The Seoul Jollrnal oJ',2.ledicine vol. 34, No. 3 195-205,September 199.3

Preliminary Experience of

Woo Jin Kim, Bo Hyun Yoon, Sook Hyun Ki, Me Lee Lee, Jong Kwan Jeon, Hee Chul Syn and Syng Wook Kim

Department of and Gynecology, Seoul National University College of Medicine, Seoul 110-744, Korea

= A bst ract = is considered as one of the major obstetrical dilem- mas for the multiple serious complications associated with the condition. The condition hampers an appropriate ultrasonographic evaluation of the fetal anato- my and frequently causes variable fetal heart rate decelerations by compressing the fetal cord, often to incur irreversible damage to the . Based on precedent reports regarding the effect of amnioinfusion in managing oligohydramnios-com- plicated , we report here our experience of amnioinfusion in 8 cases complicated by oligohydramnios which we have experienced from November of 1990 to May of 1993 at Seoul National University Hospital(SNUH). The proce- dure was applied largely for three purposes, viz., diagnostic(3cases), therapeutic (4cases), and prophylactic(1case) with favorable results. We concluded that amnioinfusion can be of important use in the detection of fetal anomalies, relief of abnormal fetal heart rate pattern, and prevention of intrapartum fetal compli- cations.

Key Wo rd s : Oligohydramnios, Fetal heart rate decelerations, Amnioinfision

right time. Complications associated with oligo- INTRODUCTION hydramnios are multiple, but two are well known. One is the predisposition to umbilical cord com- Oligohydramnios, etiologies of which consist pression which results in variable fetal heart rate of genitourinary tract obstruction, renal dysfunc- decelerations and another is its deleterious tion, premature rupture of membranes, fetal- effect on the development of fetal lungs to play a growth retardation, and more, is one of the major major role in causing oligohydramnios syndrome obstetrical perplexities as it usually forebodes or tetrad consisting of pulmonary hypoplasia, or poor fetal outcome and at the same time does orthopedic deformities, Potter's facies and fetal not allow good ultrasonographic evaluation of growth retardation(Strin9er et a/. 1990). the fetus to take appropriate measures at the For the aforementioned oligohydramnios- associated complications, the procedure of

