D. Yorukoglu et al., Comparison of intravenous metoprolol, verapamil and diltiazem on the attenuation of haemodynamic changes associated with tracheal extubation, EUR J ANAES, 16(7), 1999, pp. 462-467
Changes in heart rate, systolic, diastolic and mean blood pressure were mea
sured after extubation in 60 ASA Grade I and II patients to assess the effe
cts of diltiazem (0.2 mg kg(-1)), verapamil (0.05 mg kg(-1)) and metoprolol
(0.02 mg kg(-1)) given as a bolus 2 min before tracheal extubation. All th
e haemodynamic variables measured increased significantly after extubation
in the control and diltiazem groups when compared with the base-line record
ings (P < 0.05). Metoprolol effectively blocked the increases in heart rate
after extubation and the increase in blood pressure in this group was less
when compared with the control group (P < 0.05). Verapamil alleviated the
increase in both heart rate and blood pressure. However, profound hypotensi
on and bradycardia requiring therapy, occurred in the verapamil group. For
this reason, careful observation is necessary when using verapamil and the
routine use of this drug in patients with coronary artery disease requires
further studies.