PDF test #3

Noninvasive methods

CO2 rebreathing, soluble gas, and Doppler (ultrasound) techniques

Invasive methods

CO by the direct Fick method or by thermal dilution. The invasive methods require placement of a pulmonary artery catheter

In healthy patients, the ventilatory reserve (breathing reserve) is typically

20% to 40%

When an exercise blood gas is indicated, the sample should be obtained within

15 seconds of peak exercise

in a ramp protocol, the ergometers resistance is

increased continuously at a predetermined rate (usually measured in watts per minute)

Unlike the treadmill, with a cycle ergometer

oxygen can be

reasonably estimated if the pedaling speed and resistance are carefully measured

primary indications for performing exercise tests

dyspnea on exertion, pain (especially angina), and fatigue

Six-Minute Walk Test (6MWT) is a simple test that does not require any

sophisticated equipment

Steady-state tests are designed to access cardiopulmonary function under conditions of

constant metabolic demand

Progressive multistage exercise tests examine the effects of

increasing workloads on various cardiopulmonary variables without allowing a steady state to be achieved

Borg Scale

a numerical scale used to rate perceived exertion during exercise testing

Incremental Shuttle Walk Test (ISWT)

simple field test that uses a structure increasing pace to define function exercise capacity

Endurance Shuttle Walk Test (ESWT)

a simple field test that is a constant walking pace based on the outcome of the

incremental shuttle walk test

Work is normally expressed in

kilopond-meters (kpm)

One kilopond-meter equals the work of moving a

1-kg mass a vertical distance of 1 m against the force of gravity

Energy

expressed by oxygen consumption in liters or milliliters per

minute (STPD) or in terms of metabolic equivalents (METs)

cardiac output equation

CO = HR x SV

Observation of the breathing kinetics or breathing strategy of a

patient during exercise can be an important adjunct in the interpretation of the exercise

results

The normal response to exercise is to increase the ________ VT at low and

moderate workloads

Oxygen consumption

the volume of oxygen taken up

by the exercising (or resting) patient in liters or milliliters per minute

Measurement of and the analysis of exhaled gases during exercise allow a noninvasive

estimate of the

anaerobic threshold (AT)

Minute ventilation

total volume of gas moved into and out of the

lungs each minute

Rating of Perceived Exertion (RPE)

A scale used during exercise testing that allows the patient to signal a numeric

value related to his or her perception of exertion

Lactic Acid

An acid produced by anaerobic metabolism at high levels of work

A straightforward test in an uncomplicated infant can be safely performed by minimal

personnel with the use of an oral sedating agent, such as

chloral hydrate (CH)

Regardless of the agent chosen

safety is the primary concern

Babies may respond to hypoxia by dynamically elevating their FRC to create a

positive end expiratory pressure (PEEP) like

effect (dynamic FRC)

Young infants will hold their breath when their airway is occluded. This phenomenon is

known as the

Hering-Breuer reflex and is present in children until

approximately 1 year of age

Airway resistance

reflects the nonelastic airway and tissue forces

resisting gas flow

Respiratory Inductive Plethysmography (RIP)

a noninvasive method

of thoracoabdominal motion analysis using respiratory tracings to monitor movement from

the rib cage and abdomen simultaneously

Techniques have been developed to raise the

volume of the infant’s lungs

before a rapid thoracoabdominal compression

This may be accomplished by

stacking inspirations or by a method known as the raised volume technique.

What is the most common type of PFT test performed in the pediatric population?

spirometry

the chest wall of the infant is extremely

compliant, unlike that of an adult

The measurement of

exhaled nitric oxide (eNO) has been proposed as

an index of airway inflammation, such as occurs in asthma

One time constant

represents the amount of time to expire approximately

2/3 of the tidal volume

methacholine level at which this 20% decrease occurs is called

provocative concentration

FIve (5) breath dosimeter method

defined as a quantitative

challenge test activated during inspiration to deliver a consistent volume of drug for each

0.6-second actuation of the dosimeter

2-minute tidal breathing method

defined as a method of

delivering methacholine to the airway where only a nebulizer is used

Mannitol is a hypertonic stimulus, and inhalation increases the osmolarity of the airway that

subsequently leads to the release of

inflammatory mediators from mast

cells and basophils

Exercise induced bronchospasm (EIB) a respiratory disorder typified by bronchospasm

during or immediately after

vigorous exercise

At one time, the International Olympic Committee Medical Commission expressed a

viewpoint that

eucapnic voluntary hyperpnea or

hyperventilation (EVH) was the optimal laboratory challenge to confirm that an athlete has

exercise-induced bronchoconstriction (EIB).

Most clinicians consider the test result positive when inhalation of methacholine

precipitates a 20% decrease in FEV1. The methacholine concentration at which this 20%

decrease occurs is called

provocative concentration (PC20)

Histamine

chemical compound that causes dilation and increased permeability of blood vessels that

play a role in allergic reactions

Methacholine

potent chemical that increases the parasympathetic muscle tone in the airways when

inhaled; used to induce bronchoconstriction to test for hyperreactivity of the airways