Week 12: Spirometry - Respiratory Physiology Lab

Which amount of surfactant resulted in the greatest amount of airflow?

4

Under normal conditions, the forced expiratory volume is normally _______.

75 - 85% of the vital capacity

As the thoracic cavity and lungs recoil and return to their original position, the pressure inside the lungs increases and we exhale. This relationship is described by __________.

Boyle's law

What is the primary muscle of inspiration?

Diaphragm

You've just finished running five miles. Which of the following best describes your breathing? -Exhalation due to relaxation of the diaphragm -Exhalation due to the contraction of the internal intercostal muscles and the abdominal muscles -Pressure in the lungs decreases resulting in exhalation -Exhalation due to the expansion of the thoracic cavity -Exhalation due to the relaxation of the intercostal muscles

Exhalation due to the contraction of the internal intercostal muscles and the abdominal muscles

Steve may have emphysema, which is a type of obstructive lung disease. The alveoli are damaged and may collapse, which interferes with pulmonary ventilation. Choose the lung volumes and capacities that you would expect to be above normal in Steve's condition.

FRC ERV RV Obstructive lung diseases are diseases that decrease a patient's ability to exhale air. The recoil of the lungs is decreased, which decreases the amount of air that can be exhaled and increases the amount of air remaining in the lungs. This would increase the RV, ERV and FRC.

Drag and drop the correct terms on the left to complete the sentences.

Functional residual capacity (FRC): volume of air remaining in the lungs after a normal expiration Tidal volume (TV): volume of air inhaled or exhaled with each breath under resting conditions Inspiratory reserve volume (IRV): volume of air that can be forcefully inhaled following a normal inspiration Expiratory reserve volume (ERV): volume of air that can be forcefully exhaled after a normal expiration Total lung capacity (TLC): the maximum amount of air contained in the lungs after a maximum inspiration Inspiratory capacity (IC): the maximum amount of air that can be inspired after a normal expiration Residual volume (RV): volume of air remaining in the lungs after a forced expiration Vital capacity (VC): the maximum amount of air that can be expired after a maximum inspiration

Match the term with the best description.

Inspiration is the movement of air into the lungs. Expiration is the movement of air out of the lungs. Atmospheric pressure is the pressure of the air around us. Intrapulmonic pressure refers to the pressure of air in the lungs. Active process requires contraction of skeletal muscles. When air leaves the lungs, no muscular contractions are involved in a Passive process. Eupnea is the term for the type of breathing you experience while sitting in a comfortable chair and watching your favorite show.

Match these vocabulary terms to their meanings.

Intrapleural pressure is the pressure within the pleural cavity. Normal breathing is called eupnea. Hyperpnea is faster than normal breathing. A(n) spirometer measures the amount of air a person can breathe in and out.

Recall from the video the demonstration on how to use a spirometer to measure vital capacity (VC). Place the steps to measure VC in the correct order from left to right.

It is important to strain to inhale the maximum amount of air that you can when measuring vital capacity.

How did the total air flow in this trial differ from that in the previous trial in which the pleural cavities were intact?

It was cut in half.

How did the pressure in the left intrapleural cavity change when the valve was opened?

It went from a negative number to zero and the pressure in the intrapleural cavity equalized with the atmospheric pressure.

