Respiratory Management Following Spinal Cord Injury A William Sheel, PhD W Darlene Reid, PhD, PT Andrea Townson, MD, FRCPC Najib Ayas, MD, MPH, FRCPC www.scireproject.com Version 5.0 Key Points For exercise training to improve respiratory function the training intensity must be relatively high (70- 80% of maximum heart rate) performed three times per week for six weeks. Ideal training regimes have not been identified. Respiratory muscle training improves respiratory muscle strength and endurance in people with SCI. The use of bronchodilators should be considered in subjects with tetraplegia who demonstrate an element of obstructive airway impairment. The effects of other medications commonly used in the management of SCI such as baclofen and oxybutynin should be considered when reviewing airway hyperreactivity in subjects with tetraplegia. The short-term use of oxandrolone can be considered to improve pulmonary function in subjects with tetraplegia. Progressive ventilator free breathing protocol should be considered for ventilator dependent subjects with tetraplegia who are appropriate for ventilator weaning. Resistive and endurance training should be considered in subjects who are candidates for ventilator weaning. Case by case consideration should be given to tracheostomy decannulation in subjects with SCI. The indications and criteria for tracheostomy decannulation have not been established in SCI. Abdominal binding can be used to achieve immediate improvements in respiratory function, but long-term effects can be sustained during its application. Chest wall vibration may improve pulmonary function while the vibration is applied, but carry-over effects when the vibration is not in use has not been evaluated. There is limited evidence that immersion to shoulder-deep 33-34° C water can improve pulmonary function immediately, but carry-over effects following immersion have not been evaluated. Patients with SCI have a high prevalence of obstructive sleep apnea, and therapy may improve quality of life and other outcomes. Therefore, we recommend vigilance for suggestive signs and symptoms (e.g., snoring, obesity, witnessed apneas, daytime sleepiness) and further testing in patients with suggestive symptoms/signs (with overnight oximetry or polysomnography). There is limited evidence that suggests that improving inspiratory and expiratory muscle force is important to maximize expiratory flow during cough. Cough effectiveness can be enhanced by a variety of methods including manual assistance by a caregiver, respiratory muscle training, and/or electrical stimulation triggered by the person with SCI. Cough effectiveness can be enhanced by a variety of methods including manual assistance by a caregiver, respiratory muscle training, and/or electrical stimulation triggered by the person with SCI. Hand-held expiratory pressure devices may enhance secretion removal in people with SCI. There is some evidence that suggests a higher survival rate, as well as better power wheelchair management, phonation success, and patient satisfaction in phrenic paced subjects compared to mechanically ventilated subjects. Phrenic nerve or diaphragmatic stimulation may be used as a long-term alternative to mechanical ventilation for subjects with injuries at C2 or above. Table of Contents Abbreviations ...................................................................................................................................... i 1.0 Introduction .................................................................................................................................. 1 2.0 Systematic Reviews ..................................................................................................................... 3 3.0 Exercise Training of the Upper and Lower Limbs ..................................................................... 6 4.0 Inspiratory Muscle Training ...................................................................................................... 10 5.0 Pharmaceutical Interventions ................................................................................................... 16 5.1 Airway Hyperresponsiveness and Bronchodilators ....................................................................... 16 5.2 Anabolic Agents ........................................................................................................................... 20 5.3 Other Pharmaceuticals ................................................................................................................. 21 6.0 Assistive Devices ....................................................................................................................... 22 6.1 Mechanical Ventilation and Weaning Protocols ............................................................................ 22 6.2 Other Methods of Ventilation ........................................................................................................ 25 6.3 Tracheostomy Placement and Decannulation .............................................................................. 25 6.4 Intermittent Positive Pressure Breathing (IPPB) ........................................................................... 28 6.5 Girdle/Abdominal Binder .............................................................................................................. 29 6.6 Vibration ....................................................................................................................................... 31 6.7 Immersion .................................................................................................................................... 32 7.0 Obstructive Sleep Apnea in SCI ................................................................................................ 33 7.1 Prevalence and Risk Factors ....................................................................................................... 33 8.0 Secretion Removal ..................................................................................................................... 35 9.0 Electrical Stimulation ................................................................................................................. 38 9.1 Phrenic Nerve and Diaphragmatic Stimulation ............................................................................. 38 9.2 Abdominal Neuromuscular Electrical Stimulation ......................................................................... 43 10.0 Summary .................................................................................................................................. 45 11.0 References................................................................................................................................ 50 This review has been prepared based on the scientific and professional information available in 2013. The SCIRE information (print, CD or web site www.scireproject.com) is provided for informational and educational purposes only. If you have or suspect you have a health problem, you should consult your health care provider. The SCIRE editors, contributors and supporting partners shall not be liable for any damages, claims, liabilities, costs or obligations arising from the use or misuse of this material. Sheel AW, Reid WD, Townson AF, Ayas N (2014). Respiratory Management Following Spinal Cord Injury. In: Eng JJ, Teasell RW, Miller WC, Wolfe DL, Townson AF, Hsieh JTC, Connolly SJ, Noonan VK, Loh E, McIntyre A, editors. Spinal Cord Injury Rehabilitation Evidence. Version 5.0. Vancouver: p. 1-55. www.scireproject.com Abbreviations AB Abdominal Binding CNS Central Nervous System COPD Chronic Obstructive Pulmonary Disease CPAP Continuous Positive Airway Pressure DP Diaphragm Pacing ERV Expiratory Reserve Volume ES-LCE Electrical Stimulation induced Leg Cycle Ergometry fb Frequency of Breathing FRC Functional Residual Capacity FES Functional Electrical Stimulation FEV1 Forced Expiratory Volume in One Second FVC Forced Vital Capacity HFPV High Frequency Percussion Ventilation HVtV High Tidal Volume Ventilation IC Inspiratory Capacity IH Isocapnic Hyperpnoea IMT Inspiratory Muscle Training IMV Intermittent Mandatory Ventilation IPPB Intermittent Positive-Pressure Breathing IRV Inspiratory Reserve Volume MDI Metered-Dose Inhaler MEP (or PEmax) Maximal Expiratory Pressure MIE Mechanical Insufflation-Exsufflation MIP (or PImax) Maximal Inspiratory Pressure MV Mechanical Ventilation MVV Maximal Voluntary Ventilation Pes Esophageal Pressure Pga Gastric Pressure PaCO2 Partial Pressure of Arterial Carbon Dioxide PaO2 Partial Pressure of Arterial Oxygen PEFR Peak Expiratory Flow Rate PEmax Maximal Expiratory Pressure PImax Maximal Inspiratory Pressure PNS Phrenic Nerve Stimulation PVFB Progressive Ventilator Free Breathing REP Resistive Endurance Protocol RI Respiratory Infection RMT Respiratory Muscle Training RV Residual Volume SIP Maximal Sustainable Mouth Pressure Tlim Endurance Time Sustained on Training Load TLC Total Lung Capacity TLmax Maximal Incremental Threshold Load Ti/Ttot Inspiratory Time/Total Time for One Breath TV (or VT) Tidal Volume TRAMS Tracheostomy Review And Management Service UNDW Ultrasonically Nebulized Distilled Water VC Vital Capacity VE Minute Ventilation i Respiratory Management Following Spinal Cord Injury 1.0 Introduction The respiratory system, including the lungs, respiratory muscles, and neural control system, is a complex integrated physiological system that is not yet fully understood. The respiratory system is unique in