Sat, May 12, 2012

Cyanosis

Cyanosis refers to a blue discoloration of the skin. Cyanosis in children and infants is often caused by serious heart defects.

What is cyanosis?

Cyanosis refers to a blue discoloration of the skin. Hemoglobin is the molecule found in red blood cells which is responsible for carrying oxygen. When oxygen is bound to hemoglobin, blood has a red color. When oxygen is released from hemoglobin, blood turns a blue color. Cyanosis most commonly is caused by a lower than normal oxygen saturation of hemoglobin in the blood.

What causes cyanosis?

Usually cyanosis in children is caused by either a heart or lung problem. Problems with the lungs cause cyanosis because oxygen is not effectively delivered from the lungs into the bloodstream. Most children with cyanosis caused by lung problems tend to show signs of rapid breathing and respiratory distress. They often breathe much quicker than normal and in some cases struggle to breathe. In children with lung causes of cyanosis, giving supplemental oxygen usually causes the cyanosis to resolve quickly.

Heart problems that cause cyanosis tend to do so by allowing blood to bypass the lungs completely. Cyanotic heart defects such as tetralogy of Fallot, tricuspid atresia, pulmonary atresia, and transposition of the great arteries result in significant cyanosis because the blood bypasses the lungs completely and returns immediately back to the body. Children with cyanosis caused by a heart problem often appear relatively calm. They typically do not struggle to breathe, as children with cyanosis from lung problems do. In addition, the administration of oxygen usually does little to change the degree of cyanosis. Because the blood is not entering the lungs in the first place, adding extra oxygen does no good.

Some children may present with what is called acrocyanosis. Acrocyanosis is not true cyanosis. In acrocyanosis, the blood oxygen level in the arteries is normal. Acrocyanosis is usually caused by prominent venous dilation creating a blue tint to the skin. Acrocyanosis is commonly seen in newborn infants who have immature nervous system control of the peripheral blood vessels.

How is cyanosis diagnosed?

When an infant presents with cyanosis, a diagnosis must be rapidly made. One of the first clues is the response to supplemental oxygen. If the cyanosis resolves quickly, this usually suggests a lung cause. If the cyanosis does not resolve, this suggests the possibility of a cardiac problem. If a cardiac problem is suspected, an echocardiogram is usually performed to rule out the presence of a serious cyanotic congenital heart defect.

With the treatment for cyanosis?

Treatment of cyanosis depends on the underlying cause. Lung causes of cyanosis require supplemental oxygen and treatment of the lung problem causing the issue in the first place. Treatment of heart causes of cyanosis depends on the exact heart problem. Many of these children require the administration of prostaglandin, a medication designed to keep the ductus arteriosus open as a means to allow extra blood to enter the lungs. Ultimately surgical correction of the heart defect may be necessary to cure the cyanosis.

In summary, rapid diagnosis of the underlying cause of cyanosis is important for a good outcome. Fortunately in this day and age this is usually possible with advanced technology such as echocardiography, as well as well-prepared practitioner.