Received July 1993, and In final form August 1993 amnioinfusion has the advantages of offering ~j4gqqzqi!+qq *qqi!+qyJg: %+-a,$9 diagnostic, therapeutic and further prophylactic 3,7143, 01014. a$g, 44%. %$% solutions. Amnioinfusion, which is the process of instilling fluid, usually normal saline, into the and 7), and prophylactic(case 8). amniotic cavity, enhances ultrasonographic visu- Methods of amnioinfusion: Routes of alization by providing an acoustic window for an amnioinfusion employed were either transab- improved resolution and freeing the fetus from dominal or transcervical. For the cases with rup- the flexed position incidental to oligohydramniot- ture of membranes the transcervical route was ic state; and also relieves variable fetal heart rate used. The basic infusion equipment consisted of decelerations by forming amniotic pockets intravenous extension tubing, a three-way stop- around the compressed cord and placenta, cock, and 1,000ml of normal saline solution thereby reducing cord and placental compres- warmed to 37" C with blood warmer. For the sion. Improved ultrasonographic visualization transabdominal route, 21 gauge spinal needle makes it possible to recognize any existing was employed for puncture and conduit. anatomical problem and makes differential diag- Throughout the infusion process, the mother was nosis possible for appropriate intervention where kept in the left lateral position with adequate oxy- needed. Relief of fetal heart rate decelerations gen supply via facial oxygen mask and constant could result in improvement in fetal metabolic monitoring of the uterine contraction and fetal state to allow labor to proceed without operative heart tone were made by external tocody- intervention. Reports of successful amnioinfusion namometer(1 15 Fetal Monitor, Corometrics have already been made by many groups after Medical System, inc). Whenever possible, the Miyazaki and Taylor(1983) who performed this infusion was maintained at a rate of 10 to 20ml procedure on humans for the first time. per minute and until the Thus far there have been no reports on reached a value of 8. Amniotic fluid index and amnioinfusion in Korea and here we report our biophysical profile were assessed according to experiences of amnioinfusion in 8 cases accu- the descriptions made by Manning et a1.(1980). mulated since 1990 where the procedure was Table 1 demonstrates the clinical characteristics performed for diagnostic, therapeutic and pro- and methods of amnioinfusion of the 8 cases. phylactic purposes. CASE REPORT MATERIAL AND METHODS CASE 1 Study Population: Amnioinfusions of this A 22-year-old woman, gravida 1, para 0 was report were performed from November of 1990 referred to our Department at 24+4 weeks of to May of 1993 on the patients diagnosed ultra- with oligohydramnios on November sonographically to have oligohydramnios 18, 1992. At the time of visit, amniotic fluid index defined to be the absence of at least one amnio- was 4.3 with both kidneys appearing normal. On tic fluid pocket measuring greater than 1 x Icm. November 30, the amniotic fluid index was fur- The gestational ages of the amnioinfused ther decreased to 3.7 and she was admitted. patients ranged from as early as 17 weeks to as Amnioinfusion of 500ml of normal saline was per- late as 42 weeks of gestation. formed transabdominally on the next day to bring up the amniotic fluid index to 7.7. The procedure was performed at the discre- Ultrasonographic follow up made on December tion of the attending doctor on a case by case 3rd showed absence of both kidneys and blad- basis and not according to any strict criteria, der but a cystic lesion measuring 1.2 to 1.5cm in after receiving an informed consent from the diameter was observed. On December 7th, patient and the family. The procedure was amniotic fluid index was measured at 3.0 and a employed largely for three purposes, viz., diag- second attempt at amnioinfusion was made to nostic(cases 1,2, and 3), therapeutic(cases 4,5,6 increase the amniotic fluid index to 10.0. However on a repeat sonographic assessment Table 1. Clinical characteristics and method of amnioinfusion of the 8 cases

Case Gestational Additional Method of infusion Post-infusion Fetal age at the pre-amnio outcome outcome diagnosis of infusion oligohydram- problems Amount Route No. of infusion nios

Diaanostic

1 25 Week (-1 500ml Transab- 2 Detection of 1.22kg,female, dominal polycystic kidney stillborn on the second trial terminated of amnioinfusion 2 22 Week (- 1 600ml Transab- 1 Detection of fetal 5409, male, dominal hydrocephalus stillborn and absence of terminated fetal heart tone

3 17 Week Huge 1st-560ml Transab- 1 Visualization of 290g, male, abdominal dominal both kidneys after stillborn cyst(USG) 2nd-300ml Transab- 1 cyst aspiration dominal Chorioamnionitis (probably due to infusion)

Therapeutic 4 34 Week FGR, low bio- 350ml Transab- 1 Improved 980g, male, physical profile' dominal variability and AS(5 to 6), score, late de- disappearance of premature celerations, decelerations spontaneous compromised cord vaginal blood gas status delivery

5 39 Week FGR, 250ml Transcer- 1 Reduction in 2.28kg, male, variable vical variable AS(9 to lo), decelerations decelerations spontaneous

6 39 Week Early 450ml Transcer- 1 Decreased fre- 2.09kg, female, decelerations vical quency of early AS(7 to 8), decelerations spontaneous vaginal delivery

7 42 Week Rupture of 500ml Transab- 1 Disappearance of 3.51kg, male, amniotic dominal decelerations, AS(3 to 6), membranes, improved vari- CIS due variable ability to dystocia decelerations Table 1. (Continued)

Case Gestational Additional Method of infusion Post-infusion Fetal age at the pre-amnio- outcome outcome diagnosis of infusion oligohydram- problems Amount Route No. of infusion nios

Prophvlactic 8 33 Week Premature 250ml Transcer- 1 Uneventful labor 1.95kg, male, rupture of vical course AS(7 to 8), membranes premature spontaneous vaginal delivery

