Laparoscopic nephrectomy : analysis of 34 patients 1

Objective: To analyze the clinical experience of laparoscopic nephrectomy for benign and malignant diseases at a university hospital. Methods: From February 2000 to March 2003, 34 patients (14 men and 20 women) underwent transperitoneal laparoscopic total nephrectomy at the Hospital das Clinicas – FMRP-USP: 28 (82.3%) patients had benign diseases and 6 (17.7%) malignant neoplasias. Benign diseases were represented by: urinary stones (N-9, 32.1%), chronic pyelonephritis (N-8, 28.6%), vesicoureteral reflux (N-4, 14.3%), ureteropelvic obstruction (N-3, 10.7%), multicystic kidney (N-2, 7.1%) and pyonephrosis (N-2, 7.1%). Patients age range was 2-79 years (mean – 35,1 years). Results: In 32/34 patients the procedures were accomplished successfully. In 2 (5.8%) cases of pyonephrosis, open conversion was necessary due to perinephric abscess and difficulties in dissection of renal hilum. Two patients had intraoperative complications (1 duodenum serous laceration an 1 vascular lesion of renal hilum), but both were managed laparoscopically. Two (5.8%) post operative complications (1 delayed bleeding and 1 pancreatic fistula) required open surgical exploration. The mean time of hospital stay was 58h (18 to 240h). Conclusion: Laparoscopic nephrectomy proved to be a method safe and associated with a low rate of morbidity, shorter hospital stay and no casualties.


INTRODUCTION
Since the report of the first laparoscopic nephrectomy by Clayman in 1990 1 , the method deserved widespread investigation and use.The advances in technology of instrumentation as well as the establishment of surgical training programs led to execution of more complex procedures in a shorter surgical time.
Despite the fact of the difficulties to perform nephrectomy in cases of pyonephrosis and severe pyelonephritis the technique is considered safe for the treatment of benign and malignant diseases of the kidney 2,3,4,5 .Laparoscopic nephrectomy allows better esthetic results, lower morbidity, lesser postoperative pain, shorter hospital stay and faster return to normal activities than open surgery 6,7 .A longer learning curve and a higher cost of equipment that represent an apparent disadvantage of laparoscopic surgery is counterbalanced by the aforementioned advantages which compares favorably to open surgery 8 .
The aim of this study is to analyze the results of the first 34 laparoscopic consecutive nephrectomies carried out at our institution.
Patients were operated on under general anesthesia and received 1g of intravenous cefazoline 1h before the beginning of surgery followed by 2 additional doses with intervals of 8h.
Patients were placed on operating table in supine position tilted 45º toward the opposite side of the elected for surgery.A Foley catheter was placed in the bladder for 12-24h.In 32 patients the pneumoperitoneum with CO2 gas was established with a Veress´ needle while in 2 the first port was created through a small open incision (Hasson).During the procedure the pressure of pneumoperitoneum was kept in 12 mmHg by an automatic CO2 gas insufflator (Astus TM ).A four-port technique was preferred in the following locations: mid-clavicular line (level of umbilicus -10mm), anterior axillary's line (2 ports of 10mm each) and posterior axillary's line (1 port -10mm).

RESULTS
Surgeries lasted for 180 to 400 minutes (mean 240 minutes -Table 1).Curiously no difference in operating time was observed between procedures for benign or malignant diseases.Hospital stay varied from 18 to 240h with a mean of 58h.Two patients had a prolonged hospitalization due to complications of concomitant diseases (atrial fibrillation and Diabetes Mellitus, respectively 144h and 240h).
We had two intraoperative complications: 1 injury of duodenal serous (right nephrectomy) and 1 lesion of vascular renal hilum (left nephrectomy).Both were managed properly without necessity of conversion to open surgery (Table 2).

TABLE 1:
Hospital stay and operating time.

Time range Mean
Operating time (min) 180 -400 240 Hospital stay (h) 18 -240 58 Two (5.8%) of 34 patients required conversion to open access in consequence of the presence of perinephric abscesses which did not allow a safe dissection of renal artery and vein.
Postoperative complications occurred in 2 cases: 1 pancreatic fistula and 1 delayed bleeding.These 2 patients required open surgical intervention and recovered completely.
Only the patient that showed delayed postoperative hemorrhage required blood transfusion.

DISCUSSION
The length time of laparoscopic nephrectomy depends on the surgeon specific skill dictated by the learning curve 2 .Our data showed a mean operating time of 240 minutes which is similar to that seen in some reports 2,3 but longer than others that refer lower means as 90 minutes 6 .It is worth while to mention that most procedures of our series were performed by medical residents.Injury of abdominal viscera and bleeding are the most common complications of laparoscopic nephrectomy 2 .The rate of 5.8% of such intercurrences observed in our data is comparable to those published elsewhere 2,4,10 .
Conversion to open surgery was necessary in 5.8% of our patients which is in the upper limit of the rate range reported previously 2,3,10 .New surgical interventions in the postoperative period to manage complications in 5.8% of cases is similar to data reported previously 2,10 .
The mean hospital stay of 58h reflects the low morbidity of the method and is in accordance with the literature 2,3,6,7 .

CONCLUSION
Laparoscopic nephrectomy proved to be a method safe and associated with a low rate of morbidity, shorter hospital stay and no casualties.