Transcript CHRONIC OBSTRUCTIVE PULMONARY DISEASE CLINICAL PRACTICE

CHRONIC OBSTRUCTIVE
PULMONARY DISEASE
CLINICAL PRACTICE GUIDELINES REVIEW
WEEK 1: DIAGNOSIS
AMBULATORY INTERNAL MEDICINE
GROUP PRACTICE
UNIVERSITY HEALTH NETWORK / MSH
SEPTEMBER 2007
Prepared by: Dr. D. Panisko
COPD: Guidelines for this Seminar
 Standards for the diagnosis and treatment of patients with
COPD: a summary of the ATS/ERS position paper. Celli BR et
al. Eur Respir J 2004; 23: 932-46. Full document, with updates,
available at: www.thoracic.org, accessed Sept 2007
 Canadian Thoracic Society recommendations for the
management of chronic obstructive pulmonary disease 2003. O’Donnell DE et al. Can Respir J 2003; 10(SupplA): 11A33A
 Global Initiative for Chronic Obstructive Lung Disease.
(GOLD). A collaborative of the NIH and WHO. Updated Nov 2006,
accessed Sept 2007. Available at www.goldcopd.com
COPD Diagnosis: Objectives
 After this seminar you should:
 be aware of diagnostic clinical practice
guidelines for stable chronic COPD
 be able to define COPD and asthma and
outline a differential diagnosis
 be able list important historical and
laboratory diagnostic features of COPD
 be able to describe the evidence-based
physical examination for COPD and
airflow limitation
COPD I:
DIAGNOSIS
CASE:
A 61 year old man comes to your clinic as a new
patient. He had just been admitted to hospital for
his first exacerbation of COPD. He has completed
a 10 day antibiotic course and 10 days of oral
Prednisone. He is now only on an ipratropium
puffer, 2 puffs qid.
 How is COPD defined ? What is emphysema ?
What is asthma ?
 Why is it important to make a diagnosis of
COPD (as opposed to asthma) in this patient ?
COPD I:
DIAGNOSIS
 COPD Definition:
 A preventable and treatable disease state
characterized by airflow limitation that is not fully
reversible.
 The airflow limitation is usually progressive and
associated with an abnormal inflammatory response
of the lungs to noxious particles or gases, primarily
caused by cigarette smoking.
 Although COPD affects the lungs, it also produces
significant systemic consequences.
 Implies post bronchodilator FEV1/FVC<0.7
ATS/ERS position paper
COPD I:
DIAGNOSIS
 COPD: traditionally understood as a spectrum components of chronic bronchitis or emphysema.
The latter may take on revitalized significance
because of a new approach that considers the
importance of different phenotypes of COPD.
 EMPHYSEMA: Abnormal permanent enlargement
of the airspaces distal to the terminal bronchioles,
accompanied by destruction (lack of uniformity in
the pattern of airspace enlargement; the orderly
appearance of the acinus and its components is
disturbed and may be lost) of their walls and
without obvious fibrosis.
Emphysema = Pink Puffer !
Gross Pathological Changes of Emphysema
Microscopic Changes of Emphysema
COPD I:
DIAGNOSIS
 ASTHMA: A chronic inflammatory disorder of the
tracheobronchial tree, many cells and cellular
elements play a role, leading to airway
hyperreactivity and reversible airflow limitation.
IMPLICATION: airway can return to normal
between attacks or with treatment BUT in chronic
asthma a condition similar to COPD can develop
with irreversibility and progression of the airflow
limitation.
 It is also important to make a diagnosis of
asthma as there are differences in therapy for
asthma and COPD.
COPD I:
DIAGNOSIS
CASE (cont.):
 Can the severity of COPD be staged ?
 What is the relevance and importance of staging
a patient with COPD ?
GOLD: Classification of COPD
Severity by Spirometry
Stage I: Mild
FEV1/FVC < 0.70
FEV1 > 80% predicted
Stage II: Moderate
FEV1/FVC < 0.70
50% < FEV1 < 80% predicted
Stage III: Severe
FEV1/FVC < 0.70
30% < FEV1 < 50% predicted
Stage IV: Very Severe
FEV1/FVC < 0.70
FEV1 < 30% predicted or
FEV1 < 50% predicted plus
chronic respiratory failure
COPD I:
DIAGNOSIS
 What is the relevance and importance of
staging a patient with COPD ?
