title: Postoperative hypertension: a comparison of diltiazem, nifedipine, and nitroprusside.
abstract: In previous studies, the treatment of postoperative hypertension with sodium nitroprusside induced ischemic metabolism without a decrease in coronary sinus blood flow. In contrast, the calcium antagonists diltiazem and nifedipine reduce blood pressure and may improve myocardial metabolism. A prospective randomized trial was performed in 62 patients, in whom hypertension developed (mean arterial pressure greater than 95 mm Hg) after coronary bypass procedures, to compare diltiazem (n = 22), nifedipine (n = 20), and nitroprusside (n = 20). All three agents reduced blood pressure equally (p less than 0.0001, by analysis of variance). Heart rate decreased with diltiazem (p = 0.006) but increased with nifedipine and nitroprusside (p less than 0.05). Left ventricular diastolic function (the relation between left atrial pressure and left ventricular end-diastolic volume) was not changed with the three drugs. Systolic function (the relation between systolic blood pressure and left ventricular end-systolic volume) was depressed with diltiazem (p = 0.05 by analysis of covariance) and nifedipine (p = 0.05) but not with nitroprusside. Myocardial performance (the relation between left ventricular stroke work index and end-diastolic volume) was depressed most by diltiazem (p = 0.001 by analysis of covariance), and to a lesser extent with nifedipine (p = 0.03), but not with nitroprusside. Myocardial lactate flux in response to the stress of atrial pacing decreased with nitroprusside but not with diltiazem or nifedipine (p = 0.03 by analysis of variance). Diltiazem and nifedipine are effective agents for treating postoperative hypertension after coronary artery bypass operations.
authors.affiliation: Division of Cardiovascular Surgery, Toronto General Hospital, Ontario, Canada.
authors.forename: J C
authors.initials: JC
authors.lastname: Mullen
authors.forename: D R
authors.initials: DR
authors.lastname: Miller
authors.forename: R D
authors.initials: RD
authors.lastname: Weisel
authors.forename: P L
authors.initials: PL
authors.lastname: Birnbaum
authors.forename: K H
authors.initials: KH
authors.lastname: Teoh
authors.forename: M M
authors.initials: MM
authors.lastname: Madonik
authors.forename: J
authors.initials: J
authors.lastname: Ivanov
authors.forename: D T
authors.initials: DT
authors.lastname: Laidley
authors.forename: P
authors.initials: P
authors.lastname: Liu
authors.forename: S J
authors.initials: SJ
authors.lastname: Teasdale
mesh_terms: D002986:Clinical Trials as Topic; D001026:Coronary Artery Bypass; D004110:Diltiazem / Q000627:therapeutic use*; D005260:Female; D005292:Ferricyanides / Q000627:therapeutic use*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D009543:Nifedipine / Q000627:therapeutic use*; D009599:Nitroprusside / Q000627:therapeutic use*; D011183:Postoperative Complications / Q000188:drug therapy*; D011446:Prospective Studies; D011897:Random Allocation
chemical_list: D005292:Ferricyanides; D009599:Nitroprusside; D004110:Diltiazem; D009543:Nifedipine