Development of an Outpatient Native Kidney Biopsy Service in Low-Risk Patients: A Multidisciplinary Approach

Abstract

Background: In the US, native kidney biopsies are usually inpatient procedures. We developed an outpatient biopsy protocol for low-risk patients and assessed its safety and efficacy. Methods: Patients with an SBP <140 mm Hg and a BMI ≤35 who were not taking anticoagulants, ASA and NSAIDS in the preceding week were included. Biopsies were performed under ultrasound guidance using a 15-gauge needle that changed to a 14-gauge needle during the study. Patients were discharged after 5 h of observation if there were no signs of bleeding. Complications were carefully recorded. Results: Between November 2008 and April 2011, 105 patients underwent outpatient renal biopsies. A 15-gauge needle was used in 43 patients (group A) while a 14-gauge needle was used in 62 (group B). A median of 25 (range 4–64) glomeruli were obtained in group A versus 39 (range 0–107) in group B (p < 0.001). Complications requiring admission for observation occurred in 7 patients (16%) in group A versus 5 patients (8%) in group B (p = 0.22). One patient in group B had bleeding requiring intervention, while all other complications were minor. Nine complications occurred during the observation period, while 3 patients presented >48 h after biopsy. The mean cost per patient for each outpatient biopsy was USD 976 versus USD 5,489 for inpatients. Conclusions: In a selected low-risk population, outpatient renal biopsy is safe with low complication rates and results in significant cost savings relative to elective inpatient biopsies. The use of a 14-gauge biopsy needle resulted in a greater yield of glomeruli without increased complications.