RESUMO
Plasma potassium, heart rate, systolic and diastolic blood pressure were measured in adult surgical patients pre-treated with either terbutaline 1.25 mg (n = 10) or normal saline (n = 10) prior to and during general anaesthesia which included suxamethonium 1 mg kg-1. Neuromuscular blockade was then measured using a train-of-four technique. Plasma potassium was significantly lower before and during general anaesthesia in those patients who had received terbutaline but the rise following suxamethonium (measured at 1, 3, 5, 7, 10, 12, 15, 30 and 180 min after suxamethonium) was similar in both groups. Heart rate increased significantly in the treatment group both over time and compared to the control group. Onset time to maximum neuromuscular blockade and duration of blockade was shorter in the terbutaline-treated group.
Assuntos
Junção Neuromuscular/efeitos dos fármacos , Potássio/sangue , Succinilcolina/farmacologia , Terbutalina/farmacologia , Adulto , Anestesia Geral , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Junção Neuromuscular/fisiologia , Ortopedia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Terbutalina/administração & dosagemRESUMO
Vecuronium is an intermediate duration, non-depolarising muscle relaxant. When used during prolonged procedures, it may be given by intermittent injection, by continuous infusion or by a single very large dose at the start of anaesthesia. It may also be used to maintain relaxation after the initial use of a long-acting agent, such as pancuronium. This study demonstrates that the effect of a dose of vecuronium used in this fashion is increased when interaction with pancuronium takes place. The clinical and theoretical implications of this observation are discussed.