The objective diagnosis of vibration-induced vascular injury.

For 44 patients with vibration-induced white finger and a reference group of 25 healthy men, finger systolic blood pressure (FSBP) before and after local cooling, skin temperature, and rewarming rates were determined before and after vasodilation (body warming and alcohol). An estimation of the proportions of vasopasm and organic changes was possible, and cutaneous changes could be separated from changes in the main digital vessels. The arm blood pressure was higher for the patients and the fingertip temperatures were lower, but both normalized after vasodilation. The FSBP values were equal in the two groups before local cooling. Afterward the patients had lower FSBP values which remained unchanged after the postvasodilatation cooling. Ten patients, all smokers, reacted with complete arterial closure after local cooling. When this group was separated from the other smoking patients, there was no significant difference between the smoking and nonsmoking patients, and the FSBP differences between the patients and referents was almost eliminated. It was concluded that, in vibration-exposed patients, injuries to skin circulation seem to be more frequent than injuries to the main digital vessels, except for some smokers, who have severe vasopasm combined with organic changes.