Prosthetic materials and muscle flaps in the repair of extensive diaphragmatic defects: an experimental study

Hemorrhage after on-ECMO repair of CDH is equivalent for muscle flap and prosthetic patch

BACKGROUND/PURPOSE

Prosthetic patch (patch) and muscle flap (flap) techniques are utilized for severe congenital diaphragmatic hernia (CDH) repair; however, when performed on extracorporeal membrane oxygenation (ECMO), the risk of hemorrhage increases. We sought to compare bleeding complications between repair types.

METHODS

We retrospectively reviewed 2010-2016 on-ECMO CDH repairs.

RESULTS

Twenty-nine patients met criteria: 13 patch (44.8%) and 16 flap (55.2%). Eight patch (61.5%) and 13 flap (81.2%) patients had left-sided defects (p = 0.223). All defects were Type C or D (Type C: patch 53.8%, flap 56.2%, p = 0.596). There was no difference in gestational age at delivery (patch 37.5 ± 0.9 weeks, flap 37.2 ± 1.3 weeks, p = 0.390) or age at repair (patch 7.46 ± 6.6 days, flap 6.00 ± 4.3 days, p = 0.476). Seven patch (53.8%) and 9 flap (56.2%) patients survived to discharge (p = 0.596). Estimated intraoperative blood loss was equivalent (patch 35.3 ± 53.9 mL, flap 24.2 ± 18.4 mL, p = 0.443). One patch patient (7.6%) and two (12.5%) flap patients required reoperation in the first 48 h for bleeding (p = 0.580). 48-h postoperative transfusions were the same for those that required reoperation (patch 282.0 mL/kg, flap 208.5 ± 21.9 mL/kg, p = 0.054) and those that did not (patch 120.7 ± 111.7 mL/kg, flap 118.4 ± 89.9 mL/kg, p = 0.561).

CONCLUSIONS

On-ECMO bleeding complications are equivalent for both flap and patch CDH repair.

LEVEL OF EVIDENCE

Type III (retrospective comparative study).

Diaphragmatic hernia repair using a rectus abdominis muscle pedicle flap in three dogs

Objective: To report the clinical use of a pedicle flap from the rectus abdominis muscle to repair extensive diaphragmatic tears in dogs with diaphragmatic hernia.

Materials and methods: Three dogs with a combination of radial and circumferential diaphragmatic tears were studied. The circumferential tear was repaired by suturing the wound edge with the edge at the abdominal wall. A pedicle flap of the rectus abdominis muscle was used for repairing the radial tear. The dogs were examined radiographically for lung and diaphragm appearance and evidence of reherniation at 10 days, and at one, two, and four months after surgery, and fluoroscopically for paradoxical motion of the diaphragm at one and four months.

Results: The rectus abdominis muscle pedicle flap was successfully used in all three dogs. The animals recovered uneventfully without evidence of reherniation during the four follow-up months. Fluoroscopic examination revealed no paradoxical motion of the diaphragm.

Clinical significance: A rectus abdominis muscle pedicle flap can be used for repairing large diaphragmatic defects in dogs.

New insight in the biological integration of polytetrafluoroethylene from an explant used for diaphragm repair

Congenital diaphragmatic hernia is a severe disease requiring diaphragm replacement mostly with expanded polytetrafluoroethylene. Unfortunately, the recurrence rate is high due to prosthesis failure with significant morbidity for the child. To provide a better understanding of the integration and possible failure processes of the biomaterial implanted in humans, we conducted electron microscopical and mechanical assessments on a prosthesis explant from a child with congenital diaphragmatic hernia presenting a recurrence. Our findings show a major penetration of connective tissue into the expanded polytetrafluoroethylene on the rough side, whereas the smooth side presents few tissue colonization. This penetration is more important in the central area (area A) with large collagen bundles and layers, in comparison to the peripheral areas without prosthesis failure (area B), where few extracellular matrix is produced. The connective tissue penetrates the prosthesis in depth. In contrast, the peripheral areas with prosthesis failure (area C) show very few cells and extracellular matrix, with an oriented organization in comparison to areas A and B. Obviously, the forces applied on the implanted material modulate the cellular behavior of the newly developed tissues. Atomic force microscopic measurements of the biomaterials’ surfaces may explain some cellular behaviors according to areas with or without failure.

