LAPAROSCOPIC VERSUS LAPAROTOMIC LIVING DONOR NEPHRECTOMY: ASSESSMENT OF GRAFT RENAL FUNCTION BY MEANS OF 99MTC-MAG3 DYNAMIC RENAL SCINTIGRAPHY

Laparoscopic living donor nephrectomy (LLDN) has been claimed to induce an increased risk of acute tubular necrosis for the transplanted kidney as compared to laparotomic living donor nephrectomy (OLDN). LLDN is characterized by longer surgery time, longer warm ischemia time, higher risk of vascular damage and vasoconstriction due to the traction on the vessels during the laparoscopic dissection and prolonged venous compression due to pneumoperitoneum. 99mTc Mag3 scintigraphy has been used to compare graft function between LLDN and OLDN groups. Material and Methods: The immediate post-operative results and the effects of the ischemic insult, in 22 grafts derived from LLDN, transplanted between 2001 to 2006, were evaluated in terms of incidence of delayed graft function (DGF), graft survival, serum creatinine and were compared with 38 grafts derived from OLDN performed between 1992 to 2006. The uptake (corrected for graft depth) of 99mTcMAG3 between first and second minute after injection, acquired on the 5th-7th postoperative day, was used to estimate effective renal plasma flow (ERPF) in both groups. Being the variables not normally distributed (shapiro wilk test), two sample Wilcoxon test (Mann Whitney) have been used to assess differences between groups. Results: Kidneys of the LLDN group suffered a mean of 160 ± 35 seconds of warm ischemia time (compared with 22 ± 11 sec in OLDN group, p<0.0001) and the mean operating time was 213 ± 36 min (vs 270 ± 41 min in the OLDN group, p<0.001). Only one PNF occurred in the LLDN group. The incidence of DGF was 4.5% in LLDN vs 2.6% in OLDN. Mean serum creatinine at 1 week post-op was 201 ± 164 in the LLDN vs 200 ± 119 µmol/L in the OLDN (p=0.49). No difference (p= 0.66) in ERPF mean values between LLDN and OLDN group was demonstrated by a twosample Wilcoxon test. Renal time concentration curve suggested tubular necrosis in 4/22 (18.2%) LLDN patients and in 4/38 (10.5%) OLDN patients. Conclusions: Despite the limited experience at our center in LLDN and the small number of procedures performed per year, the LLDN technique seems to be as safe as OLDN, providing a similar early post-transplant renal function and showing significative difference in the incidence of DGF. The slight difference in the number of acute tubular necrosis between the groups, demonstrated by 99mTc-MAG3 renography, could be due to the low number of patients and should be further investigated