Intravenous Beta-blockade for Improvement of Autonomic Activity

Hypertension Clinical Trial

Official title:

Beta-adrenoceptor Blockade Prior to Induction of Anesthesia for Improvement of Depressed Autonomic Regulation

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00700466
• Other study ID #: Hanss_EA 162/07
• Status: Completed
• Phase: N/A
• First received: June 13, 2008
• Last updated: January 15, 2010
• Start date: March 2008
• Est. completion date: November 2009

Study information

• Verified date: February 2009
• Source: University of Schleswig-Holstein
• Contact: n/a
• Is FDA regulated: No
• Health authority: Germany: Ethics Commission
• Study type: Observational

Clinical Trial Summary

Chronic beta-adrenoceptor blockade is known to improve outcome of high risk patients whereas amelioration of autonomic activity was demonstrated to be a major cause of outcome improvement. Therefore, perioperative beta-adrenoceptor blockade is recommended in patients with Revised Cardiac Risk Index score of three or greater. The investigators hypothesise that preoperative intravenous beta-adrenoceptor blockade for treatment of hypertension and/or tachycardia improves autonomic activity reflected by increase of Total Power of Heart Rate Variability.

Material and Methods: After IRB approval 20 patients scheduled for elective cardiac surgery were included into the study. Routine medication was continued throughout the study as recommended by the guidelines. HRV (TP and Low to High Frequency ratio (LF/HF) reflecting sympathetic to parasympathetic balance) was analysed prior to induction of general anesthesia and beta-adrenoceptor blockade in all patients (Baseline). Patients were assigned by their baseline hemodynamics. Patients with hypertension (systolic blood pressure > 140mmHg or diastolic blood pressure > 90mmHg) or tachycardia (heart rate > 80bpm) were assigned to group BETA-BLOCK. In this group metoprolol-boli (2mg) were administered intravenously in stepwise manner until hemodynamic values decreased to normal. Total dosage was recorded. After normalisation of hemodynamics, second HRV analysis was performed (Intervention). Normotensive and normocardic patients were assigned to group CONTROL. No intervention was performed. Statistics: Mann Whitney U test for comparison between groups and between events Baseline and Intervention within group BETA-BLOCK, p<0.05.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 100
• Est. completion date: November 2009
• Est. primary completion date: March 2009
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Patients scheduled for coronary artery bypass surgery

• Ejection fraction > 30 %

• Informed consent

Exclusion Criteria:

• Emergency cases

• Myocardiac infraction within 4 weeks

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Heart Rate Variability
• Hypertension
• Tachycardia

Intervention

Drug:
• i.v. beta-blocker infusion (metoprolol)
A beta-blocker (metoprolol) will be infused for treatment of hypertension and/or tachycardia prior to induction of anesthesia aiming at decrease of blood pressure and heart rate to normal limits

Locations

Country	Name	City	State
Germany	University Hospital Schleswig-Holstein, Campus Kiel, Germany	Kiel	Schleswig-Holstein

Sponsors (1)

Lead Sponsor	Collaborator
University of Schleswig-Holstein

Country where clinical trial is conducted

Germany, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Improvement of heart rate variability reflecting autonomic activity in the course of i.v. beta-blockade		Baseline, after i.v. beta-blockade, 6 months after discharge	No
Secondary	Hospital stay, one-year cardiac mortality and morbidity after discharge		Postoperatively until discharge, between discharge and 1 year after discharge	No