A risk-adjusted study of outcome and resource utilization for congenital diaphragmatic hernia

Purpose

Perinatal care of infants with congenital diaphragmatic hernia (CDH) is nonstandardized and costly. We examined a risk-adjusted cohort of patients with CDH and hypothesized that (1) among CDH survivors, the cost of the birth admission would be proportional to illness severity, and (2) this cost would be significantly higher compared with a matched non-CDH cohort.

Methods

A retrospective review of costs and outcomes for all patients with CDH admitted to British Columbia Children's Hospital between 1999 and 2003 was performed. Risk grouping of patients with CDH using a validated admission severity score (Score for Neonatal Acute Physiology-version II [SNAP-II]) was conducted, enabling comparison among infants surviving to discharge. Hospital costs were also compared with a contemporaneous, non-CDH cohort matched for birth weight and SNAP-II.

Results

Thirty-two infants with CDH were included, of who 5 required extracorporeal membrane oxygenation. Twenty-three (72%) infants survived to discharge, with an average length of stay of 46 days. Average cost per survivor to discharge was $54,102 (vs $13,722 for the non-CDH cohort; P < .05). After SNAP-II stratification of survivors into low-, moderate-, and high-risk groups, a significant cost difference was noted between the moderate- and low-risk and high- and low-risk groups, respectively.

Conclusions

Infants born with CDH require costly care and can be expected to consume disproportionate resources. Admission SNAP-II score correlates with total cost to discharge. Risk stratification and cost comparison of larger CDH populations may allow identification of cost-efficient treatment strategies.     

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.     

Patterns of cerebral injury in a series of infants with congenital diaphragmatic hernia utilizing magnetic resonance imaging

Background

Congenital diaphragmatic hernia (CDH) is a condition with significant mortality and respiratory morbidity. Long-term neurodevelopmental outcome is not yet well documented.

Methods

The authors examined all cases of CDH at their institution over a 12-month period and performed magnetic resonance imaging (MRI) of the brain postoperatively.

Results

Eight of 10 patients survived to have an MR brain scan. All 8 patients had cerebral injury detected on MRI, with a predominance of white matter and deep nuclear gray matter injury.

Conclusions

Cerebral injury detected with MRI is common in infants with congenital diaphragmatic hernia. The long-term significance of these MRI abnormalities is unknown, although the need for good long-term neurodevelopmental follow-up of infants with CDH is highlighted.     

Dynamic tracheal occlusion improves lung morphometrics and function in the fetal lamb model of congenital diaphragmatic hernia

Background

Congenital diaphragmatic hernia (CDH) is associated with significant neonatal morbidity and mortality. Although prenatal complete tracheal occlusion (cTO) causes hypoplastic CDH lungs to enlarge, improved lung function has not been demonstrated. Furthermore, cTO interferes with the dynamic pressure change and fluid flow associated with fetal breathing.

Purpose

The purpose of the study was to assess a novel dynamic tracheal occlusion (dTO) device that preserves pressure changes and fluid flow.

Methods

In this pilot study, CDH was created in fetal lambs at 65 days of gestational age (GA). At 110 days GA, a cTO device (n = 3) or a dTO device (n = 4) was placed in the fetal trachea. At 135 days GA, lambs were delivered and resuscitated. Unoperated lamb co-twins (n = 5), sham thoracotomy lambs (n = 2), and untreated CDH lambs (n = 3) served as controls.

Results

Tracheal opening pressure, lung volume, lung fluid total protein, and phospholipid were significantly higher in the cTO group than in the dTO and unoperated control groups. Maximal oxygenation and lung compliance were significantly lower in the cTO group when compared with the unoperated control and dTO groups.

Conclusion

Preliminary results suggest that in the fetal lamb CDH model, dTO restores normal lung morphometrics and function, whereas cTO leads to enlarged but less functional lungs.     

Active surveillance of small renal masses: progression patterns of early stage kidney cancer

Background

Most early stage kidney cancers are renal cell carcinomas (RCCs), and most are diagnosed incidentally by imaging as small renal masses (SRMs). Indirect evidence suggests that most small RCCs grow slowly and rarely metastasize.

Objective

To determine the progression and growth rates for newly diagnosed SRMs stratified by needle core biopsy pathology.

Design, setting, and participants

A multicenter prospective phase 2 clinical trial of active surveillance of 209 SRMs in 178 elderly and/or infirm patients was conducted from 2004 until 2009 with treatment delayed until progression.

