Management of Dyspnea/Breathlessness for the Medical and Hematological Oncologist

Transcription

1 Management of Dyspnea/Breathlessness for the Medical and Hematological Oncologist Author: Jeff Myers MD, CCFP, MSEd Program Head Integrated Psychosocial, Supportive, Palliative Care Program Odette Cancer Centre Sunnybrook Health Sciences Centre Assistant Professor & Associate Head Division of Palliative Care, Dept of Family/Community Medicine University of Toronto *This lecture is supported by an unrestricted educational grant from Roche Canada

2 Breathlessness Objectives Review current understanding of the underlying mechanisms that contribute to the sensation of breathlessness Overview of the evidence re: assessment and management of breathlessness for the oncology population Suggest severity based clinical algorithms

3 Breathlessness Definition Most widely cited description is from the American Thoracic Society consensus statement outlining breathlessness as: a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity. The experience derives from interaction among multiple physiologic, psychological, social, and environmental factors, and may induce secondary physiologic and behavioral responses

4 Breathlessness Prevalence Varies and is dependent on the primary tumor site as well as choice of both assessment tool and the words or phrases used by investigator 46% - advanced lung cancer 7% - advanced gastric cancer Most common reason for an emergency room visit by all patients with cancer

5 Susan 54-year-old, routine outpatient follow up Small cell lung carcinoma Dx 3 months previously Concurrent chemotherapy and radiation 30 pack-year history of cigarette smoking, pulmonary function tests indicate: mild airflow obstruction slight hyperinflation on lung volumes mildly decreased diffusion capacity

6 Susan Pt rates shortness of breath 7/10 on ESAS Does not appear to be in distress Brief nursing assessment clarifies worsening exertional breathlessness of 3 to 4 weeks duration

7 Chuck 57 year old male, small cell carcinoma lung, poor response to two cycles of dexamethasone, cisplatin, VP-16 Presents to ER with 4 days of progressively worsening breathlessness O/E ++distress and accessory muscle use, RR 36/minute, entire right thorax dull to percussion, decreased tactile fremitus on right side

8 Chuck CXR pleural effusion Patient admitted, thoracentesis successful for 450cc fluid, breathlessness improved somewhat subjectively Chest tube inserted Pleurodesis indicated and successfully completed Effusion improved radiologically however breathlessness persisted unchanged How do we treat his breathlessness?

9 Breathlessness Pathophysiology Neural pathways influencing the perception of breathlessness are not fully understood Figure 1 outlines the current understanding of the contributing pathophysiologic mechanisms

10 Figure 1. Pathophysiology of Breathlessness Motor Control Voluntary, Involuntary Motor neurons Chest Wall Diaphragm Phrenic nerve in spinal cord Dudgeon, 2009

11 Breathlessness Pathophysiology Sensory Input a combination of central neural, chemical, mechanical and emotional afferent impulses influence both: Brainstem respiratory network (medulla and pons) Higher brain centers located in the somatosensory and association cortices

12 Breathlessness Pathophysiology Four main categories of sensory input: 1. Biochemical: both central and peripheral chemoreceptors input via vagus nerve detect changes in ph, pco2 and po2 2. Vascular: baroreceptors in the carotid and aortic bodies input via vagus nerve stretch sensitive mechanoreceptors

13 Breathlessness Pathophysiology Four main categories of sensory input: 3. Mechanical receptors: Nasopharynx - input via trigeminal nerve Airway - receptors within epithelium from trachea to bronchioles (lung irritants) and lower airways input via the vagus nerve Lung parenchyma pulmonary C-fibres within alveolar wall (pulmonary congestion, embolism, infection, chemicals) input via vagus nerve Muscles: Intercostal muscles and diaphragm input via spinal and supraspinal reflexes 4. Psychogenic: Affective state (i.e. anxiety and distress) can elicit changes in ventilation and sensation

14 Breathlessness Pathophysiology Motor Output control of respiratory motor activity resides in the brainstem (medulla and pons) Efferent impulses from here produce voluntary and involuntary contraction of the muscles in both the chest wall and the diaphragm

15 Breathlessness Pathophysiology Summary Respiratory motor drive is integrated with sensory input from several sites that, in connection with cognitive input, mediate the perception of breathlessness

