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.     

Right-sided congenital diaphragmatic hernia: high utilization of extracorporeal membrane oxygenation and high survival

Purpose

The purpose of the study was to assess the treatment strategies and outcome of right-sided congenital diaphragmatic hernia (R-CDH), particularly extracorporeal membrane oxygenation (ECMO).

Methods

We reviewed the cases of 42 patients treated for R-CDH at our institution from 1991 to 2006. We gathered demographic information, documented ECMO use and the type of surgical repair, and compared outcomes with predicted survival as calculated by the CDH Study Group's equation.

Results

Of the 35 patients included in our statistical analysis (7 were excluded), 12 (34%) were born at our institution, all of whom were prenatally diagnosed with R-CDH. Nineteen patients (54%) required ECMO therapy. Extracorporeal membrane oxygenation was initiated after repair of the R-CDH in 2 patients (11%). Of those patients who went on ECMO before repair, 4 patients (21%) were repaired on ECMO, 9 patients (47%) underwent repair after ECMO, and 4 patients (21%) underwent ECMO but died before their R-CDH could be repaired. Primary repair of the diaphragm was possible in 15 cases (56%), and primary closure of the abdominal incision was possible in 15 of the 23 open repairs (65%). The mean predicted survival for all 35 patients was 63%, whereas 28 (80%) actually survived. Logistic regression showed a significant association between the presence of cardiac defects and mortality (odds ratio = 0.008, P = .014).

Conclusions

Our data suggest that patients with R-CDH have high ECMO utilization and may experience greater relative benefit from ECMO as evidenced by their higher-than-expected overall survival. Extracorporeal membrane oxygenation may be found to have a distinctive role in managing R-CDH. More high-powered series are needed to elucidate differences between R-CDH and left-sided CDH that may dictate alternate forms of management.     

Venovenous versus venoarterial extracorporeal membrane oxygenation in congenital diaphragmatic hernia

Background: Extracorporeal membrane oxygenation (ECMO) has a significant role as a final rescue modality in severe respiratory failure of the newborn with congenital diaphragmatic hernia (CDH). The objective of this study was to compare the efficiency of venovenous (VV) versus venoarterial (VA) ECMO in newborns with CDH.Methods: A retrospective report of 11 years experience (1990 through 2001) of a single center, comparing VV and VA ECMO is given. VV ECMO was the preferred rescue modality for respiratory failure unresponsive to maximal medical therapy. Only when the placement of a VV ECMO 14F catheter was not possible, VA ECMO was used. Forty-six patients met ECMO criteria; 26 were treated with VV ECMO and 19 with VA ECMO. One patient underwent conversion from VV to VA ECMO.Results: Before ECMO, there was no difference between VV and VA ECMO patients in mean oxygenation index (83 v 83), mean airway pressure (18.4 v 18.9 cm H₂O), ECMO cannulation age (28 v 20 hours), or in the percentage of patients who needed dopamine and dobutamine (100% v 100%). From November 1994, nitric oxide (NO) was available; before ECMO, 11 of 14 (79%) VV ECMO patients received NO versus 9 of 10 (90%) patients in the VA group. VV ECMO patients were larger (3.34 v 2.77 kg; P < .05) and of advanced gestational age (39.0 v 36.9 wk; P < .05) compared with VA ECMO patients. There was no significant difference between VV and VA ECMO patients in survival rate (18 of 26, 69% v 13 of 19, 68%), ECMO duration (152 v 150 hours), time of extubation (32.0 v 33.5 days), age at discharge (73 v 81 days), or incidence of short-term intracranial complications (3.8% v 10.5%) or myocardial stun (3.8% v 15.8%).Conclusions: The authors conclude that VV ECMO is as reliable as VA ECMO in newborns with CDH in severe respiratory failure who need ECMO support and who can accommodate the VV double-lumen catheter. Because of its potential advantages, VV ECMO may be the preferred ECMO method in these infants.     

