Laparoscopic cystostomy in pigs: Technique and comparison with traditional open cystostomy for surgical stress

Cystostomy is a common procedure in veterinary surgery. We describe a technique for laparoscopic cystostomy (LC group; n = 7) in Bama miniature pigs and compare the surgical stress induced by this procedure to open cystostomy (OC group; n = 7). A three-portal approach was used for laparoscopic cystostomy. First, we placed 2 simple interrupted sutures between the ventral body wall and urinary bladder. Then, a purse-string suture was placed in the urinary bladder wall, approximately 1 cm cranially to the two sutures. A stab incision was made at the center of the purse-string suture and a 12-F Foley catheter advanced into the urinary bladder; the suture was then pulled tightly and tied. Again, two interrupted sutures were placed 1 cm cranially to the catheter, between the ventral body wall and the bladder, to establish cystopexy. The extracorporeal portion of the catheter was fixed to the skin by a finger-trap suture. Blood samples were collected to measure the white blood cell count and serum concentrations of cortisol, interleukin-6, and C-reactive protein; follow-up laparoscopy was performed 1 month after the surgery. Laparoscopic cystotomy was successfully performed in all the pigs; the mean operating time was 43 ± 5 min. The levels of the stress markers reflected a lower stress response for LC than OC. Thus, LC appears to be better than OC both in terms of technique and physiological responses elicited, and may be more suitable than OC in the creation of experimental animal models for investigations on urinary diseases and those requiring diversion of urine flow. Minimally invasive surgery, urinary bladder, cortisol, C-reactive protein, interleukin-6 Cystostomy is a common surgical procedure performed in the management of several conditions affecting the urinary system, including urolithiasis (Ewoldt et al. 2006, 2008; Franz et al. 2009; Defarges et al. 2013), urethral injuries (Rakestraw et al. 1995), neurogenic bladder atony (Boothe 2000), and transitional cell carcinoma (Henry et al. 2003; Smith et al. 1995). In experimental animal models, cystostomy is performed to measure the urine output, generally via celiotomy (London et al. 2000; Nieuwoudt et al. 2006; Arkadopoulos et al. 2011; Nastos et al. 2011). Minimally invasive surgery is known to be associated with early recovery and less pain compared to open surgery (Boothe 2000; Ewoldt et al. 2006; Mathon et al. 2009; Lansdowne et al. 2012; Azzouni et al. 2013). Studies have shown that the serum concentrations of interleukin-6 (IL-6) and C-reactive protein (CRP) are lower for laparoscopic procedures than for open surgeries (Cho et al. 1994; Halevy et al. 1995; Maruszynski and Pojda 1995; Karayiannakis et al. 1997; Hildebrandt et al. 2003). On the other hand, some studies have shown no significant differences between the two surgical approaches in the surgical stress response, which is measured in terms of cortisol (COR) concentrations (Jakeways et al. 1994; Targarona et al. 1996; Sagaon et al. 2000). In this study, we introduce a laparoscopic technique for performing percutaneous tube cystostomy in healthy male pigs. Additionally, we sought to compare the surgical stress induced by the laparascopic and open surgical approaches for cystostomy and determine whether minimally invasive bladder surgery is beneficial for the animal models used in investigations of conditions affecting the urinary system. ACTA VET. BRNO 2014, 83: 385–391; doi:10.2754/avb201483040385 Address for correspondence: Hong-bin Wang College of Veterinary Medicine Northeast Agricultural University No. 59 Mucai Street, Harbin 150030, China Phone: +86 187 450 514 29 E-mail: [email protected] http://actavet.vfu.cz/ Materials and Methods Animals Fourteen healthy male Bama miniature pigs were the subjects of these studies. The mean age of these pigs was 4 (range 3–6) months and weight was 21.4 (range 15.5–25.8) kg at the start of the study. They were randomly divided into two groups: one underwent laparoscopic cystostomy (LC group; n = 7) and the other underwent open surgical cystostomy (OC group; n = 7). The pigs were housed individually and fed a standard piglet diet and tap water ad libitum. Care and handling of the animals were in accordance with regulations for the administration of affairs concerning experimental animals (Approved by the State Council on October 31, 1988 and promulgated by Decree No. 2 of the State Science and Technology Commission on November 14, 1988). Approval of the experimental protocol was obtained from the Northeast Agricultural University Ethics Committee. Anaesthetic protocol Food and water were withheld for 12 and 6 h before the surgery to minimize the risk of damage to the viscera during the placement of the cannula. Anaesthesia for each procedure consisted of a mixture of tiletamine/ zolazepam (3.0 mg/kg; Zoletil® 100; Virbac Corporation, Carros, France), xylazine (1.2 mg/kg; Rompun®, Bayer, Germany), and tramadol (1.6 mg/kg; Tramal® 100; Grunenthal GmbH, Germany) intramuscularly (Lu et al. 2010). The animal was intubated with a 6.0-mm tracheal tube and mask ventilation with 100% oxygen. Physiological indicators including the heart rate, arterial blood pressure, arterial haemoglobin oxygen saturation, respiratory rate, and rectal temperature were measured continuously with a non-invasive monitor (Philips IntelliVue MP30; Philips Medizin Systeme Boeblingen GmbH, Germany). Body temperature was maintained between 36 °C and 38 °C by warming the operating table and using an infrared heating lamp. Throughout the procedure, saline (0.9% NaCl) was continuously infused at a rate of 3 ml/kg/h via the marginal ear vein of the pig, and vital signs were continuously monitored with a Philips IntelliVue MP30 monitor.