BY AHMAD YOUNES PROFESSOR OF THORACIC MEDICINE Mansoura Faculty of Medicine

1. BYAHMAD YOUNESPROFESSOR OF THORACIC MEDICINE Mansoura Faculty of Medicine Six Minutes Walking Test BYAHMAD YOUNESPROFESSOR OF THORACIC MEDICINE Mansoura Faculty of Medicine

2. Purpose of the six minute walk test 1-Assess exercise tolerance in patients with chronic respiratory disease and heart failure. 2-Measuring the response to medical interventions in patients with moderate to severe heart or lung disease. 3- Used as a one-time measure of functional status of patients, as well as a predictor of morbidity and mortality • It is important to standardise procedures, describe required preparation, and outline safety measures. • This document is based on the ATS guidelines 2002.

3. INDICATIONS FOR THE SIX-MINUTE WALK TEST Pretreatment and posttreatment comparisons • Lung transplantation • Lung resection • Lung volume reduction surgery • Pulmonary rehabilitation • COPD • Pulmonary hypertension • Heart failure Functional status (single measurement) • COPD , Cystic fibrosis ,Heart failure ,Peripheral vascular disease ,Fibromyalgia ,Older patients Predictor of morbidity and mortality • Heart failure ,COPD ,Primary pulmonary hypertension

4. Limitation of Six Minutes Walking Test • The 6MWT does not determine peak oxygen uptake, diagnose the cause of dyspnea on exertion, or evaluate the causes or mechanisms of exercise limitation . • The information provided by a 6MWT should be considered complementary to cardiopulmonary exercise testing, not a replacement for it. • Formal cardiopulmonary exercise testing provides a global assessment of the exercise response, an objective determination of functional capacity and impairment, determination of the appropriate intensity needed to perform prolonged exercise, quantification of factors limiting exercise, and a definition of the underlying pathophysiologic mechanisms such as the contribution of different organ systems involved in exercise.

6. Limitation of Six Minutes Walking Test • A significant correlation (r 0.73) between 6MWD and peak oxygen uptake has been reported for patients with end-stage lung diseases • Six MWD correlates better with formal measures of quality of life . • Changes in 6MWD after therapeutic interventions correlate with subjective improvement in dyspnea . • The reproducibility of the 6MWD (with a coefficient of variation of approximately 8%) appears to be better than the reproducibility of FEV1 in patients with COPD. • Questionnaire indices of functional status have a larger short-term variability (22–33%) than does the 6MWD

7. Shuttle-walking test • It is similar to the 6MWT, but it uses an audio signal from a tape cassette to direct the walking pace of the patient back and forth on a 10-m course . The walking speed is increased every minute, and the test ends when the patient cannot reach the turn around point within the required time. • The exercise performed is similar to a symptom limited, maximal, incremental treadmill test. • An advantage of the shuttle walking test is that it has a better correlation with peak oxygen uptake than the 6MWD . • Disadvantages include less validation, less widespread use, and more potential for cardiovascular problems.

8. Equipment  Stopwatch or countdown timer • Lap counter • Two small cones to mark the turnaround points • A chair that can be easily moved along the walking course • Clipboard with a 6MWT proforma and a pen • BORG and fatigue Scales • Automated blood pressure machine • Pulse oximeter • Trundle wheel, or pre-measured marks along the track/corridor • Access to oxygen and telephone in case of an emergency

12. Precautions Absolute contraindications for the 6MWT include: • unstable angina • myocardial infarction during the previous month. Relative contraindications for the 6MWT include: • resting heart rate of >120 • a systolic blood pressure of >180 mm Hg • diastolic blood pressure of >100 mm Hg • Stable exertional angina is not an absolute contraindication for a 6MWT, but patients with these symptoms should perform the test after using their antiangina medication, and rescue nitrate medication should be readily available.

13. Safety Issues 1. Testing should be performed in a location where a rapid, appropriate response to an emergency is possible. 2. Supplies that must be available include oxygen, sublingual nitroglycerine, aspirin, and Salbutamol (metered dose inhaler or nebuliser). A telephone or other means should be in place to enable a call for help. 3. The technician should be certified in cardiopulmonary resuscitation with a minimum of Basic Life Support. Physicians are not required to be present during all tests. 5. If a patient is on chronic oxygen therapy, oxygen should be given at their standard rate or as directed by a physician or a protocol.