Ex utero intrapartum treatment with extracorporeal membrane oxygenation for severe congenital diaphragmatic hernia

Purpose

The purpose of this study was to determine whether ex utero intrapartum treatment with extracorporeal membrane oxygenation (EXIT to ECMO) is a reasonable approach for managing patients antenatally diagnosed with severe congenital diaphragmatic hernia (CDH).

Methods

A 6-year retrospective review was performed on fetuses with severe CDH (liver herniation and a lung/head ratio <1.4, percentage of predicted lung volume <15, and/or congenital heart disease). Fourteen of the patients underwent EXIT with a trial of ventilation. Fetuses with poor preductal oxygen saturations despite mechanical ventilation received ECMO before their delivery. Maternal-fetal outcomes were analyzed.

Results

There were no maternal-reported complications. Three babies passed the ventilation trial and survived, but 2 of them required ECMO within 48 hours. The remaining 11 fetuses received ECMO before their delivery. Overall survival after EXIT-to-ECMO was 64%. At 1-year follow-up, all survivors had weaned off supplemental oxygen, but 57% required diuretics and/or bronchodilators.

Conclusion

This is the largest reported experience using EXIT to ECMO in the management of severe CDH. The EXIT-to-ECMO procedure is associated with favorable survival rates and acceptable pulmonary morbidity in fetuses expected to have a poor prognosis under conventional management.     

Factors associated with survival in infants with congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation: a report from the Congenital Diaphragmatic Hernia Study Group

Objective

To identify factors associated with survival in patients with congenital diaphragmatic hernia (CDH) treated with extracorporeal membrane oxygenation (ECMO).

Methods

We retrospectively analyzed the data on 3100 patients with CDH in the Congenital Diaphragmatic Hernia Study Group from 82 participating pediatric surgical centers (1995-2004). Covariates considered included prenatal and perinatal clinical information, specifics of surgical repair, and the duration of extracorporeal support.

Result

Nine hundred seven patients from the registry were identified as having been both managed with ECMO and undergone attempted surgical repair. The survival rate for the entire Congenital Diaphragmatic Hernia Study Group registry was 67% and 61% for those receiving ECMO in whom repair was attempted (P < .001). Among ECMO-treated children, survivors had a greater estimated gestational age (38 ± 2 vs 37 ± 2 weeks; P < .01), greater birth weights (3.2 ± 0.5 vs 2.9 ± 0.5 kg; P < .001), were less often prenatally diagnosed (53% vs 63%; P < .01), and were on ECMO for a shorter period of time (9 ± 5 vs 12 ± 5 days; P < .001). In logistic regression models, therapy-related variables, including the duration of ECMO, the nature of diaphragmatic repair, and the type of abdominal closure and certain comorbidities, particularly the presence of a concomitant severe cardiac abnormality, were independently associated with outcome.

Conclusion

Our model identifies a group of pre-surgical and postsurgical parameters that predict survival rate in patients with CDH on ECMO support. This model was derived from the retrospective data from a large database and will need to be prospectively tested.     

Comparison of early versus delayed strategies for repair of congenital diaphragmatic hernia on extracorporeal membrane oxygenation

Purpose

For the last seven years, our institution has repaired infants with CDH that require ECMO early after cannulation. Prior to that, we attempted to decannulate before repair, but repaired on ECMO if we were unable to wean after two weeks. This study compares those strategies.

