Evolution of the technique of congenital diaphragmatic hernia repair on ECMO

Update on Management and Outcomes of Congenital Diaphragmatic Hernia

Infants with congenital diaphragmatic hernia (CDH) benefit from comprehensive multidisciplinary teams that have experience in caring for the unique and complex issues associated with CDH. Despite prenatal referral to specialized high-volume centers, advanced ventilation strategies and pulmonary hypertension management, and extracorporeal membrane oxygenation, mortality and morbidity remain high. These infants have unique and complex issues that begin in fetal and infant life, but persist through adulthood. Here we will review the literature and share our clinical care pathway for neonatal care and follow up. While many advances have occurred in the past few decades, our work is just beginning to continue to improve the mortality, but also importantly the morbidity of CDH.

Surgical approaches to congenital diaphragmatic hernia

Surgical repair of the diaphragm is essential for survival in congenital diaphragmatic hernia (CDH). There are many considerations surrounding the operation - why the operation matters, optimal timing of repair and its relation to extracorporeal life support (ECLS) use, minimally invasive versus open approaches, and strategies for reconstruction. Surgery is both affected by, and affects, the physiology of these infants and is an important factor in determining long-term outcomes. Here we discuss the evidence and provide insight surrounding this complex decision making, technical pearls, and outcomes in repair of CDH.

Antifibrinolytic and Adjunct Hemostatic Agents: The Pediatric Extracorporeal Membrane Oxygenation Anticoagulation CollaborativE Consensus Conference

OBJECTIVES

To derive systematic-review informed, modified Delphi consensus regarding antifibrinolytic and adjunct hemostatic agents in neonates and children supported with extracorporeal membrane oxygenation (ECMO) for the Pediatric ECMO Anticoagulation CollaborativE consensus conference.

DATA SOURCES

A structured literature search was performed using PubMed, EMBASE, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021.

STUDY SELECTION

Use of antifibrinolytics (epsilon-aminocaproic acid [EACA] or tranexamic acid), recombinant factor VII activated (rFVIIa), or topical hemostatic agents (THAs).

DATA EXTRACTION

Two authors reviewed all citations independently, with a third independent reviewer resolving conflicts. Eleven references were used for data extraction and informed recommendations. Evidence tables were constructed using a standardized data extraction form.

MEASUREMENTS AND MAIN RESULTS

Risk of bias was assessed using the Quality in Prognosis Studies tool. The evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation system. Forty-eight experts met over 2 years to develop evidence-based recommendations and, when evidence was lacking, expert-based consensus statements for the management of bleeding and thrombotic complications in pediatric ECMO patients. A web-based modified Delphi process was used to build consensus via the Research And Development/University of California Appropriateness Method. Consensus was defined as greater than 80% agreement. One weak recommendation and three consensus statements are presented.

CONCLUSIONS

Evidence supporting recommendations for administration of antifibrinolytics (EACA or tranexamic acid), rFVIIa, and THAs were sparse and inconclusive. Much work remains to determine effective and safe usage strategies.

The Timing of Congenital Diaphragmatic Hernia Repair on Extracorporeal Membrane Oxygenation Impacts Surgical Bleeding Risk

BACKGROUND

The optimal timing of surgical repair for infants with congenital diaphragmatic hernia (CDH) treated with extracorporeal membrane oxygenation (ECMO) support remains controversial. The risk of surgical bleeding is considered by many centers as a primary factor in determining the preferred timing of CDH repair for infants requiring ECMO support. This study compares surgical bleeding following CDH repair on ECMO in early versus delayed fashion.

METHODS

A retrospective review of 146 infants who underwent CDH repair while on ECMO support from 1995 to 2021. Early repair occurred during the first 48 h after ECMO cannulation (ER) and delayed repair after 48 h (DR). Surgical bleeding was defined by the requirement of reoperative intervention for hemostasis or decompression.

RESULTS

102 infants had ER and 44 infants DR. Surgical bleeding was more frequent in the DR group (36% vs 5%, p < 0.001) with an odds ratio of 11.7 (95% CI: 3.48-39.3, p < 0.001). Blood urea nitrogen level on the day of repair was significantly elevated among those who bled (median 63 mg/dL, IQR 20-85) vs. those who did not (median 9 mg/dL, IQR 7-13) (p < 0.0001). Duration of ECMO support was shorter in the ER group (median 13 vs 18 days, p = 0.005). Survival was not statistically different between the two groups (ER 60% vs. DR 57%, p = 0.737).

CONCLUSION

We demonstrate a significantly lower incidence of bleeding and shorter duration of ECMO with early CDH repair. Azotemia was a strong risk factor for surgical bleeding associated with delayed CDH repair on ECMO.

LEVEL OF EVIDENCE

Level III cohort study.

Congenital Heart Disease with Congenital Diaphragmatic Hernia: Surgical Decision Making and Outcomes

OBJECTIVE

To describe the types of congenital heart disease (CHD) in a congenital diaphragmatic hernia (CDH) cohort in a large volume center and evaluate surgical decision making and outcomes based on complexity of CHD and associated conditions.

