The overall goal of this method for continuous manual exchange transfusion is to treat sickle cell diseased patients in need of chronic transfusions while limiting their iron overload without the use of special equipment. This method can help answer key questions in the field of sickle cell anemia, about how to safely and efficiently perform chronic exchange transfusions when electrophoresis is not available. The main advantage of this technique is that it can be performed without specific equipment, but still maintain a similar efficiency to electrophoresis.
Visual demonstration of this method is critical and the continuous phlebotomy steps must be strictly controlled and supervised. Before beginning the exchange transfusion session, have a physician perform a thorough and complete physical examination of the patient, paying specific attention to the body temperature and the hemodynamic parameters and obtain a recent body weight. Install a peripheral venous line to one limb for the phlebotomy and a second venous line to the other limb for the albumin and packed red blood cells infusion.
Then administer one gram of calcium per OS to prevent hypocalcemia due to the presence of a calcium chelating anticoagulant in the transfusion bags. After the results of the exams have been checked, obtain the initial phlebotomy volume using the table as a guide for determining the volume and rate of the acquisition. Program the infusion of the same volume of albumin solution in the syringe pump.
Before beginning the initial phlebotomy, confirm that the appropriate volume of phenotypically-matched packed red blood cells is available at the blood bank for the exchange transfusion. Carefully confirm the compatibility of each delivered blood bag. Just prior to the exchange transfusion, place the patient in the supine position with the feet slightly raised and administer one liter of oxygen via a nasal cannula.
If the patient's hemoglobin level is greater than 8.5 grams per deciliter, begin an initial isovolemic phlebotomy by infusing the 5%albumin solution. After 20 to 50 milliliters of albumin have been infused, unclamp the peripheral intravenous access connected to an empty bleeding bag located below the patient's bed and begin the phlebotomy at the same rate as the albumin infusion. Monitor the patient every five minutes during the initial isovolemic phlebotomy.
If the blood flow is too low, raise the bed to increase the height difference between the arm and the bleeding bag and consequently the blood flow. As the blood is collected, weigh the bleeding bag on a precision scale to adapt the infusion flow in real time to compensate for the volume of blood. At the end of the phlebotomy, use a hemoglobin point of care test to check the hemoglobin levels according to the manufacturer's instructions to confirm that the hemoglobin is around eight grams per deciliter.
For the isovolemic exchange transfusion, begin by transfusing the first 20 milliliters of diluted packed red blood cells before starting the phlebotomy at the same rate of infusion. Monitor the patient every 15 minutes. If the hemoglobin level is higher than 9.5 grams per deciliter, perform an additional phlebotomy compensated by an infusion of the same volume of albumin solution.
At the end of the exchange transfusion, perform the appropriate laboratory tests for determining hemoglobin, hemoglobin S, and calcium levels. Then administer one more gram of calcium per OS, keeping the patient under surveillance for at least one hour after the end of the exchange. As expected, in this representative experiment, the pediatric patients who received electrophoresis only exhibited a very stable ferritinemia.
By comparison, the iron overload generated by a program of chronic red blood cell transfusions was approximately four times greater than that observed under the erythropheresis program. If only patients who received the manual exchange transfusion by the continuous method are considered, a quite stable ferritinemia with an almost equivalent control of iron overload as with erythropheresis is observed. After watching this video, you should have a good understanding of how to perform continuous manual exchange transfusion as a safe and effective alternative for sickle cell patients who need chronic transfusions.
