Laparoscopic orthotopic gastroileal neobladder and gastroileocystoplasty: technical feasibility and critical analysis of an experimental porcine model / Neobexiga gastroileal ortotópica e gastroileocistoplastia laparoscópicas: viabilidade técnica e análise crítica de um modelo experimental em suínos

Eduardo Franco Carvalhal

Introduction: Composite gastroileal (GI) urinary reservoirs may present advantages over the use of isolated intestinal segments for urinary reconstructive procedures in selected patients. Herein, we present the laparoscopic techniques of gastroileocystoplasty (bladder augmentation) and GI orthotopic neobladder (bladder substitution), performed completely intracorporeally in a porcine model. Technical feasibility and functional results of these procedures are evaluated. Methods: After a pilot study (three animals) to technically standardize the procedures, gastroileocystoplasty (Group I, N = 5) and GI orthotopic neobladder (Group II; N = 10) were performed applying the same principles of wedge gastric resection and ileal resection. In Group II, creation of the neobladder included bilateral ureteral reimplantation into the gastric segment with an anti-reflux technique and an urethro-ileoanastomosis. Staplers and free-hand laparoscopic suture techniques were utilized exclusively, in a completely intracorporeal manner. Preop and postoperative analysis of laboratory data, bladder capacity, image (cystourethrography, intravenous urography) and histological evaluation of the resulting GI reservoirs was concluded at the end of follow-up, at eight and 12 weeks (Group I) and four and eight weeks (Group II). Results: Ileal and gastric patches reached the animal pelvis in all cases. Operative times were 5.2h for Group I and 7.4h for Group II. No conversions or intraoperative deaths occurred. All GI reservoirs were viable by the time of euthanasia in both groups. In Group I, four of the five animals completed the scheduled follow-up of 8 (N = 2) and 12 (N = 2) weeks without complications. One animal received early euthanasia due to pyelonephritis and metabolic alkalosis. Bladder capacity (at a bladder pressure of 20cmH2O) increased from 650ml to 1025ml (p <0.05) after the bladder augmentation procedure. In Group II, five of 10 animals completed the scheduled follow-up at four (N = 3) and eight (N = 2) weeks, with minimal alteration on renal function (pre and postoperative Cr = 1.4 and 2.2mg/dl, respectively; p = 0.09). Three animals had an early euthanasia due to ureteral obstruction and pyelonephritis (N=2) and severe hipochloremic alkalosis (N = 1). Two deaths were associated to bilateral ureteral obstruction and sepsis. Mean bladder capacity for the neobladders was 400ml. No cases of vesico-ureteral reflux were seen at cystourethrography. However, seven of 20 renal units (35%) presented with uretero-gastric stenosis. Bowel obstruction (N = 1), gastric fistula (N = 1) and urinoma (N = 1) were other complications in Group II. Conclusions: Laparoscopic gastric resection for bladder augmentation and substitution purposes is feasible and reproducible. Laparoscopic gastroileocystoplasty presents adequate functional results after three months in the porcine model. Laparoscopic GI neobladder is technically viable in the porcine model, despite its complexity. The initial report is presented. Refinements of laparoscopic anti-reflux ureteral reimplantation techniques are necessary before its clinical application.

AUTOR(ES)

DATA DE PUBLICAÇÃO

RESUMO

ASSUNTO(S)

ACESSO AO ARTIGO

Documentos Relacionados