Challenges to cannulation for extracorporeal support in neonates with right-sided congenital diaphragmatic hernia

Right-sided diaphragmatic defects represent less than 20% of all congenital diaphragmatic hernias (CDH). Recent data suggest that right CDH (R-CDH) may carry a disproportionately high morbidity as well as increased rates of extracorporeal support when compared with left CDH. Treatment of infants with R-CDH may be further complicated by anatomical distortion unique to right-sided defects. We report 2 cases of azygous vein cannulation in neonates with large isolated R-CDH. Both infants had postnatal deteriorations within 48 hours, met our criteria for extracorporeal membrane oxygenation (ECMO), and underwent venoarterial cannulations through the right neck. In each case, the venous cannula passed directly into the azygous vein and failed to provide adequate ECMO support. Echocardiography confirmed both cases of azygous cannulation. In one child, the right atrium was successfully cannulated after 90 minutes of extensive cannula manipulation. This child survived a 5-day ECMO course and is alive at 22-month follow-up. In the second child, despite prolonged efforts at cannula repositioning, cannulation of the right atrium was not achieved. We did not offer central cannulation because of a rapidly deteriorating clinical course, with expiration in several hours. At autopsy, a dilated azygous vein was evident as a result of inferior vena cava compression by a malpositioned liver. The possibility of azygous vein cannulation may be increased in neonates with R-CDH and has not been previously reported. When evaluating infants with R-CDH for ECMO, clinicians must recognize the possibility of azygous cannulation and its potentially lethal consequences, and should anticipate alternative venous cannulation.     

Long-term neurodevelopmental outcomes of congenital diaphragmatic hernia survivors not treated with extracorporeal membrane oxygenation

Background/Purpose

Although there has been a marked improvement in the survival of children with congenital diaphragmatic hernia (CDH) in the past 2 decades, there are few reports of long-term neurodevelopmental outcome in this population. The present study examined neurodevelopmental outcomes in 10- to 16-year-old CDH survivors not treated with extracorporeal membrane oxygenation (ECMO).

Methods

Parents of 27 CDH survivors completed questionnaires assessing medical problems, daily living skills, educational outcomes, behavioral problems, and executive functioning. Fifteen CDH survivors and matched full-term controls completed standardized intelligence, academic achievement, phonological processing, and working memory tests.

Results

Non-ECMO-treated CDH survivors demonstrated high rates of clinically significant difficulties on standardized academic achievement measures, and 14 of the 27 survivors had a formal diagnosis of specific learning disability, attention deficit hyperactivity disorder, or developmental disability. Specific problems with executive function, cognitive and attentional weaknesses, and social difficulties were more common in CDH patients than controls. Perioperative hypocapnia was linked to executive dysfunction, behavioral problems, lowered intelligence, and poor achievement in mathematics.

Conclusions

Non-ECMO-treated CDH survivors are at substantial risk for neurodevelopmental problems in late childhood and adolescence.     

Potential survival benefit with repair of congenital diaphragmatic hernia (CDH) after extracorporeal membrane oxygenation (ECMO) in select patients: Study by ELSO CDH Interest Group

PurposeStudying the timing of repair in CDH is prone to confounding factors, including variability in disease severity and management. We hypothesized that delaying repair until post-ECMO would confer a survival benefit.MethodsNeonates who underwent CDH repair were identified within the ELSO Registry. Patients were then divided into on-ECMO versus post-ECMO repair. Patients were 1:1 matched for severity based on pre-ECMO covariates using the propensity score (PS) for the timing of repair. Outcomes examined included mortality and severe neurologic injury (SNI).ResultsAfter matching, 2,224 infants were included. On-ECMO repair was associated with greater than 3-fold higher odds of mortality (OR 3.41, 95% CI: 2.84–4.09, p < 0.01). The odds of SNI was also higher for on-ECMO repair (OR 1.49, 95% CI: 1.13–1.96, p < 0.01). A sensitivity analysis was performed by including the length of ECMO as an additional matching variable. On-ECMO repair was still associated with higher odds of mortality (OR 2.38, 95% CI: 1.96–2.89, p < 0.01). Results for SNI were similar but were no longer statistically significant (OR 1.33, 95% CI: 0.99–1.79, p = 0.06).ConclusionsOf the infants who can be liberated from ECMO and undergo CDH repair, there is a potential survival benefit for delaying CDH repair until after decannulation.Type of StudyTreatment StudyLevel of EvidenceIII     

Chylothorax after congenital diaphragmatic hernia repair

Purpose

Chylothorax after congenital diaphragmatic hernia (CDH) repair contributes significantly to morbidity. Our aim was to identify factors contributing to chylothorax and effective treatment strategies.