Clinical Case Study: I Can't Stop Coughing: A Case on the Respiratory System

Mike is sitting in his athletic training suite feeling sorry for himself. He moved from Southern California to play soccer at Northern Minnesota University (NMU) as a highly recruited player. All was well until he got sick with a miserable cold. He soon recovered, but now he finds himself with a lingering dry cough and difficulty catching his breath any time he exerts himself, which is every day! He also notices it has gotten worse as the weather has become colder. To make things worse, Mike feels, and looks, like he's out of shape, so his coach has been criticizing him for dogging it. A few days later, Mike relays his story to JP, the head athletic trainer at NMU. "I'm thinking my cold is coming back, or something else is wrong with me. When I'm just hanging out, like now, I feel fine. But as soon as I start to run I get winded and can't stop coughing." JP listens to Mike's breathing sounds with his stethoscope, but hears nothing abnormal. So he tells Mike to come back as soon as the symptoms return during soccer practice. Twenty minutes later, Mike is back in the athletic training suite, audibly wheezing, coughing, and short of breath. The team physician, Dr. McInnis, happens to be there and performs a complete physical exam. He also does pulmonary function tests with Mike using spirometry, including a forced vital capacity (FVC) and forced expiratory volume in one second (FEV1). He instructs Mike to take a maximal inhalation and then exhale as forcefully and maximally as possible into the spirometer. Based on his findings, Dr. McInnis tells Mike he thinks he is experiencing cold-induced bronchoconstriction (also called cold-induced asthma), which is made worse by exertion. The doctor explains to Mike that his recent upper respiratory infection probably inflamed his airways, making them hypersensitive and reactive to irritants, such as cold and physical exertion. When Mike exercises in the cold, autumn afternoons of Minnesota, his sensitive airways temporarily bronchoconstrict, causing the symptoms he is experiencing. Asthma is almost always a reversible condition. Dr. McInnis prescribes two puffs of an albuterol inhaler, to be used 10 minutes before a bout of exercise in the cold.

Individuals with emphysema have a form of chronic obstructive pulmonary disease (COPD). As you learned, these individuals have lost the recoil in the lungs and air is therefore trapped in their lungs. Predict Steve's arterial blood pH and PaCO2 (the partial pressure of CO2 in arterial blood and dependent on exhalation).

PaCO2 = 50 mm Hg, pH = 7.30 Alterations in the body's ability to eliminate CO2 affect the pH of the blood. Arterial blood gases, or ABGs, are often done to assess the arterial blood concentration of CO2, O2, and the blood pH.

What is the mechanical process of moving air into and out of the lungs?

Pulmonary ventilation Pulmonary ventilation, commonly known as breathing, is divided into two phases: inspiration and expiration. This mechanical process depends on the changes in volume that occur within the thoracic cavity.

Drag and drop the terms on the left to match the appropriate descriptions on the right.

Pulmonary ventilation: breathing; moving air into and out of the lungs. Intrapulmonic pressure: the pressure inside the lungs. Inspiration: movement of oxygen-rich air into the lungs. Expiration: emptying carbon-dioxide-laden air from the lungs into the atmosphere.

With an acute asthma attack, ________________ increased when compared to normal values.

RV

After reviewing the structural differences and similarities of the vessels of the systemic circulation, place the description into the correct bin.

Respiration has three phases: pulmonary ventilation, external respiration, and internal respiration. Pulmonary ventilation is the movement of air in and out of the lungs. External respiration is the exchange of gases between the lungs and blood. Internal respiration is the exchange of gases between blood and tissue.

Why is normal exhalation passive?

Respiratory muscles are relaxing and elastic tissue in the lungs recoils.

Clinical Scenario: Respiratory Physiology - Spirometry and Lung Disease

Steve Smith is a 58-year-old Caucasian male who is at his doctor's office for an annual physical exam. Steve is 5'10" and weighs 170 pounds. He smokes two packs of cigarettes per day, and he began smoking when he was 18 years old. His respiratory rate is 26 breaths per minute, his blood pressure is 150/90 mm Hg, and his resting pulse is 92 bpm. He mentions his concerns that it is harder to breath and he often feels like he can't catch his breath, especially when going up the stairs in his house. Sometimes, he wheezes when going up his stairs. He has a chronic cough and you notice that his chest is wider, almost shaped like a barrel.

What is the difference between TLC and VC?

TLC includes RV; VC does not include RV.

Which of the following statements describes the conditions of a pneumothorax?

The presence of air in the pleural cavity. The pleural cavity is normally a closed, fluid-filled space between the parietal and visceral pleura. The entry of air into this space constitutes a pneumothorax and results in the partial or complete collapse of the affected lung. Treatment for a pneumothorax typically involves removal of the excess air with the insertion of a tube or needle into the chest.