Organ bioengineering for the newborn

Regenerative medicine has recently been established as an emerging interdisciplinary field focused on the repair; replacement or regeneration of cells, tissues and organs. It involves various disciplines, which are focused on different aspects of the regeneration process such as cell biology, gene therapy, bioengineering, material science and pharmacology. In this article, we will outline progress on tissue engineering of specific tissues and organs relevant to paediatric surgery.

Diaphragmatic muscle reconstruction with an aligned electrospun poly(ε-caprolactone)/collagen hybrid scaffold

Large diaphragmatic muscle defects in congenital diaphragmatic hernia (CDH) are reconstructed by prosthetic materials or autologous grafts, which are associated with high complications and reherniation. In this study we examined the feasibility of using aligned electrospun poly(ε-caprolactone) (PCL)/collagen hybrid scaffolds for diaphragmatic muscle reconstruction. The hybrid scaffolds were implanted into a central left hemi-diaphragmatic defect (approximately 70% of the diaphragmatic tissue on the left side) in rats. Radiographic and magnetic resonance imaging (MRI) analyses showed no evidence of herniation or retraction up to 6 months after implantation. Histological and immunohistochemical evaluations revealed ingrowth of muscle tissue into the scaffolds. The mechanical properties of the retrieved diaphragmatic scaffolds were similar to those of normal diaphragm at the designated time points. Our results show that the aligned electrospun hybrid scaffolds allowed muscle cell migration and tissue formation. The aligned scaffolds may provide implantable functional muscle tissues for patients with diaphragmatic muscle defects.

A review of patch options in the repair of congenital diaphragm defects

Repair of congenital diaphragmatic hernia (CDH) continues to pose a dilemma for the pediatric surgeon. While the management of CDH has evolved from surgical urgency to delayed repair after medical optimization with substantial improvements in mortality, morbidity continues to perplex clinicians. Significant morbidity occurs with recurrence, re-recurrence and complications such as obstructions, principally with mesh repair. When primary closure is not possible, mesh repair is indicated. While there are several non-absorbable prosthetic, absorbable biosynthetic and composite mesh types available, the ideal mesh remains elusive. In this article, we reviewed the current materials, reported advantages, and animal and clinical studies of non-absorbable prosthetic, absorbable biosynthetic and composite mesh. However, adequate comparative data are lacking, leaving a wide void for future animal models and clinical studies.

Reconstruction of a large diaphragmatic defect in a kitten using small intestinal submucosa (SIS)

A double-layer sheet of small intestinal submucosa (SIS) was used to reconstruct a large chronic diaphragmatic defect in a 4-month-old kitten. The SIS graft was easy to use, postoperative recovery was uneventful, no side effects of the SIS implant were observed, and the SIS graft resulted in restoration of normal clinical function while allowing growth of the kitten without restriction of chest wall development. Herniation of fat through the caval hiatus was diagnosed 29 months postoperatively on a CT scan. The cat was free of clinical signs.

Evaluation of diaphragmatic hernia repair using PLGA mesh-collagen sponge hybrid scaffold: an experimental study in a rat model

