C/ ??3 Some Typical Normal Values for Some Key Pulmonary Parameters FRC 2.6 L RV 1.5 L TLC 6.0 L VT...

download C/ ??3 Some Typical Normal Values for Some Key Pulmonary Parameters FRC 2.6 L RV 1.5 L TLC 6.0 L VT 500 ml FVC 4.5 L P FEV1.0 / FVC 75% Frequency 10-12/min

of 17

  • date post

    11-Mar-2018
  • Category

    Documents

  • view

    220
  • download

    6

Embed Size (px)

Transcript of C/ ??3 Some Typical Normal Values for Some Key Pulmonary Parameters FRC 2.6 L RV 1.5 L TLC 6.0 L VT...

  • 1

    Trachea(Generation #1)

    Primary Bronchi (Generation #2)

    Conducting Airways Generations 1-16

    2o Bronchi (Generation #3)

    Respiratory ZoneGenerations ~17-23

    Alveoli

    Respiratory Bronchioles

    O2

    CO2

    venous arterial

    PB=0

    PA0

    Alveolar AirO2 ~100 mmHgCO2 ~ 40 mmHg

    Expiration

    Ficks lawJ = DA (C/ X)

    LungChest Wall

    StuckTogether

    Lung

    Air leakPneumothoraxLung collapses& Chest expands

    Hemoglobin-O2 Binding Curve

    0 20 40 60 80 1000

    20

    40

    60

    80

    100

    0

    5

    10

    15

    20

    Venous

    Arterial

    CO2

    PaO2 (mm Hg)

    % H

    b Sa

    tura

    tion

    HbO

    2 content (ml O

    2 /dl)

  • 2

    PO2=100 mm Hg14 ml O2/dL

    PO2=100 mm Hg0.3 ml O2/dL

    O2

    O2

    PO2=100 mm Hg14 ml O2/dL

    PO2=100 mm Hg0.3 ml O2/dL dissolved20 ml O2/dL HB-O2

    O2

    O2

    VT

    Tota

    l Lun

    g C

    apac

    it y

    ExpiratoryReserve

    InspiratoryReserve

    FRC

    InspiratoryCapacity

    ResidualVolume

    VitalCapacity

    1 s

    FEV1.0

    VT

    Tota

    l Lun

    g C

    apac

    it y

    ExpiratoryReserve

    InspiratoryReserve

    FRC

    InspiratoryCapacity

    ResidualVolume

    VitalCapacity

    500 ml

    2.6 L

    1.5 L

    4.5 L

    ~6 L

    Forced Vital CapacityTLC

    FEV1.0 FVC

    1 secFEV1.0 = 4 LFVC = 5 L

    % = 80%

    RV

    TLC RV

    Exp

    irato

    ry F

    low

    Rat

    eLung Volume

    Flow-Volume Curves

    V. A Few Terms (for Your Convenience) Eupnia - Normal breathing. Apnea - cessation of respiration (at FRC). Apneusis - cessation of respiration (in the inspiratory phase). Apneustic breathing Apneusis interrupted by by periodic exhalation. Hyperpnea increased breathing (usual VT). Tachypnea increased frequency of respiration. Hyperventilation increased alveolar ventilation (PACO2 43 mm Hg). Atelectasis closed off alveoli, typically at end exhalation. Cheyne-Stokes Respiration Cycles of gradually increasing and decreasing VT. Dyspnea- Feeling of difficulty in breathing. Orthopnea- Discomfort in breathing unless standing or sitting upright. PIP - Intrapleural pressure (pressure in space between visceral and parietal plurae) PTP - Transpulmonary pressure (distending pressure of airway) PACO2 - Alveolar PCO2 (partial pressure of CO2). PaCO2 - arterial PCO2. PvCO2 - venous PCO2 PAO2 - Alveolar PO2 PaO2 - arterial PO2 PvO2 - venous PO2 PECO2 - PCO2 of exhaled air FECO2 fraction of exhaled air which is CO2 (i.e. A= Alveolar, a= arterial, v= venous, E = exhaled, I = inspired) VE Expired volume (liters) VE ventilation (liters/min) (V

