Significance and outcome of left heart hypoplasia in fetal congenital diaphragmatic hernia.

OBJECTIVE: In patients with a left-sided congenital diaphragmatic hernia (CDH), the left ventricle (LV) is often compressed and smaller than normal. The objective of this study was to investigate whether small left heart dimensions prenatally normalize after birth in patients with CDH, or whether prenatal indices of left heart size and flow predict postnatal outcome. METHODS: Clinical and echocardiographic data were reviewed for patients diagnosed with left-sided CDH prenatally. Cardiac dimensions and flows were compared with normative data. Among liveborn patients, pre- and postnatal Z-scores of left heart structures were compared, and associations between prenatal indices and outcome were assessed. RESULTS: Of 125 patients diagnosed prenatally with CDH, 111 had a left-sided defect. Of these, 85 were liveborn, including 20 with congenital heart disease. Gestational age-adjusted dimensions of fetal left heart structures, including aortic valve diameter, mitral valve (MV) diameter, LV long-axis, LV short-axis and LV volume, were all smaller than normal (P < 0.001). On average, the LV contributed 33 +/- 8% of combined ventricular output, lower than the normal 40-50%. Z-scores of left heart structures increased from the prenatal echocardiogram to the postnatal study, with average changes ranging from 0.56 +/- 1.68 (aortic valve) to 1.39 +/- 1.85 (LV volume). Among liveborn patients, there was no association between prenatal left heart Z-scores and postnatal survival. CONCLUSIONS: Hypoplasia of and reduced flow through the left heart are common among fetuses with CDH. After birth and CDH repair, left heart dimensions generally normalize, with adequate size to support a biventricular circulation, even when there is very low flow through the left heart in mid- and late-gestation.

Factors affecting technical success of fetal aortic valve dilation.

OBJECTIVE: We have reported previously that valve dilation enhances growth of cardiac structures and may prevent hypoplastic left heart syndrome (HLHS) in fetuses with critical aortic stenosis. We aimed to investigate maternal/fetal factors which may affect the technical success of fetal valvuloplasty, and to describe perinatal complications of the procedure. METHODS: This was a descriptive series of 22 fetuses diagnosed with critical aortic stenosis developing into HLHS which underwent intervention by valvuloplasty. Initially this was attempted using a percutaneous approach; reassessment after our first five attempts, only one of which was successful, led to the introduction of the option of laparotomy. Technical success was defined as balloon inflation across the aortic annulus and a broader jet through the aortic valve as assessed by Doppler. Data collected included body mass index, demographic variables, ultrasound findings and postprocedure interventions. RESULTS: Technical success increased significantly if maternal laparotomy was an option (83.3% vs. 20.0%, P = 0.017). Laparotomy was performed in 66.6% (12/18) of cases. There was a learning curve that showed an increase in success rate and decrease in need for laparotomy over the 3-year study period. Neither the need for laparotomy nor the chances of technical success were predictable by gestational age, body mass index or placental location. Tocolysis was limited to perioperative prophylaxis; one woman experienced wound infection and fluid overload. Postoperatively, three fetuses died and two delivered prematurely, 2 and 7 weeks after intervention. CONCLUSION: Fetal aortic valvuloplasty can be performed with technical success, with low fetal loss rate and few maternal complications. While the need for laparotomy cannot be predicted, having it available as an option improves the technical success rate.

The amniotic fluid as a source of cells for fetal tissue engineering.

PURPOSE: This study was aimed at determining whether fetal tissue constructs can be engineered from cells normally found in the amniotic fluid. METHODS: A subpopulation of morphologically distinct cells was isolated mechanically from the amniotic fluid of pregnant ewes (n = 5) and expanded selectively. Its lineage was determined by immunofluorescent staining against multiple intermediate filaments and surface antigens. Proliferation rates were determined by both oxidation and total DNA assays and compared with immunocytochemically identical adult and fetal sheep cells. Statistical analysis was by analysis of variance for repeated measures (ANOVA). After expansion, the amniocytes were seeded onto a polyglycolic acid polymer/poly-4-hydroxybutyrate scaffold. The resulting construct was analyzed by both optical and scanning electron microscopy. RESULTS: The immunocytochemical profile of expanded amniocytes was consistent with a mesenchymal, fibroblast/myofibroblast cell lineage. These cells proliferated significantly faster than comparable fetal and adult cells in culture. Amniocyte construct analysis showed dense, confluent layers of cells firmly attached to the scaffold, with no evidence of cell death. CONCLUSIONS: (1) Subpopulations of fetal mesenchymal cells can be isolated consistently from the amniotic fluid. (2) Mesenchymal amniocytes proliferate more rapidly in vitro than comparable fetal and adult cells. (3) Mesenchymal amniocytes attach firmly to polyglycolic acid polymer. The amniotic fluid can be a reliable and practical source of cells for the engineering of select fetal tissue constructs.

