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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?