Comparison of the arterial blood gas, arterial oxyhaemoglobin saturation and end-tidal carbon dioxide tension during sevoflurane or isoflurane anaesthesia in rabbits

Abstract

The effects of sevoflurane or isoflurane on arterial blood gas, arterial oxyhaemoglobin saturation and end-tidal CO2 tension were monitored during induction and maintenance of anaesthesia in 10 premedicated New Zealand White (NZW) rabbits.For induction, the anaesthetic agents were delivered via a face-mask. After induction was completed, an endotracheal tube was introduced for maintenance of anaesthesia for a period of 90 minutes. Changes in heart rate, respiratory rate, arterial blood gas, arterial oxyhaemoglobin saturation, blood pH and end-tidal CO2 tension were recorded. Although sevoflurane and isoflurane produce similar cardiopulmonary effects in premedicated rabbits, sevoflurane provides a smoother and faster induction because of its lower blood/gas partition coefficient. Thus sevoflurane is probably a more suitable agent than isoflurane for mask induction and maintenance. Its lower blood solubility also makes sevoflurane more satisfactory than isoflurane for maintenance of anaesthesia because it allows the anaesthetist to change the depth of anaesthesia more rapidly.

Use of arterial blood gas analysis as a superior method for evaluating respiratory function in pet rabbits (Oryctolagus cuniculus)

“…The values obtained in the present study (mean 33.2) are lower than those previously reported in anaesthetised rabbits but are comparable with those values published for conscious rabbits (Egbrink and others 1989, Flecknell and others 1990, Rich and others 1990, Barzago and others 1992, Sakai and others 1999, Toal and Gul 2006, Allweiler and others 2010). This may be due to hyperventilation, which was noted clinically in all the conscious rabbits in this study; however, no data was collected on respiratory rate.…”

“…This would account for the PaO 2 levels recorded (mean 78.52), compared with the higher values recorded in anaesthetised animals with a FiO 2 of 1, from which mean values of PaO 2 (mm Hg) of 474, 504 (peak) and 455 (trough), 415, 431, 402 and 472 have been reported (Flecknell and others 1990, Pfeiffer and others 2006, Allweiler and others 2010). Many studies using comparable FiO 2 values of 0.25 or 0.21 reported comparable mean PaO 2 values of 102.2, 115 (peak), 100 (trough), 88, 103.5, 67.07 and 72.9, respectively (Egbrink and others 1989, Barzago and others 1992, Sakai and others 1999, Pfeiffer and others 2006, Toal and Gul 2006). A study using a FiO 2 of 0.1 reported a mean value of 35.2 (Sakai and others 1999).…”

Arterial blood gas parameters in pet rabbits anaesthetized using a combination of fentanyl‐fluanisone‐midazolam‐isoflurane

“…The values reported by Allweiler et al . () are closer to physiological arterial gas tension reported in healthy non‐anaesthetized rabbits (Topal & Gul , Schroeder & Smith ) than the values obtained in this study in anaesthetized pet rabbits or that of Topal & Gul (). Differences may originate from type of population (laboratory rabbits versus pet rabbits), variations in the choice of drugs, experimental conditions or individual variations.…”

“…Mean arterial pH in healthy non‐anaesthetized laboratory rabbits has been reported to be 7·37 ±0·0 (Schroeder & Smith ) and 7·40 ±0·04 (Topal & Gul ). In contrast, this study showed that mean pH is slightly acidaemic (7·33 ±0·07) in anaesthetized pet rabbits.…”

“…Furthermore, because the rabbit has a superficial and easily identifiable central artery of the pinna (O'Malley ) (Fig ) and with the use of a portable clinical analyser, arterial blood sampling and analysis is relatively simple. ABG analysis has previously been studied in laboratory rabbits (Topal & Gul ). However, unlike laboratory subjects, pet rabbits are a heterogeneous population, more likely to suffer from undetected subclinical disease such as respiratory disease, dietary imbalances, or undetected dehydration and hypovolaemia.…”