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TEAK – Bioengineering Artificial Lung & Diaphragm Lesson Plan

T-E-A-K

Traveling Engineering Activity Kits

Biomedical Engineering Kit:The Circulatory and Respiratory Systems

Artificial Lung and Diaphragm Activity

Instructor Preparation Guide:Lung Diaphragm Activity

Bioengineering Overview

Bioengineering is the application of engineering principles to address challenges in the fields of biology and medicine. Bioengineering applies the principles of engineering design to the full spectrum of living systems.

Respiratory System Overview

The two critical pieces of the human respiratory system are the lungs and diaphragm. They work together in order to perform breathing and oxygenate the bloodstream. Each person uses the muscles of the rib cage to breath in; the major rib cage muscle utilized in breathing is the diaphragm. To allow air into the lungs, the diaphragm flattens and tightens. The aAir then enters the lungs through the mouth and trachea, and travels to the bronchial tubes. AThe air then enters gradually smaller airways until it reaches the small air sacs called alveoli.

Figure 1.0 - The Human Respiratory System

Figure 1.1 Lung Diaphragm Interaction

There are around 300 million alveoli in each lung, and; each alveolus is surrounded by blood vessels. Blood in these vessels picks up the surrounding oxygen, and carries it to the body. Carbon dioxide then exits the body through the blood, eventually leaving through an exhalation.

Lung Disease Overview

Lung disease is any disorder that occurs in the lungs or that results in the improper function of the lungs. There are three main types of lung disease:

  1. Airway diseases – Affect the airways that carry oxygen and carbon dioxide to and from the lungs
  2. Lung tissue diseases -- These diseases target the lung tissue
  3. Pulmonary circulation diseases -- These diseases are caused by clotting, scarring, or inflammation of the blood vessels, and cause them to function improperly.

The most common lung diseases include:

  1. Asthma
  2. Chronic bronchitis
  3. COPD (chronic obstructive pulmonary disease)
  4. Emphysema
  5. Pulmonary fibrosis
  6. Sarcoidosis

Figure 2.0 –Emphysema effects on alveoli

Resources

Image Resources

  • Figure 1.0:

Date: February 3, 2009

Time: 5:35 pm

  • Figure 1.1:

Date: February 3, 2009

Time: 5:41 pm

  • Figure 2.0:

Date: February 3, 2009

Time: 5:45 pm

Activity Preparation Guide – Artificial Lung & Diaphragm Activity

Overview

This kit contains activities for students to gain a better understanding of how the respiratory system functions and operates for a typical individual and how engineers study lung and diaphragm behavior in order to design and fabricate medical instrumentation and prosthetics to improve the quality of human life. The main focus of this kit is the lung and diaphragm, and how they work together to perform human breathing.

Learning Objectives

By the end of this lesson, students should be able to…

  • Describe the relationship between the lungs and diaphragm used in breathing, and where artificial lung technology is applied today
  • Utilize engineering roles and work in teams in order to construct an artificial lung and diaphragm
  • Explain how engineers take a complex system and model it more simply
  • Identify similarities and differences between the functional respiratory system and the model in the kit
  • Identify the design considerations an engineer must consider when developing an artificial lung

Engineering Connection

Engineers are currently working to create an artificial lung and diaphragm system in order to give patients in need of a lung transplant time to find a donor. Just as an engineer must acquire data from a biological system in order to model, design, and fabricate a new design, the students participating in this activity will work to create an optimum model of the lung and diaphragm using various materials provided for them in the activity. They will try different balloon sizes, tubing sizes, and stopper types to determine which lung and diaphragm setup is the best choice for their group.

