Volume 16~ Number 1. Part 2

336 FETAL EXSANGUINATION FOLLOWING UMBILICAL CORD BLOOD SAMPLING Daniel A. Rightmire, M.D. and Ernest E. Ertmoed, M.D.X Southern Illinois University School of Medicine, Springfield, IL

Pregnant women with anti-platelet antibodies are advised to have fetal blood sampling prior to delivery to estimate the risk of fetal hem­orrhage. Fetal exsanguination from umbilical cord blood sampling has not been reported from fetal thrombocytopenia. We present a case of fetal exsanguination from an otherwise uncomp­licated fetal cord blood sampling at 21t weeks gestation associated with maternal alloimmuni­zation to PLA1 antigen. The 30-year-old white woman, G6, P0231, had become pregnant in anti­cipation of treatment with IV gamma globulin. She had delivered a 35-week gestation, compli­cated by fetal thrombocytopenia and extensive intracerebral hemorrhages. Family histories were negative for bleeding disorders or throm­bocytopenia. The patient avoided drugs, chemi­cals and viral illnesses. Removal of the 20-gauge, Teflon-coated needle from the cord re­sulted in 17 minutes of visible fetal hemorr­hage. The fetal hemoglobin concentration was 7.4 gm/dl with an hematocrit of 22.5% and a platelet count of 5,OOO/cu mm. At autopsy there was no evidence of fetal internal bleed­ing and no gross evidence of a cord lesion.

337 TRANSVAGINAL MULTI FETAL REDUCTION: OPTIMAL TIMING AND TECHNIQUE Ilan E. Timor-Tritsch. Ana Monteagudo, David B. Peisner. Department of Obstetri cs & Gynecology, Sloane HOSPl ta 1 for Women, Co 1 umbi a Presbyteri an Medl ca 1 Center, NY, NY .

After the ethical problems of multifetal reduction (MFR) were settled and its benefit established at least two questions still remain unanswered. a.When should the procedure be performed to avoid the reduction of a normal fetus and allow the continuatl0n of a structurally abnormal one? Thi s quest i on was prompted by the detection of two anomalies seen, weeks after the reductions. b.Whether the manual, or an automated needle puncture technique wi 11 mi nimi ze the comol i catlOns? Thl s quest i on was ral sed after observing a difference in campI ications and losses after i ntroducl ng a spri ng loaded puncture devi ce. Fi fty three transvaginal MFRs were done in 52 patlents. The mean gestational age and mode at reduct i on was 9 week 0 days (range of 6 weeks 2 days to 15 weeks). Free hand needle puncture (group A) was done ln 40 cases (reduclng from 141 to 73 fetuses). In almost all cases requl ri ng reduct i on of 2 or more fetuses the needl e was repositi oned several t 1 mes without its total extractlon from the uterus. In the last 13 reductions (group B) a spnng loaded device (Labotect, Gottingen FRG) was used (reducing from 49 to 26 fetuses). The needle was introduced anew for each fetus to be injected. Two meq/ml KCL solution was used. The results showed that in one case in whi ch the reductlOn was done at 8 weeks 2 days (3 to 1) a thick nuchal fold necessitated chromosomal work-up In a second case done at 9 weeks (3 to 2) one of the tWl ns had a cephalocele requiring a second 2-1 reduction at 12 weeks. In group A the comp 11 cat ions included: 5 subchori ani c hematomas, 3 procedure related losses (9 wks from reductl0n) and 3 late losses. In group B no subchori oni c hematoma or losses occurred. Due to the small numbers the di fference di d not reach stat i st i ca 1 si gni fi cance. Conclusion: To assure a better outcome and less c~l ications of MFRs: a. fetal reduction should be perfonned at or after 9.5 weeks, after high resolution transvaginal sonographic structural evaluation of the fetuses; b. The spring loaded automated vaginal puncture devi ce SeEIIIS to I ead to better results.

SPO Abstracts 339

338 LIVER-CONTAINING VS NON-LIVER-CONTAINING OMPHALOCELE. TIMING FOR TRANSVAGINAL SONOGRAPHIC DIAGNOSIS OF TWO, POSSIBLY DIFFERENT ENTITIES. 11 an E. Timor-Tri tsch, Ana Monteagudo, and Shraga Rottem' Departments of Obstetrlcs & Gynecology, of the Sloane Hospltal for Women, Columbia Presbytenan Medical Center, NY, NY and Rambam Medical Center, Haifa, Israel.

