– 25th September 2020.
- 1. Whichever lab is used for titration of Rh antibody titres, once ICT comes positive, check whether the titres are verified by Tube agglutination method rather than column method.
Most labs have facilities for both but prefer to do the initial screening on the column method. An antibody screening panel test should be done straight away.
Best would be that as soon as ICT comes positive to refer to a fetal medicine unit
- 2. The follow -up for ICT positive women is 2 weekly scans in a fetal medicine unit for MCA PSV.
The follow-up for Rh negative, but ICT negative is ICT blood checks every 4 weeks from 20 weeks onwards, apart from the booking bloods ICT . This will avoid late referrals for blood transfusion when the fetus is already in heart failure.
- 3. Timing of subsequent transfusion after the initial in utero transfusion will be monitored by the cut-off of MCA PSV >1.5 MoM or rate of fall of hematocrit. Increasing the threshold to 1.69 MoMs (as suggested by a few papers) will miss a significant number of anaemic fetuses.
- 4. A lot of cases of isoimmunization happen even in women who have received prophylactic Anti-D injections. This could be secondary to inadequate doses, incorrect timing of prophylactic doses or faulty storage.
- 5. All Rh negative women who are ICT negative at 28 weeks, should receive full dose prophylaxis between 28-30 weeks and then at delivery in Rh positive babies.
- 6. Ideally a Kleihauer -Betke should be checked post delivery and additional doses be given if feto-maternal haemorrhage is deemed to be beyond the neutralization effects of the standard dose.
- 7. In peripheral areas, please check that your supplier has maintained the cold chain for Anti-D procurement and storage.