week 3

Question 1

what is the formula to find the % predicted

Answer 1

(actual/predicted) x 100=% predicted

Question 2

during PFT reports what are the 3 values reported

Answer 2

1. actual-what the pt performed
   2.predicted-what the pt should have performed based on Age,height,sex, race,weight
   3.%predicted

Question 3

what are the 3 main categories of PFT

Answer 3

1. dynamic flow rates of gases through airways
   -how well air is moving in/out of lungs
2. lung and volume and capacities
   -how much air the lungs can hold and how much air is left after exhaling

3.diffusion capacity

Question 4

what are the two catergories of pulmonary disease

Answer 4

1. obstructive- (flow)increased airway resistance
2. restrictive(volume)decrease in either lung compliance or lung volume or both

Question 5

what is compliance

Answer 5

how easily the lungs expand when we breath in
-volume of gas that can be inspired per the amount of inspiratory effort

C=change in volume/change in pressure

-restrictive lung disease-decreased compliance

Question 6

what is spirometry

Answer 6

measures how well lungs are functioning in terms of their ability to move air in/out
-measures:
FVC,FEV1,other forced expiratory flow, MVV

Question 7

define what body plethysmography (body box) is

Answer 7

-measure the FRC-volume in the lungs when the muscles of respiratory are relaxed and TLC
-pt is place in a sealed chamber the size of a small telephone booth with a single mouth piece

Question 7

define tidal volume

Answer 7

-volume of air moved during quiet breathing
-Normal: 500-700mL, average 500mL
-Normal in obstructive & restrictive disease,not valid indicator of lung disease

Question 8

define minute ventilation

Answer 8

(VE) is the volume of gas expired over 1 minute

VE=Vt x RR

Question 9

explain vital capacity

Answer 9

-(VC) is measured after the person has taken the deepest possible breath and exhaled as much as possible
-overall lung capacity
-to obtain a good VC= proper coaching

Question 10

what are the 3 key phases of the FVC maneuver

Answer 10

exaggerated body language
1.maximal inspiratory effort or breath
2.initial expiratory blast
3.forceful emptying of the lungs

Question 11

explain the two primary ways to measure VC

Answer 11

Inspiratory
-VC measured during inspiration pt exhales maximally, inhaled as deeply as possible, the volume of maximal inspiration is VC

expiratory
-VC during expiratory pt inhales maximally
then exhales maximally taking all the time necessary to exhale completely, volume is SVC

Question 12

define FVC

Answer 12

-most common test of pulmonary mechanics

-many measurements are made while pt is performing FVC maneuver

-FVC is an effort-depended maneuver requiring careful pt instruction and cooperation

-3 acceptable FVC

Question 13

is FVC decreased or increased in restrictive disease

Answer 13

decreased

Question 14

what are some common causes of decreased FVC in restrictive lung disease

Answer 14

-pulmonary fibrosis
*dust/toxin/drugs/radiation

-congestion of pulmonary blood flow
*pneumonia/pulmonary blood flow

-space occupying lesion
*tumors/pleural effusion

-neuromuscular disorders
*myasthenia gravis,guillain-barre

-chest deformities
* scoliosis/kyphoscoliosis

-obesity or pregnancy

Question 15

what does FVC measure

Answer 15

-FEV1
-FEV1/FVC
-FEF200-1200
-FEF25-75
-PEFR

Question 16

define what MIP/NIF

Answer 16

1. the value represents the maximum of negative pressure a pt can generate during inspiration
2. measures with a manometer which connects to ETT or mouthpiece if pt is not intubated

3.measures the strength of respiratory muscles (diaphragm other muscles involved in inspiratory)are

Question 17

what is the normal MIP/NIF

Answer 17

-50cmH2O-100cmH20

-20cmH2O is critical threshold

Question 18

what value of MIP/NIF is considered bad

Answer 18

less negative than -20cmH20 (closer to 0)
inadequate muscle strength

Question 19

define MEP

Answer 19

-assess the strength of respiratory muscles (exhalation muscles)

-measured with aneroid manometer via ett or mouth piece

Question 20

what is considered a critical value for MEP

Answer 20

less than 40cmH20
-pt not able to generate this amount not able to maintain spontaneous ventilation or secretion clearance
-mechanical ventilation necessary