Intervention

Patients underwent serial imaging and needle core biopsies.

Measurements

We measured rates of change in tumor diameter (growth measured by imaging) and progression to ≥4 cm, doubling of tumor volume, or metastasis with histology on biopsy.

Results and limitations

Local progression occurred in 25 patients (12%), plus 2 progressed with metastases (1.1%). Of the 178 subjects with 209 SRMs, 127 with 151 SRMs had > 12 mo of follow-up with two or more images, with a mean follow-up of 28 mo. Their tumor diameters increased by an average of 0.13 cm/yr. Needle core biopsy in 101 SRMs demonstrated that the presence of RCC did not significantly change growth rate. Limitations included no central review of imaging and pathology and a short follow-up.

Conclusions

This is the first SRM active surveillance study to correlate growth with histology prospectively. In the first 2 yr, the rate of local progression to higher stage is low, and metastases are rare. SRMs appear to grow very slowly, even if biopsy proven to be RCC. Many patients with SRMs can therefore be initially managed conservatively with serial imaging, avoiding the morbidity of surgical or ablative treatment.     

Survival rate in congenital diaphragmatic hernia: the experience of the Canadian Neonatal Network

Background/purpose

The Canadian Neonatal Network prospectively collects data from 17 pediatric hospitals accounting for 75% of all neonatal intensive care unit beds nationwide. The purpose of this study was to (1) analyze the database to compare actual survival rates of neonates with congenital diaphragmatic hernia (CDH) to predicted outcomes and (2) assess whether institutional CDH volume was associated with improved survival rate.

Methods

Actual survival rates for CDH patients born during a 22-month period were determined from the registry. Predicted survival rates were calculated using the CDH Study Group logistical regression equation. Actual survival rate was compared with predicted using χ² analysis. Survival rates were stratified by institutional CDH volume and compared using binomial analysis. P value of less than .05 was deemed statistically significant.

Results

Of approximately 20,500 neonatal admissions, 88 cases of CDH were recorded. Seventy-three of 88 (83%) neonates with CDH survived to discharge, whereas the predicted survival rate was 62% (P < .001). Three centers were considered “high-volume” centers with at least 12 CDH diagnoses, and 11 were considered “low-volume” centers. Actual CDH survival was significantly greater at high-versus low-volume centers (90% v 77%; P < .01).

Conclusions

From these prospective data, survival rates of Canadian neonates with CDH are significantly better than predicted by the CDH Study Group equation. Further, high-volume centers in Canada have a significantly higher CDH survival rate than low-volume centers.     

The hidden mortality of congenital diaphragmatic hernia: a 20-year review

Aims

The true mortality associated with congenital diaphragmatic hernia (CDH) is hidden because survival analyses do not include fetuses with CDH. A retrospective review of all postmortems (PMs) with a diagnosis of CDH over a 20-year period was carried out to highlight this hidden mortality and also measure the nature and number of associated anomalies.

Methods

Postmortem case record details were reviewed for the period January 1986 to December 2005. Data were collected on live birth, stillbirth, therapeutic abortion, and spontaneous abortion.

Results

There was a decline in the annual number of PMs during the period of the study. The median for the four 5-year intervals being 609 (570-657), 528 (488-565), 515 (413-537), and 373 (357-388). A total of 130 PMs were identified, which included a diagnosis of CDH; 97 (75%) were left sided, 22 (17%) were right sided, and 11 (8%) were bilateral. There were 69 live births, 46 therapeutic abortions, 10 stillbirths, and 5 intrauterine deaths; 22% were right sided/bilateral in the live and therapeutic abortion groups, whereas 53% were right sided/bilateral in the latter 2 groups. Of 130, 82 (63%) had major associated anomalies, and 50% of these had at least 1 further major anomaly. The commonest categories of anomalies were cardiac (30), gastrointestinal/abdominal wall defect (28), and neural tube defects (25).

Conclusions

The true incidence of CDH is considerably higher than that seen in neonatal surgical practice. The decline in number of PMs in our region will exacerbate the underestimation of the true incidence. There is a higher incidence of right-sided/bilateral hernias and more than one major anomaly in those who die in utero.     