    = dV/dt)

    VA Alveolar ventilation (liters/min)

    Q

    Blood Flow (liters/min)

  • 3

    Some Typical Normal Values for Some Key Pulmonary Parameters FRC 2.6 L RV 1.5 L TLC 6.0 L VT 500 ml FVC 4.5 L

    FEV1.0 / FVC >75% Frequency 10-12/min VA (norm) 5 0.5 L/min

    VE (norm) 7 0.7 L/min

    VE (max) 120-150 L/min

    Max. insp flow 7-10 L/sec

    Max. exp flow 6-9 L/sec Compliance 60-100 mL/cm H20 PAO2 100 mm Hg PaO2 (21% O2) 90-95 mm Hg PaO2 (100% O2) >500 mm Hg PaCO2 40 3 mm Hg Arterial pH 7.37-7.43 PvO2 40 mm Hg PvCO2 46 mm Hg [Hb] 14-15 g/dL

    ChestWall

    RecoilForce

    Lung Wall

    RecoilForce

    Normal

    Balance of Forces Determines FRCHookes Law: F = -kx

    Fibrosis lung recoil

    Ppl= -8

    Intrapleuralspace

    Ppl = -2

    Emphysema lung recoil

    Incr

    easi

    ngvo

    lum

    eD

    ecre

    asin

    gvo

    lum

    e

    Ppl = 0

    Pneumo-thorax

    NormalFRC

    Ppl = -5

    LungChest Wall

    StuckTogether

    Lung

    As we remove airfrom pleural spacethe lung expands& the chest wallgets pulled in.

    ChestWall

    RecoilForce

    Lung Wall

    RecoilForce

    NormalFRC

    Ppl = -5

    Normal

    Balance of Forces Determines FRCHookes Law: F = -kx

    Intrapleuralspace In

    crea

    sing

    volu

    me

    Dec

    reas

    ing

    volu

    me

    Ppl = 0

    Ppl = -2

    Emphysema lung recoil

    Fibrosis lung recoil

    Pneumo-thorax

    Ppl= -8

  • 4

    Sur

    face

    Are

    a (r

    elat

    ive)

    Surface Tension (dynes/cm)30 60

    WaterDetergent

    LungSurfactant Plasma

    80

    Surface Area Surface Tension

    Surfactant40% Dipalmitoyl Lecithin25% Unsaturated Lecithins

    8% Cholesterol27% Apoproteins, other

    phospholipids, glycerides,fatty acids

    Hyste

    resis

    Sur

    face

    Are

    a (r

    elat

    ive)

    Surface Tension (dynes/cm)30 60

    WaterDetergent

    LungSurfactant

    80

    Surface Area Surface Tension

    1. Reduces Work of Breathing2. Increases Alveolar Stability

    (different sizes coexist)3. Keeps Alveoli Dry

    -18-16-14-12-10-8-6-4-202

    Normal

    VTFRCN

    PIP (cm H2O)

    Lung

    Vol

    ume

    Expiration

    Inspiration

    Hysteresis Occurs During Dynamic Air FlowDue to Surfactant reorientation & Airway Resistance

    Static Lung Compliance Curve

    Static Compliance Curves

    -18-16-14-12-10-8-6-4-202

    Fibrosis(low compliance)

    Normal

    Emphysema(high compliance)

    VTFRCN VTFRCF

    VTFRCE

    Intrapleural Pressure, PIP (cm H2O)

    Lung

    Vol

    ume

    ChestWall

    RecoilForce

    Lung Wall

    RecoilForce

    NormalFRC

    PIP = -5

    Normal

    Balance of Forces Determines FRCHookes Law: F = -kx

    Intrapleuralspace In

    crea

    sing

    volu

    me

    Dec

    reas

    ing

    volu

    me

    PIP = 0

    PIP = -2

    Emphysema lung recoil

    Fibrosis lung recoil

    Pneumo-thorax

    PIP= -8

  • 5

    Lung has weight

    -8

    PIP = -2

    -5

    Apex

    Base

    Chest Wall

    Regional- Apex to Base Differences

    -14-12-10-8-6-4-202

    Apex

    Base

    Norm Lung Volume

    Alveolar VolumeAlve Ventilation

    Apex Base

    ++ ++

    Inspiration

    Inspiration

    PIP (cm H2O)

