A number of workers have studied the altered vasomotor responses after sympathectomy. Usually consistently elevated basal flow was described after sympathectomy. However, reports have varied as to the changes in response to vasodilator and vasoconstrictor stimuli. Goetz found that flow to the toe did not respond to either constrictor or dilator stimuli after sympathectomy and that in some cases blood flow was decreased in response to vasodilator stimuli and increased in response to vasoconstrictor stimuli.
These authors could not correlate the changes in blood flow with changes in blood pressure. Ahmad reported a case of hyperhidrosis with homolateral sympathectomy in whom local
warming of the sympathectomized hand to 41 C caused vasoconstriction, while the nor-
mally innervated hand responded with vasodilation.
Pollock and co-workers observed what they called "defects in regulation of heat production, sweat and vasoconstriction" in patients with spinal cord lesions. They believed these defects to be due to interruption of "impulses from suprasegmental levels." In 1953 Armin, Grant, and co-workers demonstrated increased reactivity to vasoconstrictor stimuli in the denervated rabbit's ear and referred to a similar phenomenon in the human finger after sympathectomy.
The results, however, of studies on surgically sympathectomized patients are quite clearcut.
In none of the limbs studied after sympathectomy could an increase in blood flow be produced reflexly by warming; in the majority of instances the opposite response, a decrease in blood flow, was observed. The regularity with which these carefully sympathectomized limbs fail to respond to a vasodilator stimulus suggests that this procedure might be useful as a test for completeness of sympathectomy.
The vasomotor responses to the Gibbon-Landis procedure (reflex response to warming)
were studied in hemiplegic patients, subjects with "high transection" of the cord, and in
sympathectomized patients. The response in hemiplegic patients was vasodilator in nature
just as in the 3 control groups (young normal subjects, elderly subjects without demonstrable
vascular disease, and patients with arterio-sclerosis). One patient with documented tran-
section of the cord above T5 behaved like subjects after surgical sympathectomy. The differences in response in 3 other paraplegic patients may be due to differences in location
and extent of their cord lesions. Basal blood flow was higher in sympathectomized limbs
than in comparable controls. Of 11 sympathectomized limbs tested for vasodilatation in
response to the Gibbon-Landis procedure, 4 showed no response, while 7 responded with decrease in blood flow (vasoconstriction).
1957;15;518-524 Circulation Dorothy Andrews
WERTHEIMER, ARTHUR J. LEWIS, J. MURRAY STEELE and WALTER REDISCH, FRANCISCO T. TANGCO, LOTHAR
Vasomotor Responses in the Extremities of Subjects with Various Neurologic Lesions: I. Reflex Responses to Warming