Outcomes of multigestational pregnancies affected by congenital diaphragmatic hernia

Background/purpose

The prognosis for multiple vs singleton pregnancies affected by congenital diaphragmatic hernia (CDH) is not known. To improve the counseling of families with multiple gestation pregnancies complicated by CDH, we examined outcomes of a consecutive series of CDH cases occurring in multiple gestation pregnancy referrals.

Methods

Clinical characteristics and morbidity and mortality data were gathered for a consecutive series of infants with CDH from 16 multiple gestation pregnancies. Outcomes were compared to a cohort of 91 patients with CDH from singleton pregnancies. Multivariate regression was also used in an attempt to determine whether multiple gestation pregnancy was independently predictive of subsequent long-term adverse outcomes.

Results

Four pregnancies were lost to follow-up, and 1 underwent selective reduction. Overall mortality for live-born multiple gestation fetuses affected by CDH was 30% and was 8% for unaffected siblings. No pregnancy was concordant. Clinical features were not different between the case series and control infants, except median gestational age at delivery, which was significantly lower for the multigestational infants (34 [range, 32-36] vs 38 [range, 28-41] weeks) (P = .02). Long-term morbidity was comparable between cases and controls.

Conclusions

In terms of mortality, outcomes of multigestational pregnancies affected by CDH are no worse than for CDH pregnancies in general. Long-term risk may depend more on CDH severity rather than the presence of multiple fetuses.     

Early experience with minimally invasive repair of congenital diaphragmatic hernias: results and lessons learned

Background:

Minimally invasive surgery (MIS) for the repair of congenital diaphragmatic hernias (CDH) had been described. This report reviews the authors’ experience with MIS repairs of CDH and discusses the technical development of this approach.

Methods:

From 1999 until now, the authors collected data on children who underwent an MIS approach for CDH repair.

Results:

Seventeen children (11 Morgagni and 7 Bochdalek) had undergone an attempt at MIS repair. All Morgagni defects were treated successfully using laparoscopy (mean age, 28 ± 31 months). Mean follow-up was 22 ± 9 months. There was 1 recurrence. Four children with Bochdalek CDH were treated as newborns (range, 3 to 21 days), and 3 had operations later (4, 11, and 32 months). The first repair was attempted initially transabdominally and was converted to a thoracoscopic approach. The rest of the Bochdalek repairs were performed thoracoscopically. Bochdalek repairs via MIS were successful in 3 children (2 older children and 1 neonate). No child had pulmonary hypertension. Two of the 3 Bochdalek patients did well postoperatively (follow-up, 18 +/− 7 months); the last patient experienced recurrence 11 months after repair.

Conclusions:

MIS for CDH is ideal for Morgagni defects. It should be considered for nonnewborns with a Bochdalek CDH. The MIS approach for a newborn with a CDH cannot be recommended because of the high failure rate and frequent rise in Pco₂ levels.     

Salvaging the severe congenital diaphragmatic hernia patient: is a silo the solution?

Background

Infants with severe congenital diaphragmatic hernia (CDH) requiring extracorporeal membrane oxygenation (ECMO) have a high morbidity and mortality. We hypothesized that placement of an abdominal wall silo and staged abdominal wall closure may reduce problems associated with decreased abdominal domain in CDH.

Methods

We performed a retrospective review and identified 7 CDH patients requiring ECMO who had a silastic abdominal wall silo between 2003 and 2006. Variables analyzed included survival, ECMO duration, duration of silo, time to discharge, and long-term outcome.

Results

Predicted mean survival for the entire cohort using the published CDH Study Group equation was 47% (range, 9%-86%). All 7 patients (100%) survived. Extracorporeal membrane oxygenation duration averaged 15 days (range, 5-19 days). Four of the patients (58%) were repaired with a silo on ECMO, and 3 (42%) had their repair after ECMO. The abdominal wall defect was closed at a mean of 21 days (range, 4-41 days). Hospital stay after silo placement averaged 54 days (range, 20-170 days) with no infections or wound complications.

Conclusions

Abdominal wall silo placement in infants with CDH requiring ECMO appears to be an effective strategy for decreased abdominal domain. Further studies are warranted to determine the efficacy of such a strategy for these high-risk CDH patients.     

Predicting the need for fundoplication at the time of congenital diaphragmatic hernia repair

Purpose

This study was conducted to examine the preoperative factors predictive of subsequent intervention for gastroesophageal reflux (GER) in children with congenital diaphragmatic hernia (CDH).