STUDY DESIGN

A retrospective review of patients with CHD and CDH diagnosed by echocardiogram between 01/01/2005 and 07/31/2021. The cohort was divided into 2 groups based on survival at discharge.

RESULTS

Clinically important CHD was diagnosed in 19% (62/326) of CDH patients. There was 90% (18/20) survival in children undergoing surgery for both CHD and CDH as neonates, and 87.5 (22/24) in those undergoing repair initially for CDH alone. A genetic anomaly identified on clinical testing was noted in 16% with no significant association with survival. A higher frequency of other organ system anomalies was noted in nonsurvivors compared with survivors. Nonsurvivors were more likely to have unrepaired CDH (69% vs 0%, P < .001) and unrepaired CHD (88% vs 54%, P < .05), reflecting a decision not to offer surgery.

CONCLUSIONS

Survival was excellent in patients who underwent repair of both CHD and CDH. Patients with univentricular physiology have poor survival and this finding should be incorporated into pre and postnatal counseling about eligibility for surgery. In contrast, patients with other complex lesions including transposition of the great arteries have excellent outcomes and survival at 5 years follow-up at a large pediatric and cardiothoracic surgical center.

Antithrombin III infusion improves anticoagulation in congenital diaphragmatic hernia patients on extracorporeal membrane oxygenation

PURPOSE

Achieving effective anticoagulation during neonatal extracorporeal membrane oxygenation (ECMO) without increasing the risk of hemorrhage remains challenging. The use of antithrombin III (AT-III) for this purpose has been examined, but studies have been limited to intermittent bolus dosing. We aimed to evaluate the efficacy and safety of an institutionally developed AT-III continuous infusion protocol in neonates receiving ECMO for the treatment of congenital diaphragmatic hernia (CDH).

METHODS

In this single center, retrospective study, all neonates with a CDH who received ECMO support during the study period were included. Data on anticoagulation labs and therapy, life-threatening bleeding, and circuit changes were analyzed.

RESULTS

Eleven patients were divided into two groups: patients with AT-III continuous infusion (n = 5) and without (n = 6). There were no differences in the gestational age (p = 0.29), sex (p = 1.00), ECMO duration (p = 0.59), or initial AT-III levels (p = 0.76) between groups. Patients in the AT-III infusion group had on average 18.5% higher AT-III levels (p < 0.0001). Patients receiving continuous AT-III infusions spent a significantly higher percentage of ECMO time within the therapeutic range, measured using anti-Factor Xa levels (64.9±4.2% vs. 29.1±8.57%, p = 0.008), and required fewer changes to the heparin infusion rate (6.48±0.88 vs 2.38±0.36 changes/day changes/day, p = 0.005). Multivariate analysis revealed continuous infusion of AT-III did not increase the rate of intracranial or surgical bleeding (p = 0.27).

CONCLUSION

AT-III as a continuous infusion in CDH neonates on ECMO provides a decreased need to modify heparin infusion and more consistent therapeutic anticoagulation without increasing the risk of life-threatening bleeding.

Surgery in Neonatal and Pediatric ECMO Patients Other Than Congenital Diaphragmatic Hernia Repair: A 10-Year Experience

Aim of Study: The use of extracorporeal membrane oxygenation (ECMO) has increased as a result of technological developments and the expansion of indications. Relatedly, the number of patients undergoing surgery during ECMO is also rising, at least in the adult population. Little is known on surgery in children during ECMO-therapy. We therefore aimed to assess the frequencies and types of surgical interventions in neonatal and pediatric patients on ECMO and to analyze surgery-related morbidity and mortality. Methods: We retrospectively collected information of all patients on ECMO over a 10-year period in a single tertiary and designated ECMO-center, excluding patients undergoing cardiac surgery, and correction of congenital diaphragmatic hernia. Chi-squared test and Mann-Whitney U test were used to analyze data. Main Results: Thirty-two of 221 patients (14%) required surgery when on ECMO. Common interventions were thoracotomy (32%), laparotomy (23%), fasciotomy (17%), and surgical revision of ECMO (15%). Complications occurred in 28 cases (88%), resulting in a 50% in-hospital mortality rate. Surgical patients had a longer ICU stay and longer total hospital stay compared to those not receiving surgery during ECMO. No significant difference in mortality was found when comparing surgical to non-surgical patients (50 vs. 41%). Conclusions: Approximately one in seven neonatal or pediatric patients required surgical intervention during ECMO, of whom almost 90% developed a complication, resulting in a 50% mortality rate. These results should be taken into account in counseling.

The role of ECMO in the management of congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is the most common indication for extra-corporeal membrane oxygenation (ECMO) for neonatal respiratory failure. CDH management is evolving with advanced prenatal diagnostic imaging modalities. The risk profiles of infants receiving ECMO for CDH are shifting towards higher risk. Many clinicians are developing and following clinical practice guidelines to standardize and optimize the care of CDH neonates. Despite these efforts, there are significant differences in the practice patterns among ECMO centers as to how and when they choose to initiate ECMO for CDH, when they believe repair is safe, as well as many other nuances that are based on center experience or style. The purpose of this report is to summarize our current understanding of the new and recent developments regarding management of infants with CDH managed with ECMO.

