11

THE ROLE OF FEVTHE ROLE OF FEV11/FEV/FEV66 IN THE IN THE

DETECTION OF AIRWAY OBSTRUCTIONDETECTION OF AIRWAY OBSTRUCTION

İlknur Başyiğitİlknur Başyiğit11, Haşim Boyacı, Haşim Boyacı11, , Serap Argun BarışSerap Argun Barış11,, Cavit Işık YavuzCavit Işık Yavuz22, Füsun Yıldız, Füsun Yıldız11

1 Kocaeli University Faculty of Medicine Chest Disease Department 2 Kocaeli University Faculty of Public Health Department

22

IntroductionIntroduction

Pulmonary function test has been used for the Pulmonary function test has been used for the diagnosis and follow up the treatment of airway diagnosis and follow up the treatment of airway diseases.diseases.

FEVFEV11/FVC < 70 % indicates airway obstruction./FVC < 70 % indicates airway obstruction.

33

IntroductionIntroduction

Because of the difficulties of performing FVC Because of the difficulties of performing FVC manuever, it is suggested that exhaled volume in the manuever, it is suggested that exhaled volume in the first 6 second of forced expirium (FEVfirst 6 second of forced expirium (FEV66) might be ) might be

used instead of FVC. used instead of FVC.

44

Aim

The aim of this study was to compare FEVThe aim of this study was to compare FEV11 // FEVFEV66

ratio which is offered as a new criteria with ratio which is offered as a new criteria with FEVFEV11/FVC which is accepted as a gold standard in /FVC which is accepted as a gold standard in

the detection of airway obstruction. the detection of airway obstruction.

55

Method

Prospective studyProspective study

Patients who were admitted to our pulmonary Patients who were admitted to our pulmonary function test (PFT) unitfunction test (PFT) unit during during a month were a month were prospectively evaluated. prospectively evaluated.

Mean age, gender, body mass index (BMI), the Mean age, gender, body mass index (BMI), the reason for PFT request and diagnosis were recorded. reason for PFT request and diagnosis were recorded.

PFT was performed PFT was performed using V max 20C spirometer. using V max 20C spirometer.

FEVFEV11, FVC, FEV, FVC, FEV11/FVC, FEV/FVC, FEV66 and FEV and FEV11/F/FEEVV6 6 valuesvalues

were determined. were determined.

66

ResultsResults

280 female, 290 male totally 570 patients were 280 female, 290 male totally 570 patients were included in the study.included in the study.

Mean age was 53Mean age was 53 ±± 15 yrs, 15 yrs,

BMI was 33.6BMI was 33.6 ±± 13.3 kg/m13.3 kg/m22..

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Table-1: Table-1: Demographic characteristicsDemographic characteristics

Age, yearAge, year 53 53 ±± 15 15

BMI, kg/mBMI, kg/m22 33.6 33.6 ±± 13.3 13.3

FVC, lFVC, l 2.82 2.82 ±± 0.97 0.97

FVC % predictiveFVC % predictive 84.5 84.5 ±± 21 21

FEVFEV1, 1, L L 2.07 2.07 ±± 87.7 87.7

FEVFEV1 1 % predictive% predictive 75 75 ±± 23 23

FEVFEV11 / FVC % / FVC % 73 73 ±± 15 15

FEF FEF 25-75, 25-75, ll 1.9 1.9 ±± 1.33 1.33

FEF FEF 25-75 25-75 % predictive% predictive 54 54 ±± 32 32

FEV FEV 6, 6, ll 2.71 2.71 ±± 0.96 0.96

FEVFEV11 / FEV / FEV 6 6 %% 75.4 75.4 ±± 13.5 13.5

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ResultsResults

The most common reasons for PFT requests were as The most common reasons for PFT requests were as follows;follows;

asthma in 103 asthma in 103

evaluation of dyspnea in 124evaluation of dyspnea in 124

preoperative evaluation in 108 preoperative evaluation in 108

COPD in 89 patientsCOPD in 89 patients

99

Table-2: Table-2: PFT resultsPFT results according to PFT requests according to PFT requests (Based on FEV(Based on FEV11/FVC)/FVC)

nn 00 11 22 33 44 TotalTotal

1.Asthma1.Asthma 103103 2222 3434 33 99 3535 103103

2.BHR2.BHR 2121 77 33 11 44 66 2121

3.COPD3.COPD 8989 11 4848 55 3131 44 8989

4.Dyspnea 4.Dyspnea 124124 3333 2828 2929 88 2626 124124

5.Cough5.Cough 5353 2727 66 33 22 1515 5353

6.Preop.6.Preop. 108108 3232 2121 2323 66 2626 108108

7.Others7.Others 7272 2727 88 1717 44 1616 7272

O:Normal, 1:Obstructive, 2:Restrictive, 3:Mixt, 4:Small airways disease

1010

Table-3Table-3:: PFT parameters according to PFT requestsPFT parameters according to PFT requests

nn FVCFVC FVC %FVC % FEVFEV11 FEVFEV11%% FEVFEV11/FVC/FVC

%%

FEVFEV66 FEVFEV11/FEV/FEV66

%%

AsthmaAsthma 103103 2.94 2.94 ±± 0.9 0.9 91 91 ±± 17 17 2.12 2.12 ±±0.750.75 79 79 ±± 19 19 73 73 ±± 10 10 2.86 2.86 ±± 0.9 0.9 75 75 ±± 9 9