Patch closure is necessary to achieve tension-free repair in large congenital diaphragmatic hernia. However, the use of prosthetic material may lead to granulation, allergic reaction, infection, recurrence of hernia, and thoracic deformity. Tissue engineering may become an alternative treatment strategy for diaphragmatic hernia repair, since the regenerated autologous tissue is expected to grow potentially without rejection or infection. We evaluated the efficacy of diaphragmatic hernia repair in a rat model using a poly-lactic-co-glycolic acid (PLGA) mesh-collagen sponge hybrid scaffold, designed for in situ tissue engineering. Twenty-four F344 female rats were used. Oval-shaped defects were surgically created in the left diaphragm and repaired with three different grafts, including PLGA mesh in group 1 (n = 7), PLGA mesh-collagen sponge hybrid scaffold in group 2 (n = 7), and PLGA mesh-collagen sponge hybrid scaffold seeded with bone marrow-derived mesenchymal stem cells (MSCs) in group 3 (n = 10). The animals were killed at 1, 2, and 3 months after operation. The specimens were examined macroscopically and microscopically. No recurrence or eventration was observed. In all animals, autologous fibrous tissue with vascularization was generated at the graft site. Although no muscular tissue was detected, scattered desmin-positive cells were observed in groups 2 and 3. The 'neodiaphragm' in groups 2 and 3 was significantly thicker compared with that in group 1. There was no significant difference in the 'neodiaphragm' between groups 2 and 3. The PLGA mesh-collagen sponge hybrid scaffold provided better promotion of autologous in situ tissue regeneration in the diaphragm, suggesting its potential application to diaphragmatic repair in place of other prosthetic patches.

Rejection of goretex mesh used in prosthetic cruroplasty: a case series

INTRODUCTION

In recent years prosthetic cruroplasty with PTFE has been advocated as the optimal way to reduce hernia recurrence when repairing large hiatal hernia. However, we have found in our series a significant incidence of rejection and mesh erosion.

MATERIALS AND METHODS

Standard, tension-free ePTFE hiatal hernia repair was performed in 15 patients with large hiatal hernia. Three of these patients subsequently went on to develop complications with the mesh. Here we present these cases: 2 females and 1 male aged 84, 66 and 69 years, respectively. Each underwent prosthetic hiatal hernia repair using dual goretex mesh. After 7, 12, and 34 months each of the cases presented with dysphagia.

RESULTS

In all three of these cases initial endoscopy revealed narrowing at the lower end of the oesophagus, with inflammatory changes and erosion. In two of the cases, the mesh was noted to have eroded into the distal oesophagus, and in the third case relaparoscopy showed a peri-oesophageal collection including the mesh surrounded with fibrosis. Each of the complications was managed using minimally invasive techniques. In one instance the eroded mesh was removed by endoscopy without further complication. While in the second, due to the patient's age and comorbidities the eroded mesh was left in-situ and a covering stent was endoscopically sited. In the case of the peri-oesophageal collection, this was drained laparoscopically and the mesh was removed, with the patient making an excellent recovery. In each instance the patient's dysphagia was corrected and there was no recurrence of the hiatus hernia.

CONCLUSIONS

We conclude by acknowledging that in spite of the fact that Gore-Tex (ePTFE) is currently being recommended as one of the choice materials for the prosthetic reconstruction of the hiatus. Our experience suggests that it should be used with great caution in the peri-oesophageal region.

Prosthetic esophageal erosion after mesh hiatoplasty in a child, removed by transabdominal endogastric surgery

Although there is evidence in the adult surgical literature to suggests that the use of mesh prosthesis during laparoscopic hiatal hernia repair results in much reduced recurrence rates, there remains a real potential for esophageal and gastric mesh erosion. A 12-year-old boy presented with esophageal obstruction from an eroded polytetrafluoroethylene prosthesis used to buttress a hiatal hernia repair 9 years earlier. A laparoscopic endogastric approach was used to remove the mesh. Great caution must be exercised in the decision to use mesh for hiatal hernia repair in children who must live with such a prosthesis for a lifetime and risk erosion. Mesh should be reserved only for those children who have extremely large defects with no chance of primary closure and for those with recurrent hernias and friable crural tissue. In all cases, the family must be informed of the potential for eventual erosion. Removal of eroded mesh using minimal access techniques can be simple and effective.

Hemidiaphragmatic reconstruction with a transversus abdominis muscle flap after resection of a solitary diaphragmatic mesothelioma in a dog

CASE DESCRIPTION

A 2-year-old Siberian Husky was evaluated because of a 2-week history of coughing and gagging and decreased appetite and activity level.

