Trial Assessing the Effect of Preoperative Furosemide on Intraoperative Blood Pressure

Hypertension Clinical Trial

Official title:

Randomized Controlled Trial Assessing the Effect of Preoperative Furosemide on Intraoperative Blood Pressure

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00115726
• Other study ID #: 15326
• Secondary ID: 15326
• Status: Completed
• Phase: Phase 4
• First received: June 23, 2005
• Last updated: February 20, 2008
• Start date: September 2000
• Est. completion date: April 2007

Study information

• Verified date: February 2008
• Source: University of Calgary
• Contact: n/a
• Is FDA regulated: No
• Health authority: Canada: Health Canada
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to determine whether continuing or discontinuing furosemide (a diuretic) on the day of elective noncardiac surgery for those who take furosemide on a chronic basis, causes more intraoperative hypotension (low blood pressure) during surgery. Our hypothesis is that the usual practice of continuing furosemide on the day of surgery would contribute to more hypotension during surgery than discontinuing furosemide.

Description:

A significant proportion of patients who undergo surgery take medications on a chronic basis. Little is known about the effects of these medications on the successful conduct of anesthesia and surgery. Diuretics like furosemide may contribute to low blood pressure during surgery, an outcome associated with cardiovascular complications. However, many patients are recommended to take their diuretics on the day of surgery. We wished to determine if preoperative administration of furosemide contributes to intraoperative hypotension compared to placebo.

Comparison: We conducted a randomized, double blind placebo controlled trial to compare the effect of furosemide with that of placebo on intraoperative hypotension using intraoperative blood pressure recordings in patients who take furosemide chronically and were undergoing noncardiac surgery.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 198
• Est. completion date: April 2007
• Est. primary completion date: February 2006
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• All adults referred to preoperative assessment clinics by surgeons for elective non-cardiac surgery who routinely take furosemide.

• Participants must also be able to give informed consent

Exclusion Criteria:

• Less than 18 years of age

• Have comorbid conditions with which brief periods of hypotension may be particularly harmful such as: 1) pregnancy; 2) baseline hypotension (systolic <100 mmHg at the preoperative assessment clinic); 3) autonomic dysfunction; 4) severe aortic stenosis.

• Patients who take furosemide only on an 'as needed basis' rather than 'regularly'.

• Those patients who take less than 10 mg of furosemide daily

• Those patients who are undergoing local anesthetic only surgical procedures

• Patients who are unwilling or unable to give informed consent.

Study Design

Allocation: Randomized, Endpoint Classification: Safety Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Congestive Heart Failure
• Edema
• Heart Failure
• Hypertension
• Hypotension

Intervention

Drug:
• furosemide
for patients on chronic furosemide therapy, patients are randomized to furosemide (at their previous dose) or placebo (given in identical form to ensure masking)
• placebo
patients will be given placebo capsules (identical to experimental arm in color) at the equivalent dose as to their chronic furosemide therapy.

Locations

Country	Name	City	State
Canada	Foothills Hospital	Calgary	Alberta
Canada	University of Western Ontario	London	Ontario
United States	The Cleveland Clinic Foundation	Cleveland	Ohio

Sponsors (2)

Lead Sponsor	Collaborator
University of Calgary	The Centre for the Advancement of Health

Countries where clinical trial is conducted

United States,  Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Proportion of patients developing hypotension during the operative period. Hypotension is defined based on blood pressure criteria (systolic BP <90 mmHg or 35% drop in mean arterial pressure) (or vasopressor treatment during surgery).		hospital stay	Yes
Secondary	Patients will be followed up for the duration of their hospital stay for the following endpoints: (1) Development of congestive heart failure exacerbation		hospital stay	Yes
Secondary	(2) Total cardiovascular complications: composite of acute myocardial infarction, angina, stroke/TIA, arrhythmia, congestive heart failure or cardiac death.		hospital stay	Yes