interpretation normal spirometry obstructive pattern restrictive pattern mixed pattern small airway...

Interpretation

Normal Spirometry Obstructive pattern Restrictive pattern Mixed pattern Small airway obstruction Non-specific ventilatory pattern Probably normal pattern Upper airway obstruction pattern Neuromuscular diseases

Normal Spirogram

All parameters are normal

Normal shape in VT and FV loop

A. Normal:A. Normal: both the FVC and the both the FVC and the FEVFEV11/VC ratio are normal./VC ratio are normal.

““KneeKnee””

Obstructive pattern

Obstructive pattern

The severity of the abnormality is graded:The severity of the abnormality is graded:

- % Pred FEV- % Pred FEV11 > 100 > 100 = = May be a physiological May be a physiological variantvariant

- % Pred FEV- % Pred FEV11 < 80 and > 70 < 80 and > 70 MildMild

- % Pred FEV- % Pred FEV11 < 70 and > 60 < 70 and > 60 ModerateModerate severesevere

--% Pred FEV% Pred FEV11 < 60 and > 50 < 60 and > 50 ModeratelyModerately

- % Pred FEV- % Pred FEV11 < 50 and > 35 < 50 and > 35 SevereSevere

- % Pred FEV- % Pred FEV11 < 35 < 35 Very severeVery severe

Severe obstructive pattern

Restrictive pattern

Restrictive pattern

The severity of the abnormality might be The severity of the abnormality might be graded as follows:graded as follows:

-- % Pred FVC < LLN and > 70 % Pred FVC < LLN and > 70 mildmild- - % Pred FVC < 70 and > 60% Pred FVC < 70 and > 60 ModerateModerate--% Pred FVC < 60 and > 50% Pred FVC < 60 and > 50 ModeratelyModerately

severesevere--% Pred FVC < 50 and > 34% Pred FVC < 50 and > 34 SevereSevere- - % Pred FVC < 34 % Pred FVC < 34 Very severeVery severe

Mixed pattern

Small airway obstruction

Early small airway obxEarly small airway obx

FV curve :upward concavityFV curve :upward concavity

FVC, FEV1, FEV1/FVC :NLFVC, FEV1, FEV1/FVC :NL FEF 25-75 ???FEF 25-75 ??? ATS states that FEF25-75% should not be used to

diagnose small airway disease or to assess respiratory impairment

Probably normal

Isolated decrease in FEF25-75

Isolated decrease in FEV1/FVC

Probably normal spirogramProbably normal spirogram

Only Only FEF 25-75 FEF 25-75 No small airway disease (ATS)No small airway disease (ATS)

Only Only FEV1/FVC FEV1/FVC

FEV1> 100% Probably NormalFEV1> 100% Probably Normal

FVC>100%FVC>100%

Nonspecific ventilatory pattern

Similar to restrictive pattern

Normal TLC, RV & DLco

Obesity Asthma COPD Normal variant

Upper airway obxUpper airway obx

Upper airway obstruction pattern

Indications for referral

FEV1/FVC less than %75 and FEV1 less than %80 FEV1/FVC more than %75 and FVC less than %80 Significant reduction across time Pulmonary symptoms or signs even with normal spirogram

Screening Spirometry

General health Occupational health screening

Screening Spirometry in General Healthy Population

Baseline spirogram in all at 20-25 Periodic spirogram depends on risk factors

such as smoking each 1-5 yrs.

Occupational screening spirogram In certain occupational exposures

Asbestos, silica, cadmium, cotton, coal, beryllium, wood dust,….

Usually each 1-2 yrs

Comparison of periodic spirogram Significant change in FEV1 or FVC

Cross-shift Week-to-week Year-to-year

Definition

Considerations in periodic spirogram Using:

Similar reference values Similar patient position Similar time Standard spirometer Standard technique

Change in spirometric indices over timeChange in spirometric indices over time

malemale femalefemale malemale femalefemale

30 ml/yr30 ml/yr 25 ml/yr25 ml/yr 25 ml/yr25 ml/yr 25 ml/yr25 ml/yr

FEV1FEV1 FVCFVC

NIOSHNIOSH : :

(0.85 .initial FEV1 or FVC) – (number of yr . 0.025)(0.85 .initial FEV1 or FVC) – (number of yr . 0.025)

(value on time 1 – value on time 2 / value on time 1) × 100

In an ongoing annual surveillance of asbestos workers, a 24 year old woman is found to have an FVC of 3.59 liters. Her previous FVC was 4.17 liters. What is your interpretation?

Absolute change: 4.17-3.59 = .58 liters She showed a loss of .58 liters.

Percent change: ((4.17-3.59)/4.17) x 100 = 13.9% She showed a loss of 13.9% in her FVC.

