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Pulmonary management of the neuromuscular patient Tim Short, MBA, BS, RRT. This program has been approved for 1 hour of continuing education credit. Objectives. Discuss management of patients with Amyotrophic Lateral Sclerosis (ALS) Secretion removal Noninvasive ventilation
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Pulmonary managementof the neuromuscular patientTim Short, MBA, BS, RRT This program has been approved for 1 hour of continuing education credit.
Objectives Discuss management of patients with Amyotrophic Lateral Sclerosis (ALS) Secretion removal Noninvasive ventilation American Academy of Neurology (AAN) practice parameters Review the mechanics of airway clearance Identify conditions that benefit from secretion mobilization and/or secretion removal Intrinsic disease Neuromuscular disease Discuss techniques that may be used for airway clearance
Neuromuscular disease Mucociliary transport is often normal Amyotrophic Lateral Sclerosis (ALS) is a progressive neuromuscular disease that affects nerve cells in the brain and the spinal cord Patients with neuromuscular disease have an impaired ability to eliminate secretions It may be due to Lack of respiratory muscle strength Impaired ability to cough ALS is often referred to as "Lou Gehrig's Disease"
50 percent die within three years of disease onset 80 percent die within five years of diagnosis 10 percent live more than 10 years NIV has prolonged the length of survival by treating the respiratory insufficiency. ALS occurs in all races 1.5 to 1.0 ratio of men to women ALS statistics
ALSLung disease When ALS affects the neurons that control the respiratory muscles, breathing becomes strained or weak Begins with shortness of breath during exercise or at night 15 percent never have a breathing problem In the past, diminished breathing was the usual cause of death. Now, there are options. Living with ALS: Adapting to Breathing Changes, 1997, ALS Assoc.
Patient care strategy Offer a comprehensive approach to the management of the ALS patient in the home. Utilize a bi-level S/T ventilatory support system Utilize compliance reporting systems and the device report Provide additional therapies as needed This allows for identification of patients early in the disease process, and for the provision of appropriate therapies for patient management throughout the course of the disease
Lung disease Mucociliary transport is often compromised Increased sputum production is a result of intrinsic lung disease Patient has intact muscle strength for strong coughing
Groups at risk for retaining secretions Intrinsic lung disease Cystic Fibrosis (CF), COPD, bronchiectasis Neuromuscular disease ALS, muscular dystrophy, post polio, multiple sclerosis, spinal muscular atrophy Spinal cord injury, stroke
Airway clearance cycle Inhaled irritant Lung damage Inflammatory response Ineffective airway clearance Obstruction Retained secretions • Mucus production • Biochemical changes
Approximately 90% of episodes of respiratory failure within patients with neuromuscular disease occur during otherwise benign upper respiratory infections because of the inability to clear the airways. Tzeng AC. Bach JR. Prevention of pulmonary Morbidity for Patients with Neuromuscular Disease. Chest. November 2000:Vol. 118, No. 5; 1390-6 Impact of ineffective cough
AAN practice parameters The Care of the Patient with Amyotrophic Lateral Sclerosis (an evidence-based review) American Academy of Neurology (1999) Respiratory Work Group Deborah Gelinas, MD Edward A Oppenheimer, MD
AAN practice parameters Five areas of investigation Breaking the news Symptomatic treatment Nutrition Respiratory insufficiency and mechanical ventilation Advance directives and palliative care
AAN practice parameters Principles of ALS management High priority should be placed on patient autonomy Information is appropriately timed for decision-making Address the full continuum of care Advance directive discussions should be introduced and re-evaluated by the physician
AAN practice parameters Pulmonary measurements Erect sitting vital capacity Supine vital capacity A decrease in VC to 50 percent is associated with respiratory symptoms Nocturnal oximetry Polysomnogram
Measuring cough strength Maximum expiratory pressure Isolates cough muscle strength MEP of 60 cm H2O and higher has been shown to correlate well with the ability to generate adequate cough flows Peak cough flow Simple testing format Peak flow meter and mask Measure Peak Cough Flow (PCF) Normal: 6-12 l/s or 360–720 l/min
Ineffective cough Respiratory muscle strength can deteriorate during respiratory infections PCF between 160 l/minute but less than 270l/min are alsoat risk For this reason, a PCF of 270 l/min has been used to identify patients who would benefit from assisted cough techniques Bach J, Ishikawa Y, et al. Prevention of pulmonary morbidity for patients with Duchenne muscular dystrophy. Chest 1997;112 (4):1024-28
Ineffective cough PCF < 160 l/min Increases risk of respiratory infection Introduces risk of chronic lung damage as a result of recurring lung infection Increases risk of pneumonia and resulting hospitalizations
Airway clearance therapies What to use?