FGR-Fetal growth retardation,USG - Ultrasonography, IVP - Intravenous pitocin, AS-Apgar score, CIS-Cesarean section on December 8th, the diagnosis of polycystic kid- ney with oligohydramnios and a subsequent deci- sion to terminate the pregnancy were made. On CASE 3 December 1lth, following the use of Nalador@,a A 25-year-old woman, primigravida was female infant weighing 1.22kg was stillborn. The referred to our unit on May 3rd,1993 with sus- patient was further managed and discharged pected short fetal extremity at 16+5 weeks of uneventfully. Subsequent autopsy findings pregnancy. revealed the fetus to have bilateral renal dyspla- As the ultrasonographic finding at the time sia (Potter type Ilc cystic disease) and hypopla- of the visit consisted of significantly decreased sia of the urinary bladder amniotic fluid(amniotic fluid index of less than 1) and a huge abdominal cyst measuring 7.5 x 7.9 CASE 2 x 7.0cm, she was admitted under the impres- A 29-year-old woman, gravida 2, para 1 was sion of fetal urethral obstruction. On the next day, referred to our Department on January 14th, the cyst was aspirated of 315ml to greatly 1993 at 21 +3 weeks of pregnancy with oligohy- reduce the size of the cyst to 1.6 x 1.1 x 1.2cm dramnios.Ultrasonographic examination then and amnioinfusion with 560ml of normal saline revealed the amniotic fluid index to be 0.8 with was performed to evaluate detailed anatomy. breech presentation and a low-lying placenta. The components of the aspirated fluid were simi- Two days later 600ml of normal saline was lar to urine. infused transabdominally into the amniotic A second trial of cyst aspiration for 40ml to cavity. Ultrasonography two hours following the further decrease the size of the cyst to 0.7 x 1.4 infusion showed an absent fetal heart beat and x 0.9cm and amnioinfusion with 300ml of nor- fetal hydrocephalus. mal saline were performed on May 7th. On the next day, laminaria was inserted for On 11th of May, fetal echocardiography termination and a male infant weighing 540g revealed the heart to be free of any significant was stillborn on January 28th.The infant was disease and the size of the cyst to be again grossly free but there was only a single artery, as increased to 5.6 x 4.1 x 4.5cm, a solution to opposed to the normal two arteries, and a vein in manage for which vesicoammiotic shunt tube the umbilical cord. insertion was suggested but the procedure could not be performed as premature rupture of Following the infusion, a dramatic improve- membrane accompanied by ultrasonographic ment in the variability of fetal heart rate as well diagnosis of absence of fetal heart movement as disappearance of deceleration were soon took place. Subsequent to the rupture of observed almost immediately as shown in Fig. 2 membrane, a male infant weighing 290g with and a vaginal prostaglandin suppository was abdominal distension as the only gross anomaly inserted into the posterior fornix of the vagina for was stillborn. as the fetus was considered to Autopsy findings were imperforate cloaca1 be in severe acidosis(Lucie et a/.1990), but late membrane with ureteral atresia(right), polycystic decelerations later showed up with contractions kidney (type IV) with ureteral atresia(left), and to consider an emergency cesarean delivery. acute suppurative chorioamnionitis of the pla- Unfortunately the guardian refused the proce- centa. dure and intravenous Yutopar was started to relieve the deceleration. Labor progressed and a CASE 4 980g male infant with an Apgar score of 5 to 6 A 26-year-old primigravida was referred on was delivered. The infant was then managed at November 13, 1990 to our Department from an neonatal intensive care unit with a sole complica- outside hospital at 33+3 weeks of pregnancy with tion of intraventricular hemorrhage(Gr.ll), but 11 oligohydramnios. days later the baby was taken home against According to the ultrasonographic examina- medical advice. tion, the fetus was severely growth retarded with an amniotic fluid index of 4.6. She was admitted CASE 5 on the next day and follow up of amniotic fluid A 35-year-old woman, gravida 6, para 0, index was made. The amniotic fluid index was was admitted on November 19,1990 at 38+4 further decreased to 3.2 on the admission day weeks of pregnancy with oligohydramnios, fetal and then to 1.5 on the day following. On the third growth retardation, gestational diabetes mellitus admission day, cordocentesis for rapid karyotyp- and hyperthyroidism. The ultrasonographic find- ing and cord blood acid-base and gas analysis ing prior to amnioinfusion consisted of a bio- due to severe intrauterine growth retardation and physical profile score of 8 out of total score of amnioinfusion for oligohydramnios were per- 10, amniotic fluid index of 4.8 and a fetal heart formed. Preceding the two procedures, the bio- rate of 145lmin without any decelerations. On physical profile of the fetus were: non-stress test November 21, during tococardiographic record- (0); fetal breathing movement (0); fetal move- ing, variable decelerations 'appeared and to ment (0); fetal tone (2); and amniotic fluid volume relieve the stress, 250ml of 37°C normal saline (0). During the non-stress test, late decelerations was infused intc the amniotic cavity first to cause with even a drop of fetal heart rate to below 50 reduced frequency of variable decelerations and beats per minute was observed and there was as there was no point delaying delivery,intra- almost no variability of fetal heart rate (Fig.1). venous pitocin induction was started to give The blood gas analysis of the umbilical venous vaginal birth to a male infant weighing 2.28kg blood obtained by cordocentesis were: pH (7. with an Apgar score of 9 to 10 on the same day. 23); PC02 (49 mmHg), PO2(36 mmHg), and Both the mother and infant were discharged fol- HC03(20mmol/l). The infusion made was 350ml lowing an uneventful hospital course of 37" C normal saline, Immediately following infusion, ultrasonographic findings were : amni- CASE 6 otic fluid index (8); non-stress test (unsatisfacto- A 28-year-old, nulligravida was admitted on ry); fetal breathing movement(1); fetal movement November 20, 1990 at 38+4 weeks of pregnancy (1); fetal tone(1); and amniotic fluid- volume(2). due to oligohydramnios and for induction of Fig. 1. Monotonous fetal heart rate pattern with severe late decelerations(as low as 45 beatslmin) is shown (approx. 1 hour of pre-amnioinfusion). labor. Her amniotic fluid index was first detected course to be severely decreased(5.1) at 37+5 weeks of pregnancy and hence follow up of it was made CASE 7 thenceforth. On November 19th and 20th all A 31-year-old woman, gravida 2, para 1 was measured amniotic fluid pockets were slit-like admitted on May 5th, 1991 due to rupture of and there was no change in the oligohydramnio- membrane at 41+2 weeks of pregnancy. tic state. On November 20th, with the start of Intravenous pitocin was infused from 6th to 8th of intravenous pitocin induction, early deceleration May with no success. On May 9th, 500ml of nor- showed up on tococardiographic monitoring and mal saline was amnioinfused. Pre-amnioinfusion after artificial rupture of the membrane, amnioin- findings consisted of variable decelerations(Fig. fusion of 450ml of normal saline was made, fre- 3) and an amniotic fluid index of 1.0 and follow- quency of early deceleration decreased to a ing the infusion, the decelerations disappeared significant degree and a female infant weighing and variability also showed improvement (Fig.4). 2.09kg with an Apgar score of 7 to 8 was nor- Flow of her amniotic fluid showed meconium mally delivered vaginally. Both mother and infant staining and under an impression of failure to were discharged following an uneventful hospital progress, an emergency cesarean section was Fig. 2. After the start of amnioinfusion, a dramatic improvement in the variability as well as disappearance of the decelerations can be seen.