Methods

We conducted a retrospective cohort study on children who underwent repair of a CDH between January 1, 1995, and December 31, 2002 with follow-up continuing to September 1, 2005. Excluded in the study were children who died during their first admission, or who underwent fundoplication at the time of CDH repair. Univariate and multivariate logistic regressions were performed to examine preoperative factors predictive of subsequent intervention (fundoplication or gastrojejunal tube placement).

Results

Of 86 children, 13 underwent intervention (fundoplication, 10; gastrojejunal tube, 3) for GER. Univariate predictors included the following: right-sided CDH, use of nonconventional ventilation, liver within the chest, and patch closure of the CDH. However, only liver within the chest and patch closure of the CDH were significant predictors in a multiple variable analysis. The positive and negative predictive values of the multivariate model were 69.2% and 87.7%, respectively.

Conclusions

Infants with CDH who have liver within the chest or require patch closure of their hernia are at increased risk for subsequent intervention for GER. These children may represent a subpopulation that would benefit from fundoplication at the time of CDH repair.     

First 24-h SNAP-II score and highest PaCO2 predict the need for ECMO in congenital diaphragmatic hernia

Background/Purpose

Early clinical predictors for the use of ECMO in patients with congenital diaphragmatic hernia (CDH) are lacking. We sought to evaluate the first 24-h SNAP-II score and highest PaCO₂ as predictors of ECMO support and in-hospital mortality in neonates with CDH.

Methods

Retrospective review of 47 consecutive neonates with CDH admitted to our institution from January 2007 to December 2010 was performed. Covariates of ECMO use including SNAP-II score and highest PaCO₂ within the first 24 h of NICU admission were evaluated.

Results

Of the 47 infants in this study, 24 patients were supported with ECMO. The ECMO group had a higher incidence of pulmonary hypertension, higher PaCO₂, and higher 24-h SNAP-II scores. Only the SNAP-II score and not highest PaCO₂ predicted mortality following multivariate adjustment.

Conclusions

The first 24-h SNAP-II score and highest PaCO₂ may provide some prognostic value in identifying neonates who undergo ECMO support; however neither measure was independently associated with the use of therapy. Only the SNAP-II score was associated with in-hospital mortality following multivariate adjustment. Additional study is needed to validate these results in a larger data set.     

Absolute vs relative improvements in congenital diaphragmatic hernia survival: what happened to “hidden mortality”

Purpose

The aim of this study is to determine if there has been a true, absolute, or apparent relative increase in congenital diaphragmatic hernia (CDH) survival for the last 2 decades.

Method

All neonatal Bochdalek CDH patients admitted to an Ontario pediatric surgical hospital during the period when significant improvements in CDH survival was reported (from January 1, 1992, to December 31, 1999) were analyzed. Patient characteristics were assessed for CDH population homogeneity and differences between institutional and vital statistics-based population survival outcomes. SAS 9.1 (SAS Institute, Cary, NC) was used for analysis.

Result

Of 198 cohorts, demographic parameters including birth weight, gestational age, Apgar scores, sex, and associated congenital anomalies did not change significantly. Preoperative survival was 149 (75.2%) of 198, whereas postoperative survival was 133 (89.3%) of 149, and overall institutional survival was 133 (67.2%) of 198. Comparison of institution and population-based mortality (n = 65 vs 96) during the period yielded 32% of CDH deaths unaccounted for by institutions. Yearly analysis of hidden mortality consistently showed a significantly lower mortality in institution-based reporting than population.

Conclusion

A hidden mortality exists for institutionally reported CDH survival rates. Careful interpretation of research findings and more comprehensive population-based tools are needed for reliable counseling and evaluation of current and future treatments.     

Early repair of congenital diaphragmatic hernia on extracorporeal membrane oxygenation

Background

Timing of repair of congenital diaphragmatic hernia (CDH) in babies that require stabilization on extracorporeal membrane oxygenation (ECMO) remains controversial. Although many centers delay operation until physiologic stabilization has occurred or ECMO is no longer needed, we repair soon after ECMO has been initiated. The purpose of this study is to determine if our approach has achieved acceptable morbidity and mortality.

Methods

Charts of live-born babies with CDH treated at our institution between 1993 and 2007 were retrospectively reviewed. Data were then compared with The Congenital Diaphragmatic Hernia Study Group and Extracorporeal Life Support Organization registries.

