Perinatal management of congenital diaphragmatic hernia

Congenital diaphragmatic hernia: defect size correlates with developmental defect

PURPOSE

The aim of our study was to elucidate if the defect size reflects the magnitude of the developmental defect in patients with CDH.

METHODS

All patients recorded in the CDH Study Group registry between January 1, 2007, and December 31, 2010, and with defect classification were included in the study. They were divided according to defect size (A-D) and compared for: gestational age (GA), birth weight (BW), number of abnormal organ systems, prevalence of associated anomalies, cardiovascular malformations (CVM), chromosomal anomalies, liver in the chest, and hernia sac.

RESULTS

A total of 1350 of 1778 patients had defect classification: 173 A, 557 B, 438 C, and 182 D. Mortality rate was 0.6%, 5.3%, 22.6%, and 45.6% in group A, B, C, and D, respectively, (p<0.0001; p for trend <0.0001). GA, BW, prevalence of associated anomalies, particularly CVM, number of abnormal organ systems, and prevalence of sac were significantly different between the groups, with a significant reduction of GA, BW, and prevalence of sac. There was an increase in prevalence of associated anomalies, liver in the chest, and number of abnormal systems as the defect size increased.

CONCLUSION

Defect size is directly correlated with mortality rate, prevalence of other anomalies (particularly CVM), and number of abnormal systems, and inversely with GA, BW, and prevalence of hernia sac. The defect size may be a marker for the magnitude of developmental abnormality, thereby explaining its relationship with the outcome.

Long term follow-up in high-risk congenital diaphragmatic hernia survivors: patching the diaphragm affects the outcome

BACKGROUND/PURPOSE

The increased survival rate reached in infants with congenital diaphragmatic hernia (CDH) has shown a concomitant increase in late morbidity. A recent report from CDH Study Group showed that dimension of diaphragmatic defect is the only independent risk factor of mortality. However, the influence of defect size on late morbidity is still controversial. The aim of the study was to evaluate the influence of patch repair (proxy of diaphragmatic defects size) on midterm morbidity.

METHODS

All high-risk (prenatal diagnosis and/or respiratory symptoms within 6 hours of life) CDH survivors treated at our institution from 2004 to 2008 were followed up in a multidisciplinary outpatient clinic as part of a longitudinal prospective study. Auxological, gastroesophageal, pulmonary, and orthopedic evaluations were performed at 6, 12, and 24 months of age. Patient outcomes were compared with respect to +/- patch repair.

RESULTS

Of 70 survivors, 61 (87%) were enrolled and prospectively evaluated in follow-up. Poorer auxological outcome, increased rate of gastroesophageal reflux, and altered pulmonary function test were observed during follow-up.

CONCLUSIONS

Patch repair correlates with higher pulmonary, auxological, and gastroesophageal morbidity without increasing chest wall deformities at long-term follow-up.

How useful is the lung-to-head ratio in predicting outcome in the fetus with congenital diaphragmatic hernia? A systematic review and meta-analysis

OBJECTIVE

Fetal surgery to improve lung growth comprises tracheal occlusion in selected 'high-risk' fetuses with congenital diaphragmatic hernia (CDH). Sonographically measured fetal lung-to-head ratio (LHR) is utilized to recruit candidates for fetal surgery. This study provides a meta-analysis of the evidence regarding the prognostic use of lung-to-head ratio measurements in fetal CDH.

METHODS

MEDLINE, SCOPUS and ISI PROCEEDINGS databases were searched for MeSH terms: lung, head, hernia and ratio. References in retrieved studies were also searched. Studies were categorized as follows: Phase I studies measured normal fetal LHR; Phase II studies compared fetal LHR in CDH survivors and non-survivors (if LHR informed therapy decisions or LHR was not measured during the window for intervention (< 32 weeks' gestation), studies were excluded); Phase III studies used LHR to guide selection for fetal surgery (non-randomized trials were excluded); Phase IV studies measured CDH survival before and after LHR application in clinical practice.

RESULTS

The one Phase I study showed that LHR varied substantially with gestation and technique. No complete studies met the selection criteria for Phase II: meta-analysis of subgroups revealed similar LHR in CDH survivors and non-survivors. A single Phase III study revealed no benefit for LHR-directed fetal surgery. No Phase IV studies were identified.

CONCLUSION

The prognostic use of LHR in fetal CDH entered clinical practice prior to publication of robust normal data and is not supported by current evidence. Application of a structured approach to any 'new' prognostic test could improve its validity and clinical application.

