Laparoscopic renal cryoablation: impact on renal function and blood pressure.

OBJECTIVES: To evaluate the renal function and blood pressure outcomes after laparoscopic renal cryotherapy. Laparoscopic renal cryoablation is a developmental minimally invasive modality for the treatment of renal neoplasms. After cryotherapy, a segment of renal parenchyma is rendered ischemic/necrotic and left in situ. It is currently unknown whether this may trigger renin overproduction and thus renin-mediated hypertension. METHODS: Data are presented for 22 of 56 treated patients, each of whom completed a minimum follow-up of 6 months. The data were obtained from patient charts, phone interviews, and/or questionnaires. These results were statistically compared over time by paired t tests. RESULTS: The mean follow-up was 20.6 months. No significant differences were found between the preoperative and most recent postoperative serum creatinine (sCr) levels (1.13 and 0.91 mg/dL, respectively), systolic and diastolic blood pressure values (135.6 versus 131.2 mm Hg and 78 versus 72.7 mm Hg, respectively), or in the estimated creatinine clearance (P <0.05). The number or dose of antihypertensive medications did not change during the follow-up period for any patient. In 3 patients with a solitary kidney, the blood pressure and sCr values remained unchanged (mean preoperative sCr 1.43 mg/dL and mean postoperative sCr after a minimum of 6 months 1.33 mg/dL). CONCLUSIONS: Laparoscopic renal cryoablation did not have a deleterious impact on renal function or blood pressure during a mean follow-up of 20.6 months.

Laparoscopic orthotopic ileal neobladder.

BACKGROUND AND PURPOSE: Orthotopic ileal neobladder is currently the preferred continent urinary diversion in suitable patients undergoing radical cystectomy for muscle-invasive bladder cancer. To our knowledge, presented herein is the initial report of laparoscopic orthotopic ileal neobladder following cystectomy that was performed completely intracorporeally in a porcine model. MATERIALS AND METHODS: The laparoscopic technique was developed in seven pigs. Subsequently, a long-term survival study was performed in 12 consecutive animals. Laparoscopic cystectomy was performed, preserving the urethral sphincter. An ileal segment of 35 cm (first three animals), 45 cm (next four), or 55 cm (final five animals) with adequate mesentery was isolated; and ileal continuity was restored intracorporeally by a stapled anastomosis. Ileal detubularization for construction of an ileal neobladder, urethroileal anastomosis, and bilateral stented ileoureteral anastomoses to a tubular Studer limb extension were all created completely intracorporeally using only laparoscopic free-hand suturing and knot-tying. Biochemical data (preoperative and serial postoperative hemoglobin, renal panel, blood gases), radiologic studies (intravenous urogram, retrograde pouchgram), functional measures (neobladder urodynamics, Whitaker pressure-flow study of both ureters), and microscopic evaluation of the neobladder and ureteroileal and urethroileal anastomotic sites were obtained to evaluate the long-term functional and anatomic outcome. RESULTS: Completely intracorporeal laparoscopic construction of an ileal orthotopic neobladder was successful in all 12 animals without intraoperative or early postoperative complications or open conversion. The mean operating time was 5.4 hours (range 4.5-6.5 hours), and the blood loss was minimal. All study pigs survived their predetermined follow-up period, ranging from 1 to 3 months. Late complications occurred in three animals: one port-site abscess and two cases of E. coli pyelonephritis and azotemia, leading to one death at 2 months. The mean serum creatinine concentrations were 1.33 mg/dL, 1.61 mg/dL, and 1.55 mg/dL at 1, 2, and 3 months, respectively. The mean neobladder capacity was 420 mL (range 250-700 mL) with pressures < or = 20 cm H2O (range 17-20 cm H2O). Pre-euthanasia Whitaker testing confirmed excellent drainage in all 24 ureters. No ileoureteral or ileourethral anastomotic strictures or leaks were noted on intravenous urography, retrograde pouchgram, or postmortem physical calibration of the anastomotic sites. Histologic examination confirmed excellent healing without obvious fibrosis. CONCLUSION: Laparoscopic construction of an orthotopic neobladder is feasible. The anatomic and functional outcome is excellent and comparable to that of open surgery. Clinical application is imminent.

Retroperitoneal minilaparoscopic nephrectomy in the rat model.

OBJECTIVES: Development of small animal models for laparoscopic surgery is important for basic pathophysiologic and oncologic studies, instrument development, and surgical training. Although transperitoneal laparoscopy has been described in the rat, the technical feasibility of the retroperitoneoscopic approach for major renal surgery has not been reported previously. Herein, we describe the development of a rat model for retroperitoneal minilaparoscopic nephrectomy. METHODS: Sixteen male Sprague-Dawley rats underwent a three-port bilateral retroperitoneoscopic nephrectomy using 2 and 3-mm instruments and optics exclusively. After developing the technique in 10 animals, the study was conducted in 6 animals. Following retroperitoneal balloon dilation and CO(2) pneumoretroperitoneum (mean 4.5 mm Hg), nephrectomy was accomplished by intracorporeal en bloc ligation of the renal pedicle. To prevent peritoneal entry, the anterior surface of the kidney was mobilized subcapsularly. Volume of the created retroperitoneal space and peritoneal integrity were confirmed by a contrast x-ray study. Intraperitoneal pressure was monitored constantly during the procedure. RESULTS: Mean surgical time was 74.5 minutes (range 60 to 95) and estimated blood loss was less than 1 mL. Mean volume of the retroperitoneal space was 8.4 mL after initial balloon dilation, and 11.5 mL after nephrectomy. Mean weight of the excised kidneys was 1. 4 g. Inadvertent peritoneotomy occurred during 3 of 12 study nephrectomies. Complications included renal artery hemorrhage leading to death in 1 animal and renal vein injury in 1 animal. CONCLUSIONS: Laparoscopic retroperitoneal nephrectomy in the rat model is technically feasible. This novel small animal model can be used for further studies of the retroperitoneal laparoscopic approach.

A study of the association between epistaxis and the severity of hypertension.

Hypertension (HTN) has frequently been cited as a general risk factor for epistaxis. However, studies dealing with this association have yielded equivocal results. In this study, a sample of 121 hypertensives (blood pressure > or = 140/90 mmHg) was selected to evaluate the association between the severity of HTN and a previous history of epistaxis. Patients with an average blood pressure > or = 160/100 mmHg were classified as suffering from a more severe form of HTN and were compared with those with a less severe form of the disease (160/100 mm Hg < or = blood pressure > or = 140/90 mm Hg). The frequency of epistaxis did not differ among patients categorized by the severity of HTN. Users of aspirin were found to be twice as likely to have a history of epistaxis. In addition, there was a statistical tendency for an association between a history of epistaxis and the duration of hypertension. We conclude that the severity of HTN and a history of epistaxis were not associated in a cohort of hypertensive patients. The identification of other risk factors for epistaxis, including the duration of HTN, deserves further study.