Effect of inhaled salbutamol on whole-blood potassium concentrations in healthy cats.

Abstract

ObjectivesThis study aimed to determine the effect of inhaled salbutamol on blood potassium concentrations in normokalemic cats, evaluate whether effects are dose dependent and assess whether it affects heart rate and blood glucose concentrations.MethodsThe study was a prospective, open-label, two-way crossover trial. A total of 11 healthy cats were randomly assigned to two groups: one received a low dose of 100 µg salbutamol (Low group) and the other a high dose of 200 µg (High group). After a washout period of 15-21 days, the Low group received the high dose and the High group received the low dose. Blood potassium and glucose concentrations and heart rates were measured at baseline and 10, 20, 30, 45, 60, 90, 120, 150 and 180 mins after salbutamol administration.ResultsPotassium concentrations significantly decreased over time after the administration of salbutamol in both groups (P <0.001). Salbutamol dose (µg/kg) and dose-time interaction had no significant effect on potassium concentration (P = 0.082 and P = 0.54, respectively). In the High group, mean potassium concentrations were significantly lower at 30-150 mins after salbutamol administration compared with baseline (P <0.011), and the mean decrease in potassium concentration from baseline to nadir was -0.69 ± 0.17 mmol/l. In the Low group, mean potassium concentrations were lower at 20-90 mins after salbutamol administration; however, these differences were not statistically significant (P >0.05). The administration of salbutamol did not appear to affect heart rate and blood glucose.Conclusions and relevanceIn healthy cats, salbutamol administration led to a small and variable, non-dose-dependent decrease in potassium levels, suggesting that individual susceptibilities may affect the response to the potassium-lowering effects of salbutamol. The doses used in this study seemed safe. Further studies are needed to determine the optimal dosage of salbutamol and its effect on hyperkalemic cats.