Pericardial hemangioma presenting as thoracic mass in utero.

Pericardial hemangiomas are rare lesions. We present the case of an infant who was referred to our fetal diagnosis and treatment group for the presence of a left thoracic mass, pleural effusion, and mediastinal shift on fetal ultrasound. The characteristics of the lesion suggested the presence of a pulmonary sequestration. A chest radiograph done at birth was normal. At 2 weeks of age, an enhancing lesion of the left pericardium was identified on chest CT. A cardiac MRI demonstrated enhancement of the mass on T2-weighted images. The patient underwent thoracoscopic assessment of the mass for diagnostic purposes. Multiple lesions were identified along the left pericardium and diaphragm. A frozen section biopsy revealed a hemangioma. The natural history for hemangiomas is gradual regression; however, they may increase acutely in size and cause symptoms prior to involution. Investigations should be performed to identify the involvement of other organs. This case illustrates the need to closely follow all patients with prenatally diagnosed thoracic masses with CT imaging, even when they are asymptomatic and have a normal chest radiograph at birth.

Gastrointestinal duplications.

BACKGROUND/PURPOSE: The aim of this study was to review the presentations of gastrointestinal duplication (GID) and to assess the influence of prenatal diagnosis on treatment. METHODS: Retrospective review of all GID at 2 pediatric hospitals from 1980-2002 was conducted. RESULTS: Seventy-three patients (M43:F30) were identified: 21 neonates, 28 infants (1 to 24 months), 15 children (1 to 10 years), 9 adolescents (>/=11 years). GID location by frequency was ileum (31.5%), ileocaecal valve (30.2%), duodenum (9.6%), stomach (8.2%), jejunum (8.2%), colon (6.8%), and rectum (5.5%). In neonates and infants, vomiting and distension were the most common presentations. Volvulus, caused by a duplication, occurred in 23.8% of neonates and caused the death of one neonate. Intussusception was identified in 10.9% of patients. In older children and adolescents, pain and vomiting were the most common associations. Six of these patients were being treated for Crohn's disease, with the diagnosis of duplication made at laparotomy. Eighteen patients had a prenatal diagnosis by ultrasound scan, with 77.2% of these asymptomatic after birth. Most prenatal diagnoses occurred after 1991 (77.8%). When comparing an earlier period (1980 to 1991; 29 patients) with the current (1992 to 2002; 44 patients), a greater proportion of the latter patients were asymptomatic (36.4 v 13.8%) and had a lower incidence of complications (volvulus/intussusception). CONCLUSIONS: GID can lead to life-threatening complications. Prenatal diagnosis should lead to expeditious postnatal investigation and treatment before the onset of symptoms or complications. GID in older children can mimic Crohn's disease. Laparoscopy/laparotomy should be considered in patients with atypical Crohn's disease or when the diagnosis of an intraabdominal mass is unclear.

Use of antenatal steroids to counteract the negative effects of tracheal occlusion in the fetal lamb model.

Tracheal occlusion (TO) in fetal lambs induces pulmonary hyperplasia but has negative effects on type II cells. The purpose of this study was to determine whether antenatal steroids could reverse the adverse effects of TO on lung maturation in fetal lambs. Sixteen time-dated pregnant ewes (term, 145 d) and 24 of their fetuses were divided into six groups: 1) TO at 117 d gestation; 2) TO at 117 d with a single maternal intramuscular injection of 0.5 mg/kg betamethasone 24 h before delivery; 3) TO at 117 d and release of the occlusion 2 d before delivery; 4) TO and release of the occlusion with maternal steroids; 5) unoperated controls without antenatal steroid treatment; and 6) unoperated controls, littermates of groups 1-4, treated with antenatal steroids. All fetuses were killed at 137 d gestation. Outcome measurements consisted of lung weight-to-body weight ratio; lung morphometry determined by mean terminal bronchial density; and assessment of type II pneumocytes by in situ hybridization to the mRNA of surfactant proteins B and C. Lung weight-to-body weight ratio and mean terminal bronchial density were significantly different among groups with TO and controls, indicating increased lung growth and structural maturation. The density of type II pneumocytes was markedly decreased by TO. Release 2 d before sacrifice significantly increased the density and surfactant activity of type II pneumocytes, but to levels still far from controls. Steroids alone had an effect similar to release. An additive effect was noted with steroids and 2-d release resulting in type II cell density comparable to controls. After fetal TO, a single maternal intramuscular dose of 0.5 mg/kg of betamethasone 24 h before delivery allows partial recuperation of the type II pneumocytes, an effect that is potentiated by 2-d release.