made to give birth to a 3.51kg male infant with an Apgar score of 7 to 8 was prematurely deliv- an Apgar score of 3 to 6. Both mother and infant ered vaginally. The infant was then well taken were later discharged uneventfully. care of at neonatal intensive care unit, where his course was uneventful. Case 8 A 28-year-old woman, nullipara was admit- DISCUSSION ted on May 16, 1993 at 32+4 weeks of pregnancy with preterm labor pain and premature rupture of The first case of amnioinfusion was experi- membranes. Upon admission, the preterm labor mented with monkeys(Gabbe et a/. 1976). For pain was managed with intravenous Yutopar. the experiment, amniotic fluid was first removed On the 2nd admission day, the amniotic fluid to induce variable deceleration and by infusing index was measured at 4.1 and normal saline, disappearance of the deceleration was performed to obtain -a lecithinlsphin- was observed. The first report of amnioinfusion in gomyelin ratio of 4.2; and'on the next day human was made by Miyazaki and Taylor in amnioinfusion was made with 250ml of normal 1983, in which they observed recovery of vari- saline by transcervical route for the purposes to able fetal heart rate deceleration with amnioinfu- induce delivery and reduce fetal distress whilst sion in about half(Miyazaki and Taylor 1983). labor. Following the amnioinfusion, labor soon Miyazaki and Nevareze(l985) emphasized began and a male infant weighing 1.95kg with that the procedure is simple and requires only Fig. 3. With increasing frequency of contractions, variable decelerations appeared minimal equipment which is a three-way stop- In 1988, Gembruch and Hansman(l988) cock to divert the passage from the intrauterine attempted amnioinfusion in an effort to enhance pressure catheter tube to the intravenous exten- ultrasonographic resolution. Fisk et a1.(1991) sion tubing of the amnioinfusion solution bottle. pointed out the diagnostic uses of amnioinfusion The modes of amnioinfusion known are in improving delineation of anatomic structure many and the commonly employed ones are and also in determining rupture of membrane. In vesicoamniotic shunting (Manning et a/. 1986), casesl,2 and 3 of the current report it was possi- fluid infusion via an indwelling transcervical ble to make a diagnosis of gross fetal anomalies catheter(1manaka et a/. 1989), and serial trans- through amnioinfusion to make early interven- abdominal fluid infusion(Nico1ini et a/.1989). In tions in the pregnancies. If fetal anomaly is 1986, Manning et a/. had attempted vesicoamnio- detected in the early part of gestation with the tic shunting in urinary tract obstruction, but the help of amnioinfusion, termination should be rec- result was not satisfactory as the problem of pul- ommended. Romero et a1.(1988) advises termi- monary dysplasia persisted. As a solution to the nation of pregnancies suspected to have renal problem, Fisk et a1.(1991) suggested sequential agenesis. amnioinfusion in the cases of urinary tract During the process of amnioinfusion, it is obstruction. Another important factor for a suc- also possible to concurrently carry out chromo- cessful amnioinfusion is the proper placement of somal analysis to rule out any major fetal anoma- infusion needle and for those cases where this is lies and this procedure is especially meaningful not feasible, the recommended sites are to perform in second trimester oligohydramniotic between extremities, back, and the nape of the cases where 5-10% show chromosomal neck(Stringer et a/. 1990) anomaly. In case of premature rupture of mem- Fig. 4. Following the start of infusion, no more decelerations were observed.