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.

METHODS

A retrospective review of infants with CDH placed on ECMO (2004-2017; n = 72) was performed. Data collected on the patients repaired while on ECMO within 72 h of cannulation (n = 33) included pre- and postnatal disease severity stratification variables and postnatal outcomes. Comparison groups were those patients repaired within 24 h of cannulation (n = 14) and those repaired between 24 and 72 h postcannulation (n = 19).

RESULTS

Patients undergoing "super-early" (<24 h) repair had an average survival of 71.4% compared to the average survival of 59.7% in the early repair group. Pre- and postnatal variables predicting disease severity were not significantly different between the groups. Mean hospital stays, ventilator days, and cannulation days were statistically similar between the groups.

CONCLUSIONS

Repair of patients with CDH patients on ECMO at less than 24 h postcannulation achieves outcomes that are comparable to those of repair between 24 and 72 h. While the present data suggest that there is not a "too early" time point for CDH repair on ECMO, larger multicenter studies are needed to validate our findings and determine the overall benefits.

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

Level III.

Evaluating the utility of the "late ECMO repair": a congenital diaphragmatic hernia study group investigation

PURPOSE

Optimal timing of congenital diaphragmatic hernia (CDH) repair in patients requiring extracorporeal membrane oxygenation (ECMO) remains controversial. The "late ECMO repair" is an approach where the patient, once deemed stable for decannulation, is repaired while still on ECMO to enable expeditious return to ECMO if surgery induces instability. The goal of this study was to investigate the potential benefit of this approach by evaluating the rate of return to ECMO after repair.

METHODS

The CDH Study Group database was used to analyze CDH patients requiring ECMO support. The primary outcome was return to ECMO within 72 h of CDH repair among those repaired following ECMO decannulation ("post-ECMO" patients). Secondary outcomes were death within 72 h of repair and cumulative death and return to ECMO rate.

RESULTS

A total of 668 patients were repaired post-ECMO decannulation. Six patients (0.9%) in the post-ECMO group required return to ECMO within 72 h of surgery and a total of 19 (2.8%) died or returned to ECMO within 72 h of surgery.

CONCLUSION

The rate of return to ECMO and death following CDH repair is extremely low and does not justify the risks inherent to "on-ECMO" repair. Patients stable to come off ECMO should undergo repair after decannulation.

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.

METHODS

From 2002 to 2016, 65 infants with CDH required ECMO. 67.7% were repaired on ECMO, and 27.7% were repaired after decannulation. Data were compared between patients repaired ≤5days after cannulation ("early protocol", n=30) and >5days after cannulation or after de-cannulation ("late protocol", n=35). We used Cox regression to assess differences in outcomes between groups.

RESULTS

Survival for the early and late protocol groups was 43.3% and 68.8%, respectively (p=0.0485). For patients that were successfully decannulated before repair, survival was 94.4%. Moreover, the early repair protocol was associated with prolongation of ECMO (16.8±7.4 vs. 12.6±6.8days, p=0.0216). After multivariate regression, the early repair protocol was an independent predictor of both mortality (HR=3.48, 95% CI=1.28-9.45, p=0.015) and days on ECMO (IRR=1.39, 95% CI=1.07-1.79, p=0.012). All bleeding occurred in patients repaired on ECMO (29.5%, 13/44).

CONCLUSIONS

Our data suggest that protocolized CDH repair early after ECMO cannulation may be associated with increased mortality and prolongation of ECMO. However, early repair is not necessarily harmful for those patients who would otherwise be unable to wean from ECMO before repair. Further work is needed to better move towards individualized patient care.

TYPE OF STUDY

Treatment Study.

LEVEL OF EVIDENCE

Level III.

Optimal timing of congenital diaphragmatic hernia repair in infants on extracorporeal membrane oxygenation

Extracorporeal membrane oxygenation (ECMO) is a vital pre-operative adjunct for the stabilization of patients with severe congenital diaphragmatic hernia (CDH) that develop cardiorespiratory failure. The optimal timing of diaphragmatic repair in patients with CDH that require ECMO remains controversial. This article offers a review of the data available addressing the risks and outcomes of patients who require ECMO support with regard to timing of repair.

Controversies in the management of severe congenital diaphragmatic hernia

Despite years of progress in perinatal care, severe congenital diaphragmatic hernia (CDH) remains a clinical challenge. Controversies include almost every facet of clinical care: the definition of severe CDH by prenatal and postnatal criteria, fetal surgical intervention, ventilator management, pulmonary hypertension management, use of extracorporeal membrane oxygenation, surgical considerations, and long-term follow-up. Breakthroughs are likely only possible by sharing of experience, collaboration between institutions and innovative therapies within well-designed multicenter clinical trials.

