A dog model to study ovary, ovarian ligament and visceral pain
Article first published online: 14 APR 2011
© 2011 The Authors. Veterinary Anaesthesia and Analgesia © 2011 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists
Veterinary Anaesthesia and Analgesia
Volume 38, Issue 3, pages 260–266, May 2011
How to Cite
Boscan, P., Monnet, E., Mama, K., Twedt, D. C., Congdon, J., Eickhoff, J. C. and Steffey, E. P. (2011), A dog model to study ovary, ovarian ligament and visceral pain. Veterinary Anaesthesia and Analgesia, 38: 260–266. doi: 10.1111/j.1467-2995.2011.00611.x
- Issue published online: 14 APR 2011
- Article first published online: 14 APR 2011
- Received 11 January 2010; accepted 19 June 2010.
- reproductive tract;
- visceral pain
Objective A dog model was developed to study visceral pain by stimulating the ovarian ligament.
Study design Prospective experimental trial.
Animals Twelve 1-year old female hound dogs weighing 25.7 ± 3.6 kg.
Methods Dogs were anesthetized with sevoflurane. The right ovary was accessed via laparoscopy. A suture was placed around the ovarian ligament and exteriorized through the abdominal wall for stimulation. The noxious stimulus consisted of pulling the ovary and ovarian ligament with a force transducer. The response to noxious stimulation was determined using the anesthetic minimum alveolar concentration requirement (MAC) for sevoflurane. The ovarian MAC was compared to the standardized somatic noxious stimulation tail clamp MAC. The results are depicted as mean ± SD and corrected to sea-level.
Results The stimulus–response curve during ovarian stimulation in three dogs was hyperbolic and best represented by a three-parameter logistic growth curve model. The curve plateaued at 7.12 ± 4.19 N. From the stimulus-response curve, we chose 6.61 N to test the consistency and repeatability of the model in nine dogs. The ovarian stimulation MAC for sevoflurane in these dogs was 2.16 ± 0.46%. The ovarian stimulation confidence interval and limits are comparable to the results from tail stimulation MAC. The tail stimulation MACs before and after laparoscopy surgery were not different (1.86 ± 0.28% and 1.77 ± 0.38% respectively; p > 0.05) but lower when compared to the ovarian MAC (p < 0.01). The dogs recovered from anesthesia without complications.
Conclusions and clinical relevance The ovarian stimulation model is an adequate and repeatable means of producing visceral stimulation to determine MAC. The model may provide a humane mechanism to study the effectiveness of analgesics for acute ovarian pain.