Thomas H.S. Hsu

LAPAROSCOPIC RENAL AND ADRENAL SURGERY IN OBESE PATIENTS: COMPARISON TO OPEN SURGERY

PURPOSE The efficacy and morbidity of laparoscopic renal and adrenal surgery in comparison to open surgery in obese patients are unknown. This retrospective study was performed to compare the outcome of laparoscopic versus open renal and adrenal surgery in the markedly and morbidly obese patient (body mass index 30 or greater). MATERIALS AND METHODS The study group comprised all obese patients undergoing laparoscopic renal and adrenal surgery (laparoscopic group) from August 1997 to February 1998 at our institution. The majority of procedures were performed using a retroperitoneoscopic approach via the flank. These patients were compared with all obese patients undergoing open renal and adrenal surgery (open group) from 1994 to 1998. Open group patients with factors precluding laparoscopic surgery were excluded from the study (mass greater than 10 cm., renal vein and/or inferior vena caval thrombus and extension outside Gerotas fascia). RESULTS There were 21 obese patients in each group and baseline parameters were comparable between groups. Median body mass index in the laparoscopic and open groups was 34 and 31, respectively. Median surgical time between the laparoscopic (210 minutes) and open (185) groups was comparable (p = 0.16). However, the laparoscopic group had decreased blood loss (100 versus 350 ml., p<0.001), quicker resumption of oral intake and ambulation (less than 1 versus 5 days, p<0.001), decreased narcotic analgesic requirements (12 versus 279 mg., p<0.001), shorter median hospital stay (less than 1 versus 5 days, p<0.001) and quicker convalescence (3 versus 9 weeks, p<0.001). There were 6 complications in 4 laparoscopic cases and 14 in 9 open surgery cases (p = 0.16). CONCLUSIONS Markedly obese patients have an increased risk of complications from surgery, regardless of the approach. Our data suggest that laparoscopic renal and adrenal surgery is technically feasible in the markedly and morbidly obese patient, and compared with open surgery results in significantly decreased blood loss, quicker return of bowel function, less analgesic requirement, shorter convalescence and reduced hospital stay.

Robotic-assisted laparoscopic pyeloplasty : A pilot study

OBJECTIVES Robotic technology has been employed to manipulate the laparoscope during urologic procedures. However, to our knowledge, robotic technology has not been previously applied to actually perform the urologic laparoscopic procedure. The objective of this study was to determine the feasibility and efficacy of performing robotic-assisted laparoscopic pyeloplasty and compare it with conventional laparoscopic pyeloplasty in an acute porcine model. METHODS Five female swine (10 kidneys) were prospectively randomized to undergo unstented robotic-assisted laparoscopic pyeloplasty (6 kidneys) or conventional laparoscopic pyeloplasty (4 kidneys). Robotic pyeloplasty was performed with the Zeus robotic system, which incorporates three remote-controlled interactive arms: one voice-activated arm to control the laparoscope and two robotic arms to manipulate purpose-designed instruments. Tissue dissection and transection of ureteropelvic junction area were performed manually by conventional laparoscopy. The pyeloureteric anastomosis during the robotic-assisted pyeloplasty was performed completely robotically from a remote workstation using running 5-0 absorbable sutures. Conventional laparoscopic pyeloplasty was performed manually by laparoscopic intracorporeal suturing and knot-tying techniques. Immediate patency and anastomotic integrity were evaluated by intravenous indigo carmine and ex vivo retrograde ureteropyelogram. RESULTS In comparing robotic and conventional laparoscopic pyeloplasty, the following data were obtained: total surgical time (115.2 versus 94.5 minutes, P = 0.2), anastomosis time (75.7 versus 64.3 minutes, P = 0.3), and total number of suture-bites per ureter (13.0 versus 12.5, P = 0.8). Anastomoses were immediately watertight in 5 of 6 robotic and 3 of 4 conventional pyeloplasties. CONCLUSIONS Robotic-assisted laparoscopic pyeloplasty is a feasible and effective procedure that may enhance surgical dexterity and precision. This has implications for clinical applications of laparoscopic telesurgery in the future.

Radiofrequency ablation of the kidney: acute and chronic histology in porcine model

OBJECTIVES To our knowledge, the chronic histopathologic effects of radiofrequency ablation (RFA) of renal parenchyma have not been extensively documented. In this study, we report the light and electron microscopic features of renal RFA in acute and chronic porcine models. METHODS Eleven animals underwent renal RFA of the lower pole kidney bilaterally. RFA was performed laparoscopically in 6 acute animals and percutaneously in 5 chronic animals. Acute animals were killed immediately following surgery. One chronic animal each was killed on postoperative day 3, 7, 14, 30, and 90. Histopathologic evaluation of all renal tissue specimens was carried out with light and electron microscopy. RESULTS Acutely, the renal radiolesion appeared as a yellowish white, well-circumscribed, necrotic area on gross examination, with evidence of extensive coagulative necrosis and marked inflammation on microscopic examination. From day 1 through 90, light and electron microscopy revealed evidence of progressive, irreversible cell death and necrosis with diminishing inflammatory response in the glomeruli, tubules, and renal interstitium. RFA lesions underwent gradual spontaneous resorption of the necrotic area with ultimate autoamputation. CONCLUSIONS RFA results in necrosis of the ablated renal parenchyma.

