Assessment of postoperative inflammatory markers and pain in cats after laparoscopy and miniceliotomy ovariectomy

Videosurgery is increasingly used in veterinary medicine. Compared with open surgery, it has been shown to cause minimal pain and promote a more rapid recovery. There are various methods of assessing pain and postoperative inflammation in cats, although their particular behaviours may make these assessments difficult. The aim of this study was to compare levels of postoperative pain and inflammation after laparoscopic ovariectomy with an open minimally invasive technique. Twenty queens were randomly divided into two groups based on the method of haemostasis and surgical technique: (1) laparoscopic ovariectomy using a miniloop (miniloop group (MG)); and (2) minilaparotomy using a Snook hook (control group (CG)). Heart rate (HR), respiratory rate (RR), end tidal CO₂ (EtCO₂) and body temperature were assessed using a multiparametric monitor during anaesthesia and surgery at defined surgical time points (preincision, left ovary manipulation, right ovary manipulation and skin suture). Blood samples (2 mL each) were collected from the jugular vein before surgery and 1, 12, 24, 48 and 72 hours, and 10 days, after endotracheal extubation for blood count analysis and to assess total protein and acute phase proteins (APP). EtCO₂ and RR were significantly higher in MG patients (P<0.001). HR was higher in the CG group for the duration of surgery (P=0.01). Temperature was significantly lower in MG patients (P<0.001). Pain assessment by dynamic interactive visual analogue scale showed no difference between groups or at specific moments of time within groups. Segmented neutrophil counts increased at 24 hours postoperatively and peaked at 48 and 72 hours in MG (P=0.01). The most important result among APPs was haptoglobin, which peaked at 72 hours in MG patients (P=0.001). Patients undergoing minilaparotomy and laparoscopy showed comparable postoperative pain. However, inflammatory changes such as APPs and neutrophil counts were increased in the laparoscopic group.

Repair of Bone Defects with Chitosan-Collagen Biomembrane and Scaffold Containing Calcium Aluminate Cement

Innovative biomaterials can provide a promising new direction for the treatment of bone defects, stimulating a proper repair process, with no damage to adjacent tissues. The purpose of this in vivo study was to evaluate the biocompatibility and the osteoinductive capacity of chitosan-collagen biomembrane and scaffold containing calcium aluminate cement. Eighteen New Zealand white rabbits (Oryctolagus cuniculus) were distributed according to the experimental times of analysis (7, 15 and 30 days). Four bone defects were created in the rabbits calvaria, which were individually filled with the biomembrane, scaffold, blood clot (negative control) and autologous bone (positive control). Histopathological analysis was performed using optical microscope at 32´, 64´, 125´ and 320´ magnifications. Cell response to inflammation and new bone tissue formation was quantified using a score system. The biomembrane group presented greater inflammatory response at 15 days, with significant difference to autologous bone group (p<0.05). There was no statistically significant difference for foreign body type reaction among groups (p>0.05). Concerning new bone formation, linear closure of the defect area was observed more evidently in the group with autologous bone. The scaffold group presented similar results compared with the autologous bone group at 30 days (p>0.05). Both tested biomaterials presented similar biocompatibility compared with the control groups. In addition, the biomembrane and scaffold presented similar osteoinductive capacity, stimulating bone repair process in the course of the experimental time intervals.

Description and Executability of a Novel Pre-tied Mini Ligature (Miniloop) in Laparocopic Ovariectomy in Cats

Background: Ovariectomy(OVE) and ovariohysterectomy (OVH) are the most performed surgical procedures in Veterinary Medicine. In videosurgery, both in stray animals at sterilization campaigns and in the increasing demand of tutors to perform the technique. Laparoscopy results in reduced tissue damage, due to minimal organ manipulation and surgical access hemostasis can be performed by several methods, such as electro-coagulation, clips, and intra and extracorporeal ligatures. A pre-tied ligature system, or endoloop, is a haemostatic technique comprised of a slipknot and knot pusher, which is inserted into the abdominal cavity through one of the laparoscopic ports. The aim of this study was to describe a novel OVE technique in cats, in which haemostasis was performed using miniloop, aimed at reducing the number of ports needed for knot tying.Material, Methods & Results: Ten healthy not spayed female cats, aged 6 months to 5 years, were selected for this study. They were submitted to an OVE using miniloop as haemostasis method. Access to the peritoneal cavity was through two 5 mm ports on the midline of the ventral abdomen, 5 cm apart, with one immediately caudal to the umbilical scar and the other in between the last pair of teats. The first trocar was inserted at the caudal incision using the Hasson technique and a 5 mm zero-degree optics attached to a camera was introduced through it. The placement of the second access port was video assisted. For ovary exposure, the patients were positioned in lateral recumbency on the contralateral side to the ovary being removed. The miniloop was composed of a 2 mm diameter minitrocar, a 1.8 mm knot pusher, and a pre-tied slipknot. It was introduced percutaneously at the lateral abdominal wall. It was inserted attached to a pre-tied loop ligature. A Babcock forceps was used to guide the slipknot until it enveloped the ovarian vessels and the proximal part of the uterine horn. Subsequently, the knot was tightened with the aid of the knot pusher. A second miniligature was applied. The forceps was removed and a Metzenbaum scissors inserted to cut between the ligatures, releasing the ovary with the nylon ligature but keeping the PDS knot. It was performed at both ovary. Mean (±SD) surgical time was 44.8 min (± 13.4) and varied significantly (P = 0.0006) between animals, with the shortest time being 29 min and the longest 66 min. Positioning of the patients in lateral decubitus allowed for good ovarian exposure, without the need for excessive manipulation of the intestinal loops or other abdominal organs. Rupture of the suture thread was the only trans-operative complication observed and occurred in two animals. A second ligature (miniloop) was needed to ensure haemostasis. One cat showed eventration at the site of the caudal port on the second day post-operative.Discussion: The mean surgical time in the present study was lower than reported by some authors, but longer than anothers. Furthermore, the surgical time from this study is similar to that of other studies in cats in which haemostasis of the OAVC was achieved using bipolar electrocoagulation. Surgical team expertise is of outmost importance in minimizing complications and overcoming problems during videosurgical procedures in order to reduce surgical time, such as gas leakage, extensive incision, and difficulty in manipulating surgical instruments.