Dyspnea Chang Shim MD Pulmonary Division Jacobi Medical

Dyspnea Chang Shim, MD Pulmonary Division Jacobi Medical Center

Dyspnea Definition: Unpleasant or uncomfortable respiratory sensations A subjective experience of breathing discomfort. The experience derives from interactions among multiple physiological, psychological, social and environmental factors.

Dyspnea Common complaint among the general population. 6%-27% of different gender and age strata (37 -70 yrs) in the Framingham Study 2. 7% of the emergency room visits Most common: asthma, myocardial dysfunction, COPD, interstitial lung disease

American Thoracic Society Shortness of Breath Scale Grade Degree 0 none 1 mild Description No trouble walking up a slight hill SOB hurrying on the level or walking up a slight hill 2 moderate Walks slower than the peers; has to stop for SOB walking at own pace 3 severe Stops for breath after walking about 100 yards or after a few minutes 4 very severe Too breathless to leave the house or breathless on dressing or undressing

Dyspnea: Direct Measurement Visual Analog Scale Not breathless-----------------------Extremely breathless Modified Borg Scale 0 0. 5 1 2 3 4 5 7 9 10 none very, very slight Moderate somewhat severe Severe very severe very, very severe maximal

Physiologic Categories of Diseases Causing Dyspnea-1 Mechanical interference with ventilation Obstruction of airflow Asthma, emphysema Endobronchial tumor Tracheal stenosis Stiff lungs Interstitial fibrosis LV failure Lymphangitic carcinoma Resistance to expansion of the chest wall or diaphragm Obesity Pleural thickening Kyphoscoliosis Abdominal mass, ascites, pregnancy

Physiologic Categories -2 Weakness of the respiratory pump Absolute Prior polio Neuromuscular disease- Guillain-Barre syndrome Myasthenia gravis, muscular dystrophy, SLE, Hyperthyroidism, hypothyroidism, multiorgan dysf Relative Pleural effusion Pneumothorax Hyperinflation (emphysema)

Physiologic Categories -3 Increased respiratory drive Hypoxia Metabolic acidosis Stimulation of intrapulmonary receptorsinfiltrative lung disease, pulmonary hypertension, pulmonary edema

Physiologic Categories-4 Wasted ventilation Capillary destruction: emphysema, interstitial lung disease Large vessel obstruction: pulmonary embolism, pulmonary vasculitis Psychological dysfunction Anxiety-panic state, depression, litigation

Mechanisms of Dyspnea Originates with the activation of sensory systems involved with respiration. Relayed to the higher brain centers for processing of respiratory-related signals and cognitive and behavioral influences shape the ultimate sensation.

Evaluation of the Patient with Dyspnea History and physical examination: characteristics of symptoms, quality, intensity, duration, distress. Specific activities associated with dyspnea Quantify intensity of dyspnea Effect on life quality Cardiovascular vs pulmonary dyspnea, or both

Special Studies-1 Pulmonary function studies Lung volumes and flow rates Diffusing capacity (DLCO) Arterial blood gases Cardiopulmonary exercise testing Bronchial challenge Maximal inspiratory pressure

Special Studies-2 Imaging studies Ventilation-perfusion lung scan Chest CT, HRCT (high resolution CT) Gallium scanning Diaphragmatic fluoroscopy

Special Studies-3 Cardiac evaluation Echocardiogram-for ventricular size and function, regional wall motion abnormalities Dobutamine stress echocardiography-regional wall motion abnormalities. Thallium perfusion scan Holter monitor Cardiac catheterization/coronary angiography Plasma BNP or N-terminal pro-BNP most HF patients >400 pg/ml; normals 10 pg

Special Studies-4 Sleep studies Esophageal p. H monitor ENT examination Psychological assessment

Treatment of Dyspnea Altered Central Perception Cognitive-behavioral strategies Perception of dyspnea results in part from the effects of cognitive, emotional, and behavioral factors on the conscious awareness of the demand to breathe and the affective response to the symptom. Education about the disease process Teaching of the coping skills, for example, relaxation, distraction, reassurance

Asthma • Reverse airflow obstruction – Bronchodilators, anti-inflammatory agents • Relieve chest tightness – Same as above • Control cough – Same, + cough meds & local anesthetics • Relieve anxiety – Anxiolytics: usually contraindicated – Rare exceptions: benzodiazepines, opiates

Reduce Resistive Load Reverse bronchoconstriction. Decrease airway inflammation and edema Pharmacological therapy Inhaled beta 2 -agonists, short and long-act Inhaled anticholinergics Theophylline probably related to deceased operational lung volumes.