16 Breathlessness Etiology Direct (Tumor Related) Parenchymal Lymphangitic carcinomatosis Obstruction Pleural effusion / tumor Pericardial effusion Superior vena cava obstruction Ascites, hepatomegaly Tumor microemboli

17 Breathlessness Etiology Indirect (Cancer Related) Cachexia Mineral & electrolyte imbalances Infections Anemia Pulmonary embolism Pneumothorax Neurologic paraneoplastic syndromes Aspiration

18 Breathlessness Etiology Surgery Treatment Related Radiation pneumonitis / fibrosis Chemotherapy-induced pulm. fibrosis (bleomycin) Chemotherapy-induced cardiomyopathy (adriamycin, cyclophosphamide) Neutropenic infection

19 Breathlessness Acuity Acute (within minutes): Pulmonary embolism Pneumothorax Aspiration Anxiety Subacute (within hours to days): Pneumonia Pleural effusion (can also be chronic) Pericardial effusion Superior vena cava obstruction Anemia Radiation-induced pneumonitis (can also be chronic) Progressive metastatic disease (can also be chronic) Chronic (within days to weeks): Radiation-induced pneumonitis/fibrosis Chemotherapy-induced (pulmonary fibrosis, cardiomyopathy)

20 Breathlessness Assessment May be described by patient as: shortness of breath a smothering feeling inability to get enough air suffocation Respiratory rate, po 2, blood gas determinations DO NOT correlate with the sensation of breathlessness Clinical Pearl it is the patient s opinion of the severity of the symptoms that is the gold standard for symptom assessment

21 Breathlessness Assessment Key Questions: Acuity? (onset and course) Severity? use a visual analog scale (VAS) Pattern? Triggering factors? Effect on activities of daily living?

22 Breathlessness Assessment Key Questions: Mood/psychological state? (mental status, current or history of anxiety, current or history of depression) Meaning? (Is patient fearful of dying?) Current/previous medications? Underlying/concurrent diagnosis? Associated symptoms: cough, fever/chills, sweats, chest pain, wheeze, chest tightness, hemoptysis, hoarseness, edema, weight loss/gain

23 Breathlessness Assessment In the setting of advanced disease, physical exam should be focused and guided by history and underlying illness Clinical Pearl tachypnea does not equate with breathlessness

24 Breathlessness Assessment Appropriateness of an investigation (labs and/or imaging) will depend on the stage of disease and the goals of care for the patient Burden of procedure(s) must be weighed against risk Investigations may contribute meaningful information in the assessment however the results may not affect treatment

25 Breathlessness Assessment Many clinicians make the mistake of equating breathlessness with hypoxemia Very poor correlation has been reported between patient reports of breathlessness and abnormalities in pulmonary function Patients may not show signs of hypoxia but report high levels of breathlessness

26 Susan At rest rates breathing 1-2/10 which increases to 7/10 with one flight of stairs Returns to baseline after 30 minutes No anxiety and no associated symptoms Remainder of symptom screen was negative

27 Susan Repeat chest x-ray: small bilateral pleural effusions mediastinum and hilar adenopathy multiple pulmonary nodules no evidence of changes consistent with COPD no change from previous exam

28 Chuck CXR pleural effusion Patient admitted, thoracentesis successful for 450cc fluid, breathlessness improved somewhat subjectively Chest tube inserted Pleurodesis indicated and successfully completed Effusion improved radiologically however breathlessness persisted unchanged How do we treat his breathlessness?

29 Management of Dyspnea - Anxiolytics Safe in combination with opioids lorazepam mg po q 1 h prn until settled then dose routinely q 4 6 h to keep settled Phenothizines (chlorpromazine, promethazine) may also relieve breathlessness without causing respiratory depression

30 Breathlessness Management Mainstay of management is to: If possible, identify a potentially reversible underlying cause Begin an appropriate and targeted treatment or intervention Evaluate the effectiveness of the treatment or intervention Ensure the symptom of breathlessness is well managed throughout

31 Breathlessness Management Ensure access to fresh air or fan directing air on the face Open door, windows, curtains Encourage rest as needed When laying elevate head of bed When sitting use reclining chair and footrest When moving use assistive devices (walker, wheelchair)

32 Breathlessness Management Non-Pharmacological Interventions: Neuro-electrical muscle stimulation and chest wall vibration = high strength of evidence in their benefit in relieving breathlessness Use of walking aids and breathing training = moderate strength Acupuncture and acupressure = low evidence