Lung volumes and distribution of ventilation in survivors to congenital diaphragmatic hernia (CDH) during infancy

The assessment of lung volumes, particularly functional residual capacity (FRC), is crucial for understanding lung development during infancy in CDH patients.

AIM

To evaluate changes in lung function during infancy in subjects with CDH treated with a "gentle ventilation" technique and delayed surgery strategy in the neonatal period.

METHODS

13 CDH infants were studied twice and compared with a population of 28 healthy infants (HI). Tidal-Volume (Vt), respiratory rate (RR) and time to peak expiratory flow/expiratory time ratio (tPTEF/Te) were measured with an ultrasonic flow meter; Compliance (Crs) and Resistance (Rrs) of the respiratory system were studied with the single occlusion technique; FRC and Lung Clearance Index (LCI), were assessed with the sulfur hexafluoride (SF6) wash-in/wash-out technique. The differences between the first (T1) and second (T2) measurement in the CDH group were assessed by the Student's t-test for paired values. For each set of measurement (T1 and T2) the values were compared with HI by Student's t-test.

RESULTS

Mean age at test was 7.5 +/- 5.2 months for HI, 4.5 +/- 2.5 at T1 and 11.9 +/- 4.5 months at T2 for CDH infants. At T1 there were no significant differences between CDH infants and HI in Vt, Crs, and FRC, while tPTEF/te ratio was lower and RR, Rrs, and LCI were higher in CDH patients than in HI. At T2 Vt, Crs, and FRC remained normal in CDH patients as well as RR that, at this time was not different between CDH and healthy infants; tPTEF/te remained below and Rrs and LCI remained above normal ranges, indicating a persistent impairment in lower airways patency.

CONCLUSIONS

Lung function in infants with severe CDH is characterized by a persistent impairment in airways patency and significant inhomogeneity of ventilation, suggesting a peripheral bronchial obstruction even if the other lung function tests are within normal ranges.

Surgical management of neonates with congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is one of the most challenging and complex pediatric abnormalities to manage, both medically and surgically. The care of these neonates has seen significant evolution, from previous aggressive ventilation and emergent operation to current permissive hypercapnea, physiologic stabilization, and elective surgical repair, all in less than two decades. These changes have led to many centers reporting survival rates near 80%, a dramatic improvement from the 50% survival reported in the 1970s. This review covers the current principles guiding the surgical management of CDH in the neonate, including preoperative stabilization, operative timing, extracorporeal membrane oxygenation, surgical approach, and management of recurrence. Although many clinical challenges remain, multi-institutional collaboration and ongoing research efforts will hopefully improve the clinical care of these patients.

Genome-wide oligonucleotide-based array comparative genome hybridization analysis of non-isolated congenital diaphragmatic hernia

Non-isolated congenital diaphragmatic hernia (CDH+) is a severe birth defect that is often caused by de novo chromosomal anomalies. In this report, we use genome-wide oligonucleotide-based array comparative genome hybridization (aCGH) followed by rapid real-time quantitative PCR analysis to identify, confirm and map chromosomal anomalies in a cohort of 26 CDH+ patients. One hundred and five putative copy number changes were identified by aCGH in our cohort of CDH+ patients. Sixty-one of these changes (58%) had been previously described in normal controls. Twenty of the remaining 44 changes (45%) were confirmed by quantitative real-time PCR or standard cytogenetic techniques. These changes included de novo chromosomal abnormalities in five of the 26 patients (19%), two of whom had previously normal G-banded chromosome analyses. Data from these patients provide evidence for the existence of CDH-related genes on chromosomes 2q37, 6p22-25 and 14q, and refine the CDH minimal deleted region on 15q26 to an interval that contains COUP-TFII and only eight other known genes. Although COUP-TFII is likely to play a role in the development of CDH in patients with 15q26 deletions, we did not find COUP-TFII mutations in 73 CDH samples. We conclude that the combination of oligonucleotide-based aCGH and quantitative real-time PCR is an effective method of identifying, confirming and mapping clinically relevant copy number changes in patients with CDH+. This method is more sensitive than G-banded chromosome analysis and may find wide application in screening patients with congenital anomalies.

[The pediatric surgeon's role in intensive care]

In contrast to adult surgery, pediatric surgery today is particularly dependent on multidisciplinary cooperation, especially with pediatricians, neonatologists, and pediatric anesthesiologists. This is particularly important in intensive care. Pediatric surgery is not able to manage this challenge on its own because of small numbers of intensive care patients, small staff with few intensive care specialists, and little general interest. The pediatric surgeon's role in interdisciplinary intensive care is to ensure optimal treatment for his patients by helpful cooperation, commitment, and readiness to take on responsibility, together with his own irreplaceable expertise.