Pulmonary development considerations in the surgical management of congenital diaphragmatic hernia

Congenital diaphragmatic hernia remains a clinical challenge for both neonatologists and pediatric surgeons. Advancements in mechanical ventilation strategies and neonatal intensive care have improved survival and transformed treatment of congenital diaphragmatic hernia from emergent surgery to early stabilization of the newborn followed by delayed repair of the diaphragmatic defect. Surgical technique has evolved and minimally invasive surgical approaches to close the diaphragmatic defect in these babies will likely improve with increasing experience. Finally, as more patients are diagnosed prenatally, attempts have been made to close the diaphragmatic defect prenatally. Unfortunately, this approach did not change the outcome of affected babies. Recently, progress has been made with prenatal tracheal plugging to improve prenatal lung development. In the near future experimental studies will start to explore new ways of treating affected babies prior to birth. This article reviews the evolution of the current treatment strategies in congenital diaphragmatic hernia and its future directions.

Outcomes after muscle flap vs prosthetic patch repair for large congenital diaphragmatic hernias

BACKGROUND

Repair of large congenital diaphragmatic hernia (CDH) defects still pose a significant challenge, as the defects cannot be repaired primarily. Two techniques have been widely used: autologous anterior abdominal wall muscle flap and prosthetic patch. The latter has been used more often. Our goal was to compare the short-term and long-term outcomes of these 2 approaches.

METHODS

This is a retrospective review of all neonates undergoing CDH repair at our institution from 1969 to 2006.

RESULTS

Of 188 children undergoing surgery for CDH, primary repair could not be accomplished in 51 infants (27%). Nineteen had muscle flap repair, and 32 had prosthetic patch repair (Gore-Tex [W.L. Gore and Associates, Flagstaff, AZ], n = 15; Marlex [Bard Inc, Cranston, NJ], n = 9; Surgisis [Cook, Bloomington, IN], n = 5; SILASTIC [Dow Corning, Midland, MI], n = 3). There was no significant difference in gestational age or birth weight between groups. Three patients developed an abdominal wall defect at the muscle flap donor site, but none required surgical intervention. Chest wall deformities were found in 9 patients, 3 after a muscle flap and 6 after a prosthetic patch (P = .7). Postoperative bowel obstruction occurred in 3 muscle flap patients and 1 patch patient (P = .2). There were 10 recurrences among survivors: 2 after a muscle flap and 8 after a prosthetic patch (P = .3) There were 2 deaths among the muscle flap patients (10%), and 3 deaths among the prosthetic patch repair patients (9%) (P = .1). Results were confirmed after controlling for age and comorbidities between both groups in a multivariate logistic regression.

CONCLUSION

These results suggest that autologous anterior abdominal wall muscle flap and prosthetic patch repairs provide similar short-term and long-term outcomes.

Congenital diaphragmatic hernia requiring extracorporeal membrane oxygenation: does timing of repair matter?

PURPOSE

Severe congenital diaphragmatic hernia (CDH) requiring extracorporeal membrane oxygenation (ECMO) is associated with high mortality. Timing of CDH repair relative to ECMO therapy remains controversial. Our hypothesis was that survival would significantly differ between those who underwent repair during ECMO and those who underwent repair after ECMO therapy.

METHODS

We examined deidentified data from the CDH study group (CDHSG) registry from 1995 to 2005 on patients who underwent repair and ECMO therapy (n = 636). We used Cox regression analysis to assess differences in survival between those who underwent repair during and after ECMO.

RESULTS

Five covariates were significantly associated with mortality as follows: timing of repair relative to ECMO (P = .03), defect side (P = .01), ECMO run length (P < .01), need for patch repair (P = .03), birth weight (P < .01), and Apgar score at 5 minutes (P = .03). Birth year, inborn vs transfer status, diaphragmatic agenesis, age at repair, and presence of cardiac or chromosomal abnormalities were not associated with survival. Repair after ECMO therapy was associated with increased survival relative to repair on ECMO (hazard ratio, 1.407; P = .03).

CONCLUSION

These data suggest that CDH repair after ECMO therapy is associated with improved survival compared to repair on ECMO, despite controlling for factors associated with the severity of CDH.

Postnatal management and long-term outcome for survivors with congenital diaphragmatic hernia

Significant advances in the postnatal management of patients with congenital diaphragmatic hernia (CDH) have resulted in a remarkable improvement in survival rates over the past two decades. The success of current postnatal management of CDH patients has rendered fetal intervention to be limited to the most severe cases, and the role for prenatal treatment of CDH patients remains unclear. The adoption of lung-preserving strategies including high-frequency oscillatory ventilation (HFOV) and extracorporeal membrane oxygenation (ECMO) have improved CDH outcomes especially in those patients with significant ventilatory or circulatory compromise. Survival rates of up to 90% are being reported in some high-volume centers. However, the increased survival in CDH patients has been accompanied by an increase in neurological, nutritional and musculoskeletal morbidity among the long-term survivors. This has resulted in the need to provide resources for the long-term follow-up and support of this patient population. In this article, the postnatal management strategies and primary and secondary outcomes of high-volume international pediatric surgical centers will be reviewed. Finally, the role of a multidisciplinary management team for the follow-up of long-term CDH survivors will be discussed.