Radiofrequency ablation of human fetal sacrococcygeal teratoma.

OBJECTIVE: Fetuses with solid, highly vascularized sacrococcygeal teratomas can die as a result of the vascular steal syndrome. This is the first report in which a percutaneous technique, radiofrequency ablation, was used to interrupt blood flow to a sacrococcygeal teratoma in 4 human fetuses. STUDY DESIGN: A radiofrequency ablation probe was percutaneously inserted into the fetal tumor under ultrasonographic guidance. In 2 fetuses a significant portion of the tumor mass was ablated, whereas in the other 2 fetuses only the major feeding vessels were targeted. RESULTS: Two infants were delivered at 28 and 31 weeks' gestation, respectively, and are doing well. In 2 other cases hemorrhage into the tumor led to an unfavorable fetal outcome. CONCLUSION: Ablation of a majority of the tumor tissue in sacrococcygeal teratoma is not necessary and proved fatal in two instances. Targeted ablation of the feeding tumor vessels diminishes blood flow sufficiently to reverse high-output fetal heart failure.

Safety of chronic fetal vascular access in the sheep model.

OBJECTIVE: Long-term access to the fetal circulation has the potential to open up new perspectives in the treatment of numerous fetal anomalies. The purpose of this study was to investigate the safety of long-term catheterization of fetal placental vessels. METHODS: A midline laparotomy was performed in 4 time-mated pregnant ewes at 125 days' gestation (term 145 days). Placental vessels were exposed by a small uterine incision. A specially designed catheter was inserted into a placental vessel over a length of 3 cm, the distal end of the catheter was tunneled underneath the maternal skin and attached to a subcutaneous port implanted in the maternal flank. All pregnancies were allowed to go to term. RESULTS: Ewes and fetuses tolerated the placement of the catheter and port without complications. The catheter remained patent in all cases. All lambs were delivered vaginally at term and did not require resuscitation after birth. No fetal anomalies or growth restriction were noted. CONCLUSION: The ovine placental vessel can be accessed long term without complication.

Oesophageal perforation presenting as oesophageal atresia in a premature neonate following difficult intubation.

Iatrogenic oesophageal perforation in neonates is well recognized in the medical and surgical literature with intubation injury listed as a possible contributing mechanism besides nasogastric tube placement and suctioning. Diagnosis can be difficult and sometimes confused with other entities. With early diagnosis, nonsurgical management often leads to complete resolution in neonates. We report the case of a 1-day-old premature neonate who was brought to the operating room with the preliminary diagnosis of proximal oesophageal atresia with stump perforation and distal tracheo-esophageal fistula. His intubation for respiratory distress at birth had been difficult due to Pierre-Robin sequence with micrognathia. Oesophagoscopy in the operating room revealed a patent oesophagus but perforations in the pharynx and in the proximal oesophagus with the nasogastric tube entering the pharyngeal perforation. Oesophageal perforation and the limitations of the difficult airway algorithm in small neonates are discussed.

Hindbrain herniation develops in surgically created myelomeningocele but is absent after repair in fetal lambs.

OBJECTIVE: The purpose of our study was to determine whether prenatal repair of myelomeningocele prevents or reverses hindbrain herniation in the sheep model. STUDY DESIGN: A myelomeningocele was surgically created in fetal sheep. One group was repaired later in utero; the others were delivered without repair. After delivery, lambs were assessed for the presence of hindbrain herniation. RESULTS: In all lambs that had not undergone repair of the myelomeningocele, severe hindbrain herniation developed, whereas the brains of all lambs that had undergone fetal repair were normal. CONCLUSION: Prenatal repair of myelomeningocele prevents or reverses development of hindbrain herniation in the fetal lamb model.