14. Stop the Test in the Event of Any of the Following • Chest pain suspicious for angina. • Mental confusion or lack of coordination/staggering. • Evolving light-headedness. • Intolerable dyspnoea. • Leg cramps or extreme leg muscle fatigue. • Excessive sweating • Persistent SpO2 < 85% (if this is unusual for the subject) • Pale or ashen appearance that occurs during the test Physicians are not required to be present during all tests. Technicians must be trained to recognise these problems and the appropriate responses.

15. Preparation Establishment of a Walking Track • The track may be a continuous track (oval or rectangular) or a point-to-point track. • In the case of a point-to-point track, the walking course must be 30m in length, with the turnaround points marked with a cone. A starting line, which marks the beginning and end of each lap, should be marked on the floor using brightly coloured tape, unless one of the cones marks the start. • The track should be flat, with minimal obstacles. • The track could be marked in 1-metre or 3-metre increments to assist in calculation of partial lap completion at the end of the test.

16. Preparation • Note:If you do not have access to at least a 25m track, make sure you use the same track for all tests and be aware that the distance walked may be less due to the patient having to slow down and turn more often in the six minutes. • The walking track should be in an area with a maintained comfortable ambient temperature and humidity.

17. Patient Preparation  Take into account any precautions or contraindications prior to performing the walk test • Instruct the subject to dress comfortably and wear appropriate footwear • The subject should be advised to avoid eating a heavy meal for two hours before the test • Any prescribed inhaled bronchodilator medication should be taken within one hour of testing • The subject should rest for at least 15 minutes before beginning the 6MWT • A ‘warm up’ should not be performed.

18. Quality Assurance • Technicians who perform 6MWTs should be trained using the standard protocol and then supervised for several tests before performing them alone. • Only the standardised phrases for encouragement must be used during the test. Encouragement significantly increases the distance walked. • If oxygen supplementation is needed during the walks and serial tests are planned, then during all walks by that subject oxygen should be delivered in the same way with the same flow.If O2 flow must be increased during subsequent visits due to worsening gas exchange, this should be noted on the worksheet and considered during interpretation of the change noted in 6MWD.

19. Quality Assurance • Measurements of pulse and SpO2 should be made after waiting at least 10 minutes after any change in oxygen delivery. The type of oxygen delivery device should also be noted on the report. • Technicians should avoid walking behind the subject with the oxygen source, however if the subject is not able to control/carry/manage their own oxygen cylinder, the technician should try to walk slightly behind the subject to avoid setting the walking pace. It should be clearly documented how the technician has assisted with the transport of the oxygen, so any subsequent walk tests with the same subject can be performed in the same manner.

20. Quality Assurance • The type of medication, dose, and number of hours taken before the test should be noted. Significant improvement in the distance walked, or the dyspnoea scale, after administration of bronchodilators has been demonstrated in patients with COPD.

21. Procedure  The 6MWT must initially be performed on two occasions to account for a learning effect. The best distance walked in metres is recorded. • If the two tests are performed on the same day, at least 1 hour rest should be allowed between tests. Some individuals may require tests to be performed on separate days, preferably less than one week apart. • Set the lap counter to zero, and the timer to 6 minutes • After the subject has been at rest for 15 minutes, obtain and record measurements of blood pressure, heart rate, oxygen saturation and Borg dyspnoea and fatigue scores. 3) Direct the subject to the ‘start line’ of the walking track.

22. Procedure 4) Describe the walking track to the subject, and then demonstrate by walking one lap yourself. Walk and pivot around a cone briskly (if applicable). 5) Give the patient the following 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 will probably get out of breath or become exhausted. You are permitted to slow down, to stop, and to rest as necessary. You may lean against the wall while resting, but resume walking as soon as you are able. You will be walking back and forth around the cones. You should pivot briskly around the cones and continue back the other way without hesitation. Now I'm going to show you. Please watch the way I turn without hesitation."