Question 20

normal values for MEP

Answer 20

80-100cmH20

Question 21

define what the flow volume loop is

Answer 21

displays the volumes and flow rates measured during FVC
-restrictive: skinny and tall loop
-obstructive-short and wide loop

Question 22

explain MVV

Answer 22

12-15 second test
results reflect:
-pt effort
-function of respiratory muscles
-ability of chest wall to expand
-patency of airways

Question 23

results of PFT (TLC,FVC,RV)

Answer 23

-TLC,FVC,RV increase with obstructive -TLC,FVC,RV decreased with restrictive

Question 24

what is a normal TLC

Answer 24

6L

Question 25

what is a normal VC

Answer 25

4.8L in adults , vary with age,gender,height,and ethnicity *decreased volumes=restrictive *decreased VC= restrictive lung disease

Question 26

significance of results

Answer 26

-FEV1/FVC should be at least 70% normal FEV1= 4.7 L for 20 yrs -reduced with obstructive -normal with restrictive -MVV will be N or slightly reduced in restrictive -TLC less than 80% of predicted and FEV1/FVC is normal- restrictive disease

Question 27

rules to remeber

Answer 27

-restictive only: low volumes, VC or FVC -Obstructive only: low flows, FEV1, FEV1/FVC<70%

Question 28

severity FEV1 % predicted (obstruction)

Answer 28

normal: 80-120% mild: 70-79% mod:60-69% mod/sev:50-59% sev: 35-49% very sev: <35%

Question 29

causes of reduced thoracic compliance

Answer 29

-thoracic wall abnormalities-kyphoscoliosis -pressure exerted on thoracic cavity such as ascites or pregnancy

Question 30

causes of reduced lung compliance in restrictive lung diseases

Answer 30

- alveolar inflammation (pneumonia) -swelling (pulmonary edema) -scarring (pulmonary fibrosis)

Question 31

what are some restrictive lung diseases with decrease (FRC,FVC,IC,IRV) and normal FEV1/FVC

Answer 31

-pulmonary fibrosis -chest wall disease -pneumonia -neuromuscular disease -pleural disease -post surgical situations

Question 31

define pulmonary fibrosis

Answer 31

-alveolar wall inflammation resulting in fibrosis (fiberous tissue) vascular changes usually associated with pulmonary hypertension -increasing exertional dyspnea -pulmonary hypertension due to vascular changes

Question 31

how does a chest x ray look in pulmonary fibrosis

Answer 31

infiltrates are visible honeycombing pattern when advanced

Question 32

pft results of pulmonary fibrosis

Answer 32

spirometry:reduced VC lung volumes: reduced TLC- key indicator for pt with fibrosis

Question 33

define kyphoscoliosis

Answer 33

-posterior angulation of thorax and lateral curvature of spine (scoliosis) occur together -may result in hypoventilation,hypercapnia,pulmonary HTN -decreased compliance -results in reduced TLC and VC and restrictive disorder -diaphram impaired in severe cases

Question 34

what must you monitor in pt with neuromuscular diseases

Answer 34

ventilatory failure monitor -tidal volume -vital capacity -MIP/NIF *in values fall below initiate mechanical ventilation

Question 35

define myasthenia gravis

Answer 35

(mind to ground) -chronic disorder of the neuromuscular junction that interferes w/chemical transmission w,acetylcholine results in decending paralysis -gradual onset weakness -drooping of eyelids,double vision, dysphagia -shallow breathing -monitor:VT,VC.MIP/NIF -PFT:reduced volumes (FVC and sometimes Vt)

Question 36

define gullain barre disease

Answer 36

- rare autoimmune disorder of the peripheral nervous system - asending paralysis moves from ground-brain -febrile illness- viral -acute weakness, in legs , cyanosis -shallow breathing -spontaneous vent parameter: decrease Vt,VC, MIP/NIF -pft: reduced volumes (FVC,Vt) -treatment: oxygen,IS,IPPB,pulmonary hygiene, vent supportzsd

Question 37

restrictive severity TLC/FVC

Answer 37

N:80-100% Mild:60-79% Mod: 40-59% sev: <40%