Multi-Institution Case Series of Pediatric Patients with Laparoscopic Repair of Morgagni Hernia

Introduction

Congenital diaphragmatic hernias develop due to impaired fusion and/or development of the diaphragm and costal arches.^1,2 Morgagni Larray hernia (MLH) is characterized by anterior herniation of abdominal organs, most commonly liver, intestine, and omentum, through the anterior retrosterno-costal angle.^3,4 A rare disease, MLH incidence is ∼1 out of 4800 live births and accounts for less than 5% of all congenital diaphragmatic hernias.^2,5,6 MLH can be asymptomatic and is often found incidentally. The most common presenting symptoms in the pediatric population are respiratory distress and infections or gastrointestinal discomfort. MLH may also be associated with heart defects and Down syndrome.

Pediatric patients diagnosed with MLH typically undergo surgical repair to treat the condition. Historically, an open approach was the only possible treatment for these patients. The introduction of minimally invasive techniques (such as laparoscopy) have resulted in a faster recovery time and equal success rates, and minimal morbidity and mortality.^7,8

Since MLH is a rare disease, there are very few studies in the literature, especially from Latin America. The purpose of this study is to describe the outcomes, reproducibility, and morbidity of patients with MLH, which were repaired laparoscopically in the pediatric population.

Materials and Methods

A retrospective study of patients diagnosed with MLH treated with a laparoscopic approach by board-certified pediatric surgeons was performed in nine different Mexican institutions from 2013 to 2017. Patients who were not operated on laparoscopically (i.e., open approach) were excluded.

All patients underwent general anesthesia. The patient was placed in the decubitus position and a pneumoperitoneum was created by open or closed technique. Three ports were used for laparoscopy: one (5 or 10 mm) in the superior umbilical scar and one (3 or 5 mm) on each iliac fossa at the middle clavicular line. With the surgeon at the feet of the patient (with separated legs) and the monitor at the head, the abdominal cavity was explored and visceral material was extracted from the hernia. The hernia sac was then dissected with a monopolar hook under extreme caution to avoid damaging surrounding structures such as the mediastinum or pleural cavity. Once the sac was completely resected, closure of the defect was performed with extracorporeal full thickness U-stitches (nonabsorbable suture) anchoring to the bone or cartilage tissue from the ribs, xiphoid, or aponeurosis. Some colleagues (70%) did not resect the sac and directly closed the defect.

Patient data, including age, gender, socioeconomic status, initial presentation, laterality, hernia sac presence, other associated malformations, and radiologic findings, were collected for every patient. Surgical technique, operating room (OR) time, follow-up, recurrences, and initiation of feeding time were also analyzed.

Results

A total of 14 patients diagnosed with MLH, who underwent a laparoscopic repair, were included in this study. The median age of diagnosis was 13.5 months (interquartile [IQ] 8.75–24.5). All, but one of these patients (92.86%) were male (Table 1). Thirteen patients were diagnosed incidentally. Overall, 9 patients had associated respiratory (88.89%) or abdominal symptoms (11.11%) at the time of diagnosis. Seven patients came from a low socioeconomic household (50%), 6 from medium (42.86%), and 1 from high (7%). Eight patients (57.14%) had Down syndrome. We also found that 7 patients had an associated comorbidity, including minor heart defects (42.86%) such as interauricular and interventricular communication and patent conductus arteriosus, cryptorchidism (14.29%), intestinal malrotation (14.29%), and anorectal malformation (14.29%). Over half (64.29%) of the patients studied had multiple radiologic tests to confirm the diagnosis. Chest X-ray confirmed diagnosis in 71.43% of the patients, followed by a contrast enema (64.29%). Three patients (21.43%) had an esophagogastroduodenal series and computed tomography scan. One patient had an ultrasound (7.14%) performed.

All the patients were approached through the abdomen. A hernia sac was present in 100% of cases, and 6 (42.86%) were resected. A total of 8 cases were bilateral (57.1%), 3 were present on the left side (21.43%) and 3 on the right (21.43%). Most cases (78.57%) were closed without a mesh. The colon was the most frequent organ found inside the defect (71.43%), followed by small intestine (57.14%) and liver (7.14%). The preferred instrument port size was 5 mm (71.43%), followed by 3 mm (28.57%). All defects were closed with a nonabsorbable suture: polyester (50%), polypropylene (28.57%), and silk (21.43%). There were no conversions to an open surgery nor complications reported during surgery. Median OR time was 90 minutes (IQ 65–120). Oral feeds were initiated within the first 12 hours postoperatively in 14.29% of the patients, in 71.43% of patients within 48 hours, and in 14.29% of patients after 48 hours (Table 2).

Follow-up was available for a majority (92.86%) of the patients because 1 patient died 1 month after surgery due to respiratory complications unrelated to the surgery. The remaining patients were followed for a median of 1.75 years (IQ 0.3–6.95). There was a single recurrence in a patient with partial resection of the sac, which was repaired without a mesh. He was reoperated laparoscopically without mesh and without recurrences up to date. Success rate overall was 92.86% (Table 3).