Endoscopic retrograde cholangiopancreatography in children: A surgeon's perspective.

PURPOSE: The aim of this study was to review the indications, success rate, and complications of endoscopic retrograde cholangiopancreatography (ERCP) in the pediatric age group. METHODS: From 1990 to 1999, 21 ERCP procedures were attempted in 20 patients. They consisted of 8 boys and 12 girls whose age ranged from 4 to 17 years (mean, 11.3 years). Fourteen were performed under deep sedation (mean age, 12.8 years), and 7 were done under general anesthesia (mean age, 7.6 years). All ERCP procedures were performed by experienced adult endoscopists. RESULTS: The indication for ERCP was biliary in 15 patients. Eleven had suspected choledocholithiasis by either ultrasound scan, intraoperative cholangiogram or magnetic resonance imaging (MRI). In 6 cases, the ERCP was done for pancreatic pathology. In 11 patients, the ERCP was diagnostic only, and in 10 a therapeutic procedure was done. The overall success rate was 90.5%. Post-ERCP complications consisted of 6 episodes of pancreatitis (28.5%), 4 of which followed a therapeutic procedure, and 1 episode of bleeding. Pancreatitis resolved 2 to 6 days post-ERCP. The patients underwent follow-up between 2 and 56 months after the ERCP (mean, 11 months). CONCLUSIONS: The authors conclude that even in experienced hands, ERCP in the pediatric population has a much higher complication rate than in adults (33.3%). We recommend that very specific indications be met before subjecting a pediatric patient to an endoscopic retrograde cholangiopancreatography.

Pulmonary structural maturation and pulmonary artery remodeling after reversible fetal ovine tracheal occlusion in diaphragmatic hernia.

PURPOSE: Congenital diaphragmatic hernia (CDH) is associated with thickened pulmonary arteries (PA) contributing to pulmonary hypertension. In the current study, the effects of antenatal glucocorticoids and reversible tracheal occlusion (TO) on PA structure were assessed in a hypoplastic lung model. METHODS: A left-sided CDH was created in fetal lambs at 80 days gestation, TO at 108 days, and release of the occlusion (TR) at 129 days. All were given 1 dose of maternal glucocorticoids at 135 days. At 136 days (term, 145 days), the fetus was delivered by cesarian section. CDH (n = 7), CDH + TO (n = 6), CDH + TO + TR (n = 6), and unoperated twin controls (n = 16) were compared. Outcome measurements were (1) lung growth, represented by lung weight to body weight ratio (LW/BW), (2) lung structural maturation, which is inversely proportional to mean terminal bronchiole density (MTBD), (3) PA medial and adventitial areas (square micrometers), (4) lung capillary load, which is the ratio of vessel surface area (SA) to tissue SA ratio. RESULTS: CDH lungs were hypoplastic with a low LW/BW and high MTBD. The small PAs (<75 microm) of CDH had an increased medial area, indicating increased muscle mass and an increased adventitial area. CDH + TO +/- TR increased LW/BW and achieved normal structural lung maturity with a low MTBD. Only CDH + TO thinned the PA medial area closer to control values. The adventitial area remained thick in CDH +/- TO +/- TR when compared with controls. All 4 groups had similar capillary load. CONCLUSIONS: TO may be especially important for PA remodeling in the latter part of gestation, because TR 1 week before delivery prevents thinning of the small PAs in CDH. The shaping achieved by TO in terms of lung growth, structural maturity, and pulmonary artery medial area thinning may prove beneficial in lessening the severity of the associated pulmonary hypertension in CDH.

The multiple facets of pulmonary sequestration.

