Class 5_Med Gases_BB_F 2024.pptx

MEDICAL GASES Hess Chapters 13 & Please Submit Your “Tank Duration Worksheet”  Review CYLINDER SIZES COLOR CODES Pressurized Cylinders Liquid Gas Cylinders  Review Safety systems were designed by the Compressed Gas Association to: a) Prevent the delivery of the wrong g...

MEDICAL GASES Hess Chapters 13 & Please Submit Your “Tank Duration Worksheet”  Review CYLINDER SIZES COLOR CODES Pressurized Cylinders Liquid Gas Cylinders  Review Safety systems were designed by the Compressed Gas Association to: a) Prevent the delivery of the wrong gas having different connections. b) Ensure that tanks are stored properly. c) Ensure that tanks are mark with the proper label. d) Allow safe transport across state lines.  Review Which of the following tank colors correctly identifies the gas? I. Oxygen – Green II. Air – Green/yellow III. Heliox – Brown/yellow IV. He/O2 – Brown/green a. Only I is correct b. I and IV are correct. c. II and III are correct. d. I, II, and IV are correct.  Review Which of the following statements concerning working and service pressures is/are correct? I. Both the working pressure and service pressure are 2200 psig. II. Service pressure is 2200, working pressure is 50 psig. III. Working pressure is 2200 psig. IV. Service pressure is 50 psig. V. Service pressure is 2015. a. Only II is correct. b. Only I is correct. c. I is correct, but with a reducing valve, IV is also correct.  Review Which of the following statements is true regarding the markings on an oxygen tank? a. All tanks must be inspected every 5 years and stamped accordingly. b. It is not necessary for a tank to have a D.O.T. regulation stamped on it. c. A tank may be approved for 3000 psig if tested for this limit and stamped accordingly. d. A “star” next to the test date indicates that the tank need not be test for 10 years.  Review The Diameter Index Safety System was designed for a low-pressure system. What pressure is common in hospital settings? a. 200 psig b. 2015 psig c. 20 psig d. 50 psig  Review You should always wash your hands: I. After treating a C-Diff patient. II. Anytime your hands are visibly soiled. III. After treating every patient. IV. Before entering any patient’s room. a. I and II are correct. b. I and III are correct. c. I, II, and IV are correct. d. II and IV are correct.  Review A patient is suspected to have TB, but no positive test results have been confirmed. You have been properly fitted with a N-95 mask. Which of the following statements is false concerning this case? a. TB is an airborne precaution risk. b. You must wear your N-95 mask when entering the room. c. It is not required to wear a N-95 mask until the patient has tested positive. d. The patient should be placed in a negative- pressure room.  Review Which of the following statements is/are true? I. Disinfection is the reduction of pathogenic organisms. II. Disinfection and sterilization are both decontamination processes. III. Sterilization kills all micro-organisms, except for spores. IV. Pasteurization will kill all spores. a. All the above are true. b. I and III are correct. c. II, III, and IV are correct.  Review An excellent high-level disinfectant for disinfection/sterilization of bronchoscopy scopes and other respiratory equipment is: a. “Quats” b. Acetic Acid c. Alcohol wipes d. Glutaraldehyde  Liquid O2 Duration Formula Liquid O2 expands 860 times to become gaseous O2. Weight 2.5 lbs per liquid liter. Exa: 3.50 lbs @ 4L/min. 3.50 lbs x 860 = 1204 liters  Liquid O2 Duration Formula 1204 liters 4 L/M 301 minutes or 5.02 hour (5hr 1 min) 60 min x.02 = 1.2 minutes Exa. 2: 1720 liters remaining and 5 LPM flow. How long will it last?  Review Safety Indexed Connector Systems MEDICAL GAS PIPING SYSTEMS Reducing Valves Characteristics of Medical Gases Review Oxygen (02) Production Maneuvering Large Medical Gas Cylinders Cracking the Cylinder Attaching a Reducing Valve/ Regulator  Bourdon Gauge (Flowmeter) May also be referred to as a fixed orifice flowmeter. This flowmeter is not a true flowmeter, but rather a pressure gauge calibrated to measure flow. Bourdon Gauge Flowmeter Bourdon Gauge Flowmeter Bourdon Gauge & Flowmeter  Bourdon Gauge Flowmeter These flowmeters are small and quite compact. They have an advantage in that they will operate in any position. This has definite advantages in a transport situation. The accuracy of the flowmeter is dependent upon the size of the outlet, but many medical grade gauges are Intentionally Left Blank  Thorpe Tube Flowmeters Thorpe tube flowmeters employ a Thorpe tube in their design. A Thorpe tube is a tapered tube with a small end at the bottom and a large end at the top. This V-shaped tube provides a variable orifice. The internal diameter of the tube varies from the bottom to the top, increasing in area toward the top.  Thorpe Tube Flowmeters A float is suspended in the tube by the flow of gas. In oxygen and air flowmeters, the float is typically a small diameter steel ball. The ball or float remains suspended as a result of a pressure differential between the top and bottom of the float. Thorpe Tube Flowmeters  Thorpe Tube Flowmeters Thorpe tube flowmeters can be classified into two general categories: (1) uncompensated, and (2) back pressure compensated (more commonly just called compensated). The placement of the needle valve in the flowmeter design determines whether it is uncompensated or compensated.  Uncompensated Thorpe Tube Flowmeters If one were to partially obstruct the outlet of the flowmeter, the pressure inside the Thorpe tube would increase due to the increased resistance. It is possible, in the face of back pressure distal to the needle valve, to deliver flows higher than indicated by the suspension of the float.  