Jean-Martin Laberge

Primary fetal hydrothorax : natural history and management

Primary fetal hydrothorax presents a wide spectrum of severity ranging from small, harmless effusions, to life-threatening thoracic compression. To define natural history and management, we reviewed 32 cases seen at two large perinatal centers from 1980 to 1987. Spontaneous resolution of the effusions was seen in three fetuses, all of whom survived. Three fetuses were electively terminated. The overall mortality was 53%. In the 24 untreated fetuses, sex and the presence of polyhydramnios did not influence mortality, but hydrops, gestational age less than 35 weeks at delivery, and bilateral effusions were associated with a poor prognosis. Five fetuses underwent in utero decompression. In four, thoracentesis was performed, with rapid reaccumulation of the effusion. All four died from pulmonary insufficiency. In the fifth fetus, a thoracoamniotic shunt permanently decompressed the effusion, with resolution of the hydrops, and delivery of a normal viable infant. We conclude that (1) primary fetal hydrothorax may resolve or progress to hydrops, necessitating close follow-up with ultrasound; (2) pulmonary hypoplasia as a result of undrained large pleural effusions may result in neonatal mortality; (3) the gestational age at both diagnosis and delivery, the development of hydrops, and bilaterality of effusions are important prognostic predictors; and (4) the fetus with large effusions and hydrops has a poor prognosis, and thoracic decompression with a thoracoamniotic shunt may prove life saving.

Fetal sacrococcygeal teratoma

Sacrococcygeal teratoma (SCT) is being diagnosed before birth with increasing frequency. We were recently consulted about management of a 22-week fetus with SCT and reviewed our experience (6 cases) and the literature. We found that most fetal SCT present from 22 to 34 weeks gestation with a uterus enlarged by the tumor and/or associated polyhydramnios; although the American Academy of Pediatrics Surgical Section clinical classification is an important prognostic indicator in neonatal SCT, it does not appear to predict outcome in fetal SCT; associated chromosomal abnormalities or life threatening anomalies are rare; presentation after 30-weeks gestation is a relatively good prognostic sign with fetal survival, after planned cesarean delivery, in 6 of 8 cases; and hydrops and/or placentomegaly in association with fetal SCT predicts fetal demise soon after diagnosis with 7 of 7 cases dying in utero.

Deleterious Effect of Tracheal Obstruction on Type II Pneumocytes in Fetal Sheep

It was previously shown that tracheal obstruction accelerated fetal lung growth and eventually reversed the pulmonary hypoplasia in experimental diaphragmatic hernia. We have successfully developed a reversible tracheal obstruction technique in fetal sheep using balloon occlusion and showed that 3 wk of obstruction induced significant lung growth of the same magnitude as the tracheal ligation. The purpose of this study was to examine the effects of 1 and 3 wk of tracheal occlusion on the alveolar cell population with specific attention to the type II pneumocytes. We first showed that 1 wk of occlusion induced a significant increase in lung weight and in alveolar surface area. We then used the surfactant protein C (SP-C) mRNA as a specific marker of differentiated type II pneumocytes. Total RNA was isolated from fetal sheep lung with or without tracheal occlusion, and Northern blots were hybridized with a cDNA probe specific for the sheep SP-C. The results show a dramatic decrease in SP-C mRNA expression (8.8-fold, p < 0.01). In situ hybridization showed a marked decrease in the density of cells expressing SP-C, as well as the amount of SP-C mRNA expressed by the cells. The effect was present as early as 1 wk of occlusion. The sparseness of type II pneumocytes was further confirmed by electron microscopy. We thus conclude that tracheal obstruction causes a profound decrease in the number of type II pneumocytes in the lungs. Given the crucial role of type II pneumocytes in surfactant production, we could speculate that, if tracheal occlusion is able to accelerate lung growth, the final product is probably surfactant-deficient.

