Exercise Testing in Kids Flashcards
Cardiac output for healthy children increases ___ above resting levels
3-4 times
Most of the increase is due to heart rate, only 20-25% is due to stroke volume
Boys HR and SV
Boys: heart rate is lower and stroke volume slightly higher
No gender differences in cardiac output or in arterial-venous O2 difference
8 y/o vs 18 y/o HR
Submaximal HR in children decline with age
HR can be 30-40 beats higher in an 8 y/o than in an 18 y/o performing the same task
Due to lower SV at younger age
Normal Responses to Exercise
Heart Rate: max heart rate of 200 bpm (190-210)
The formula of (220-age) does not really work well until late teens or early twenties
BP: BSA 1.25 m2 = 140 mmHg
BSA 1.75 m2 = 170 mmHg
SBP > 220 mmHg is of increased concern
DBP should only vary ± 6-10 mmHg
Abnormal SBP: failure to increase appropriately or decreases with increasing exercise intensity
Abnormal DBP: increasing more than 20 mmHg
Bruce Protocol
Bruce is most traditional and has largest normative data set
Disadvantages: steep grades for young patients, large MET increases between stages, long stage durations
Uses 3 minute stages, with grade starting at 10%. The grade increases by 2% with each stage increase, along with a slight increase in speed.
Balke Protocol
Several variations exist
Often will see “modified Balke” protocols
Speed is usually kept constant at 3.0 or 3.5 mph
Grade is increased 2% every minute or 2.5% every 2 minutes
Good for children with perceived low aerobic capacity
Tilt Table Testing
Indications for tilt-table
Syncope or presyncope
Persistent dizziness
Tachycardia
Extreme fatigue
2 Modes:
Passive: 20 minutes supine followed by 20 minutes at 80° head up tilt
Active: exercise test followed by 20 minutes at 80° head up tilt
Parameters monitored:
Heart rate & rhythm, blood pressure, and oxygen saturation
Passive Tilt Testing
Used to evaluate patients whose symptoms occur with change of position, standing or other non-exercise related situations
Symptoms most common in slender, rapidly growing adolescents
Females more predominate
Patients frequently skip breakfast and have very little fluid intake to start the day
Overall daily fluid intake is also very limited
Exercise Tilt Testing
Used to evaluate patients with symptoms which occur during and after exercise, or only after exercise
Often seen in competitive athletes and normally active teenagers
Typically seen in distance runner
Males more predominant?
Positive Test Findings (tilt Test)
Loss of consciousness
Symptomatic hypotension
Symptomatic bradycardia/asystole
Persistent tachycardia without corresponding decrease in blood pressure
Hypotension with inappropriate heart rate response
Cardiac Causes of Acute Onset Chest Pain
Pericarditis
Trauma
Hemopericardium
Arrhythmias
Noncardiac Causes of Acute Onset Chest Pain and Shortness of Breath
Pulmonary Pneumothorax Pneumonia Pleurodynia Esophageal Acute esophagitis Foreign body Noncardiac/Nonorganic Idiopathic Psychogenic Cardiac conditions associated with pain Myocardial ischemia Coronary artery anomalies Pericarditis Mitral Valve Prolapse Other Causes Esophagitis Costochondritis Asthma Sickle Cell Disease Vocal Cord Dysfunction
Exercise-Induced Asthma
EIA symptoms
Coughing
Wheezing
Chest tightness
Shortness of breath
Symptoms frequently begin 5-20 minutes after exercise begins
EIA may occur more easily on cold, dry days than on warm, humid days
Most children with EIA should be able to exercise vigorously with proper diagnosis and treatment
FEV1
Primary value used to determine bronchodilator response
An increase of 200 ml or 12% is considered a positive response
FVC
An increase of 10% or more is considered a positive response
FEF25-75%
An increase of >20% is considered a positive response
Vocal Cord Dysfunction
Occurs most frequently in active adolescents and young adults
