introduction to pulmonary medicine dr. gerald supinski professor of medicine and physiology
TRANSCRIPT
Introduction to Introduction to Pulmonary Pulmonary MedicineMedicine
Dr. Gerald SupinskiDr. Gerald Supinski
Professor of Medicine and Professor of Medicine and PhysiologyPhysiology
Topics to CoverTopics to Cover
Classification of Classification of Pulmonary DisordersPulmonary Disorders HistoryHistory Physical ExaminationPhysical Examination PFTPFT CXRCXR ABGABG CasesCases
Classification of Pulmonary Classification of Pulmonary DisordersDisorders
History: DyspneaHistory: Dyspnea
““Shortness of breath”Shortness of breath” Most common pulmonary symptomMost common pulmonary symptom
Need further characterization as to Need further characterization as to timing, severity, relationship to timing, severity, relationship to exercise, body position, relationship exercise, body position, relationship to temperature (cold)to temperature (cold)
History: Other SymptomsHistory: Other Symptoms
CoughCough FeverFever Sputum productionSputum production Nocturnal Nocturnal
awakeningawakening Chest painChest pain WeaknessWeakness Leg swellingLeg swelling
Physical ExaminationPhysical Examination
PercussionPercussion AuscultationAuscultation
PercussionPercussion Original use for wine casks:Original use for wine casks:
Effect of Altering Media Effect of Altering Media DensityDensity
Percussion ResponsesPercussion Responses
ConditionCondition ResponseResponse
Normal LungNormal Lung Normal PercussionNormal Percussion
PneumothoraxPneumothorax
EmphysemaEmphysemaIncreased Increased PercussionPercussion
““Hyperresonance”Hyperresonance”
EffusionEffusion
Consolidated LungConsolidated LungReduced Reduced PercussionPercussion
““Hyporesonance”Hyporesonance”
AuscultationAuscultation
Breath SoundsBreath Sounds
Bronchovesicular, Bronchial, Bronchovesicular, Bronchial, Reduced SoundsReduced Sounds
Adventitial Sounds Adventitial Sounds
Rales, Wheezes, RhonchiRales, Wheezes, Rhonchi
Breath Sound Breath Sound CharacteristicsCharacteristics
Frequency of sounds (pitch)Frequency of sounds (pitch) Intensity or loudness of soundsIntensity or loudness of sounds
Breath Sound ClassesBreath Sound Classes
Bronchovesicular Bronchovesicular Sounds Sounds
NormalNormal
Bronchial Breath Bronchial Breath SoundsSounds
Consolidation around Consolidation around an open airwayan open airway
Reduced Breath Reduced Breath SoundsSounds
Emphysema,Emphysema,
AsthmaAsthma
Adventitial SoundsAdventitial Sounds
RalesRales End Inspiratory “Cellophane”End Inspiratory “Cellophane”
See in CHF, ILD, pneumoniaSee in CHF, ILD, pneumonia
WheezesWheezes Can be either inspiratory (UAO)Can be either inspiratory (UAO)
or expiratory (asthma, COPD)or expiratory (asthma, COPD)
RhonchiRhonchi Non specificNon specific
Summary of Summary of History/ExamHistory/Exam
DiseaseDisease SymptomsSymptoms BreathBreath
SoundsSoundsAdventitAdventitialial
SoundsSounds
AsthmaAsthma SOB with SOB with exercise, exercise, coldcold
ReduceReducedd
WheezeWheeze
COPDCOPD Sputum Sputum productioproductionn
ReduceReducedd
WheezeWheeze
ILDILD Severe Severe dyspneadyspnea
NormalNormal RalesRales
RM RM WeaknessWeakness
Limb Limb weaknessweakness
NormalNormal--ReduceReducedd
NoneNone
Chest Wall Chest Wall Abn.Abn.
