title: Myocardial uptake and release of lactate after high dose neurolept endotracheal intubation in coronary surgery.
abstract: To evaluate the relationship between the hemodynamic and ECG variables used in routine surveillance of coronary surgery and myocardial lactate metabolism, 23 middle-aged, male, beta 1-blocked patients about to undergo coronary surgery were monitored before and after endotracheal intubation with high dose (30 micrograms/kg) fentanyl-midazolam anesthesia. The induction of anesthesia was followed by a mean arterial pressure decrease (from 98 +/- 4 to 76 +/- 3 mm Hg) and heart rate increase (from 53 +/- 3 to 66 +/- 2 beats/min). After intubation the hemodynamic variables were stable except for a further, transient increase in heart rate (to 69 +/- 2 beats/min). The myocardial uptake of lactate decreased after intubation, from 48 +/- 5 mumol/min to a lowest level of 24 +/- 3 mumol/min. A lactate release was exhibited in 7/23 patients (30%). No ST-segment changes were observed. The correlation between the myocardial lactate uptake/release and hemodynamic or ECG variables was unimpressive or non-existent (r < or = 0.20). Thus, a reduced uptake and even a release of lactate occurred irrespective of the ST-segment, heart rate, or systemic or pulmonary artery pressures. In conclusion, endotracheal intubation in patients with coronary disease was consistently (17/23 patients) followed by a reduced myocardial uptake of lactate, in spite of high dose neurolept anesthesia and beta 1-blockade. This metabolic event was not consistently related to hemodynamic changes.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, University Hospital, Uppsala, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Thorelius
authors.forename: O
authors.initials: O
authors.lastname: Wesslén
authors.forename: J A
authors.initials: JA
authors.lastname: Björkman
authors.forename: R
authors.initials: R
authors.lastname: Ekroth
authors.forename: P O
authors.initials: PO
authors.lastname: Joachimsson
authors.forename: G
authors.initials: G
authors.lastname: Ronquist
authors.forename: H
authors.initials: H
authors.lastname: Tydén
mesh_terms: D000319:Adrenergic beta-Antagonists; D000368:Aged; D000769:Anesthesia, Inhalation; D003327:Coronary Disease / Q000503:physiopathology* / Q000601:surgery*; D004562:Electrocardiography; D005283:Fentanyl; D006439:Hemodynamics; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects; D007773:Lactates / Q000378:metabolism*; D019344:Lactic Acid; D008297:Male; D008874:Midazolam; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009206:Myocardium / Q000378:metabolism*; D013312:Stress, Physiological / Q000209:etiology / Q000503:physiopathology
chemical_list: D000319:Adrenergic beta-Antagonists; D007773:Lactates; D019344:Lactic Acid; D008874:Midazolam; D005283:Fentanyl