Haemodynamic effects and uptake of enflurane in patients undergoing cardiac surgery: good versus poor myocardial function.
We measured haemodynamic effects and uptake of enflurane in patients undergoing cardiac surgery utilizing a standard anaesthetic technique of fentanyl 15 mcg/kg nitrous oxide 50%/enflurane 1%. We divided 22 patients preoperatively into two groups according to standard criteria: good and poor myocardial function. Regression lines could be drawn illustrating the relationship of cardiac output and uptake (at 1 minute: r = -0.56, P less than 0.01; at 5 minutes: r = -0.43, P less than 0.05; at 30 minutes: r = -0.31, P = 0.08). Although patients with poor myocardial function had decreased uptake of enflurance (approximately 10-20%), this did not reach statistical significance. Fentanyl/nitrous oxide/enflurane anaesthesia provided stable haemodynamics, even in patients with poor myocardial function. Both groups had a shunt fraction of approximately 10% and an arterial: end-tidal carbon dioxide difference of approximately 3-4 mmHg.
Myles
P S
PS
Anaesthetic Department, Royal Perth Hospital, Western Australia.
Storer
R
R
Millar
C
C
D000769:Anesthesia, Inhalation; D001831:Body Temperature / Q000187:drug effects; D002245:Carbon Dioxide / Q000032:analysis; D002302:Cardiac Output / Q000187:drug effects; D006348:Cardiac Surgical Procedures; D004737:Enflurane / Q000032:analysis / Q000493:pharmacokinetics* / Q000494:pharmacology*; D005283:Fentanyl / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects / Q000503:physiopathology; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008875:Middle Aged; D009609:Nitrous Oxide / Q000032:analysis / Q000494:pharmacology*; D011659:Pulmonary Gas Exchange; D013990:Tidal Volume; D016276:Ventricular Function / Q000187:drug effects / Q000502:physiology*
D002245:Carbon Dioxide; D004737:Enflurane; D009609:Nitrous Oxide; D005283:Fentanyl