Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards
share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

PFT's

WillWallace PFT's

QuestionAnswer
TLC Normal total lung capacity 6000ml
VT Normal tidal volume 500 ml
VC normal vital capacity 4800
RV normal residual volume 1200
Volumes that cannot be directly measured in a PFT RV, FRC, TLC
Tests used for RV, FRC, and TLC Helium dilution, Nitrogen washout, body box (most accurate)
PFT Equipment for measuring volume water sealed spirometer (uses bell) bellows spirometer (most popular) dry rolling seal spirometer
Infection Control in PFT's standard precautions fluids-hand washing, gloves, barrier filters. Infectious disease- personal respirator or close fitting mask (N-95 for TB). safe disposal, sterilize or disinfect equip between patients.
Why PFT's identify and quantify changes in pulm function, epidemiological surveillance for pulm disease, assessment of post op risk, determine pulm disability, evaluate and quantify therapeutic effectiveness
Patient instructions for FVC effort dependent, careful instructions, be sure Pt understands and will cooperate, demonstrate, enthusiastic coaching, sitting standing ok, nose clips on or off ok, 3 tests, best 2 must be within 5% ( convert atps to btps)
ATPS to BTPS since ATPS can be 5 to 15% different that BTPS, adjustments must be made or test will be invalid.
FEV1 forced exp volume in 1 second, Normal is 4.2 L...(<80%=obstructive), measured as volume it is considered a flow. Used as a measure of general severity with airway obstruction
FEV2 forced exp volume in 2 seconds, normal is 4.6L
FEV3 forced exp volume in 3 seconds 4.8L
PEFR Peak exp flow rate, steepest point on curve on the "FLOOP", normal is 9.5L/sec (best identified on a flow-volume loop
FEF200-1200 forced exp press between 200 and 1200, normal 8.5ml/second, measures large airway flow
FEF25-75 forced exp flow between 25 and 75, normal is 4.5L/second, measures small airways
Measuring RV Residual Volume, normal 1200, like the FRC & TLC it cannot be directly measured. alternative tests are, 1.Body box 2. Helium dilution 3. Nitrogen washout
Body Box best method to measure RV, uses Boyles Law to calc RV, larger values because more accurate information
PFT Contra-indications hemoptysis, pneumothorax, cardio problems, thoracic, abdominal or cerebral aneurysm, recent eye surgery, acute disease that may cause nausea or vomiting, recent ab or chest surgery
FVC Validity/Reliability 3 acceptable tests must be given, best 2 should not vary by more than 5%, no cough, swallow or disruptions, smooth, continuous and complete, exhalation must be a minimum of 6 seconds
M V V Max voluntary ventilation, normal is 160L/min, tested with Spirogram, fast and hard for at least 12 seconds, 2x-use best results, tests for strength of muscles, flow and capacity, tested pre-op/ make sure patient can get of vent post op
PFT Severity normal 80 - 120, moderate 50-64, very severe <35
Obstructive severity check FEV1 & FEV1%
Restrictive Severity check FVC, TLC & VC
DLCO Diffusion of Lung Carbon Monoxide, normal is 40ml/min/mmHg, 0.3%CO & 10% He in air held in a single breath for 10 seconds.
Restrictive Disease ↓ volumes & capacities, affects lung parenchyma and thoracic pump, ↓ inspiration, ↓CL, more vertical slope on PFT tracing than obstructive, restriction+diffusion=fibrosis
Obstructive Disease ↓ Flows, ↑ CL, flatter curve on PFT tracing, affects airways, obstruction+diffusion=emphysema
FVC Forced Vital Capacity, normal is 480 ml
FEV1% FEV1/FVC, normal is 75 to 85 % (<70%=obstruction)
VC/TLC% VC is normally 80% of TLC
Spirometery Value Factors height, age, gender, ethnicity, sometimes for extreme weight and altitude (may be reduced 12 to 15 % for non-white)
FVC Tracings obstructive curve is flatter, restrictive curve is more vertical
Conditions that ↓ DLCO ↓ DLCO is associated with emphysema , Fibrosis, restrictive diseases, carbohemoglobin polycythemia, CHF, anemia, pulm embolism, exercise
Airway Obstruction Tests FEF200-1200, normal is 8.5 L/sec, <80%=large airway disease. FEF25-75, normal is 4.5 L/sec,<80%=small airway disease. (FRC or RV >120%=airtrapping)
Patient Effort Patient efforts insures validity and reliability of tests. Tests that are not valid or reliable, can lead to misdiagnoses, mistreatments and poor outcomes
Reversibility of airway obstruction before and after treatment studies, FEV1 >15% indicates effective treatments
PFT categories (test types) lung vol and cap, flow rates through airways, ability of lungs to diffuse gases (DL)
Nitrogen washout test open circuit (non-re breather), exhaled gas measured for N2, Patient breaths until little N2 remains, 2-5 mins normal, COPD longer (perforated ear drum will scew test)
Helium Dilution test measures RV,FRC,TLC...closed circuit, helium and O2, CO2 is absorbed by soda lime and )2 is added, Pt breaths until gas concentration is equalized 3-5 mins (20 mins in copd)
Fibrosis restriction + diffusion
bronchoprovocation testing methocholine induced asthma attack, positive response is FEV1 falls more than 20%, reversed with svn or mdi treatment
Created by: annabannana