The effect of ketamine infusions on the minimum alveolar concentration of isoflurane in cats

Effect of transdermally administered fentanyl on the minimum alveolar concentration of isoflurane in cats

“…The cardiovascular, blood gas, acid-base, and temperature variables measured at isoflurane MAC are similar to those reported previously (Steffey & Howland 1977), although the heart rate of 169 ± 32 beats minute )1 is higher, but closer to that reported by us previously ). In the study reported here, packed cell volumes are lower than those reported in other studies (Steffey & Howland 1977;Ilkiw et al 1997) possibly due to blood sampling. In the previously mentioned studies, blood was only sampled during the study time whereas in this study blood sampling for plasma fentanyl determinations was carried out before, as well as, during the study.…”

Isoflurane MAC determination in dogs using three intensities of constant-current electrical stimulation

“…Regardless, the same definition of positive response was applied to all MAC determinations and was very unlikely to affect the main results and conclusions of the present study. In the present authors' opinion, the most likely cause of the higher MAC TAILCLAMP found in this study is a population-based variation in inhalant anesthetic response, which has been previously demonstrated in mice and cats (Koblin et al 1980;Ilkiw et al 1997;Escobar et al 2012). Isoflurane MACs in cats have been reported at 1.28-2.07% when using the tail clamp as the noxious stimulus, even when determined by the same research groups (Ilkiw et al 1997;Escobar et al 2012).…”

“…In the present authors' opinion, the most likely cause of the higher MAC TAILCLAMP found in this study is a population-based variation in inhalant anesthetic response, which has been previously demonstrated in mice and cats (Koblin et al 1980;Ilkiw et al 1997;Escobar et al 2012). Isoflurane MACs in cats have been reported at 1.28-2.07% when using the tail clamp as the noxious stimulus, even when determined by the same research groups (Ilkiw et al 1997;Escobar et al 2012). Other potential causes of increased MAC TAILCLAMP , such as a true increase in MAC or an overestimation of arterial partial pressure of isoflurane from the FE 0 Iso measurements, were excluded in the present study.…”

Effects of remifentanil on measures of anesthetic immobility and analgesia in cats

“…25 However, even with other µor κ-agonists (or a combination of µand κ-agonists), reduction of isoflurane MAC in cats is a maximum of 11% to 35%. 26,27 These modest effects are typically achieved only with high doses of opioids and may reflect activity at nonopioid receptors. It is possible that differences in remifentanil activity at nonopioid targets in cats account for the lack of effects on isoflurane MAC in the study reported here.…”