Successful fetal sacrococcygeal teratoma resection in a hydropic fetus.

BACKGROUND/PURPOSE: The development of hydrops in a fetus with a sacroccocygeal teratoma (SCT) usually is a predictor of fetal demise; in utero resection may offer the only chance of survival. Although the authors had performed this procedure in 3 previous cases, they had no long-term patient survival. The authors report a successful case of in utero resection of a fetal sacrococcygeal teratoma. METHODS: The authors resected a fetal SCT from a 23-weeks-gestation hydropic fetus, using gradually tightening umbilical tapes at the tumor base, electrocautery, and careful sharp dissection. After a blood transfusion, the fetus suffered cardiac arrest but was resuscitated and returned to the uterus. RESULTS: Postoperatively, residual SCT growth ceased, and hydrops rapidly resolved. Five weeks after the procedure, the infant was delivered because of preterm labor, and, after resection of residual SCT, was discharged home at 3 months of age. She is now a healthy 3 year old. CONCLUSION: This case shows that successful fetal SCT resection and long-term patient survival is possible.

Successful resuscitation during fetal surgery.

After in utero resection of a sacrococcygeal teratoma coupled with a transfusion of packed red blood cells, a 23-week-gestation fetus had bradycardia. Chest compressions were begun and epinephrine, atropine, and sodium bicarbonate were given, while the fetus remained bathed in warm saline. After 3 rounds of drugs, and just before withdrawing support, the fetal heart resumed beating and normal cardiac function. Based on to this case, the authors developed a resuscitation protocol for fetal surgery.

Creation of myelomeningocele in the fetal rabbit.

OBJECTIVE: Myelomeningocele is a neural tube defect resulting in an exposed spinal cord, which leads to irreversible neurologic damage at birth. We proposed development of a fetal rabbit model of myelomeningocele to study in utero spinal cord injury and repair strategies. METHODS: New Zealand white rabbits (n = 10) at 22 days of gestation (term = 31 days) underwent laparotomy to expose the gravid uterus; a hysterotomy exposed the fetal hindlimbs and back. A three to four level lumbar laminectomy was performed, and the dura over the posterior spinal cord was removed. At 30 days of gestation, the does underwent C-section for fetal harvest, and total fetal number, length, weight, and the presence or absence of a spinal defect were recorded for all viable fetuses. RESULTS: All injured fetuses were smaller and weighed less than the nonoperated littermate controls, and histologic examination confirmed a spina bifida-like lesion of their spinal cords. CONCLUSIONS: We successfully created an exposed spinal cord defect in the fetal rabbit model similar to the lesion found in humans. Advantageous because of low animal cost, relatively large fetal size, multiple fetuses per pregnancy, and short total gestation, this model will allow us to study the mechanism of injury to the exposed spinal cord, and perhaps develop strategies to repair human myelomeningoceles.

Prune belly syndrome.

Prune belly is a lax, wrinkled abdominal wall and frequently is associated with other anomalies. The prune belly syndrome is a specific constellation of anomalies consisting of an abdominal wall deficient in muscular tissue, dilated urinary tract, and bilateral cryptorchidism. This group of anomalies is also called the Eagle-Barrett syndrome and the triad syndrome. In about 3 of 4 patients with the prune belly syndrome, there are associated malformations of the cardiopulmonary, gastrointestinal, and orthopedic systems.

Cord ultrasonic transection procedure for selective termination of a monochorionic twin.

Placental vascular communications can present a life-threatening problem in monochorionic twins when one fetus has a lethal anomaly. Although selective feticide is the best option for salvaging the normal twin, techniques normally employed (i.e. intracardiac potassium, air embolism) are not prudent given the common circulatory system. Furthermore, in monoamniotic, monochorionic twin gestations it is important to transect the umbilical cord completely to prevent entanglement of the dead fetus around the cord of the normal twin. We present two cases of monochorionic twins in which the cords were transected with a harmonic scalpel under ultrasonic guidance via one trocar. The harmonic scalpel is an instrument which can simultaneously coagulate and cut blood vessels or tissues. The cord ultrasonic transection procedure is a novel, minimally invasive technique which offers several advantages over the methods currently used for selective feticide in discordant monochorionic twin gestations.