branes, with amnioinfusion, the presence of leak- Amnioinfusion in oligohydramnios is known age can be determined by indigocarmine dye to bring about improvement in severe variable injection(Fisk et a/. 1991). deceleration by forming amniotic pockets in the Among the cases of this report, in case 4, to periphery of the umbilical cord which relieves the briefly review the pre-amnioinfusion fetal gas and cord from the pressure effect. Miyazaki and metabolic status,according to Lucie et a/. (1990) Nevareze(1985) obtained a success rate of 51 % the 5th percentile of umbilical vein pH of 33.5 as compared to 4.2% of non-amnioinfusion week old fetus is 7.360 meaning the fetus con- cases. However, according to a report by cerned was in severe acidemia, and PC02 and Goodlin et a1.(1990), the procedure guarantees a PO2 for a 34 week old fetal umbilical vein are success rate of only 15% and still is uncertain to considered both high and low if 41 and 25.4, predict. Decelerations in cases 4, 5, and 7 had respectively, and into which categories the fetus initially been late in case 4, and variable in cases belonged; however it was possible to observe a 5 and 7, and following amnioinfusion disappear- much improved biophysical profile score and ance of decelerations were noted. return of variability of fetal heart rate and also Nageotte et a1.(1985) prophylactically per- disappearance of decelerations upon amnioinfu- formed amnioinfusion in cases of premature rup- sion to validate the effect of the procedure in ture of membranes and reported a significant improving fetal distress. decrease in the incidence of variable fetal heart rate deceleration. 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