Discussion

Congenital diaphragmatic hernias are infrequent, with MLH being the least common. Currently, the incidence of congenital diaphragmatic hernias is unclear due to a variation of incidence worldwide. While there are several retrospective case series of patients, with MLH that had been repaired laparoscopically,^2,5,8,9 this is the first study from Latin America to add information regarding outcomes of laparoscopic hernia repair in patients with this pathology. It is difficult to prospectively study the outcomes of patients in Latin America diagnosed with MLH that is treated laparoscopically due to its low incidence.

In our series, there was a higher frequency of bilateral MLH (57%) than unilateral (21%). Interestingly, of those unilateral hernias, there was an equal number of right and left hernias, despite left-sided hernias being traditionally less frequent due to pericardial attachments at the diaphragm conferring protection and support. In a study by Al-Salem et al., the majority of MLH they encountered (41.5%) were on the right, while only 28.3% were found on the left.^8,10 They also found a high frequency of bilateral hernia (30.2%). In contrast, Golden et al. reported nearly the same frequency of left-sided (19.2%) and right-sided (23.1%) hernias and a very low number of patients with bilateral hernia (7.7%). In their series, the most common location of the hernia was at the midline (50%). It is still unknown why there is a very high incidence of bilateral hernia in this population. In most cases, the presence of an empty sac at the time of repair resulted in the diagnosis of a bilateral hernia, which is also supported by our study.^8,10

Patients with MLH may have variable symptoms or be asymptomatic until adulthood. In our series, we found respiratory infection and associated symptoms (88.89%) to be the most common presenting symptoms in this patient population, followed by vague abdominal discomfort (11.11%). The majority of these patients were diagnosed incidentally (92.86%) due to workup for mild respiratory symptoms (cough, rhinorrhea, and upper respiratory infection). Our data support the findings of other authors and establish that the most common presenting symptoms are respiratory followed by gastrointestinal.^2,4,10,11

It is extremely important to suspect a congenital diaphragmatic hernia in a patient with a history of recurrent respiratory infections, especially in patients with a chromosomal abnormality, such as Down syndrome. Trisomy 21 has been linked to MLH with rates of more than 30% by many series.^1,4,9,12 In our cohort, 57.14% of patients had Down syndrome. Also, 71.43% of the patients who had an associated malformation had Down syndrome, of which 60% were minor heart defects. As mentioned by other groups, heart defects (interauricular and interventricular communication) are the most common associated malformations in these patients.^1,4,9 We highly suggest to initiate workup and look for MLH abnormalities in chest X-rays of patients with recurrent respiratory infections and Down syndrome.

There are two repair options for patients with MLH: open or laparoscopic. Previous studies comparing open versus laparoscopic repair have demonstrated equal outcomes with nearly 100% of success rates.^2,8,10,13 There are several advantages of performing a laparoscopic repair: better visualization, more space for dissection and instrumentation, and all the benefits of a minimally invasive surgery, including: less pain, decreased postoperative hospitalization, and better cosmesis. When performed laparoscopically, resection of the sac is not necessary, which decreases operative time and surgical complexity.^2,14,15 In our study, we had a success rate of 92.86% after MLH laparoscopic repair. There was 1 patient who had a recurrence and was repaired laparoscopically without recurrence up to date. This patient also had Down Syndrome and initially had a partial revision of the sac. This mirrors the experience of Al-Salem et al., who noted that the only recurrence they experienced was on a patient who was repaired without a mesh and had Down syndrome. ¹⁰ It has been hypothesized that patients with Down syndrome have generalized hypotonic muscles predisposing to the development of hernias and/or predisposition to future recurrences.

We are well aware that due to the low incidence and rarity of MLH, there are limitations to studying this pathology. Hence, our retrospective study design is limited to obtaining extent analysis of the benefits of laparoscopic repair. We will pursue to study this pathology prospectively in the future as well as including more institutions from Mexico and other Latin American countries. There is also the possibility of a reporting bias. Most of the pediatric surgeons who participated in this study do not have experience in performing laparoscopy for repairing MLH, and technique variations may be a confounding factor. Even though this is not a common procedure, treating other pathologies laparoscopically (appendectomy and cholecystectomy) conferred enough surgical skills to provide the surgeon adequate exposure of anatomy and repair of the defect with intracorporeal or extracorporeal suturing in patients with MLH. Resection of the sac does not alter significantly the outcome of the patient, which is advantageous for pediatric surgeons with little technical experience in laparoscopy.

MLH is a rare congenital diaphragmatic hernia that is usually diagnosed incidentally due to nonspecific respiratory or gastrointestinal symptoms in the pediatric population. Laparoscopic repair of the hernia defect has high success rates and is a viable option for patients with this pathology. We encourage pediatric surgeons to use this approach as it does not need extra specific training abilities besides standard laparoscopic skills.