Title III Erie Community College Algebra Skills Assignment Health Sciences - Respiratory Care Interdisciplinary Course Materials (ICM) Course: MT 006 Course Outline Topic: Ratio, Proportion, Linear Inequalities Project Title: Oxygen Flow Project description: Students will be given several scenarios in which they will use Air:Oxygen ratios provided to setup and solve proportions or linear inequalities to find solutions to the problems posed. Author: Gail Butler (North Campus Mathematics/C.S. Department) Curriculum Expert: James Bierl (North Campus Respiratory Care Department) Semester Created: Fall 2008 A. Essential Question What is the total flow of oxygen being delivered by an air entrainment mask delivering a certain percentage of oxygen? B. Introduction An air entrainment oxygen mask mixes room air with pure oxygen so as to deliver a precise amount of oxygen to a patient. In this project, you will investigate several scenarios involving the use of air entrainment masks in respiratory therapy. You will use your knowledge of ratios and proportions to solve the problems. C. Basic Directions All work is to be shown in an organized fashion on separate paper. Your work should be clearly labeled. In addition to correct answers, neatness and legibility are required for full credit. You may use a calculator for the computations. If necessary, follow the problem specific directions for rounding your answers. You are to complete this project on your own. It will count toward your final grade as indicated in your instructor’s syllabus. Erie Community College Title III Grant D. Things to Learn Before Starting the Project 1. Know how to write and simplify ratios. 2. Know how to use ratios to write a proportion. 3. Know how to solve proportions. 4. Know how to solve word problems algebraically. 5. Know how to solve linear inequalities. E. The Project Assignment The following Air: Oxygen ratios will be used in the problems you will be asked to solve. What do these numbers mean? For example, in the first ratio (24% O2 ) for every 1 liter of pure oxygen flow to the mask, the mask entrains (“sucks in”) 25 liters of room air (the air already has some oxygen in it but the mask is adding 1 liter of pure oxygen to it.) Air : Oxygen Ratios 24% O2 30% O2 35% O2 40% O2 50% O2 60% O2 = = = = = = Air: Oxygen (pure) 25 : 1 8:1 5:1 3:1 1.7 : 1 1:1 Problem #1 A respiratory therapist is setting up an air entrainment mask to deliver 40% oxygen to a patient. If the therapist runs the mask with 9 Liters of oxygen (per minute), how many Liters of air (per minute) are entrained? You must set up and solve a proportion that includes a word plan in your solution. Problem #2 A patient is wearing a 24% air entrainment mask running at 3 L/M (3 liters of oxygen per minute). What is the total flow of gas per minute being delivered? You must set up and solve a proportion that includes a word plan in your solution. Also, keep in mind that total flow will be the amount of air plus the amount of pure oxygen that is being added by the mask. Erie Community College Title III Grant Problem #3 A patient wearing a 35% air entrainment mask has its oxygen flow increased from 4 L/M to 8 L/M. a. Set up and solve a proportion (including a word plan) to find the total flow of gas per minute that was being delivered when the oxygen flow was 4 L/M. b. Set up and solve a proportion (including a word plan) to find the total flow of gas per minute that was being delivered when the oxygen flow is 8 L/M. c. What is the change in total flow? Problem #4 A respiratory therapist is setting up a 30% air entrainment mask at 6 L/M (the oxygen flow). Calculate the total flow of gas. You must set up and solve a proportion that includes a word plan in your solution. Use the following problem as an example to help you complete problems 5 and 6. A patient requires a total flow of 50 L/M from his oxygen mask which is set to deliver 40% oxygen. What should be the minimum oxygen flow set to meet the patient’s inspiratory flow rate demands? Round your answer to the nearest integer. Explanation: At 40%, the air:oxygen ratio is 3:1 (remember this means 3 parts air and 1 part pure oxygen, making the total flow 3parts + 1part = 4parts). Recall that other ratios are 3 6 9 12 equivalent to this simplified ratio: etc . The numerator and denominator can be 1 2 3 4 multiplied by any integer to obtain an equivalent ratio. Our goal is to find what number to multiply both numbers in the ratio by to achieve a total flow of 50 L/M. Let x = minimum oxygen flow set. 3x + x 50 (Remember the numbers in the ratio are 3 and 1) 4x 50 (Divide both sides by 4) x 12.4 Since the answer must be greater than 12.4, we must go up to the next integer. x= 13 L/min Erie Community College Title III Grant Problem #5 A patient requires a total flow of 72 L/M from his oxygen mask which is set to deliver 24% oxygen. What should be the minimum oxygen flow set to meet the patient’s inspiratory flow rate demands? Round your answer to the nearest integer. Problem #6 A patient requires a total flow of 62 L/M from his oxygen mask which is set to deliver 35% oxygen. What should be the minimum oxygen flow set to meet the patient’s inspiratory flow rate demands? Round your answer to the nearest integer. F. Student Resources (websites, books, technology, etc.) Textbook; Class notes (to review ratios and proportions) G. Faculty Resources (teacher notes, websites, books, technology, etc.) H. Suggested Grading Rubric Problems 1 - 6: 7.5 points each Neatness and Legibility: 5 points Total: 50 points Erie Community College Title III Grant Answer Key Problem 1: 3 x 1 9 air oxygen x = 27 L/min Problem #2: air oxygen 25 x 1 3 x = 75 L/min (this is the amount of air). To find the total flow, it must be added to the number of liters of oxygen that the mask is adding” 75 + 3 = 78L/min. Problem #3: a. air oxygen 5 x 1 4 x = 20 L/min ( amount of air). Total flow = 20 + 4 = 24 L/min. b. air oxygen 5 x 1 8 x = 40 L/min (amount of air). Total flow = 40 + 8 = 48 L/min. c. Change in total flow = 48 – 24 = 24 L/min. Problem #4: air oxygen 8 x 1 6 x = 48 L/min (the amount of air). Total flow = 48 + 6 = 54 L/min. Problem #5: Let x = minimum oxygen flow set. 25x + x 72 26x 72 x 2.77 x = 3 L/min Problem #6: Let x = minimum oxygen flow set. 5x + x 62 6x 62 x 10.33 x = 11 L/min Erie Community College Title III Grant Erie Community College Title III Grant