CLINICAL FINDINGS

Radiography, surgery, and immunohistochemical examination revealed a solitary sclerosing mesothelioma extending from the left thoracic diaphragmatic surface that was adherent to the pericardium and the caudal mediastinum.

TREATMENT AND OUTCOME

The tumor was resected along with most of the left hemidiaphragm, and the left transversus abdominis muscle was used to reconstruct the diaphragm. The 13th rib formed the base of the muscle flap. The muscle flap was transposed into the defect so that the mesothelium-lined surface faced the thoracic cavity and the deep aspect of the muscle formed the abdominal surface of the diaphragm. To minimize risk of adhesions, the exposed raw aspect of the abdominal surface was covered with porcine small intestinal submucosa. Recovery was uncomplicated, and the dog's appetite and activity level soon returned to normal. Evaluation 54 days after surgery revealed 2 subcutaneous masses on the thorax and masses in the liver and both kidneys; histologic and immunohistochemical analyses revealed metastasis of the original tumor. The dog was euthanatized.

CLINICAL RELEVANCE

Hemidiaphragmatic reconstruction with a transversus abdominis muscle flap after resection of a diaphragmatic tumor was successful. The muscle flap was easily harvested and transposed into the diaphragmatic defect.

Prosthetic patches for congenital diaphragmatic hernia repair: Surgisis vs Gore-Tex

PURPOSE

The sequelae of congenital diaphragmatic hernia (CDH) continue well beyond the perinatal period. Up to 50% of these patients have subsequent recurrent herniation or small bowel obstruction (SBO). A recent trend has been toward the use of bioactive prosthetic materials. We reviewed different patch closure techniques used for CDH repair at our institution and their association with these sequelae.

METHODS

A retrospective review was performed of 152 records for patients with CDH. Newborns that underwent patch repair for CDH and survived for at least 30 days were included in the analysis. Primary outcomes evaluated were recurrent herniation and SBO. Two types of prostheses were examined, Gore-Tex, an artificial material, and Surgisis, a bioactive material.

RESULTS

Twelve (44%) of 27 patients who had Surgisis repair had recurrent herniation. Seventeen (38%) of 45 patients who had a Gore-Tex repair had recurrent herniation. Two additional patients in each group presented with SBO. No significant difference in recurrent herniation rates was observed (P > .5). The time to recurrence was similar in both groups (log-rank, P = .75), with most recurrences (92% Surgisis, 76% Gore-Tex) occurring in the first year.

CONCLUSION

The rates of recurrent herniation and SBO after neonatal prosthetic patch repair of CDH were similar regardless of the prosthetic material used (Surgisis or Gore-Tex).

Abdominal muscle flap repair for large defects of the diaphragm

Repair of a large diaphragmatic defect in congenital diaphragmatic hernia (CDH) and eventration of the diaphragm (DE) is difficult, especially when this is an unexpected finding at surgery. A patch of synthetic material may not be available at short notice, especially in developing countries. We describe the repair of nine such defects by using an abdominal muscle flap comprising the transversus abdominis and internal oblique muscles based on the intercostal and subcostal vessels. Although reports of similar flap repairs have been published in the literature [1-5], these employed a subcostal incision for abdominal entry, which we believe jeopardizes the flap's vascularity. Thus, we prefer to use an upper abdominal midline incision for abdominal entry in all cases of CDH and DE.

The "diaphanous" diaphragm: a radiographic sign seen after patch repair of congenital diaphragmatic hernia in neonates

OBJECTIVE

The purpose of this study was to describe the radiographic features and etiology of the "diaphanous" (translucent) diaphragm. This sign, which, to our knowledge, has not previously been described, is a transient phenomenon seen on chest radiographs, after surgical patch repair of congenital diaphragmatic hernia.