ROBOTIC REMOTE LAPAROSCOPIC NEPHRECTOMY AND ADRENALECTOMY: : THE INITIAL EXPERIENCE

PURPOSE We evaluated the feasibility of performing laparoscopic nephrectomy and adrenalectomy exclusively by using robotic telepresent technology from a remote workstation and compared outcomes with those of conventional laparoscopy in an acute porcine model. MATERIALS AND METHODS Five pigs underwent bilateral laparoscopic nephrectomy (robotic in 5 and conventional in 4) and adrenalectomy (robotic in 4 and conventional in 3). In the 9 robotic laparoscopic procedures all intraoperative manipulations were completely performed telerobotically from a remote workstation without any conventional laparoscopic assistance on site. Animals were sacrificed acutely. RESULTS Robotic laparoscopic nephrectomy required significantly longer total operative (85.2 versus 38.5 minutes, p = 0.0009) and actual surgical (73.4 versus 27.5 minutes, p = 0.0002) time than conventional laparoscopy. However, blood loss and adequacy of surgical dissection were comparable in the 2 groups. Robotic laparoscopic adrenalectomy required longer total operative (51 versus 32.3 minutes, p = 0.13) and actual surgical (38.5 versus 18.7 minutes, p = 0.14) time than conventional laparoscopy. The solitary complication in this study was an inferior vena caval tear during robotic right adrenalectomy, which was adequately repaired by sutures telerobotically in a remote manner. CONCLUSIONS To our knowledge we present the initial experience with remote telerobotic laparoscopic nephrectomy and adrenalectomy. Telepresent laparoscopic surgery is feasible.

Radical nephrectomy and nephroureterectomy in the octogenarian and nonagenarian: comparison of laparoscopic and open approaches

OBJECTIVES To retrospectively compare the outcome of laparoscopic and open radical nephrectomy or nephroureterectomy in patients 80 years old or older, inasmuch as the tolerance profile of major laparoscopic renal surgery in comparison to open surgery in the elderly patient has not been previously reported. METHODS Since September 1997, 11 patients 80 years old or older underwent retroperitoneal laparoscopic radical nephrectomy or nephroureterectomy for cancer. These patients were compared with 6 consecutive patients 80 years old or older who underwent comparable open surgery at our institution since January 1994. No tumor had computed tomographic evidence of lymphatic, vascular, or perirenal extension. RESULTS Baseline parameters were comparable between the laparoscopic and open groups. The laparoscopic group had a similar median surgical time (210 minutes versus 175 minutes; P = 0.1) and blood loss (150 mL versus 125 mL; P = 0.8) compared with the open group. However, specimen weight was larger in the laparoscopic group (568 g versus 292 g; P = 0.04). Moreover, the laparoscopic group had a quicker resumption of oral intake (less than 1 day versus 4 days; P <0.001), decreased narcotic requirements (14 mg versus 326 mg; P = 0.004), shorter hospital stay (2 days versus 6 days; P <0.001), and faster convalescence (14 days versus 42 days; P <0.001) compared with the open group. CONCLUSIONS Retroperitoneal laparoscopic radical nephrectomy and nephroureterectomy are well tolerated by the elderly patient. Although our sample size was small, it appears that laparoscopy is an excellent alternative to open surgery for excision of selected renal malignancies in the octogenarian and nonagenarian population.

LAPAROSCOPIC REPAIR OF RENAL ARTERY ANEURYSM

PURPOSE We describe technical considerations of the laparoscopic repair of a renal artery aneurysm. MATERIALS AND METHODS A 57-year-old woman presented with a 3 cm. aneurysm of the distal left main renal artery at its bifurcation. Using a purely laparoscopic 4-port transperitoneal technique the aneurysm was completely mobilized from its location behind the renal vein. Its 3 feeding vessels were controlled individually with bulldog clamps. The aneurysm sac was bivalved and precisely trimmed to conform with the diameter of the main renal artery. Vascular reconstruction was performed with running freehand laparoscopic suturing and intracorporeal knot tying using 4-zero polypropylene suture. RESULTS Warm ischemia time was 31 minutes, total operative time was 4.2 hours, blood loss was 100 cc and hospital stay was 2 days. Postoperatively renal scan showed improved perfusion and renal arteriography confirmed adequate repair of the aneurysm. CONCLUSIONS Laparoscopic repair of the renal artery aneurysm is feasible. To our knowledge we present the initial clinical report of laparoscopic renovascular surgery in the literature.

