404 SPO Abstracts

468 FETAL LUNG ~ATURITY TESTING PROTOCOL: SURFACTANT/ALBUMIN RATIO. L.A. Bayer­Zwirello, B.A. Morris*, C.M. Kanaan, M.L. Gimovsky, J.P. O'Grady. Dept. of Ob/Gyn, Baystate Medical Center, Springfield, MA

An automated amniotic fluid surfactant­albumin ratio test (SAR) was performed for lung maturity on 137 pregnancies delivered within -;3 days. 20/137 (15.6%) of neonates developed respiratory distress syndrome (RDS); 6/37 (4.9%) had transient tachypnea (TTN); the remaining 111/137 (78.8%) were clinically normal. The SAR had a sensitivity of 96.0%, a specificity of 75%; positive predictive value 46.1%; negative predictive value of 98.7%; interassay coefficient of variability 3.5%. Conclusion: The SAR for lung maturity is automated, rapid (~1 hr), inexpensive, precise, and uses ~ 1 cc fluid. Our protocol uses the SAR as our initial, rapid screening test for fetal lung maturity. The L/S ratio follows the SAR only if the initial study is immature. This protocol has reduced the number of L/S ratios required in our high risk population while retaining clinical accuracy and reducing cost.

469 NONFRANK BREECH PRESENTATION: EFFECT OF MANAGE­MENT ON OUTCOME. D. Gauthier,x S. Warsof. University of Illinois at Chicago, Chicago, IL.

Nonfrank(NF) breech presentation is consid­ered by many as an indication for C-section(CS~ The purpose of this study was to assess the ef­fect of intrapartum management on neonatal out­come. METHODS. Retrospective analysis of sin­gleton NF breech deliveries >34 weeks EGA dur­ing a 10 year period was performed. Different managment plans included selective vaginal de­livery(SVD) in which route of delivery was de­termined after evaluation of fetal weight, head position, and maternal pelvis, unselected vagi­nal delivery(UVD), elective CS for NF breech (ECS), and CS for other indication(OCS). RESULTS. Neonatal outcome for 290 NF deliveries is summarized as follows: MANAGEMENT SVD UVD ECS OCS

NUMBER 5" APGAR <7 BIRTH TRAUMA MORTALITY

VD 86 5(2)

1 2(0)

CS-NTOL CS-TOL -5-3-- --1-4-

o 1 (0) 2 0 o 1 (0)

24 5(2)

1 2(0)

95 6(2)

2 2(0)

VD=Vaginal delivery, CS-NTOL=CS-no trial of labor, CS-TOL=CS after trial of labor,

18 2(0) o

2(0)

( )= corrected for congenital anomalies. CONCLUSIONS: (1) THERE WAS NO DIFFERENCE IN NEO­NATAL OUTCOME IN SVD VERSUS ECS, (2) CONGENITAL ANOMALIES WERE THE LEADING CAUSE OF MORTALITY.

January 1992 Am J Obstet Gynecol

470 ANTEPARTUM MANAGEMENT OF TRIPLET GESTATIONS. AM Pe8Ceman, SL Dooley, RK Tamura, ML Socol. Department of Obstetrics and Gynecology, Northwestern University Medical School, Chicago, II.

Recent improvement in perinatal outcome for triplet gestations has been attributed to the use of routine antepartum hospitalization, home uterine contraction mon~oring, tocolytic therapy, and cervical cerclage, but the value of these interventions has yet to be established. Furthermore, published series continue to report preterm delivery rates of 82-1 00%. We evaluated an alternative approach to the management of triplet gestations to determine its efficacy in the early diagnosis of preterm labor (PTL) and reduction of preterm birth. This approach included patient education regarding signs and symptoms of PTL, weekly prenatal visits with cervical examination after 24 weeks' gestation, and ina-eased rest in an outpatient setting. Tocolytic therapy was restricted to gestations < 34 weeks in which progressive cervical change was documented in association with uterine contractions. Fifteen patients with triplet gestations were managed by this protocol over a 3 year period. Ten patients were hospitalized in the antepartum period forthe following indications: PTL (4), advancing cervical dilation or effacement without contractions (5), and preeclampsia (1). Five patients received tocolytic therapy with MgSO" as one patient hospitalized for cervical dilation subsequenUy developed PTL; the interval from tocolysis to delivery was 37 ± 15 days (range 27-63). No patient was delivered because of failure to detect PTL in sufficient time to initiate successful tocolysis. The mean gestational age at delivery was 34.7 ± 2.6 weeks; 10 of 15 (67%) patients achieved 34 completed weeks' of gestation, and 6 (40%) completed 37 weeks. Indications for preterm delivery included labor at;;, 34 weeks (4), premature rupture of membranes followed by labor (3), suspected placental abruption (1), and worsening preeclampsia (1). Mean birth weight was 1957 ± 488 grams, and 29 of 45 (64%) neonates did not require admission to the intensive care nursery. One neonatal death occurred secondary to nea-otizing enterocolitis. We conclude that this management scheme for triplet gestations allowed for appropriate recognition of preterm labor and was as successful as protocols utilizing more expensive or invasive technologies in reducing the preterm delivery rate.

471 INCIDENCE OF MATURE LIS RATIO IN THE PRESENCE OF AN IMMATURE FOAM STABILITY INDEX (FSI).Asrat

L Towers CV, Lewis DL, Ogburn AX, Nageotte MP, Women's Memorial Hospital, Long Beach, CA, University of California. Irvine,CA.

A commonly employed scheme of ascertaining fetal pulmonary maturity involves the use of the "maturity cascade" which consists of the "shake" test, followed by the FSI and fmally the Lecithin Sphingomyelin (LIS) ratio if the frrst two tests indicate pulmonary immaturity. We conducted this study in order to determine the distribution of LIS values following an immature FSI, across various gestational ages. An immature FSI is defined as $.0.46. From 1/86 to 12/89 857 samples of amniotic fluid were evaluated by an FSI. 259 of these samples had an FSI of <0.46 and 136 had an FSI equal to 0.46.

GA<Wks) 28-29 29-30 30-31 31-32 32-33 33-34 34-35 35-36 36-37

N 4 7 12 25 4'i 36 :R 42 29

%Mature LiS (No.of FS1<0.46

0%(0) 0%(0) 0%(0) 0%(0)

4.4%(2) 8.3%(3) 8.4%(5) 7.1%(3)

31.0%(9)

Samples) N FSI 0.46 I 0%(0) 2 0%(0) 4 0%(0) 8 12.5%(1) 18 55%(1) if, 30.7%(8) 32 28.7%(9) 24 46Jl%(II) 21 62.0%(13)

%Mature LIS (95% CI) GArWks) FS1<0.46 FSI-0.46 Total <32 0/48 1/15 1/63-1.6%(0-4.6) ;::32 22/211 42/121 64/33219.2%(15.0-23.5) CONCLUSION: The above data indicate that at gestational ages below 32 weeks, if the FSI is $.0.46 there appears to be no need to move on to an LIS. Furthermore, between 32 and 35 completed weeks, if the FSI is only <0.46 the rate of a mature LIS is less than 10%, and the routine assay for LIS may not be cost effective.