Abdominal Compartment Syndrome Complicating Paediatric Extracorporeal Life Support: Diagnostic and Therapeutic Challenges

We report three paediatric cases, and summarise the reported experience in two others, with cardiorespiratory failure requiring extracorporeal life support for which supportive pump flows could not be maintained due to abdominal compartment syndrome.

In two of our patients, the mechanism of abdominal compartment syndrome was massive intra-abdominal fluid extravasation secondary to sepsis, while in the third, the mechanism was post-traumatic intra-abdominal haemorrhage. Although all three children eventually died, decompressive laparotomy and arrest of haemorrhage in the trauma patient restored venous return and enabled technically adequate extracorporeal life support. In two previously reported cases of sepsis with massive fluid resuscitation resulting in abdominal compartment syndrome, one patient died without attempted decompression, while the other patient survived after peritoneal catheter placement restored venous return.

Once correctable causes of inadequate venous cannula drainage have been excluded, abdominal compartment syndrome should be considered in any patient on extracorporeal life support with a taut abdomen and reduced venous return. If abdominal compartment syndrome can be proven or is strongly suspected, there may be a role for selective decompressive laparotomy.

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.

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.

Diaphragmatic hernia: diagnostic approaches with review of the literature

Because surgical repair is indicated for the treatment of diaphragmatic hernia (DH), preoperative imaging of the diaphragmatic defect, hernia content, and associated complications with other organ's pathologies is important. While various techniques can be used on imaging of DHs, selection of the most effective but the least invasive technique will present the most accurate findings about DH, and will facilitate the management of DH. We reviewed the diaphragmatic hernia types associated with our cases, and we discussed the preferred imaging modalities for different DHs with review of the literature. We evaluated the imaging findings of 21 DH cases. They were Morgagni's hernia (n=4), Bochdalek hernia (n=2), iatrogenic DH (n=4), traumatic DH (n=6), and hiatal hernia (n=5). Although its limited findings on DH and indirect findings about the diaphragmatic rupture, plain radiography is firstly preferred technique on DH. We found that ultrasound (US) is a useful tool on DH, on traumatic DH cases especially. Not only it shows diaphragmatic continuity and herniated organs, but also it reveals associated abdominal organ's pathologies. Computed tomography (CT) scan is most effective in many DH cases. It shows the herniated abdominal organs together with complications, such as intestinal strangulation, haemothorax, and rib fractures. We stressed that Multislice CT scan with coronal and sagittal reformatted images is the most effective and useful imaging technique on DH. With high sensitivity for soft tissue, MR imaging may be performed in the selected patients, on the late presenting DH cases or on the cases of the diagnosis still in doubt especially.

The role of extracorporeal membrane oxygenation in congenital diaphragmatic hernia

The aim of this paper is to review the role of extracorporeal membrane oxygenation (ECMO) in neonates with severe acute hypoxemic respiratory failure secondary to congenital diaphragmatic hernia (CDH). The difficulties in identifying patients with fatal lung hypoplasia are highlighted and the role of adjunctive therapies on ECMO (surfactant, inhaled nitric oxide, high-frequency ventilation and liquid lung distension) as well as the timing of surgical repair is discussed. Survivors of severe CDH who have been supported on ECMO have significant late mortality and morbidity. There remains a need for a randomized controlled trial of the role of ECMO in neonates with severe CDH.

Toldt's fascia flap: a new technique for repairing large diaphragmatic hernias

The most popular techniques for repairing large diaphragmatic defects involve the use of synthetic patches. We present an alternative approach using living tissue. We reviewed our cases of congenital diaphragmatic hernia (CDH) diagnosed within the first 24 h of life from 1991 to 2003. Toldt's fascia (TF) flap was used to repair defects that were too large to repair primarily even though the anterior rim of the diaphragm was present. After confirming that a small medial muscle remnant of the diaphragm was present, its mesothelial covering was incised, and the incision was extended to the TF far enough to create a flap sufficiently large to repair the defect. The TF flap, consisting of the small medial muscle remnant, TF, peritoneum, and retroperitoneal connective tissue, was mobilized carefully from the ipsilateral kidney and adrenal gland, and the repair completed with interrupted sutures using nonabsorbable material. We used this TF flap approach in seven of 43 patients with CDH. Two had right-sided CDH. Six survived. The mean size of the diaphragmatic defects in the seven TF flap cases was 5.43+/-0.53 x 3.86+/-1.07 cm, which was significantly larger than the defects in direct primary repair cases (3.40+/-0.77 x 2.03+/-0.59 cm) (p<0.01). The six survivors had good outcomes, and none of them have had recurrence of herniation or required any additional surgical intervention (mean follow-up period: 4.7 years). To the best of our knowledge, this is the first report of TF being used to repair large diaphragmatic hernias. Our technique is simple and has proven to be reliable for durable restoration of the diaphragm, suggesting that it could reduce the dependence on synthetic patch repair, which is associated with certain long-term complications.

