J. B. Melendez2, S. Manz4, M. Cramer3, A. Kanters1, J. B. Dimick1, D. A. Telem1 1University Of Michigan,Department Of Surgery,Ann Arbor, MI, USA 2University Of Michigan,Medical School,Ann Arbor, MI, USA 3Cornell University,Ithaca, NY, USA 4University Of Michigan,Ann Arbor, MI, USA
Introduction: Numerous studies demonstrate that ultrasound use in diagnosing inguinal hernias is unwarranted. Despite this, ultrasonography is liberally utilized as part of the workup for this condition. To address this practice gap, we sought to understand provider practice patterns and the impact of ultrasound on patient management.
Methods: A single-center, retrospective chart review of 522 patients who presented to the division of minimally invasive surgery from 1/2014-4/2017 was performed. Following the exclusion of patients with a recurrent inguinal hernia, 358 charts were evaluated. Data for patients with and without ultrasound were compared via univariate analysis. Significant variables were then analyzed through multivariate regression models
Results: Of the 358 patients evaluated for an inguinal hernia, 131 (36.6%) had an ultrasound examination of which 121 (93.1%) ultrasounds were positive for hernia. Women (p=0.002) and persons younger than 40 (p=0.01) were significantly more likely to undergo ultrasound. Ultrasounds were ordered most frequently by primary care providers in internal and family medicine (76.5%). Only 2.3% of ultrasounds were ordered by surgeons. The physical exam performed by the ordering provider was available for 87% of patients who underwent an ultrasound, and a positive hernia exam was documented in 44.7%. For patients who did not undergo ultrasound, 82.9% had a positive pre-surgical referral clinical exam (data available for 72.9%). Hernia detection rates on physical exam did not differ between surgeon and referring/ordering provider. A total of 187 patients underwent surgery, of which 54 had an ultrasound and 134 did not. All but 1 patient had a hernia per the operative records. For those with positive physical exams, recommendation for operative intervention did not differ between patients with and without an ultrasound (75.3% vs. 79.1%, p=0.5). Similarly, recommendation for operative intervention did not differ between patients with and without an ultrasound and a negative clinical exam (14.8% vs. 7.7%, p=0.37). For the 8 (14.8%) patients with an ultrasound and negative physical exam who went to surgery, 6 had positive and 2 had negative ultrasounds for hernia.
Conclusion: Ultrasound is used as a diagnostic tool in nearly 40% of patients with a primary inguinal hernia, without a clear impact on patient care. Presence of a positive ultrasound did not change patient management, and decisions for operative intervention were predominantly guided by physical exam. The majority of ultrasounds were ordered by providers in a primary care setting. The decision to order an ultrasound appears multifactorial, particularly as nearly half of patients who underwent ultrasound had a documented positive physical exam by the ordering provider. Further work to understand individual provider behavior is needed to develop effective strategies aimed at de-implementation of ultrasound use for inguinal hernia diagnosis.