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HANDBOOK OF PHYSIOLOGY ^ CIRCULATION II 



at will by cooling this finger alone, or even by cooling 

 a short stretch of it; for the digital arteries in their 

 whole length possess this liability to closure. The state 

 of closure once established can be released by warm- 

 ins; the hands; and this can also be affected in the 

 arteries of separate fingers, or even in the arteries 

 at the base of a finger, by warming the finger or its 

 base separately. 



"It has been indicated already that, when a normal 

 subject is exposed to cold, arteries like the digital 

 narrow under two influences; they constrict as a 

 direct reaction to cold, and because vasomotor 

 nervous tone increases. These same two factors 

 operate in the fingers of the cases we are discussing, 

 under conditions of general cooling. But, because 

 in these cases there is an abnormality, the vessels 

 do what they will not do in normal subjects, they 

 close to obliteration. The evidence proves that the 

 abnormal element is local, and not, as formerly 

 thought, in the response of the nervous system. Thus, 

 if vasomotor tone is deliberately reduced by warming 

 the subject's body, immersion of the hand of a sus- 

 ceptible subject in cold water will still induce the 

 attack; but if the hand is kept warm, an increase of 

 vasomotor tone, induced by cooling the body, will 

 not provoke the attack. Again, if the circulation to 

 the fingers of such a patient has become arrested by 

 general exposure to cold, local destruction of vaso- 

 motor tone by nerve anaesthetisation does not bring 

 instant release of blood-flow, which would happen 

 inevitably if vasomotor tone were alone responsible: 

 it brings delayed release, or the release fails. Likewise, 

 as experience has shown, destruction of the sympa- 

 thetic nerve supply to the limb by surgical inter- 

 vention does not cure the malady: for it frequently 

 happens that patients so treated continue subse- 

 quently to display attacks on exposure to cold; and 

 after sympathectomy the local susceptibility can 

 always be demonstrated by special tests in sensitive 

 cases and this is so even when the sympathectomy is 

 preganglionic. The local abnormality is the reason 

 for this, for it remains unchanged. 



"Although the facts show that the fault is not in 

 the nervous system, that is not to say that the nervous 

 system plays no part in the attacks. If under the 

 direct influence of cold the arterial channels of a 

 hand become unusually narrowed, but not quite 

 obliterated, then subsequent cooling of the trunk, 

 or an emotional disturbance, or a painful stimulus, 

 by normally increasing vasomotor tone, will cause 

 the vessels to close completely and thus determine 

 an attack. It is this kind of event that has been 



misinterpreted in the past, and has given support to 

 the wrong idea that the vasomotor nervous system is 

 primarily at fault. Further it will be apparent that 

 anything reducing or abolishing vasomotor tone will 

 on occasion bring an attack to an end, and continuing 

 as an influence will tend to prevent the recurrence of 

 attacks. This is the basis upon which the modern 

 treatment by sympathectomy rests; its successful 

 results are due, not to interference with the passage 

 of abnormal nervous impulses, but to the destruction 

 of normal vasomotor tone." 



Lewis emphasized that if one finger of a subject 

 with the disease is immersed in cold water, the attack 

 is frequently confined to this finger. He felt that such 

 a sharply localized response could not be explained 

 on the basis of a nervous reflex. 



More recent publications (8, 52, 62) presented evi- 

 dence in support of Lewis' theory of a "local fault" in 

 the blood vessels. By plethysmography and thermom- 

 etry it was demonstrated that patients with Ray- 

 naud's phenomenon have an increased sensitivity 

 to cold as compared to normal subjects and that this 

 state persists even after successful sympathetic dener- 

 vation. These studies were not meant to imply that 

 sympathectomy is of no benefit to the patients. When 

 the patient's peripheral vessels are maximally dilated 

 by the procedure and heated by the warm blood 

 flowing through them, a decrease of the vessel tem- 

 perature to the critical level is not as easily produced. 

 Further, cooling of the vessels by vasoconstriction 

 can no longer be induced reflexly from emotional 

 disturbances, pain, or body chilling. 



Whether or not ether vessels besides the digital 

 arteries participate actively in the Raynaud's reac- 

 tion has been debated. Naide & Sayen (66) con- 

 sidered that arterial spasm alone cannot explain the 

 entire clinical picture. They presented evidence, 

 though not conclusive, that spasm of the digital veins, 

 as well as the digital arteries, exists. It was based 

 largely on observations that in some patients with 

 Raynaud's disease the digits began to appear puffed 

 and cyanotic before blanching occurred. The authors 

 considered this to indicate venoconstriction prior 

 to arterial constriction. 



Capillarioscopy has been of value in detecting 

 vascular change in the various reactions of Raynaud's 

 disease (3, 18). During the stage of pallor, no blood 

 enters the capillaries of the involved digits. During 

 the stage of cyanosis, more than the usual number of 

 of capillaries are engorged with blood, and many 

 are greatly dilated. They are filled with stagnant 

 blood. Venules may also be dilated during this stage, 



