Acrocyanosis

Definition

Definition of Acrocyanosis
Acrocyanosis refers to a persistent blue or cyanotic discoloration of the extremities, most commonly occurring in the hands although also occurring in the face and feet as well. The principal form of acrocyanosis is that of a benign cosmetic condition, sometimes caused by a relatively benign neurohormonal disorder. Regardless of its cause, the benign form typically does not require medical treatment. A medical emergency would ensue if the extremities experience prolonged periods of exposure to the cold, particularly in children and patients with poor general health. However, frostbite differs from acrocyanosis because pain (via thermal nociceptors) often accompanies the former condition, while the latter is very rarely associated with pain.

Symptoms

Symptoms of Acrocyanosis
Acrocyanosis is characterized by peripheral cyanosis: persistent cyanosis of the hands or of the hands, feet, or face. The extremities often are cold and clammy and may exhibit some swelling. The palms and soles exhibit a wide range of sweating from moderately moist to profuse, but all peripheral pulses should have normal rate, rhythm, and quality. Exposure to cold temperatures worsens the cyanosis, while it often improves on warming. Patients normally are asymptomatic and therefore there is usually no associated pain; the most common sign, discoloration, usually is what prompts patients to seek medical care.

Causes

Causes of Acrocyanosis
The precise etiology of acrocyanosis is unknown. The current line of thinking goes that vasospasms in the cutaneous arteries and arterioles produce cyanotic discoloration, while compensatory dilatation in the postcapillary venules causes sweating. Persistent vasoconstriction at the precapillary sphincter creates a local hypoxic environment, thus releasing adenosine into the capillary bed. Vasospasms force adenosine to enter the capillary bed, where it vasodilates the postcapillary venules. Such differences in vessel tone create a countercurrent exchange system that attempts to retain heat.

Diagnosis

Diagnosis of Acrocyanosis
Acrocyanosis is diagnosed clinically, based on a medical history and physical examination; laboratory studies or imaging studies are not necessary. The normal peripheral pulses rule out peripheral arterial occlusive disease, where arterial narrowing limits blood flow to the extremities. Pulse oximetry will show a normal oxygen saturation. Unlike the closely related Raynaud's phenomenon, cyanosis is continually persistent. In addition, there is usually no associated trophic skin changes, localized pain, or ulcerations.

Treatment

Treatment of Acrocyanosis
There is no standard medical or surgical treatment for acrocyanosis, and treatment, other than reassurance and avoidance of cold, is usually unnecessary. The patient is reassured that no serious illness is present. A sympathectomy would alleviate the cyanosis by disrupting the fibers of the sympathetic nervous system to the area. However, such an extreme procedure would rarely be appropriate. The same effect could be accomplished with ?-adrenergic blocking agents or calcium channel blockers.

Prevention

Prevention of Acrocyanosis
Although acrocyanosis has not been found to directly be caused by certain factors, prevention can still be implemented. Prevention for acrocyanosis includes the following:

1. Avoid cold temperatures: Cold temperature leads to constriction of the arterioles and possibly causes acrocyanosis. Stay inside during cold weather and wear appropriate clothing and gear such as gloves, boots, and coat.
2. Engage in exercise: Exercise promotes good circulation and oxygenation of cells. Concentrate on the upper and lower extremities. Avoid constrictive clothing, stockings or shoes. Promote proper circulation by ensuring that the extremities are relaxed. Use support stockings to enhance venous return and arterial blood flow.
3. Massage the hands and feet: Massage relaxes the muscles and the underlying blood vessels thus preventing vasospasms
4. Avoid Stress: Stress stimulates the sympathetic nervous system which further leads to fight and flight response. Vasoconstriction occurs because of this. Learn some stress reduction activities such as guided imagery, focused breathing, gardening, interacting with other people and even avoidance of the stressor.