- Raynaud phenomenon (RP), a vasospastic reaction to cold temperatures or emotional stress, leads to sharply demarcated color changes of the skin.
- Classified clinically into primary or secondary forms.
- Primary RP is idiopathic and is associated with no identifiable abnormalities in blood vessel architecture.
- Secondary RP patients may have complications of digital tissue ischemia, including recurrent digital ulcerations, rapid deep tissue necrosis, and amputation.
- Avoidance of cold temperatures is critical in the management of RP. The entire body must be kept comfortably warm.
- Medications are indicated if there are signs of critical tissue ischemia (eg, digital ulcers) or if quality of life is restricted.
A unique circulatory system, including both thermoregulatory and nutritional blood vessels, exists in the skin, especially in the hands, feet, and the face. In these areas of the body, local blood flow is regulated by a complex interaction of neural signals, cellular mediators, and circulating vasoactive molecules. Temperature responses are principally mediated through the sympathetic nervous system by rapidly altering blood flow through arteriovenous shunts in the skin. During hot weather, these shunts open (vasodilate), allowing heat to dissipate. In cool weather, the shunts constrict, shifting blood centrally and helping maintain a stable core body temperature.
Raynaud phenomenon (RP) is transient digital ischemia due to cold temperatures or emotional stress. This vasoconstriction of digital arteries, precapillary arterioles, and cutaneous arteriovenous shunts leads to a sharp demarcation of skin pallor or cyanosis of the digits (Figure 24–1). The ischemic phase is followed by recovery of blood flow that appears as cutaneous erythema, secondary to rapid reperfusion of the digits.
A typical Raynaud phenomenon attack characterized by a sharp demarcation of skin pallor.
RP is classified into two categories: primary and secondary. Primary RP are vasospastic attacks precipitated by cold temperatures or emotional stress. Primary RP, which occurs in the absence of an identifiable disease, is most common in otherwise healthy females between 15 and 30 years of age. A family history of first-degree family members is reported in about 30% of cases. These attacks usually occur symmetrically and bilaterally in the hands. There is no underlying sign of tissue necrosis or gangrene (eg, digital pitting) and the underlying vasculature is normal. Nailfold capillary microscopy (see below) and physical examination findings are normal. If a patient meets criteria for primary RP and no new symptoms develop over 2 years of follow-up, the development of secondary disease is unlikely. The finding of abnormal nailfold capillaries on microscopy or specific autoantibodies are strong predictors of secondary RP due to an underlying rheumatologic disease.
Secondary RP is associated with an underlying pathology that alters regional blood flow by damaging blood vessels, interfering with neural control of the circulation, or changing either the physical properties of the blood or the levels of circulating mediators that regulate the digital and ...