Pre-donation assessment of kidneys by magnetic resonance angiography and venography: accuracy and impact on outcomes

Hypertension and renal outcomes in normotensive kidney donors with multiple renal arteries

Having multiple renal arteries (MRA) has been linked to hypertension development. Whether kidney donors who are left with MRA in the nondonated kidney incur a higher risk of hypertension has not been studied. We compared the development of hypertension, reduced estimated glomerular filtration rate (eGFR), cardiovascular disease, and mortality in 2624 normotensive kidney donors with MRA in the nondonated kidney and to 2624 propensity score matched normotensive donor controls with a single renal artery. In total, 35% of donors had MRA. Donors with MRA were less likely to have undergone a left nephrectomy (51% vs. 83%). Postdonation hypertension was associated with age, male gender, non-White ethnicity, obesity, and family history of hypertension. Having MRA was not associated with risk of hypertension; aHR 0.92 (95% CI 0.82-1.03), P = 0.16. After 17 ± 11 years from donation, a similar proportion of donors with and without MRA developed cardiovascular disease, proteinuria and eGFR <30, <45 and <60 mL/min/1.73 m² and the multivariable risks of developing these outcomes were similar in the two groups. Our study did not show increased risk for hypertension, reduced eGFR, proteinuria or cardiovascular disease in donors with MRA in the remaining kidney and without hypertension at donation.

Perioperative Complications During Living Donor Nephrectomy: Results From a Multicenter Cohort Study

BACKGROUND

While living kidney donation is considered safe in healthy individuals, perioperative complications can occur due to several factors.

OBJECTIVE

We explored associations between the incidence of perioperative complications and donor characteristics, surgical technique, and surgeon's experience in a large contemporary cohort of living kidney donors.

DESIGN

Living kidney donors enrolled prospectively in a multicenter cohort study with some data collected retrospectively after enrollment was complete (eg, surgeon characteristics).

SETTING

Living kidney donor centers in Canada (n = 12) and Australia (n = 5).

PATIENTS

Living kidney donors who donated between 2004 and 2014 and the surgeons who performed the living kidney donor nephrectomies.

MEASUREMENTS

Operative and hospital discharge medical notes were collected prospectively, with data on perioperative (intraoperative and postoperative) information abstracted from notes after enrollment was complete. Complications were graded using the Clavien-Dindo system and further classified into minor and major. In 2016, surgeons who performed the nephrectomies were invited to fill an online survey on their training and experience.

METHODS

Multivariable logistic regression models with generalized estimating equations were used to compare perioperative complication rates between different groups of donors. The effect of surgeon characteristics on the complication rate was explored using a similar approach. Poisson regression was used to test rates of overall perioperative complications between high- and low-volume centers.

RESULTS

Of the 1421 living kidney donor candidates, 1042 individuals proceeded with donation, where 134 (13% [95% confidence interval (CI): 11%-15%]) experienced 142 perioperative complications (55 intraoperative; 87 postoperative). The most common intraoperative complication was organ injury and the most common postoperative complication was ileus. No donors died in the perioperative period. Most complications were minor (90% of 142 complications [95% CI: 86%-96%]); however, 12 donors (1% of 1042 [95% CI: 1%-2%]) experienced a major complication. No statistically significant differences were observed between donor groups and the rate of complications. A total of 43 of 48 eligible surgeons (90%) completed the online survey. Perioperative complication rates did not vary significantly by surgeon characteristics or by high- versus low-volume centers.

LIMITATIONS

Operative and discharge reporting is not standardized and varies among surgeons. It is possible that some complications were missed. The online survey for surgeons was completed retrospectively, was based on self-report, and has not been validated. We had adequate statistical power only to detect large effects for factors associated with a higher risk of perioperative complications.

CONCLUSIONS

This study confirms the safety of living kidney donation as evidenced by the low rate of major perioperative complications. We did not identify any donor or surgeon characteristics associated with a higher risk of perioperative complications.

TRIAL REGISTRATIONS

NCT00319579: A Prospective Study of Living Kidney Donation (https://clinicaltrials.gov/ct2/show/NCT00319579)NCT00936078: Living Kidney Donor Study (https://clinicaltrials.gov/ct2/show/NCT00936078).

Assessment of the arteries in living kidney donors: correlation of magnetic resonance angiography with intraoperative findings

Comprehensive imaging evaluation of kidney donor anatomy is crucial for selecting candidates for living kidney transplantation and for determining the surgical technique to procure the renal graft. In 76 living renal donors we compared the results of preoperative magnetic resonance angiography (MRA) with the intraoperative findings of arterial anatomy. Donors were evaluated for the number of main renal arteries and the presence of any polar arteries. A total of 80 main renal arteries and five polar arteries were observed at MRA. At surgery, 90 main renal arteries and eight polar arteries were identified. MRA demonstrated a sensitivity, specificity, and overall accuracy of 18%, 98%, and 87%, respectively, for main arteries and 25%, 96%, and 88% for polar arteries. Eleven (14.5%) kidneys displayed more than one main artery and MRA only detected two cases. Eight kidneys had polar arteries and MRA only detected two cases. MRA is a reliable method for presurgical evaluation of renal arteries in potential donors, providing valuable information required by the surgeon. But, as the technique misses small-diameter vessels, it cannot be recommended as the sole diagnostic tool in unclear cases.