This document provides an overview of pathophysiology and discusses the cell, the cardiopulmonary system, and shock. It describes how diseases can affect cellular function and the delicate balance of ventilation and perfusion needed to sustain life. The key systems involved in gas exchange and circulation are outlined, including potential points of dysfunction that can compromise the body's ability to provide oxygen and remove waste from tissues.
Planning Your Time: Plan 120 minutes for this chapter.
The Cell (20 minutes)
The Cardiopulmonary System (60 minutes)
Shock (20 minutes
Pathophysiology of Other Systems (20 minutes)
Note: The total teaching time recommended is only a guideline.
Core concepts:
The cell, cellular metabolism, and results of the alteration of cellular metabolism
The cardiopulmonary system and its combined respiratory and cardiovascular functions
The respiratory system and the importance of oxygenation and ventilation
The cardiovascular system and the movement of blood
The principles of perfusion, hypoperfusion, and shock
Disrupted physiology of major body systems
Covers Objective: 7.1
Teaching Time: 20 minutes
Teaching Tips: The cell is a difficult concept to apply to everyday life. Consider using multimedia presentations to add visual context. The most important part of this lesson is the discussion of metabolism. It lays the groundwork for an understanding of respiration and perfusion. Spend time in this section.
Covers Objective: 7.2
Point to Emphasize: Metabolism is the process of turning nutrients into energy at the cellular level. Under normal circumstances, this process requires glucose and oxygen.
Discussion Topic: Explain how a diminished supply of glucose alters metabolism.
Covers Objective: 7.2
Point to Emphasize: There are a variety of structures within a cell. Each has a specific function. Common cell structures include the nucleus, the endoplasmic reticulum, and the mitochondria.
Discussion Topic: Describe the structures of a cell.
Covers Objective: 7.3
Knowledge Application: Have students work in small groups. Assign each group a disorder (such as dehydration) and ask group members to research and report on how that condition might impact metabolism. Discuss their findings.
Critical Thinking: Diabetics occasionally suffer from a condition called hyperglycemia. How might this condition affect metabolism?
Covers Objective: 7.3
Talking Points: Think of glucose as crude oil, and the mitochondria as the refinery that makes it into ATP (gasoline) with the help of oxygen and water. Without ATP, the cell cannot function effectively and may stop working (die).
Covers Objective: 7.3
Covers Objective: 7.3
Point to Emphasize: Anaerobic metabolism occurs when oxygen is depleted or absent. It is a very inefficient method of creating energy.
Discussion Topic: Discuss how the body adapts to altered metabolism. Describe the changes that occur.
Covers Objective: 7.3
Knowledge Application: Assign homework. Have students research the concept of anaerobic metabolism. Ask them to discuss the effects of anaerobic metabolism on at least three body systems.
Covers Objective: 7.3
Knowledge Application: Assign homework. Have students research the concept of anaerobic metabolism. Ask them to discuss the effects of anaerobic metabolism on at least three body systems.
Covers Objective: 7.3
Teaching Time: 60 minutes
Teaching Tips: Cardiopulmonary function is a large lesson, but it has many smaller elements. Teach it in a developmental manner. Use small building blocks to create the larger structure. This lesson will be made easier because students have completed the anatomy lessons of Chapter 6. Build upon previously discussed concepts. Use real-life examples and "war stories" to illustrate complex points. This section lends itself well to multimedia graphics. Use video clips and graphics to demonstrate body systems.
Covers Objective: 7.4
Covers Objective: 7.4
Covers Objective: 7.4
Covers Objective: 7.5
Covers Objective: 7.5
Point to Emphasize: Alveolar ventilation is related to both rate and volume of respiration.
Covers Objective: 7.5
Point to Emphasize: Respirations can be disrupted by obstruction or by destruction of the key anatomical structures.
Discussion Topic: Explain how bronchospasm might impact rate, tidal volume, and alveolar ventilation.
Covers Objective: 7.5
Knowledge Application: Have students work in small groups. Assign a specific disease or injury to each group and have the group report on how that disease or injury might impact normal function.
Covers Objective: 7.5
Covers Objective: 7.5
Discussion Topic: Discuss how sepsis might interfere with oxygen delivery to the cells.
Covers Objective: 7.6
Covers Objective: 7.9
Covers Objective: 7.9
Covers Objective: 7.7
Point to Emphasize: The heart, blood vessels, and blood combine to provide oxygen to the cells. Disruption at this level interrupts perfusion.
Covers Objective: 7.7
Covers Objective: 7.7
Covers Objective: 7.9
Covers Objective: 7.9
Covers Objective: 7.9
Covers Objective: 7.9
Covers Objective: 7.9
Covers Objective: 7.5
Covers Objective: 7.5
Covers Objective: 7.5
Discussion Topic: Describe how an extremely fast heart rate might actually drop cardiac output.
