Cardiovascular effects of intravenous propofol administered at two infusion rates:.a transthoracic echocardiographic study

We assessed the hae m odynamic changes after a p ropofol infusio n at two rates in lo w- risk unpr emedicated patients (ASA I - II ). To determi ne contrac tility changes and loadin g conditio ns, we measur ed the ejection fraction, end- systoli c quotient and fractio nal shortening on transth orac ic echocardiograms. We studi ed 40 patie nts und ergoin g peripheral neu rosur gical procedu res und er general anaesth esia indu ced by prop ofo l alone (tot al dose 2.5 mg.k-g assigned to receive propofol at an infusio n rate of 10 m g.s- l ; o r 2 mg-.s 1) . Patients were rand oml y . H aemodynami c data we re recorded sim ultaneo usly imm ediately before propofol infusio n, at the end of infusio n, and 5 and 1O min after th e infusion end ed. T he higher infusio n rate indu ced a larger decrease in mean art eria!