Match these prefixes, suffixes and roots to their meanings.

The root word hyper- means "over" or "above." The root word intra- means "within" or "inside." The root word -pnea means "breathing." The root word spiro- means "to breathe."

Match the term with the best description.

Tidal volume is the amount of air you inhale and exhale while breathing normally. Inspiratory reserve is the amount of air forcibly inhaled after a normal inhalation. Expiratory reserve is the amount of air forcibly exhaled after a normal exhalation. Vital capacity is the maximum amount of air that can be exhaled after maximum inhalation. Residual volume is the volume of air remaining in the lungs after maximum exhalation. Minimal volume is the residual air in the lungs even after they collapse. Total lung capacity is the total of all respiratory capacities. Respiratory rate is the number of breaths per minute.

Predict the vital capacity of a 20-year-old 5'5" female who weighs 120 pounds using the equation below: VC = (0.041) H - (0.018) A - 2.69

VC = (0.041)(165.1) - (0.018)(20)- 2.69 VC = 6.4091 - 2.69 VC = 3.71 L

Drag and drop the terms at the left to match the appropriate descriptions at the right.

Vital capacity (Vc): IRV + TV + ERV. Tidal volume (TV): amount of air normally inhaled or exhaled. Inspiratory reserve volume (IRV): volume of air that can be forcefully inhaled after normal inhalation. Expiratory reserve volume (ERV): volume of air that can be forcefully exhaled after normal exhalation. Residual volume (RV): volume of air that cannot be forcefully exhaled. Total lung capacity (TLC): vital capacity plus residual volume. Respiratory rate: number of breaths per minute. Minute volume: respiratory rate multiplied by tidal volume. Spirometer: measures respiratory volumes. Pulmonary ventilations: inspiration and expirations.

Because the bell jar in the model lung cannot move, any changes in volume are a result solely of the movement of the rubber diaphragm. Match the position of the rubber diaphragm to changes in volume and pressure inside the bell jar and balloon size.

When operating the model lung, pulling the rubber diaphragm down inflates the balloons simulating the flow of air into the lungs during inspiration. Conversely, pushing the rubber diaphragm up deflates the balloons simulating the flow of air out of the lungs during expiration.

Mike's wheezing and shortness of breath is due to asthma, and obstructive pulmonary disease. Do the following data tend to confirm asthma? FEV1 = 55%; FVC = 65%. (Assume that Mike and the doctor have performed an accurate test.)

Yes. One would expect decreased FEV1 and FVC values, such as these with asthma. Both the FVC and FEV1 should be > or = 80%, so Mike's values indicate respiratory obstruction (given that he has performed the test accurately). Asthma is classified as an obstructive disease because the reactive airways narrow and increase resistance, thus obstructing normal air flow. Despite a maximal effort, Mike cannot generate enough intrapulmonary pressure to compensate entirely for the excessive resistance, so normalized air flow on exhalation, particularly in the first second, cannot happen. Note: Restrictive pulmonary diseases also have reduced FVC, but are likely to have normal FEV1.

Steve is most likely using accessory muscles to help him breath. Choose which muscles Steve would be using.

abdominals internal intercostals The diaphragm is the prime mover of inspiration. If the diaphragm should become paralyzed, breathing will cease (apnea). Accessory muscles contract to change the shape of the thorax to increase volume differences, which allow more air to move into or out of the lungs. The scalene and external intercostal muscles are important for assisting with deeper inhalations. The internal intercostal and abdominal muscles are used for forced expirations.

A normal FEV1% was seen with _______.

acute asthma attack plus inhaler

Mike has difficulty breathing when he's experiencing cold-induced asthma due to a change in which of these physical factors? -lung compliance -lung elasticity -airway resistance -alveolar surface tension

airway resistance

In this activity, the pressure in the pleural cavity would be located _______.

between the bell jar and the outer wall of the lung

During an acute asthma attack, the obstruction is caused by _______.

bronchiole smooth muscle spasms

Albuterol is a selective beta-2 adrenergic agonist. The intended beta-2 adrenergic effect is ____________. The undesirable effect of beta-1 adrenergic stimulation is ____________.

bronchodilation; rapid heart rate Albuterol targets only beta-2 adrenergic receptors of bronchial smooth muscle causing selective bronchodilation without tachycardia. Activation of beta-1 adrenergic receptors of the heart causes an increase in heart rate.

