MRCOG PART 2 SBAs and EMQs
Course PAID | ||
notes | 337 | |
EMQ | 1500 | |
SBA | 2111 |
Essay 280 - Rhesus disease
Essay 280 - Rhesus disease |
Posted by Farrukh G. |
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A healthy 29 year old woman in her third pregnancy is found to have raised anti-Rhesus D antibodies at 28 weeks gestation. (a) Evaluate the subsequent assessments that could be undertaken. [15 marks] (b) Discuss the antenatal management of fetal anaemia secondary to Rhesus disease at 28 weeks gestation. [5 marks] |
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Posted by amina . |
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Reveiw of her case notes should be done to look for previous pregnancies and their outcome like hydrops fetalis may indicates previous affected pregnancy. check if she has received anti D in last 8 weeks as passive anti D can be detected upto 8 weeks in maternal blood. she should be asked whether previous pregnancies were affected by rhesus alloimmunization .it helps in counselling the woman as severity of disease increases with parity. referral to specialist fetal medicine unit for further assessments should be made . serial anti D antibody titres by indirect Coombs test or quantification using auto analyser every 2weeks should be done .if levels are below 4 iu/ml , severe anemia of fetus is not expected. fetal anemia is rare below 10-15 iu/ml. Above 15 iu/ml there is high risk of fetal hydrops. Non red cell antibodies like anti Kell , Anti c and Anti E are also checked to assess risk of hemolytic disease of fetus and newborn (HDFN) father blood group testing and genotype testing should be done.if father is Rh positive , then genotyping to know homozygosity or heterozygocity should be done. homozygous status means most babies are effected and at the risk of HDFN , while heterozygous means 50% babies are at the risk of HDFN. fetal blood group testing by non invasive cell free fetal DNA found in maternal plasma is carried out .it is 96% sensitive test . repeat testing may be required if Rh negative as fetus will be only effected if Rh positive. invasive methods like amniocentesis can be carried out . it carries risk of further alloimmunization . fetal monitoring by middle cerebral artery peak systolic velocity MCA PSV for fetal anemia. if it is more than 1.5 multiple of median for specipic gestational age indicates moderate to severe fetal anemia . it has 100% sensitivety with 12% false +ve rate . it is carried out weekly for monitoring fetus at high risk of developing HDFN . ultrasound is undertaken to find hydrops fetalis that indicates poor prognosis. ultrasound will detect reduced fetal movements ,but severely anemic fetus may not develop hydrops and reduced fetal movements . CTG is not good predictor of HDFN .sinosidal pattern is rare even in severe anemic fetuses . amniotic fluid taken by amniocentesis ,is checked for bilirubin level and using spectral analysis at wave length 450nm , the amount of bilirubin is compared with uneffected pregnancies . liley 's graph is drawn for this purpose , if value reaches liley's zone 3 , fetal blood sampling is needed. amniocentesis is associated with fetal hemorrhage , infection and preterm rupture of membranes . it may boost maternal antibodies. fetal blood sampling if MCA PSV indicates anemia , is required.it is direct accurrate diagnosis of fetal anemia and acidosis . it carries risk of fetal loss 1-3% per procedure .blood is taken from either placental cord insertion site or intrahepatic vein.
(b) Discuss the antenatal management of fetal anaemia secondary to Rhesus disease at 28 weeks gestation. [5 marks] management involves referral to fetal specialist medicine unit . weekly MCA PSV measurements to detect the severity of anemia. in cases of moderate to severe anemia or if hematocrit is below 30% inutero fetal blood transfusion is carried out. packed O RH Negative cells compatiable with both mother and fetus are transfused . transfusion to supranormal levels of HB provides longer intervals between transfusions ( 2-4wks ) . intravascular route is preferred , however it can be done by intraperitoneal route. fetal loss rate per procedure is about 2-4% . plan for delivery at 34-36wks. other treatments like plasmaparesis and maternal immunoglobulin therapy have limited efficacy.