BHRBHR 2121 2.91 2.91 ±± 0.9 0.9 83 83 ±± 16 16 2.28 2.28 ±±0.850.85 76 76 ±± 20 20 77 77 ±± 11 11 2.86 2.86 ±± 0.8 0.8 78 78 ±± 10 10

COPDCOPD 8989 2.83 2.83 ±± 0.87 0.87 77 77 ±± 22 22 1.5 1.5 ±± 0.67 0.67 51 51 ±± 20 20 52 52 ±± 13 13 2.51 2.51 ±± 0.8 0.8 58 58 ±± 12 12

DyspneaDyspnea 124124 2.76 2.76 ±± 1.03 1.03 83 83 ±± 22 22 2.1 2.1 ±± 0.9 0.9 76 76 ±± 22 22 76 76 ±± 13 13 2.7 2.7 ±± 1.02 1.02 79 79 ±± 12 12

CoughCough 5353 3.25 3.25 ±± 0.98 0.98 94 94 ±± 20 20 2 .65 2 .65 ±± 0.9 0.9 90 90 ±± 19 19 81 81 ±± 10 10 3.2 3.2 ±± 0.9 0.9 82 82 ±± 9 9

Preop.Preop. 108108 2.52 2.52 ±± 0.9 0.9 81 81 ±± 19 19 1.95 1.95 ±± 0.7 0.7 78 78 ±± 21 21 78 78 ±± 13 13 2.46 2.46 ±± 0.8 0.8 79 79 ±± 12 12

OthersOthers 7272 2.87 2.87 ±± 1.0 1.0 85 85 ±± 21 21 2.27 2.27 ±± 0.9 0.9 80 80 ±± 23 23 78 78 ±± 12 12 2.8 2.8 ±± 1.0 1.0 80 80 ±± 11 11

1111

Results

PPatients were divided into 2 groups according to their atients were divided into 2 groups according to their FEVFEV11 // FVC values as obstructive (FEVFVC values as obstructive (FEV11 // FVC <70%) FVC <70%)

and non-obstructive; and non-obstructive;

212 patients in the obstructive 212 patients in the obstructive

358 patients in the non-obstructive group. 358 patients in the non-obstructive group.

1212

Results

WWhen FEVhen FEV11 // FEVFEV6 6 value was considered,value was considered,

176 patients were determined as obstructive176 patients were determined as obstructive

394 as non-obstructive.394 as non-obstructive.

1313

Tablo-4: Tablo-4: Number of obstructive and non-obstructive Number of obstructive and non-obstructive cases according to FEVcases according to FEV11/FVC and FEV/FVC and FEV11/FEV/FEV66

FEVFEV11 / FEV / FEV66

ObstructiveObstructive Non-Non-obstructiveobstructive

TotalTotal

FEVFEV11 / FVC / FVC

ObstructiveObstructive 174174 3838 212212

Non-Non-obstructiveobstructive

22 356356 358358

TotalTotal 176176 394394 570570

1414

Graphic-1

0

50

100

150

200

250

300

350

400

FEV1/FVC FEV1/FEV6

Obstructive

Non-obstructive

1515

Results

FEVFEV1 1 / FEV/ FEV66 hadhad

sensitivity of 82.1%sensitivity of 82.1%

specificity of 99.4%specificity of 99.4%

positive predictive value of 98.9%positive predictive value of 98.9%

negative predictive value of 90.4%.negative predictive value of 90.4%.

1616

Results

Mean difference between FVC and FEVMean difference between FVC and FEV66

(FVC-FEV(FVC-FEV66) was found to be significantly higher in ) was found to be significantly higher in

obstructive patients compare to othersobstructive patients compare to others

23.423.4 ±± 23.5 ml (max:122 ml) vs. 23.5 ml (max:122 ml) vs.

3.33.3 ±± 14.7 ml (max: 114 ml), p=0.00014.7 ml (max: 114 ml), p=0.000

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Tablo-5:Tablo-5: FVC-FEVFVC-FEV6 6 inin obstructive and non-obstructive groups obstructive and non-obstructive groups

(FVC-FEV(FVC-FEV6 6 ) ml) mlObstructiveObstructive Non-obstructiveNon-obstructive

nn %% nn %%

0 ml0 ml 88 44 102102 2828

0-24 ml0-24 ml 125125 5959 249249 7070

25-49 ml 25-49 ml

5757 2727 66 1.71.7

50-74 ml50-74 ml 1313 66 00 00

75-100 ml75-100 ml 66 33 00 00

>100 ml>100 ml 33 11 11 0.30.3

TotalTotal 212212 100100 358358 100100

1818

Conclusion

It is suggested that FEVIt is suggested that FEV11 // FEVFEV6 6 ratio may not be as ratio may not be as

sensitive as FEVsensitive as FEV11 // FVC in the detection of airway FVC in the detection of airway

obstruction. obstruction.

Since FVC-FEVSince FVC-FEV66 found to be significantly higher in found to be significantly higher in

obstructive cases, diagnostic value of FEVobstructive cases, diagnostic value of FEV66 in this in this

subgroup is still controversial. subgroup is still controversial.