Passive Leg Raising Test to Predict Hypotension During Induction of Anesthesia in Patients Undergoing Cardiac Surgery

Hypotension frequently occurs during anesthesia induction. Preload decrease by anesthetics was often considered as one of main causes for this hypotension. However, the studies on this topic have been lacking. Dynamic preload indices are more suitable than static preload indices to predict the effect of preload changes. And, recently, passive leg raising test showed successful results to predict fluid responsiveness in patient with spontaneous ventilation.

The investigators hypothesized that hypotension after induction of anesthesia is caused by decrease of preload by anesthetics and passive leg raising test could predict this hypotension. In this study, the investigators will try to evaluate whether passive leg raising induced hemodynamic changes could predict hypotension during anesthesia induction.

Study Overview

• Status: Completed
• Conditions: Ischemic Heart Disease; Cardiac Valve Disease
• Intervention / Treatment: Procedure: passive leg raising (45 degree leg elevation for 1-2 min)

Detailed Description

In this randomized controlled clinical trial, the investigators hypothesized that passive leg raising induced changes in hemodynamic parameters could predict the hypotension during anesthesia induction. To evaluate this, before anesthesia, the investigators will conduct passive leg raising test. At first, the patient's trunk was elevated 45 degrees for the first set of measurements. Then, the lower limbs were raised to a 45° angle while the patient's trunk was lowered to a supine position to measure peak CO (usually within 1-2 min). Hemodynamic profiles planned to be measured are mean arterial pressure, heart rate, cardiac index, stoke volume and stroke volume variation. After this, the occurrence of hypotension (systolic blood pressure < 90mmHg or mean arterial pressure decrease > 30% of baseline) will be recorded during the time from anesthesia induction to surgical skin incision. Hypotension will be treated by a standardized method. If heart rate (HR) is less than 70 beats/min, 5mg of ephedrine will be administered and if HR is greater than 70 beats/min, 30 mcg of phenylephrine will be administered. This will repeated until hypotension subsided. Refractory hypotension will be defined as continuous hypotension despite the total infused dose of ephedrine > 0.5 mg/kg or phenylephrine > 4 mcg/kg. The ability to predict hypotension and refractory hypotension during anesthesia induction by passive leg raising test will be evaluated by receiver operating characteristic curve analysis.

• Study Type: Interventional
• Enrollment (Actual): 42
• Phase: Phase 2

Contacts and Locations

Study Locations

• Korea, Republic of
  • Seoul, Korea, Republic of
    • Seoul National University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• adult patients undergoing elective cardiac surgery

Exclusion Criteria:

• arrhythmias
• documented peripheral artery disease
• severe pulmonary disease
• heart failure
• unstable angina
• preoperative use of inotropics or mechanical assist device
• use of angiotensin converting enzyme inhibitors
• expected intubation difficulty or gastric reflux disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Passive Leg Raising; elevation of both legs to a 45 degrees for about 1-2 minute before anesthesia induction	Procedure: passive leg raising (45 degree leg elevation for 1-2 min); the patient's trunk was elevated 45 degrees for the first set of measurements. Then, the lower limbs were raised to a 45° angle while the patient's trunk was lowered to a supine position to measure peak CO (usually within 1-2 min); Other Names: PLR

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The area under ROC curve to predict hypotension and refractory hypotension	area under ROC curve of HR, SV, SVV, and CI changes during PLR to predict hypotension and refractory hypotension	30 min around passive leg raising test

Collaborators and Investigators

• Sponsor: Seoul National University Hospital
• Investigators: Study Director: Yunseok Jeon, M.D, Seoul National University Hospital

Study record dates

Study Major Dates

• Study Start: August 1, 2009
• Primary Completion (ACTUAL): September 1, 2009
• Study Completion (ACTUAL): September 1, 2009

Study Registration Dates

• First Submitted: June 8, 2010
• First Submitted That Met QC Criteria: June 14, 2010
• First Posted (ESTIMATE): June 15, 2010

Study Record Updates

• Last Update Posted (ESTIMATE): June 15, 2010
• Last Update Submitted That Met QC Criteria: June 14, 2010
• Last Verified: June 1, 2010

More Information

Terms related to this study

• Keywords: Passive leg raising; FloTrac/Vigileo; Anesthesia hypotension
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Disease; Heart Diseases; Coronary Artery Disease; Myocardial Ischemia; Hypotension; Heart Valve Diseases
• Other Study ID Numbers: H-0809-037-256