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Posted by Ghida R. |
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A healthy 29 year old woman in her third pregnancy is found to have raised anti-Rhesus D antibodies at 28 weeks gestation. (a) Evaluate the subsequent assessments that could be undertaken. [15 marks] (b)
I need to check her booking blood test if available to check her antibody status. if she had a negative indirect coombs test and now its positive, I will check whether she had any vaginal bleeding, abdominal trauma or invasive procedure like amniocentesis and whether there she received adequate anti D prophylaxis after each event. A recent antiD prophylaxis i.e. within the past 6 weeks, may cause the patient to have a high anti D titre. Also undiagnosed fetomaternal bleed occuring in between booking test and 28 weeks and that was not managed by admnistration of anti D will be a cause for sensitisation of the mother and development of high antibody titers. I need to check history of blood transfusions as inadvertant transfusion of rhesus positive blood may lead to maternal sensitisation. I will check if she has history of previous baby wth hydrops or stillbirth, as hydrops tends to recur in 90% of cases and is likely to occur earlier and be more severe. The mother should have her BP checked and whether she has edema, as in mothers of hydropic babies, there is mirror syndrome in which the mother will be edematous like her baby or suffers preeclampsia. Increase in symphisiofundal height may be an indirectly point to polyhydramnios which occurs due to fetal anemia and hyperdynamic fetal circulation, before hydrops develops. A repeat testing of anti D level will be needed to ascertain if the level is rising. The father blood group should be obtained and analysed for genotyping to check if the father is heterozygous for D antigen it means that the child has a 1in 2 chance of being rhesus negative. Alternatively if there is facilities for cell free fetal DNA in maternal blood this will detect if the fetus is rhesus positive or not. If the baby is rhesus negative this will obviate the need for invasive fetal testing. An ultrasound will check for fetal viability, presence of polyhdramnios. Presence of fetal ascitis means that the babies suffers from severe anemia about 1/3 of what its level should be. Fetal skin edema is a late sign of anemia. The placental size will also be enlarged due to hydrops. Fetal tructural anomalies should be checked as these may cause also hydrops. Amniocentesis is an invasive method and with potentially more sensitising effect to the mother, and was used to obtain amniotic fluid to test for indirect bilirubin level by spectrophotometer at deltaOD 450 wavelength. Repeated samplings was needed to detect when the level rises to zone 3 on Liley's cureve, which means severe anemia. This has now been replaced by Middle cerebral artery peak systolic velocimetry MCA PSV whick is a doppler flow that measures the velocity at which blood circulate in fetal brain. In fetal anemia there will be rapid circulation and a higher MCA PSV >1.5 multiple of median will indicate severe anemia. It has a 100% sentivity and 12% false positive. Percutaneous Umbilical blood sampling PUBS is an invasive procedure that will allow checking fetal blood count, blood group, direct Coombs test, TORCH studies if suspected. I will also allow for transfusion of the baby. It has risk of pregnancy loss of 1-2% in uncomplicated pregnancies. rising to 5 % if hydropic baby. It may also be associated with fetal bradycardia, hematoma of the cord and even fetal demise. After viability this should be done in facilities for urgent cesarean delivery if any of these complications arise.