Activity Descriptions

  1. Introductory Discussion: Lung and Diaphragm Interaction 10 Minutes
  • This discussion will be an introductory discussion to the topic of bioengineering and the broad scope that this discipline of engineering encompasses. This discussion will further examine how the respiratory system and how the lungs and diaphragm work together to perform breathing. Students will also be introduced to common forms of lung disease, and the machines that have been engineered to assist in breathing. These machines include ventilators and implantable artificial lungs
  1. Lung Construction Activity:25 Minutes
  • This activity allows students to construct an artificial lung and diaphragm model in order to observe the interaction of the two organs. During this activity students will use the following provided materials, including:a two-liter bottle, two sections of tubing of different lengths, six rubber balloons (2 each of 5”, 9”, 12”), a rubber cover balloon (diaphragm), a wye connector, stoppers with both one and two through holes, and rubber bands.;Tthese materials will be used to construct a model of the lungs and diaphragm. They will then be able to manipulate the latex cover and simulate human breathing. The focus of this activity is to demonstrate and teach the students how engineers are currently developing the technology for construction of artificial lungs, and how engineers design a system to meet a set of customer needs. The activity is also meant to show how the lung and diaphragm work together to achieve breathing.
  1. Group Discussion: 10 Minutes
  • The concluding group discussion will surround encompass the field topic of artificial lung development based on the lung and diaphragm construction design that the students performed constructed in the previous activity. During tThe discussion, it will be shownrecount how engineers are working to design artificial lungs. The instructor will also lead a discussion of the similarities and differences between the artificial lung and diaphragm created during the activity and the artificial lungs being created by physicians today. During the group discussion, graphics and possibly videos will be used to demonstrate and present current progress and developments in the field of artificial lung design.
  1. Engineering Team Roles:

Fluids Engineer– Determines the best way to get air into and out of the lungs with the assistance of the other team members.

Structural Engineer(s) – Responsible for the construction of the model lungs with the assistance of other team members.

Test Engineer – Responsible for testing the model and recording data with the assistance of other team members.

Materials Engineer– Determines material selection for construction of the model with assistance from other members of the team.

New York State Learning Standards

MST / 1 / E / Engineering
Design
Discuss how best to test the solution; perform the test under teacher supervision; record and portray results through numerical and graphic means; discuss orally why things worked or did not work; and summarize results in writing, suggesting ways to make the solution better
MST / 1 / E / Engineering
Design
Plan and build, under supervision, a model of the solution using familiar materials, processes, and hand tools

New York State Health Learning Standards

a.)Standard 3: Resource Management

  1. Students: Distinguish between invalid and valid health information, products, and services.
  2. Students: Analyze how the media and technology influence the selection of health information, products, and services.

New York State Technology Learning Standards

a.)Standard 1: Engineering Design

  1. Engineering design is a repetitive process involving modeling, optimization, and finding the best solution within the given constraints that is used to develop technological and innovative solutions to technical problems.
  2. Students:

• Activate devices.

• Recognize why an object or choice is not working properly.

• Recognize how a defective simple object or device might be fixed.

• Under supervision, manipulate components of a simple, malfunctioning device to improve its performance.

• Design a structure or environment.

b.) Standard 5: Management of Technology

- Students: Must work cooperatively with others on a joint task.

New York State Math Learning Standards

a.)6th Grade Standards

  1. Students will apply and adopt a variety of appropriate strategies to solve problems.
  2. Students will organize and consolidate their mathematical thinking through communication.
  3. Students will determine what can be measure and how, using appropriate methods and formulas.
  4. Students will collect, organize, display, and analyze data.

b.)Mathematics, Science, and Technology

  1. Analysis, Inquiry, and Design Students will use mathematical analysis, scientific inquiry, and engineering design, as appropriate, to pose questions, seek answers, and develop solutions.
  2. Students will understand and apply scientific concepts, principles, and theories pertaining to the physical setting and living environment and recognize the historical development of ideas in science.
  3. Students will apply technological knowledge and skills to design, construct, use, and evaluate products and systems to satisfy human and environmental needs.

New York State Science Learning Standards

a.)Intermediate Standard 1: Analysis, Inquiry, and Design.