We reported earl ier on the accurate detectlOn of mldgut herniation (MH) by transvaginal sonography. The bowel ln early pregnancy appea'rs as a hyperechoi c structure. Thl s sonographl c property can be used to locate the bowel Wl thl n the cord from 8-12 weeks (phYS1010glC mldgut hermatlOn) or within the abdomlnal cavity after 12 weeks. Classically ln a well dated pregnancy an omphalocele can be dlagnosed after 12 weeks if the area of the cord lnsertion, which should appear normal at this gestatl0nal age, contalns a protruding structure. The echogeniclty of the 11Ver and the bowel 1 s different startl ng the 9th week. The l,ver early ln gestatlOn assumes its charactenstlc homogeneous lower 1 eve I-echo pattern for whi ch it 1 S recogm zed wherever it may be. The l,ver does not follow a phYSl010glC mlgratlOn outslde the abdomen, in contrast to bowel, as part of the embryo 1 Ogl ca 1 development. The issue of the ectopl c 11 ver was ra i sed at the time of chori om c vl11 us samp 11 ng 1 n a fetus at 9 weeks. At th,S time an extraabdomlnal, paraumbilical structure matchl ng the well known echogeni ci ty of the 1 i ver was observed. The chromosomal study was normal. A follow-up scan at 14 weeks reconfi rmed the presence of a large ventral wall defect, contai ni ng the 1 i ver, covered by peri toneum. Our conc 1 USlOn therefore 1 s that regardl ess of the gestat lOna 1 age 1 f 11 ver tissue lS seen outside the anterior abdominal wall, th,s should be regarded grossly abnormal. Omphaloceles contaimnq l,ver may be a dlfferent dlagnostic entity (usually not assoclated wlth chromosomal abnormalltles) and can be made before 12 weeks. ThlS in contrasts to the non-l i ver contalm ng ompha 1 oce 1 es whi ch can be dlagnosed only after 12 weeks and have a higher assoclatlOn with chromosomal abnormalities.

339 FACTORS WHICH INFLUENCE IMAGING OF THE FETAL HEART DURING THE SECOND TRIMESTER OF PREGNANCY Greggorv R. DeVore. M D., Arnold MedeariS, M.D., Moraye Bear MS.,' and Lawrence D Platt, M.D,; Salt Lake City, UT and Los Angeles, CA

In 1988 the American College of Obstetricians and Gynecologists recommended the four -chamber view of the fetal heart be imaged during the basic ultrasound examination of the fetus Because of the medical­legal implications of failed diagnosis of congenital malformations during the second trimester of pregnancy, this study was undertaken to Identify factors which influenced the ability to Image the fetal heart Seven hundred and thirteen (n=713) fetuses were studied between the 15 and 22 weeks of gestation. All examinations were pprformed by the same examiner (GRD), Ultrasound examination consisted of measurements of the head, abdomen, and femur; evaluation for structural malformations; and examination of the fetal heart which included the four -chamber and outflow tract views. The cardiovascular examination was coded as adequate or inadequate for exclusion of structural malformations. The following factors were evaluated by linear logistic regression analysis to determine their influence on imaging of the fetal heart: maternal height and weight, adipose thickness at the site of imaging (AT), distance from the skin to the heart, histOlY of previous pelviC surgery (S), and gestational age (GA) The above quantifiable factors were analyzed as measured (I.e. AT) and squared (i.e AT2 ). Of the 713 fetuses studied, 907% (n=647) demonstrated adequate Imaging of the heart Linear logistic regression iden@edthefollowing as significant (p<O.OOOI) factors from which the probability of imaging the fetal heart could be computed' GA, AT,AT2,and S. For example, the probability of imaging the fetal heart at 16 weeks with no surgery and an AT of 2 cm Is 97.6% which decreases to 14 % with an AT of 3.2 cm. When surgery is positive, the probability decreases to 55% and < 1 %, respectively. F rom these data, the physician can quantitate the probability of successfully imaging the fetal heart for a given AT and history of surgery and determine the optimal gestational age during the second trimester for imaging of cardiac structures