CONCLUSION

The diaphanous diaphragm is a consequence of air trapped in the porous polytetrafluoroethylene graft that creates an intragraft radiolucency apparent on postoperative chest radiographs obtained within the first 24 hr. This radiolucency is transient and gradually disappears over the first few postoperative days as the air is replaced by granulation tissue. This sign should be recognized and not mistaken for a persistent pneumothorax after repair of a congenital diaphragmatic hernia.

Mesh Crural Repair of Large Paraesophageal Hiatal Hernias

Surgical repair is indicated in patients with paraesophageal hernias but is associated with a high recurrence rate. Our objective was to assess the safety and efficacy of mesh reinforcement of the crural closure in laparoscopic paraesophageal hernia repair. We conducted a 7-year retrospective review of all patients undergoing laparoscopic paraesophageal hernia repair with or without use of mesh. The main outcome measures were use of mesh, reason for use, age, sex, preoperative symptoms, length of operation, length of hospital stay, postoperative complications, and long-term follow-up conducted by physician interview. Twelve patients were repaired with mesh (Group A) and 12 without (Group B). Age, sex, operating time, length of hospital stay, and postoperative complications were similar in both groups. In Group A two patients required an interposition graft and ten required mesh reinforcement of the crural closure. One Group A patient developed an early recurrence requiring a reoperation, and one Group B patient developed a gastric leak where the fundus was sutured to the crura. The remainder of the patients experienced resolution of their symptoms at 2 weeks follow-up. Long-term follow-up (average 37 months) showed one Group B patient with a recurrence of reflux symptoms, but an upper gastrointestinal study showed no recurrence of hernia. All others remained asymptomatic. We conclude that the use of mesh in laparoscopic repair of large paraesophageal hernias appears safe and may reduce recurrence.

Angioleiomyoma of the diaphragm

We report a case of a large symptomatic angioleiomyoma of the diaphragm. The tumor was diagnosed by computed tomography and videothoracoscopic biopsy. We removed the tumor through a left thoracolaparotomy. Three months later, a local recurrence was removed through an upper midline laparotomy. The patient remains without evidence of a recurrence 48 months after the second operation.

Suture or prosthetic reconstruction of experimental diaphragmatic defects

OBJECTIVE

Diaphragmatic reconstruction may cause several respiratory changes. The aims of the present study were to evaluate the respiratory changes induced by two methods of diaphragmatic reconstruction.

METHODS

Two groups of rats with an experimental diaphragmatic defect were studied. In one group (n = 5), diaphragmatic resection was followed by stitching together the borders of the wound (SUT); in another group (n = 5), the defect was repaired by suturing in a polytetrafluoroethylene (PTFE) patch. All animals were sedated, anesthetized, paralyzed, and mechanically ventilated. Spirometry, respiratory mechanics, and thoracoabdominal morphometry were evaluated before and after diaphragmatic reconstruction.

RESULTS

The suture of the diaphragm significantly decreased FVC and FEV(1), and increased respiratory system, lung, and chest wall static and dynamic elastances and viscoelastic/inhomogeneous pressures in relation to their respective control values. On the other hand, diaphragmatic reconstruction with PTFE increased only respiratory system, lung, and chest wall static elastances. In addition, respiratory system, pulmonary, and chest wall viscoelastic/inhomogeneous pressures and dynamic elastances, as well as respiratory system and lung elastances, were significantly greater in SUT than in PTFE. Lateral diameter at the level of the xiphoid and cephalocaudal pulmonary diameter diminished only in the SUT group.

CONCLUSIONS

The reconstruction of the diaphragm with PTFE might be preferred to simple suture for surgical repair of large diaphragmatic defects, at least from a mechanical standpoint.

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.

Patch incorporation in diaphragmatic hernia

BACKGROUND/PURPOSE

Biomaterial insertion often is required for closure of congenital diaphragmatic hernia (CDH). The optimal biomaterial remains uncertain. This study was designed to compare a commonly used patch (polytetrafluoroethylene) with a recently available fabric, fluorinated polyester. The aim of this study was to determine the clinical performance, histological tissue-polymer interaction, bacterial adhesion, and shrinkage rates of biomaterial inserted endoscopically into a CDH lamb model.

