Blood transfusion, hydroxyurea useful in managing sickle cell disease
SAN DIEGO — Although there is no simple cure for sickle cell disease, blood transfusion and hydroxyurea are two modifying therapies that can be used to manage the disease, according to a presentation at the ACP Internal Medicine Annual Meeting.
Health maintenance is crucial in treating patients with sickle cell disease, Jennifer Yu, MD, from Rady Children’s Hospital in San Diego, said during her presentation. Clinicians should take measures to prevent infection and screen or monitor for pulmonary hypertension in patients with symptoms such as fatigue and shortness of breath, she said.
Managing acute pain crisis
The main focus for managing a patient with sickle cell disease with painful vaso-occlusive crisis is controlling their pain as quickly as possible through very rapid initiation of IV opioids or pain medications, Yu said.
Frequent reassessment is essential to ensure that the pain remains controlled, she said. If the patient’s pain is not under control, clinicians should administer additional pain medication, she said.
“Patients who receive scheduled around the clock pain medication via IV or oral opioids do better and have decreased duration in stay in the hospital, as well as decreased pain scores when compared to providing pain management on an as needed basis,” Yu said.
Patients requiring many additional frequent doses of IV pain medications may benefit from patient-controlled analgesia, she said.
Keeping the patient hydrated is very important, she said. Clinicians should give maintenance IV hydration to avoid over-hydrating while providing enough fluid to dilute out sickle cells, she said.
Yu also said that incentive spirometry is important during an acute pain crisis. Patients should use an incentive spirometer every 2 to 4 hours that they are awake to keep their lungs open, she said.
Other supportive care that can be used to manage patients with acute pain crisis include complementary medicine, biofeedback, therapists or even heat packs, she said.
Modifying therapies in sickle cell disease
Disease-modifying therapies for sickle cell disease include blood transfusion and hydroxyurea, according to Yu.
“If used in the right situation, blood transfusion can be lifesaving,” she said. “The idea behind giving a blood transfusion for sickle cell disease is to change or modify the patient’s complications, give back normal red blood cells with normal hemoglobin and dilute out that hemoglobin S percentage.”
Patients are less likely to experience sickle cell complications when they have less hemoglobin S, she said.
Immediate complications of blood transfusion that clinicians should monitor include allergic or febrile reactions, she said. Delayed hemolytic transfusion reaction, which can occur 1 to 4 weeks after the transfusion, is another complication that clinicians should be aware of, she said.
For primary or secondary stroke prevention and to keep a patient’s hemoglobin S percentage low, clinicians should use chronic transfusion protocol; however, in such cases, iron overload can be an issue, she said. Iron can permeate into organs such as the liver and heart which can cause arrhythmias and potentially be fatal, she added.
Alloimmunization in patients with sickle cell disease can make blood transfusions ineffective, according to Yu. To avoid alloimmunization, clinicians should give patients receiving a blood transfusion phenotypically matched blood, she said.
Exchange transfusion can be very helpful in patients with sickle cell disease who have severe symptomatic acute chest syndrome or multisystem organ failure because it lowers the percentage of hemoglobin S more quickly, increases the percentage of normal hemoglobin faster, increases transfusion volume and decreases iron overload, Yu said. However, there are also risks including increased donor unit exposure, alloimmunization, permanent central line access and the requirement of specialized equipment, she said.
“Blood transfusion is not a completely benign process, so it’s important to recognize the situations in which it is not indicated, which include uncomplicated pain crisis, asymptomatic anemia and priapism,” Yu said.
Hydroxyurea is used to increase hemoglobin F level in patients with sickle cell disease. It has effects similar to blood transfusion, including decreasing hemolysis and inflammation and improving tissue oxygenation, Yu said. The most common side effect of hydroxyurea is bone marrow suppression. To ensure that patients’ bone marrow is not suppressed, clinicians should emphasize to patients receiving hydroxyurea that they need to be compliant with follow-up visits, she said.
Yu indicated that it can be difficult to decide whether to start hydroxyurea. Patients who would benefit most from hydroxyurea therapy include adults who have experienced three or more pain crises in one year, adults with sickle cell anemia, patients with severe pain or anemia that interferes with daily activity and quality of life, and patients with severe acute chest syndrome or recurrent acute chest syndrome.
“Blood transfusion and hydroxyurea are the only disease-modifying therapies that we have for sickle cell disease,” Yu said. “There is no easy cure, unfortunately. The only cure we have is bone marrow transplantation, but there are many complications that come along with that. It is certainly not used as first-line therapy. There are many trials going on right now, including the Gene Therapy trials, that are looking into other management techniques for acute pain crises and trying to reduce the amount of time that patients spend in the hospital. I hope that in a few years when we’re talking about therapies in sickle cell disease and new guidelines that we’re able to offer gene therapy. It is looking very promising.” – by Alaina Tedesco
Yu J. MTP 031: Sickle Cell Disease: New Guidelines for Therapy. Presented at: ACP Internal Medicine Annual Meeting; March 29-April 1, 2017; San Diego.
Disclosure: Yu reports no relevant financial disclosures.