Journal of Veterinary Anaesthesia最新文献

The post operative analgesic and sedative effects of flunixin (1 mgkg bwt) iv were investigated for the first 90 min post surgery in 20 cats undergoing a variety of surgical procedures. The results were compared with those obtained in another 20 cats, subjected to similar anaesthetic and surgical procedures, but treated with pethidine, 3 mgkg bwt iv. Post operatively, the analgesic effect of flunixin was shown to be adequate and its administration safe, so that it may reasonably be included among possible post operative analgesic treatments of choice in cats.

The minimum alveolar concentration (MAC) of desflurane was measured in 6 ponies (aged 1 or 2 years) following induction of anaesthesia with iv xylazine (1.1 mgkg bwt) followed by ketamine (2.2 mgkg bwt). The stimulus utilised was electrical; pulses of 50 volts, 10 dsec duration delivered at 5 Hz, applied for 60 s across needles inserted 1 cm apart into the buccal mucosa (n = 2) and/or the coronary band (n = 6). Stimulation was not commenced until at least 1 h following anaesthetic induction, and the time of the final MAC measurement ranged from 2.5–3.5 h. The mean (± sd) MAC of desflurane under these circumstances was 7.0% (± 0.85) with a range from 5.8%-8.3%. One pony behaved aberrantly following a positive response to the stimulus and the MAC measurement was repeated 10 weeks later.

At the end of the anaesthetic period xylazine (0.2 mgkg bwt) was administered iv. Mean time to standing was 13.3 (± 2.9) min, range 9–17 min, and the quality of recovery was excellent.

This study assessed the effect of pre-operative starvation on intramperative arteriaI oxygen tension (PaO₂) by examination of anaesthetic records from starved and non-starved horses undergoing general anaesthesia. PaO₂ data from 69 horses were included, 33 of which were starved pre-operatively and 36 were not. Thirty minutes after induction of anaesthesia the mean PaO₂ in the non-starved group was higher than in the starved group (non-starved 40 [2649] kPa vs starved 30 [15–46] kPa. median and 25–75 percentile) but at 60 and 90 min the values for PaO₂ for the non-starvcd group were lower than those for the starved group (60 min: starved 31 [15–49] kPa vs non-starved 27 [11–38] kPa; 90 min: starved 31 [1244] kPa vs non-starved 22 [12–38] kPa) None of the differences between these values was statistically significant. Pre-operative starvation did not significantly increase intra-operativc PaO₂ under the conditions of this study.

Lactic acid was infused iv in 6 Welsh ponies during pentobarbitone anaesthesia to investigate whether lactate triggers the pituitary-adrenal response to anaesthesia. Ponies were premedicated with acepromazine and anaesthesia was induced with pentobarbitone iv and maintained with pentobarbitone/oxygen for 2 h. Immediately after induction, 3% L(+) lactic acid infusion was started and adjusted to maintain plasma lactate concentration between 2 and 2.5 mmol/l. Cardiorespiratory function, temperature. PCV, plasma glucose, lactate, βendorphin, ACTH, cortisol and catecholamine concentrations were measured before, during and after anaesthesia. Hypothermia, reduced PCV, slight hypotension (minimum value 84 ± 6 mmHg 20 min after induction of anaesthesia), hyperoxia and marked bradypnoea developed during anaesthesia. No acidaemia occurred. Plasma glucose concentration increased at the end of anaesthesia. There were no changes in plasma ACTH, cortisol and catecholamine concentrations, but plasma & endorphin increased after induction until the end of anaesthesia. There was a correlation between plasma lactate and β-endorphin concentrations (P<0.001, r=0.63), which may suggest that lactate stimulates βendorphin release. Beta-endorphin was apparently secreted independently from ACTH and appears to be a sensitive marker of a stress response.