The minute ventilation is _______.

calculated by multiplying the rate of respiration times TV

There are several types of COPD disorders. Which of the following is another example of a COPD?

chronic bronchitis Chronic bronchitis and even asthma are characterized as obstructive lung diseases. These diseases reduce alveolar ventilation and the movement of air. They are chronic diseases characterized by coughing, wheezing, and shortness of breath. COPD is the third leading cause of death in America, and claimed the lives of 134,676 Americans in 2010. (Source: American Lung Association)

In order to maintain a normal air flow during inspiration while Mike is experiencing cold-induced asthma, his body must ___________. -decrease intrapleural pressure -decrease the pressure gradient between atmospheric and intrapulmonary pressure -decrease intrapulmonary pressure more than usual -increase intrapulmonary pressure

decrease intrapulmonary pressure more than usual Decreasing intrapulmonary pressure such that it becomes more negative than atmospheric pressure (and increases the pressure gradient) allows air flow to be maintained in the face of higher airway resistance.

Which of the following is(are) obstructive conditions?

emphysema and an acute asthma attack

Which of the following is a passive process?

expiration

When the radius of the airway was decreased, _______.

expiratory reserve volume decreased

With emphysema, the muscles that contract with normal exhalation include which of the following?

internal intercostals and abdominal muscles

The pressure in the pleural cavity is called the _______.

intrapleural pressure

When the diaphragm contracts, _______.

it flattens out

The pressure in the pleural cavity is _______.

less than the pressure in the alveoli and less than atmospheric pressure

Under normal conditions airway resistance is highest in which segment of the conducting airway? -primary bronchi -medium-sized bronchi -respiratory bronchioles -terminal bronchioles

medium-sized bronchi Resistance is highest in the medium-sized bronchi. Resistance is relatively lower in the large bronchi because of their large diameters. Resistance increases and peaks in the medium airways, then drops dramatically as the airways branch into bronchioles. The reason there is a drop in resistance across the bronchioles (even though they are smaller in diameter) is that there are so many of them, dramatically increasing the total cross-sectional area of the airways.

Which of the following resulted in an increase in tidal volume above the normal value?

moderate exercise

All of the following physical factors affect the mechanics of pulmonary ventilation (breathing) EXCEPT _____________. -alveolar surface tension -airway resistance -pulmonary blood flow -lung compliance

pulmonary blood flow

What does a spirometer measure?

respiratory volumes There are two main types of spirometers: non-recording "dry" spirometers and "wet" spirometers, which are available in both recording and non-recording varieties. In non-recording spirometers, an indicator moves as air is exhaled, so only expired air volumes can be measured directly. In recording spirometers, both inspired and expired gas volumes are measured.

Dr. McInnis wants to obtain Mike's greatest possible vital capacity measurements. Which of the following body positions should Mike assume?

standing When standing, inspiration is aided by gravity's downward pull on the diaphragm, increasing the height of the thorax, and the thoracic cage is free, anteriorly and posteriorly, to expand the diameter of the thorax.

During forced exhalation, _______.

the internal intercostals contract

What is the driving force for the movement of air into the lungs?

the pressure gradient

Without surfactant, _______.

the surface tension of the liquid in the alveoli would be greater and the alveoli would collapse

Which of the following describes the volume of air exhaled during passive breathing?

tidal volume

Which of the following would increase with exercise?

tidal volume, frequency of breathing and minute volume

Dr. McInnis measured Mike's forced vital capacity (FVC). The vital capacity includes what three lung volumes?

tidal volume, inspiratory reserve volume, and expiratory reserve volume