Canadian Pediatric Surgical Network: a population-based pediatric surgery network and database for analyzing surgical birth defects. The first 100 cases of gastroschisis

PURPOSE Outcomes studies for gastroschisis are constrained by small numbers, prolonged accrual, and nonstandardized data collection. The aim of this study is to create a national pediatric surgical network and database for gastroschisis (GS) that tracks cases from diagnosis to hospital discharge. METHODS The 16-center network serves a population of 32 million. Gastroschisis cases are ascertained at prenatal diagnosis. Perinatal data include maternal risk and fetal ultrasound variables, delivery plan and outcome, a postnatal bowel injury score, intended and actual surgical treatment, and neonatal outcomes. Institutional review board-approved data collection conforms to regional privacy legislation. Deidentified data are centralized and accessible for research through the network steering committee. RESULTS To date, 114 cases of pre- and/or postnatal gastroschisis have been uploaded. Of 106 live-born infants (40 [38%] by cesarean delivery), 100 had complete records, and overall survival to discharge was 96%, with a mean survivor length of stay (LOS) of 46 days. Infants treated with attempted urgent closure (61%) had significantly shorter LOS (42 vs 57 days; P = .048) but comparable LOS compared with those treated with silos and delayed closure. Fetal bowel dilation 18 mm or greater did not predict a difference in outcome. CONCLUSION Population-based databases allow rapid case accrual and enable studies that should aid in the identification of optimal perinatal treatment.

Effect of hospital case volume on outcome in congenital diaphragmatic hernia: the experience of the Canadian Pediatric Surgery Network

PURPOSE Despite advances in neonatal care of congenital diaphragmatic hernia (CDH), a significant variation exists in the mortality rates reported by individual centers. Center experience (reflected by case volume) may contribute to this variation in outcome. The aim of the study was to determine whether CDH mortality is affected by hospital case volume. METHODS The CDH cases were abstracted from a disease-specific, 16-hospital, national network. Thirteen hospitals participated in this study. Anonymized hospitals were categorized as either high (>6 cases) or low-volume (<or=6 cases) centers (HVC, n = 6; LVC, n = 7) according to the median case number per center. Risk-adjusted (Score for Neonatal Acute Physiology, version II [SNAP-II] score) mortality rates were compared between HVC and LVC. RESULTS One hundred twenty-one CDH cases were identified. Overall in-hospital survival was 81%. No significant difference in SNAP-II score was observed between HVC and LVC. Of 97 (15%) infants treated in 6 HVC, 15 (15%) died compared to 8 (33%) of 24 in 7 LVC (P < .05). CONCLUSION Hospital case volume may be partially responsible for mortality rate variation in CDH. This result requires careful analysis, as case volume may merely be a surrogate for other predictive variables.

Vascular complications after pediatric liver transplantation

From February 1986 to July 1994, 81 hepatic transplantations were performed in 73 children, with an overall patient survival rate of 83%. Forty-two patients received whole-liver grafts (WLG) and 39 had reduced-size grafts (RSG). The mean patient weight was 19.7 kg, with 29 patients weighing less than 10 kg. Seventeen vascular complications (21%) occurred in 13 children: 8 (10%) had hepatic artery thrombosis (HAT), 5 (6%) had portal vein thrombosis (PVT), 1 had both HAT and PVT (1%), and 3 (4%) had aortic conduit perforation (ACP). There was no significant difference in the incidence of HAT between RSG (5%) and WLG (14%) or between children weighing less than 10 kg (10%) and those weighing more than 10 kg (10%). The site of arterial reconstruction, end-to-end to the recipient common hepatic artery or end-to-side to the infrarenal aorta, had no significant effect on the occurrence of HAT (7% v 8%), but HAT occurred in 2 of 6 cases (33%) in which an aortic conduit was used. PVT documented in 5 cases (6%) was associated with technical complications (2), preduodenal portal vein (2), and a circulating cardiolipid antibody (1), and required thrombectomy, with no graft loss. Combined HAT and PVT was found in one patient 2 years postretransplantation for HAT. Although graft function is normal, portal hypertension persists. The aortic conduit, used in six patients, led to arterial perforation (3), HAT (2), and death (2). Of the 8 cases of HAT, 1 was diagnosed during autopsy and 7 occurred within 30 days and required retransplantation (6) or thrombectomy with rearterialization (1).(ABSTRACT TRUNCATED AT 250 WORDS)