33 Breathlessness Management Opioids: Strong evidence from multiple studies and meta-analyses confirm the usefulness of oral and/or parenteral opioids to provide significant clinical benefit in the setting of acute, subacute and chronic breathlessness Incident breathlessness is relieved rapidly with the use of breakthrough opioids Nebulized opioids have not shown to be of any greater benefit than systemic opioids

34 Breathlessness Management Opioids: Respiratory depression is a commonly feared side effect of opioids Although some studies show a decrease in respiratory rate, with the use of opioids, this was not clinically significant as neither hypercapnia nor hypoxygenation resulted

35 Breathlessness Management Non-opioid medications: Oral promethazine may be used as a secondline agent if systemic opioids cannot be used or in addition to systemic opioids Evidence does not support the use of benzodiazepines in the direct management Given the psychogenic role aggressively managing co-morbid psychiatric conditions (anxiety and/or depression) warrants consideration

36 Breathlessness Management Non-opioid medications: Anecdotal reports suggest a role for the use of corticosteroids when targeting specific cancer-related conditions: Obstruction (SVCO and/or airway) Lymphangitic carcinomatosis Radiation pneumonitis

37 Breathlessness Management Non-opioid medications: In the appropriate setting: Antibiotics Anticoagulants Bronchodilators Nebulized saline

38 Breathlessness Management Oxygen: In the setting of patients with advanced cancer, a consistent beneficial effect of oxygen has not been demonstrated Limited by small volume of studies, small numbers of participants and methods used

39 Breathlessness Management Mild (VAS/ESAS 1-3) Clinical Features: Usually can sit/lie quietly Intermittent or persistent Increase with exertion No or mild anxiety Patient does not appear uncomfortable

40 Breathlessness Management Mild (VAS/ESAS 1-3) Consider oxygen (if hypoxemic or deemed helpful by patient) If opioid naïve, consider low dose routine or prn opioid (morphine mg or hydromorphone mg) If on opioids, increase by 25% Ensure breakthrough avail q2h Titrate short acting opioid by 25% every 3 to 5 hours until relief

41 Breathlessness Management Moderate (VAS/ESAS 4-6) Clinical Features: Usually persistent May be new or chronic Settles partially with rest Patient pauses while talking every 30 seconds Breathing appears mildly labored

42 Breathlessness Management Moderate (VAS/ESAS 4-6) Start oxygen (if hypoxemic or deemed helpful by patient) If opioid naïve, consider low dose routine or prn opioid (morphine mg or hydromorphone mg) If on opioids, increase by 25% Ensure breakthrough avail q1h prn Titrate opioid dose by 25% every 2-3 doses until relief

43 Breathlessness Management Severe (VAS/ESAS 7-10) Clinical Features: Often acute on chronic Has worsened over days to weeks Anxiety present Patient pauses while talking every 5 15 seconds Patient appears uncomfortable

44 Breathlessness Management Severe (VAS/ESAS 7-10) Start oxygen (up to 6L/min by NP or higher with mask) Use only short acting opioids to titrate If opioid naïve, begin either morphine PO 5-10mg q4h and 5mg q1h prn or hydromorphone 1-2mg q4h and 1mg q1h prn Titrate opioid dose by 25% every 1-2 doses until relief Consider adjuvant (midazolam, promethazine)

45 Susan At rest rates breathing 1-2/10 which increases to 7/10 with one flight of stairs Returns to baseline after 30 minutes No anxiety and no associated symptoms Remainder of symptom screen was negative

46 Susan Incident breathlessness Offer opioid for breakthrough use Hydromorphone 0.5mg po q2h prn

47 Chuck CXR pleural effusion Patient admitted, thoracentesis successful for 450cc fluid, breathlessness improved somewhat subjectively Chest tube inserted Pleurodesis indicated and successfully completed Effusion improved radiologically however breathlessness persisted unchanged How do we treat his breathlessness?

48 Chuck Rating breathing 9/10 at rest Begin Hydromorphone 0.5mg sc q4h routine Ensure Hydromorphone 0.5mg sc q1h prn Titrate based on response Begin bowel routine

49 Breathlessness A common and distressing symptom for patients with cancer Overall poorly screened for, assessed and managed Assessment and management plans should be targeted to the individual patient Reversible conditions contributing to breathlessness should be addressed Symptom should be well managed using patient self-report in determining efficacy