Leg Leg edemaedema
ReduceReducedd
NoneNone
NormalNormal NoneNone NormalNormal NoneNone
PFTsPFTs
Determine if normal or Determine if normal or abnormalabnormal
Classify as restrictive or Classify as restrictive or obstructiveobstructive
Determine severityDetermine severity Correlate with history, Correlate with history,
physical, CXRphysical, CXR
PFT ClassificationPFT Classification
Standard PFTsStandard PFTs
SpirometrySpirometry Flow-Volume LoopsFlow-Volume Loops Lung VolumesLung Volumes DLCODLCO Pimax, PemaxPimax, Pemax
SpirometrySpirometry
Obstructed vs RestrictedObstructed vs Restricted
DDX of SpirometryDDX of Spirometry
NormalNormal ObstructObstructionion
RestrictiRestrictionon
FEV1FEV1 NN ↓↓↓↓↓↓ ↓↓↓↓
FVCFVC NN ↓↓ ↓↓↓↓
FEV1/FEV1/FVCFVC
NN ↓↓↓↓ NN
Reversibility Reversibility
Lung VolumesLung Volumes
Lung Volumes Lung Volumes ComponentsComponents
Lung Volume Lung Volume ComponentsComponents
DLCODLCO
Diffusion capacity for carbon dioxideDiffusion capacity for carbon dioxide A measure of gas exchangeA measure of gas exchange Patient breathes a small amount of Patient breathes a small amount of
CO and uptake determinedCO and uptake determined
Concept of DLCOConcept of DLCO
DDX of DLCODDX of DLCO
DLCODLCO ConditionCondition
NormalNormal Normals, Muscle Normals, Muscle disease, Chest wall disease, Chest wall diseasedisease
ReducedReduced COPD, ILD, Sarcoidosis,COPD, ILD, Sarcoidosis,
Pneumonia Pneumonia
IncreasedIncreased AsthmaAsthma
Pimax and PemaxPimax and Pemax
Pimax measures inspiratory Pimax measures inspiratory strengthstrength
Pemax measures expiratory Pemax measures expiratory strengthstrength
Patient inhales/exhales thru Patient inhales/exhales thru mouthpiece attached to transducermouthpiece attached to transducer
Respiratory Muscle Respiratory Muscle StrengthStrength
Summary of PFTsSummary of PFTsDiseaseDisease FEVFEV
11FEVFEV1/1/FVCFVC
TLCTLC DLCDLCOO
PimaPimaxx
AsthmaAsthma ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↑↑ NN
COPDCOPD ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↓↓↓↓ ↓↓
ILDILD ↓↓↓↓ NN ↓↓↓↓ ↓↓↓↓ NN
RM RM WeaknesWeaknesss
↓↓ NN ↓↓↓↓ NN ↓↓↓↓
Chest Chest Wall Abn.Wall Abn.
↓↓ NN ↓↓↓↓ NN NN
NormalNormal NN NN NN NN NN
CXR (Chest Radiograph)CXR (Chest Radiograph)
ObstructionObstruction
Clear lung fields, can see Clear lung fields, can see hyperinflationhyperinflation
Restricted-Interstitial PatternRestricted-Interstitial Pattern
Lines and nodulesLines and nodules Restricted-Alveolar PatternRestricted-Alveolar Pattern
See diffuse filling, air See diffuse filling, air bronchogramsbronchograms
Chest Wall/Muscle DisordersChest Wall/Muscle Disorders
Reduced lung volumeReduced lung volume
Arterial Blood GasesArterial Blood Gases
pHpH paCO2paCO2 paO2paO2 FiO2FiO2
Mechanisms of Mechanisms of HypoxemiaHypoxemia
Diffusion blockDiffusion block V/Q mismatch V/Q mismatch ShuntShunt HypoventilationHypoventilation
Determinants of PaODeterminants of PaO22
Alveolar Air Equation:Alveolar Air Equation:
PAOPAO22=FiO=FiO22(BP-VP)-PaCO(BP-VP)-PaCO22/R /R
A-a Gradient= PAOA-a Gradient= PAO22-PaO-PaO2 2
So PaOSo PaO22=FiO=FiO22(BP-VP)-PaCO(BP-VP)-PaCO22/R - A-a /R - A-a GradientGradient
Increases in Inspired Oxygen Increases in Inspired Oxygen Concentrations Concentrations
Do Not Substantially Improve paO2 Do Not Substantially Improve paO2 in in
the Presence of Substantial Shuntthe Presence of Substantial Shunt
DDX of HypoxemiaDDX of Hypoxemia
A-a GradientA-a Gradient Response to Response to 100% 100% OxygenOxygen
Diffusion Diffusion blockblock
↑↑ ↑↑↑↑
V/Q V/Q mismatchmismatch
↑↑↑↑ ↑↑↑↑
ShuntShunt ↑↑↑↑ Poor Poor responseresponse