In utero repair of rectal atresia after complete resection of a sacrococcygeal teratoma.

PURPOSE: A case of a fetus with a prenatally diagnosed sacrococcygeal teratoma that produced high-output cardiac failure, hydrops, rectal atresia, and urinary tract obstruction is presented. The unique prenatal surgical management along with the embryogenesis of tumor-related rectal atresia is discussed. CASE REPORT: A large fetal sacrococcygeal teratoma with a significant intrapelvic component was detected at routine ultrasound in a 35-year-old gravida 3 para 2. Fetal hydrops developed rapidly due to high-output cardiac failure from the vascular 'steal' by the growing tumor. The urinary tract was obstructed due to the intrapelvic tumors mass. At 27 weeks' gestation, the female fetus underwent hysterotomy, resection of the entire mass and urinary diversion via bilateral flank ureterostomies. The rectum was found to be completely atretic due to apparent encasement by the tumor. Pull-through anorectoplasty was carried out concurrently. At 30 weeks' gestation, the mother developed preterm labor and a 1.8-kg was delivered by cesarean section. The baby did very well for 3 days but had a cardiac arrest and died due to an atrial perforation by a transfemoral venous catheter. CONCLUSIONS: To our knowledge this is the first report of a complete prenatal resection of a sacrococcygeal teratoma with concomitant pull-through anorectoplasty for rectal atresia.

Slide tracheoplasty for congenital tracheal stenosis: a case report.

BACKGROUND/PURPOSE: A variety of techniques have been used to manage pediatric congenital tracheal stenosis. The authors report the technique of slide tracheoplasty for a child with long congenital tracheal stenosis. METHODS: A 2-year-old male presented with a history of stridor with feeding. Bronchoscopy findings showed 50% stenosis from complete cartilaginous rings, extending from 2.5 cm below the vocal cords to 2 cm above the carina. Through a neck incision, the trachea was exposed from the cricoid to both bronchi and transected at the midpoint of the stenosis. The upper trachea was split anteriorly to the area of stenosis just below the cricoid. The lower trachea was split posteriorly in the midline. Posterior dissection allowed sliding and anastomosis of both tracheal segments while the lateral vascular supply was left intact. A brace was placed to maintain cervical flexion, and the patient underwent extubation in the operating room. RESULTS: He recovered without complication and was dis charged on postoperative day 4. CONCLUSION: Slide tracheoplasty offers several advantages for tracheal reconstruction because it is performed with the native tracheal tissues, can be accomplished through a transverse collar incision, and can repair long stenoses without significant tracheal shortening.

One-stage correction of high imperforate anus in the male neonate.

PURPOSE: The aim of this study was to examine the feasibility, safety, and short-term outcome of complete one-stage repair of high imperforate anus in the newborn boy. METHODS: A retrospective review was conducted of five full-term male infants who underwent posterior sagittal anorectoplasty without a colostomy within the first 48 hours of birth. Preoperative imaging was performed to assess associated anomalies. All infants underwent cystoscopy before the perineal operation to determine the level of the urinary tract fistula, if present. After completion of the anoplasty, all were turned supine and the colon irrigated free of meconium. Follow-up ranged from 10 to 24 months. RESULTS: Laparotomy was not required for any patient. Three patients had a rectoprostatic urethral fistula, one a rectovesical fistula, and one no fistula (common wall at level of prostate). Tapering rectoplasty was required for only the one patient with a rectovesical fistula. There were no intraoperative complications. All patients passed stool within 12 hours after operation and took full feeding by 48 hours. The average hospital stay was 7 days. Postoperative and stenosis occurred in one patient secondary to parental noncompliance with the postoperative dilation regimen. There were no perineal wound complications. All patients have a strong urinary stream and defecate spontaneously without the aid of oral medication or rectal stimulation or enemas. CONCLUSIONS: One-stage repair of high imperforate anus in the male neonate is feasible without short-term genitourinary or gastrointestinal morbidity. Whether it is preferable compared with a delayed (two or three stage) repair depends on ultimate long-term anorectal function, which cannot be assessed for several years.

Transabdominal oxygenation using perfluorocarbons.