PURPOSE: The goal of this study was to identify the proportion of sequestrations that were atypical or associated with other entities, such as congenital cystic adenomatoid malformations, communicating bronchopulmonary foregut malformations, bronchogenic cyst, and scimitar syndrome. METHODS: All charts of patients with pulmonary sequestration admitted at 2 children's hospitals from 1982 to July 1999 were reviewed retrospectively. The authors included all anomalies with a systemic arterial supply or without bronchial connection. RESULTS: Only 22 of the 39 patients (56%) had a classic isolated extralobar or intralobar sequestration, whereas the others presented with a spectrum of anomalies. Of the 13 cases diagnosed prenatally, 85% were asymptomatic at birth. In contrast, 26 cases diagnosed postnatally were all symptomatic, with those patients less than 2 weeks old presenting with various degrees of respiratory distress, and those older than 2 weeks old presenting with respiratory infections. The correct diagnosis was made preoperatively in 59% of cases. Only 4 patients did not undergo resection of their lesion, of which, 1 underwent interventional radiology with embolization of the anomalous arterial supply. Follow-up issues of importance included pneumonia, asthma, gastroesophageal reflux, and pectus excavatum. CONCLUSIONS: Sequestrations represent a spectrum of anomalies that overlap with other lung lesions. To facilitate management, they should be described according to their (1) connection to the tracheobronchial tree, (2) visceral pleura, (3) arterial supply, (4) venous drainage, (5) foregut communication, (6) histology, (7) mixed/multiple lesions, and (8) whether there are associated anomalies. Surgeons should be aware that approximately 50% of sequestrations could be atypical or associated with other anomalies. This should be kept in mind when weighing the benefits of resection versus conservative management of pulmonary sequestrations.

Clinical versus sonographic evaluation of acute appendicitis in children: a comparison of patient characteristics and outcomes.

PURPOSE: Abdominal sonography has gained popularity in establishing the diagnosis of appendicitis in children with equivocal clinical presentations. However, no clear outcome benefits have been demonstrated to date. The authors conducted a retrospective study to compare the characteristics and outcomes of patients undergoing appendectomy after clinical evaluation only with those undergoing the procedure after sonography. METHODS: The charts of 454 consecutive patients undergoing appendectomy for acute appendicitis between January 1, 1998 and December 4, 1999 were reviewed. Patients operated on after clinical evaluation only were compared with patients operated on after abdominal sonography. RESULTS: Forty-two percent of patients (n = 191) constituted the sonography group. When compared with the clinical group, these patients had higher prevalence of female gender (52% v 38%; P =.004), longer symptom duration (2.2 +/- 2.5 v 1.6 +/- 1.6 days; P =.003), higher incidence of preoperative in-patient observation (19% v 4%; P <.001), longer duration between evaluation and operation (8.0 +/- 3.9 v 4.9 +/- 2.9 hours; P <.001), higher incidence of normal appendices on pathologic examination (13% v 6%; P =.006), and higher incidence of postoperative abscesses or phlegmons (4.4% v 1.2%; P =.04). The groups did not differ significantly in age, hospital stay, incidence of complicated appendicitis, or incidence of wound infection. CONCLUSIONS: Patients undergoing sonography before appendectomy have a longer delay before operation, a higher rate of misdiagnosis, and more postoperative complications. Limiting sonography to truly equivocal cases and using it early in the diagnostic workup may improve outcomes in this group of patients.

Outcome of the prenatally diagnosed congenital cystic adenomatoid lung malformation: a Canadian experience.

UNLABELLED: Congenital cystic adenomatoid malformation of the lung (CCAM) is diagnosed by prenatal ultrasonography with an increasing frequency but controversy persists as to its prognosis and prenatal management. METHOD: A multi-institutional study of cases of CCAM diagnosed antenatally identified by ultrasonographers and by a review of hospital charts. RESULTS: We obtained 48 cases from five centers. We estimate the incidence of CCAM at 1:25,000 to 1:35,000 pregnancies. The incidence of voluntary abortions was 15% (7/48), of spontaneous abortions 2% (1/41) and of postnatal death 10% (4/40). One of the postnatal deaths was from trisomy 18. Of the 7 aborted fetuses, 2 had multiple malformations and 1 had severe hydrops and oligohydramnios; the other 4 had a large mass with mediastinal displacement but without hydrops. When pregnancy was allowed to continue, 56% of the lesions regressed spontaneously, even though one third of these had initial progression. In 17 cases (42%) the mediastinal shift corrected itself, sometimes by simple growth of the fetus but most often by a decrease in the size of the lung mass. In 1 fetus, repeated needle decompressions followed by double-pigtail catheter drainage of large cysts allowed regression of hydrops. Despite this, neonatal death occurred from pulmonary hypoplasia. CONCLUSION: CCAM can lead to fetal or neonatal demise from hydrops, lung hypoplasia, prematurity or severe associated malformations, but has a good prognosis in the majority of cases.

