Post Transfusion Labs - page 2

How long after a blood transfusion does your instituion wait to do a followup HH and what is the rationale? I've heard conflicting answers from one to two hours, to it doesn't matter. If the... Read More

  1. by   Sunflowerinsc
    Quote from duck1978
    We usually get an H&H 2 hours post transfusion unless the MD orders differently. My real question is about the Lasix post transfusion. Does the line have to be free of blood to push the Lasix? How long do you wait before pushing the Lasix? Thanks.
    If the lasix is to be given after the transfusion is finished, the blood tubing set would be taken down. If pt's b/p ,resp,lung sounds are ok,go ahead and give it. We give Lasix push, flush hep lock ,push Lasix over time needed for the dose you are giving ,flush. If fluids are ordered post transfusion ,hang the solution ordered with new IV tubing.

    We give alot less transfusions for anemia now days,generally blood bank requests Hem 7 or below unless pt has active bleeding. Some of the Doc's still don't like it but after work up is finished may order IV iron infusions daily.
  2. by   NHSbaseball32
    We normally wait about an hour depending on the doc. The rationale for waiting is to give the pc's plenty of time to circulate and mix in with the blood already in the circulatory system. Drawing an h/h too soon could possibly give false results.
  3. by   SpikeSpartan
    A. Optimum timing of post-transfusion phlebotomy is critical for ensuring meaningful laboratory testing results, and medical judgment is required in making this determination. Several factors must be considered, including the type and amount of blood product given, purpose of the test (that is, the question it is intended to answer), and clinical setting.
    In general, it is best to perform phlebotomy when the patient's circulatory system is in homeostasis. A patient who is bleeding or undergoing blood product transfusion, or both, is not in a steady state. Whenever possible, samples for laboratory testing should be postponed until bleeding has stopped and transfusion is complete. One obvious exception to this rule, however, would be the setting of massive transfusion, during which monitoring certain laboratory values, such as cell counts and coagulation parameters, is essential to guide ongoing therapy. Variables such as patient blood volume, cardiac output, renal function, and volume of blood products transfused affect how quickly homeostasis is achieved following transfusion.
    For the evaluation of post-transfusion increments in hemoglobin, hematocrit, and platelet counts, a practical approach is to draw blood samples within 10 to 60 minutes after completing transfusion, as this time interval is aimed at measuring peak recovery.1 Results determined from blood samples drawn later than 60 minutes post-transfusion are increasingly affected by confounding conditions, such as splenic sequestration, sepsis, and consumption.1,2 If the intent is to determine the extent of such confounding processes on red cell and platelet counts, one should combine a 10-minute post-transfusion sample with sequential samples drawn at one hour and 24 hours post-transfusion.
    Alterations in chemistry test results following transfusion are not usually a concern in the low-volume transfusion setting. However, assay results may be affected for varying periods following transfusion of large amounts of blood products, as seen in massive transfusion, red cell, or plasma exchange--particularly if the recipient has impaired hepatic or renal function. Banked storage of red cells results in elevated plasma levels of hemoglobin, potassium, LDH, and iron in the blood unit that may, particularly in the metabolically impaired patient, be reflected in the post-transfusion laboratory values. In addition, citrate anticoagulant present in blood products may result in transient hypocalcemia in the recipient.3 Therefore, following large-volume transfusions or exchanges, waiting 12 to 24 hours before drawing samples for chemistry assays will provide results that are more reflective of the patient's underlying metabolic state.
    1. Choo Y. The HLA system in transfusion medicine. In: McCullough J, ed. Transfusion Medicine. New York, NY: ­McGraw-Hill Book Co;1998:401.
    2. Legler TJ, Fischer I, Dittman J, et al. Frequency and causes of refractoriness in multiply transfused patients. Ann Hematol. 1997;74:185-189.
    3. Brecher ME, ed. Technical Manual. 15th ed. Bethesda, Md.:AABB;2005;649-650.