Discuss the antenatal management of fetal anaemia secondary to Rhesus disease at 28 weeks gestation. [5 marks]
This patient should be managed in a specialised Maternofetal Center with expertise in managing this condition. A multidisciplinary team will be involved including: consultant obstetrician, specialised midwife, Maternofetal specialist, neonatologist. the patient will be seen every 1-4 weeks depending on clinical condition and previous obstetrical history. Her antiD level should be followed every 2 weeks to detect for rising titers or high titers >4IU/ml which put her as" high risk" and require more close monitoring. MCA PSV should be done fortnightly and if rising titers it can be done weekly or twice weekly. When MCA PSV reaches 1.5 MoM this will be an indication for fetal blood sampling to detect fetal hemoglobin and to transfuse if HB <30. This should be planned by giving patient antenatal corticosteroids, preparing Onegative blood cross matched with the mother's blood, alerting the operating theater in the event of urgent delivery. Transfusion to supranormal levels HB 40-50% will allow longer intervals between transfusions. Delivery should be planned at 36-38 weeks depending on fetal condition. |
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RH ESSAY |
Posted by safwa mohamed el sayd E. |
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I will take detailed history including previous baby delivered with RH disease &time passed since that pregnancy. Tha loger the duration the stronger the response with high quality & quantity of antibodies. I will chech the titre ,fetal anemia is not expected if below 1: 64. Serial estimation of antibodies level every 2 weeks using titre (ICT) or autoanalyser is recommended.severe fetal anemia is not expected if antiD <4iu/ml by autoanalyser & is rare if < 10-15 iu/ml. There is possibility that the baby is RH –ve if father is heterozygous. PCR to test paternal zygozity is helpful as if father is homozygous the baby definitely RH+ &further management is planned. However this is not helpful if there is a problem with father identification. Fetal RH can be determined using non invasive cell free fetal DNA in maternal serum with accuracy of 96% .I will repeat test if baby RH –ve for assurance. Fetal RH can be determined by invasive testing chorionic villous sampling & amniocentesis but these carry risk of fetal loss , fetomaternal hemorrhage & further stimulation of antibodies production Doppler study of middle cerebral artery is indicated to detect fetal anemia .It is non invasive & reliable technique. should be done every 2weeks.Fetal hydrops is late sign & associated with poor prognosis, moreover not all cases of severe fetal anemia presented by hydrops. Other ultrasound markers such as amniotic fluid volume , placental thickness fetal movements are not proven to be beneficial. CTG for sinusoidal pattern is very rare & many cases of severe fetal affection don't show sinusoidal CTG, so it is not reliable for fetal assessment. Amniocentesis and estimation of bilirubin level plotted over Liyles chart & fetal blood sampling once optical desity reaches zone 3.It is invasive monitoring &uses bilirubin as indirect method of fetal heamoglobin estimation with lack of data about its timing & frequency .It carries 1% risk of fetal loss over background per procedoure. Cordocentesis allows direct estimation of fetal heamoglobin & heamatocrit, however it is invasive has 2% risk of fetal loss over background per procedure. B) Antenatal management of fetal anemia 2ry to RH should be in tertiary centre (fetal medicine unit) with available expertise & facilities for fetal monitoring & blood trasfution. Multidisciplinary team is needed (fetal medicine specialist, senior obstetrician, neonatologist,counseller) I know that psychological support for the woman & her partner in needed to alleviate anxiety associated with the condition & the need for sensitive approach. Cordocentesis is indicated to estimate hematocrite which if < 30 fetal blood transfution is indicated by packed o-ve RBCs compatible with both fetus &mother. It carries fetal loss rate of 2-4% per procedure.It is repeated /2-4 weeks till 34 week where consideration of delivery at 36 weeks is considered safer than continuing transfution. Maternal plasmapharesis &IV immunoglobulin injections to reduce antibodies are of limited efficacy. If fetal anemia is mild & the baby did not need intrauterine transfution plan delivery at 37-38week. |
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answer rhesus disease |
Posted by MONA V. |
