Tierärztliche Hochschule Hannover Vergleichende Studie zur

Publikation 2
whether movement by the animals in Group EPI represent a reaction to an aversive
sensation caused by surgical intervention or if they are an expression of discomfort
being restrained in an unfamiliar proprioceptive state. In an attempt to prevent
misinterpretation of the VAS, we recorded specific reactions only to pre-defined intraoperative
procedures which are commonly regarded as painful (e.g. the incision of
the skin or sutures of muscular tissue).
As expected the INH anaesthesia was rapidly adjustable and an adequate depth of
anaesthesia was easy to maintain, which is supported by the low VAS. By inference,
intra-operative agitations reflect an unpleasant and aversive sensory experience
(pain) suffered by the calf (Anil et al. 2002). According to the VAS, the EPI
anaesthesia did not alleviate intraoperative pain as much as INH anaesthesia, but
provided superior analgesia compared to the INJ anaesthesia. However, low VAS
scores alone are insufficient to indicate low pain sensation, as immobility in inhalation
anaesthesia is due to depression of spinal alpha-motor neurons and not due to
analgesia alone.
Cortisol levels increased in response to the surgical procedure in all three groups,
indicating that neither inhalation anaesthesia, nor injection anaesthesia or epidural
anaesthesia were able to prevent the surgical stress response. A total suppression of
the endocrine stress response is unachievable, because general anaesthesia has
little effect on the direct release of cytokines into the bloodstream (acute phase
response) after local trauma and injury (Imura et al. 1991; Desborough 2000).
Increased cortisol levels are not a specific indicator for pain, as they are also
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