Anti-D

Question 1

What % of Rh -ve women in pregnancy undergo sensitisation

Answer 1

1%

Question 2

What % of Caucasian women are rh-ve

Answer 2

15%

Question 3

How common is haemolytic disease of the newborn

Answer 3

1.6/100,000

Question 4

How long after a sensitising event should anti-D be given

Answer 4

Within 72hr but may have benefit up to 10days

Question 5

<20 weeks, how much anti-D should be given for a sensitising event

Answer 5

250iu

Question 6

> 20 weeks, how much anti-D should be given for a sensitising event

Answer 6

500iu

Question 7

If continued Pv bleeding, how often should anti-D be repeated

Answer 7

Every 6 weeks

250iu if 12-20 weeks
500iu if >20 weeks

Question 8

Advise

33/40 Attended with heavy pv loss on background of continued light pv bleeding since 22 weeks, last anti-D 3 weeks ago

Answer 8

Give 500iu

New sensitising event or change in pattern or additional pain in recurrent bleed should prompt repeat 500iu regardless of timing of last dose

Question 9

Regarding anti-D

When should testing for FMH be carried out

Answer 9

> 20 weeks

48hr after IV or 72hr after IM dose of anti-D

Question 10

Regarding anti-D

When should further dose be given and how should be the repay dose be calculated

Answer 10

If FMH >4ml further dose of anti-D is required

Give 125iu IM or 100iu IV for each 1ml over 4ml. Minimum of 500iu should be given

Repeat test for FMH 48hr later to ensure clearance

Question 11

When should routine anti-D prophylaxis be given and at what dose

Answer 11

Single dose at 1500iu at 28-30 weeks

Or

Two doses of 500iu at 28 and 30 weeks

Question 12

When is a direct antiglobulin test (DAT) performed

Answer 12

Post delivery if there is concern regarding haemolytic disease of the newborn

Question 13

Regarding fetal ABO & Rhesus status

When would a heel prick sample be taken

Answer 13

If cord bloods where not available

Question 14

Ho soon after delivery should maternal blood samples be take in Rh -ve women

Answer 14

> 30-45minutes

<2hr

Question 15

When should anti-d be given post delivery

What is the dose of anti-D

What further testing is required

Answer 15

If mother Rh -ve and baby Rh +ve

500iu anti D

Test for FMH 48hr after IV or 72hr after im

Question 16

What % of women have FMH <4ml following delivery

Answer 16

99%

Question 17

Regarding cell salvage

What is the volume of fetal RBC in reinfused blood

Answer 17

1-20ml

Question 18

Regarding cell salvage

If Rh -ve mum and Rh+ve baby, what is the minimum dose of anti D given

When should a sample for qualifying FMH be taken

Answer 18

1500iu antiD

30-45 minutes after re-infusion

Question 19

In a Rh -ve women, when following IUD should Anti-D be given

Answer 19

Within 72 hours of diagnosis

Question 20

If Rh -ve woman given Rh+ve platelets, how much anti-D should be given

Answer 20

250iu anti-D

Question 21

When should anti-D be given as s/c or IV rather than iM

Answer 21

If thrombocytopenia platelets <30 to avoid bleeding from IM injection

Question 22

How much antiD should be given if <15ml of Rh +ve RBC given to a Rh -ve woman

Answer 22

125iu anti-D

Question 23

What is the management if >15ml of Rh +ve RBC given to a Rh-ve woman

Answer 23

1500-2500 iu anti D IV

Use flow cytometry to quantify Rh+ve RBC 48hr after IV or 72hr after IM anti-D given

Question 24

What is the management if >1 unit of Rh +ve RBC given to a Rh-ve woman

Answer 24

Consider exchange transfusion

This will achieve 65-70% reduction in Rh+ve RBC.

85-90% reduction will be achieved with double volume exchange

Question 25

Into which muscle should IM anti-D be given

Answer 25

deltoid