HypoventilatHypoventilationion
NormalNormal ↑↑↑↑
Mechanisms of Mechanisms of HypercapniaHypercapnia
Increased CO2 Increased CO2 productionproduction
Reduced minute Reduced minute ventilationventilation
Increased dead spaceIncreased dead space
Dead SpaceDead Space
Mathematical Mathematical RelationshipsRelationships
The following equation determines The following equation determines paCO2: paCO2:
paCO2 = paCO2 = VCO2 (k)VCO2 (k)
VE-VDVE-VD
Causes of HypercapniaCauses of Hypercapnia
Mechanism of Mechanism of ↑CO2↑CO2
EtiologiesEtiologies
Increased CO2 Increased CO2 productionproduction
Fever, Fever, thyrotoxicosisthyrotoxicosis
Increased dead Increased dead spacespace
COPD, asthma, COPD, asthma, ILD, ARDS, ILD, ARDS, pneumoniapneumonia
Reduced Reduced ventilationventilation
Weakness, chest Weakness, chest wall disease, wall disease, fatigue, UAOfatigue, UAO
Summary of CXR/ABGSummary of CXR/ABG
DiseaseDisease CXRCXR PaOPaO22
Dead Dead
SpaceSpaceVeVe
AsthmaAsthma HyperinflatHyperinflateded
↓↓ ↑↑ VarVaryy
COPDCOPD HyperinflatHyperinflateded
↓↓↓↓ ↑↑↑↑↑↑ VarVaryy
ILDILD Lines/Lines/nodulesnodules
↓↓↓↓↓↓ ↑↑ VarVaryy
RM RM WeaknessWeakness
Clear, Clear, smallsmall
↓↓ NN ↓↓
Chest Wall Chest Wall Abn.Abn.
Clear, Clear, smallsmall
↓↓ NN ↓↓
NormalNormal NormalNormal NN NN NN
A clinic patient complains of shortness of breath A clinic patient complains of shortness of breath for the past 9 months. Spirometry and lung for the past 9 months. Spirometry and lung volume measurements are read as showing a volume measurements are read as showing a restrictive abnormality. The differential diagnosis restrictive abnormality. The differential diagnosis of this patient consists of three disorders, of this patient consists of three disorders, including:including:
A) Bronchitis, asthma, sleep apneaA) Bronchitis, asthma, sleep apneaB) Chest wall disorders, muscle weakness, B) Chest wall disorders, muscle weakness,
interstitial lung diseaseinterstitial lung diseaseC) Upper airway diseases, asthma, COPDC) Upper airway diseases, asthma, COPDD) Pulmonary embolism, cardiomegaly, liver D) Pulmonary embolism, cardiomegaly, liver
diseasediseaseE) Emphysema, muscle weakness, E) Emphysema, muscle weakness,
hepatopulmonary syndromehepatopulmonary syndrome
A clinic patient complains of shortness of breath A clinic patient complains of shortness of breath for the past 9 months. Spirometry and lung for the past 9 months. Spirometry and lung volume measurements are read as showing a volume measurements are read as showing a restrictive abnormality. The differential diagnosis restrictive abnormality. The differential diagnosis of this patient consists of three disorders, of this patient consists of three disorders, including:including:
A) Bronchitis, asthma, sleep apneaA) Bronchitis, asthma, sleep apneaB) B) Chest wall disorders, muscle weakness, Chest wall disorders, muscle weakness,
interstitial lung diseaseinterstitial lung diseaseC) Upper airway diseases, asthma, COPDC) Upper airway diseases, asthma, COPDD) Pulmonary embolism, cardiomegaly, liver D) Pulmonary embolism, cardiomegaly, liver
diseasediseaseE) Emphysema, muscle weakness, E) Emphysema, muscle weakness,
hepatopulmonary syndromehepatopulmonary syndrome
A patient has a long history of dyspnea. The A patient has a long history of dyspnea. The physical examination reveals reduced breath physical examination reveals reduced breath sound and hyperresonance. The chest sound and hyperresonance. The chest radiograph shows emphysema. Which PFT radiograph shows emphysema. Which PFT results are likely to be observed?results are likely to be observed?
