Intravenous Beta-blockade for Improvement of Autonomic Activity

NCT ID: NCT00700466

Last Updated: 2010-01-18

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 100 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2008-03-31
• Study Completion Date: 2009-11-30

Brief 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.

Conditions

Hypertension; Tachycardia; Heart Rate Variability

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

1

Patients with hypertension and/or tachycardia prior to induction of anesthesia requiring i.v. beta-blockade for treatment of raised hemodynamic

i.v. beta-blocker infusion (metoprolol)

Intervention Type: DRUG

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

2

Patients with normal hemodynamic values prior to induction of anesthesia not requiring treatment

No interventions assigned to this group

Interventions

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

Intervention Type: DRUG

Other Intervention Names

Metorpolol, Lopresor(R)

Eligibility Criteria

Inclusion Criteria

• Patients scheduled for coronary artery bypass surgery
• Ejection fraction > 30 %
• Informed consent

Exclusion Criteria

• Emergency cases
• Myocardiac infraction within 4 weeks

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University Hospital Schleswig-Holstein

OTHER

Sponsor Role: lead

Responsible Party

University Hospital Schleswig-Holstein, Campus Kiel, Germany

Principal Investigators

Robert Hanss, MD

Role: PRINCIPAL_INVESTIGATOR

Consultant in Anesthesiology, Dep. of Anesthesiology and Intenisve Care Medicine, University Hospital Schleswig-Holstein, Campus Kiel, Germany

Locations

University Hospital Schleswig-Holstein, Campus Kiel, Germany

Kiel, Schleswig-Holstein, Germany

Countries

Germany

Other Identifiers

Hanss_EA 162/07

Identifier Type: -

Identifier Source: org_study_id