Methods

We reviewed 171 patients with CDH from 1997 to 2008 and analyzed hernia characteristics, extracorporeal membrane oxygenation (ECMO) use, operative details, and treatment approaches for chylothorax.

Results

Ten (7%) patients developed chylothorax; all were left sided. Using univariate analysis, prenatal diagnosis, ECMO use, and patch repair were associated with development of chylothorax. Logistic regression analysis showed that patch repair was the only variable predictive of chylothorax (P = .028; confidence interval, 0.032-0.823). Although survival was not affected, patients with chylothorax had a significant increase in ventilator days and length of stay (t = 3.57; P = .000; t = 2.74; P = .007). All received thoracostomy and total parenteral nutrition. Six patients received octreotide, 5 of whom required pleurectomy because of failed medical management; the remaining patient died of overwhelming sepsis.

Conclusions

The incidence of chylothorax at our institution was relatively low. Patch repair was associated with the formation of chylothorax. Morbidity was substantial, but survival was not significantly affected. Total parenteral nutrition and thoracostomy were appropriate initial treatments. Octreotide was not an effective adjunct. Refractory cases were successfully treated with pleurectomy.     

Antithrombin III administration in neonates with congenital diaphragmatic hernia during the first three days of extracorporeal membrane oxygenation

Purpose

To evaluate the effect of Antithrombin III (ATIII) on blood product requirement in neonates receiving extracorporeal membrane oxygenation (ECMO).

Methods

A retrospective case control study of neonates presenting with or without congenital diaphragmatic hernia (CDH) requiring ECMO between 2006 and 2010 was performed. Patient demographics, laboratory data, and information on blood products administered were compared in patients treated before (n = 37) and after (n = 38) a protocol for antithrombin-III (ATIII) administration was implemented.

Results

During the first three days on ECMO patients with CDH received less fresh frozen plasma (FFP) and platelets after ATIII administration was introduced (78.1 ± 19.2 ml/kg vs. 27.8 ± 6.2 ml/kg, p < 0.007 and 67.8 ± 8.6 ml/kg vs. 47.8 ± 8.4 ml/kg, p = 0.05 respectively), while FFP and platelet administration in patients without CDH was not different between the two periods. Patients both with and without CDH received less packed red blood cell (PRBC) transfusions after the ATIII protocol was introduced (230 ± 51.5 ml/kg vs. 73.8 ± 9.7 ml/kg, p < 0.002 and 173.2 ± 22.2 ml/kg vs. 66.0 ± 6.6 ml/kg, p < 0.001, respectively). Finally, cryoprecipitate administered was not different in patients with and without CDH between the two periods (13 ± 2.9 ml/kg vs. 15.9 ± 7.2 ml/kg, p = NS and 6.1 ± 1.8 ml/kg vs. 3.4 ± 0.6 ml/kg, p = NS, respectively).

Conclusions

Introduction of routine ATIII administration was associated with decreases in FFP, platelet, and PRBC exposure in neonates with CDH and decreases in PRBC transfusions in neonates without CDH during the first three days of ECMO support.     

The split abdominal wall muscle flap repair for large congenital diaphragmatic hernias on extracorporeal membrane oxygenation

Background

Numerous techniques exist for repairing large congenital diaphragmatic hernias (CDHs) including prosthetic patches, tissue-engineered grafts, and various muscle flaps. A split abdominal wall muscle flap is a simple, durable way to repair a large diaphragmatic hernia. This technique has not gained widespread use, and some have suggested that it would be inappropriate in the setting of extracorporeal membrane oxygenation (ECMO) because of bleeding risk. We present our series of diaphragmatic hernias with a focus on those repaired with the split abdominal wall technique while on ECMO.