A) A reduced FEV1, a reduced FVC and a normal A) A reduced FEV1, a reduced FVC and a normal FEV1/FVC ratioFEV1/FVC ratio
B) A markedly reduced FEV1, a reduced FVC, a B) A markedly reduced FEV1, a reduced FVC, a reduced FEV1/FVC ratioreduced FEV1/FVC ratio
C) A reduced FEV1, a normal FVC and a normal C) A reduced FEV1, a normal FVC and a normal FEV1/FVC ratioFEV1/FVC ratio
D) Reduced FEV1, increased FVC and an D) Reduced FEV1, increased FVC and an increased FEV1/FVC ratioincreased FEV1/FVC ratio
E) Normal FEV1, normal FVC, and a normal E) Normal FEV1, normal FVC, and a normal FEV1/FVC ratioFEV1/FVC ratio
A patient has a long history of dyspnea. The A patient has a long history of dyspnea. The physical examination reveals reduced breath physical examination reveals reduced breath sound and hyperresonance. The chest sound and hyperresonance. The chest radiograph shows emphysema. Which PFT radiograph shows emphysema. Which PFT results are likely to be observed?results are likely to be observed?
A) A reduced FEV1, a reduced FVC and a normal A) A reduced FEV1, a reduced FVC and a normal FEV1/FVC ratioFEV1/FVC ratio
B) B) A markedly reduced FEV1, a reduced FVC, a A markedly reduced FEV1, a reduced FVC, a reduced FEV1/FVC ratioreduced FEV1/FVC ratio
C) A reduced FEV1, a normal FVC and a normal C) A reduced FEV1, a normal FVC and a normal FEV1/FVC ratioFEV1/FVC ratio
D) Reduced FEV1, increased FVC and an D) Reduced FEV1, increased FVC and an increased FEV1/FVC ratioincreased FEV1/FVC ratio
E) Normal FEV1, normal FVC, and a normal E) Normal FEV1, normal FVC, and a normal FEV1/FVC ratioFEV1/FVC ratio
NormalNormal ObstructObstructionion
RestrictiRestrictionon
FEV1FEV1 NN ↓↓↓↓↓↓ ↓↓↓↓
FVCFVC NN ↓↓ ↓↓↓↓
FEV1/FEV1/FVCFVC
NN ↓↓↓↓ NN
Summary of PFTsSummary of PFTsDiseaseDisease FEVFEV
11FEVFEV1/1/FVCFVC
TLCTLC DLCDLCOO
PimaPimaxx
AsthmaAsthma ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↑↑ NN
COPDCOPD ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↓↓↓↓ ↓↓
ILDILD ↓↓↓↓ NN ↓↓↓↓ ↓↓↓↓ NN
RM RM WeaknesWeaknesss
↓↓ NN ↓↓↓↓ NN ↓↓↓↓
Chest Chest Wall Abn.Wall Abn.
↓↓ NN ↓↓↓↓ NN NN
NormalNormal NN NN NN NN NN
A patient has expiratory wheezing, A patient has expiratory wheezing, shortness of breath and cough. PFTs shortness of breath and cough. PFTs show a reduced FEV1, a mildly reduced show a reduced FEV1, a mildly reduced FVC, a reduced FEV1/FVC ratio, a FVC, a reduced FEV1/FVC ratio, a reduced DLCO. The chest Xray is clear. reduced DLCO. The chest Xray is clear. Which is the most likely diagnosis:Which is the most likely diagnosis:
A) COPDA) COPDB) BronchiectesisB) BronchiectesisC) SarcoidosisC) SarcoidosisD) AsthmaD) AsthmaE) Upper airway obstructionE) Upper airway obstruction
A patient has expiratory wheezing, A patient has expiratory wheezing, shortness of breath and cough. PFTs shortness of breath and cough. PFTs show a reduced FEV1, a mildly reduced show a reduced FEV1, a mildly reduced FVC, a reduced FEV1/FVC ratio, a FVC, a reduced FEV1/FVC ratio, a reduced DLCO. The chest Xray is clear. reduced DLCO. The chest Xray is clear. Which is the most likely diagnosis:Which is the most likely diagnosis:
A) A) COPDCOPDB) BronchiectesisB) BronchiectesisC) SarcoidosisC) SarcoidosisD) AsthmaD) AsthmaE) Upper airway obstructionE) Upper airway obstruction
Summary of PFTsSummary of PFTsDiseaseDisease FEVFEV
11FEVFEV1/1/FVCFVC
TLCTLC DLCDLCOO
PimaPimaxx
AsthmaAsthma ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↑↑ NN
COPDCOPD ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↓↓↓↓ ↓↓
ILDILD ↓↓↓↓ NN ↓↓↓↓ ↓↓↓↓ NN
RM RM WeaknesWeaknesss
↓↓ NN ↓↓↓↓ NN ↓↓↓↓
Chest Chest Wall Abn.Wall Abn.
