res 131 l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
RES 131 PowerPoint Presentation
Download Presentation
RES 131

Loading in 2 Seconds...

play fullscreen
1 / 52

RES 131 - PowerPoint PPT Presentation


  • 203 Views
  • Uploaded on

RES 131. Pulmonary Function Testing. Laboratory Instrumentation. TWO TYPES OF SPIROMETERS AVAILIBLE IN THE PFT LAB. VOLUME-DISPLACING Sometimes known as “volume collecting” FLOW-SENSING. VOLUME-DISPLACING SPIROMETERS. COLLECTS EXHALED AIR ACTS AS A RESEVOIR FOR INHALED AIR.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'RES 131' - jaden


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
res 131

RES 131

Pulmonary Function Testing

laboratory instrumentation
Laboratory Instrumentation
  • TWO TYPES OF SPIROMETERS AVAILIBLE IN THE PFT LAB.
    • VOLUME-DISPLACING
      • Sometimes known as “volume collecting”
    • FLOW-SENSING
volume displacing spirometers
VOLUME-DISPLACING SPIROMETERS
  • COLLECTS EXHALED AIR
  • ACTS AS A RESEVOIR FOR INHALED AIR.
water seal spirometer
WATER SEAL SPIROMETER
  • CONSISTS OF THREE CYLINDERS
    • ONE CYLINDER WITH OPENING ON TOP
    • SECOND CYLINDER WITH OPENING ON BOTTOM
    • THIRD CYLINDER BETWEEN 1ST AND 2ND WITH OPENING ON BOTTOM
bellows spirometer
BELLOWS SPIROMETER
  • USUALLY CONSISTS OF :
    • SOFT FLEXIBLE BELLOWS
    • LATEX OR RUBBER
    • RIGID OR SEMI-RIGID PANELS ON EITHER SIDE OF THE BELLOWS
dry rolling seal
DRY ROLLING SEAL
  • COMPRISED OF A PISTON IN A CYLINDER
    • USES A SOFT SILICONE BASED ELASTIC MATERIAL AS A SEALING COMPONENT
    • OLD SYSTEMS USED A LEATHER ROLLING SEAL
diaphragm spirometer
DIAPHRAGM SPIROMETER
  • CONSISTS OF:
    • HOUSING
    • UPPER AND LOWER
    • DIAPHRAGM
    • PUSHER PLATE
volume displacement spirometer s
VOLUME DISPLACEMENT SPIROMETER'S
  • GENERALLY, BEFORE TESTING STARTS, THESE SPIROMETER'S ARE EMPTY
  • SOME TYPES ALLOW PRESETTING OR FILLING BEFORE TESTING
desirable characteristics
DESIRABLE CHARACTERISTICS
  • DIRECTLY MEASURE VOLUME
  • LOW COST
  • EASE OF OPERATION
  • WATER-SEAL SPIROMETER IS CONSIDERED TO BE THE “GOLD STANDARD”
undesirable characteristics
UNDESIRABLE CHARACTERISTICS
  • SOME VERY LARGE AND BULKY
  • LESS PORTABLE
  • WATER MUST BE CHANGED
  • LEAKS
  • MANUAL CALCULATION REQUIRED IF NO MICROPROCESSOR
flow sensing spirometer s
FLOW-SENSING SPIROMETER'S
  • VOLUME IS CALCULATED BY MULTIPLYING:
    • FLOW BY TIME
    • THIS IS KNOWN AS “INTEGRATION”
    • REQUIRES A COMPUTER OR MICROPROCESSOR
four types of flow sensing spirometer s
FOUR TYPES OF FLOW SENSING SPIROMETER'S
  • PNEUMOTACHOGRAPH
  • HOT-WIRE ANEMOMETER
  • TURBINE DEVICE
  • VORTEX DEVICE
pneumotachograph
PNEUMOTACHOGRAPH
  • ALSO KNOWN AS “DIFFERENTIAL PRESSURE DEVICE”
  • TUBE WITH FIXED RESISTANCE
  • CONTAINS A BUNDLE OF CAPILLARY TUBES OR FINE MESH SCREEN(S)
pneumotachograph19
PNEUMOTACHOGRAPH
  • ACCURACY BASED ON FIXED RESISTANCE
  • CHANGES IN RESISTANCE AFFECT ACCURACY
    • WATER VAPOR
    • SECRETIONS
  • MANY ARE HEATED TO PREVENT CONDENSATION
hot wire anemometer
HOT-WIRE ANEMOMETER
  • FINE WIRE IN CENTER OF TUBE
  • AIR MOVING THROUGH THE TUBE COOLS THE WIRE
  • ELECTRICAL CURRENT IS PASSED THROUGH WIRE TO MAINTAIN TEMPERATURE
  • CURRENT NEEDED TO MAINTAIN TEMP IS MEASURED
hot wire anemometer21
HOT-WIRE ANEMOMETER
  • UNABLE TO MEASURE TURBULENT FLOWS ACCURATELY
  • LONG TUBE REQUIRED TO CREATE LAMINAR FLOW
  • FRAGILE
turbine device
TURBINE DEVICE
  • TURBINE INCREASES SPEED WITH INCREASING FLOW
  • REVOLUTIONS ARE MEASURED
  • INERTIA CREATES INACCURACY
turbine device24
TURBINE DEVICE
  • NOT AFFECTED BY:
  • TURBULENT FLOW
  • MOISTURE
  • GAS COMPOSITION
vortex device
VORTEX DEVICE
  • STRUTS IN AIRFLOW CAUSE TURBULENCE RESULTING IN A VORTEX
  • VORTEXES ARE COUNTED
vortex device27
VORTEX DEVICE
  • NOT SENSITIVE ENOUGH TO MEASURE LOW FLOWS
flow sensing spirometers
Flow Sensing Spirometers
  • DESIRABLE CHARACTERISTICS
    • SMALLER AND MORE PORTABLE
    • COMPUTERIZED, NO MANUAL CALCULATIONS
    • MANY PROVIDE QUICK REFERENCE VALUES
    • CAN MEASURE BI-DIRECTIONAL FLOW
flow sensing spirometers29
Flow Sensing Spirometers
  • UNDESIRABLE CHARACTERISTICS
    • MORE KNOWLEDGE REQUIRE TO OPERATE COMPUTER
    • FREQUENT AND CAREFUL CALIBRATION
    • MOISTURE AND SECRETIONS CAUSE INACCURACY
