Matthew D Whealon, MD, Juan J Blondet, MD, Michael J Phelan, PhD, Ninh T Nguyen, MD. UC Irvine
Introduction: There is no published data regarding the relationship between hospital volume and outcomes in patients undergoing laparoscopic diaphragmatic hernia repair. We hypothesize that centers performing high case volume have improved outcomes compared to low volume centers.
Materials and Methods: We reviewed the National Inpatient Sample (NIS) database between 2008 and 2012 of adults with the diagnosis of Diaphragmatic Hernia (ICD-9 code 5533) who underwent elective laparoscopic repair of diaphragmatic Hernia (5371) and/or Nissen fundoplication (4467). Pediatric, emergent, and open cases were excluded. Main outcome measures include in-hospital mortality, serious morbidity, length of stay, and the association between case volume and in-hospital mortality.
Results: During the study period, a total of 31,228 laparoscopic diaphragmatic hernia operations were performed. The overall in-hospital mortality was 0.14%. Risk factors for mortality were age older than 60 years (OR 5.05 (2.38-10.76), 95% CI; p<0.0002) and renal failure (OR 6.26 (2.48-15.78), 98% CI; p<0.0009). Risk factors for serious morbidity were age older than 60 years (OR 2.14 (1.63-2.82), 95% CI; p<0.0001), renal failure (OR 5.01 (3.11-8.07), 95% CI; p<0.0001), and congestive heart failure (OR 5.77 (3.67-9.07), 95% CI; p<0.0001). There was an inverse relationship between higher hospital case volume and lower mortality with an annual threshold volume of 10 cases per year. Using this threshold volume, low volume hospital (£10 cases) has a significantly higher mortality compares to high volume hospitals (0.23% vs 0.12%, respectively).
Conclusions: Laparoscopic diaphragmatic hernia repair is associated with low in-hospital mortality. Significant risk factors for in-hospital mortality and serious morbidity were older age, renal failure, and congestive heart failure. There is an inverse association between the centers’ case volume and mortality with an annual threshold case volume of 10 cases.