↓↓ NN ↓↓↓↓ NN NN
NormalNormal NN NN NN NN NN
A clinic patient complains of dyspnea, has A clinic patient complains of dyspnea, has rales on physical examination, the FEV1 is rales on physical examination, the FEV1 is reduced, the FEV1/FVC ratio is normal, DLCO reduced, the FEV1/FVC ratio is normal, DLCO is reduced and the CXR shows a is reduced and the CXR shows a reticulonodular infiltrate. What is the most reticulonodular infiltrate. What is the most consistent diagnosis:consistent diagnosis:
A) AsthmaA) Asthma
B) EmphysemaB) Emphysema
C) Interstitial Lung DiseaseC) Interstitial Lung Disease
D) Upper Airway ObstructionD) Upper Airway Obstruction
E) Chest wall diseaseE) Chest wall disease
A clinic patient complains of dyspnea, has A clinic patient complains of dyspnea, has rales on physical examination, the FEV1 is rales on physical examination, the FEV1 is reduced, the FEV1/FVC ratio is normal, DLCO reduced, the FEV1/FVC ratio is normal, DLCO is reduced and the CXR shows a is reduced and the CXR shows a reticulonodular infiltrate. What is the most reticulonodular infiltrate. What is the most consistent diagnosis:consistent diagnosis:
A) AsthmaA) Asthma
B) EmphysemaB) Emphysema
C) C) Interstitial Lung DiseaseInterstitial Lung Disease
D) Upper Airway ObstructionD) Upper Airway Obstruction
E) Chest wall diseaseE) Chest wall disease
Summary of Summary of History/ExamHistory/Exam
DiseaseDisease SymptomsSymptoms BreathBreath
SoundsSoundsAdventitAdventitialial
SoundsSounds
AsthmaAsthma SOB with SOB with exercise, exercise, coldcold
ReduceReducedd
WheezeWheeze
COPDCOPD Sputum Sputum productioproductionn
ReduceReducedd
WheezeWheeze
ILDILD Severe Severe dyspneadyspnea
NormalNormal RalesRales
RM RM WeaknessWeakness
Limb Limb weaknessweakness
NormalNormal--ReduceReducedd
NoneNone
Chest Wall Chest Wall Abn.Abn.
Leg Leg edemaedema
ReduceReducedd
NoneNone
NormalNormal NoneNone NormalNormal NoneNone
Summary of PFTsSummary of PFTsDiseaseDisease FEVFEV
11FEVFEV1/1/FVCFVC
TLCTLC DLCDLCOO
PimaPimaxx
AsthmaAsthma ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↑↑ NN
COPDCOPD ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↓↓↓↓ ↓↓
ILDILD ↓↓↓↓ NN ↓↓↓↓ ↓↓↓↓ NN
RM RM WeaknesWeaknesss
↓↓ NN ↓↓↓↓ NN ↓↓↓↓
Chest Chest Wall Abn.Wall Abn.
↓↓ NN ↓↓↓↓ NN NN
NormalNormal NN NN NN NN NN
Summary of CXR/ABGSummary of CXR/ABG
DiseaseDisease CXRCXR PaOPaO22
Dead Dead
SpaceSpaceVeVe
AsthmaAsthma HyperinflatHyperinflateded
↓↓ ↑↑↑↑ VarVaryy
COPDCOPD HyperinflatHyperinflateded
↓↓↓↓ ↑↑↑↑↑↑ VarVaryy
ILDILD Lines/Lines/nodulesnodules
↓↓↓↓↓↓ ↑↑ VarVaryy
RM RM WeaknessWeakness
Clear, Clear, smallsmall
↓↓ NN ↓↓
Chest Wall Chest Wall Abn.Abn.