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a) a.) Detailed obstetric history is taken regarding previous affected pregnancies. Previous baby with hydrops , intrauterine transfusions, neonatal anaemia asked as severity of disease increases with parity. Number of living children, mode of delivery noted. Ask with discretion of partner change as if father of this pregnancy is rhesusD negative fetus will be D negative and not affected. If father is Rh positive, zygosity is determined . If father is homozygous ,fetus will be rh D positive and at risk of haemolytic disease. If father is heterozygous , fetal rh status can be determined by free fetal DNA using maternal plasma.If negative repeat testing advised. Review level of antibody as passive anti D level <1mu/l can be due to recent RAADP routine anti d prophylaxis detected upto 8 weeks. Ask for recent blood transfusion, sensitising events. Anti D level < 4 Mu/L not associated with severe fetal haemolytic disease and repeat test in two weeks. Level 4 – 15 mu/L associated with moderate anaemia and > 15 mu/L with severe anemia. Further assessment done by middle cerebral artery MCA-PSV Doppler study in liason with Fetal medicine centre. Doppler of peak systolic velocity measurement of middle cerebral artery is best non invasive method to assess fetal anemia. Repeat Doppler done once on 1-2 weeks as per unit protocol and findings. USG evidence of hydrops pleural effusions, fetal ascites would need urgent referral and assessment in fetal medicine centre. CTG is not sensitive for monitoring, sinusoidal pattern due to severe anemia is late finding. Multidisciplinary team (MDT) comprising consultant obstetrician, senior midwife, neonatologist, fetal medicine specialist should assess fetus at risk of anemia and further management. Invasive test like amniocentesis for spectrophotometric analysis of amniotic fluid for bilirubin levels is an indirect measure of Hb and not done routinely nowadays. Liley graph plotted and zone 3 would indicate severe anaemia. MCA-PSV> 1.5MOM would require urgent referral to fetal medicine unit for intra uterine transfusion (IUT). Fetal blood sampling using cordocentesis for HB levels carries fetal loss rate of 2-4%
b) Fetal anaemia need management in fetal medicine unit by MDT comprising senior obstetrician, fetal medicine specialist, neonatologist. The woman and her partner are counselled about the procedure of codocentesis, need for repeated intrauterine transfusions and need for early delivery. Fetal loss rate of 2-4%, higher if hydrops is explained. Cordocentesis done , Hb hematocrit, bilirubin, blood group type done. If hematocrit < 30 IUT done . O negative blood cross matched with mother and fetal blod transfused. Aim to achieve supranormal Hb levels so frequency of IUT is 2-4 weeks. Monitor with weekly MCA-PSV. Antenatal steroids offered as risk of preterm delivery .,Couseling by neonatologist done. Individualise plan for labour depending on fetal anemia, development of hydrops. Deliver by 37 weeks . Aim for vaginal delivery , caesarean for obstetric indications. In case multiple transfusions , doppler changes plan to deliver after 34 weeks by caesarean after senior review. Provide written information |
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Essay 280 - Rhesus disease |
Posted by IE M. |
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A) History of the previous pregnancy should be taken to now if there is complication due to rhesus incompatibility, like hydrops fetalis, still birth or IUFD. Revise The record of the current pregnancy asking about the father is he the father previous pregnancy which mean that sensitization may happened in previous pregnancy and could affect this fetus. Asking about ante partum haemorrhage and if anti D was taken or not. Revising US scan report to see if IUGR or hydrops have occurred or not. Inquire about the fetal movement which can indicate fetal viability. Examine the mother to see the fundal hight and symphsio fundal measurement to see if there is polyhydramnios or IUGR. Fetal heart sound by Doppler checked to exclude IUFD. Blood group and RH of the mother and father should be done if not already known. If father is RH positive heterogenicity must be known. Anti bodies repeated two weeks later to know if there is increase or not. Investigation to know the fetal well being, either non invasive like US scan to see if hydrops fetalis develop. Middle cerebral artery peak velocity (MCA PV) to know if anaemia develop but it depend on examiner and the machine although it have high sensitivity. biophysical profile is important to know the well being. Invasive procedures like amniocentesis to do optical density 450 (OD450) against lilys chart. and bilurubin measure, but it carries risk of miscarriage 1-2 %. Fetal blood sampling by cordocentesis to check for HB if babies is anaemic or not, also blood group can be known, but it have a risk of still birth and miscarriage. Free DNA to know the blood group is a sensitive test. B) the aim of ante natal management is to know the severity of the disease so regular monitoring by weekly biophysical profile will reflect fetal condition, weekly MCA PV to know anemia, amniocentesis repeated for billrubin measure and OD450 . regular cordocentesis for blood sampling, growth scan every two weeks to monitor the growth. CTG could reflect the acute fetal compromise and may be helpful. Treatment depend on the gestational age, severity of the condition, and facilities available so treatment should be done in tertiary fetal unit. If gestational age less than 32 weeks corticosteroid 2 doses given. if severe anaemia intra uterine blood transfusion given, it need fetal unit and experience person and it carries the risk of preterm labour, PPROM. If gestational age near term after 32 weeks, deliver the baby and transfuse outside but also it depend on neonatal facilities. If condition of the fetus is stable and all investigation are normal delivery after 34 week. Psychological support to parent is very important throughout and information must be given backed with leaflet informaions |