    Lung

    Vol

    ume

    Regional- Apex to Base Differences

    -14-12-10-8-6-4-202

    ApexV

    Base

    Low Lung Volume(shifts to lower V)

    Alveolar VolumeAlve Ventilation

    Apex Base++++

    PIP (cm H2O)

    Lung

    Vol

    ume

    Apex to Base Differences

    -14-12-10-8-6-4-202

    ApexV

    Base

    Low Lung V

    Normal Lung V

    PIP (cm H2O)

    Lung

    Vol

    ume

    The dashed trace is the PIPrequired to overcome recoil forces(ot PTP taken from compliance curve).More PIP (solid curve) is required toovercome airway resistance to flow.N.B. P = PA-PB ResistFlow.

    Air Flow (L/s)

    +1

    -1

    0

    +0.6

    -0.6

    0

    PA(cm H2O)

    1 2 3 4time (sec)

    -5

    -8

    cmH

    2O

    VT (L)0.4

    0

    0.2

    Respiratory Cycle

    Inspiration Expiration

    PTP

    PIP

    PTP

    PIP PB=0

    -5

    -7

    -8

    -6

    -5

    Rest FRC

    Inspiration

    End Inspiration

    +

    0

    0

    -AirFlow

    PA= 0

    PIP

    End Expi-ration-FRC

    Expiration

    time

    Respiratory CycleSingle VT Breath

    Static Compliance Curves

    -18-16-14-12-10-8-6-4-202

    Normal

    VTFRCN

    Pleural Pressure, Ppl (cm H2O)

    Lung

    Vol

    ume

    Expiration

    Inspiration

  • 6

    PA (cm H2O)+1

    -1

    0

    +0.5

    -0.5

    0

    Air Flow (L/s)

    1 2 3 4time (sec)

    -5

    -8

    Ppl (cm H2O)

    Case of ZERO Resistance

    VT (L)0.4

    0

    0.2

    Respiratory Cycle

    Inspiration Expiration

    -5

    -8

    -8

    -6

    -5

    Rest FRC

    Inspiration

    End Inspiration

    +

    0

    0

    -Air

    Flow

    PA= 0

    Ppl

    End Expi-ration-FRC

    Expiration

    time

    Respiratory CycleSingle VT Breath

    PB=0

    PA (cm H2O)+1

    -1

    0

    +0.5

    -0.5

    0

    Air Flow (L/s)

    1 2 3 4time (sec)

    -5

    -8

    Ppl (cm H2O)

    The linear Dashed trace is the Pplrequired to overcome recoil forces.More Ppl (solid curve) is required toovercome airway resistance to flow.N.B. P = PA-PB ResistFlow.

    VT (L)0.4

    0

    0.2

    Respiratory Cycle

    Inspiration Expiration

    -5

    -8

    -8

    -6

    -5

    Rest FRC

    Inspiration

    End Inspiration

    +

    0

    0

    -Air

    Flow

    PA= 0

    Ppl

    End Expi-ration-FRC

    Expiration

    time

    Respiratory CycleSingle VT Breath

    PB=0

    PA (cm H2O)+1

    -1

    0

    +0.5

    -0.5

    0

    Air Flow (L/s)

    1 2 3 4time (sec)

    -5

    -8

    Ppl (cm H2O)

    VT (L)0.4

    0

    0.2

    Respiratory Cycle

    Inspiration Expiration

    -5

    -8

    -8

    -6

    -5

    Rest FRC

    Inspiration

    End Inspiration

    +

    0

    0

    -Air

    Flow

    PA= 0

    Ppl

    End Expi-ration-FRC

    Expiration

    time

    Respiratory CycleSingle VT Breath

    PB=0

    Case of HIGH Resistance

    Airway Generation5 1 0 15

    Tota

    l Cro

    ss S

    ectio

    nal A

    rea

    ConductingZone

    RespZone

    v = Flow/A

    NR= Dv/=densityD= diameterv