Assuntos
Anestésicos Locais/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Anestésicos Locais/uso terapêutico , Catecolaminas/efeitos adversos , Sistema Nervoso Central/efeitos dos fármacos , Glicosídeos Digitálicos/efeitos adversos , Coração/efeitos dos fármacos , Humanos , Hipóxia , Nervos Periféricos/efeitos dos fármacosAssuntos
Ilustração Médica , Arte , Livros Ilustrados , Métodos , Fotografação , Impressão , RadiografiaAssuntos
Anestésicos Locais/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Fenitoína/uso terapêutico , Simpatolíticos/uso terapêutico , Animais , Arritmias Cardíacas/induzido quimicamente , Cães , Etanolaminas/uso terapêutico , Lidocaína/uso terapêutico , Ouabaína , Prilocaína/uso terapêuticoRESUMO
The drug 4-aminopyridine (4-AP) at a dose of 0.2 mg . kg-1 body weight intravenously is an effective antagonist of non-depolarizing neuromuscular blockade. We studied its cardiovascular effects in the canine heart using a right-heart bypass with extracorporeal circulation in seven dogs. This study demonstrates that 4-aminopyridine significantly augments arterial blood pressure, left ventricular dp/dt maximum, as well as left ventricular pressure at dp/dt mx. The highest values were obtained between two and 20 minutes after administration of 4-AP. Left ventricular end-diastolic pressure diminished slightly, but this was not statistically significant. Although the exact mechanism of action of 4-AP is not known, its positive inotropic effects may be of value in the reversal of non-depolarizing neuromuscular blockade in patients with impaired myocardial function of diverse aetiologies and it would be contra-indicated in patients with arterial hypertension and/or coronary artery disease.