 Stages (GOLD) are currently mainly for
educational and research purposes
 Not extensively validated by trials
 Represent expert consensus opinion
 Some treatment recommendations exist based
on patient stage… presumably will be further
validated by clinical trials
 Canadian guidelines list another severity scale
but do not recommend treatment on that basis
COPD I:
DIAGNOSIS
CASE (cont.):
 What historical features contribute to the
diagnosis of COPD ?
 What are other important features of the hx ?
COPD I:
DIAGNOSIS
 Important historical information:
 age of onset of symptoms
 quantify exposure to risk factors i.e.:
 tobacco smoke
 occupational exposures
 exposure to outdoor and indoor air pollution
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presence of liver disease
family history
childhood respiratory illnesses
information that allows a diagnosis of chronic
bronchitis
COPD I:
DIAGNOSIS
 Perform respiratory functional inquiry to
determine current symptom status and to classify
COPD:
 asymptomatic
 intermittent symptoms (on exertion,
nocturnal/sleep)
 regularly symptomatic
 severely symptomatic
 frequency and course of exacerbations
COPD I:
DIAGNOSIS
CASE (cont.):
 What is the differential diagnosis of COPD ?
COPD I:
DIAGNOSIS
Differential Diagnosis of COPD:
Cystic fibrosis, asthma, bronchiectasis, and
bronchiolitis obliterans (all specific causes of
airflow limitation) have been conventionally
excluded from the diagnosis definition of COPD and
therefore are part of the dx dx.
 Interstitial lung disease (fibrosis, TB,
hypersensitivity pneumonitis, sarcoidosis,
pneumoconioses, etc.) may also present in a
patient with recurrent shortness of breath,
exacerbations, and cough.
 Consider a variety of non-pulmonary causes of
breathlessness (i.e. CHF)
COPD I:
DIAGNOSIS
CASE (cont.):
This patient indicates a three year history of
productive cough, at least on 50% of days, and an
audible wheeze with SOBOE. His symptoms have
been progressing over the entire year and he now
gets SOB with 1 flight of stairs or 3 level blocks. He
has a 45 pack year smoking history, has worked in
an office all of his life, and has no relevant past
medical, childhood, or family history.
 What are indications for screening for alpha-1
antitrypsin deficiency ?
 Should this patient be screened?
 How can screening be performed ?
COPD I:
DIAGNOSIS
 Screen for alpha-1 antitrypsin deficiency if patient
 is under the age of 45,
 has a predominance of basilar emphysema,
 has a minimal smoking history,
 has a family history of early onset COPD,
 has a known family history of alpha-1 antitrypsin
deficiency, or associated liver disease.
 Screening therefore not indicated in the case.
 Screening: serum assay for alpha-1 antitrypsin level – 10cc
of clotted blood in red top tube (on a misc. req. at UHN). For
update on genetics of COPD see Rabe et al. 2007
COPD I:
DIAGNOSIS
CASE:
 What physical exam maneuvers are
helpful to diagnose airflow limitation ?
Not this
one !!!
COPD I:
DIAGNOSIS
Evidence Based Physical Exam:
[See: 1) Holleman, Rational Clinical Examination
Series. Does the clinical examination predict
airflow limitation ? JAMA 1995; 273: 313-9
2) Straus SE. McAlister FA. Sackett DL. Deeks JJ.
The accuracy of patient history, wheezing, &
laryngeal measurements in diagnosing obstructive
airway disease. CARE-COAD1 Group. JAMA 2000
283:1853-7
3)Straus SE. McAlister FA. Sackett DL. Deeks JJ.
Accuracy of history, wheezing, and forced
expiratory time in the diagnosis of chronic
obstructive pulmonary disease. CARE-COAD2 Group.