23. Procedure • Demonstrate by walking one lap yourself. Walk and pivot around a cone briskly."Are you ready to do that? I am going to use this counter to keep track of the number of laps you complete. I will click it each time you turn around at this starting line. Remember that the object is to walk AS FAR AS POSSIBLE for 6 minutes, but don't run or jog. Start now, or whenever you are ready." 6) Start the timer when the patient begins to walk 7) Monitor the subject for any untoward signs and symptoms throughout the duration of the test

24. Procedure 8) Do not talk to anyone during the walk. Use an even tone of voice when using the standard phrases of encouragement. • Watch the patient. Do not get distracted and lose count of the laps. Ensure you keep count of the number of lengths or laps as the subject completes them, throughout the duration of the test. • Each time the participant returns to the starting line, click the lap counter once (or mark the lap on the worksheet). Let the participant see you do it – exaggerate the motion if necessary.

25. Procedure 9) Use the following standard encouragements during the test, using an even tone of voice: • At minute one: “You are doing well. You have five minutes to go.” • At minute two: “Keep up the good work. You have four minutes to go.” • At minute three: “You are doing well. You are halfway done.” • At minute four: “Keep up the good work. You have only two minutes left” • At minute five: “You are doing well. You have only one minute to go.”

26. Procedure 10) If the subject stops during the six minutes: • Do NOT stop the timer • Allow the subject to sit in a chair if they wish. • Measure and record the oxygen saturations and heart rate. • Ask patient why they stopped, and record the reason. • Record the time the subject stopped (but keep the stop watch running). • If the patient stops, give the following instruction “You can lean against the wall if you would like; then continue walking whenever you feel able.” • If the patient refuses to continue (or you decide that they should not continue), discontinue the walk, and note on the worksheet the distance, the time stopped, and the reason for stopping prematurely.

27. Procedure 11) When the timer is 15 seconds from completion, say: "In a moment I'm going to tell you to stop. When I do, just stop right where you are and I will come to you". 12) When the time reaches exactly 6 minutes, say: "Stop!". Consider taking a chair over to the subject if they look exhausted. Mark the spot where they stopped by placing a marker on the floor. Allow the subject to sit down or, if the subject prefers, allow to them to stand. Note:The measurements taken before and after the test should be taken with the subject in the same position. 14) Immediately record oxygen saturation, heart rate, blood pressure, Borg dyspnoea and fatigue rating .

28. Procedure 15) Total up the number of lengths/laps walked, and measure the excess distance with a tape measure /marks along track or corridor. Tally up the total distance walked by the subject, rounded to the nearest metre, and record on the proforma. 16) Congratulate the patient on good effort and offer a drink of water. 17) The subject should remain in a clinical area for at least 15 minutes following an uncomplicated test, or be allowed to rest for at least 30 minutes if performing the second walk test on the same day.

29. INTERPRETATION • It is not known whether it is best for clinical purposes to express change in 6MWD as : 1) an absolute value, 2) a percentage change, or 3) a change in the percentage of predicted value. • we recommend that change in 6MWD be expressed as an absolute value (e.g., the patient walked 50 m farther). • In stable severe COPD and older patients with heart failure , the smallest difference in 6MWD that was associated with a noticeable clinical difference in the patients’ perception of exercise performance was a mean of 54 m and 43 m respectively.

30. INTERPRETATION • The median 6MWD was approximately 580 m for healthy men and 500 m for healthy women. • Differences in the population sampled,type and frequency of encouragement, corridor length,and number of practice tests may account for reported differences in mean 6MWD in healthy persons. • Age, height, weight,and sex independently affect the 6MWD in healthy adults;therefore, these factors should be taken into consideration when interpreting the results of single measurements made to determine functional status.

31. 6 MWD SOURCES OF VARIABILITY Factors reducing the 6MWD • Shorter height • Older age • Higher body weight • Female sex • Impaired cognition • A shorter corridor (more turns) • Pulmonary disease (COPD, asthma, cystic fibrosis, interstitial lung disease) • Cardiovascular disease (angina, MI, CHF, stroke, TIA, PVD, AAI) • Musculoskeletal disorders (arthritis, ankle, knee, or hip injuries, muscle wasting, etc.)

