AVALIAÇÃO ECOCARDIOGRÁFICA DE EQÜINOS PRÉ-MEDICADOS COM N-BUTILBROMETO DE HIOSCINA E SEDADOS COM ROMIFIDINA

Abstract

The cardiovascular effects of the hyoscine and romifidine association were appraised in six adult horses submitted to two different treatments, TSR e THR. In the TSR the animals were injected with saline solution (NaCl 0.9%) intravenously simulating the hyoscine volume. Hyoscine (0.14 mg/kg) was administered intravenously in the THR. In both treatments the respective solutions were administered five minutes before the intravenous injection of romifidine (0.08 mg/kg). The ejection fraction, shortening fraction and the cardiac output were echocardiographically analyzed. The blood pressure was measured by catheterization of the left carotid artery. The cardiac function was registered electrocardiographically. The analyzed parameters were measured before (M0) and five minutes after the administration of the saline solution or hyoscine (M1). The parameters were measured at 10 (M2), 15 (M3), 30 (M4), 45 (M5) and 60 (M6) minutes after the romifidine injection. The final results consigned that the hyoscine prevents bradicardy and the second-degree heart block, with a significant increase in heart frequency, cardiac output and blood pressure. The ejection fraction and the shortening fraction didn’t have significant changes. The echocardiographic evaluation of equine pretreated with hyoscine and sedated with romifidine should be interpreted with caution, because the cardiac changes observed by the effects of romifidine are suppressed by the hyoscine. Key-words: Echocardiography, horse, hyoscine, romifidine.