I Cant Stop Coughing Case Study with Worksheet PDF

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Study case for cant stop coughing. It is for an assignment for my physiology class. Answers provided. The assingment is from a haiku website....

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I Can’t Stop Coughing: A Case Study 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.

Short Answer Questions: 1. Describe the relationship between intrapulmonary pressure, atmospheric pressure, and air flow during normal inspiration and expiration, referring to Boyle’s law. Inspiration is an active process whereby the contracting diaphragm and internal intercostals increase the dimensions of the thorax. Boyle's Law states that the volume of a gas in a container is inversely related to the pressure of the gas. So, when the volume of a gas increases, its pressure decreases, and vice versa. Here the container is the lungs: when the lung volume increases, then intrapulmonary pressure drops a couple of millimeters below atmospheric pressure, and air flows into the lungs down its pressure gradient. When the

muscles of inspiration relax, the thoracic volume decreases and intrapulmonary pressure rises above atmospheric pressure. 2. Resistance varies in Mike’s conducting airways. Using your understanding of respiratory anatomy, explain where in his airway the resistance is highest and why. Resistance is highest in the medium-sized conducting airways and lower in the large airways because of their large diameters. As the air travels into the medium-sized bronchi, it faces greater resistance due to the drop in diameter of the airway. Although the diameter of the airways continues to drop, the resistance falls dramatically as they continue to branch all the way down to the terminal bronchioles. Even though the terminal bronchioles are smaller in diameter than the medium-sized bronchi, there are many, many more of them. When added together, these smaller airways actually have a much greater cross-sectional area than the medium-sized airways. The greater the total cross-sectional area of airways, the lower the resistance through that region. 3. Several physical factors that influence the efficiency of pulmonary ventilation are compliance, alveolar surface tension, and airway resistance. Briefly describe each factor and identify the one that is affecting Mike’s efficiency of breathing. Lung compliance is the ease with which the lungs inflate. Normally, the lungs are very distensible with just the right amount of elastic recoil to allow easy inspiration and passive expiration. 4. What must happen to Mike’s intrapulmonary pressure in order for him to maintain normal air flow during inhalation and exhalation when he is having one of his asthma attacks? Air flow = pressure gradient/resistance. When airway resistance increases (as it does with the bronchoconstriction in asthma), the pressure gradient must increase in order to maintain normal air flow. The pressure gradient is the difference between intrapulmonary and atmospheric pressures, normally about 2 mmHg with quiet breathing. 5. How does Mike’s body make the necessary changes in intrapulmonary pressure to maintain normal air flow when he is experiencing cold-induced asthma? Accessory muscles, such as the sternocleidomastoid, pectoralis minor, and scalenes, are recruited to help increase the thoracic cage dimensions on inspiration. They do so by assisting in drawing the thoracic cage upward. 6. When Mike is experiencing an asthmatic attack, his forced vital capacity (FVC) is 65%, and his FEV1 is 65%. Are these values normal? Knowing how one performs FVC tests, explain these test results in Mike’s case. (Assume that Mike and the doctor have performed an accurate test.) Both the FVC and FEV1 should be greater than or equal to 80%, so Mike's values indicate respiratory dysfunction. 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. 7. Albuterol is a selective beta-2 adrenergic agonist, which means it specifically activates beta-2 adrenergic receptors on smooth muscle in the airways. How does this improve Mike’s asthma? Activation of beta-2 adrenergic receptors on bronchial smooth muscle sets into motion a second messenger system, which leads to relaxation of smooth muscle. This causes the bronchi and bronchioles to dilate. Bronchodilation decreases resistance and ameliorates the wheezing, coughing, and shortness of breath....