    • GAS COMPOSITION CAN AFFECT RESULTS
    • MAY NOT SENSE LOW FLOWS
choosing a spirometer
CHOOSING A SPIROMETER
  • RECOMMENDATIONS FOR SPIROMETER'S ARE PUBLISHED BY THE AMERICAN THORACIC SOCIETY
  • PUBLISHED IN 1979, 1987 AND THE LATEST IN 1995
spirometer s for forced expiratory maneuvers
SPIROMETER'S FOR FORCED EXPIRATORY MANEUVERS
  • ABLE TO MEASURE VOLUMES OF AT LEAST 8 LITERS
  • FLOWRATES (INSPIRATORY AND EXPIRATORY) BETWEEN 0 AND 12 LITERS PER SECOND
spirometer s for forced expiratory maneuvers32
SPIROMETER'S FOR FORCED EXPIRATORY MANEUVERS
  • ABLE TO COLLECT OR MEASURE VOLUMES FOR 15 SECONDS
  • IF THE SPIROMETER IS USED TO MEASURE THE FEV1, THE BACK EXTRAPOLATION METHOD SHOULD BE USED
spirometry displays
SPIROMETRY DISPLAYS
  • TWO WAYS TO DISPLAY THE SPIROGRAM
  • VOLUME-TIME
  • FLOW-VOLUME
volume time display
VOLUME-TIME DISPLAY
  • VOLUME IS DISPLAYED ON THE Y AXIS (VERTICAL)
  • TIME IS DISPLAYED ON THE X AXIS (HORIZONTAL)
volume time display35
VOLUME-TIME DISPLAY
  • USEFUL IN EVALUATING THE LENGTH OF A TEST MANEUVER
  • ALLOWS ASSESSMENT OF VOLUME PLATEAU DURING THE TERMINAL PORTION OF THE TRIAL
flow volume display
FLOW-VOLUME DISPLAY
  • FLOW IS DISPLAYED ON THE Y AXIS (VERTICAL)
  • VOLUME IS DISPLAYED ON THE X AXIS (HORIZONTAL)
flow volume display38
FLOW VOLUME DISPLAY
  • MOST USEFUL IN EVALUATING THE START OF TEST
  • TYPICALLY, THE GRAPH IS SCALED SO THAT THE FLOW REPRESENTATION IS TWICE THAT OF THE VOLUME
calibration of pulmonary function instrumentation
CALIBRATION OF PULMONARY FUNCTION INSTRUMENTATION
  • Without a conscientiously applied calibration program, pulmonary function instruments may generate erroneous information
calibration
CALIBRATION
  • Calibration of volume collecting and flow sensing SPIROMETER'S require the use of a calibration syringe
calibration of volume collecting spirometer s
Calibration of volume collecting SPIROMETER'S
  • Patient testing tubing should be attached
  • Inject the entire calibration syringe volume
  • Observe the pen or graphic display
calibration of volume collecting spirometer s43
Calibration of volume collecting SPIROMETER'S
  • If the display or line does not travel in a straight line, there is a leak
  • If no leak is present, the indicated volume should be equal the volume of the calibration syringe within +/-3%
calibration of volume collecting spirometer s45
Calibration of volume collecting SPIROMETER'S
  • Calculation of acceptable calibration error
    • Multiply the syringe volume by 3% (.03)
    • 3.0 x .03 = .09
    • Add and subtract the calculated value from the known value
    • 3.0 L + .09 = 3.09 L
    • 3.0 L - .09 = 2.91 L
calibration of flow sensing spirometer s
Calibration of flow- sensing SPIROMETER'S
  • This type of spirometer of ten has a menu option for calibration
  • At least one injection from the calibration syringe should be with a reported value within +/- 3%
  • Usually several injections are completed
calibration of flow sensing spirometer s47
Calibration of flow- sensing SPIROMETER'S
  • ATS recommends varying the flow rate of the injections
  • Once at approx. 3 L/sec (1 second)
  • Once at approx. .05 L/sec (6 seconds)
  • Once at a rate between the previous two
calibration48
Calibration
  • If either type of spirometer cannot meet the accuracy standards, the spirometer may not be used.
  • Calibration must be completed at least daily or whenever accuracy is questioned
calibration49
Calibration
  • ATS standards require the documentation of the calibration
  • A log book should be kept, documenting the calibration values obtained
quality control
Quality Control
  • Activities used to maintain Quality
    • Laboratory Standards
      • Quarterly testing of known subjects with stable pulmonary conditions
    • Recorder time sweep
      • Check the accuracy of the recorder by stop watch
quality control51
Quality Control
  • Activities used to maintain Quality
    • Check the accuracy of the spirometer over the entire measurable range
    • Develop and maintain a procedure manual outlining testing techniques as well as calibration procedures
quality control52
Quality Control
  • Activities used to maintain Quality
    • Technician monitoring and feedback
      • Development of an objective system for evaluation of Technician performance