COPD • Reverse airflow obstruction: anti-cholinergics (short and long acting), corticosteroids, long acting beta agonists, theophylline • Reverse hyperinflation/air trapping – Inhalation meds, Expiratory maneuvers, LVRD • Exercise rehabilitation

COPD • LVRS (lung volume reduction surgery): NETT • Oxygen • NIPPV for acute exacerbation • Reduce ventilatory requirements: metabolism, V/Q, exercise rehab. • Central drive: depressants: benzodiazepines, opiates

Treatment of Dyspnea Reduce ventilatory demand Increased VE or VE/MVC (maximal ventilatory capacity) correlates with exertional dyspnea. Reduce CO 2 output, VD/VT (physiologic dead space), arterial hypoxemia, metabolic acidosis. Hyperventilation itself causes dyspnea.

Reducing Metabolic Load Exercise training Improves aerobic capacity Reduces rate of rise of lactate levels with exercise Decreases exertional dyspnea Improves exercise tolerance Reduces VE per work rate primarily by decreasing breathing frequency. VCO 2 and VO 2 reduced at a given work rate=improved efficiency.

Reducing Metabolic Load Supplemental oxygen during exercise Patients with chronic lung disease have reductions in blood lactate and VE

Decreasing Central Drive Inhaled pharmacologic therapy Lidocaine may alter afferent information from the pulmonary receptors: Asthma Low dose opiates via nebulizers ? Fans: mechanoreceptors on the face or decrease in temperature of facial skin Improve efficiency of CO 2 elimination VD/VT is increased. Slow deep breath Altered breathing pattern: slow deep breathing, diaphragmatic breathing, pursed lip breathing

Decreasing Central Drive Oxygen Therapy Depress hypoxic drive from the peripheral chemoreceptors in the carotid body. Oxygen may blunt pulmonary artery pressure rise with exercise. Oxygen may improve ventilatory muscle function. Airflow over the face or nasal mucosa may ameliorate dyspnea.

Decreasing Central Drive Oxygen Therapy As an adjunct to exercise training program. Prevents skeletal muscle deconditioning by increasing ADL. Criteria: PO 2 =<55 mm. Hg or 56 -59 mm. Hg with polycythemia or cor pulmonale. Flow rate should be adjusted to correct hypoxemia. Delivery by nasal canula, face mask, transtracheal catheter

Decreasing Central Drive Pharmacologic therapy Opiates Respiratory depressants reduce the central processing of neural signals. Reduce VE & VO 2 at rest and exercise. Endogenous opioids modulate dyspnea in acute bronchoconstriction. Opiates may alleviate dyspnea by blunting perception. Side effects: hypercapnea, altered mental status, constipation, nausea, vomiting, drowsiness Inhaled opiates are not effective.

Decreasing Central Drive Anxiolytics May relieve dyspnea by depressing hypoxic or hypercapnic ventilatory responses. May alter emotional responses to dyspnea. Benzodiazepines failed to demonstrate consistent improvement in dyspnea. Poorly tolerated. May benefit individuals with respiratory panic attacks, but needs close monitoring.

Reducing Ventilatory Impedance Reduce lung hyperinflation Dynamic hyperinflation during exercise or hyperventilation—auto-PEEP or intrinsic PEEP is important contributor to dyspnea. Surgical volume reduction Unilateral bullectomy, or lung volume reduction surgery (LVRS) benefits by reduction of operating lung volumes. Dyspnea decreased by reduced dynamic hyperinflation, improved chest wall mechanics and increased lung recoil and increased airflow.

Lung Volume Reduction Surgery in Emphysema

Lung Volume Reduction Surgery

Continuous positive airway pressure (CPAP) Low levels of CPAP relieve dyspnea in Acute bronchoconstriction in asthma, Patients weaning from mechanical ventilation, During exercise in advanced COPD. Benefits of CPAP are probably related to reduction in auto PEEP

Improving Inspiratory Muscle Function Strength and Endurance Respiratory muscle weakness, fatigue and dyspnea Decreased body weight—decreased diaphragm mass, decreased intercostal muscle fiber size Weight loss of >10% of ideal body weight Improvement of respiratory muscle function with enteral or parenteral nutrition Inspiratory muscle training? Positioning: leaning forward position Partial ventilatory support Minimizing the use of steroids

