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CARDIOPULMONARY EXERCISE
TESTING PROTOCOLS AND THE NORMAL
PHYSIOLOGIC RESPONSES
Carl D. Mottram, RRT RPFT FAARCAssociate Professor of Medicine – EmeritusMayo Clinic College of MedicinePresident PFWConsulting LLC
MISSION IMPOSSIBLE
CARDIOPULMONARY EXERCISE TESTING
Oxygen consumption (VO2max)
Index of cardiopulmonary fitness (gold standard)
Cardiovascular response
Ventilatory limitation and breathing strategies
Gas Exchange
Metabolic calculations and derivatives
Mottram CD. Manual of Pulmonary
Function Testing 11th Ed 2017
EXERCISE TESTING GUIDELINES
AHA Recommendations for Clinical Exercise Testing Circulation. 2009;119: 3144-3161
Circulation 2010, 120 191-225
Circulation. 2013;128:873-934
ACC/AHA Guidelines for Exercise Testing J Am Coll Cardiol 1997;30:260-315
Updated in 2002 (www.americanheart.org)
ATS/ACCP Statement on Cardiopulmonary Exercise Testing Am J Respir Crit Care Med Vol 167. pp 211–277,
2003
EXERCISE TESTING GUIDELINES
Clinical Stress Testing in the Pediatric Age Group - AHA Council on Cardiovascular Disease in the Young, Committee on Atherosclerosis, Hypertension, and Obesity in Youth. (Circulation. 113(15):1905-20, 2006 Apr 18)
ACC-AHA Clinical Competency statement on Stress testing (Circulation Oct 2000, Volume 102, Issue 14)
ATS Pulmonary Function Laboratory Management and Procedure Manual. 3rd Edition 2016
www. thoracic.org
CLINICAL INDICATIONS
Evaluate specific symptoms or signs that may be aggravated or induced by exercise
Assess or identify abnormal response to exercise in subjects with disease
Evaluate prognosis (i.e. surgical risk)
Assess the effectiveness of medical or surgical treatments
Establish baseline for rehabilitation
•Adapted from AHA 2013 Guideline
EXERCISE TESTING PROTOCOLS
EQUIPMENT
Ergometer Treadmill
Cycle ergometer
Other forms of exercise (arm ergometer, step exercise or timed walking)
Exhaled gas analysis system
ECG monitor and blood pressure
Pulse Oximetry or ABG’s
EXERCISE TESTING PROTOCOLS
ERGOMETERS
EXERCISE TESTING PROTOCOLS
TREADMILL
Advantages
Natural form of
exercise
Ease of
calibration
Higher VO2 max
Disadvantages
Risk of accidents and patient fear/anxiety
More motion artifact
Difficult to obtain blood samples
Difficult to quantify work performed
EXERCISE TESTING PROTOCOL
CYCLE ERGOMETER
Advantages
Safer
Ease of monitoring (e.g. reduced ECG & B/P noise)
Quantification of work
Ease of obtaining blood samples
Disadvantages
Difficult to calibrate
Leg fatigue and unfamiliarity with cycle exercise
Lower VO2 max
EXERCISE TESTING PROTOCOL
STEADY STATE INCREMENTAL
Typically 3-minute stages, but can be longer
Large increments in work
Warm-up
EXERCISE TESTING PROTOCOL
INCREMENTAL STEP
1-minute increments after a warm-up period
Variable increases in the workload increments
EXERCISE TESTING PROTOCOL
RAMP
Continuous increase in work throughout exercise
Ramp
EXERCISE TESTING PROTOCOLS
TREADMILL
Bruce Protocol “Fast”- large increases in workload
3 minute stages
295 subjects (138 male, 157 female), age 29-73
Reproducibility of VO2max, SEE 3.2%
Metabolic equivalent (MET)
Exercise time (mins.) Mayo study results
Men:16.3 - 0.12(age) Females:13.0 - 0.10 (age)
EXERCISE TESTING PROTOCOLS
TREADMILL
Bruce Treadmill Test in Children327 children ages 4-15
Predicted values
Exercise time, HR, VO2
Cumming GR, et al Amer J of Cardiology (41) pg.69-75 1978
Naughton & Balke
“slow”- smaller increases
constant speed, increasing grade
Modified Protocols
EXERCISE TESTING PROTOCOLS
TREADMILL
Treadmill protocol that uses a linear increase in walking speed coupled with a curvilinear increase in treadmill grade.