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Rhesus Disease Essay Answer |
Posted by Axie P. |
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Consultant obstetrician with a special interest in Rh negative/immunised pregnancies should be involved in the management of the case.The management would depend on whether this is the first affected pregnancy or not. A detailed history must be sought such as the outcomes of the previous two pregnancies,history of any hydrops,need of in-utero blood transfusions,gestational age at which transfusions were needed,neonatal exchange transfusions,prolonged jaundice,etc should be asked.Present antenatal history in terms of booking antibody status,history of any vaginal bleeding,need of Anti D antenatally,h/o any invasive procedures,h/o trauma,etc should be asked.History of whether paternal zygosity has been performed should be noted. If this is the first pregnancy with anti-D positive status,in addition to the routine investigations done at 28 weeks,the antibody titres/quantification should be measured.If the levels are >10-15 IU/l,a referral to the Fetal Medicine unit should be sought.If the levels are <10-15 Iu/L,serial monitoring of these values(1-2 weekly) may be done to check if the critical values are reached. If this is not the first affected pregnancy,a Fetal Medicine referral should be considered for monitoring of the MCA-PSV values every 1-2 weeklyand to look out for signs of fetal anemia. After referral to the Fetal Medicine Unit,if the MCA levels reach >1.5 Moms ,significant fetal anaemia (false positive rate of 12%) should be considered and the parents counselled regarding the need of in-utero blood transfusion versus preterm delivery requiring neonatal transfusions.The parents should be counselled that the fetuses tolerate the transfusions better than the neonates.The risks of preterm delivery,PPROM,infections and fetal loss(2-4%) should be explained.The rh sensitised pregnancy may be continued with Intrauterine transfusions till 35-36 weeks after which delivery could be considered.The mode of delivery would depend on other obstetric indications. b)The parents should be sensitively counselled regarding the development of fetal anaemia by the Fetal Medicine Specialist and the consultant obstetrician. The ultrasound should specifiaclly look out for the signs of fetal anaemia such as ascitis,subcutaneous edema,pleural/pericardial effusion.The parents must be explained about the need for in-utero blood transfusion.Blood transfusion of O rh negative gamma irradiated,leucocyte poor blood would be given,usually intravascularly by cordocentesis or intrahepatic or if inaccesible,peritoneally.After explaiining the risks of preterm delivery,PPROM,infections and fetal loss(2-4%),If the parents consent,O negative blood (calculated volume) to raise the fetal hematocrit to 40%(non hydropic),25%(if hydropic) should be considered.Post transfusion Hb noted.The need for second transfusion will depend on MCA -PSv levels.If the pregnancy reaches 35-36 weeks and transfusions are still considered risks of a fetal loos vs preterm delivery should be considered. At delivery,the consultant neonatologist should be informed. |
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essay rhesus disease |
Posted by sowba B. |
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A detailed obstetric history must be asked from the woman to know if she was sensitised and was there any fetal hydrops .Any h/o intrauterine transfusions should be asked to know the severity of affection and the fetal outcome must be noted.Any sensitising event in the current pregnancy like chorion villus sampling ,amniocentesis,trauma causing fetomaternal bleed must be asked.It should be asked in a very sensitive manner if the current pregnancy was with a new partner as that may influence the outcome by a change in fetal blood group.The womans antibody titre must be looked into as the critical titre to cause haemolytic disease of newborn is taken as 1:32. Quantification of the actual antibody levels by an autoanalyser is more accurate than this and 1:32 corresponds to a value of 4iu/ml. this causes mild haemolytic disease,4-15iu/ml moderate disease and a value >15iu/ml causes severe affection. If the woman had got anti D recently as per the RAADP ,it can result in low antibody titres of 1iu/ml not significant to affect the fetus.