Surfactant levels after reversible tracheal occlusion and prenatal steroids in experimental diaphragmatic hernia.

BACKGROUND/PURPOSE: In normal lungs, fetal tracheal occlusion (TO) induces lung growth but decreases the number of type II cells; this is remedied if TO is released (TR) before delivery. In the current study, the effects of TO with or without TR on pulmonary structure and surfactant were assessed in the ovine model in which lung hypoplasia was induced by creation of a diaphragmatic hernia (CDH). METHODS: A left-sided CDH was created in fetal lambs at 80 days gestation; TO was done at 108 days; and TR at 129 days. All ewes were given 1 dose of glucocorticoids at 135 days. At 136 days, the fetus was delivered. Lung weight to body weight ratio, mean terminal bronchiole density, type II cell density, bronchoalveolar lavage fluid (BAL) phosphatidylcholine (PC), BAL surfactant protein A (SP-A) and B (SP-B), and lung tissue SP-A and SP-B were assessed in CDH, CDH with TO, CDH with TO and TR, and controls. RESULTS: CDH lungs were hypoplastic and structurally immature, but had increased type II cell density. TO with or without TR caused lung growth with normalization of lung parenchymal architecture and type II cell density. Although the BAL SP-A and BAL SP-B were similar in all 4 groups, the BAL PC was low in CDH with or without TO or TR. Also, lung tissue SP-B levels were low in CDH with or without TO or TR. However, lung tissue SP-A levels were normal in CDH, but low in CDH with TO with or without TR. CONCLUSIONS: Despite the finding that lung morphology was improved in CDH with TO with or without TR animals, surfactant content and composition remained abnormal. Although surfactant secreted early by the fetus into alveolar spaces contained normal levels of BAL SP-A and BAL SP-B, the low levels of BAL PC and low lung tissue stores of SP-B indicate that these experimental lambs may experience respiratory insufficiency soon after birth. This implies that prophylactic surfactant at birth might be beneficial for CDH.

Tracheal side effects of endoscopic balloon tracheal occlusion in the fetal lamb model.

OBJECTIVE: To evaluate effects of in-utero endoluminal balloon tracheal occlusion (TO) as suggested for the treatment of Congenital Diaphragmatic Hernia (CDH) on the higher airways of a fetal lamb model. STUDY DESIGN: Fetuses from time-dated pregnant ewes underwent at 94 days (term=145 days) in-utero tracheal occlusion. In study animals an endoluminal, detachable balloon was placed by tracheoscopy. For that purpose a 1.2mm fibre-optic, semi-rigid endoscope and a medically graded latex balloon were used. In group I (n=9) lambs were delivered after 2 weeks. In group II (n=8) the tracheal occlusion was released after 2 weeks, to allow in-utero recovery until term. In positive control animals (group III; n=5) the trachea was clipped at 98 days and fetuses were harvested near term by cesarean section. A total of 17 contralateral littermates in multiple pregnancies served as negative controls. After macroscopic inspection of the trachea, sections were evaluated by light microscopy. Alterations were scored with an empirical interval score for each of the different anatomical elements in the fetal trachea (epithelium, submucosa, cartilage, pars membranacea). RESULTS: For the animal experiments in group I, all balloons were found in place and according to the pulmonary response they were obstructive. Tracheas were macroscopically dilated by the plug mainly due to elongation of the pars membranacea. The total histologic score was correlated to the increase in circumference (mean increase: 3.0mm). In nearly all cases, the tracheal epithelium at the level of the plug had lost its typical folding pattern. In 44% of cases, local epithelial defects were observed and in 33% of cases there was squamous metaplasia. A chronic inflammatory response was present in over half of the cases, sometimes with giant cell reaction. In group II (the in-utero recovery group) the total score was significantly lower than in group I, with much less prominent unfolding and absence of epithelial defects. Squamous metaplastia was still present in half of the cases; whereas inflammatory responses were less frequent. In group III the trachea expanded normally after removal of the clip. The epithelium had compacted folds, and cilia were well preserved. In two animals however, intraluminal synechia were observed. Below the level of occlusion animals of groups I and II all showed areas of unfolding, but without metaplasia or epithelial defects. CONCLUSION: Tracheal obstruction by means of endoluminal plugging has been suggested as an alternative in-utero treatment for congenital diagphragmatic hernia. The balloon causes mild epithelial changes, such as unfolding, limited epithelial defects (<25% of the exposure surface) and local inflammatory changes. These changes disappear nearly completely following in-utero unplugging during the rest of gestation. Unfolding of the epithelium is also seen in the trachea under the plug.

