Transcript Approach to Dyspnoea

Approach to Dyspnoea
Prof R Morar
Introduction
• Dyspnoea, breathlessness or inadequate breathing is accompanied
by the sensations of running out of air and not being able to breathe
fast or deeply enough
• The sensations are similar to that of thirst or hunger (an unignorable
feeling of needing something)
Introduction
• Various disease states can produce dyspnoea in different ways
• Perception of dyspnoea can vary greatly among individuals
• Assessment of dyspnoea must balance the concepts of physiologic
work and ventilatory demand with the individual’s perception of
breathlessness
Descriptions for Dyspnoea in Different Conditions
Rapid breathing
Chronic heart failure
Incomplete exhalation
Asthma
Shallow breathing
Restrictive lung diseases
Increased work/effort
COPD, interstitial lung disease, neuromuscular
disease, chest wall diseases
Suffocation
Chronic heart failure
Air hunger
COPD, chronic heart failure, sighing dyspnoea
Tight chest
Asthma
Heavy Breathing
Asthma
Outline
• Overview basic mechanisms of dyspnoea
• Disease states
• Clinical evaluation
• Diagnostic work-up
• Treatment
Basic Mechanisms
• The physiologic system that regulates ventilation is extraordinarily
complex
• Receptors in the airways, lung parenchyma, respiratory muscles and
chemoreceptors provide sensory feedback via vagal, phrenic and
intercostal nerves to the spinal cord, medulla and higher centres
Basic Mechanisms
Mechanoreceptors
respiratory muscles
Hypoxia
carotid and aortic bodies
Airflow
airway and parenchymal receptors
Changes in pCO2/pH
medullary center
Irritants
airway and parenchymal receptors
Medullary centre
afferent input and efferent output
Cortical function
sense of effort
Disease States
• Abnormalities of cardiopulmonary function are most
commonly associated with dyspnoea
• Other organ systems dysfunction can also manifest
dyspnoea
Disease States
• Pulmonary
• Endocrine
• Cardiovascular
• Psychogenic
• Upper Airway
• Miscellaneous
• CNS/peripheral
• Renal
• Hepatic
• Anaemia
• Sepsis
• Obesity
• Paediatric
Disease States
Pulmonary
• Parenchymal lung disease - pneumonia, restrictive lung disease,
metastatic
• Airways disease - COPD, asthma
• Pulmonary vascular disease - pulmonary embolic disease
• Pleural - pneumothorax, pleural effusion
• Pulmonary oedema
• Gastroesophageal reflux disease with aspiration
Disease States
Cardiovascular
• Congestive heart failure and pulmonary edema (anemia or
pulmonary embolism)
• Coronary artery disease - acute myocardial infarction
• Arrhythmia
• Pericarditis and pericardial effusion
• Valvular disease - mitral stenosis or atrial septal defect
Disease States
Upper airway obstruction
• Epiglottitis
• Foreign body
• Croup
• Epstein-Barr virus
Disease States
Neuromuscular
•
Neuromuscular disease is a well known cause of dyspnoea
•
Amyotrophic lateral sclerosis
•
Disease of the peripheral nerves - Guillain-Barré
•
Neuromuscular junction - myasthenia gravis
•
Muscle disease - muscular dystrophies, polymyositis
•
Severe weight loss from malnutrition, malignancy or chronic disease (weak muscles)
•
Pain
•
Aspirin overdose or paracetamol overdose
Disease States
Renal
• Renal disease leads to dyspnoea from acidosis, anemia and
fluid/volume overload
Disease States
Hepatic
• Chronic liver disease patients often complain of dyspnoea
• Mechanism of dyspnoea obscure
• One particular cause can be small arteriovenous shunts at the lung
bases
• This condition is classically associated with breathlessness and
oxyhaemoglobin desaturation on assuming the upright position as