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Rhesus disease essay |
Posted by shazard S. |
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A) Recognize that a history of previous pregnancy outcomes is a poor predictor for gestation of onset and severity of rhesus disease in the index pregnancy. Maternal serum for fetal blood grouping (using free fetal DNA) should be done if available. If the fetus is Rhesus negative the fetus is not at risk for rhesus disease. If Rhesus positive the fetus is at risk for Rhesus disease. Maternal serum anti-D antibodies should be measured by IDCT or an auto-analyser serially(every 2-4weeks) as the risk of fetal anaemia is minimal at values less than 1:64.Peak systolic velocimetry using doppler scans of the fetal middle cerebral artery is a non-invasive screening tool for fetal anaemia. Consider its use if maternal anti-D levels are above 1:64. If elevated referral should be to a fetal medicine center for cordocenthesis. Cordocenthtesis allows direct measurement of fetal Haemoglobin concentration, blood group and bilirubin levels. It also allows for fetal karyotyping with parental consent. Cordocenthesis enables fetal blood transfusion if the fetal haematocrit is <30%. Cordocenthesis has a fetal loss of 1-2% and risks increased maternal antibody production with significant feto-maternal haemorrhage. Amniocenthesis with spectrophotometry of liquor for optical density is an indirect invasive measure of fetal haemoglobin with a 1% risk of fetal loss and is not recommended. Ultrasound scanning for fetal hydrops is a late inconsistent sign and is not recommended. Ultrasound scanning for liver length and dilated fetal veins is a poor predictor of fetal anaemia and is not recommended. Monitoring of Biophysical profile, fetal movements and CTG’s are poor indicators of fetal anaemia and are not recommended. B) Refer to a fetal medicine center for urgent review. Administer steroids to accelerate fetal lung maturity. Cordocenthesis should be done by a fetomedicine specialist to determine the fetal haemoglobin concentration, haematocrit and bilirubin levels. If the haematocrit is <30% a fetal blood transfusion should be done with O negative blood cross mathched to both the fetal and maternal serum. Transfusion maybe trans-peritoneal or intra-vascular. Transfuse to supra-normal levels to maximize transfusion intervals. Counsel the mother that fetal transfusion has fetal loss rate is 2-4% and that the procedure may have to be done again if fetal anaemia re-occurs. Timing of delivery should be individualized. If fetal transfusion is required recommend delivery at 34 weeks. Consider delivery at 36-37 weeks with transfusion at 34 weeks in some cases. If transfusion not needed, recommend delivery at 37-38 weeks to avoid fetal respiratory morbidity. |
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Essay 280 - Rhesus disease |
Posted by A A. |
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Ans. I will review her notes , for antibody screen at booking visit . I will check results of serial antibody titer if done so far. Negative results earlier in pregnancy point towards recent sensitization. I will ask for history of any sensitizing event , like vaginal bleeding, abdominal trauma, invasive procedure ,like amniocnentesis and chorionic villous sampling. Any of these, or if she has received anti Rh immunoglobulin (Ig) for any event recently, can lead to raised antibody titer though level will be different depending on degree of exposure. I will ask about previous pregnancies, and any adverse outcome,like severe fetal anemia, hydrops, fetal death or hemolytic disease of newborn. Risk of alloimmunization and its consequences increases with parity. I will ask her, if she received adequate routine anti Rh D prophylaxis(RAADP) during previous pregnancies and deliveries, as it decreases risks in subsequent pregnancy). She will be sensitively asked about change of partner. Abdominal examination may reveal excessive liquor in case of a hydropic fetus. Test of paternal zygosity( by PCR on blood) is done to assess susceptibility of fetus. If father is homozygous for Rh D antigen, baby will be Rh positive and at risk of hemolysis. If heterozygous, fetal blood group can be checked by cell free fetal DNA (cff DNA) from maternal plasma, or by amniocentesis and PCR. Amniocentesis is invasive, and further increases the risk of fetomaternal haemorrhage(FMH). cff DNA is non invasive with 96.5% sensitivity. If negative, repeat testing will be done( more than 3 % risk of missing out Rh positive baby). Maternal antibody titer correlates with degree of hemolysis . Severe anemia is not expected with antibody level below 4 iuand it is rare below 10-15 iu. Doppler studies of peak systolic velocity of middle cerebral artery(MCA-(PSV)) is a noninvasive method , with 100 sensitivity and 12 % false positive rate for detection of fetal anemia and is now preferred modality if expertise