PURPOSE: Evaluation of the intraabdominal (intraperitoneal and intraluminal) administration of oxygen-saturated perfluorocarbon on both portal and arterial blood oxygenation. METHODS: Eight male rabbits were divided into the test (n = 5) and control (n = 3) groups. Each underwent intrajejunal, intraperitoneal, and intravascular (artery, portal vein) catheter placements along with ligation of the duodenum and the terminal ileum under general anesthesia. The test group received oxygen-saturated perfluorotripropylamine (FTPA), and the control group received oxygen desaturated FTPA. The oxygen delivery was assessed by serial blood gas measurements before and after the administration of FTPA. RESULTS: The administration of oxygen-saturated FTPA significantly increased the partial pressure of oxygen within both the arterial and the portal venous blood (PaO2, PpVO2) without significant changes in PCO2 values. Oxygen desaturated FTPA failed to show any effects on blood gas values. Compared with oxygen desaturated FTPA, oxygen-saturated FTPA increased PaO2, PpVO2, and oxygen saturation (artery, portal vein) significantly at some, but not all of the time-points measured. CONCLUSIONS: The intraabdominal administration of saturated FTPA improved both the portal venous and the arterial oxygenation. This new mode of oxygenation may be helpful as an adjunct to conventional oxygen delivery systems.

Maternal fertility is not affected by fetal surgery.

The purpose of this report is to assess the impact of fetal surgery on future maternal fertility, subsequent pregnancy outcome, and the incidence of pregnancy complications. Retrospective data were collected on 70 mothers who underwent fetal surgery between April 1981 and June 1996. Indications for open hysterotomy fetal surgery included congenital diaphragmatic hernia (n = 44), congenital cystic adenomatoid malformation of the lung (n = 11), urinary obstruction (n = 9), sacrococcygeal teratoma (n = 4), heart block (n = 1), and acardiac-acephalic twin reduction (n = 1). The following data were obtained: number of pregnancy attempts, number of successful pregnancies, pregnancy outcome including obstetrical and neonatal complications, and infertility after fetal surgery. There were 45 respondents, of whom 35 attempted subsequent pregnancies. Thirty-two were successful, resulting in 31 livebirths. Two women had a strong prefetal surgery history of infertility, 1 has only attempted to conceive for 3 months. We report this experience because the effect of open fetal surgery on futrue fertility is such an important question for our patients and referring physicians. This analysis suggests that hysterotomy and open fetal surgery has a negligible impact on maternal fertility.

Fetal neurenteric cyst causing hydrops: case report and review of the literature.

Routine prenatal ultrasound revealed a unilocular cystic mass associated with upper thoracic hemivertebrae that grew to 6 cm at 28 weeks and was associated with hydrops. A thoraco-amniotic shunt decompressed the cyst and resolved the hydrops, but the shunt occluded 17 days later. Preterm labour led to vaginal delivery at 31 2/7 weeks. Postnatally, the cyst was decompressed by thoracentesis due to respiratory distress. It was resected on day four of life. Severe tracheobronchomalacia was present post-operatively, presumably due to prenatal mass effect of the cyst. At one year of age, the child has recovered completely without adverse respiratory or neurological sequelae.

Perineal one-stage pull-through for Hirschsprung's disease.

PURPOSE: The aim of this study was to present the strategy of a one-stage repair of Hirschsprung's Disease (HD) performed via a transanal approach. METHODS: Ten consecutive neonates and one toddler underwent transanal repair for biopsy-proven HD. A rectosigmoid transition zone was suggested by contrast enema in all patients. The mean age at operation for the neonates was 4 days. A mucosal dissection was begun 0.5 cm proximal to the dentate line. Once the correct plane was established, up to 15 cm of bowel can be resected without ligating vessels or performing a transabdominal dissection. The proximal extent of dissection was delineated by the presence of ganglion cells seen on frozen section analysis. RESULTS: The mean operating time was 105 minutes. There were no intraoperative or postoperative complications. All children had the presence of ganglion cells confirmed postoperatively on permanent sections. The mean hospital stay was 2 days. All children averaged three to six bowel movements per day without oral or enema therapy. CONCLUSIONS: The perineal one-stage operative pull-through (POOP) procedure for Hirschsprung's disease is a quick and easy adaptation of a well-described technique of transanal mucosectomy. Long-term follow-up will be required to determine whether bowel function is better that that seen after traditional staged repairs.