Discussion
Although epigastric hernias in children are common,2 3 23 they are only mentioned incidentally in seminal works24 and textbooks of pediatric surgery,25 26 while there is an official clinical guideline for the adult population.6 For children with epigastric hernias, there are only limited clinical data available from cohorts with small sample sizes. A recent systematic review identified only 81 children since the 1960s,3 which is surprising for a condition that accounts for 4%–6% of all pediatric hernia repairs.1 2
As in the systematic review,3 preschool children were the common age group for pediatric epigastric hernia in our cohort, although others noted another peak in infants1 2 or older children,23 which might represent a different preference for the timing of surgery.3 Similar to preceding reports,2 3 the majority of children in our series presented with asymptomatic swelling, while localized pain was the major complaint in 30% of the included patients. This finding corroborates previous reports with 38%2 and 31%3 of patients experiencing localized pain. As reported before,2 3 the majority of cases occurred in the midline of the abdomen, whereas paramedian epigastric hernias were rare. Preceding research reported the fascial defects to be small with a median of 3 mm3 and a mean of 7 mm,2 while we found a median fascial defect size of 5 mm that was even larger in supraumbilical hernias with a median of 10 mm. Larger defect sizes of up to 25 mm have been described,2 and we noticed a maximum defect size of 20 mm in our series in a 2-year-old girl. In our series, nine patients had fascial defects of 10 mm or more.
At the opposite site of the spectrum, there are those patients with small fascial defects: due to the difficulty of palpating them, it has been advised to regularly mark the site of the hernia preoperatively, as it may be difficult to identify it in the supine and relaxed patient.2 3 We have been able to establish this association using correlation analyses and indeed found that small fascial defects are much less likely to be found during clinical examination. The palpable fascial defect is not a prerequisite to make the diagnosis: the diagnosis is mainly established by the presence of a (para)median swelling in physical examination.3 27 The aspect of the palpable fascial defect is relevant because the swelling will often disappear in the operating room, but this can be addressed by preoperative marking of the localization of the swelling before induction of anesthesia.2 3 Consequently, the use of ultrasound in pediatric epigastric hernia has been debated: some considered it to be exceptional, as the clinical examination will almost always establish the diagnosis,3 while others assumed ultrasound to be useful to establish the diagnosis because in the majority of cases, the fascial defect was not detected without ultrasound.4 Ultrasound has been a valuable tool in the evaluation of abdominal wall hernias for decades,28 and due to its high sensitivity and specificity, it may be advantageous when the clinical examination is equivocal.29 The most relevant among these is the differentiation between umbilical hernias and supraumbilical hernias7: ideally, epigastric hernia could easily be discerned from umbilical hernias due to a distance to the navel as exemplified by Tinawi and Stringer3 or due to a characteristic U shape of the umbilicus being pushed downward by the epigastric hernia as shown by Shastri and Gilmer.30 If the clinical examination alone could not allow differentiation between these two types of hernia, ultrasound would most likely do so. This differentiation in equivocal cases is also of clinical relevance, as the management differs: while epigastric hernias are usually scheduled for elective repair once diagnosed,2 3 watchful waiting for spontaneous closure for asymptomatic umbilical hernia until the age of 4 years has been recommended by a systematic review.31 In addition, in umbilical hernias, the defect size is associated with the odds of spontaneous closure, with larger defects being less likely to close spontaneously,32 so the information gained by ultrasound could even be of relevance for counseling the patient’s family if an umbilical and not an epigastric hernia is diagnosed. However, ultrasound should not be part of the routine care for epigastric hernia, as it is recommended to refer patients to secondary pediatric surgical care anyway if an epigastric hernia is suspected.33
In our series, four (7%) patients presented only with a history of swelling but neither a palpable fascial defect nor reproducible swelling in the clinical examination. There might be a role for parental photographs to confirm the presence of an epigastric hernia, either as a virtual diagnosis34 or if a mass is not palpated on clinical examination. Ultrasound may play a limited role in preoperative localization in cases where a mass cannot be palpated. In this case, ultrasound would reliably identify the fascial defect and thus enable the preoperative marking of the level of the fascial defect. One may also argue that these children might rather be observed until the hernia becomes apparent, but one of the affected children in our series was symptomatic with abdominal pain, so observation would not have been indicated, as is commonly described in seminal works.24 Moreover, it has been described that fascial defects in children tend to enlarge during observation or become symptomatic,2 but additional data on the natural progress of epigastric hernias are missing in children.3 In addition, many kids will find rubbing of the hernias against their clothes irritating.2 33 In addition to these aspects, it must be taken into account that epigastric hernias might have a relevant risk of non-elective repair, which would be accompanied by an increased anesthetic risk. As the literature and subsequently the opinions of pediatric surgical departments assessed by Tinawi and Stringer3 are divided on the point of whether asymptomatic epigastric hernias should be repaired, some recommend it,2 4 7 33 while others prefer watchful waiting,13 27 we counsel the parents on both treatment options, but usually, in our experience, the parents will opt for the operative repair.
Although our study is the first to include both laparoscopic and open epigastric hernia repairs, it cannot be seen as a comparative study. A relevant portion of the laparoscopic hernia repairs were conducted in patients with specific circumstances, such as multiple epigastric hernias, concomitant repair of an incisional hernia or other simultaneous operations. Therefore, the number of comparable cases is just too small to derive a reliable result in the comparison of both techniques. Nevertheless, having both techniques within one cohort indicates that laparoscopy might indeed be beneficial if there are multiple defects7 or concomitant procedures to be undertaken, while we generally favored the open approach if a single epigastric hernia was to be repaired.
In addition to the retrospective nature of our study, a further limitation is that we cannot provide the direly needed3 long-term data on the spontaneous course of an epigastric hernia and the risk of recurrence following epigastric hernia repair, particularly in children with larger fascial defect sizes. Another limitation of our study is a portion of missing clinical data in several patients, which is common in all reports of pediatric epigastric hernias2 3 and thus not specifically caused by poor documentation in our centers. Administrative data might be helpful in covering these issues, although the currently available reports did not assess recurrences1 or did explicitly exclude them by their study design.23 Another limitation is that the use of ultrasound was different between the two study centers, which is likely to have introduced additional bias besides the one that is caused by the treating pediatric surgeon deciding whether an ultrasound should be conducted or not.
To date, our study represents the largest cohort of epigastric hernias in children, increasing the available information in the literature by more than 50%. In addition, due to the routine use of ultrasound in one of the two study sites and infrequently in the other study site, our study was able to provide further insight into the role of ultrasound in pediatric epigastric hernias. Its use might be beneficial in patients in whom an epigastric hernia cannot be diagnosed clinically or if a preoperative marking of the level of the hernia was impossible, as preceding research demonstrated that point-of-care ultrasound in the operating room will reliably detect the fascial defect.35 However, outside this limited range of indications, ultrasound for pediatric epigastric hernia is not a necessity for diagnosis or management and would put an undue burden on radiology departments if ordered routinely.35 Consequently, the treating pediatric surgeon, who will see the child because a referral to secondary care is recommended,33 should decide whether an ultrasound examination of an epigastric hernia is necessary.