Major abdominal surgery of the neonate: anaesthetic considerations

The anaesthetic handling of neonates scheduled for major abdominal surgical procedures is one of the most demanding tasks that can confront an anaesthesiologist. This chapter will review the specific physiological characteristics of the newborn with relevance to anaesthesia and will also provide robust guidelines for the anaesthetic handling of the most frequent diagnoses that need major abdominal surgery during the neonatal period.

Congenital Diaphragmatic Hernia Repair on Extracorporeal Life Support: A Decade of Lessons Learned

Congenital diaphragmatic hernia (CDH) is a vexing anomaly that manifests with variable pulmonary compromise in neonates. More than one-third of neonates with CDH require extracorporeal membrane oxygenation (ECMO) for refractory pulmonary hypertension (PHN). To assess the outcome of neonates having CDH repair on ECMO, we reviewed our experience for babies treated between 1992 and 2003. Of 97 neonates with CDH, 40 required ECMO, and 30 were repaired on bypass. Eighteen were supported by veno-venous bypass (VV) and 12 by veno-arterial bypass (VA). While on ECMO, transfusion requirements increased twofold postoperatively (15 to 33 cc · kg-1 · day-1, P = 0.03) and then significantly decreased after decannulation (1.5 cc · kg-1 · day-1, P < 0.01). Non-intracranial hemorrhage occurred in 7 (23%) infants and intracranial hemorrhage in 3 (10%). Twelve (40%) infants died; one (3%) on ECMO secondary to refractory PHN. The mean length of stay for the 18 (60%) survivors was 48 days. Comparisons between survivors and nonsurvivors showed a significantly increased mortality for infants placed on VA bypass ( P < 0.01). However, no other variable was predictive of survival. We conclude that CDH repair on ECMO is technically feasible, shows similar survival to the Extracorporeal Life Support Organization (ELSO) registry, and is associated with few bleeding complications.

The split abdominal wall muscle flap--a simple, mesh-free approach to repair large diaphragmatic hernia

PURPOSE

The authors present a technique to repair large diaphragmatic hernias that is simple, can be done primarily, and offers a durable closure with living tissue.

METHODS

A review of congenital diaphragmatic hernias was performed for the period between January 1991 and August 2000. Repair types included primary repair, synthetic patch, or a split abdominal wall muscle flap. The split abdominal wall muscle flap is performed by downward rotation of the internal oblique and transversalis abdominal wall muscles. This repair requires that the initial subcostal incision be positioned at least 4 to 5 cm below the costal margin, low enough to insure an adequate length of muscle will be available to fill the defect.

RESULTS

Eight of 158 children with congenital diaphragmatic hernia underwent repair by abdominal wall muscle flap. Five of 8 had complete agenesis. Five survived the newborn period. Of the survivors, 4 of 5 required an additional surgical procedure, but none have had a recurrent hernia.

CONCLUSIONS

The split abdominal wall muscle flap is an effective technique to close large diaphragmatic hernias. The repair was carried out successfully in 8 patients with massive defects. In the surviving patients, the repair has proven to be a durable restoration of the diaphragm.

Artificial lungs: a new inspiration

An estimated 16 million Americans are afflicted with some degree of chronic obstructive pulmonary disease (COPD), accounting for 100,000 deaths per year. The only current treatment for chronic irreversible pulmonary failure is lung transplantation. Since the widespread success of single and double lung transplantation in the early 1990s, demand for donor lungs has steadily outgrown the supply. Unlike dialysis, which functions as a bridge to renal transplantation, or a ventricular assist device (VAD), which serves as a bridge to cardiac transplantation, no suitable bridge to lung transplantation exists. The current methods for supporting patients with lung disease, however, are not adequate or efficient enough to act as a bridge to transplantation. Although occasionally successful as a bridge to transplant, ECMO requires multiple transfusions and is complex, labor-intensive, time-limited, costly, non-ambulatory and prone to infection. Intravenacaval devices, such as the intravascular oxygenator (IVOX) and the intravenous membrane oxygenator (IMO), are surface area limited and currently provide inadequate gas exchange to function as a bridge-to-recovery or transplant. A successful artificial lung could realize a substantial clinical impact as a bridge to lung transplantation, a support device immediately post-lung transplant, and as rescue and/or supplement to mechanical ventilation during the treatment of severe respiratory failure.

Extracorporeal membrane oxygenation for severe respiratory failure

The use of extracorporeal technology to accomplish gas exchange with or without cardiac support is based on the premise that "lung rest" facilitates repair and avoids the baso- or volutrauma of mechanical ventilator management. Extracorporeal membrane oxygenation (ECMO), a modified form of cardiopulmonary bypass, has been shown to decrease mortality of neonatal, pediatric and adult respiratory failure and is capable of total gas exchange. In neonates, over 20,638 patients have been treated with an overall survival of 77% in a population thought to have 78% mortality.