Results

Forty-eight (39%) patients required ECMO Thirty-four of these 48 neonates were cannulated before operative repair. Venoarterial ECMO was used exclusively. The mean (SD) time of repair from cannulation was 55 (21) hours. Survival for this subset of patients was 71%. Three patients (8.8%) who underwent repair on ECMO experienced surgical site hemorrhage that required intervention.

Conclusion

Early repair of CDH in neonates on ECMO can be accomplished with acceptable rates of morbidity and mortality.     

Profiling of nuclear extract proteins from human neuroblastoma cell lines: the search for fingerprints

Purpose

Neuroblastoma (NB) commonly presents with advanced disease at diagnosis and is associated with poor survival. If identified early, however, survival is improved suggesting a benefit of early detection. The authors have used proteomics technology in an attempt to identify novel markers that permit early detection of NB and characterize its molecular makeup.

Methods

Three different human NB cell lines SK-N-AS, SK-N-DZ, and SK-N-FI were subjected to series of biochemical fractionation steps to extract nuclear proteins. These proteins were analyzed for differential expression by 2-dimensional polyacrylamide gel electrophoresis. Polypeptides of interest were subsequently identified by liquid chromatography-linked tandem mass spectrometry.

Results

Multiple proteins were identified in these human NB cell lines including SET (a ubiquitous nuclear protein), stathmin (a cytosolic signal transduction protein), and grp94 (a heat shock protein). SET is a putative oncogene associated with the chromosomal translocation (6;9) leading to acute undifferentiated leukemia. Stathmin is an oncogene found in greater abundance in leukemic cells compared to nonleukemic cells. A total of 94-kDa glucose-regulated protein has been shown to be protective in human breast cancer cells in vitro and related with the occurrence, differentiation, and progression of human lung cancer. The first protein has not been previously associated with NB.

Conclusions

The identification of these 3 previously unrecognized cancer-related potential biomarkers in human NB cell lines may prove useful in developing diagnostic tests. The proteomic methodology of 2-dimensional polyacrylamide gel electrophoresis/mass spectrometry also provides an improved opportunity to understand the natural history of NB and develop novel chemotherapeutic agents for this prevalent childhood malignancy with a dismal outcome.     

Percent predicted lung volumes as measured on fetal magnetic resonance imaging: a useful biometric parameter for risk stratification in congenital diaphragmatic hernia

Purpose

This study was aimed at determining whether a new method of analyzing lung volumes on fetal magnetic resonance (MR) imaging could be used to predict the degree of pulmonary compromise in congenital diaphragmatic hernia (CDH).

Methods

Seventeen fetuses with CDH were prospectively evaluated by MR. Lung volumes were measured using an established technique and expressed as a percentage of the predicted lung volume (PPLV). Predicted lung volume was determined by subtracting measured mediastinal volume from total measured thoracic volume. The PPLV was correlated with postnatal outcomes. Statistical analyses were performed using the Mann-Whitney, Spearman correlation, or Fisher exact tests (P < .05).

Results

Of the 14 liveborn patients, the PPLV was 20.3±10.4 (gestational age at MR, 22.3 ± 5.7 weeks). The PPLV was significantly associated with extracorporeal membrane oxygenation (ECMO) use, hospital length of stay, and survival. All patients with a PPLV of less than 15 required prolonged ECMO support and had a 40% survival rate. In contrast, only 11% of patients with a PPLV of greater than 15 required ECMO, and survival was 100%.

Conclusion

The PPLV as measured by fetal MR imaging can accurately predict disease severity in CDH. A value of less than 15 is associated with a significantly higher risk for prolonged support and/or death, despite aggressive postnatal management.     

Fetoscopic temporary tracheal occlusion for congenital diaphragmatic hernia: prelude to a randomized,controlled trial

Objective

As previously reported, high postnatal mortality seen in fetuses with congenital diaphragmatic hernia (CDH) with liver herniation and low lung-to-head ratio (LHR) appears to be improved in fetuses who undergo fetoscopic temporary tracheal occlusion (TO). To test whether further evolution of this technique produces results that justify a randomized controlled trial comparing prenatal intervention to postnatal care, the authors analyzed 11 additional cases and the cumulative experience with 19 cases.

Methods

The authors analyzed retrospectively the outcome of 11 new and 8 previously reported cases of fetoscopic temporary tracheal occlusion. Various factors were studied including maternal morbidity, antenatal outcome, physiologic lung response, and neonatal course.