Should malrotation in children be treated differently according to age?

PURPOSE: The aim of this study was to better define the mode of presentation, rate of volvulus, and surgical findings in children younger than 2 versus older than 2 years of age with malrotation. METHODS: The authors reviewed the charts of all patients with malrotation admitted to their hospital between January 1980 and December 1998, excluding patients having malrotation as a secondary finding. RESULTS: An upper gastrointestinal series was done in 90 patients (6% falsely negative) and a barium enema in 20 patients (40% read as normal). Fifty-eight patients had 114 associated congenital anomalies. Volvulus was found at the time of surgery in 28 patients, 5 of whom were older than 2 years. Three presented with acute symptoms and 2 with chronic symptoms. Surgery was performed by laparotomy in 103 patients and by laparoscopy in 3. Mean length of stay was 13.6 days. Mean follow-up was 19 months. Death occurred in 4 patients; postoperative bowel obstruction was seen in 3 patients (only 1 required surgery). CONCLUSIONS: Children with malrotation who are older than 2 years old have a significant risk of volvulus that is difficult to predict radiologically. They require surgical attention even if asymptomatic. Laparoscopy allows evaluation of the base of the mesentery and completion of the Ladd's procedure.

Prenatal percutaneous needle drainage of cystic sacrococcygeal teratomas.

Prenatal ultrasound (US) permits in utero diagnosis of sacrococcygeal teratoma (SCT), follow-up of tumor size, and the early identification of complications, allowing for a more timely and appropriate delivery. The recommended management of large SCTs is delivery by cesarean section (CS) to prevent dystocia, tumor rupture, hemorrhage, and death. However, even delivery by CS can be difficult, necessitating a large hysterotomy that adds to maternal morbidity. The authors report two cases of cystic SCTs in which prenatal percutaneous drainage allowed for an uncomplicated vaginal delivery. In the first case, a large unilocular cystic SCT was diagnosed at 31 weeks' gestation on prenatal US. The fetal presentation was breech, and the mass was steadily increasing in size, preventing spontaneous version. At 37 5/7 weeks, the cyst was percutaneously drained under US guidance allowing for successful external version. Repeat drainage just before induction of labor permitted a successful vaginal delivery. In the second case, the cystic SCT was percutaneously drained just before induction of labor at full term, again allowing for an uncomplicated vaginal delivery. Prenatal percutaneous needle drainage of cystic SCTs offers an alternative to CS that results in decreased risks for both mother and fetus.

25 years' experience with lymphangiomas in children.

