Trial Assessing the Effect of Preoperative Furosemide on Intraoperative Blood Pressure

Phase 4

Completed

• Conditions: Hypertension; Hypotension; Edema; Congestive Heart Failure
• Interventions: Drug: furosemide; Drug: placebo

• Registration Number: NCT00115726
• Lead Sponsor: University of Calgary

Brief 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.

Detailed 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.

Study Timeline

• Study Start: 2000-09
• Study First Submitted: 2005-06-23
• Study First Submitted QC: 2005-06-23
• Study First Posted: 2005-06-24
• Primary Completion: 2006-02
• Study Completion: 2007-04
• Status Verified: 2008-02
• Last Update Submitted: 2008-02-20
• Last Update Posted: 2008-02-22

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 198

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

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
1	furosemide	furosemide
2	placebo	placebo

Primary Outcome Measures

Name	Time	Method
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

Secondary Outcome Measures

Name	Time	Method
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
(2) Total cardiovascular complications: composite of acute myocardial infarction, angina, stroke/TIA, arrhythmia, congestive heart failure or cardiac death.	hospital stay

Trial Locations

Locations (3)

The Cleveland Clinic Foundation; 🇺🇸 Cleveland, Ohio, United States

Foothills Hospital; 🇨🇦 Calgary, Alberta, Canada

University of Western Ontario; 🇨🇦 London, Ontario, Canada