Further investigation recommended Further investigation recommended

for follow-up results iffor follow-up results if::

1. Decline in FEV1 or FVC > 15% in longitudinal screening. If the period is > 5 years, adjust for the decline due to aging (25 ml/year)

2. FEV1, FVC or FEV1/FVC < LLN at any time

3. >10% decline between pre and post shift screening

Case 1Case 1

A 71 yrs maleA 71 yrs male HeightHeight :175 , :175 ,weightweight :88 :88 FVC:45%FVC:45% FEV1: 31%FEV1: 31% FEV1/ FVC :53%FEV1/ FVC :53% FEF25-75 :15%FEF25-75 :15% TLC :142%TLC :142% very severe obxvery severe obx

Case 2Case 2

A 36 yrs femaleA 36 yrs female

HeightHeight :162 , :162 ,weightweight :83 :83

FVC:89%FVC:89%

FEV1: 94%FEV1: 94%

FEV1/ FVC :89%FEV1/ FVC :89%

FEF25-75 :131%FEF25-75 :131%

TLC :92%TLC :92%

normalnormal

Case 3Case 3

A 29 yrs femaleA 29 yrs female HeightHeight :165 , :165 ,weightweight :129 :129 FVC:78%FVC:78% FEV1: 79%FEV1: 79% FEV1/ FVC :86%FEV1/ FVC :86% FEF25-75 :85%FEF25-75 :85% TLC :82%TLC :82% non specific ventilatorynon specific ventilatory

Case 4Case 4

A 43 yrs femaleA 43 yrs female HeightHeight :61, :61,weightweight :167 :167 FVC:33%FVC:33% FEV1: 17%FEV1: 17% FEV1/ FVC :42%FEV1/ FVC :42% TLC :114%TLC :114% variable inthratoracicvariable inthratoracic obxobx

Case 5Case 5

A 30 yrs maleA 30 yrs male HeightHeight :186, :186,weightweight :68 :68 FVC:19%FVC:19% FEV1: 21%FEV1: 21% FEV1/ FVC :93%FEV1/ FVC :93% FEF25-75% :48%FEF25-75% :48% TLC :28%TLC :28% very severe restrictionvery severe restriction

Case 6Case 6

A 30 yrs maleA 30 yrs male

HeightHeight :175 , :175 ,weightweight :70 :70

FVC: 88%FVC: 88%

FEV1: 69%FEV1: 69%

FEV1/ FVC :66%FEV1/ FVC :66%

FEF25-75 :38%FEF25-75 :38%

VEXT : 90VEXT : 90

moderate obxmoderate obx

Case 7Case 7

A 29 yrs maleA 29 yrs male

HeightHeight :179 , :179 ,weightweight :83 :83

FVC: 95%FVC: 95%

FEV1: 84%FEV1: 84%

FEV1/ FVC :67%FEV1/ FVC :67%

FEF25-75 :51%FEF25-75 :51%

VEXT : 120VEXT : 120

Mild obxMild obx

Case 8Case 8

A 26 yrs maleA 26 yrs male

HeightHeight :177 , :177 ,weightweight :67 :67

FVC: 97%FVC: 97%

FEV1: 77%FEV1: 77%

FEV1/ FVC :66%FEV1/ FVC :66%

FEF25-75 :48%FEF25-75 :48%

VEXT : 60VEXT : 60

mild obxmild obx

Post bronchodilator spirometry(reversibility testing)

Short-acting inhaled drugs should not be used Short-acting inhaled drugs should not be used within within 4h4h of testing of testing

Long-acting should be stopped for Long-acting should be stopped for 12h12h prior test prior test Smoking should be avoided for Smoking should be avoided for ≥ 1h≥ 1h Salbutamol Salbutamol 400 µg400 µg (4 puffs) at 30 (4 puffs) at 30s intervalss intervals → ≥ → ≥

10 min and up to 15 min10 min and up to 15 min Ipratropium bromide Ipratropium bromide 160 µg160 µg (4 puffs)→30 min (4 puffs)→30 min

later

Positive reversibility testing

Percent change from baseline & absolute change in FEV1 and/or FVC :

>12% AND 200 CC

Other criteria include:

At least 20% increase in FEF25-75%

A 24 yrs maleA 24 yrs male HeightHeight :170 , :170 ,weightweight :82 :82

FVC:80%FVC:80% FEV1: 70%FEV1: 70% FEV1/ FVC :69%FEV1/ FVC :69% FEF25-75 :50%FEF25-75 :50%

pre post %change pre post %change

FVC 4 4.26 +7FVC 4 4.26 +7

FEV1 2.91 3.32 +14 FEV1 2.91 3.32 +14

FEV1/ FVC 72.8 77.9 +7 FEV1/ FVC 72.8 77.9 +7

FEF25-75 2.32 3.09 +31 FEF25-75 2.32 3.09 +31

Case Case

A 70 yrs male, A 70 yrs male, HeightHeight :172 , :172 ,weightweight :65 :65

pre %pred post %chgpre %pred post %chg

FVC 3.13 83 3.52 +12 FVC 3.13 83 3.52 +12

FEV1 2.02 70 2.49 +23FEV1 2.02 70 2.49 +23

FEV1/ FVC 64.5FEV1/ FVC 64.5

Case Case

A 28 yrs male , A 28 yrs male , HeightHeight :192 , :192 ,weightweight :92 :92

pre %pred post %chgpre %pred post %chg

FVC 5.68 95 5.81 +2FVC 5.68 95 5.81 +2

FEV1 4.02 81 4.28 +6FEV1 4.02 81 4.28 +6

FEV1/ FVC 68.2FEV1/ FVC 68.2

Thank you

Thank you