Understanding airway clearance methods Secretion removal Techniques that mobilize and remove secretions from the lungs Secretion mobilization Techniques designed to loosen and mobilize secretions from the lower airway to the upper airway
Secretion clearing/removal techniques Suctioning Manually assisted cough (MAC) Mechanical insufflation-exsufflation (MI-E)
Secretion mobilization techniques Manual chest physiotherapy and postural drainage External percussion and vibration devices High frequency chest wall oscillation (HFCWO) Aerosol therapy Positive expiratory pressure devices (PEP) Intrapulmonary percussive ventilation (IPV) Effective cough needed to clear mobilized secretions
Secretion mobilization techniques “...are effective in mobilizing retained mucous secretions for patients with sick lungs (intrinsic), such as CF and COPD, although these devices will not help a patient whose main problem is impaired cough clearance.” Finder, JD. Review of Airway Clearance Technologies 2006. RT Magazine July 2006 22-25.
Mechanical insufflation-exsufflation (MI-E) Assists patients to clear retained secretions noninvasively Applies a positive pressure to the airway (insufflation) followed by a rapid shift to a negative pressure (exsufflation) simulating a cough May be applied by mask or mouthpiece or invasively via endotracheal or tracheostomy tube
Indications for use for Cough Assist Any patient unable to cough or clear secretions effectively due to reduced peak cough expiratory flow < 270 l/min Contraindications History of bullous emphysema Known susceptibility to pneumothorax or pneumo-mediastinum Recent barotrauma
Benefits of insufflation Neuromuscular disease - reduced VC and Vt and an inability to sigh that result in developing atelectasis and pneumonia1 Provides normal hyperinflation - has been shown to combat loss of chest wall compliance and microatelectasis2 1 Estenne M. et al. Lung volume restriction in patients with chronic respiratory muscle weakness: the role of microatelectasis. Thorax 1993:48(7):698-701 2 Estenne M. et al. Chest wall stiffness in patients with chronic respiratory muscle weakness. Am Rev Respir Dis 1983;128(6):1002-1007
Benefits of exsufflation Flow simulates a natural expiratory cough flow (6-10 l/sec) More effective than invasive suctioning since suctioning has been shown to miss the left mainstem bronchus 90% of the time1 Potentially eliminates the need for invasive suctioning 1 Bach Jr. Room For Imagination:Inspiratory and expiratory muscle aids. Advance. April 2006: 58-60
Inhale + Exhale + Pause = Cycle MI-E treatment Repeat cycle 4-6 times Rest 20-30 seconds Repeat sequence 4-6 times
Typical MI-E settings Pressures (positive and negative) Start low, 10 to 15 cm H2O Get patient acclimated to device Increase pressures as tolerated, 35 to 45 cm H2O ideally1 Times (inhale, exhale and pause) Small children: 1 to 2 sec Adults: 2 to 3 sec 1 Gomez-Marino E et al.Mechanical insufflation-exsufflation. Pressure,volume, and flow relationships and the adequacy of the manufacturer’s guidelines. Am J Phys Rehabil 2002;81(8):579-583.
Settings The goal of inspiratory pressure is to give the patient a good hyper-expansion The goal of expiratory pressure is to replace a good expiratory cough flow Pressures and times vary with each patient
Settings Important to work with patient to find settings which are both comfortable and effective Studies have shown that therapeutic PCF may not be reached with MI-E expiratory pressures less than -40 cm H2O
Clinical benefits Mean peak cough expiratory flow rates of 21 patients with NMD studied Unassisted 1.81 ± 1.03 L/sec Assisted cough 4.27 ± 1.29 L/sec MI-E & MAC 7.47 ± 1.02 L/sec (Normal PCF is 6-12 L/sec) Conclusion: In-exsufflator cough machine improved peak cough expiratory flow rates Bach J. Chest 1993; 104:1553.