Back Pressure Compensated Flowmeter If one were to totally occlude the outlet, the pressure distal to the needle valve would be equal to the line pressure of 50 psi and the float would not be suspended, indicating zero flow. Uncompensated / Compensated Flowmeter Intentionally Left Blank  Flow Restrictor Consists solely of a fixed orifice, calibrated to deliver a specific flow at a constant pressure (50 psig). The operation of the flow restrictor is based on the principle of flow resistance.  GAS LAWS Ch 6 Several laws help define the relationship among gas pressure, temperature, mass, and volume. Intentionally Left Blank  Properties of Gases Gases share many of the same properties as liquids. Specifically, gases exert pressure, are capable of flow, and exhibit the property of viscosity. Unlike liquids, gases are readily compressed and expanded and fill the spaces available to them by diffusion.  Kinetic Activity of Gases Velocity of gas molecules is directly proportional to temperature. As gas is warmed its kinetic activity increases, its molecular collisions increase, and its pressure rises. When gas is cooled the molecular activity decreases and the pressure drops.  Gas Variables Pressure – intensity of force applied to the parcel of gas (force/area) Volume – 3D space occupied by the parcel of gas Mass – quantity of gas in the parcel, measured in mass units Density – mass/volume Temperature – measure of average kinetic energy of the gas  The Pressure-Volume Relationship: Boyle's Law Robert Boyle (1627-1691) Studied the relationship between the pressure exerted on a gas and the resulting volume of the gas. He utilized a simple 'J' shaped tube and used mercury to apply pressure to a gas:  Robert Boyle – Boyle’s Law He found that the volume of a gas decreased as the pressure was increased. Doubling the pressure caused the gas to decrease to one- half its original volume. Boyle's Law  The Temperature-Volume Relationship: Charles's Law The relationship between gas volume and temperature was discovered in 1787 by Jacques Charles (1746-1823). The volume of a fixed quantity of gas at constant pressure increases linearly with temperature. The line could be extrapolated to predict that gases would have zero volume at a temperature of -273.15°C (however, all gases liquefy or solidify before this low  Charles' Law If the temperature of a fixed mass of gas is increased and the volume remains constant, then the pressure of the gas will increase.  Gas Laws Charles Law Temperature and Volume Pressure is Constant Charles’ Law Summary Temperature and Volume are Directly proportional (if pressure is constant) (Volume)/(Temperature) = Constant Value  KELVIN SCALE In 1848 William Thomson (Lord Kelvin) proposed an absolute temperature scale for which 0°K equals -273.15°C In terms of the Kelvin scale, Charles's Law can be restated as: The volume of a fixed amount of gas maintained at constant pressure is directly proportional to its absolute temperature  Ideal Gas Law Equation of State Relationship between the variables that describe a gas, could be a parcel of air, or the entire atmosphere  Ideal Gas Law Relationship when P, V, and T may all be changing Combination of Boyle’s Law and Charles’ Law  Measuring Atmospheric Pressure At sea level the average atmospheric pressure will support a column of mercury 76 cm (760 mm) or 29.9 inches high.  Torricelli Evangelista Torricelli (Italian:1608– 1647) was a physicist and mathematician, best known for his invention of the barometer. As RT’s we use the term Torr interchangeably with mmHg (millimeters of mercury).  PRESSURE Pressure can be measured in: atmosphere (atm) millimeters of mercury (mmHg) (torr) after Torricelli, the inventor of the mercury barometer (1643) 1 atm = 760 mmHg = 760 torr  Dalton’s Law of Partial Pressures Every gas in a mixture of gases exerts its own partial pressure independently of the others. The pressure of a single gas in a mixture is known as the 'partial pressure'.  PRESSURE As an example, air consists of about 21% 02 and 78% N2. Assuming a normal atmospheric pressure of 760 torr, you compute the individual partial pressures as follows: partial pressure fractional concentration x total pressure Po2 149.73 =.21 (21%) FiO2 X 760 Pb FiO2 (Fraction of inspired Oxygen) 47mmHg = water vapor  TEMPERATURE A physical property of matter that determines the direction of heat flow. Measured on three scales. Fahrenheit o F Celsius o C Kelvin K o F = (1.8 oC) + 32 o C = (oF - 32)/1.8 K = oC + 273.15  TEMPERATURE If you don’t need an exact answer, here’s a shortcut… C0 to F0 (Temperature in Celsius) x 2 – 10% + 32 = Temperature in Fahrenheit F0 to C0 ((Temperature in Fahrenheit) – 30) /2 + 10% = Temperature in Celsius  Critical Temperature and Pressure For every liquid there is a temperature above which the kinetic activity of its molecules is so great that the attractive forces cannot keep them in a liquid state. This temperature is called the critical temperature.  Critical Point The critical temperature is the highest temperature at which a substance can exist as a liquid. The pressure needed to maintain equilibrium between the liquid and gas phases of a substance at this critical temperature is the critical pressure. Together, the critical temperature and pressure represent the critical point of a substance.  Liquefied Gases Filling Density is the ratio between the weight of the liquid gas put into the cylinder and the weight of water the cylinder could contain if full. Filling Density for CO2 is 68%. This allows the manufacturer to fill a cylinder with liquid CO2 up to 68% of the weight of water that a full cylinder could hold.  Review Lecture notes Hess CH 12 & 14 Work sheet Practice Cylinder Duration formula Work sheet Exam  Review Tank Duration Worksheet Study Guide