This document outlines an approach to evaluating and diagnosing dyspnea. It begins by defining dyspnea and noting its high prevalence. Types of dyspnea like orthopnea and paroxysmal nocturnal dyspnea are described. The diagnostic approach involves obtaining a detailed history regarding onset, duration, patterns and associated symptoms. A physical exam assesses respiratory effort, oxygenation, and signs of heart failure. Initial tests may include EKG, chest x-ray, and bloodwork. Further tests are guided by initial findings and may include echocardiogram, pulmonary function tests, CT, or arterial blood gas. Treatment focuses on the underlying cause identified through diagnosis.
2. Introduction
Dyspnea is one of the most common presenting symptoms
encountered by clinicians.
Dyspnea has been reported in 50% of patients admitted
to acute, tertiary care hospitals and in 25% of patients
in ambulatory settings. Data from population-based
studies have shown that the prevalence of mild to
moderate dyspnea ranged from 9%-13% in adults.This
figure ranged from 15%-18% in adults aged 40 years or
older; and 25%-27% in persons aged 70 years or more.
3. Definition
subjective experience of breathing discomfort that consists of
qualitatively distinct sensations that vary in intensity.The
experience derives from interactions among multiple
physiological, psychological, social, and environmental factors
and may induce secondary physiological and behavioral
responses.
Am J Respir Crit Care Med 1999; 159:321-40.
9. Types of dyspnea
Orthopnea - dyspnea on lying flat and is a sign
of advanced heart failure. Lying flat increases venous
return and in patients with left ventricular impairment
may precipitate pulmonary edema.The severity can be
graded by the number of pillows used at night, e.g.
‘three-pillow orthopnea’
10. PND -sudden breathlessness waking the patient from sleep. It
is caused by accumulation of alveolar fluid. Patients
may choke or gasp for air, sit on the edge of the bed and
open windows in an attempt to relieve their distress
11.
12. Platypnea (platypnoea–orthodeoxia syndrome)-
breathlessness on sitting upright with relief
on lying down is rare and due to right-to-left shunting
through a patent foramen ovale, atrial septal defect or a
large intrapulmonary shunt. It is much rarer than orthopnea
and is usually associated with deoxygenation
13. Trepopnea- Breathlessness when lying on one side is due to
unilateral lung disease (patient prefers the healthy lung
down), dilated cardiomyopathy (patient prefers right side
down) or tumours compressing central airways and major
blood vessels
17. Cardiac vs Pulmonary dyspnea
Cough not prominent after dyspnea
Orthopnea common
PND common
Edema
Raised JVP
Evidence of valvular heart defect
Reduced urine output
Benefit with diuretics
Cough prominent precedes dyspnea
No orthopnea
Sputum production and wheezing
No PND
Normal urine output
No change with diuretics
18. Diagnostic approach
# History
Onset -sudden onset (acute pulmonary thromboembolism, acute
coronary syndrome or spontaneous pneumothorax, acute
respiratory distress syndrome (ARDS), foreign body
aspiration, psychogenic causes should be high in the list of
differential diagnosis.
Duration - slowly progressing over hours or days include bronchial
asthma, chronic obstructive pulmonary disease (COPD), pleural
effusion, pneumonia, congestive heart failure, small pulmonary
emboli, interstitial lung disease or malignancy; psychogenic
causes; and cardiac diseases like coronary artery disease,
congestive heart failure
19. Pattern –
Prolonged bed rest prior to acute onset dyspnoea may
indicate acute pulmonary embolism.
Orthopnea
PND
platypnoea-orthodeoxia
Trepopnea
20. Variations –
Intermittent episodes-bronchial asthma, heart failure, pleural
effusion, recurrent pulmonary embolism, gastro-oesophageal
reflux disease; aspiration, cardiovascular dz, exercise indused.
Seasonal or diurnal - bronchial asthma, Aggravation of
dyspnoea during winter months may occur with COPD.
22. Physical examination
Whether the patient is able to complete full sentences
while talking.
Use of accessory muscles of respirations.
paradoxical breathing or sitting in tripod position
Signs of pallor, cyanosis, clubbing and pedal oedema are looked
Haemodynamic stability
whether the patient is able to maintain saturation on room air is
assessed using pulse oximetry.
23. measuring blood pressure pulsus paradoxus should be
watched for as its presence points to pericardial disease,
restrictive heart disease.
the symmetry of chest wall movements with respiration is
observed
Percussion (e.g., dull note in pleural effusion, hyperresonant in
tension pneumothorax).
auscultation (wheeze, crepitations, decreased or
hyperreasonant sounds, bronchial breath sounds).
24. signs of heart failure should
Elevated jugular venous pressure (JVP),
peripheral oedema,
S3 gallop rhythm,
presence of murmurs
Paradoxical inward movement of abdominal muscles indicate
weakness of diaphragm.
25. investigation
Electrocardiogram should be obtained immediately if
history and physical examination are in favour of heart
failure, acute coronary syndrome, cardiac arrhythmias,
pulmonary embolism or pulmonary hypertension.
chest radiograph computed tomography of the chest, and bedside
thoracic ultrasonography are helpful in diagnosing
pleural effusions, pulmonary oedema, pneumothorax
or consolidation
Thoracic ultrasonography is emerging
as a point-of-care diagnostic test recently
26. Lung ultrasonography with or without testing for N-terminal
pro-brain natriuretic peptide (NT-proBNP) has high
diagnostic accuracy for differentiating acute dyspnoea
due to heart failure from COPD/bronchial asthma-related
acute dyspnoea in prehospital/ER seting.
Complete haemogram (anaemia) renal functions and
serum electrolytes help in identifying kidney disease
27. Arterial blood gas (ABG) analysis will help in knowing
the type of respiratory failure and also gives information
about the acid-base state of the patient
cardiac biomarkers lik troponin,
D-dimer
N-terminal pro-brain natriuretic peptide (NT-proBNP)
exercise testing
Pulmonary function testing including spirometry.
Reversibility testing,
diffusion capacity of lung for carbon monoxide
28. TREATMENT
Depending the initial aetiological clues, further diagnostic
work-up is planned and the patient is administered
appropriate specifc treatment accordingly