Methods

A retrospective, single-institution chart review was performed on all patients who underwent surgical repair for CDH over 6 years beginning in August 2000.

Results

Seventy-five patients underwent repair. Sixteen were performed with patients on ECMO. Of these, 4 were closed primarily, 7 used a prosthetic patch, and 5 used a split abdominal wall muscle flap. Two patients in the prosthetic group developed a recurrent hernia, and 2 required reoperation for bleeding while on ECMO. No reoperations for bleeding were required in the abdominal muscle flap group.

Conclusions

The split abdominal wall muscle flap can be safely performed on anticoagulated patients. We believe it is a practical option for repairing large CDHs.     

Identifying neonates at a very high risk for mortality among children with congenital diaphragmatic hernia managed with extracorporeal membrane oxygenation

Purpose

The purpose of this study was to identify mortality risk factors in children with congenital diaphragmatic hernia (CDH) treated with extracorporeal membrane oxygenation (ECMO) and generate a prediction score for those at a very high risk for mortality.

Methods

Data on first ECMO runs of all neonates with CDH, between January 1997 and June 2007, were obtained from the Extracorporeal Life Support Organization registry (N = 2678). The data were split into “training data (TD)” (n = 2006) and “validation data” (n = 672). The primary outcome analyzed was in-hospital mortality. Modified Poisson regression was used for analyses.

Results

Overall in-hospital mortality among 2678 neonates (males, 57%; median age at ECMO, 1 day) was 52%. The univariate and multivariable analyses were performed using TD. An empirically weighted mortality prediction score was generated with possible scores ranging from 0 to 35 points. Of 69 who scored 14 or higher in the TD, 62 died (positive predictive value [PPV], 90%), of 37 with 15 or higher, 35 died (PPV, 95%), of 23 with 16 or higher, 22 died (PPV, 96%). A cut-off point of 15 was chosen and was tested using the separate validation dataset. In validation data, the cut-off point 15 had a PPV of 96% (23 died of 24).

Conclusion

Scoring 15 or higher on the prediction score identifies neonates with CDH at a very high risk for mortality among those managed with ECMO and could be used in surgical decision making and counseling.     

Congenital diaphragmatic hernia repair in patients on extracorporeal membrane oxygenation: How early can we repair?

Background

The benefits to early repair (< 72?h postcannulation) of infants with congenital diaphragmatic hernia (CDH) on extracorporeal membrane oxygenation (ECMO) are increasingly recognized. Yet it is not known if even earlier repair (< 24?h) results in comparable or improved patient outcomes. The goal of this study was to compare “super-early” (< 24?h) to early repair (24-72?h) of CDH patients on ECMO.

Protocolized management of infants with congenital diaphragmatic hernia: effect on survival

Background/Purpose

In 2006, we introduced a new protocol for congenital diaphragmatic hernia (CDH) management featuring nitric oxide in the delivery room, gentle ventilation, lower criteria for extracorporeal membrane oxygenation (ECMO), and appropriately timed operative repair on ECMO. Our goals were to assess outcomes after institution of this protocol and to compare results with historical controls.

Methods

Charts were reviewed of all newborns admitted to a large metropolitan children's hospital from 2002 to 2009 with a diagnosis of CDH. Data were recorded regarding delivery, ECMO, operative repair, length of stay, comorbidities/anomalies, complications, and survival. Postprotocol outcomes were compared to those from the preprotocol era and to data from the international CDH Registry.

Results

Comparison of the protocolized group (n = 43) to the historical group (n = 51) revealed no significant differences in gestational age, birth weight, Apgar scores, or comorbidities. New treatment strategies substantially improved survival to discharge (67% preprotocol, 88% postprotocol; P = .015). Among ECMO patients, survival increased to 82% (20% preprotocol; P = .002).