Clear, Clear, smallsmall
↓↓ NN ↓↓
NormalNormal NormalNormal NN NN NN
You see a patient on the medical ward You see a patient on the medical ward who complains of dyspnea and difficulty who complains of dyspnea and difficulty standing. The FEV1 is reduced, the standing. The FEV1 is reduced, the FEV1/FVC is normal, the TLC is reduced, FEV1/FVC is normal, the TLC is reduced, the DLCO is normal, the CXR is clear. A the DLCO is normal, the CXR is clear. A possible diagnosis is:possible diagnosis is:
A) Interstitial lung diseaseA) Interstitial lung diseaseB) AsthmaB) AsthmaC) Respiratory muscle weaknessC) Respiratory muscle weaknessD) BronchiectesisD) BronchiectesisE) AsbestosisE) Asbestosis
You see a patient on the medical ward You see a patient on the medical ward who complains of dyspnea and difficulty who complains of dyspnea and difficulty standing. The FEV1 is reduced, the standing. The FEV1 is reduced, the FEV1/FVC is normal, the TLC is reduced, FEV1/FVC is normal, the TLC is reduced, the DLCO is normal, the CXR is clear. A the DLCO is normal, the CXR is clear. A possible diagnosis is:possible diagnosis is:
A) Interstitial lung diseaseA) Interstitial lung diseaseB) AsthmaB) AsthmaC) C) Respiratory muscle weaknessRespiratory muscle weaknessD) BronchiectesisD) BronchiectesisE) AsbestosisE) Asbestosis
Summary of PFTsSummary of PFTsDiseaseDisease FEVFEV
11FEVFEV1/1/FVCFVC
TLCTLC DLCDLCOO
PimaPimaxx
AsthmaAsthma ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↑↑ NN
COPDCOPD ↓↓↓↓↓↓
↓↓↓↓ ↑↑ ↓↓↓↓ ↓↓
ILDILD ↓↓↓↓ NN ↓↓↓↓ ↓↓↓↓ NN
RM RM WeaknesWeaknesss
↓↓ NN ↓↓↓↓ NN ↓↓↓↓
Chest Chest Wall Abn.Wall Abn.
↓↓ NN ↓↓↓↓ NN NN
NormalNormal NN NN NN NN NN
A patient has been diagnosed with A patient has been diagnosed with hypersensitivity pneumonitis, a form of hypersensitivity pneumonitis, a form of interstitial lung disease. What lung volume interstitial lung disease. What lung volume measurements are likely to be present:measurements are likely to be present:
A) Reduced TLC, increased FRCA) Reduced TLC, increased FRC
B) Increased TLC, normal FRCB) Increased TLC, normal FRC
C) Reduced TLC, normal FRCC) Reduced TLC, normal FRC
D) Reduced TLC, reduced FRCD) Reduced TLC, reduced FRC
E) Increased TLC, normal FRCE) Increased TLC, normal FRC
A patient has been diagnosed with A patient has been diagnosed with hypersensitvity pneumonitis, a form of hypersensitvity pneumonitis, a form of interstitial lung disease. What lung volume interstitial lung disease. What lung volume measurements are likely to be present:measurements are likely to be present:
A) Reduced TLC, increased FRCA) Reduced TLC, increased FRC
B) Increased TLC, normal FRCB) Increased TLC, normal FRC
C) Reduced TLC, normal FRCC) Reduced TLC, normal FRC
D) D) Reduced TLC, reduced FRCReduced TLC, reduced FRC
E) Increased TLC, normal FRCE) Increased TLC, normal FRC
A patient is breathing 50% oxygen, the A patient is breathing 50% oxygen, the barometric pressure is 747, the vapor barometric pressure is 747, the vapor pressure of water is 47, the carbon dioxide pressure of water is 47, the carbon dioxide level is 40, the respiratory quotient is 0.8. level is 40, the respiratory quotient is 0.8. What is the alveolar oxygen level (PA02)?What is the alveolar oxygen level (PA02)?
A) 33A) 33B) 500B) 500C) 300C) 300D) 200D) 200E) 97E) 97
A patient is breathing 50% oxygen, the A patient is breathing 50% oxygen, the barometric pressure is 747, the vapor barometric pressure is 747, the vapor pressure of water is 47, the carbon dioxide pressure of water is 47, the carbon dioxide level is 40, the respiratory quotient is 0.8. level is 40, the respiratory quotient is 0.8. What is the alveolar oxygen level (PA02)?What is the alveolar oxygen level (PA02)?