available. Ultrasound detection of reduced fetal movements and hydrops on ultrasound scan are late manifestations and a significant number of severely anaemic fetuses have normal movements and no detectable hydrops . Other markers such as amniotic fluid volume, placental thickness, umbilical vein diameter and liver length have not been shown to be useful. CTG is not of much value in assessment of anemia - sinusoidal pattern is rare, even in severe fetal anaemia. b) Antenatal management of fetal anemia should be done in a tertiary centre in liason with fetal medicine center and the method used should reflect the facilities available and expertise .Multidicsiplinary team should comprise of consultant obsterician , fetal medicine speciaist, and specialist midwife.Couple will be counseled about the procedures and risks involved and informed consent will be taken. Maternal antibody titer will be checked two weekly. Doppler studies should be done weekly. Antibody titer more than 15 iu, or PSV of MCA more than 1.5 Multiples of median for given gestation, is thresh hold for moderate to severe anemia, and fetal blood sampling and transfusion. Amniocentesis and spectophotometry to estimate bilirubin levels (OD450) can be plotted on Liley’s chart, with fetal blood sampling once zone 3 is reached. Cordocentesis for FBS, has a fetal loss rate of 1-2% per procedure. Both procedures carry a risk of FMH and increased maternal antibody levels. Intrauterine blood transfusion is done when haematocrit is below 30%, using packed O Rh negative red cells compatible with both the mother and fetus. Transfusion will be done to supranormal Hb concentration, with longer interval between transfusions (2-4 weeks). It carries risk of infection, haemorrhage, fetal bradycardia, cord haematoma, tamponade; and fetal death .Procedure-related fetal loss rate is 2-4%. Intra-vascular route is preferred to intra-peritoneal route. Delivery after 34 weeks gestation may be considered safer than continued intra-uterine transfusion. Other treatments such as plasmapheresis and maternal intravenous immune globulin have limited efficacy. Last intravascular transfusion at 34 weeks (unless difficult or dangerous) with delivery at 37 weeks can be considered. |
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Posted by khalid M. |
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A] Take detail history of previous pregnancies and there fetal out come whether they recieved intra uterine transfusion , any still birth or neonatal death due to severe jaundice. ask the women whether she had taken anti d prophylaxis before and following any sensitising event or after child birth . ask if having recieved any recent dose of anti d prophylaxis as the antibodies titre tend to raise up to 8 weeks . ask the women if any recent history of abdominal trauma, vaginal bleeding that could have resulted in FMH and raise in antibody titre . counsel the women that the severity of the disease raises with increasing parity . Refer the patient to fetal medicine unit where there are facilities to manage rhesus iso immunisation . screen the partners blood group and genotype . if he is homozygous almost all the fetus are affected . if he is heterozygous then 50% of the fetus will be affected .review her antenatal notes to detect the booking antibody level and the recent antibody level by indirect coombs test . if the level was below 4 IU then there is no fear of the fetus being affected .monitor the fetus by checking the antibody level every 2 weeks ,if more than 10-15 IU there is risk of the fetus being affected .do invasive and non invasive method of fetal monitoring .if the antibody titre is raised , early intervension and prompt treatment can be given .non invasive method such as CFFDNA for fetal blood group and RH status in maternal blood is done . it has a high sensitivity . if the fetus is rh negative then repeat it after confirmation reassure the patient . Invasive method of fetal monitoring such as amniocentesis is done . fetal blood group and rh status is done check antibody level if >10 -15 iu then do sphectrometry OD 450 to estimate bilirubin level in fetus and plot on lilleys chart . this is indirect method of estimating fetal HB level after 28 weeks of gestation . level 3 indicates severe anemia . amniocentesis is associated with 1% risk of miscarriage and allo immunisation .then do fetal blood sampling for haemoglobulin level, haematocrit level ,reticulocyte count .if haematocrit level is <30% the fetus is having anemia and needs intrauterine transfusion .Usg is done to see for the signs of hydrops and this is repeated every 2 weeks . doppler studies is done to assess the amount of blood flow in the middle cerebral artery increased flow suggest fetal anemia . and the peak systolic velocity is measured if it is > 1.5 mom then the fetus is anemic . CTG is done ,sinusoidal pattern and decceleration suggest fetus at risk of anemia .but it has poor predictor value .
