Good Morning!

I am Dr. Farjad IkramHouse Officer, Cardiology, Shalamar Hospital

DYSPNEA

Case Scenario

1

Biodata× Mr. Arshad Khan× 60 years / Male× Retired, married× Weight 80 kg× Height 152 cm

Past history× Anterior wall

STEMI- 4 years ago, SK

given× Diabetes for 15

years× Ex-smoker

E.R presentationShortness of breath- for 4 hours, on

restOrthopnea, PNDVitals× Pulse – 100 b/m- regular,

bounding× B.P – 100/50

mmHg× Resp. Rate – 30

b/m× SpO2 – 90%× Afebrile× BSR – 240 mg/dl

Examination× Raised JVP× Bipedal pitting edema× Apex beat 6 ICS, left

AAL× S1 + S2 + PSM× Bibasilar rales (fine)× Rt. subcostal

tenderness× GCS 15/15

Investigations ordered× Troponin I× 12 lead ECG× Chest X-ray PA view× Echocardiography

Case Scenario

Etymology, Etiology and Epidemiology

2

Definition

×Dyspnea is an uncomfortable sensation or awareness of breathing.

×The term is used interchangeably with:• Shortness of breath• Difficulty in breathing• Breathlessness

“Dyspnea is a term used to describe subjective experience of breathing

discomfort that consists of qualitatively distinct sensations that

vary in intensity.- American Thoracic Society

“×These distinct sensations include:• increased effort for breathing• chest tightness• air hunger (feeling of not enough

oxygen)- American Thoracic Society

3-6% E.R visits

30 % cases are multi-factorial

15-20% hospital admssions

Etiology

×Dyspnea is a normal symptom of heavy exertion.

×Dyspnea becomes pathological if it occurs in unexpected situations, on light exertion, or at rest.

×It is a symptom of many organ systems, especially cardiovascular and respiratory causes.

Etiology×In 85% of the cases it is due to:• Asthma• Pneumonia• Ischemic heart disease• Interstitial lung disease• Congestive heart failure• COPD• Psychogenic causes

Pathophysiology

3

PathophysiologyDyspnea results when a stimulus activates the respiratory center

beyond a certain threshold

“The Downward Spiral”

Respiratory rateand distress

4

Tachypnea×Tachypnea is rapid breathing (respiratory rate is > 20 breaths per

minute)• Causes: exercise, labor in pregnancy, CO poisoning, pneumonia in

children• Children have higher resting resp. rate that decline rapidly by first 3 yrs

of life×Hyperpnea is breathing that is more rapid and deeper, than at

rest• Physiologic - after heavy exertion, high altitude• Pathologic - anemia, sepsis, metabolic acidosis×Hyperventilation (over-breathing) so that PCO2 is decreased • Hypocapnia leads to respiratory alkalosis (tingling, dizziness, weakness,

tetany, nausea, vomiting)×Kussmaul breathing is rapid, deep, laboured breathing seen

with worsening metabolic acidosis i.e. diabetic ketoacidosis, kidney failure

Bradypnea×Apnea is cessation of breathing• Sleep apnea – pauses in breathing 20-30 times per hour during sleep• Apnea of prematurity – pauses in breathing in premature infants for >20

sec×Bradypnea is breathing that is more rapid and deeper, than at

rest• A rate of < 12 breaths for age >12 years×Hypopnea is bradypnea with overly shallow breathing than at

rest• Causes – sedatives, alcoholism, adenoiditis, aging, obesity, hypo-

thyroidism, hypokalemia, neuromuscular diseases (GB syndrome, myasthenia, ALS)

×Hypoventilation (under-breathing) so that PCO2 is increased • Hypercapnia leads to respiratory acidosis (headache, anxiety, confusion,

blurred vision). Hypoventilation can lead to hypoxia.

Respiratory Distress×Respiratory distress• Physical presentation of respiratory distress is “labored breathing”• Subjective sensation or awareness of respiratory distress is

“dyspnea”

×Examples:• Adults – Acute Respiratory Distress Syndrome (ARDS)• Premature infants – Infant Respiratory Distress Syndrome (IRDS) also called Hyaline Membrane Disease due to surfactant deficiency

Paraoxysmal Nocturnal Dyspnea

×Paraoxysmal nocturnal dyspnea (PND)• attacks of severe dyspnea that occur suddenly during sleep

hours,• causing the person to wake and sit up,• associated with cough and wheeze

×Pathophysiology of PND• In horizontal position, there is redistribution of blood from lower

extremities into the pulmonary circulation• In patients who have already reduced pulmonary compliance and

left ventricular dysfunction, will develop pulmonary congestion• Congestion decreases when patient assumes a more erect

position

Differentials

5

PULMONARYCARDIAC MIXEDNON

CARDIOPULMONARY

Causes of dyspneacan be divided into four categories

Cardiac causes× Congestive heart failure× Ischemic heart disease× Valvular dysfunction× Cardiomyopathies× Pericardial diseases× Tachydysrhythmias× Congenital heart disease