BACKGROUND/PURPOSE: The management of lymphangioma in children is challenging because complete resection is difficult to achieve in some cases, and recurrences are common. The authors reviewed their experience to assess the risk factors for recurrence and the role of nonoperative treatment. METHODS: A retrospective study over a period of 25 years was carried out. One hundred eighty-six patients with 191 lesions (five patients with de novo lesions in different sites) were treated. There were 98 boys and 88 girls. The average age at diagnosis was 3.3 years (range, fetal life to 17 years) and the average size 8 cm in diameter. Histocytological confirmation was obtained in all patients. The involved sites were head and neck, 89 patients (48%); trunk and extremities, 78 patients (42%); internal or visceral locations (eg, abdominal and thorax), 19 patients (10%). The treatment consisted of macroscopically complete excision in 145 patients (150 lesions, of which five were recurrences in different sites), partial excision in 10 patients, aspiration in five patients, laser excision in 10 patients, biopsy only in four patients, drainage and biopsy in two patients, and injection of sclerosing agents in 10 patients. RESULTS: There were 54 recurrences; 44 underwent excision (five of them more than once), and five regressed spontaneously on follow-up. Five other recurrences were stable and not progressing. Recurrences, (defined as clinically obvious disease), were found to be 100% after aspiration, 100% after injection, 40% after incomplete excision, 40% after laser excision, and 17% after macroscopically complete excision. The recurrence rate in the last group was the highest in the head (33%), the least in the internal locations (0%), and intermediate for the cervical location (13%). There were no significant differences, in terms of outcome, between those who had their surgery immediately at the time of diagnosis (n = 101) and those who had delayed surgery (n = 85). CONCLUSIONS: There were fewer recurrences after macroscopically complete excision. Aspiration and injection had the highest recurrence rate. Risk factors for recurrence included location, size, and complexity of lesions. A period of observation may be useful for infants to facilitate complete excision. In the present series, spontaneous regression was infrequent and was seen more often with recurrent lesions.

Single-port tracheoscopic surgery in the fetal lamb.

BACKGROUND/PURPOSE: Endoscopic fetal surgery could help avoid many of the problems associated with open fetal surgery, but the use of multiple ports may be too traumatic to the membranes. The authors describe a single-port technique of tracheoscopic surgery in the fetus. METHODS: Time-dated pregnant ewes (95 to 105 days; term, 145 days) underwent midline laparotomy under general halothane anesthesia. A 5-mm-diameter balloon-tipped cannula was introduced in the uterus by Seldinger technique. A 1.2-mm semirigid mini-endoscope, fitted inside a 9F, 20 degrees curved sheath, was introduced under continuous, low-pressure irrigation, inside the fetus' mouth, and advanced into the trachea. RESULTS: Endotracheal procedures, including temporary (n = 11) and permanent balloon tracheal occlusion (n = 30) and placement of a barbed guide wire for endotracheal occlusion device insertion (n = 12), were performed by introducing a 1-mm diameter instrument alongside the telescope. These were successfully performed in 52 of the 53 fetuses. The rigidity of the telescope allowed controlled access to the pharynx; its curve allowed full tracheobronchial endoscopy with the fetus in utero. CONCLUSIONS: The present technique marries the control and optical quality of a rigid endoscope with the physiological curve only a flexible instrument could offer until now. The types of procedures performed with this technique illustrate its potential as a research tool; the size (1.2-mm diameter), shape, and optical qualities of the telescope should make clinical applications possible.

Alternative technique for Nd: YAG laser coagulation in twin-to-twin transfusion syndrome with anterior placenta.

Nd: YAG laser coagulation is used to treat severe twin-to-twin transfusion syndrome (TTS). Success of the technique depends on visualization of the placenta, the fetal membranes and the targeted vessels, as well as obtaining an optimal inclination angle for laser coagulation. In the rare case of an extensive anterior placenta, it may be difficult to achieve these conditions using the percutaneous approach. Here, we propose an alternative to the percutaneous procedure. Modifications involve an open access and the use of a flexible cannula and bent scope. An extraplacental area, usually at the fundus, is identified by B-mode and color Doppler imaging. A mini-laparotomy is made under general anesthesia. The viscera are retracted and the cannula is inserted under direct view and ultrasound control by the Seldinger technique. The curved fiberscope is passed through the flexible cannula, allowing adequate inspection of the placenta, and target vessels can be coagulated at an angle close to 90 degrees. After the procedure, the uterus is closed primarily to prevent postoperative leakage of amniotic fluid or hemorrhage. This technique has been successfully used in six patients with TTS and a completely anterior placenta, with a gestational age between 18.5 and 22.0 weeks. In all patients, the amniotic cavity was accessed without hemorrhage. The outcomes are similar to those published previously for laser coagulation. The mean interval from intervention until delivery was 10.5 weeks. All 12 fetuses were live born but four died from complications of extreme prematurity. No maternal complications occurred.