J Gen Intern Med 2002; 17: 684-8]
COPD I:
DIAGNOSIS
Wheezing: Grade: A Positive likelihood ratio: 36
Barrel Chest: B, 10
Decreased Cardiac Dullness: B, 10
Match Test: B, 7.1
Hyperresonance: B, 4.8
Forced Expiratory Time >9 seconds: A, 4.8
Subxiphoid Apical Impulse: B, 4.6
Pulsus Paradoxus > 15mmHg: C, 3.7
Decreased Breath Sounds: B, 3.7
Forced Expiratory Time 6 - 9 seconds: A, 2.7
* Many other signs not systematically evaluated
(diaphragmatic levels, pursed lip breathing, use of
accessory muscles, indrawing)
COPD I:
DIAGNOSIS
 Straus et al’s important contributions to the
literature have shown that a single physical sign is
not as useful as a combination of historical and
physical findings to make a diagnosis of COPD
 They have published
two models
What maneuvre is
being performed ?
COPD I:
DIAGNOSIS
Combined history/physical exam Model I:
Smoking > 40 P.Y. (LR 8.3)
Self reported history of COPD (LR 7.3)
Maximum laryngeal height (LR 2.8)
Age > 45 years (LR 1.3)
Combined all 4: +LR 220
Combined patients with none: -LR 0.13
COPD I:
DIAGNOSIS
Combined history/physical exam Model II:
*Forced Exp Time > 9 sec (LR 6.7) Multivariate: (LR 4.6)
*Self reported history of COPD (LR 5.6)
(LR 4.4)
*Wheezing (LR 4.0)
(LR 2.9)
Smoked longer than 40 pack years (LR 3.3)
Male gender (LR 1.6)
Age over 65 years (LR 1.6)
*Combined all 3: +LR 59.0
*Combined patients with none: -LR 0.3
COPD I:
DIAGNOSIS
CASE (cont.):
 Physical examination of our patient was only
relevant for a barrel chest, diffuse occasional
audible wheezes, and a forced expiratory time of 7
seconds. Laryngeal height was 5 cm.
 There were no signs of cor pulmonale.
 Otherwise, the exam was unremarkable.
COPD I:
DIAGNOSIS
CASE (cont.):
 Which of the following investigations are
currently indicated ?
 How will they help in the care of this patient ? …
in the care of other patients with stable COPD ?
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Spirometry
Full Pulmonary Function Tests
CXR
Helical CT of chest
Allergy testing
O2 saturation (rest, exercise, sleep)
ABG
COPD I:
DIAGNOSIS
 Spirometry: Performed for diagnosis, prognosis,
monitoring of therapy. FEV1, FVC, and ratio most
important; peak flows not recommended.
 Pulmonary Function Tests: Full PFT’s not
necessary for routine dx, usually performed at the
time of initial dx to establish baseline, may be
useful for dxdx - i.e to obtain bronchodilator
reversibility testing to asses for asthma.
 CXR: Useful in exacerbations and for its r/o value
for other dxdx. Has low sens. and spec. for the dx
of emphysema, thus not recommended by
guidelines.
COPD I:
DIAGNOSIS
 Helical CT of Chest: Not necessary for routine
diagnosis, may be useful for dxdx or for lung volume
reduction OR.
 Allergy Testing: May have use in asthma, not COPD.
 O2 Sat: In severe COPD (stage 2b or 3) useful to
guide O2 therapy. Nocturnal desaturations are
probably under diagnosed.
 ABG: Needed to guide long term oxygen therapy and
to obtain government funding for same. (See
guidelines for actual criteria for initiation of
treatment… will be discussed next week).
COPD I:
DIAGNOSIS
CASE (cont.):
 The current Canadian guidelines:
 do not emphasize evidence based diagnosis for
patients with COPD
 put more emphasis on evaluation of
impairment, disability with exercise testing,
dyspnea assessment scales, and quality of life
assessment scales
 do not give specific recommendations on how
or at what point in the patient’s course these
evaluations should be used
COPD: other useful references:
 2 recent review series on COPD:
 5 article series on exacerbations:
Thorax Feb – June, 2006
 12 article series:
BMJ May 13th to July 22nd, 2006
 Excellent recent update:
 Update in Chronic Obstructive Pulmonary
Disease 2006: Rabe KF, et al. Am J Resp Crit
Care 2007; 175: 1222-1232
COPD I:
DIAGNOSIS
 Next week:
COPD II - Therapy