Conclusions

Our new protocol significantly improved survival to discharge for newborns with CDH. Institution of such a protocol is valuable in improving outcomes for patients with CDH and merits consideration for widespread adoption.     

Influence of extracorporeal membrane oxygenation on subsequent surgeries after congenital diaphragmatic hernia repair

Purpose

Congenital diaphragmatic hernia (CDH) is a complex anomaly requiring intensive pulmonary and hemodynamic management. Survival has increased in this population placing them at risk for subsequent morbidities including surgery. The purpose of this study is to review the need for subsequent surgeries in the CDH population.

Methods

After receiving institutional review board approval, a retrospective chart review of all CDH patients between 1980 and 2007 was conducted noting subsequent surgeries and the impact of extracorporeal membrane oxygenation (ECMO) on the types of surgical procedures. Comparison of groups was done by Fisher's Exact test or nonparametric Wilcoxon rank-sum test where appropriate. A P value of less than .05 was considered significant.

Results

Data were analyzed for 227 of 294 patients during this period. Extracorporeal membrane oxygenation support was used in 45% of patients. Subsequent surgery was required in 117 patients. Seventy patients in the ECMO group (69%) required a subsequent operation. The most common operative procedures included inguinal hernia/orchiopexy, antireflux, and recurrent diaphragmatic hernias.

Conclusion

In this series, ECMO survivors are at a high risk for requiring subsequent surgeries compared to the total CDH group. This information can be used as an education tool for referring physicians and parents as they care for this group of children.     

Extracorporeal membrane oxygenation and congenital diaphragmatic hernia: modification of the pulmonary vasoactive profile

We studied the vasoactive profile of a term infant with congenital diaphragmatic hernia and intractable pulmonary hypertension who was refractory to conventional medical management despite an early stable period. Plasma prostanoid vasoconstrictor thromboxane A2 (TxB2) levels were elevated prior to ECMO at 150pg/mL, rose to 310pg/mL with the first hour of bypass and remained elevated until 72 hours by which time they fell to less than 50pg/mL. This coincided with the decreased extracorporeal circulatory support needed to maintain systemic arterial pO2 between 70 to 90 torr. Pulmonary vasodilator prostacyclin (6-keto-PGF1 alpha) was minimally elevated prior to bypass a 50pg/mL and became undetectable. Catecholamine levels were markedly elevated prior to ECMO at 4,000pg/mL with no demonstrable pulmonary extraction of norepinephrine. Though catecholamine levels remained nonspecifically elevated, pulmonary metabolism of norepinephrine improved with bypass time to 48% at 96 hours and coincided with the overall improvement of the infant's respiratory function. These data suggest pulmonary hypertension associated with congenital diaphragmatic hernia is at least partially precipitated by alterations in prostanoid homeostasis as selective activation of thromboxane synthetase pathways rather than nonspecific activation of the entire archidonate cascade. While ECMO per se may have no lasting effect on prostanoid homeostasis, ECMO can allow a period of cardiopulmonary rest during which more physiologic prostanoid levels are established. Although activation of the sympatho-adrenal axis may contribute to pulmonary hypertension, the role of catecholamines in this infant is not clear. Return of the lungs ability to clear norepinephrine may be an additional marker of biologic lung recovery.     

Costs of congenital diaphragmatic hernia repair in the United States-extracorporeal membrane oxygenation foots the bill

Background

Congenital diaphragmatic hernia (CDH) is the costliest noncardiac congenital defect. Extracorporeal membrane oxygenation (ECMO) is a treatment strategy offered to those babies with CDH who would not otherwise survive on conventional therapy. The primary objective of our study was to identify the leading source of expenditures in CDH care.

Methods

All patients surviving CDH repair were identified in the Kids' Inpatient Database (KID) from 1997 to 2006, with costs converted to 2006 US dollars. Patients were categorized into groups based on severity of disease for comparison including CDH repair only, prolonged ventilator dependence, and ECMO use. Factors associated with greater expenditures in CDH management were analyzed using a regression model.