Obesity • Apple shaped, in contrast to pear shaped, is more burdensome to diaphragmatic movement. • Central respiratory drive: supernormal • Upper airway dimension: crowded, relaxed muscle • Airway dimension is related to lung volume. • Upright position, unloading of the diaphragm • CPAP (continuous positive airway pressure) prevents large airway collapse • Bariatric surgery

Paralysis, Chest wall abnormality Reversible conditions, myasthenia, Guillain Barre: mechanical ventilation until recovery of neuro-muscular function Correct chest wall abnormality if feasible: pleural effusion, pneumothorax, flail chest NIPPV

Diagnosis of Diaphragmatic Paralysis Unilateral: often asymptomatic VC sitting and supine Sniff test under fluoroscopy Sonography

Sniff Test Not the cocaine variety Sniff is a potent, brief inspiratory maneuver everyone is familiar with. Monitor diaphragmatic movement (fluoroscopic imaging) from the patient’s side during sniffing. The paralyzed diaphragm moves up paradoxically while the intact diaphragm descends sharply.

Dyspnea in Diaphragm Paralysis Body position or posture Exercise tolerance Stretch receptors in the muscles and tendons Activities: rest, sleep, exertion

Diaphragm Pacer

Hyperventilation Syndrome • Anxiety-panic attacks • Shortness of breath, tingling in finger tips, circum-oral numbness, dry mouth, globus hystericus, sense of doom. • In association with asthma, COPD, vocal cord dysfunction: management problem (beta agonist). • Important to dissociate asthma from hyperventilation: PEFR, paper bag rebreathing, slow expiratory maneuvers to prevent hyperventilation, ex. shee. • Pharmacologic: narcotics, benzodiazepines • Self-corrected once patient lapses into coma

END

Dyspnea Assessment Borg scale for severity Sensation: inability to inhale deeply inability to exhale properly Hyperinflation or air trapping in obstructive lung disease Position or posture, helpful, detrimental Bending over vs tripod positions in adults

Dyspnea in Obesity Position or posture Activity Walking, climbing stairs Bending over Supine position with choking sensation Lateral decubitus with pendulous belly is better tolerated.

Dyspnea with CHF Receptors for dyspnea in J receptors or airway or stretch receptors in left atrium Small airways dysfunction from peribronchial edema. Interstitial vs alveolar space edema Oxygen desaturation

Decreasing Central Drive Pharmacologic therapy Opiates Respiratory depressants reduce the central processing of neural signals. Reduce VE & VO 2 at rest and exercise. Endogenous opioids modulate dyspnea in acute bronchoconstriction. Opiates may alleviate dyspnea by blunting perception. Side effects: hypercapnea, altered mental status, constipation, nausea, vomiting, drowsiness Inhaled opiates are not effective.

Decreasing Central Drive Anxiolytics May relieve dyspnea by depressing hypoxic or hypercapnic ventilatory responses. May alter emotional responses to dyspnea. Benzodiazepines failed to demonstrate consistent improvement in dyspnea. Poorly tolerated. May benefit some individuals with respiratory panic attacks, but need close monitoring.

Reducing Ventilatory Impedance Reduce lung hyperinflation Dynamic hyperinflation during exercise or hyperventilation—auto-PEEP or intrinsic PEEP is important contributor to dyspnea. Surgical volume reduction Unilateral bullectomy, or lung volume reduction surgery (LVRS) benefits by reduction of operating lung volumes. Dyspnea decreased by reduced dynamic hyperinflation, improved chest wall mechanics and increased lung recoil and increased airflow.

Continuous positive airway pressure (CPAP) Low levels of CPAP relieve dyspnea in Acute bronchoconstriction in asthma, Patients weaning from mechanical ventilation, During exercise in advanced COPD. Benefits of CPAP are probably related to reduction in auto PEEP

Improving Inspiratory Muscle Function Strength and Endurance Respiratory muscle weakness, fatigue and dyspnea Decreased body weight—decreased diaphragm mass, decreased intercostal muscle fiber size Weight loss of >10% of ideal body weight Improvement of respiratory muscle function with enteral or parenteral nutrition Inspiratory muscle training? Positioning: leaning forward position Partial ventilatory support Minimizing the use of steroids

Obesity • Apple shaped, in contrast to pear shaped, is more burdensome to diaphragmatic movement. • Central respiratory drive: supernormal • Upper airway dimension: crowded, relaxed muscle • Airway dimension is related to lung volume. • Upright position, unloading of the diaphragm • CPAP (continuous positive airway pressure) prevents large airway collapse • Bariatric surgery