32. 6 MWD SOURCES OF VARIABILITY Factors increasing the 6MWD • Taller height (longer legs) • Male sex • High motivation • A patient who has previously performed the test • Medication for a disabling disease taken just before the test • Oxygen supplementation in patients with exercise-induced hypoxemia

34. Conclusions • The 6MWT is a useful measure of functional capacitytargeted at people with at least moderately severe impairment. • The test has been widely used for preoperative and postoperative evaluation and for measuring the response to therapeutic interventions for pulmonary and cardiac. • A low 6MWD is nonspecific and nondiagnostic. • When the 6MWD is reduced,a thorough search for the cause of the impairment is warranted. • The following tests may then be helpful: pulmonary function, cardiac function, muscle strength, nutritional status, orthopedic function, and cognitive function.

36. MEDICAL INTERNATIONAL RESEARCH • SPIRODOC spirometer + oximeter from MEDICAL INTERNATIONAL RESEARCH (MIR) calculates a series of parameters relating to human respiratory function . • SPIRODOC has been designed for use in the doctor’s office, in a hospital or directly by the patient to continuously monitor her/his physical conditions during routine daily activities. • An analysis of the results of a spirometry test is not by itself sufficient to make a correct diagnosis of the patient’s clinical condition. A detailed clinical history of the patient is also required together with the results of any other test(s) suggested by a doctor. • When used as a pulse oximeter the SPIRODOC has limited alarms, therefore the device requires frequent display observation of SpO2 and pulse rate.

37. Parameters for the oximetry test

40. Parameters requested for six minute walk test analysis

41. ETIOLOGY

42. Acoustic signals • “Beep” with frequency of the cardiac pulse • “Beep” with special alarm frequency in the case of either %SpO2 or cardiac pulse going outside of the programmed levels of alarm • “Beep” with special alarm frequency during oximetry measurement in the case of a low battery level. • If the patient’s finger is not inserted correctly or the connecter is not properly attached there will be an intermittent beeping sound for 10 seconds • If the test has been interrupted due to unexpected event an intermittent beeping will be heard for 5 seconds when the device is switched on again • The specifications for both the oximetry and for the cardiac pulse are the same regardless of which of the above mentioned oximetry sensors is used.

43. Display • The device does not have a keyboard. • The touch screen type display allows access to all functions by simply touching the display. • The controls on the touch screen change dynamically based on the functions performed. • To access a specific function touch the corresponding icon on the display.

44. Switching on and off the SPIRODOC • To turn on the SPIRODOC press and release the power key placed in the middle on the side of the device. • If the spirodoc is connected to USB , power supply is not possible to switched OFF. • Upon turning on the device the very first image displayed refers to the manufacturer including the date and time setting. • Without touching the display after a few seconds the device automatically moves on to the main screen • By touching the icon , different information is visualized according to which mode; Doctor or Patient the device has been set to

45. Doctor Mode The information displayed are: • Spirometry parameter setting • Oximetry parameter setting • Spirometry and oximetry tests in memory • Free memory available Patient Mode The information displayed are: • Number of activated symptoms • Number of activated questions • Spirometry and oximetry tests in memory • Free memory available

46. To turn off SPIRODOC • press the key placed on top and subsequently touch OK on the bottom right side of the screen. • It is possible to turn off the device by keeping the top key pressed. • The message on the right side is shown after pressing the key on top It serves as a guide to follow the procedure properly.

47. WARNING • When the device is turned on after approximately 1 minute of disuse the display enters energy saving mode thereby automatically lowering the display contrast level. • If the device remains in disuse for approximately 5 minutes and is not connected to a PC or battery charger; the device will emit an acoustic warning signal and turn off. • When the device is turned on the battery charge level is shown with the symbol: This image indicates that the battery pack is fully charged(6 indicators). A drop of the battery pack charge is displayed with a reduction of the indicators .

48. Main screen

49. Symbols and Icons

50. Symbols and Icons