Congestive Heart Failure

Pulmonary causes× COPD and astma excacerbations× Lower RTI× Restrictive lung diseases× Interstitial lung diseases× Bronchiectasis and emphysema× Pneumothorax× Pleural effusion, Hemothorax, Pyothorax

Mixed cardio-pulmonary causes

× COPD with pulmonary HTN and cor pulmonale× Chronic pulmonary emboli× Deconditioning (decreased physical activity)× Trauma

Non-cardiopulmonary causes× Metabolic acisosis (DKA, sepsis, renal failure)× Oto-rhino-laryngeal disorders× Neuromuscular disorders (GBS, ALS, MG, dystrophies)× Respiratory depression (opiates, benzodiazepines)× Hematologic disorders (anemias, polycythemia, ACS)× Psychiatric disorders (anxiety, panic disorders)× Other: obesity, cirrhosis, thyrotoxicosis, CO poisoning,

anaphylaxis

History

6

History Evaluation×Chronicity×Onset×Positionality×Severity×Associated symptoms×Past medical and surgical history×Past gynecological and obstetric history×Family history×Occupational history×Drug use / abuse history×Social history (smoking, alcoholism)

acute(in matter of minutes)

sub-acute(over hours to

days)

chronic(over weeks to

months)

History - Chronicity

History - ChronicityACUTE

(in matter of minutes)SUB-ACUTE

(over hours to days)CHRONIC

(over weeks to months)Acute pulmonary embolism Pulmonary edema Congestive heart failureAcute coronary syndrome COPD exacerbation COPD

Acute asthma exacerbation Lower RTI Chronic pulmonary emboliAcute heart valve

insufficiencyPleural effusion Valvular heart disease

Pneumothorax Sepsis Renal failureForeign body aspiration Diabetic ketoacidosis Interstitial lung diseases

Acute anxiety Myocarditis/Pericarditis CardiomyopathiesCardiac tamponade Cardiac tamponade Neuromuscular disorders

Paroxysmal tachydysrhythmias Thyrotoxicosis TuberculosisAnaphylaxis, Ascites,

CirrhosisGuillain Barre syndrome Obesity, Deconditioning

History - Onset×Dyspnea on exertion• i.e. IHD, CHF, valvular insufficiency, interstitial lung disease etc×Dyspnea on rest• i.e. ACS, severe anxiety, acute asthma exacerbation etc×Any triggers• i.e. recent trauma, emotional stress, cold, wind, dust, mould, drugs, any

new pets or plants, smoke inhalation, any phobias×Any diurnal variation• i.e. PND is seen in CHF×Any seasonal variation• i.e. seasonal variant asthma

History - Positionality×Orthopnea – dyspnea which occurs when lying supine Seen with pulmonary edema i.e. due to left ventricular failure×Platypnea – dyspnea that is relieved by lying down×Orthodeoxia – low oxygen saturation in upright position×Platypnea – Orthodeoxia syndrome Seen in postional right-to-left shunt (ASD, PFO), constrictive pericarditis,

severe V/Q mismatch (mutliple pulmonary emboli), hepatopulmonary synd.

×Trepopnea – dyspnea sensed while lying on one side but not the other

Seen in heart failure, or due to disease of one lung / bronchus / pleura (i.e. unilateral pleural effusion)

History - Severity×Severity of dyspnea is subjective to the perception of the patient.×It is important to establish degree of severity of dyspnea in

patients with chronic causes like heart failure, COPD or interstitial lung disease, as these can affect the quality of life.

×We can use the following scales:• New York Heart Association (NYHA) functional classification - used mainly for patients with heart failure• Medical Research Council (MRC) scale - used mainly for patients with COPD• Veterans Specific Activity Questionnaire (VSAQ) - estimates aerobic capacity in meters

NYHA Class

MRC scale

History – Associated symptomsChest pain

Pleuritic chest painChest tenderness

FeverCough

SputumHemoptysis

StridorCoryza

WheezePalpitations

HeadacheSyncope

Diaphoresis

• Dizziness• Dysphagia• Nausea, vomiting• Altered bowel habits• Fatigue• Gen. weakness• Gen. swelling• Myalgia, arthralgia• Abdominal pain• Weight loss• Decreased appetite• Blurred vision• GI bleed• Rash

History – Misc.×Past medical history• any medical conditions, past admissions, recent trauma or immobilization

etc×Past surgical history• any major operations, history of difficult intubation or catheterization etc×Past gynecological and obstetric history• menstrual history, current or recent pregnancy and related complications

etc×Family history• IHD, sudden cardiac death, TB, asthma, cancer, hematologic disorders

etc×Occupational history• long standing/sitting hours, pneumoconiosis, carcinogen exposure etc×Drug use and abuse history• sedatives (narcotics, benzodiazepines), beta blockers, contraceptives etc×Personal history - diet, exercise, smoking, alcohol consumption

