Pharmacokinetic-based total intravenous anaesthesia using remifentanil and propofol for surgical myocardial revascularization.
OBJECTIVE
We investigated the following aspects of pharmacokinetic-guided total intravenous anaesthesia with remifentanil and propofol in patients undergoing surgical myocardial revascularization: anaesthetic efficacy, haemodynamic effects, impact on extubation of the trachea and analgesia after operation.


METHODS
Thirty-two patients undergoing on-pump coronary bypass surgery received intravenous anaesthesia with remifentanil and propofol. Both drugs were dosed and titrated based on computer-assisted pharmacokinetic models to maintain constant plasma concentrations. The propofol target plasma concentration was 1.2 microg mL(-1) throughout the procedure. A remifentanil target plasma concentration of 8 ng mL(-1) was achieved over 2 min for induction. After tracheal intubation, the opioid plasma concentration was reduced to 4 ng mL(-1), and then titrated up to 8 ng mL(-1) during surgery. Postoperative analgesia was managed with remifentanil infusion until 4 h after tracheal extubation, and a continuous infusion of tramadol was started 1 h before the remifentanil was stopped.


RESULTS
After induction of anaesthesia, heart rate (-20%) and cardiac index (-6%) decreased significantly. No hypotensive episodes (mean arterial pressure < 60 mmHg) occurred. Intraoperative haemodynamics were stable. Three cases of myocardial ischaemia were detected: two by transoesophageal echocardiography and one with ST-segment monitoring. The duration of postoperative mechanical ventilation of the lungs was 95 +/- 13 min and the time to extubation was 150 +/- 18 min. Postoperative analgesia was satisfactory in all patients.


CONCLUSIONS
Pharmacokinetic-based total intravenous anaesthesia with remifentanil and propofol provides adequate anaesthesia during coronary surgery with cardiopulmonary bypass and allows safe early extubation after operation.
Guarracino
F
F
Umberto I Hospital, Department of Cardiac Anaesthesia and Intensive Care, Venezia-Mestre, Italy. fabiodoc64@hotmail.com
Penzo
D
D
De Cosmo
D
D
Vardanega
A
A
De Stefani
R
R
D000328:Adult; D000368:Aged; D019162:Anesthetics, Combined / Q000008:administration & dosage / Q000494:pharmacology*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000494:pharmacology*; D002302:Cardiac Output / Q000187:drug effects; D001026:Coronary Artery Bypass; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007430:Intraoperative Care; D008297:Male; D008875:Middle Aged; D010880:Piperidines / Q000008:administration & dosage / Q000494:pharmacology*; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D000077208:Remifentanil
D019162:Anesthetics, Combined; D018686:Anesthetics, Intravenous; D010880:Piperidines; D000077208:Remifentanil; D015742:Propofol