METHODS

Polytetrafluoro-ethylene (PTFE) and fluorinated polyester (FP) were randomised for laparoscopic patch insertion into 12 lambs. All lambs (age <4 weeks) underwent 3-port laparoscopy, surgical creation of diaphragmatic hernia, and sutured patch placement. Two PTFE and 2 FP lambs were killed at 1-, 3-, and 6-month intervals postoperatively. Postmortem examination histopathology, electron microscopy, and specific bacterial broth immersion (Escherichia coil, Staphylococcus aurens, and epidermidis) were performed.

RESULTS

All 12 lambs completed the study with intact patches that were fully peritonised. One abdominal adhesion was noted in a FP lamb at 6 months. FP was comparatively easier to insert, manipulate, and suture endoscopically. Histopathology findings showed that PTFE patches created a strong peripheral foreign body reaction with dystrophic calcification, whereas FP was well incorporated with intrapatch fibroblastic activity and neovascularsation. No significant difference in resistance to bacterial adhesion of relevant organisms was noted between the materials. Graft shrinkage for FP was 7% in one direction only, evident by 3 months.

CONCLUSIONS

Fluorinated polyester has advantages in this laparoscopic lamb model. It shows rapid and sustained incorporation with intrapatch neovascularisation when compared with polytetrafluoro-ethylene's significant foreign body reaction. It was preferred for its endoscopic handling and suturing properties. The laparoscopic techniques used may contribute to the general lack of adhesions, and insufficient data are available to comment on the comparative effect of the materials on adhesion formation. No difference was demonstrated in resistance to bacterial adherence in the harvested materials.

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.

An association of pulmonary hypoplasia with unilateral agenesis of the diaphragm

During a period of 5 years, 33 newborns with congenital diaphragmatic hernia were treated. Three groups presenting with respiratory distress in the delivery room were identified. These included 8 newborns with agenesis (group 1) and 4 newborns with nonagenesis (group 2), all of whom died. There were 19 nonagenesis survivors (group 3), giving an overall survival rate of 61%. Two newborns who presented beyond 6 hours of life were excluded. No one specific arterial blood gas value or ventilation parameter obtained preoperatively could predict survival. Postmortem right and left lung weights, lung/body weight ratio, and radial alveolar counts demonstrate that agenesis is a unique subgroup with profound pulmonary hypoplasia and a dismal prognosis.

Prosthetic diaphragm reconstruction in the growing animal

Widespread use of extracorporeal membrane oxygenation (ECMO) has allowed an increasing number of infants with total agenesis of the diaphragm to survive. Polytetrafluoroethylene (PTFE) is the most widely used material for reconstruction. However, recurrent hernia is a growing problem; PTFE also does not grow with the patient. This study evaluated different materials for diaphragmatic reconstruction in growing animals. Sprague-Dawley rats with a mean weight of 93 g were anesthetized and underwent laparotomy. The control group had an incision into the diaphragm with primary repair. The other three groups underwent complete removal of the left hemidiaphragm and were randomly assigned to one of three reconstruction methods: oxidized cellulose, polyglactin mesh, or a 1-mm PTFE patch. All patch materials were sewn around the ribs circumferentially and into the membranous portion of the central diaphragm medially with 4-0 silk. Thirty-seven animals survived operation, were followed with weekly chest radiographs, and were killed when they reached 400 g. The radiographs were reviewed in a blinded fashion by two observers as were the necropsies, and rib deformity was graded on a scale of 0 to 3. Histological examination of several animals from each group was performed. There was significantly greater rib deformity (2.0 v 0.2, P < .01) in the PTFE group versus controls with 5 of 10 animals also having a smaller thorax. The PTFE pulled away from the chest wall in the animals leaving a fibrous remnant anteriorly. The polyglactin group had significantly more animals with eventration (P < .03, 7/10) compared with all others.(ABSTRACT TRUNCATED AT 250 WORDS)

ECMO and the management of congenital diaphragmatic hernia with large diaphragmatic defects requiring a prosthetic patch