Therapy combination benefits MI-E & MAC produced the most effective cough flows Bach et al: Chest, 1993; 104:1553-62.
ALSLung disease during sleep Weakened bulbar muscles can cause closing of the airway Nerve and muscle functions relax during sleep causing under- ventilation With complaints of morning headaches, lethargy, and SOB Early recognition of weakening muscles during REM sleep by: PSG Overnightoximetry Living with ALS: Adapting to Breathing Changes, 1997, ALS Assoc.
AAN practice parameters Early indications of respiratory insufficiency Dyspnea on exertion Supine dyspnea Fatigue Disturbed sleep Morning headaches Noninvasive ventilation should be initiated with the onset of symptoms
AAN practice parameters NIV benefits to the patient Improves the symptoms of hypoventilation Improves quality of life Increases survival by treating the respiratory insufficiency Allows for decision making on more advanced care
AAN practice parameters Recommendations Be vigilant for hypoventilation symptoms Offer noninvasive ventilatory support Offer invasive ventilatory support Respect the right of the patient to refuse therapy When withdrawing ventilation, relieve dyspnea and anxiety
The committee strongly supports the use of mechanical insufflation-exsufflation in patients with DMD Patients with DMD should be taught strategies to improve airway clearance and how to employ those techniques early and aggressively Use assisted cough technologies in patients whose clinical history suggests difficulty in airway clearance, or whose peak cough flow is < 270 l/min and/or whose maximal expiratory pressures are < 60 cm H2O
Quality of life Study aim Initiation of NIV earlier than current “standard of care” may provide additional benefits in terms of respiratory function and quality of life. Jackson et al. A Prospective Evaluation of Pulmonary Function Studies and Symptoms of Hypoventilation in ALS/MND Patients. J Neurol Sci 2002;1610
Quality of life 13 patients 7 received early NIV intervention, 6 received NIV per existing standard of care FVC was done in sitting or supine position Pulse oximetry was performed
Quality of life Conclusions To detect respiratory insufficiency, O2 saturation of less than 90 percent is a more sensitive indicator than FVC of 70 percent Early intervention with NIV increased “vitality” subscale of the SF-36 NIV earlier than current practice may result in improved QOL
BiPAP in OSA with other co morbidities – AVAPS Neuro- Muscular Disorders OSA • AVAPS is the treatment of choice for patients presenting with chronic respiratory disease as well as a mixed SDB pathology. • AVAPS automatic ventilation modality allows normalizing ventilation with a target exhale Vt whereas the EPAP level maintains the UA open (treating OA). • The settable backup rate and the rise time allows better control and adaptation to different types of patients. AVAPS COPD – Overlap Obesity Hypo-Ventilation AVAPS AVAPS
AVAPS Algorithm AVAPS is a ventilation device for patients with respiratory insufficiency ST-T-CP modes can treat central apneas AVAPS: Pressure Support adjustment looking at average tidal volume PS increase or decrease maximum speed is 1 cm H2O/minute AVAPS allow maintaining a target tidal volume +1 cmH2O/min Max -1 cmH2O/min Max BiPAP Synchrony AVAPS 10 PM 7 AM IPAP Max. IPAP Min. EPAP Target Vt
Patient tracing over time Automatically adjusts IPAP to guarantee a target tidal volume
S/T compared to S/T + AVAPS • Pressure support is progressively decreasing: • AVAPS follows patient’s needs and disease progression • The patient is getting better
Clinical benefits of AVAPS Guarantee of ventilatory support during progressive ventilatory changes of the patient Guarantee of ventilatory support during positional changes during sleep Provides the assurance of a tidal volume within a bilevel system Alarms to indicate that tidal volume is not being maintained
Summary Secretion mobilization techniques assist the mucociliary escalator, but they do not assist cough Cough is the principle mechanism for clearing the airways Patients who have an impaired cough mechanism require secretions to be removed Initiation of NIV may improve quality of life and symptoms of hypoventilation in patients with neuromuscular disease