The Spirometry 1 Dr Mazen Qusaibaty MD, DIS / Head Pulmonary and Internist Department Ibnalnafisse Hospital Ministry of Syrian health – Dr Mazen Qusaibaty MD, DIS / Head Pulmonary and Internist Department Ibnalnafisse Hospital Ministry of Syrian health –

An average human breathes some 10 times per minute An average human breathes some 10 times per minute 600 times per hour 600 times per hour 14,400 times per day 14,400 times per day 5,256,000 times per year 5,256,000 times per year2

The Ventilation

Airways Alveoli Blood-Gas barrier Capillaries

The ventilation: The ventilation:  Is the movement of gas to the alveoli  FLOW

The ventilation  Flow 1.Alveolar pressure Changes 2.The pulmonary compliance 3.The pressure of elastic recoil 4.Resistance of airways

Action of Diaphragm

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VolumePressure

Pulmonary Expansion Pulmonary Expansion  Pulmonary Compliance Innate Elasticity (Elastic recoil pressure) Innate Elasticity (Elastic recoil pressure) 17

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19 Pulmonary fibrosisEmphysema

Diaphragm Innate Elasticity Pulmonary Compliance

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22 1.Alveolar pressure Changes 2.The pulmonary compliance 3.The pressure of elastic recoil 4.Resistance of airways

23 Total Ventilation = Volume exhaled per breath x RR (bpm)

The Diffusion across Blood-Gas interface

Airways Alveoli Gas Capillaries (Blood) Barrier: 1- 2 μm PA PV Alveolar-capillary Network O 2 and CO 2 passively diffuse across this barrier into plasma and red blood cells

The Diffusion across Blood-Gas interface barrier Gas Blood

D LCO or T LCO (diffusing capacity or transfer factor of the lung for carbon monoxide (CO) 27

28 Changes in the Partial Pressures of Oxygen and Carbon Dioxide

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Innate Elasticity Pulmonary Compliance  VentilationNormal Diffusion  Perfusion Pulmonary Fibrosis

Innate Elasticity  Pulmonary Compliance Ventilation  Diffusion+ - Perfusion Airway Diseases

Innate Elasticity  Pulmonary Compliance VentilationNormal Diffusion  Perfusion Alveolar Edema

33 Tidal volume (VT) The volume of air an individual is normally breathing in and out The volume of air an individual is normally breathing in and out

34 Tidal volume (VT) 500 mL

35 Inspiratory Reserve Volume (IRV) The maximum volume of air that can be inspired in addition to the tidal volume

36 Inspiratory Reserve Volume (IRV) IRV= 3.6 L

37 Expiratory Reserve Volume (ERV) The amount of additional air that can be puked out after the end expiratory level of normal breathing.

38 Residual Volume (RV) The amount of air left in the lungs after a maximal exhalation

39 Residual Volume (RV) The amount of air that is always in the lungs and can never be expired

40 Vital Capacity (VC) The amount of air that can be forced out of the lungs after a maximal inspiration

41 Vital Capacity (VC) VC = 4.6 L = IRV + Vt + ERV VC = 4.6 L = IRV + Vt (Inspiratory Capacity) + ERV

42 Forced Vital Capacity (FVC) The amount of air that can be maximally forced out speedily of the lungs after a maximal inspiration

43 Capacity (IC) Inspiratory Capacity (IC) The maximal volume that can be inspired following a normal expiration

44 Capacity (IC) Inspiratory Capacity (IC) IC IC = 4.1L

45 Forced Vital Capacity (FVC) FVC = 4.8 L

46 Functional Residual Capacity (FRC) The amount of air that stays in the lungs during normal breathing

47 Functional Residual Capacity (FRC) FRC = ERV + RV = 2.4 L FRC = ERV + RV = 2.4 L

Multiple-breath equilibrium helium dilution technique 48

49 Body plethysmograph Technique

50 Total Lung Capacity (TLC) The volume of air contained in the lung at the end of maximal inspiration

51 Total Lung Capacity (TLC) TLC = 6.0 L

52 Total Lung Capacity (TLC) TLC = TLC = IRV + Vt + ERV + RV

The predicted values of Lung volumes and Lung Capacities 53

Age Age Gender Gender Body Height Body Height Race Race

55 Spirometry

Spirometry is one of the most widely used lung function tests Spirometry is one of the most widely used lung function tests56

The basic values to interpret Spirometry are: The basic values to interpret Spirometry are:  FVC  FEV 1  FEV 1 /FVC ratio  FEF25–75% 57

Normal spirogram 58

59 FVC After taking a maximal inhalation FVC The FVC is the maximal amount of air that the patient can forcibly exhale

60 FVC The FVC also tends to decrease with increasing obstruction

61 FEV 1 The FEV 1 reflects the average flow rate during the first second of the forced vital capacity (FVC) maneuver The FEV 1 reflects the average flow rate during the first second of the forced vital capacity (FVC) maneuver

62 FEV 1 Assessment of airflow obstruction Assessment of airflow obstruction  airflow obstruction  FEV 1 airflow obstruction

63 FEV 1 It increases with successful treatment of airways obstruction It increases with successful treatment of airways obstruction

64 FEV 1 Degree of obstruction:   Mild   Moderate   Severe Asthma + COPD

65 (FEF 25-75% ) The forced expiratory flow (FEF 25-75% ) measured The forced expiratory flow (FEF 25-75% ) measured  During exhalation of 25 to 75% of the FVC

66 (FEF 25-75% ) More sensitive marker of mild small airway obstruction than the FEV1 More sensitive marker of mild small airway obstruction than the FEV1

FEV 1 /FVC ratio is considered as a ratio of Flow/Volume FEV 1 /FVC ratio is considered as a ratio of Flow/Volume67

68 FEV 1 / FVC ratio The FEV 1 /FVC ratio is:   The fraction or % of the Vital Capacity that can be exhaled in the first second

69 FEV 1 / FVC ratio Normal FEV 1 /FVC ratio > 70% to predicated value

70 FEV 1 / FVC ratio The FEV1/FVC ratio is not useful for gauging severity of disease The FEV1/FVC ratio is not useful for gauging severity of disease

71 Spirometry interpretation flow chart for the detection of obstruction

72 Spirometry interpretation flow chart for the detection of obstruction

73 Spirometry interpretation flow chart for the detection of obstruction

74 Spirometry interpretation flow chart for the detection of obstruction

75 Spirometry interpretation flow chart for the detection of obstruction

76 Spirometry interpretation flow chart for the detection of obstruction

77 Spirometry interpretation flow chart for the detection of restrictive lung disease

78 Spirometry interpretation flow chart for the detection of restrictive lung disease

79 Spirometry interpretation flow chart for the detection of restrictive lung disease

80 Spirometry interpretation flow chart for the detection of restrictive lung disease

81 Spirometry interpretation flow chart for the detection of restrictive lung disease

82 Characteristic Physiologic Changes Associated With Pulmonary Disorders

83 Mixed Disorders Restrictive Disorders Obstructive Disorders Measure Decreased Normal or increased DecreasedFEV1/FVC Decreased Decreased, normal, or increased DecreasedFEV1 DecreasedDecreased Decreased or normal FVC Decreased Normal or increased TLC Decreased, normal, or increased Decreased Normal or increased RV