Surgical embryology and anatomy of the diaphragm with surgical applications

This article reviews the development, surgical anatomy, and teratology of the diaphragm, and discusses the diagnostic procedures, surgical therapy, and prognosis of congenital disturbances. Special attention is paid to the traumatic rupture of the diaphragm, concerning incidence, cause, diagnosis, prognosis, and surgical repair.

Current surgical management of congenital diaphragmatic hernia: a report from the Congenital Diaphragmatic Hernia Study Group

BACKGROUND

Repair of congenital diaphragmatic hernia (CDH) has changed from an emergent procedure to a delayed procedure in the last decade. Many other aspects of management have also evolved since the first successful repair. However, most reports are from single institutions. The lack of a large multicenter database has hampered progress in the management of congenital diaphragmatic hernia (CDH) and makes determination of the current standard difficult.

METHODS

The CDH study group was formed in 1995 to collect data from multiple institutions in North America, Europe, and Australia. Participating centers completed a registry form on all live-born infants with CDH during 1995 and 1996. Demographic information, data about surgical management, and outcome were collected for all patients.

RESULTS

Sixty-two centers participated, with 461 patients entered. Overall survival was 280 of 442 patients (63%) where survival was recorded. The defect was left-sided in 78%, right-sided in 21%, and bilateral in 1%. A subcostal approach was used in 91% of patients, with pleural drainage used in 76%. A patch of some kind was used in just over half (51%) of the patients, with polytetrafluoroethylene being the most commonly used material (81%) in those patients with a patch. The mean surgical time was 102 minutes, with an average blood loss of 14 mL (range, 0 to 500 mL). The overwhelming majority of patients underwent repair between 6:00 AM and 6:00 PM (289 of 329, 88%). Nineteen percent of patients had surgical repair on extracorporeal membrane oxygenation (ECMO) at a mean time of 170 hours into the ECMO course (range, 10 to 593 hours). The mean age at surgery in patients not treated with ECMO was 73 hours (range, 1 to 445 hours).

CONCLUSIONS

The multicenter nature of this report makes it a snapshot of current management. The data would indicate that prosthetic patching of the defect has become common, that after-hours repair is infrequent, and that delayed surgical repair has become the preferred approach in many centers. Furthermore, the mean survival rate of 63% indicates that despite decades of individual effort, the CDH problem is far from solved. This highlights the need for a centralized database and cooperative multicenter studies in the future.

Survival of patients with congenital diaphragmatic hernia during the ECMO era: an 11-year experience

BACKGROUND/PURPOSE

Congenital diaphragmatic hernia (CDH) is associated with significant mortality and morbidity. To evaluate the impact of extracorporeal membrane oxygenation (ECMO) on survival, a review of our experience with CDH patients was initiated.

METHODS

The authors performed a retrospective nonrandomized analysis of 98 consecutive CDH patients who were ECMO candidates, and were symptomatic within the first day of life, and underwent repair between May 1985 and May 1996. The patients were divided into three groups: Group 1 (n = 38) refers to patients who were clinically stable and underwent repair before 48 hours of age and did not need ECMO rescue; Group 2 (n = 29) consists of patients who underwent repair but required ECMO rescue; and Group 3 (n = 31) refers to patients who met ECMO criteria preoperatively and required ECMO for stabilization and later underwent repair on ECMO. The Kaplan-Meier survival graph was used for survival analysis.

RESULTS

During the 11-year span, the overall survival rate of all CDH patients was 72% (71 of 98). The survival rate of patients who did not require ECMO support was 92% (35 of 38), whereas patients who required ECMO after repair had a 72% (21 of 29) survival rate. These were compared with a 48% (15 of 31) survival rate for those undergoing repair on ECMO. The differences in survival among the three groups were statistically significant using the log-rank test (P = .0018).

CONCLUSIONS

Survival was significantly better for infants who underwent successful repair without ECMO than those who required ECMO rescue pre- or postrepair. The overall improved survival of CDH patients to 72% compared with historical controls of 38% to 58% may be attributed to ECMO, but the requirement of ECMO before repair, as well as the presence of congenital anomalies (P < .01), prematurity (P < .01), the need for a Gore-Tex patch at repair (P < .05), prenatal diagnosis at less than 25 weeks' gestation (P < .01), and the occurrence of an intracranial hemorrhage (P < .01), decreases the chances of survival.

