Anterior fundoplication at the time of congenital diaphragmatic hernia repair

Significant GER can be an impediment to early establishment of full oral feedings. Nasogastric tubes and drip feedings as part of the medical management only complicate the establishment of eventual oral feedings. Included in the spectrum of defects associated with CDH are anatomic abnormalities of the esophagus and stomach predisposing to GER. These include a small, vertically oriented stomach, an obtuse angle of His and the lack of an intra-abdominal esophagus [4, 17]. Fundoplication performed at a later stage for recalcitrant symptoms is often difficult secondary to adhesions, the presence of a synthetic patch and abnormal positioning of the spleen and liver. Therefore, we elected to perform a low morbidity primary anti-reflux procedure to optimize early oral feedings and assist the management of GER in infants with high-risk anatomy [7‐10, 15].

A 360° gastric fundoplication may be difficult at the time of CDH repair due to insufficient fundus to wrap around the esophagus. We selected the Boix-Ochoa anti-reflux procedure for its principle of establishing normal anatomic barriers, the utility in infants with small stomachs [7, 15] and its relative ease, particularly without the crural dissection. In this population, the crura are often weak and fragile and dissection adds time and can increase the morbidity of the anti-reflux procedure, without improving GER. To date, none of the infants developed a hiatal hernia, supporting the decision to avoid crural dissection.

Data are lacking in literature regarding the use of anti-reflux procedures at the time of CDH repair and results were conflicting regarding factors that predict future development of GER. Kieffer et al. [9] reported the preoperative thoracic position of the stomach as a risk factor for GER . With the use of a multivariate model, Diamond et al. showed that the position of the liver within the chest and need for patch closure were positive predictors of future GER [18]. These reports are supportive of the concept of regional mediastinal development abnormalities in CDH. Other investigators also found that infants undergoing patch repair have a greater likelihood of developing GER [2, 5]. However, Koot et al. [3] could not demonstrate a positive relationship between the size of the defect and GER. Fashing et al. [19] could not show an association between GER and thoracic position of the stomach, abnormal position of the liver or the use of a patch.

Based on the above data, it is difficult to predict which infants are at high-risk for developing GER. Nevertheless, in recent reports, the most commonly reported association of GER after CDH repair is in infants with the severest form of pulmonary hypoplasia due to large defects [5, 17, 20]. In our series, the average day of life consistent with maximal resolution of pulmonary hypertension was 11 days, and two neonates required ECMO rescue prior to being stable for diaphragm repair. These neonates comprise a group with severe to moderate disease and would thus be expected to be at high risk for GER.

The anatomic criteria we used for patient selection for concomitant anterior fundoplication (absence of an intra-abdominal esophagus, an obtuse angle of His and a small, and/or a vertically oriented stomach), although not specifically studied in a cohort of infants with CDH, have been well documented and studied to be associated with GER [7, 9, 10, 15, 21‐24]. DeMeester et al. were the first to indisputably demonstrate the need for having an adequate length of intra-abdominal esophagus to have an anti-reflux valvular effect [21, 22]. When the angle of His is obtuse, it is converted into a funnel such that the stomach contents are easily directed to the esophagus. In 1986, Bardaji et al. [10] demonstrated with a series of in vivo experiments in dogs that only at very high intra-gastric pressures reflux occurs if the angle of His is acute. In addition, Thor et al. [24] demonstrated similar findings in human cadavers that an obtuse angle of His was associated with reflux. Recreation of the angle of His has also been described to be beneficial as part of Nissen fundoplication as well [23]. Finally, in the case of microgastria, a full fundoplication is not anatomically possible as there is an inadequate amount of fundus to wrap around the esophagus. In such cases, the Boix-Ochoa operation is well tolarated [15].

The final selection was determined by the anatomic criteria of loss of normal barriers to GER. The primary outcome of this study was discharge on oral feedings, which we were able to achieve in 8/10 surviving neonates and one other infant was only on partial NG feedings due to oral aversion. The subsequent need for Nissen fundoplication was eventually seen in 2/10 infants. Of note, Nissen fundoplication was deferred for 18 months in both children, during which time oral feedings were possible. None of the neonates whom we deemed not to have high-risk anatomy required anti-reflux surgery later in life, suggesting that our anatomic selection criteria have merit. After including these 15 surviving neonates who did not undergo anterior fundoplication, the incidence of conversion to Nissen is only 2/25 (8%) in our population.

Our non-randomized experience performing a previously unreported combination of anterior fundoplication and CDH repair allows us to conclude that an anterior fundoplication to restore anatomy can be quick and without morbidity [7, 15]. In addition, anterior fundoplication appears to improve post-operative oral feeding. A modified fundoplication should therefore be considered in the operative management of high-risk infants. Future randomized trials may be conducted to determine the efficacy of this procedure.