Med. Sci. Sports Exerc., Vol. 35, No.
9, pp. 1596–1603, 2003.
EXERCISE TESTING PROTOCOLS
CYCLE ERGOMETER
Unit of measure - watt, kpm/m
Incremental or ramp protocol
Target maximum time of test 8-12 minutes
Determining maximal target workload
EXERCISE TESTING PROTOCOLS
CYCLE ERGOMETER
To determine predicted maximal power
output
VO2 = VO2unl + (10 – T ) X 10 X S
T = time constant
S = slope of the rate of increase
(VO2 max predicted - VO2 rest)/10 = predicted max. power output (power in watts)
EXERCISE TESTING PROTOCOLS
CYCLE ERGOMETER
Example: Predicted VO2 = 2300 mls
Rest VO2 = 300 mls
2300-300/10 = 200 watts predicted max
10 minutes = 200/10 = 20 watt increment or ramp
Reduce the predicted max workload for subjects with reduced exercise tolerance
Increase the estimated maximal power output for very fit subjects
EXERCISE TESTING PROTOCOLS
CYCLE ERGOMETER
Suspected ventilatory limited subjects
COPD, Restrictive disease
MVV < 40L/min
5 watt incremental or ramp
MVV > 40 < 80
10 watt incremental or ramp
CPET – NORMAL PHYSIOLOGIC
RESPONSE
Cardiovascular
response
Ventilatory response
Gas exchange
VO2 response
Anaerobic/Ventilatory
ThresholdMottram CD. Manual of Pulmonary
Function Testing 11th Ed 2017
CARDIOPULMONARY EXERCISE TESTING:
CARDIAC RESPONSE
ECG/EKG analysis in exercise testing
Arrhythmia
ST segments
Drug effects
Other
WPW, BBB
CARDIOVASCULAR RESPONSE
Maximum Heart Rate
210 - .65(age) or
220 - age
>85-90% HR pred.
Cardiac Output
Stroke volume
Weber KT, Janicke JS Cardiopulmonary Exercise Testing, Saunders 1986
CARDIOVASCULAR RESPONSE
Oxygen Pulse
Fick principle
Cardiac Output = VO2/A-V difference
HR x stroke volume = VO2/A-V difference
O2 Pulse = VO2/HR = SV x A-V difference
O2 Pulse = Stroke Volume?
CARDIOVASCULAR RESPONSE –
BLOOD PRESSURE
Adults
Normal : 160-220/50-90
HypertensionSystolic >225 mmHg
Diastolic >90 mmHg
Daida H. Mayo Clinic Proceedings (71) 445-452, 1996
Pediatric
Maximal exercise systolic pressure is positively related to Ht, workload and resting systolic pressure
James F. Circulation 1980; 61; 902-912
VENTILATORY CAPACITY
Ventilatory Capacity (VEcap)
Maximal Voluntary Ventilation (MVV)
FEV1 x 40
VEmax = 60-80% of VEcap
Flow limitation
FV loops during exercise
0%
2%
4%
6%
8%
10%
12%
14%
16%
Freq
uenc
y
20 30 40 50 60 70 80
MVV/FEV1
Restr MildOb Sev Ob
VENTILATORY CAPACITY
Ventilatory Capacity Pediatric
0%
10%
20%
30%
40%
20 30 40 50 60 70 80
MVV/FEV1
Fre
qu
en
cy
5-10 y.o. n=1457 10-15 y.o. n=3319
VENTILATORY CAPACITY
231 subjects (111 male, 120 female)
Mean VEmax as a fraction of MVV 0.61
(range 0.28 -1.02)
Blackie SP, Fairbarn MS, et al:
Normal values and ranges for ventilation and
breathing pattern at maximal exercise. Chest
100:136, 1991
VENTILATORY CAPACITY
MVV = 10-12 second maneuver that is extrapolated to 1 minute
Freedman S. et. al Respiration Physiology (8) 230-244, 1970
VENTILATORY CAPACITY
Ventilatory or Breathing reserve:
Ventilatory capacity -VEmax
20-30 liters (10-15 L minimum)
20-40%
“Ventilatory limitation”
Oxygen Consumption, l/min
0.00.51.01.52.02.53.03.54.0
Minute Ven
tilation, l/m
in0
20
40
60
80
100
120
140
160
180
200
VE Reserve.
VE Capacity.
VE Threshold.
