RENAL FUNCTION AND ADAPTIVE CHANGES AFTER RADICAL OR PARTIAL NEPHRECTOMY: A SINGLE CENTRE STUDY

Abstract

Suraj Godara1, Harish Gupta2, Shameer Deen3, T. C. Sadasukhi4, Manish Gupta5, H. L. Gupta6

OBJECTIVES

To study the renal function before partial or total nephrectomy and to study change in renal function and adaptive change in the retained kidney after partial or total nephrectomy. Place and Duration: The prospective study of 40 patients was conducted by the Dept. of Nephrology and Dept. of Urology, Mahatma Gandhi Medical College and Hospital, Jaipur from July 2012 to July 2014

METHODS

The data for the study was obtained from all the patients undergoing nephrectomy at Mahatma Gandhi Medical College and Hospital, in the study duration. 20 patients from the donor nephrectomy group and 20 from nephrectomy group were considered. Open Nephrectomy was performed by a lumbar incision in all 40 patients. After tracheal intubation and general anaesthesia, the nephrectomy was performed through an incision under the left or right costal margin. GFR of both kidneys before surgery and of the unilateral retained kidney were determined in each subject using the Tc-99m DTPA Scans. Donors underwent the first follow-up at 1 month after surgery and then at 6 months and 1 year after surgery. The follow-up included measurements of blood pressure, urinary protein, serum creatinine, and GFR of the retained kidney by Tc-99m DTPA scan as well as volume of the retained kidney by ultrasound examination.

RESULTS

A total number of 80 patients were included in this study. In donor group female to male ratio was 4:1 and in disease group male to female ratio was 3:1. Maximum no. of patients was of age group 50-60 years in both groups, with mean age of 44.8±6.7 years in donor group and 48.7±5.5 years in disease group. In disease group majority patients who underwent nephrectomy were suffering from RCC. Th98ere was no significant effect on blood pressure, haemoglobin, blood sugar level, urine pH., urine specific gravity after nephrectomy in both groups. In both groups 24-hour urine protein increased from preoperative level to 11.3% in donor group and 17.1% in disease group after 6 month of nephrectomy. There was initial rise of serum creatinine in both donor (23.5% increase) and disease group (18.8% increase) at 1 month. After 6 month in there was decline in percentage increase of serum creatinine in both donor (15.2%) and disease group (14.3%). GFR was raised significantly at 1 month in both donor (29.4% increase) and disease (16.1% increase), but after 6 month it stabilized in both donor (31.5%) and disease (17.2%) group. Kidney volume increased significantly at 1 month in both donor (21.5% increase) and disease (13.3% increase) group and it stabilizes after 6 month in both donor (22.3%) and disease (14.8%) groups. Age has a significant effect on post nephrectomy rise of GFR. In donor group young age group (<50 yrs.), GFR increased to 35.6% at 1 month and upto 38.4% after 6 months. Old age group (>50 yrs.), GFR increased to 26.9% at 1 month and 28.2% after 6 month of donation. Gender and BMI did not have a significant effect on both the groups

CONCLUSION

After unilateral nephrectomy, the morphology, structure function, and hemodynamic parameters of the retained kidney show adaptive compensatory changes, that stabilized by 6 months. The compensatory changes included elevated GFR and ERPF in the retained kidney, increased kidney volume. Age, preoperative creatinine level, and HTN were statistically significant predictive factors affecting the change in GFR after unilateral nephrectomy. In present study showed that the compensatory change in the GFR of the remaining kidney declined with increasing age in both the younger donors and older nephrectomy groups. Although the follow-up period in this study was limited to 1 year after nephrectomy, the results reveal that even patients with normal GFR levels should be followed for more than 1 year to determine the fate of renal function after nephrectomy.

image