  1. T1.1a: Identify a scientific or human need that is subject to a technological solution that applies scientific principles.
  2. T1.3a: Identify alternative solutions base on the constraints of the design

Resources

A.)Gartner, M.J., and P. Litwak. "Development of a Pumping Artificial Lung." Ension, Inc (2002).

B.)

C.)

D.)

E.)

F.)

G.)

H.)

I.)

The Respiratory System

DURATION

45-50 Minutes

CONCEPTS

Bioengineering

Respiratory System

Lung Disease

Artificial Lung Design

Bioengineering Discussion:(5.0 Minutes)

Background Information:

Bioengineering is the application of engineering principles to address challenges in the fields of biology and medicine. Bioengineering is the application of the principles of engineering design to the full spectrum of living systems.

Group Discussion: Bioengineering Background

(Pose the following questions to the group and let the discussion flow naturally… try to give positive feedback to each child that contributes to the conversation)

What do you think bio (biology) means?

  • The study of life and a branch of the natural sciences that studies living organisms and how they interact with each other and their environment.
  • The study of the environment.
  • The study of living organisms and living systems.

What do you think engineering is? What do you think it means to be an engineer?

  • A technical profession that applies skills in:
  • Math
  • Science
  • Technology
  • Materials
  • Structures

Discuss with the students what bioengineering is and the broad scope of areas that bioengineering includes. For this discussion, provide students with examples of bioengineered products and applications.

  • Bioengineering applies engineering principles in the fields of medicine, biology, robotics, and any other living system.
  • Examples of products that have been bioengineered are:
  • Ventilators
  • Stem cells for rebuilding lung tissue
  • Artificial lungs

Respiratory System Introduction: (5 Minutes)

Background Information:

The respiratory system is responsible for supplying the blood with oxygen and releasing unneeded carbon dioxide from the body. The lungs and diaphragm are two critical organs in the respiratory system used in breathing. The lungs contain tiny air sacs, called alveoli, where the oxygen and carbon dioxide exchange occurs. The diaphragm is the muscle which allows the lungs to take in and release air. To inhale, the diaphragm contracts and flattens, allowing air to enter into the lungs. The diaphragm relaxes in order to let air out of the lungs. There are many diseases associated with lungs, such as cancer and emphysema, which may leave humans unable to breathe without assistance. Engineers have created ventilators, which help premature babies breathe and recovering patients after surgery. They are also currently designing artificial lungs, which can be implanted surgically. It is critical that these engineers know how the respiratory system works and functions in conjunction with the rest of the body in order to design solutions to keep humans breathing properly.

Simplified Definitions:

  • Asthma
  • A chronic condition involving the respiratory system in which the airways occasionally constrict and, become inflamed
  • Chronic bronchitis
  • An inflammation of the bronchi (medium-size airways) in the lungs
  • Emphysema
  • A disease of the lungs resulting in decreased respiratory function; emphysema is commonly associated with smoking, chronic bronchitis, or old age
  • Lung Cancer
  • A disease of uncontrolled cell growth in tissues of the lung; lung cancer is usually associated with smoking

Group Discussion: Lung Disease and Biomedical Solutions

(Pose the following questions to the group and let the discussion flow naturally… try to give positive feedback to each child that contributes to the conversation)

What exactly is lung disease?

  • Any disease or disorder that occurs in the lungs or that causes the lungs to not work properly.
  • In some cases, these diseases become so severe that it is impossible for a patient to breathe without the assistance of a machine.

What are some problems you might have with your lungs?

(There may be additional correct answers given)

  • Asthma
  • Chronic bronchitis
  • Emphysema
  • Lung Cancer

Has anyone heard of a ventilator?

  • A device that facilitates breathing in cases of respiratory failure by mechanically introducing fresh air into and out of the lungs and is used until a donor lung is found.
  • Ventilators can assist premature babies in breathing, as well as and help patientsing recovering from surgery patients.
  • Some patients use ventilators to perform long term breathing due to impairmentan impairment from lung disease.
  • External rather than internal. A ventilator is 3-4’ tall in size.