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Posted by Nana B. |
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Ans
a.I will confirm fetal viability via a history of normal fetal movements and auscultation of fetal heartbeat with sonicaid. I will arrange her routine FBC,Blood group and screen for antibodies eg antibodies to c, E, K antigens which can also cause fetal and neonatal anaemia.
I will take a history of past HDFN, and blood transfusion to assess the possible source of antibodies, as disease due to blood transfusion is less likely to be severe than fetomaternal haemorrhage.
I will offer paternal rhesus status testing after excluding uncertainty about paternity . If the father is rhesus negative I will reassure her that the fetus will be rhesus negative and not at risk of rhesus disease . If he is rhesus positive I will test for zigosity.
If he is homozygous the fetus is rhesus positive ,but if he is heterozygous the baby has a 1 in 2 chance of being rhesus positive .
I will offer Cell free fetal fetal DNA in heterozygous father, uncertain or unknown paternity. This has an accuracy of 95% or more in identifying fetal rhesus status .
If the fetus is found to be rhesus negative I will reassure her of the absence of risk of rhesus disease .
In all cases of rhesus positive fetus I will arrange monthly antibody titre .If the antibody level reaches 1:32 or higher I will refer to a regional fetal medicine center for counseling and monitoring for fetal anaemia.
Fetal anemia may be monitored using weekly dopplers of the middle cerebral artery (MCA). MCA peak systolic velocity (PSV) greater than 1.5 multiples of the median for gestation is diagnostic of fetal anaemia, with a sensitivity of 100% , and a 12% False positive rateThis is a non-invasive test with high sensitivity and minimal fetal and maternal risk .
. Significant Fetal anaemia is an indication for invasive testing by FBS And intrauterine transfusion , or delivery and neonatal transfusion .
The alternative to fetal MCA Doppler is 1-4 weekly amniocentesis with assessment of amniotic fluid spectrophotometry at 450nm. The results are plotted on Liley’s graph. Anaemia is signified by readings in zone 3,or rising in the upper third of zone 2.
This is invasive and carries a risk of infection ,preterm delivery , PPROM, and worsening fetomaternal haemorrhage
b.
I wil explain the diagnosis to her sensitively and explain the high risk of fetal hydrops and fetal death in untreated cases . I will explain that prognosis is improved with specialist care , fetal surveillance, intrauterine transfusion and planned delivery followed by specialist care by neonatal care team, including testing for anaemia, hyperbilirubinaemia, blood transfusion and phototherapy . I will provide written information on HDFN. I will warn her of the small risk of perinatal death with FBS and fetal transfusion .
There will be no further need for anti-D in this or future pregnancies.
I will offer her referral to a regional fetal medicine center. Here she will receive Doppler of the MCA and if anaemia is confirmed intrauterine transfusion will be offered ,after FBS confirmed anaemia. Blood for fetal transfusion will be crossmatched against maternal blood and should be rhesus negative .
She will continue weekly dopplers of fetal MCA with serial growth scans 2weeky to monitor fetal growth .
In the absence of further evidence of anaemia, planned delivery after 37weeks, after close liaison with the neonatal unit ls recommended . Vaginal delivery is appropriate and IOL can performed. Intrapartum fetal monitoring is advisable due to the ongoing risk of fetal anaemia.
Caesarean section may be needed for obstetric indication or maternal request .
If there is MCA evidence of fetal anaemia after 35weeks I will advise delivery ,usually by C/S, after steroid prophylaxis .
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