Behavior and changes in rectal temperature in dogs and cats undergoing hyperbaric oxygen therapy: clinical data review

The assessment of rectal temperature and behavior is an important parameter in all patients for whom hyperbaric oxygen (HBO₂) therapy is used. The study aims to verify if there is less reduction in body temperature after HBO₂ therapy in restless patients and their behavior during the therapeutic session. Clinical data from 217 HBO₂ therapy sessions with 2 to 2,5 atmospheres absolute (ATA) were reviewed under therapy protocols of 30 (P1) or 45 (P2) minutes, covering 29 canines and 13 felines. Behavioral data, initial rectal temperature (iRT), final (fRT), and variation between them (RTv) of each patient were recorded. Parameters of oxygen concentration, humidity, temperature, and chamber flow rate were also recorded. Three of 217 patients experienced major adverse effects (seizure and auto-trauma). 144/217 HBO₂ therapy session records were selected for statistical analysis. In P1 sessions, 33.3% of the canine and 33.3% of the feline patients were restless. In P2 sessions, 40.7% of the canine and 28.1% of the feline patients were restless. The study did not observe a correlation between vRT and patients' behavior (p> 0.089) or differences in vRT between quiet and restless patients. There was a difference between iRT and fRT only in canines submitted to P1 (p<0.001) and felines submitted to P2 (p<0.001). Older canine patients were more restless than young canine patients at P1 (p= 0.02). We conclude that there may be a reduction in the fRT of dogs and cats submitted to 2 ATA for 30 minutes and 2.5 ATA for 45 minutes, respectively.