Trends in emergent inguinal hernia surgery in Olmsted County, MN: a population-based study

Evidence suggests that watchful waiting of inguinal hernias (IH) is safe because the risk of acute strangulation requiring an emergent repair is low. However, population-based incidence rates are lacking, and it is unknown whether the incidence of emergent inguinal hernia repairs (IHR) has changed over time.

A retrospective review of all IHR performed on adult residents of Olmsted County, Minnesota from 1989 to 2008 was performed using the Rochester epidemiology project, a record-linkage system that covers more than 97 % of the population (2010 US Census = 146,466). Incidence rates/100,000 person-years were calculated, and trends over time were evaluated using Poisson regression.

A total of 4,026 IHR were performed on 3,599 patients; 136 repairs (3.8 %) were emergent. Of these, 19 patients (14 %) had bowel resection and three (2 %) died within 30 days of the repair. Rates/100,000 person-years yielded an overall incidence of 7.6 for emergent IHR and 200.0 for elective IHR. Emergent IHR rates increased with age. Overall emergent IHR rates declined from 18.2 to 12.4 in men and from 6.4 to 2.4 in women from 1989 to 2008 (p > 0.05). Older age, obesity, a high ASA risk score, a femoral and/or a recurrent hernia were more likely to be associated with an emergent IHR (all p ≤ 0.05).

The incidence of emergent IHR is low. This risk has decreased over the past 20 years. However, patients who are either ≥70 years old, obese, with a high ASA score, or with a femoral or recurrent hernias are more likely to require an emergent IHR and could benefit from elective operative intervention if deemed adequate surgical candidates.