Risk Factors and Timing of Native Kidney Biopsy Complications

Abstract

Background: The appropriate observation period, rate and risk factors of complications after a percutaneous renal biopsy remain debated. Methods: We retrospectively studied native kidney biopsies performed in our institution between January 2007 and July 2011. Outpatients had either an 8- (67%) or a 24-hour (33%) observation period. Results: 312 biopsies were reviewed (287 patients), 51% of patients were female and the mean age was 54 ± 15 years. Half of these biopsies were performed in outpatients. A total of 15% of patients developed a symptomatic hematoma, 9% received a red blood cell transfusion and 1% required an angio-intervention. Eighty-four percent of the complications manifested within the first 8 h, 86% at 12 h and 94% at 24 h. Outpatients experienced significantly less complications, all manifesting within the first 8 h, 14% required an observation period longer than planned. The risk of symptomatic hematoma increased to 11, 20, 35 and 40% in patients with >200, 140-200, 100-140 and <100 × 10⁹/l platelets, respectively (p = 0.002). It also increased in hemodialysis patients (29% compared to 14%, p = 0.02). We found no association of risk with the number of biopsy passes and only a trend with needle size. Conclusion: Symptomatic hematomas occurred in 15% of kidney biopsies and were strongly associated with platelet count and hemodialysis. Outpatients experienced fewer complications; therefore, we can conclude that same-day discharge in selected patients is safe.

The Native Kidney Biopsy

“…Although the overall incidence of requiring a blood transfusion in this meta-analysis was 0.9% (95% confidence interval, 0.4% to 1.5%), transfusion rates as high as 5%-9% have been described in large single-center case series from major academic centers (7,12,(35)(36)(37). This may be because of some PRBs being performed by nephrology trainees and more high-risk patients undergoing PRBs at large academic centers.…”

“…Whittier and Korbet (42) found that 67% of major complications (need for transfusion or invasive procedure, acute renal obstruction or failure, septicemia, or death) occurred during the first 8 hours of observation, with 91% detected by 24 hours and 9% detected after 24 hours. In a smaller retrospective series, Simard-Meilleur et al (36) found that 100% of complications in outpatients undergoing PRB occurred within 8 hours versus 72% of complications in inpatients and that 10% of inpatients had complications .24 hours after PRB. The most recent large biopsy series found that 91% of major complications occurred within 12 hours of PRB, with 7.4% occurring between 12 and 24 hours and 1.85% occurring after 24 hours (43).…”

Safety of Outpatient Kidney Biopsies

“…In the outpatient setting, it is important to know the timing of complications to determine the optimal post-biopsy observation period. In a study form France [18], 100% of complications occurred in outpatients within 8 h vs. 72% complications in inpatients, and 10% of inpatients had complications >24 h after biopsy. Historical data, prior to real-time US guidance, recommended longer observation periods [19].…”

Renal Parenchymal Thickness as a Predictor of Post Percutaneous Kidney Biopsy Complication

“…Another large retrospective study conducted in Norway identified low platelet as the most important single risk factor in predicting post-procedural bleeding. Interestingly, lower bleeding risk was reported to be associated with outpatient procedure [9]. So far, rare research has focused on the structural effect of the biopsied kidneys on the bleeding risk.…”