A) 33A) 33B) 500B) 500C) C) 300300D) 200D) 200E) 97E) 97
PAOPAO22=FiO=FiO22(BP-VP)-PaCO(BP-VP)-PaCO22/R/R
PAOPAO22=.50(747-47)-40/0.8=.50(747-47)-40/0.8
PAOPAO22=.50(700)-50 = 350-50= =.50(700)-50 = 350-50= 300300
A patient presents with increased arterial carbon A patient presents with increased arterial carbon dioxide level, a history of muscle weakness, and dioxide level, a history of muscle weakness, and prior thyrotoxicosis. Which of the following tests prior thyrotoxicosis. Which of the following tests will help determine whether the current will help determine whether the current increased carbon dioxide is from muscle increased carbon dioxide is from muscle weakness or thyroid disease?weakness or thyroid disease?
A) Measurement of dead spaceA) Measurement of dead space
B) Measurement of the level of carbon dioxide B) Measurement of the level of carbon dioxide productionproduction
C) Measurement of nitrogen balanceC) Measurement of nitrogen balance
D) Measurement of alveolar-arterial gradientD) Measurement of alveolar-arterial gradient
E) A chest radiographE) A chest radiograph
A patient presents with increased arterial carbon A patient presents with increased arterial carbon dioxide level, a history of muscle weakness, and dioxide level, a history of muscle weakness, and prior thyrotoxicosis. Which of the following tests prior thyrotoxicosis. Which of the following tests will help determine whether the current will help determine whether the current increased carbon dioxide is from muscle increased carbon dioxide is from muscle weakness or thyroid disease?weakness or thyroid disease?
A) Measurement of dead spaceA) Measurement of dead space
B) B) Measurement of the level of carbon dioxide Measurement of the level of carbon dioxide productionproduction
C) Measurement of nitrogen balanceC) Measurement of nitrogen balance
D) Measurement of alveolar-arterial gradientD) Measurement of alveolar-arterial gradient
E) A chest radiographE) A chest radiograph
Causes of HypercapniaCauses of Hypercapnia
Mechanism of Mechanism of ↑CO2↑CO2
EtiologiesEtiologies
Increased CO2 Increased CO2 productionproduction
Fever, Fever, thyrotoxicosisthyrotoxicosis
Increased dead Increased dead spacespace
COPD, asthma, COPD, asthma, ILD, ARDS, ILD, ARDS, pneumoniapneumonia
Reduced Reduced ventilationventilation
Weakness, chest Weakness, chest wall disease, wall disease, fatigue, UAOfatigue, UAO
A patient presents with blue lips. An arterial A patient presents with blue lips. An arterial blood gas shows a paO2 that is 40 mm Hg. The blood gas shows a paO2 that is 40 mm Hg. The patient is placed on 100% oxygen and the patient is placed on 100% oxygen and the arterial blood gas improves to 650 mm Hg. The arterial blood gas improves to 650 mm Hg. The A-a gradient is normal. What is the likely cause A-a gradient is normal. What is the likely cause of hypoxemia in this patient?of hypoxemia in this patient?
A) Diffusion blockA) Diffusion blockB) Ventilaton-perfusion mismatchB) Ventilaton-perfusion mismatchC) ShuntC) ShuntD) HypoventilationD) HypoventilationE) Elevated dead space E) Elevated dead space
A patient presents with blue lips. An arterial A patient presents with blue lips. An arterial blood gas shows a paO2 that is 40 mm Hg. The blood gas shows a paO2 that is 40 mm Hg. The patient is placed on 100% oxygen and the patient is placed on 100% oxygen and the arterial blood gas improves to 650 mm Hg. The arterial blood gas improves to 650 mm Hg. The A-a gradient is normal. What is the likely cause A-a gradient is normal. What is the likely cause of hypoxemia in this patient?of hypoxemia in this patient?
A) Diffusion blockA) Diffusion blockB) Ventilaton-perfusion mismatchB) Ventilaton-perfusion mismatchC) ShuntC) ShuntD) HypoventilationD) HypoventilationE) Elevated dead space E) Elevated dead space
DDX of HypoxemiaDDX of Hypoxemia
A-a GradientA-a Gradient Response to Response to 100% 100% OxygenOxygen
Diffusion Diffusion blockblock
↑↑ ↑↑↑↑
V/Q V/Q mismatchmismatch
↑↑↑↑ ↑↑↑↑
ShuntShunt ↑↑↑↑ Poor Poor responseresponse
HypoventilatHypoventilationion
NormalNormal ↑↑↑↑