Work

Comparing respiratory variables with circle, Bain and T-piece breathing systems in 5–10 kg dogs: a randomized crossover trial

Year: 2025

Type: article

Abstract: Objective To compare respiratory rate ( f R ), end expired carbon dioxide (PE′CO 2 ), tidal (VT) and minute ( E) volume through a Bain or circle breathing system against a T-piece control. Study Design : Randomised, non-blinded, crossover, clinical trial Animals or Animal population A group of 30, client-owned dogs (5–10 kg) undergoing general anaesthesia for elective procedures. Methods Equal groups of dogs were randomly allocated to the test breathing systems (either circle or Bain) then the order of breathing systems randomised (test or control first). All dogs received a standard anaesthetic protocol. Following induction, 10 minutes were allowed to achieve a stable anaesthetic plane. Measurements were obtained over a 5-minute window for each system. After each breathing system change 5 minutes was allowed for the dog to adjust. Measurements were compared using a paired student's t test or Wilcoxon rank test. Results The circle PE′CO 2 (6.04 ± 0.64 kPa), VT (12.1 ± 3.9 mL kg -1 ) and E [116.7 (97.5–166.0) mL kg -1 minute -1 ] were significantly higher ( p = ≤ 0.001, 0.035 and 0.002 respectively) than the T-piece PE′CO 2 (5.31 ± 0.78 kPa), VT [10.6 (7.7–13.3) mL kg -1 ] and E [107.8 (77.3–131.9) mL kg -1 minute -1 ]. The Bain PE′CO 2 (5.22 ± 0.98 kPa) was significantly lower ( p = 0.032) and the VT (7.1 ± 2.7 mL kg -1 ) significantly higher ( p = 0.041) than the T-piece PE′CO 2 (5.61 ± 0.90 kPa) and VT [6.6 (4.8–7.0) mL kg -1 ]. Between the Bain and T-piece there was no significant difference in E. f R was similar in both systems compared with the control. Conclusions and Clinical Relevance Whilst differences were found between both test systems and the control, the clinical consequences appear minimal. Both circle and Bain, appear suitable for use in healthy 5–10 kg dogs as overall ventilatory function was adequate.

Source: Veterinary Anaesthesia and Analgesia

DOI: 10.1016/j.vaa.2025.06.002

Authors: Andrew G. Murray, Kerry Woodhouse, Pamela J. Murison

Institution: University of Glasgow

Language: English

Topic: Veterinary Pharmacology and Anesthesia

Subfield: Small Animals

Field: Veterinary

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,000