How is an artificial lung different from a ventilator?

  • An artificial lung is implanted inside the body, while a ventilator is used outside the body.
  • Artificial lungs are made to mimic the movements and actions of real lungs (balloons that inflate and deflate, diaphragms that moves, the transfer of oxygen and carboncarbon dioxide into and out of the bloodstream).

Why implant an artificial lung rather than a ventilator?

  • In some cases, a ventilator does not provide enough assistance to patients, and a lung donor must be found; however, this process may take a significant amount of time.
  • An Iimplantable artificial lung will extend the time to find a donor (anywhere from days to months).
  • The device can be left in place until the transplanted lungs are fully functioning.

Artificial Lung and Diaphragm Activity – 25 Minutes

Learning Objectives

By the end of this exercise, students should be able to…

  1. Perform, Understand, and Visualize the process of breathing
  2. Identify the optimum design parameters for the artificial lung and diaphragm model based upon the following customer needs:
  3. Artificial Lung Model must work; that is, the model must simulate breathing in the human lung
  4. Model must allow for the largest air intake possible, to increase oxygen absorption
  5. Model must be as sturdy as possible

Materials

Included in each kit are:

  1. Nalgene Bottle with Top
  2. Red Bag:
  3. One-hole Rubber Stopper
  4. Wye Connector
  5. 3” Tube
  6. Blue Bag:
  7. Two-hole Rubber Stopper
  8. (2) 3” Tubes
  9. (2) 5” Tubes
  10. White Bag:
  11. (2) 12” Balloons
  12. (2) 9” Balloons
  13. (2) 5” Balloons
  14. Balloon Diaphragm
  15. (2) Rubber Bands
  16. Green Bag:
  17. (4) Activity Role Tags
  18. Activity Handout

Procedure

  1. Divide students into groups of 4-5.
  1. Give each group a kit and the activity handout.
  1. Before the students open their kits, discuss the design parameters with them. Make sure all students understand the purpose of the activity and what they are supposed to be doing.
  1. Walk the students through the building of their first lung configuration. Let each team member follow their given role, and walk around the room to make sure everyone understands what they are doing.
  1. Instruct students to open their kits and begin the activity.

NOTE: There are a total of 12 different lung and diaphragm configurations that the students can construct. Since it is unlikely that a group will complete all 12 setups, make sure that they are testing the ones they think will be the most successful.

Expected Results

  1. Students should not see a noticeable difference in the air intake rate when using different tube lengths, as the difference should be too small to detect. However, Tthey should notice, however, that the setup is much less sturdy.
  1. Students should notice that a much larger amount of air that is taken in by the 12” balloons.
  1. Students should notice the flimsy nature of the two-tube design, which can result in lung twisting and collision.

End Artificial Lung and Diaphragm Activity

Concluding Discussion

(Pick and choose depending on student questions/responses to the activity worksheet)

How does this artificial model differ from the human respiratory system?

There are many correct answers to this question. Examples of correct responses are:

  • Living tissue
  • Diaphragm is a muscle
  • Trachea

In today’s activity, we designed the tube configuration, tube length, and balloon size for our artificial lungs. What elsecould bioengineers change or improve to design a more advanced artificial respiratory system?

There are many correct answers to this question. Examples of correct responses are:

  • Size of the lung cavity (bottle size)
  • Thickness of the lungs/diaphragm
  • How to transfer oxygen once it is in the artificial lung

Revisions

Date / Changes Made / Changes Made By
9/15/2009 / Changed respiratory system introduction, restructured the activity handout by adding the procedure and a design chart, updated engineering evaluation to match new handout, added to the respiratory system intro. / Heather Godlewski
01/11/2010 / ChangesSpelling and grammar corrections made to lesson plan, changed on website/share folder, but didn’t re-print. Marked corrections with initials. / Konrad Ahlin
01/13/2010 / Added pictures to activity handout / Konrad Ahlin