Esmolol for potentiation of nitroprusside-induced hypotension: impact on the cardiovascular, adrenergic, and renin-angiotensin systems in man.
Esmolol infusion at rates of 200, 300, and 400 micrograms.kg-1.min-1 was used to potentiate hypotension (mean arterial pressure = 60 mm Hg) induced with sodium nitroprusside (SNP) in 10 male patients undergoing radical cancer surgery during nitrous oxide-oxygen and fentanyl anesthesia. Heart rate (HR), blood pressure (radial arterial catheter), and plasma levels of renin activity (PRA), norepinephrine (N), epinephrine (E), and dopamine (D) were measured: 1) while patients were awake; 2) after induction of anesthesia (nitrous oxide, 60% in oxygen, fentanyl = 5 micrograms/kg followed by an infusion at 10 micrograms.kg-1.hr-1); 3) after surgery had begun; 4) after 20 minutes of SNP-induced hypotension; 5) after 20 minutes of esmolol at each of the above infusion rates; and 6) after the completion of surgery. Compared to awake values, SNP-induced hypotension (mean infusion rate = 3.1 micrograms.kg-1.min-1 +/- 0.6 SE) during surgery resulted in significant (P less than 0.05) increases in heart rate, PRA, N, and D. Infusion of esmolol resulted in significant (P less than 0.05) dose-dependent reductions in SNP requirement to maintain MAP = 60 mm Hg. At 200 micrograms.kg-1.min-1, SNP requirement was 2.1 micrograms.kg-1.min-1 +/- 0.4, at 300 micrograms.kg-1.min-1, it was 1.0 micrograms.kg-1.min-1 +/- 0.2, and at 400 micrograms.kg-1.min-1, was 0.5 micrograms.kg-1.min-1 +/- 0.3. Concomitant with the decrease in SNP requirement, there were significant reductions in HR and PRA at all infusion rates of esmolol.(ABSTRACT TRUNCATED AT 250 WORDS)
Edmondson
R
R
Department of Anesthesiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021.
Del Valle
O
O
Shah
N
N
Wong
G
G
Dwyer
D
D
Matarazzo
D
D
Thorne
A
A
Coffey
C
C
Bedford
R
R
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D002395:Catecholamines / Q000097:blood; D004357:Drug Synergism; D005292:Ferricyanides / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007023:Hypotension, Controlled; D008297:Male; D008875:Middle Aged; D009599:Nitroprusside / Q000008:administration & dosage / Q000494:pharmacology*; D010100:Oxygen / Q000097:blood; D011412:Propanolamines / Q000008:administration & dosage / Q000494:pharmacology*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System / Q000187:drug effects*; D013997:Time Factors
D000319:Adrenergic beta-Antagonists; D002395:Catecholamines; D005292:Ferricyanides; D011412:Propanolamines; D011943:Receptors, Adrenergic, beta; D009599:Nitroprusside; D012083:Renin; C036604:esmolol; D010100:Oxygen