537. ASSESSING THE EFFECT OF HIATAL HERNIA SIZE ON PERIOPERATIVE OUTCOMES AND HOSPITAL READMISSION RATES AFTER PRIMARY REPAIR

Abstract Background Minimally invasive hiatal hernia (HH) repair remains the gold standard for correcting mechanical defects due to its safety and favorable clinical outcomes (i.e., relief of patient symptoms). However, several operative factors, including the HH size, may negatively impact the postoperative course. We aimed to determine if an increase in HH size was related to an increased risk of perioperative complications or hospital readmissions. Methods After IRB approval, we performed a retrospective analysis using a prospectively maintained database containing demographic, perioperative, and clinical data from all patients who underwent HH repair by a single experienced foregut surgeon between September 2016 and July 2023. Four groups were defined based on the proportion of stomach at the thoracic cavity determined during the surgery: A (small HH: <25%), B (moderate HH: 25-49%), C (large HH: 50-74%), and D (intrathoracic stomach [ITS]: ≥75%). Non-parametric tests were used to assess differences between the groups, and logistic regressions were used to determine the relevant odds ratios (OR). Results A total of 391 patients who underwent primary HH repair met the inclusion criteria (73.7% women; mean age 64.4±12.5 years; mean BMI 28.9±4.9 kg/m2). The distribution of groups was: A (n=160, 40.9%), B (n=63, 16.1%), C (n=64, 16.4%), and D (n=104, 26.6%). Patients presenting with ITS (group D) were older, had longer operative duration, greater blood loss (p<.001), and a significantly increased risk of presenting with early postoperative complications (OR 2.78 [CI95: 1.52-5.06]) and being admitted to the ICU (OR 12.35 [CI95: 3.41-44.71]). Conclusion The HH size, defined by the proportion of the stomach at the thoracic cavity, is associated with an increased risk of early postoperative complications and ICU admission; moreover, a trend toward higher 30- and 90-day hospital readmission rates was noted. This factor may be a consequence of the progressive nature of the disease; hence, it should be considered when choosing between continued medical observation and surgical treatment of patients presenting with asymptomatic HH. An early intervention may reduce the risk of postoperative comorbidity.