when arising from bed in the morning (platypnoea)
Disease States
Endocrine
• Hyperthyroidism, can be associated with dyspnoea
– In this setting the sensation is probably related to the
hypermetabolic state associated with thyroid over-activity
– In the late stage dyspnoea can be associated with high-output
cardiac failure
• Metabolic acidosis e.g. diabetic ketoacidosis
Disease States
Miscellaneous
• Anaemia
• Sepsis
• Obesity
Disease States
Miscellaneous
Anaemia
• Prominent cause of dyspnoea
• Lower the haemoglobin more pronounced the dyspnoea
• Especially in acute anaemia
• Dyspnoea blunted in chronic anaemia
Disease States
Miscellaneous
Sepsis
• Early sepsis / bacteraemia associated with hyperventilation
• Hyperventilation and dyspnoea may be presenting feature
• Cause may be multifactorial (acidosis, tissue ischemia and lactic
acidosis, direct effect on the brainstem respiratory centre and
carotid bodies by various mediators)
Disease States
Miscellaneous
Obesity
• Unfit and increased effort
• Coronary artery disease
• Hypertension and left ventricular dysfunction
• Restrictive lungs
Disease States
Paediatric
• Bronchiolitis
• Croup
• Epiglottitis
• Foreign body aspiration
• Myocarditis
• DKA
Disease States
Psychogenic
• Panic attacks
• Hyperventilation
– Patients exhibit extreme anxiety with concurrent symptoms of
hyperventilation including visual complaints, dizziness, near-syncope
and perioral and finger tingling and numbness
• Sighing dyspnoea
– inability to take a deep satisfying breath at rest
• Pain
• Anxiety
History
• Determine onset, duration, and occurrence at rest or
exertion
• Activities and body positions that provoke dyspnoea
• Occupational
History
Cardiorespiratory Symptoms
• Chest pain - pleural or coronary disease), AMI
• Pleuritic chest pain - pericarditis, pneumonia, pulmonary embolism,
pneumothorax (pneumothorax - traumatic, decompression,
spontaneous, catamenial), pleuritis and pleural effusion
• Sudden shortness of breath at rest is suggestive of pulmonary
embolism or pneumothorax
• Cough - asthma, COPD, pneumonia, parenchymal lung disease
• Change in the character of sputum – infection
• Sore throat - epiglottitis
History
• Cardiac failure symptoms
– Orthopnoea, PND, pedal oedema
– Angina and IHD and LV dysfunction
• Drugs - -blockers, eye drops or poisoning
• Psychogenic - hyperventilation syndrome, anxiety
• Smoking
Severity Scale of Dyspnoea - ATS
Grade
Degree
Characteristics
0
None
Only with strenuous activity
1
Slight
When hurrying on level ground or climbing
a slight incline
2
Moderate
Needs to walk more slowly than others of
the same age or has to stop for breath
when walking at own pace on level ground
3
Severe
Stops for breath after 100 metres or after
a few minutes
4
Very severe
Housebound or dyspnoea when dressing
or undressing
Questions in Evaluation of Dyspnoea
Question
Probable Pathophysiology
Associated only with exertion?
Heart failure, restrictive or obstructive
lung disease
Associated with exertion and occurs at night?
Cough and wheeze?
Asthma or heart failure
Associated with exertion, chest, arm or neck
discomfort and concurrent nausea or sweating?
Angina pectoris
Worse when assuming upright position?
Liver disease with arteriovenous
shunts at the lung bases (platypnoea)
Present in the lateral decubitus position?
Unilateral lung or pleural disease
(trepopnoea)
Fast onset when supine, relieved by lateral or
upright positioning?
Bilateral phrenic nerve dysfunction
Occurring within minutes or hours of becoming
recumbent?
