Does Glomerular Filtration Rate at Discharge After Partial Nephrectomy Predict Long-Term Glomerular Filtration Rate Stability?

J Endourol. 2019 Jun;33(6):488-491. doi: 10.1089/end.2018.0869. Epub 2019 May 10.

Abstract

Introduction: Being able to predict glomerular filtration rate (GFR) plateau after partial nephrectomy (Pnx) is an important goal in providing patients with a confident projection of maintained renal function. As such, in an ethnically and socioeconomically diverse, inner city cohort of patients undergoing Pnx, we compared preoperative (pre-op) and day of discharge (DC) GFR to that of long-term GFR measured at 12-18 months to evaluate postoperative (post-op) GFR stability. Methods: A total of 162 patients who had undergone minimally invasive Pnx at a single institution between 2010 and 2016 were reviewed. Patients with the following available measurements were included: pre-op GFR, DC GFR, and long-term GFR (12-18 months after DC). Multivariate linear regression was performed to assess factors predictive of long-term GFR, including estimated blood loss, warm ischemic time, tumor size, length of stay, pre-op GFR, DC GFR, race, chronic kidney disease, diabetes mellitus, and hypertension. Results: Mean pre-op GFR, DC GFR, and long-term GFR were 70.754, 68.326, and 66.526 mL/(minute ·1.73 m2), respectively. Mean GFR change was -4.228 pre-op to long term and -1.800 DC to long term. No significant difference was observed between means of DC GFR and long-term GFR (p = 0.248) as well as between means of pre-op GFR and DC GFR (p = 0.062). A significant difference was observed between pre-op GFR and long-term DC GFR (p = 0.002). On multivariate analysis, both pre-op GFR (β = 0.532; 95% confidence interval [CI] = 0.256-0.808; p ≤ 0.001) and DC GFR (β = 0.312; 95% CI = 0.089-0.537; p = 0.007) were found to be strong predictors of long-term GFR (R2 = 0.608). Conclusions: Long-term GFR in a highly ethnically diverse inner city population recovering from Pnx is stable relative to GFR measured at DC from the hospital. Our findings demonstrate that patients experience a GFR plateau after surgery, resulting in minimal change in renal function at a mean of 14 months post-op.

Keywords: GFR; partial nephrectomy; renal function.

MeSH terms

  • Aged
  • Diabetes Complications
  • Female
  • Follow-Up Studies
  • Glomerular Filtration Rate*
  • Humans
  • Hypertension / complications
  • Kidney Neoplasms / complications
  • Kidney Neoplasms / surgery*
  • Linear Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Nephrectomy*
  • Nephrology / standards
  • Patient Discharge
  • Postoperative Period
  • Renal Insufficiency, Chronic / complications
  • Retrospective Studies
  • Social Class
  • Treatment Outcome
  • Warm Ischemia