Mottram CD. Manual of Pulmonary Function Testing 2017
BREATHING KINETICS
Jones, N. Clinical Exercise Testing,
Saunders, 1997
BREATHING KINETICS
Blackie SP, Fairbarn MS, McElvaney NG, et al: Chest 100:136, 1991
BREATHING KINETICS
Jones, N. Clinical Exercise Testing,
Saunders, 1997
BREATHING KINETICS:
FLOW-VOLUME LOOP ANALYSIS
Quantify flow
limitation
Johnson BD. Weisman IM. Zeballos RJ.
Beck KC. Emerging concepts in the
evaluation of ventilatory limitation during
exercise: the exercise tidal flow- volume
loop. Chest. 116(2):488-503, 1999 Aug
Volume, l
0 1 2 3 4 5 6Flow
, l/sec
-10
-8
-6
-4
-2
0
2
4
6
8
10
12
ext FVL
Rest FVL
MFVL
Rest IC
ext IC
Vol of FL
BREATHING KINETICS:
FLOW-VOLUME LOOP ANALYSIS
Quantification of flow limitation
Flow/volume characteristics
Fixed, variable intra/extra-thoracic
obstruction
Breathing kinetics
Location of tidal breathing on the
absolute lung volume scale
Flow Volume Loop Dynamic ProfilesF
low
(L
/sec
)
Normal
10
8
6
4
2
0
2
4
6
8Severe COPD
Rest
1 2 3 4 5 1 2 3 4 5
Rest Rest
Ex
Ex
Exercise
Mottram CD, Manual of Pulmonary Function Testing 2017
BREATHING KINETICS: FVL
ANALYSIS
Normal
BREATHING KINETICS: FVL
ANALYSIS
Flow limitation
BREATHING KINETICS: FVL
ANALYSIS
Inappropriate Shift
BREATHING KINETICS: FVL
ANALYSIS
Vocal Cord Dysfunction
BREATHING KINETICS: FVL
ANALYSIS
Pseudo – Asthma “type 2”
GAS EXCHANGE
PULSE OXIMETRY
Site and artifact management
Multiple sensors
Be careful!!!
GAS EXCHANGE - ARTERIAL BLOOD
GASES
CLSI H11-A4 Procedures for the Collection of Arterial Blood Specimens
Arterial CatheterRadial, brachial
Frequency is up to the institutional practice
lactate
Rest and end-exercise single stickWithin 30 seconds
GAS EXCHANGE
PaO2 is relatively
stable with the (A-
a) gradient < 20
PaO2 may fall in
highly trained subjects
Example end-exercise ABG:
110/28/7.29
GAS EXCHANGE
VD/VT
Rest: 30 - 40%, Maximal exercise: near 20%
Elderly normals: Values higher, but kinetics same
METABOLIC RESPONSE
Oxygen uptake (VO2) is determined by
cellular demand and the subject’s
maximal rate of O2 transport
VO2 – work-rate relationship
8.5 – 11 ml/min/watt
Predicted VO2max/peak influenced
by height, age, and sex
METABOLIC RESPONSE
Fick Equation
Reductions in
VO2max can be
from a single entity
or multifactorial
Oded Bar-Or Pediatric Exercise
Medicine Human Kinetics 2004
Determining Anaerobic threshold or ventilatory threshold
Change in R
Ventilatory equivalents
V-slope
Metabolic ResponseAnaerobic Threshold/Ventilatory Threshold
Mottram CD. Manual of Pulmonary
Function Testing 2017
METABOLIC RESPONSE
ANAEROBIC THRESHOLD/VENTILATORY
THRESHOLD
Lactate kineticsKanaley JA. Mottram CD. et. al
Fatty acid kinetic responses to
running above or below lactate threshold. Journal of Applied
Physiology. 79(2):439-47, 1995
Aug.
End-exercise > 7 mMol/L
PATIENT TESTING – SYMPTOM SCALES
Ratings of Perceived Exertion
Borg scale (Original and Modified)
0-4 Visual analog scales
Chest pain, chest tightness, asthma symptoms, lightheadedness
PATIENT TESTING: EARLY TERMINATION
Angina > 3 (1-4 scale)
> 2 mm horizontal or downsloping ST segment depression or elevation
Ventricular arrhythmia: VT, sustained PSVT, 3rd degree heart block
Systolic or diastolic B/P > 250 and 120 mmHg respectively, or a >20 mm decline of systolic B/P
Failure of monitoring system
“If it were only that simple!!”
Questions?