Heart failure (orthopnoea)
Clues to the Diagnosis of Dyspnoea
Symptoms in the history
Possible diagnosis
Cough
Asthma, COPD, pneumonia
Severe sore throat
Epiglottitis
Pleuritic chest pain
Pericarditis, pulmonary embolism,
pneumothorax, pneumonia, pleural effusion
Orthopnoea, nocturnal paroxysmal
dyspnoea, oedema
Congestive heart failure
Tobacco use
COPD, congestive heart failure, pulmonary
embolism
Indigestion
Gastroesophageal reflux disease, aspiration
Barking cough
Croup
Clinical Evaluation
Examination
• Organ systems mentioned, with meticulous attention to
the respiratory and cardiovascular systems
Disease States
•
Pulmonary
• Endocrine
•
Cardiovascular
• Psychogenic
•
Upper Airway
• Miscellaneous
•
Nervous system
•
Renal
•
Hepatic
• Anaemia
• Sepsis
• Obesity
• Paediatric
Examination
General Appearance and Vital Signs
• To determine the severity of dyspnoea, carefully observe respiratory
effort and rate, use of accessory muscles, mental status, and ability
to speak in full sentences
• Pulsus paradoxus
• Stridor
• Temperature
• Pulse rate, rhythm and character
• BP
Examination
General Appearance and Vital Signs
• Pallor
• Clubbing
• Cyanosis
• Oedema
• Mental status
Examination
Respiratory
•
Inspection
•
Palpate the chest for subcutaneous emphysema and crepitus
•
Hyperresonance and tracheal deviation
•
Stony dullness
•
Absent breath sounds
•
Bronchial breathing / amphoric breathing
•
Wheezes
•
Crackles
Examination
Cardiovascular
•
Displaced apex beat and character
•
Parasternal heave
•
An S3 gallop suggests a left ventricular systolic dysfunction in congestive heart failure
•
An S4 gallop suggests left ventricular dysfunction or ischemia
•
Loud P2 - pulmonary hypertension or cor pulmonale
•
Murmurs can be an indirect sign of congestive heart failure
•
Distant heart sounds can point to pericardial effusion and cardiac tamponade
•
Pericardial friction rub
Examination
Neck
• Raised JVP - congestive heart failure, cardiac tamponade, cor
pulmonale
• Thyroid - congestive heart failure may result from hyperthyroidism or
hypothyroidism
• Auscultate for stridor
Examination
Abdominal Examination
• Tender hepatomegaly and ascites
• Hepatojugular reflux
• Liver disease - cirrhosis
• Renal disease - enlarged kidneys, uraemic frost, pallor and HT
Examination
Extremities
• Deep venous thrombosis
Neurological examination
•
•
•
•
•
Higher functions
Motor - proximal weakness
Neuromuscular disorders
Muscle diseases
Fasciculations
Endocrine
• Thyrotoxicosis or myxoedema
Physical Examination Findings
Findings
Possible diagnosis
Wheezing, pulsus paradoxus, accessory
muscle use
Acute asthma, COPD exacerbation
Wheezing, barrel chest, decreased breath
sounds
COPD exacerbation
Fever, crackles, increased fremitus
Pneumonia
Oedema, neck vein distension, S3 or S4
hepatojugular reflux, murmurs, crackles,
hypertension, wheezing
Congestive heart failure, pulmonary
oedema
Wheezing, friction rub, lower extremity
swelling
Pulmonary embolism
Absent breath sounds, hyperresonance
Pneumothorax
Physical Examination Findings
Findings
Possible diagnosis
Inspiratory stridor, wheezes, retractions
Croup
Stridor, drooling, fever
Epiglottitis
Stridor, wheezing, persistent pneumonia
Foreign body aspiration
Wheezing, flaring, intercostal retractions,
apnea
Bronchiolitis
Sighing
Hyperventilation
Special Investigations
• Chest x-ray PA and lateral
– Lateral neck radiographs (stridor or upper airway obstruction)
• ECG - ischemia, LVH, arrhythmia, troponin-T, enzymes
• Spirometry - asthma or COPD
• Full blood count - infection or anemia
• d-Dimer - pulmonary embolism
• V/Q scan and or spiral computed tomography, pulmonary
angiography
• Bilateral venous doppler
Special Investigations
• Pulse oximetry
• Liver and kidney function tests
• Thyroid functions
