Laparoscopic live donor nephrectomy: pre-operative assessment of technical difficulty1

Laparoscopic live donor nephrectomy decreases disincentives to live kidney donation. Thus, many centers are interested in adopting this procedure. However, the high stakes involved for both the donor and the recipient, and the technical difficulties of the operation, have tempered the enthusiasm of some surgeons. Ideally, if early in their series, surgeons could select patients that would be the least challenging technically, it would facilitate the dissemination of this operation. The purpose of this study is to determine if anatomic or radiologic parameters can accurately assess pre-operatively the degree of technical difficulty of laparoscopic live donor nephrectomy for any individual patient. Abdominal spiral three-dimensional CT scanning was performed prior to laparoscopic donor nephrectomy. CT scans were reviewed for six radiographic anatomic parameters. Seven clinical anatomic measurements relating to body habitus were recorded upon induction anesthesia at the time of surgery. Demographic data for gender, age, race, weight, height, and smoking history were collected. Following laparoscopic live donor nephrectomy, the following six component parts of the operation were graded on a scale of 1-4 (1 = easy, 4 = very difficult) for technical difficulty: a) mobilization of the colon; b) mobilization of the upper pole; c) dissection of the renal vein; d) dissection of the renal artery; e) division of the adrenal vein; and f) dissection of the ureter. Also, operative time, estimated blood loss, and intra-operative fluid requirements were recorded as surrogate markers of operative difficulty. Forty-one patients were included in the study. Laparoscopic donor nephrectomy was successfully completed in all cases. The sum of the difficulty scores was 9.9 ± 3.1 (mean) (range, 6-18). No anatomic, demographic, or radiologic parameters were predictive of the total operative difficulty score. Of the surrogate markers, only operative time correlated with total difficulty score (R = 0.47, p = 0.003). Donor weight and abdominal girth correlated with operative time (R = 0.50, p = 0.002; R = 0.38, p = 0.019) but not with total difficulty score (R = 0.10, p = 0.51; R = -0.02, p = 0.90, respectively). When the easiest cases and the hardest cases (≤25th percentile and > 75th percentile total difficulty score, respectively) were segregated out, again no anatomic, demographic, or radiologic parameters were predictive of operative technical difficulty. In conclusion, laparoscopic live donor nephrectomy technical difficulty could not be predicted by body habitus from the variables examined in this study. Hence, it was equally likely that performing laparoscopic live donor nephrectomy using a heavy donor would be technically easy, as using a thin donor would be difficult. Although, in general, operative time increased with donor size and weight, it appears that laparoscopic live donor nephrectomy operative technical difficulty is dependent upon such factors as amount of laparoscopic working space, quality of tissue planes, and retractability of the colon and mesocolon; factors that, to date, are not quantifiable.