion of three vasodilatory drugs while arterial pressure and plethysmographic digital pulse volume were continuously monitored. The results of the IA infusion accurately predicted relief from vasospastic symptoms by oral drugs of the same class. This method may be useful in selecting the most effective vasodilator for patients with severe vasospasm.