Long-term compensation of renal function after donor nephrectomy

Clinical predictors associated with prolonged pneumoperitoneum time in laparoscopic living donor nephrectomy

BACKGROUND

Kidney transplantation (KT) is a useful treatment option for patients with end-stage chronic kidney disease to avoid dialysis and achieve a good quality of life. In Japan, approximately 90% of kidneys for KT are obtained from living kidney donors. Laparoscopic renal nephrectomy (LDN) is the most commonly performed KT procedure in Japan. We aimed to determine the clinical variables that influence the prolongation of pneumoperitoneum time (PT) in LDN.

METHOD

This retrospective study was carried out on 218 consecutive patients who underwent LDN at Gifu University Hospital. T The enrolled patients were divided into two groups according to the third quartile of PT in the LDN, with those in the lower third quartile (Q3) as Group 1 and those in the upper Q3 as Group 2. The primary endpoint was identification of predictive factors for prolonged PT.

RESULT

In total, 178 patients were included in the analysis. For all patients, the median PT, estimated blood loss, and warm ischemic time were 170 min, 20 mL, and 4 min, respectively. Significantly longer PT was observed in Group 2 than in Group 1. Multiple regression analysis results showed that male donors, body mass index ≥ 25 kg/m2, and donors with more than two renal arteries were independent predictive factors for PT prolongation.

CONCLUSION

Male sex, BMI ≥ 25 kg/m2, and two or more renal arteries are predictive factors for prolonged PT for donors in LDN.

Predicting new-baseline glomerular filtration rate (NBGFR) after donor nephrectomy: validation of a split renal function (SRF)-based formula

BACKGROUND

Accurate prediction of post-donor nephrectomy (DN) glomerular filtration rate is potentially useful for evaluating and counselling living kidney donors. Currently, there are limited tools to evaluate post-operative new-baseline glomerular filtration rate (NBGFR) in kidney donors. We aim to validate a conceptually simple formula based on split renal function (SRF) previously developed for radical nephrectomy patients.

METHODS

Eighty-three consecutive patients who underwent DN from 2010 to 2016 were included. Pre-operative CT imaging and functional data including pre-DN baseline Global GFR (108.2 ± 13.2 mL/min/1.73m2) were included. Observed NBGFR was defined as the latest eGFR 3-12 months post-DN. SRF, defined as volume of the contralateral non-resected kidney normalised by total volume of kidneys, was determined from pre-operative cross-sectional imaging (49.2 ± 2.36%). The equation derived from Rathi et al. is as detailed: Predicted NBGFR = 1.24 × (Global GFR Pre-DN) x (SRF).

RESULTS

The relationship between predicted NBGFR (66.0 ± 8.29 mL/min/1.73m2) and observed NBGFR (74.9 ± 16.4 mL/min/1.73m2) was assessed by evaluating correlation coefficients, bias, precision, accuracy, and concordance. The new SRF-based formula for NBGFR prediction correlated strongly with observed post-operative NBGFR (Pearson's r = 0.729) demonstrating minimal bias (median difference = 7.190 mL/min/1.73m2) with good accuracy (96.4% within ± 30%, 62.7% within ± 15%) and precision (IQR of bias =  - 0.094 to 16.227).

CONCLUSION

The SRF-based formula was also able to accurately discriminate all but one patient to an NBGFR of > 45 mL/min/1.73m2. We utilised the newly developed SRF-based formula for predicting NBGFR in a living kidney donor population. Counselling of donor post-operative renal outcomes may then be optimised pre-operatively.

Risk factors for lower renal compensation after nephrectomy: an analysis of living kidney donors in an Amazonian cohort

INTRODUCTION

Living donor kidney transplantation is considered the ideal renal replacement therapy because it has a lower complication rate and allows an efficient response to the high demand for grafts in the healthcare system. Careful selection and adequate monitoring of donors is a key element in transplantation. Individuals at greater risk of developing kidney dysfunction after nephrectomy must be identified.

OBJECTIVE

To identify risk factors associated with a renal compensation rate (CR) below 70% 12 months after nephrectomy.

METHODS

This observational retrospective longitudinal study included living kidney donors followed up at the Lower Amazon Regional Hospital between 2016 and 2022. Data related to sociodemographic variables, comorbid conditions and kidney function parameters were collected.

RESULTS

The study enrolled 32 patients. Fourteen (43.75%) had a CR < 70% 12 months after kidney donation. Logistic regression found obesity (Odds Ratio [95%CI]: 10.6 [1.7-65.2]), albuminuria (Odds Ratio [95%CI]: 2.41 [1.2-4.84]) and proteinuria (Odds Ratio [95%CI]: 1.14 [1.03-1.25]) as risk factors. Glomerular filtration rate was a protective factor (Odds Ratio [95% CI]: 0.92 [0.85-0.99]).

CONCLUSION

Obesity, albuminuria and proteinuria adversely affected short-term renal compensation rate. Further studies are needed to uncover the prognostic implications tied to these risk factors. Our findings also supported the need for careful individualized assessment of potential donors and closer monitoring of individuals at higher risk.