Dyspnea features in common diseases

Examination

7

General physical examination

Sign Seen in• Pyrexia pulmonary embolism (PE), infections• Clubbing COPD, cirrhosis, lung cancer, ILD, pulmonary AV fistulas• Cyanosis COPD, PE, foreign body aspiration, congenital heart diseases• Jaundice liver failure, leptospirosis, hemolytic anemia• Goitre thyrotoxicosis, airway obstruction• Cold peripheries hypotension• Facial edema superior vena cava syndrome, anaphylaxis• Lower limb edema CHF, volume overload, MI, arrhythmias, valvular insufficiency• Urticarial rash anaphylaxis

• Calf pain/tenderness DVT (Homans sign)

Cardiovascular examinationSign Seen in

• Hypotension PE, MI, acute valvular insufficiency, cardiac tamponade, sepsis• Hypertension hypertensive heart failure, hyperthyroidism, pheochromocytoma• Pulsus paradoxus asthma, COPD, cardiac tamponade• Loud S2 pulmonary hypertension, cor pulmonale• Irregular heart beat tachydysrhythmias• Murmurs valvular insufficiency• Pericardial rub pericarditis• Muffled heart sounds cardiac tamponade• Engorged neck veins CHF, pneumothorax, tamponade• Kussmaul’s sign increased JVP on inspiration in constrictive pericarditis

Respiratory examinationSign Seen in

• Pursed lip breathing COPD• Laryngeal descent COPD• Stridor upper airway obstruction • Hoarseness laryngitis, laryngeal tumours, vocal cord paralysis• Kyphoscoliosis restrictive lung disease, neuromuscular disorders• Barrel chest emphysema, cystic fibrosis• Tracheal deviation away from affected side in tension pneumothorax, hemothorax,

pleural effusion• U/L dull percussion pleural effusion, atelectasis, pneumonia, F.B aspiration• Hyper-resonance pneumothorax, severe emphysema

Chest ascultationSign Seen in

• Reduced breath sounds

pleural effusion, atelectasis, F.B aspiration, pneumothorax

• Wheezing asthma, COPD, CF, anaphylaxis, PE, pulmonary congestion• Fine rales pulmonary edema (bibasal), • Coarse rales pneumonia• Velcro crackles interstitial lung disease• Pleural rub pleurisy

Neurological examinationSign Seen in

• B/L progressive limb weakness with hyporeflexia

Guillain–Barré syndrome

• Cranial nerve palsies CNS infections, botulism• Ptosis myasthenia gravis, myotonic dystrophy, botulism• Pinpoint pupils opiate overdose• Altered mental state • hypoxaemic resp. failure related to CHF, pulmonary edema

• asthma, COPD, pneumonia• sepsis, CNS infections

Investigations

8

PERC Rule×Low clinical pre-test probability×Plus:• Age < 50 years• Pulse < 100 b/m• SpO2 > 94%• No leg swelling• No hemoptysis• No recent trauma / surgery• No prior PE / DVT• No hormone use

8,138 patientsSensitivity 97.4 %

False negative 0.9 %

Diagnostic tests×Nearly in all patients- Pulse oximetry- 12 lead ECG- Chest X-ray

×In selected patients- Complete blood count (CBC)- Arterial blood gaes (ABGs)- Peripheral blood picture- Peak flow spirometry- Cardiac biomarkers- D-dimer- Brain natriuretic peptide (BNP)- Echocardiography- Ultrasound abdomen and pelvis- CT angiography (coronary)- CT angiography (pulmonary)

D-dimer×A fibrin degrataion product (FDP)- released after a blood clot undergoes fibrinolysis×Its blood levels are raised in- thromboembolic conditions- pro-thrombotic conditions×A negative test is useful in ruling out the following:- Deep venous thrombosis (DVT)- Pulmonary embolism (P.E)- Ischemic stroke- Disseminated intravascular coagulation (DIC)×A positive test warrants further investigation for underlying

causes

ELISA D-dimer

Sensitivity 96 %Specificity 45 %

Brain natriuretic peptide×BNP is secreted by heart ventricles in repsonse to excessive stretching of cardiomyocytes×PreproBNP ProBNP BNP + NT-proBNP×Physiologic actions of BNP are:- vasodilation (decrease systemic vascular resistance)- natriuresis and diuresis (reduction in blood volume)×Net effect – decrease cardiac output and blood pressure×Useful in differentiating heart failure from other causes of

dyspnea- Normal BNP levels ( < 100 pg/ml ) rule out acute heart failure- Raised levels ( > 500 pg/ml ) are not useful in diagnosis of acute HF- Raised levels are useful in prognosis in heart failure

Sensitivity 100 %

Specificity 85 %

Half life 20 m

Thanks!

Any questions?