The plug-unplug sequence: an important step to achieve type II pneumocyte maturation in the fetal lamb model.

PURPOSE: The purpose of this study was to test the hypothesis that tracheal obstruction (plugging) in the fetal lamb model leads to a decrease in the absolute number of type II pneumocytes and that reversing the obstruction before birth (unplugging), allows the type II cells to recover while maintaining the beneficial effect on lung growth. METHODS: Nine time-dated pregnant ewes (term, 145 days), carrying 17 fetuses, were used in this surgical trial. The fetuses were divided into three experimental groups: group A underwent plugging at 93 days gestation, followed by unplugging at 110 days; group B animals had tracheal ligation at 93 days and group C consisted of unoperated controls. All fetuses were delivered by cesarean section at 136 days' gestation. The fetal trachea was obstructed with the tracheoscopically placed detachable balloon described by our group. Unplugging was performed by needle puncture of the balloon under tracheoscopic vision. Outcome measurements consisted of lung-to-body-weight ratio (LWBR), lung morphometry (mean terminal bronchial density [MTBD] and linear intercept [Lm]), and assessment of the number of type II pneumocytes. The latter was determined by in situ hybridization to the mRNA of surfactant protein-C, which is exclusively produced by type II cells. Statistics were calculated using a two-tailed unpaired t test and P less than .05 is considered significant. RESULTS: Seventeen animals are included in the results. All of them had lung samples analyzed for lung morphometry, whereas for type II cells analysis, three animals were studied in each group. Morphometric analyses were consistent with pulmonary hyperplasia for group B, whereas group A lungs showed more histological maturity than group C albeit not as marked as group B. In group A, there was a similar number of type II cells to that observed in group C (53.2 +/- 3.9 v 55.9 +/- 4.0, P = .66). However, for group B animals, the number of type II pneumocytes was markedly decreased compared with controls (4.7 +/- 0.1 v 55.9 +/- 4, P = .0003). CONCLUSIONS: The authors conclude that tracheal ligation until birth, although inducing pulmonary hyperplasia, significantly decreases the number of type II pneumocytes in the alveoli. After a temporary 15-day occlusion initiated at 95 days' gestation, there is complete normalization of the density of type II cells. These results bear importance on the duration of PLUG to treat the pulmonary hypoplasia seen in congenital diaphragmatic hernia. Temporary tracheal obstruction now needs to be tested in a hypoplastic lung model.

Tracheoscopic endoluminal plugging using an inflatable device in the fetal lamb model.

OBJECTIVE: Intra-uterine tracheal occlusion has been proposed to reverse pulmonary hypoplasia, an important prognostic factor in congenital diaphragmatic hernia. We aimed to evaluate the feasibility and pulmonary effects of tracheoscopic tracheal obstruction with a detachable balloon. STUDY DESIGN: Fourteen mid-trimester fetuses out of 24 in 13 ewes underwent tracheoscopic balloon obstruction. Ten non-operated fetuses served as controls. Plugging was performed under fiber-tracheoscopy using a detachable balloon. Outcome measures consisted of: total operating time, tracheoscopy time, fetal survival, efficiency of plugging, and pulmonary effects. The Mann-Whitney test and linear regression were used for statistical analysis. RESULTS: Mean operating time and tracheoscopy time were 65+/-12 and 6.6+/-3.9 min, respectively. One intra-operative death occurred in each group. The post-operative mortality was 2/13 for cases and 2/9 for controls. In all 14 fetuses, the trachea was successfully obstructed. In the 11 treated animals born alive, the lung-to-body-weight ratio was 0.060+/-0.01, while in controls it was 0.031+/-0.01 (P = 0.0001). In a subset of six fetuses obstructed for 14-18 days, mean-terminal-bronchial density was 0.95+/-0.59, compared to 2.06+/-0.80 for controls (P = 0.046). CONCLUSIONS: Using fetal tracheoscopy, the trachea can successfully be obstructed with an inflatable balloon. Pulmonary hyperplasia is achieved when the obstruction lasts 2 weeks.