Fetal surgery in the primate III. Maternal outcome after fetal surgery

Maternal safety and future reproduction potential are paramount considerations in fetal surgery. In a series of 102 fetal surgical procedures on time-dated pregnant monkeys, we examined the maternal complications, the potential for future pregnancy, and the effects of uterine staples used for hysterotomy and uterine closure. There were significant maternal complications associated with the development of the present techniques for fetal surgery including 3 maternal deaths, 5 uterine ruptures, and 5 cases of wound infection of dehiscence. All were preventable with knowledge gained from this experience. Compared with a control unoperated breeding colony, fetal surgery did not interfere with subsequent reproductive capacity in animals that had uterine closure with absorbable sutures. However, metal staple hysterotomy resulted in a markedly decreased fertility rate probably related to exposure of the endometrial cavity to a permanent foreign body. Although serious maternal complications occurred in this series, many are avoidable as we improve both our obstetric management and our anesthetic and surgical techniques. Prenatal intervention carries considerable maternal risk and should not be attempted clinically under any but the most rigorous conditions.

Institutional practice and outcome variation in the management of congenital diaphragmatic hernia and gastroschisis in Canada: a report from the Canadian Pediatric Surgery Network

BACKGROUND Perinatal management of congenital diaphragmatic hernia (CDH) and gastroschisis (GS) remains nonstandardized and institution specific. This analysis describes practice and outcome variation across a national network. METHODS A national, prospective, disease-specific database for CDH and GS was evaluated over 4 years. Centers were evaluated individually and defined as low (low-volume center [LVC]) or high (high-volume center [HVC]) volume based on case mean. RESULTS Congenital diaphragmatic hernia. Two hundred fifteen liveborn cases were studied (mean, 14.3 cases/center) across 15 centers (8 LVCs and 7 HVCs). Significant interinstitutional practice variation was noted in rates of termination (0%-40%) and cesarean delivery (0%-61%). Centers demonstrated marked variation in ventilation strategies, vasodilator and paralytic use, timing of surgery, and rates of primary closure. Overall survival was 81.4% (LVC, 76.9%; HVC, 82.4%; P = .43). Gastroschisis. Four hundred sixteen cases were investigated (mean, 26 cases/center; range, 6-72) across 16 centers (10 LVCs and 6 HVCs). Cesarean delivery rates varied widely between centers (0%-86%) as did timing of closure (early vs delayed, 1%-100%). There was no difference in length of stay, days on total parenteral nutrition, and overall survival (94.3% vs 97.2%; P = .17) between LVCs and HVCs. CONCLUSIONS The existence of perinatal practice and outcome variation for GS and CDH suggests targets for improved delivery of care and justifies efforts to standardize treatment on a national basis.

Laparoscopic cholecystectomy : a treatment option for gallbladder disease in children

Laparoscopic cholecystectomy was performed safely in two children ages 7 and 15 years. Special considerations were required in the younger child because of the discrepancy between the length of the instruments and the size of the peritoneal cavity. Both children remained in hospital less than 24 hours and were able to resume normal diet and activity quickly. Pediatric surgeons with special training in laparoscopic surgery may want to use this treatment modality for children with biliary tract disease.

Timing of repair of congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation support

Treatment of congenital diaphragmatic hernia (CDH) has undergone a revolutionary change in philosophy, from previous urgent repair to the present practice of stabilization and delayed repair. However, when extracorporeal membrane oxygenation (ECMO) is required, many people believe that the risk of postoperative pulmonary hypertension (PPHN) mandates hernia repair while on ECMO. This report details the experience in two ECMO centers with stabilization, ECMO if required, and CDH repair post-ECMO. All CDH patients symptomatic in the first hour of life with a gestational age of at least 34 weeks during the period were reviewed retrospectively. Standard criteria were used to select patients for ECMO. High-frequency jet or oscillating ventilators and nitric oxide were not routinely available throughout the study period, but were used in some of the more recent patients. A total of 60 patients presented to the two centers; 24 cases were stabilized with conventional management, repair of the CDH was done elective, and survival was 100%. Eight patients were referred after having repair elsewhere; six survived (75%). The two deaths were attributable to associated lethal lesions--complex cyanotic heart disease and alveolar capillary dysplasia. Eight patients who required ECMO were managed with the intention of repairing the defect on ECMO. Four survived (50%). Two patients died before repair. Twenty patients were managed with ECMO, with the intention of repairing the defect after decannulation. Overall survival was 13 (65%), deaths were caused by pre-ECMO hypoxia, pulmonary insufficiency, and associated cardiac disease. No patient had recurrent pulmonary hypertension after late repair.(ABSTRACT TRUNCATED AT 250 WORDS)