May mimic exercise-induced asthma
Occurs more in females than males
Symptoms do not respond to common asthma medications
Does not appear to be sport specific
May occur as a co-morbid condition with asthma
Common Triggers for Vocal Cord Dysfunction and Asthma
Bronchitis or pneumonia Fumes and odors Upper Respiratory Infections Cigarette or other sources of smoke Post-nasal drip Emotions Singing Exercise
Symptoms of Vocal Cord Dysfunction
Stridor Chest or throat tightness “Can’t get air in” or “Something is stuck in my throat” Abrupt onset and resolution of symptoms Chronic cough and hoarseness Tingling in the arms and legs Feeling faint Shortness of breath and breathing difficulty
Gastroesophageal Reflux Disease(GERD)
In children with both asthma and GERD, treating GERD can improve asthma exacerbations
About 2/3 of patients with asthma have underlying reflux and GERD has been implicated in provoking asthma
While the connections between asthma and GERD remain unclear, researchers have reported that anti-reflux medications maybe help asthma symptoms
Purpose of Spirometry
To classify lung function into 4 categories Normal Obstructive Restrictive Combined obstructive/restrictive
FVC define
FVC
Forced Vital Capacity
The maximum volume of air that can be forcefully exhaled after the deepest possible inspiration
Decreased with restrictive disease
Normal or decreased with obstruction (depending on severity)
FEV1 define
Forced Expiratory Volume in 1 second
Indicator of large airway obstruction
Normal value should be >80% of predicted
BIG INDICATOR FOR ASTHMA
FEV1/FVC define
Ratio used to classify lung function
Best predictor of obstruction
If below 80% of predicted
Think obstruction
FEF25-75% define
Forced Expiratory Flow or Midflows
Mean forced expiratory flow during the middle half of the FVC
Represents small airway function
Normal value should be >60-70% of predicted
Decreased with small airway obstruction or inflammation
Protocol for Evaluation of Exercise-Induced Shortness of Breath
Goal is to elevate heart rate to a range of 160-180 bpm and sustain that intensity for 6-8 minutes
Mode: treadmill or cycle ergometer
Protocol: brief warmup period
Pulmonary Function Testing
Flow-volume loops performed pre-exercise and 5, 10, and 15 minutes post-exercise
Sometimes done at 20 minutes if still symptomatic
Airway Obstruction
Any disease affecting the diameter of the airways
Mucous production
Inflammation
Bronchoconstriction
Characterized by low flow rates relative to lung volume in such diseases as asthma and COPD
FEV1 in Obstruction
Mild Obstruction 65-80% of predicted Moderate Obstruction 50-65% of predicted Severe Obstruction
Combined Restrictive/Obstructive Ventilatory Defect
Cystic Fibrosis
Excessive mucous production and damage to lung tissue
Bethesda Guidelines
Physical activity guidelines for patients with congenital heart defects, pacemakers, rhythm disturbances, etc
Developed by an expert panel and revised every few years
Helpful when having to make tough clinical decisions
Aortic Stenosis
To asses blood pressure and ECG Abnormal findings: Ischemic changes on ECG Decrease in blood pressure Rarely ectopy
Causes BACKFLOW
Aortic Coarctation
To assess blood pressure response (right arm blood pressures)
Functional capacity
ECG with activity
Abnormal findings:
Elevated systolic or diastolic blood pressure
Hypertrophic Cardiomyopathy
Basically a sick, enlarged heart
strong and thick WITHOUT BP increase
Abnormal findings:
ST segment depression
Decrease in systolic blood pressure with increasing exercise intensity
Ventricular ectopy
Ectopy
early beats
beats stronger or out of rhythm (benign reasons untill it starts coming in groups)
Dysrhythmias
Ectopy PVCs, PACs Sick Sinus Syndrome/ Complete Heart Block Long QT Syndrome Tachyarrhythmias Pacemakers
Long QT syndrome
higher risk of sudden cardiac death