Intrauterine tracheal obstruction, a new treatment for congenital diaphragmatic hernia, decreases amniotic fluid sodium and chloride concentrations in the fetal lamb.

OBJECTIVE: To evaluate the effect of fetal tracheal occlusion on sodium and chloride concentrations in amniotic and tracheal fluid. SUMMARY BACKGROUND DATA: Intrauterine tracheal occlusion has been proposed to reverse pulmonary hypoplasia, an important prognostic factor in congenital diaphragmatic hernia. In early human trials, technical failure of the obstructive device has been reported. METHODS: Eight fetal lambs (gestational age = 95 days) were subjected to fetal tracheoscopy, and amniotic and tracheal fluid samples were taken. In multiple pregnancies (n = 6), amniotic fluid was also sampled from the contralateral amniotic sac and used as a control. Subsequently, endotracheal obstruction, using a detachable balloon, was performed. After 14 days, all fetuses were delivered, and sodium and chloride concentrations in amniotic and tracheal fluid were measured again. Statistical analysis was done using a two-tailed Student's t test, paired or unpaired as appropriate. RESULTS: In controls, between 95 and 109 days gestational age, no significant changes occurred in sodium or chloride concentrations in amniotic or tracheal fluid. After 2 weeks of tracheal obstruction, however, chloride and sodium concentrations in amniotic fluid decreased (chloride = 76.7 mEq/L vs. 107.6 mEq/L, p = 0.0003; sodium = 109.6 mEq/L vs. 125.9 +/- 5.2 mEq/L, p = 0.019). A concomitant increase in chloride and sodium concentration was observed in tracheal fluid (chloride = 145.4 mEq/L vs. 130.0 mEq/L, p = 0.047; sodium = 153.1 mEq/L vs. 142.9 mEq/L, p = 0.051). When comparing groups at 109 days, chloride and sodium concentrations in amniotic fluid were markedly lower in the treated group versus controls (p = 0.0004 and p = 0.05 for chloride and sodium, respectively). CONCLUSION: Complete tracheal occlusion in ovine fetuses results in a significant decrease of amniotic fluid sodium and chloride concentrations.

Tracheoscopic endotracheal occlusion in the ovine model: technique and pulmonary effects.

BACKGROUND/PURPOSE: The purpose of this study was to assess the tracheoscopic placement of a detachable balloon to obstruct the trachea in the fetal lamb model and to study the pulmonary effects 2 weeks later. METHODS: Thirteen pregnant ewes carrying 27 fetuses were used in this trial. Thirteen fetuses underwent endotracheal plugging at a mean gestational age of 95 (90 to 100) days (term, 145). Fourteen nonoperated fetuses served as controls. The intended duration of obstruction was 15 days. Study parameters consisted of operating time, fetal survival, performance of the balloon, and pulmonary changes. RESULTS: Hysterotomy time was 41 +/- 25 minutes and tracheoscopy time was 7.2 +/- 3.4 minutes. There were no intraoperative deaths in this series. Postoperative fatalities occurred in 2 of 13 plugged fetuses and 1 of 14 controls. At completion of the experiment, the balloon was recovered intact in the trachea of 12 of 13 (92.3%) fetuses. The lung weight/body weight ratio was 76 +/- 16 mg/kg for plugged animals, while in controls it was 34 +/- 8 mg/kg (P = .0001). The lung volume/body weight ratio was 101 +/- 17 mL/kg in plugged fetuses, compared with 47 +/- 4 mL/kg for controls (P = .0002). Mean-terminal-bronchial-density was 0.937 +/- 0.303 for plugged animals, compared with 1.911 +/- 0.441 for controls (P = .0002). Mean linear intercept was 60.9 +/- 5.2 microm in treated fetuses, and 46.3 +/- 5.8 microm for controls (P = .0004). CONCLUSIONS: Fetal endotracheal occlusion, using a tracheoscopically placed detachable balloon, is reliable, and results in pulmonary hyperplasia after 2 weeks of obstruction. This technique may be beneficial in treating the pulmonary hypoplasia seen in congenital diaphragmatic hernia. Further studies using this balloon device are now required to corroborate these findings.