Congenital diaphragmatic hernia--a tale of two cities: the Boston experience

Infants with congenital diaphragmatic hernia (CDH) show a wide range of anatomic and physiological abnormalities, making it difficult to compare the efficacy of management protocols between institutions. The purpose of this study was twofold: (1) to analyze the results of treatment of CDH in a large tertiary care pediatric center using conventional mechanical ventilation (CMV) with extracorporeal membrane oxygenation (ECMO) as rescue therapy, and (2) to compare these results with those of a parallel study by a similar large urban center that used high-frequency oscillating ventilation (HFOV) as rescue therapy without ECMO. All patients who had CDH diagnosed within the first 12 hours of life and were referred for treatment before repair (between 1981 and 1994) were included in the analysis (n = 196). CMV was used initially in all patients, with conversion to ECMO for refractory hypoxemia or hypercapnea. Between 1981 and 1984, ECMO was not available. Between 1984 and 1987, ECMO was offered postoperatively. Between 1987 and 1991, ECMO was offered preoperatively. In all three groups, aggressive hyperventilation and alkalosis was the norm. Since 1991, permissive hypercapnia has been used. HFOV was used in three patients as stand-alone therapy with one survivor. Twenty patients died without repair: Ten had other lethal anomalies, eight died before ECMO could be instituted, and two died of ECMO-related complications. Overall, 104 patients (53%) survived and 92 (47%) died. Ninety-eight patients (50%) received ECMO, and 43 (44%) survived. Survivors had significantly higher 1- and 5-minute Apgar scores and higher postductal Po2s than did nonsurvivors. Associated anomalies were present in 39%, who had a significantly lower survival than those with isolated CDH. Antenatal diagnosis and side of the defect had no impact on outcome. Survival was not improved with the institution of ECMO or delayed repair but rose significantly to 69% (84% with isolated CDH, P = .007) with the introduction of permissive hypercapnea. Autopsy results from nonsurvivors showed other lethal anomalies and significant barotrauma as the primary causes of death. Comparisons between the Boston and Toronto series showed similar patient demographics and no significant differences in survival in any time period. The two series differed in the number of associated anomalies, their impact on survival, and in the prognosis of right-sided CDH. From the individual and combined analyses the authors concluded: (1) CMV with ECMO as rescue produced an overall survival in CDH patients equivalent to CMV with HFOV in a parallel series, (2) neither HFOV nor ECMO has significantly improved outcome in CDH patients, (3) institution of permissive hypercapnia has resulted in a significant increase in survival, and (4) the leading causes of death in CDH patients appear to be associated anomalies and pulmonary hypoplasia, which are currently untreatable. Barotrauma, which may contribute in up to 25% of deaths in CDH patients is avoidable.

Prenatal diagnosis of congenital diaphragmatic hernia and pulmonary hypoplasia and therapeutic strategy

The outcome of fetuses with congenital diaphragmatic hernia (CDH) has been reported to be fatal when pulmonary hypoplasia (PH) is severe. As an indicator of PH, we attempted to measure the lung-thorax transverse area ratio (L/T) using ultrasonic echography. Immediate postnatal surgery was performed using high-frequency oscillatory ventilation (HFOV) and sometimes followed by extracorporeal membrane oxygenation (ECMO). Eighteen fetuses were treated and 14 survived. L/T correlated well with the best preductal arterial blood gas data before surgical reduction during manual ventilation and HFOV, while preductal PO2 and alveolar-arterial oxygen differences from patients managed with HFOV were better than those in patients with manual ventilation. Although L/T also correlated with the duration of O2 therapy and hospitalization in survivors without major anomalies, there was no significant difference between L/T in survivors and nonsurvivors. Because delayed institution of ECMO and complications related to ECMO management seemed to be a major cause of death in non-survivors, the unsalvageable L/T due to PH was estimated to be below 0.06 for HFOV and below 0.1 for conventional ventilation based on the correlation between L/T and preductal P02. These results suggest that L/T is a useful indicator of PH in patients with CDH and also that HFOV is advantageous in treating CDH with PH. The advantage of prenatal diagnosis in predicting unsalvageable L/Ts, should be considered in the therapeutic strategy.

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

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

Hemorrhagic complications and repair of congenital diaphragmatic hernias: does timing of the repair make a difference? Data from the Extracorporeal Life Support Organization

The authors reviewed the Extracorporeal Life Support Organization (ELSO) data base of all neonates placed on extracorporeal membrane oxygenation for whom CDH was diagnosed between January 1989 and December 1991. For 483 neonates, there were complete data concerning timing of the hernia repair in relation to ECMO. The overall incidence of hemorrhage was 43% (57% among nonsurvivors, 32% among survivors; P < .05). The most common bleeding sites were surgical repair site (24%), head (11.5%), cannulation site (7.5%), and gastrointestinal (5%). Fatal hemorrhage occurred in 4.8% (23 of 483). The most common sites of fatal hemorrhage were head (48%), pulmonary (17%), and abdominal (17%). Bleeding complications were significantly greater for patients repaired on ECMO (58%) versus those repaired before (37%) or after (21%) (P < .05). Surgical-site hemorrhage requiring transfusion occurred in 38% of those repaired on ECMO versus 18% and 6% of those repaired before and after, respectively (P < .05). Gastrointestinal and "other" sites of hemorrhage were significantly more common in those repaired on bypass. The number of patients repaired on ECMO increased from 22% to 48% over the 3 years (P < .05). The incidence of hemorrhagic complications did not differ significantly among the 3 years (P > .05). Repair of the hernia defect while on bypass was associated with significantly greater bleeding complications. These data should be useful in the planning of future prospective trials.