Pathologic Conditions
- Definition: A hereditary, chronic form of anemia in which normal hemoglobin is partly or completely replaced by abnormal hemoglobin.
- Pathophysiology: Under conditions of dehydration or deoxygenation, red blood cells begin to sickle (assume an odd or irregular shape). These cells carry oxygen poorly and are very fragile, resulting in early cellular destruction. The irregularly shaped cells rupture or become enmeshed with one another, clogging vessels and causing tissue necrosis and pain ("pain crisis" or vaso-occlusive crisis). Major organs such as the spleen, liver, kidneys, and brain may be damaged.
- Etiology: The disease is an inherited autosomal recessive disorder; that is, both parents must be carriers. In the United States, about 1 in 12 African-Americans carries the gene (carriers are said to have the "trait").
- Manifestations: Hemoglobin S in blood, anorexia, increased susceptibility to infection, small for age, and short trunk and long extremities in older child. "Pain crisis" is manifested by pain (frequently in extremities and abdomen), respiratory distress, and fever.
- Med Tx: Goal is to prevent increased sickling and crisis. Daily fluid intake should be at least 1½ times normal maintenance amount (see Pediatric Maintenance Fluid Calculation). Patient is taught to avoid deoxygenation and resultant crisis by avoiding strenuous exercise, high altitudes, infection, and chilling.
- Nsg Dx: Pain, altered tissue perfusion, altered growth and development, potential for infection, constipation related to analgesic use, knowledge deficit, support.
- Nsg Care: Force fluids to 1½ times normal maintenance (see Pediatric Maintenance Fluid Calculation). Monitor need for analgesics. Monitor urine and bowel elimination. Prevent infection. Teach pain crisis prevention. Support.
- Prognosis: Mortality rate is about 25% during childhood. Crises are usually less frequent and prognosis is better for adults.