CP107 Laboratory Methods for Detecting Fetomaternal Hemorrhage and Calculating the Dose of Rh Immune Globulin
9:30–11:30 am
2.0 CME CREDITS
This presentation will review current methods for quantifying fetomaternal hemorrhage in postpartum women and for calculating the dose of Rh immune globulin (RhIG) for postpartum Rh immunoprophylaxis. Most participants (>95%) in the CAP’s 2010 Surveys program for Fetal RBC Detection screened maternal blood for fetomaternal hemorrhage (FMH) using the rosette assay and quantified results using the acid-elution (Kleihauer-Betke) assay. Flow cytometry assays offer the promise of a more precise and reproducible quantification of fetal RBCs in maternal blood and, therefore, more accurate dosing of RhIG. Few hospital laboratories use flow cytometry for this purpose because of logistical impediments. This presentation will review the scientific basis and limitations of the rosette screen and K-B assay. It will also review the practical aspects of introducing flow cytometry assays to quantify fetomaternal hemorrhage. In the second hour, faculty will address different methods for calculating the recommended dose of RhIG for postpartum Rh immunoprophylaxis. Faculty will also review the benefits of using the CAP RhIG Dose Calculator and present examples.
You will learn to:
- Describe the scientific basis of the rosette screen for detecting fetomaternal hemorrhage
- Recognize technical limitations of the acid-elution (K-B) assay for quantifying FMHs
- Analyze your hospital’s laboratory services requirement for detecting FMH and for timely dosing of RhIG
- Evaluate whether the hospital’s requirements are adequately served by a rosette screen and acid-elution (K-B) assay or could be improved by introducing flow cytometry
Faculty
Jerome L. Gottschall, MD, FCAP
S. Gerald Sandler, MD, FCAP