• Full lung function tests
• Echocardiogram
• Formal exercise test
Diagnostic Evaluation in Dyspnoea
Possible
diagnosis
Radiography
Pulse oximetry or
spirometry
Other tests
Acute asthma,
COPD exacerbation
Hyperinflated lungs
Decreased O2 sat,
decreased PEFR
and FEV1
-
Pneumonia
Infiltrates, effusion,
consolidation
Decreased or
normal O2 sat
Normal or high WCC
Congestive heart
failure
Interstitial edema,
effusion,
cardiomegaly
Decreased O2 sat
LVH, ischemia, or
arrhythmia on ECG;
low Hb
Pulmonary
embolism
Normal, atelectasis,
pleural effusion,
wedge-shaped
density
Decreased O2 sat
RBBB on ECG;
tachycardia
Pneumothorax
Lung atelectasis,
mediastinal shift
Decreased O2 sat
-
Diagnostic Evaluation in Dyspnoea
Possible
diagnosis
Radiography
Pulse oximetry or
spirometry
Other tests
Croup
Subglottic narrowing
by PA plain film or
CT
Decreased or
normal O2 sat
-
Epiglottitis
Enlarged epiglottis
Decreased or
normal O2 sat
High WCC
Foreign body
aspiration
Visualized foreign
body, air trapping,
hyperinflation
Decreased or
normal O2 sat
Normal or high WCC
Bronchiolitis
Hyperinflation,
atelectasis
Decreased or
normal O2 sat
Normal WCC; RSV
swab
Hyperventilation
Normal
Normal
-
Treatment
• Depends on the specific diagnosis
Acute problem
• Upper airway obstruction or stridor - remove foreign body
• Administer oxygen
• Consider intubation if patient gasping, apnoeic, or non responsive,
following advanced cardiac life support
• Intravenous line access and start administration of fluids and drugs
• Needle/tube thoracentesis in patients with tension pneumothorax
• Administer nebulized bronchodilator if bronchospasm
• Administer IV furosemide if pulmonary edema
• Electrocardioversion if unstable arrhythmia
Treatment
•
Treatment aimed at the underlying cause
•
Cardiac failure
•
Lung disease
•
Severe restrictive lung disease as manifested by pulmonary fibrosis or neuromuscular
abnormality poses a particularly difficult problem
•
In these cases the complaint is often permanent and debilitating
•
The most effective treatment of dyspnoea in cases of far-advanced pulmonary
fibrosis is single lung transplantation
•
In advanced emphysema lung volume reduction surgery has been tried to relieve
dyspnoea by reducing FRC, which reduces the work of breathing by improving the
mechanical function of the lungs and diaphragm
Treatment
• Opiates and benzodiazepines have been tried in intractable
dyspnoea especially malignant disease
• Anecdotal reports indicate some short-term value
• Clinical trials failed to confirm long-term benefit
• Some studies have demonstrated deleterious events
When to Refer
• Many patients with dyspnoea can be evaluated and treated without
referral to a specialist
• Unexplained dyspnoea after routine evaluation usually warrants
referral
• When full pulmonary function testing or echocardiography or
cardiopulmonary exercise testing required warrants referral
Medico-Legal Considerations
• Acute dyspnoea can be associated with life-threatening diseases
such as pulmonary embolism and myocardial infarction
• Failure to promptly and accurately pursue these diagnoses in
patients with unexplained dyspnoea can lead to untimely deaths and
subsequent lawsuits
Summary of Evaluation
History and Examination
Evidence of cardiopulmonary or
other disease
FBC, CXR, ECG, Spirometry
Asthma, COPD, Chronic HF,
cardiomegaly, HT, Anaemia
U&E, Liver Function tests
Liver or Renal Disease
Full LFT’s, Echocardiogram
Restrictive lung disease, valvular heart
disease, LV dysfunction
Exercise Test
Occult coronary artery disease,
asthma
Conclusion
An approach to dyspnoea requires:
•
•
•
•
•
•
•
Stepwise approach
Beginning with a careful medical history
Physical examination
Appropriate investigations
Specific diagnosis
Treat condition
Refer