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Chapter 42 Sickle Cell Disease 595

or oxygen desaturation, administer naloxone. Incentive spirometry Chronic Pain
and mandatory time out of bed are helpful in patients with chest pain Chronic pain in SCD usually (but not always) has an identifi-
to decrease the risk for hypoventilation. Adjuvant medications to able basis such as vertebral fractures, femoral head necrosis, early
consider include NSAIDs, acetaminophen, antiemetics, and antihis- degenerative changes or osteoarthritis, or chronic skin ulcers. Most
tamines. Laxatives or stool softeners should be prescribed in keeping patients without such identifiable complications do not require
with close monitoring for constipation. chronic pain medications similar to those used for terminal cancer
After 2–3 days, consider decreasing the dose and switching from because the pain from a typical vasoocclusive crisis is episodic.
parenteral to oral administration of opioids. For adult patients whose Inappropriately maintaining patients without chronic musculoskel-
pain requires several or many days to resolve, a sustained-release etal degeneration on long-acting opiates can impair their overall
opioid preparation is appropriate and provides a more consistent psychosocial functioning. On the other hand, adequate analgesia
analgesia. with long-acting opiates (e.g., long-acting morphine preparations
Hydration is a critical part of management. However, cardiac similar to those used in cancer patients) is important to maintain
function may be significantly impaired, especially in adult patients, the psychosocial functioning of patients who do have complications
and standard discipline must be followed with intravenous fluid that cause chronic pain. Also, consider agents such as amitriptyline or
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management to avoid iatrogenic fluid overload. Patients with SCD antiseizure medications that can address neuropathic components
cannot concentrate their urine and are at risk for dehydration when and help decrease the sleep impairment and depression that can occur
not taking adequate fluids (60 mL/kg/24 h in adults). Intravenous with chronic pain. If the patient is not taking a disease-modifying
hydration is indicated when the patient is not taking oral fluids agent such as HU, consideration should be given to initiating such
adequately. Ideally, the urine specific gravity should be kept under therapy.
1.010 by daily testing when in the hospital. Hb may decrease by
1–2 g/dL in an uncomplicated pain crisis; blood transfusion is not
routinely indicated for an uncomplicated pain crisis. Chronic Anemia
Equianalgesic doses of oral opioids should be prescribed for home
use when necessary to maintain the relief achieved in the emergency Chronic hemolytic anemia is one of the hallmarks of SCD. Sickle
department or hospital ward. Care should be taken to appropriately erythrocytes are destroyed randomly, with a mean life span of 17
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taper opioids in patients who have received daily opioids over many days. The overall hemolytic rate reflects the number of ISCs. The
days. In these patients, there may be physical opiate dependence, degree of anemia is most severe in sickle cell anemia, and Hb S–β°-
+
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which is characterized by the onset of acute withdrawal symptoms thalassemia, milder in Hb S–β -thalassemia and Hb SC disease,
upon cessation of opioid administration. For patients at risk for and, among patients with sickle cell anemia, less severe in those who
physical dependence, opiates should be titrated downward by 15% have coexistent α-thalassemia (Table 42.8 and see Table 42.1). 134
to 20% per day to zero. Physical dependence is a physiologic problem, As already noted, EPO deficiency from otherwise subclinical
but addiction is a psychologic problem characterized by craving— chronic renal damage may also contribute to a decline in Hb levels
behavior that is overwhelmingly directed at obtaining the drug; use below baseline. The level of chronic anemia is a significant prognostic
of the drug for purposes other than pain control; and use of the drug marker. 19
despite negative physical, social, legal, or psychologic consequences. The treatment options for the chronic anemia of SCD have
If the patient is not taking a disease-modifying agent such as HU, already been mentioned. These strategies attempt to decrease hemo-
consideration should be given to initiating such therapy either as an lysis by increasing Hb F (HU and the experimental approaches with
inpatient or during follow up in the outpatient setting. EPO, decitabine, and histone deacetylase inhibitors) or decreasing

TABLE Bacteria and Viruses That Most Frequently Cause Serious Infection in Patients With Sickle Cell Disease
42.8
Microorganism Type of Infection Comments
Streptococcus pneumoniae Septicemia Common despite prophylactic penicillin and pneumococcal vaccine
Meningitis Less frequent than in years past
Pneumonia Rarely documented except in infants and young children
Septic arthritis Uncommon
Haemophilus influenzae type b Septicemia
Meningitis
Pneumonia Much less common in recent years because
of immunization with conjugate vaccine
Salmonella species Osteomyelitis
Septicemia Most common cause of bone and joint
infection
Escherichia coli and other Septicemia
gram-negative enteric pathogens
Urinary tract infection
Osteomyelitis Focus sometimes not apparent
Staphylococcus aureus Osteomyelitis Uncommon
Mycoplasma pneumoniae Pneumonia Pleural effusions; multilobe involvement
Chlamydia pneumoniae Pneumonia
Parvovirus B19 Bone marrow suppression (aplastic crisis) High fever common; rash and other organ involvement infrequent
Hepatitis viruses (A, B, and C) Hepatitis Marked hyperbilirubinemia
Data from Buchanan GR, Glader BE: Benign course of extreme hyperbilirubinemia in sickle cell anemia: Analysis of six cases. J Pediatr 91:21, 1977.