Covers Objective: 7.5
Covers Objective: 7.7
Knowledge Application: Ask students to define the necessary components of perfusion. What elements must function in order for perfusion to occur? Discuss.
Teaching Time: 20 minutes
Teaching Tips: Emphasize that shock is the inability to meet the oxygen demands of the tissues and that it may result from many types of conditions; medical and traumatic alike.
Covers Objective: 7.7
Point to Emphasize: Shock occurs when cells lack the oxygen they need for metabolism.
Discussion Topic: Define shock.
Class Activity: Have students work in small groups. Assign each group a key component of the cardiopulmonary system. Have the groups present the role of their components to the class. Discuss how the components work together.
Covers Objective: 7.9
Covers Objective: 7.8
Knowledge Application: List different types of shock. Have students discuss which part of the cardiopulmonary system each type of shock disrupts.
Critical Thinking: Now that you understand how perfusion is disrupted, discuss how the cardiopulmonary system might change in response to hypoperfusion. How might you tell, from external signs, that these changes are occurring?
Teaching Time: 20 minutes
Teaching Tips: This lesson is designed to provide only a brief overview. Pathophysiology is a much larger topic. Discuss how students can continue to learn in this area. Use real-life examples. Adults grasp pathophysiology best when they can apply it to actual situations. For each subsection of disorder, discuss actual examples and move from theory to reality. Link dysfunction of the nervous, endocrine, digestive, and immune systems to your previous discussions of normal function.
Covers Objective: 7.9
Point to Emphasize: The body is 60% water. Several factors cause the distribution of fluid throughout the body.
Critical Thinking: A burn can lead to severe fluid imbalances. How do burns affect fluid levels?
Covers Objective: 7.9
Point to Emphasize: The body is 60% water. Several factors cause the distribution of fluid throughout the body.
Critical Thinking: A burn can lead to severe fluid imbalances. How do burns affect fluid levels?
Covers Objective: 7.9
Discussion Topic: Explain how fluid is distributed throughout the body.
Covers Objective: 7.9
Covers Objective: 7.11
Point to Emphasize: Nervous system injuries can be devastating and life threatening; they can affect the airway, breathing, and circulation.
Knowledge Application: Have students work in small groups. Assign a specific pathophysiology. Have the groups research their dysfunction and present their findings to the class. Findings should include a discussion of how their dysfunction interferes with normal function of the specific body system.
Covers Objective: 7.11
Discussion Topic: Discuss the impact of nervous system dysfunction on the body systems.
Covers Objective: 7.11
Discussion Topic: Discuss the impact of nervous system dysfunction on the body systems.
Covers Objective: 7.13a
Point to Emphasize: The endocrine system controls body functions through chemical messages.
Covers Objective: 7.13a
Covers Objective: 7.13a
Discussion Topic: Explain how endocrine dysfunctions might impact other body systems.
Covers Objective: 7.13b
Covers Objective: 7.13b
Point to Emphasize: The digestive system allows nutrients to enter the body and waste products to leave.
Covers Objective: 7.13b
Covers Objective: 7.13c
Point to Emphasize: Hypersensitivity reactions are an exaggerated immune response.
Discussion Topic: Discuss how allergic reactions are related to the immune system.
Covers Objective: 7.13c
Point to Emphasize: Hypersensitivity reactions are an exaggerated immune response.
Discussion Topic: Discuss how allergic reactions are related to the immune system.
Talking Points: The lungs (pulmonary system), heart, blood vessels, and the blood itself (cardiovascular system) work in concert to perform cardiopulmonary functions. The primary function of the cardiopulmonary system is to deliver oxygen and nutrients to the cells and to remove waste products from the cells. These basic operations rely on the coordinated movements of blood and air. Interruption of any part of this balance results in a compromise to, or even a failure of, the system.
Talking Points: Shock occurs when the regular delivery of oxygen and nutrients to cells and the removal of their waste products is interrupted. Without a regular supply of oxygen, cells become hypoxic and must rely on anaerobic metabolism. Lactic acid and other waste products accumulate and harm the cells. Without the removal of carbon dioxide, the buildup of harmful waste products is accelerated. Unless it is reversed, shock will kill cells, organs, and eventually the patient.
Talking Points: The patient's sepsis will affect the body's ability to dilate and constrict blood vessels, thereby decreasing it's ability to regulate blood pressure in response to any additional illnesses or injuries. BLS care for shock should be initiated to include oxygen, warmth, and a position of comfort. ALS should be considered for fluid therapy.