Metamizol and Scopolamine for Conventional or Two-Port Laparoscopic-Assisted Ovariohysterectomy in Dogs

Abstract

Background: Ovariohysterectomy (OVH) is one of the most appliedtechniques in Veterinary Medicine. Although some analgesic protocols are used after this procedure in order to control post operatory pain, there is a lack of knowledge of the efficacy after conventional and two port laparoscopic-assisted techniques in dog female. Although the combined formulation of metamizol and scopolamine is used, there is no knowledge about the efficacy and collateral effects in a 6 h regimen after OVH. The aim of this research was to evaluate the efficacy of metamizol and scopolamine to analgesia after two techniques of OVH in dog female.

Materials, Methods & Results: Fifteen adults and healthy dog female were submitted to OVH, being eight to the conventional procedure and seven to video assisted technic with two ports. The patients received a combination of metamizol and scopolamine, 6-6 h during 48 h and were evaluated before surgery, 60 min after extubation and on 1 h interval during the first 8 h, and at 12, 18, 24, 36, 48 and 72 h after surgery. For this, the University of Melbourne Pain Scale (UMPS) and the short-form of the Glasgow Composite Measure Pain Scale (CMPS-SF) were applied by three evaluators blinded to surgical technic. Glucoses measurement was realized at 1, 6, 12, 24, 48 and 72 h after surgery. Analgesic rescue was not necessary for any animal. Punctuation of UMPS in GC decreases at 8 h and at 5 h, and to GV at 12 and 24 h. Difference between groups happened at 3 h with larger average to GV; at 48 h the punctuation in GC was lager. Considering CMPS-SF to CG, higher average was observed at 1 h and decreased at 2, 3, 8 and 18. At GV highest average points was verified at 1, 2 and 3 h and decreased at 5, 8 and 18 h. Correlation was strong and positive between each two evaluators. Animals of both groups had increased average glucose concentrations from baseline to after surgery and the values reduced to baseline after 24 h; difference between groups were observed at 1 h after surgery, with bigger average to GC. Three animals from the GC had postoperative emesis and one patient vomited after 3 h; other at 6 h and another at 36 and 48 h and owners related no vomiting or changes following hospital discharge. The time to first spontaneous food intake was earlier to GV and time to first defecation was no different between groups. 

Discussion: For the evaluation it was used the UMPS and CMPS-SF since it is know that pain assessment is better performed when multidimensional or composite scales are used. Considering the UMPS, 27 points is considered the most painful condition. In our study it was observed bigger average to GC at 1 h (4,5) and to GV at 2 and 3 h (5,0). According to CMPS-SF, higher punctuation to GC (7.0) was observed than GV (6,0) in a maximum of 24 points. Considering both scales, it could be suggested that the combination of metamizol and scopolamine promote good analgesic effect. The glucoses measurements and the first spontaneous food intake suggested that laparoscopic approaches results in less stress than the traditional procedures, as observed in other studies. Three animals of GC had postoperative emesis, and it signal can be associated to abdominal pain, as well nausea, vomiting, diarrhea and abdominal distention, probably because it is accepted that video surgery promotes less pain and stress than open procedures. The protocol was efficient to control pain after elective conventional and laparoscopic assisted OHV technique in dog female.