From 1977 to 1991, 136 neonates have had corrective surgery for diaphragmatic hernia at Children's Hospital of Los Angeles. A retrospective study was performed to determine how many of the 136 neonates had defects large enough to require the use of a prosthetic patch to repair the defect. Twelve were found. All 12 were symptomatic at birth for respiratory distress. Mean arterial blood gas values at birth were pH 6.95, PCO2 94.8, and PO2 47.2. The mean oxygen index (n = 10) was 61.8. Six of these patients were repaired without extracorporeal membrane oxygenation (ECMO) support while the other six received ECMO bypass perioperatively. All six of the patients who did not receive ECMO support died despite successful diaphragmatic repair. Five of six patients who received ECMO perioperatively survived (83%). These surviving infants are now between 1 month and 4 years of age. In the survivors, four of five required subsequent repair and patch enlargement for a recurrent diaphragmatic hernia. Gastroesophageal reflux, requiring a Nissen fundoplication in two infants, complicated the course of three survivors. Four survivors were discharged with supplemental oxygen therapy lasting less than 13 months. Patch disruption is predicted to occur at approximately 18 months of age in all patients, especially if little or no muscle was available at primary repair for prosthetic attachment. These children should be followed closely for feeding or respiratory symptoms. Diagnosis of patch disruption can be made by chest x-rays and confirmed by contrast studies. Patch expansion by laparotomy and careful search for additional musculature for patch attachment is recommended when reherniation occurs.

Laparoscopic repair of diaphragmatic hernia

A laparoscopic diaphragmatic hernia repair was done using a left subcostal trocar insertion with a total of three ports. The laparoscopic technique was illustrated. Chest x-rays pre-op and post-op were taken. The material used in the repair was 0-Chromic sutures and expanded PTFE patch. The hospital stay was minimal (24h). The patient symptomatology was improved almost immediately. The use of a laparoscopic approach for accessible diaphragmatic hernias is the method of choice. The use of an expanded PTFE patch (with its properties to incorporate the diaphragm) adds strength to the remaining diaphragm.

Unusual varieties of diaphragmatic herniae

Unusual varieties of diaphragmatic herniae can be classified into two major groups, congenital and acquired. The late-presenting Bochdalek herniae often present difficulties in diagnosis which may lead to inappropriate treatment. The prime example is the herniated stomach, which is mistaken for a tension pneumothorax. Strangulation is a rare, but an important, complication of Bochdalek herniae. A number of techniques for closure of large diaphragmatic defects are described with recommendation of those procedures which can be performed rapidly and effectively in a critically ill infant. The literature concerning eventration is confusing due to different definitions of the condition by different authors. It may be difficult to distinguish preoperatively between this condition and congenital diaphragmatic hernia with a sac. Such distinction is often not important as the decision for intervention is based on evaluation of clinical and radiological considerations. The majority of Morgagni herniae are asymptomatic and only rarely does strangulation supervene. There is a small group of infants with Morgagni hernias who present in early infancy with respiratory symptoms. Paralysis of the diaphragm due to phrenic nerve palsy recovers spontaneously in the majority of patients. The selective use of diaphragmatic plication for this condition is widely accepted, but the decision and appropriate timing for surgical intervention is often difficult. The results of surgery are very good both in the early postoperative period and also on long-term follow-up. The diagnosis of traumatic diaphragmatic hernia is often overlooked in the presence of other major injuries. The danger of strangulation of contents of this hernia is ever present and repair should be undertaken without delay once the diagnosis is made.

Unilateral agenesis of the diaphragm

During a period of 4 1/2 years, 37 infants with congenital diaphragmatic hernia were treated. The overall survival rate was 68%. Survival depended more on cardiopulmonary function than the size of the diaphragmatic defect. There was little evidence that infants with agenesis of the diaphragm formed a special group with a poor prognosis, and four of the ten patients with unilateral agenesis survived. A Dacron prosthesis is recommended as a substitute for the missing diaphragm.