Paralysis, Chest wall abnormality Reversible conditions, myasthenia, Guillain Barre: mechanical ventilation until recovery of neuro-muscular function Correct chest wall abnormality if feasible: pleural effusion, pneumothorax, flail chest NIPPV

Hyperventilation Syndrome • Anxiety-panic attack • Shortness of breath, tingling in finger tips, circumoral numbess, dry mouth, globus hystericus, sense of doom. • In association with asthma, COPD, vocal cord dysfunction: management problem (beta agonist). • Important to dissociate asthma from hyperventilation: PEFR, paper bag rebreathing, slow expiratory maneuvers to prevent hyperventilation, ex. shee. • Pharmacologic: narcotics, benzodiazepines • Self-corrected once patient lapses into coma.

Dyspnea Assessment Borg scale for severity Sensation: inability to inhale deeply inability to exhale properly Hyperinflation or air trapping in obstructive lung disease Position or posture, helpful, detrimental Bending over vs tripod positions in adults

Dyspnea in Obesity Position or psture Activity Walking, climbing stairs Bending over Supine position with choking sensation Lateral decubitus with pendulous belly is better tolerated

Dyspnea with CHF Receptors for dyspnea in J receptors or airway or stretch receptors in left atrium Small airways dysfunction for peri-bronchial edema. Interstitial vs alveolar space Oxygen saturation

Improving Inspiratory Muscle Function Strength and Endurance Respiratory muscle weakness, fatigue and dyspnea Decreased body weight—decreased diaphragm mass, decreased intercostal muscle fiber size Weight loss of >10% of ideal body weight Improvement of respiratory muscle function with enteral or parenteral nutrition Inspiratory muscle training? Positioning: leaning forward position Partial ventilatory support Minimizing the use of steroids

Obesity • Apple shaped, in contrast to pear shaped, is more burdensome to diaphragmatic movement. • Central respiratory drive: supernormal • Upper airway dimension: crowded, relaxed muscle • Airway dimension is related to lung volume. • Upright position, unloading of the diaphragm • CPAP (continuous positive airway pressure) prevents large airway collapse • Bariatric surgery

Paralysis, Chest wall abnormality Reversible conditions, myasthenia, Guillain Barre: mechanical ventilation until recovery of neuro-muscular function Correct chest wall abnormality if feasible: pleural effusion, pneumothorax, flail chest NIPPV

Hyperventilation Syndrome • Anxiety-panic attacks • Shortness of breath, tingling in finger tips, circumoral numbess, dry mouth, globus hystericus, sense of doom. • In association with asthma, COPD, vocal cord dysfunction: management problem (beta agonist). • Important to dissociate asthma from hyperventilation: PEFR, paper bag rebreathing, slow expiratory maneuvers to prevent hyperventilation, ex. shee. • Pharmacologic: narcotics, benzodiazepines • Self-corrected once patient lapses into coma.

Dyspnea Assessment Borg scale for severity Sensation: inability to inhale deeply inability to exhale properly Hyperinflation or air trapping in obstructive lung disease Position or posture, helpful, detrimental Bending over vs tripod positions in adults

Dyspnea in Obesity Position or psture Activity Walking, climbing stairs Bending over Supine position with choking sensation Lateral decubitus with pendulous bellybetter tolerated

Physiologic Categories of Diseases-3 Increased respiratory drive Hypoxia Metabolic acidosis Stimulation of intrapulmonary receptorsinfiltrative lung disease, pulmonary hypertension, pulmonary edema

Physiologic Categories-4 Wasted ventilation Capillary destruction: emphysema, interstitial lung disease Large vessel obstruction: pulmonary embolism, pulmonary vasculitis Psychological dysfunction Anxiety, depression, litigation

Dyspnea with CHF Receptors for dyspnea in J receptors or airway or stretch receptors in LA Small airways dysfunction for peri-bronchial edema. Interstitial vs alveolar space Oxygen saturation

Dyspnea with CHF Receptors for dyspnea in J receptors or airway or stretch receptors in LA Small airways dysfunction for peri-bronchial edema. Interstitial vs alveolar space Low p. O 2, low cardiac output, tissue acidosis, pulmonary interstitial pressure

Dyspnea and circumstances Effect of Anxiety on respiratory sensation Anxiety provoked from dyspnea Interactions of anxiety and dyspnea Asthma and panic attacks Asthma and vocal cord dysfunction