What is Acrocyanosis?
Acrocyanosis is the persistent bluish discoloration of the extremities including the hands, feet and parts of the face, but the most common is cyanosis of the hands. Acrocyanosis occurred some 100 years ago, but the nature of the condition is still unclear. Acrocyanosis has been thought to be similar with other conditions involving the cyanosis of extremities such as frostbite, reynaud’s disease, erythromelalgia, pernio and blue finger syndrome. However, acrocyanosis is not the same as to the pathophysiological mechanism. The extremities may also be persistently cold and cyanotic. Swelling and sweating of the extremities may also be present. Unlike other arterial occlusive disorders, acrocyanosis is not painful, ulcers and changes in the skin integrity also do not occur.
Acrocyanosis in Newborn
Acrocyanosis is commonly seen in newborns, whether preterm or full term. The phenomenon is considered normal to newborns because of immature circulation and underdeveloped capillaries. Acrocyanosis is one assessment in the early stages of newborn life especially during the first five minutes of life. Acrocyanosis may be present upon delivery of the newborn, but disappears after five minutes of spontaneous respirations. However, some institutions provide supplemental oxygen as precautionary measures for any underlying congenital problems.
Observe Blue discolored hands and foot in acrocyanosis in newborn
Acrocyanosis in Infants
When babies grow, the circulation normally develops and infants do not usually present acrocyanosis. When acrocyanosis in infancy is still persistent, further evaluation should be done to check for congenital anomalies such as heart problems.
The exact etiology of acrocyanosis is unknown, but a benign neurohormonal condition may cause the disease. The condition results in narrowing of the arterioles on the proximal part of the extremities leading to cyanosis and cold, clammy skin.
When the arterioles go into vasospasms, the arteries and arterioles produce cyanosis. The persistent vasoconstriction in the area creates a local hypoxic atmosphere, which releases adenosine into the area. Because of vasospasm, adenosine enters the capillaries and causes vasodilation of the venules. The dilatation of the venules and constriction of the arterioles creates a countercurrent exchange system that causes heat to be retained. When this happens, profuse sweating of the palms and soles may occur as a result of excessive heat retention. Dilation of the veins also increases capillary permeability leading to extravasation of plasma into the interstitial space causing edema of the affected part.
Aside from adenosine, increase in serotonin also plays a role in acrocyanosis although the exact mechanism is not understood. Children taking Selective Serotonin Reuptake Inhibitors (SSRIs), a type of antidepressant, have manifested acrocyanosis as one of the side-effects. Other medications may also lead to acrocyanosis.
Acrocyanosis should not be seen as a serious condition, but precautionary measures and consultations should be taken as this may be caused by other underlying diseases.
Acrocyanosis Causes and Risk Factors
Exact mechanism of acrocyanosis is unknown. It is considered a benign neurohormonal disorder that causes narrowing of the arterioles at the upper and lower extremities.
Acrocyanosis is more common in children and young adults and the prevalence is also greater in women than in men. Studies suggest that risk factors to acrocyanosis include working outdoors, cold climate, and a low body mass index. Low body mass index explains why children, young adults and women have higher risk in developing it. The occurrence of acrocyanosis decreases with age regardless of the climate.
Types of acrocyanosis
Acrocyanosis types depend on the causative factor.
1. Primary acrocyanosis
Primary acrocyanosis is the occurrence of the phenomenon without underlying cause or disease. These may be seen on newborn and young children with no apparent pathological condition that may lead to acrocyanosis.
2. Secondary Acrocyanosis
This type is usually caused by pathologic conditions such as arterial occlusive diseases in adults and heart anomalies in children and the newborn.
Acrocyanosis Symptoms and Signs
Acrocyanosis is seen as consistent bluish to purplish discoloration of the hands and extremities. Other signs and symptoms of acrocyanosis include:
- Symmetrical discoloration of the hand and feet
- Cold, clammy extremities
- Swelling of the extremities
- Sweating on the palms and soles which may be moderate to profuse
Despite those, people with acrocyanosis often have normal rate, amplitude and rhythm of peripheral pulses. Pain is also not present as compared to other occlusive diseases. The absence of pain and presence of normal pulses indicate that there is no significant problem on the circulation. Some individuals are asymptomatic, except from bluish to purplish discoloration of the hands and feet, which prompt them to seek consult and treatment knowing that it is a sign of a serious illness.
Diagnosis of acrocyanosis involves extensive medical history and physical assessment. Other laboratory and imaging test is often not required. Presence of normal characteristics of pulses helps in ruling out the occurrence of arterial occlusive and peripheral artery diseases, such as Reynaud’s phenomenon. In occlusive diseases, the arteries are obstructed or narrowed which leads to impairment in the circulation.
- Pulse oximetry also indicates a normal oxygen saturation of 95 to 100%. In people with peripheral arterial diseases, oxygen saturation results are commonly lower than 95% as a sign of hypoxia to the area.
- Aside from the pulses and oxygen saturation, the skin is also observed for trophic changes. Acrocyanosis does not lead to skin changes and ulcers, aside from the cyanotic discoloration.
- Some may require other tests such as capillaroscopy (visualization of the capillaries) to arrive in a definite diagnosis especially when connective tissue disorders are also present.
Since acrocyanosis is not a disease, there is no definite treatment for it, although the following may help reduce the symptoms:
Prevention of Cold
The primary treatment is prevention of cold to avoid vasoconstriction and promote proper circulation.
Sympathectomy is a surgical procedure that destroys the nerves in an area that innervates the sympathetic nervous system. It is done in acrocyanosis to promote vasodialtion. However, it is rarely done because it is an invasive procedure and acrocyanosis really do not cause significant diseases.
Calcium channel blockers and alpha adrenergic blockers (antihypertensive medications) become an option for the management, although it is not concurrently used. One study reveals that vasoactive drugs have little evidence that they are effective in the management of primary acrocyanosis which led to doctors not prescribing the drug.
The management of acrocyanosis simply focuses on the avoidance of cold. Health practitioners should also explain to patients that acrocyanosis without underlying arterial occlusive disease is not a medical emergency. It only needs supportive management.
Acrocyanosis often do not lead to complications and there is an excellent prognosis. The cause is benign which means no further developments of the disease is likely to occur. However, when acrocyanosis co-exists with other arterial occlusive diseases, then complications of the underlying conditions may arise such as skin ulcerations, infection and even amputation. Unless acrocyanosis occur from another condition, there is no possible risk for complications and disease. Patients can expect to have a normal life. Secondary acrocyanosis treatment also depends on managing the underlying cause.
Although acrocyanosis has not been found to directly be caused by certain factors, prevention can still be implemented. Prevention for acrocyanosis includes the following:
- 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.
- 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.
- Massage the hands and feet. – Massage relaxes the muscles and the underlying blood vessels thus preventing vasospasms
- 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.