Results

Eight hundred thirty-nine patients from 213 hospitals were studied. Extracorporeal membrane oxygenation use decreased from 18.2% in 1997 to 11.4% in 2006 (P = .002). Congenital diaphragmatic hernia survivors managed with ECMO cost more than 2.4 times as much as CDH survivors requiring only prolonged ventilation postrepair and 3.5 times as much as those with CDH repair only (both P < .001). Age, multiplicity of diagnoses, patient transfer, inhaled nitric oxide use, prolonged ventilation, and ECMO use were all associated with higher costs. Extracorporeal membrane oxygenation use was the single most important factor associated with higher costs, increasing expenditures 2.4-fold (95% confidence interval, 2.1-2.8). Though the CDH repair with ECMO group constituted 12.2% of patients, this group has the highest median costs ($156,499.90/patient) and constitutes 28.5% of national costs based on CDH survivors in the KID. Annual national cost for CDH survivors is $158 million based on the KID, and projected burden for all CDH patients exceeds $250 million/year.

Conclusions

Extracorporeal membrane oxygenation use is the largest contributing factor to the economic burden in CDH. With limited health care resources, judicious resource utilization in CDH care merits further study.     

Redefining outcomes in right congenital diaphragmatic hernia

Purpose

Available data comparing the management and outcome of right-sided (R-CDH) vs left-sided congenital diaphragmatic hernia (L-CDH) are inconsistent. Large-volume CDH studies are limited by small numbers of R-CDH or are confounded by compilations from multiple institutions with multiple treatment strategies. Consequently, they are underpowered to draw conclusions. To define the behavior and outcomes of R-CDH better, we report the largest single-institution series of R-CDH and ask if factors traditionally linked to poor prognosis in L-CDH were applicable to R-CDH.

Methods

We reviewed a single institution's experience with 267 consecutive evaluable neonates with unilateral CDH repaired from 1990 to 2006, with specific focus on R-CDH. χ² tests were performed for disease-related categorical variables. Two-tailed unpaired t tests were used for continuous variables. Factors associated with morbidity and survival were determined by univariate regression. Statistical significance was set at P < .05.

Results

Forty right-sided (15%) and 227 (85%) left-sided cases of CDH were identified. Prenatal diagnosis was made in 20 right-sided vs 170 left-sided defects (50% vs 75%, P < .01). Survival was 22 of 40 in R-CDH compared with 175 of 227 in L-CDH (55% vs 77%, P < .01). Extracorporeal membrane oxygenation was required in 16 right-sided and 33 left-sided cases (40% vs 15%, P < .001). A diaphragmatic patch was used in 22 of 29 right-sided compared with 82 of 199 left-sided repairs (76% vs 41%, P < .01); rates of abdominal wall prosthesis were also higher in right-sided hernias (38% vs 19%, P < .05). No differences were detected in right-sided vs left-sided recurrences (14% vs 8%, P = .38), mean time from birth to operation (5.3 vs 4.8 days, P = .80), or presence of cardiac anomalies (15% vs 12%, P = .63). Morbidity persisting beyond 6 months of age was present in 16 of 22 R-CDH survivors compared with 76 of 175 L-CDH survivors (73% vs 43%, P > .05). Among R-CDHs, prenatal diagnosis was the only factor to predict survival by univariate regression (P < .01). Use of a prosthesis in the diaphragm (P < .05) for R-CDH repair correlated with morbidity.

Conclusion

Although previous reports suggest that associated anomalies, need for extracorporeal membrane oxygenation, and time to repair can influence L-CDH survival, these data do not support extrapolation to R-CDH survival. Right-sided CDH carries a disproportionately high morbidity and mortality. Prenatal diagnosis was the only factor predictive of R-CDH survival. Morbidity may correlate with use of prosthetic material for R-CDH repair. Right-sided CDH is a unique disease that may require a modified antenatal consultation.     

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.