Results

Temporary TO can be accomplished using 3 5-mm radially expanding uterine ports without hysterotomy. Obstetric morbidity included mild pulmonary edema in 6 cases, chorioamniotic separation and premature rupture of membranes in 12 patients, and preterm labor and delivery in all patients. Thirteen of 19 (68%) neonates survived for 90 days after delivery; one died in utero, and 5 died after birth. Late mortality included one death caused by sepsis and 2 by complications associated with tracheostomies. Morbidity from gastroesophageal reflux requiring Nissen fundoplication, tracheal injury requiring repair or tracheostomy, and recurrent hernias after diaphragmatic repair were characteristic in longterm survivors.

Conclusions

Fetoscopic temporary TO may improve outcome in poor-prognosis fetuses with CDH. However, complications related to tracheal dissection, premature delivery and late morbidity are significant. This experience has led to simpler techniques for fetoscopic tracheal occlusion and to an National Institutes of Health-sponsored randomized controlled trial comparing fetoscopic tracheal occlusion with optimal postnatal care.     

Late-presenting congenital diaphragmatic hernia

Background

Late-presenting congenital diaphragmatic hernia (CDH) is a rare subset of CDH, most of the information derived from small series or case reports. The aim of this study was to document the clinical manifestations of late-presenting CDH using a large multicenter database.

Methods

Information about late-presenting CDH (diagnosed at later than 30 days of age) was identified from the database of the CDH Study Group (3098 cases collected during 1995-2004) and reviewed retrospectively.

Results

Seventy-nine cases (2.6%) from 30 centers met the inclusion criteria. Seven cases had a Morgagni hernia. There were 50 males (65%) and 27 females (35%). The mean age at diagnosis was 372 days (32 days to 15 years). Major associated anomalies (10 cardiac and 7 chromosomal abnormalities) were identified in 12 cases (15%). Presenting symptoms were respiratory in 20 (43%), gastrointestinal in 15 (33%), both in 6 (13%), and none (asymptomatic) in 5 (11%). The hernia was left-sided in 53 (69%), right-sided in 21 (27%), and central or bilateral in 3 (4%). Patients with gastrointestinal symptoms invariably had left-sided hernias (n = 19), whereas patients with respiratory symptoms (n = 24) seemed equally likely to have right- or left-sided lesions. A primary repair without patch was done in all cases with 100% survival.

Conclusions

Presenting symptoms of late-onset CDH can be respiratory or gastrointestinal, but presentation with gastrointestinal problems was more common in left-sided hernias, whereas respiratory symptoms predominated in right-sided lesions. The prognosis is excellent once the correct diagnosis is made.     

Prenatal treatment with retinoic acid promotes pulmonary alveologenesis in the nitrofen model of congenital diaphragmatic hernia

Background/Purpose

Severe pulmonary hypoplasia remains the main cause of the high mortality in newborn infants with congenital diaphragmatic hernia (CDH). Retinoids are a family of molecules derived from vitamin A, which play an important role in lung development. We hypothesized that retinoids promote alveologenesis at the end of gestation and therefore designed this study to investigate the effects of retinoid acid on nitrofen-induced hypoplastic lungs in CDH.

Methods

Pregnant rats were exposed to either olive oil or 100 mg nitrofen on day 9 of gestation. Retinoic acid 5 mg/kg was given intraperitoneally on days 18, 19, and 20 of gestation and fetuses were recovered on day 21. We had 4 study groups: control (n = 24), control + retinoic acid (n = 22), CDH (n = 24), and CDH + retinoic acid (n = 19). Lungs from the 4 study groups were fixed, and the following stereological measurements were performed on vertical random sections: total lung volume, volume density of airspaces, volume density of air walls, gas exchange surface area, alveolar volume, and total number of alveoli per lung. Total DNA content of each lung was measured using a spectrophotometer.

Results

Total lung volume increased in CDH lungs after the addition of retinoic acid but remained the same in the control group. Gas exchange surface area was larger in CDH lungs after the addition of retinoic acid but remained unchanged in the control group. The total number of alveoli per lung was higher after the addition of retinoic acid. Total DNA content as well as total DNA content-lung weight ratio of the left lung increased significantly in the CDH group after the addition of retinoic acid compared with CDH without retinoic acid.

Conclusions

Our results demonstrate that prenatal treatment with retinoic acid stimulates alveologenesis in hypoplastic lungs in CDH.