Fenoterol e salbutamol via inalatória em cães: aspectos clínico, hemogasométrico e eletrocardiográfico / Fenoterol and salbutamol inhalation in dogs: clinical, haemogasometric and electrocardiographic aspects

Avaliaram-se, por meio de exame clínico, hemogasométrico e eletrocardiográfico, os efeitos do salbutamol e do fenoterol, administrados por via inalatória em cães. Doze cães foram distribuídos em dois grupos: os do grupo FE receberam fenoterol na dose de 2 gotas/5kg de peso vivo, diluídas em solução de cloreto de sódio 0,9 por cento por aparelho de inalação, e os do grupo SA receberam salbutamol pelo dosador de aerossol, na dose de 100mg. Foram avaliados: frequência cardíaca (FC), frequência respiratória (FR), temperatura retal (TR), pressão arterial sistólica (PAS), hemogasometria e eletrocardiograma antes e após 30min, duas horas e seis horas do uso dos fármacos. Discreta estimulação cardíaca ocorreu nos animais do grupo SA duas horas após sua administração em relação ao momento-controle, e tremores foram predominantes nestes animais. Diminuição da PAS e aumento da FR foram observados nos dois grupos, e não houve alteração significativa da onda T, da hemogasometria e do eletrocardiograma em ambos os grupos. O fenoterol provocou menor estimulação cardíaca e menos tremores comparado ao salbutamol, foi mais seguro e houve maior facilidade, menor custo e menor gasto de tempo na administração do salbutamol por inalador dosimetrado em relação ao fenoterol por nebulização.(AU)

Through physical examination, blood gas and the electrocardiographic effects of salbutamol and fenoterol, administered by inhalation in dogs was assessed. Twelve dogs were distributed into two groups: EF group animals received a fenoterol dose of 2 drops/5kg bodyweight, diluted in sodium chloride 0.9 percent inhalation device and animals in the SA group received salbutamol through aerosol feeder at a dose of 100µg. Rectal temperature (RT), heart rate (HR), respiratory rate (RR), systolic blood pressure (SBP), blood gas and electrocardiogram before and after 30min., 2h and 6 h after drug were evaluated. Mild cardiac stimulation occurred in SA group animals 2 hours after its administration compared to the control group, and tremors were predominant in these animals. A decrease in SBP and an increase in RR were observed in both animal groups and no significant alteration of the T wave in the electrocardiogram and blood gas analysis in both groups were observed. The fenoterol caused less cardiac pacing and shivering compared to salbutamol, which was more secure. However, there was more ease, lower cost and less time spent in the administration of salbutamol administered through metered-dose inhaler compared to fenoterol nebulization.(AU)

Validation of new analytical methodology for determining fenoterolhydrobromide by HPLC: application in pharmaceutical products

Fenoterol hydrobromide is a B2-adrenergic agonist agent used for asthma and chronic obstructive pulmonary disease treatment. HPLC methodology was developed and validated for quantitative determination of fenoterol hydrobromide. The methodology was achieved by using a reversed-phase C18column, (150 mm ¡Á 3.9 mm i.d., 5 ¦Ìm) Thermo. The mobile phase was consisted of acetonitrile: water(30:70, v/v) with 0,1% triethylamine, pH adjusted to 5.0 with formic acid and flow rate of 1.0 mL.min-1with UV detection at 276 nm. The concentration range was from 0.025 to 0.15 mg.mL-1, and the correlation coefficient of analytical curve was >0.999. The detection limit and the quantifying limit (QL) were 0.003mg.mL-1 and 0.012 mg.mL-1, respectively. Intra- and interday relative standard deviations were ¡Ü2.0%. Themetho dology accuracy showed the percentage mean of 99.53%. The described technique was found to be simple, rapid, precise, accurate and sensitive; the advantages over the others current methodologies arethe low-cost and low-polluting conditions. Owing to its simplicity and reliable results, this methodology is suitable to be used in quality control of pharmaceutical drugs containing fenoterol hydrobromide as active componente. (AU)