PERIPHERAL VASCULAR DISEASES 



I 24I 



these experiments tend to lend support in part to 

 the concept of reflex arterial constriction, the latter 

 observation regarding venous dilatation is not in 

 accordance with the concept of venous or venular 

 constriction. This factor in thrombophlebitis had 

 been difficult to accept in the light of the intense 

 congestion and obvious distention of the small veins 



(3)- 



The theory that associated vasospasm in throm- 

 bophlebitis is a frequent and important pathophysio- 

 logic factor is intriguing but more definitive ex- 

 perimental work is required for confirmation and 

 general acceptance in clinical medicine. 



Vasodilative Syndromes 



Vasodilatation as an important vascular response 

 is seen in a number of physiologic states such as 

 thermoregulation, tissue inflammatory response, reac- 

 tive hyperemia, early stages of causalgia, and the like, 

 but the cardinal condition which concerns us here 

 is erythromelalgia. 



erythromelalgia (erythermalgia). Early con- 

 tributors to the literature of this disease state were 

 Graves in 1834 (63), Mitchell in 1872 (63), Cassirer 

 in 1 91 2 (12), and May & Hillemand in 1924 (57). 

 Significant contributions after that time include the 

 work of Brown in 1932 (7), Lewis in 1933 (45), and 

 Smith & Allen in 1938 (91 ). Since then, little definitive 

 work has been done and published on erythro- 

 melalgia. 



Erythromelalgia is a vasodilative syndrome char- 

 acterized by episodes of erythema, increased heat 

 and pain involving the hands and especially the feet. 

 It has been placed into primary and secondary 

 categories. "Primary erythromelalgia" occurs in 

 otherwise healthy individuals who manifest no de- 

 tectable evidence of organic disease of the nervous 

 or vascular systems. Analogous to Raynaud's phe- 

 nomenon, "secondary erythromelalgia" occurs in 

 association with or as a secondary symptom complex 

 of some other primary disease, such as hypertension, 

 occlusive organic vascular disease or polycythemia. 

 Gout, organic neurologic disease, frostbite, immersion 

 foot, trenchfoot, infectious diseases, and heavy metal 

 poisoning are also incriminated. 



The mechanism of erythromelalgia is unknown and 

 the pathology has not been clarified. Symptoms 

 usually start in middle age or later and may affect 

 either sex. It is apparently rare in the Negro (74). 



The clinical picture may be quite dramatic. The main 

 complaint is usually burning pain in the extremities, 

 especially in the feet and frequently in the hands. 

 Occasionally the disturbance may extend as high as 

 the knees or thighs. The patient usually complains 

 that the distress affects primarily the balls of the feet 

 and tips of the toes or corresponding parts of the hand. 

 It may last from a few minutes to several hours. 

 Usually the patient relates aggravation by dependency 

 of the part, by warmth, accentuation during summer 

 months, relief by cold and elevation of the part, and 

 lessened symptoms during winter. Attacks may be 

 precipitated by exercise which increases the warmth 

 of the skin. For unknown reasons, dry heat seems to 

 be more provocative than wet heat at the same tem- 

 perature. The discomfort may start as a "pricking" 

 paresthetic feeling then progress to a more typical 

 severe burning pain. During the subsidence of the 

 episode the pricking stage may again be noticed. In 

 the primary disease, neurological examination is 

 negative and examination of the peripheral vascula- 

 ture shows no evidence of occlusive arterial disease. 

 Trophic changes, ulceration, and gangrene are quite 

 rare, though some swelling may be evident in the 

 involved extremities. 



What is known of the pathophysiology of this 

 syndrome is interesting. The most important part of 

 this syndrome is its intimate relationship with the 

 temperature of the skin. Lewis (45) has designated a 

 "critical point" in skin temperature at which this 

 syndrome may be produced in susceptible individuals. 

 It usually is around 32 C (range, 31 to 36 C). With 

 temperatures higher than this critical point, the 

 distress continues and with temperatures lower than 

 this point the distress disappears (3, 91). The tem- 

 perature at which the syndrome may be produced 

 varies with different patients and also to some degree 

 in different parts of the extremity in the same person, 

 but in the same person the range is usually within 

 ±1 C. 



Vasodilation per se seems to be an important 

 vascular factor in the production of the erythro- 

 melalgic crises. Increased blood flow is only an indirect 

 accompaniment. Thus, the syndrome may be pro- 

 duced by warming the extremity to the critical level, 

 and the symptoms continued even though blood 

 flow is arrested by an inflated constricting blood 

 pressure cuff. This is so, provided the skin tempera- 

 ture is maintained at levels equal to or greater than 

 the critical point. 



As Lewis has pointed out, however, although 



