What is the protocol for administering the six minute walk test (6MWT) to patients with chronic diseases such as heart failure, chronic obstructive pulmonary disease (COPD), and pulmonary hypertension?

Six-Minute Walk Test Protocol for Patients with Chronic Diseases

The six-minute walk test (6MWT) should be performed in a 30-meter straight, flat corridor with standardized instructions and encouragement to accurately assess functional exercise capacity in patients with chronic heart failure, COPD, and pulmonary hypertension. 1

Test Environment and Safety Requirements

• Testing must be conducted in a location where emergency response is possible, with a crash cart nearby as determined by the supervising physician 1
• Required supplies include oxygen, sublingual nitroglycerin, aspirin, albuterol, and a telephone for emergency calls 1
• The technician must be certified in cardiopulmonary resuscitation (minimum Basic Life Support) 1
• The test should be performed indoors in a 30-meter long corridor with minimal traffic, marked every 3 meters 1
• Turnaround points should be marked with cones, and the starting line marked with brightly colored tape 1

Required Equipment

• Countdown timer or stopwatch 1
• Mechanical lap counter 1
• Two small cones to mark turnaround points 1
• A movable chair for the walking course 1
• Worksheets on a clipboard 1
• Oxygen source 1
• Sphygmomanometer 1
• Automated electronic defibrillator 1

Patient Preparation

• Patients should wear comfortable clothing and appropriate walking shoes 1
• Patients should use their usual walking aids (cane, walker) during the test 1
• Continue the patient's usual medical regimen 1
• A light meal is acceptable before morning or early afternoon tests 1
• Patients should avoid vigorous exercise within 2 hours of the test 1
• For repeat testing, perform at the same time of day to minimize variability 1

Contraindications

• Absolute contraindications: unstable angina or myocardial infarction during the previous month 1
• Relative contraindications: resting heart rate >120 bpm, systolic blood pressure >180 mmHg, or diastolic blood pressure >100 mmHg 1
• Patients with stable exertional angina should take their antiangina medication before the test, with rescue nitrates readily available 1

Test Procedure

1. Measure baseline heart rate, blood pressure, oxygen saturation, and Borg dyspnea scale 1

2. Set the timer for 6 minutes 1

3. Position the patient at the starting line 1

4. Use standardized instructions: "The object of this test is to walk as far as possible for 6 minutes. You will walk back and forth in this hallway. Six minutes is a long time to walk, so you will be exerting yourself. You are permitted to slow down, stop, and rest as necessary, but resume walking as soon as you are able." 1

5. Start the timer when the patient begins walking 1

6. Use only standardized encouragement phrases at each minute: 1

   • First minute: "You are doing well. You have 5 minutes to go."
   • Second minute: "Keep up the good work. You have 4 minutes to go."
   • Third minute: "You are doing well. You're halfway done."
   • Fourth minute: "Keep up the good work. You have only 2 minutes left."
   • Fifth minute: "You are doing well. You have only 1 minute to go."
   • Sixth minute: "Please stop where you are."

7. If the patient stops during the test, say: "You can lean against the wall if you would like; then continue walking whenever you feel able." Do not stop the timer. 1

Reasons to Immediately Stop the Test

• Chest pain 1
• Intolerable dyspnea 1
• Leg cramps 1
• Staggering 1
• Diaphoresis 1
• Pale or ashen appearance 1

Post-Test Assessment

• Record the total distance walked in meters 1
• Measure post-walk heart rate, blood pressure, oxygen saturation, and Borg dyspnea scale 1
• Ask the patient what, if anything, prevented them from walking farther 1
• Calculate the total distance walked by counting completed laps and adding any partial lap distance 1

Special Considerations

• Practice tests: Consider performing a practice test in research settings. If done, wait at least 1 hour before the second test and report the highest 6MWD as baseline 1
• Supplemental oxygen: If a patient requires oxygen, deliver it in the same way with the same flow for all serial tests. Note the type of oxygen delivery device on the report 1
• Medications: Document type, dose, and timing of medications taken before the test 1

Interpretation of Results

• A 6MWD less than 350 meters is associated with increased mortality in COPD, chronic heart failure, and pulmonary arterial hypertension 2
• A change in walking distance greater than 50 meters is generally considered clinically significant 2
• Consider factors affecting performance: height, age, weight, sex, cognitive status, corridor length, and comorbidities 1

Common Pitfalls to Avoid

• Using a treadmill instead of a corridor (reduces 6MWD by approximately 14%) 1
• Inconsistent encouragement between tests (standardized phrases are essential) 1
• Failure to account for practice effects (performance typically plateaus after two tests within a week) 1
• Inadequate documentation of oxygen supplementation or medication use 1
• Technician variability (proper training is essential as technician differences can affect results by approximately 7%) 1

The 6MWT provides valuable information about functional capacity that correlates well with quality of life measures and can predict morbidity and mortality in patients with chronic cardiopulmonary diseases 1, 2.