THE SUPINE STRESS TEST: A SIMPLE METHOD TO DETECT INTRINSIC URETHRAL SPHINCTER DYSFUNCTION

PURPOSE A new clinical test for intrinsic urethral sphincter dysfunction is proposed and compared to abdominal leak point pressure determination by video urodynamics. MATERIALS AND METHODS Patients were prospectively included in the study if they had stress urinary incontinence symptoms and were to undergo video urodynamic testing. Patients with urinary tract infection, cystocele, rectocele and vaginal vault prolapse were excluded from study. A supine stress test using cough and Valsalvas maneuvers was performed after bladder filling to 200 ml. with sterile normal saline solution by gravity. Efflux of the bladder solution from the meatus coinciding with the cough or Valsalva maneuver indicated a positive clinical test. A video urodynamic study, including abdominal leak point pressure, was performed. Intrinsic urethral sphincter dysfunction was diagnosed if abdominal leak point pressure was less than 100 cm. water. Test indexes were calculated based on the results of the supine stress test and the abdominal leak point pressure measurements. RESULTS Results were positive in 30 of 41 consecutive patients and negative in 11. Using abdominal leak point pressure measurement, the supine stress test had 93.5% sensitivity, 90.0% specificity, 96.7% positive predictive value and 81.8% negative predictive value for detecting intrinsic urethral sphincter dysfunction. CONCLUSIONS The supine stress test is easy, quick and inexpensive, and a positive test is a reliable predictor of intrinsic urethral sphincter dysfunction. A negative test is highly correlated with the absence of intrinsic urethral sphincter dysfunction during video urodynamic testing. This test is more reliable in diagnosing intrinsic urethral sphincter dysfunction than other nonurodynamic tests reported in the literature. The supine stress test can be a useful supplement to cotton swab testing for urethral hypermobility in determining the appropriate management for stress urinary incontinence.

TECHNIQUES IN ENDOUROLOGY: Retroperitoneoscopic Adrenalectomy: Lateral Approach

Laparoscopy has become the essential surgical approach to the adrenal gland at many institutions, including ours. At the Cleveland Clinic, laparoscopic adrenalectomy for benign and malignant adrenal neoplasms can be performed by either the transperitoneal or the retroperitoneal approach. Herein, we present our technique of lateral retroperitoneal laparoscopic adrenalectomy.

THE EFFECT OF DOPAMINE ON RENAL FUNCTION IN SOLITARY PARTIAL NEPHRECTOMY SURGERY

PURPOSE Dopamine continues to be used for preventing and treating acute renal failure. We determined the effects of dopamine on postoperative renal function in patients with a solitary kidney undergoing partial nephrectomy. MATERIALS AND METHODS We performed a prospective randomized controlled study at a tertiary care referral center involving 24 patients with a solitary kidney undergoing partial nephrectomy secondary to malignancy. Patients were randomized to receive dopamine (11) [corrected] or no dopamine (13) [corrected]. Intraoperatively those assigned to the dopamine group received a 3 microg./kg. per minute dopamine infusion. Patients in each group received an adequate amount of fluid to maintain good urine production, systemic blood pressure and central venous pressure. Serum electrolytes, blood urea nitrogen, creatinine, serum and urine osmolality, and urine output were measured at baseline, intraoperatively and through postoperative day 4. Preoperatively and postoperatively renal blood flow and the glomerular filtration rate were measured. RESULTS In the 2 groups blood urea nitrogen and serum creatinine increased postoperatively. Although the degree of this increase showed a trend to be lower in the dopamine group, the difference did not reach statistical significance. There was no difference in renal blood flow or the glomerular filtration rate in the treatment groups. CONCLUSIONS Administering dopamine to patients with a solitary kidney undergoing partial nephrectomy provided no renoprotective effect.

METABOLIC ABNORMALITIES IN PATIENTS WITH CALICEAL DIVERTICULAR CALCULI

PURPOSE We determined the incidence and spectrum of metabolic abnormalities in patients with caliceal diverticular calculi. MATERIALS AND METHODS Five men and 9 women with caliceal diverticular calculi underwent metabolic evaluation, including determination of serum electrolytes, calcium, phosphate and uric acid, and 24-hour urinary volume, creatinine, calcium, oxalate, uric acid and citrate. RESULTS Of the 14 patients 7 (50%) had urinary excretion abnormalities promoting stone formation, including hypercalciuria in 3, hyperoxaluria in 1, hypercalciuria combined with hyperuricosuria in 1 and hyperoxaluria combined with hyperuricosuria in 2. Two patients had a history of gout while another had radiographic evidence of medullary sponge kidney. Of the patients 9 (64.3%) had a history of synchronous or metachronous calculi distant from the involved caliceal diverticular stone and 5 (55.6%) of these 9 had definable metabolic disorders. However, there was no statistically significant difference in urinary excretion values between patients with or without a history of additional extra diverticular stones. CONCLUSIONS Urinary stasis alone does not explain stone formation in a significant number of patients with caliceal diverticular calculi. Rather, the local physiological environment of the urine likely has a predisposing role and evaluation for metabolic abnormalities should be considered. In some patients cure may be effected by treating the stone and any associated metabolic disorders rather than the diverticulum.