Incidence and Risk Factors of Pneumonia in Individuals With Acute Spinal Cord Injury: A Multi-national, Multi-center, Prospective Cohort Study

OBJECTIVE

To describe the occurrence of pneumonia in individuals with acute spinal cord injury (SCI) and identify its key predictors.

DESIGN

Multi-centric, longitudinal cohort study.

SETTING

10 specialized SCI rehabilitation units in Europe and Australia.

PARTICIPANTS

Eligible were 902 men and women with acute SCI, aged 18 years or older, with cervical or thoracic lesions and not dependent on 24-hour mechanical ventilation; 503 participated in the study (N=503).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

We assessed demographics and lesion related parameters at study entry, and any pneumonia events throughout inpatient rehabilitation. Respiratory function, decubitus, and urinary tract infections were assessed at 1, 3, and 6 months post injury as well as at discharge from inpatient rehabilitation. Time to event (pneumonia) analyses were done using the Kaplan-Meier method, and potential predictors for pneumonia were analyzed with multivariable survival models.

RESULTS

Five hundred three patients with SCI were included, with 70 experiencing at least 1 pneumonia event. 11 participants experienced 2 or more events during inpatient rehabilitation. Most events occurred very early after injury, with a median of 6 days. Pneumonia risk was associated with tetraplegia (hazard ratio [HR]=1.78; 95% confidence interval [CI] 1.00-3.17) and traumatic etiology (HR=3.75; 95% CI 1.30-10.8) American Spinal Injury Impairment Scale (AIS) A (HR=5.30; 95% CI 2.28-12.31), B (HR=4.38; 95% CI 1.77-10.83), or C (HR=4.09; 95% CI 1.71-9.81) lesions. For every 10 cmH2O increase in inspiratory muscle strength, pneumonia risk was reduced by 13% (HR=0.87; 95% CI 0.78-0.97).

CONCLUSION

Pneumonia is a major complication after SCI with the highest incidence very early after injury. Individuals with traumatic or AIS A, B, or C tetraplegia are at highest risk for pneumonia.

Breathing control training for functional seizures: A multi-site, open-label pilot study

There are no well-validated treatments for functional seizures. While specialist psychotherapy is usually recommended, the evidence for its benefit is qualified, and it can be difficult to obtain. Given the association between hyperventilation and functional seizures we explored an alternative modality, breathing control training, in a multi-site open label pilot trial. Participants with functional seizures over the age of 16 received an hour of breathing training from a respiratory physiotherapist, with a half-hour booster session a month later. Seizure frequency and Nijmegen scores (a measure of hyperventilation) were reported at baseline and follow-up, 3-4 months later. Eighteen subjects were recruited, and 10 completed follow-up. Seven of these 10 had improved seizure frequency, and 3 did not (Wilcoxon signed rank test, p = 0.09), with seizure frequency correlating with Nijmegen score (Spearman's rank correlation = 0.75, p = 0.034). The intervention was well tolerated, with no adverse events reported. These preliminary results support a potentially new approach to treating functional seizures that should prove cost-effective and acceptable, though require confirmation by a randomised controlled trial.

Management of Sleep-Disordered Breathing in a Spinal Cord Injury Rehabilitation Center: Model of Care Adaptation and Implementation

Background

Obstructive sleep apnea (OSA) is highly prevalent and poorly managed in spinal cord injury (SCI). Alternative management models are urgently needed to improve access to care. We previously described the unique models of three SCI rehabilitation centers that independently manage uncomplicated OSA.

Objectives

The primary objective was to adapt and implement a similar rehabilitation-led model of managing OSA in an SCI rehabilitation center in Australia. Secondary objectives were to identify the local barriers to implementation and develop and deliver tailored interventions to address them.

Methods

A clinical advisory group comprised of rehabilitation clinicians, external respiratory clinicians, and researchers adapted and developed the care model. A theory-informed needs analysis was performed to identify local barriers to implementation. Tailored behavior change interventions were developed to address the barriers and prepare the center for implementation.

Results

Pathways for ambulatory assessments and treatments were developed, which included referral for specialist respiratory management of complicated cases. Roles were allocated to the team of rehabilitation doctors, physiotherapists, and nurses. The team initially lacked sufficient knowledge, skills, and confidence to deliver the OSA care model. To address this, comprehensive education and training were provided. Diagnostic and treatment equipment were acquired. The OSA care model was implemented in July 2022.

Conclusion

This is the first time a rehabilitation-led model of managing OSA has been implemented in an SCI rehabilitation center in Australia. We describe a theory-informed method of adapting the model of care, assessing the barriers, and delivering interventions to overcome them. Results of the mixed-methods evaluation will be reported separately.

Understanding the Relationships Between Sleep Quality and Depression and Anxiety in Neurotrauma: A Scoping Review

Sleep problems, depression, and anxiety are highly prevalent after a spinal cord injury (SCI) and traumatic brain injury (TBI) and may worsen functional outcomes and quality of life. This scoping review examined the existing literature to understand the relationships between sleep quality, depression, and anxiety in persons with SCI and TBI, and to identify gaps in the literature. A systematic search of seven databases was conducted. The findings of 30 eligible studies reporting associations between sleep quality and depression and/or anxiety after SCI or TBI were synthesized. The included studies were mostly cross-sectional and employed a range of subjective and objective measures of sleep quality. Poor subjective sleep quality and insomnia tended to be significantly associated with increased levels of depression and/or anxiety, but no such associations were reported when sleep quality was measured objectively. Two longitudinal studies observed worsening depressive symptoms over time were related to insomnia and persistent sleep complaints. Two interventional studies found that treating sleep problems improved symptoms of depression and anxiety. The findings of this review suggest that sleep and psychopathology are related in persons with neurotraumatic injuries. This has important therapeutic implications, because individuals may benefit from therapy targeting both sleep and psychological issues. More longitudinal and interventional studies are warranted to further understand the direction and strength of the relationships and how they impact patient outcomes.

Prevalence of central sleep apnea in people with tetraplegic spinal cord injury: a retrospective analysis of research and clinical data

STUDY OBJECTIVES

Over 80% of people with tetraplegia have sleep-disordered breathing (SDB), but whether this is predominantly obstructive or central is unclear. This study aimed to estimate the prevalence of central sleep apnea (CSA) in tetraplegia and the contributions of central, obstructive, and hypopnea respiratory events to SDB summary indices in tetraplegia.

METHODS

Research and clinical data from 606 individuals with tetraplegia and full overnight polysomnography were collated. The proportions of different respiratory event types were calculated; overall and for mild, moderate, and severe disease. The prevalence of Predominant CSA (Central Apnea Index [CAI] ≥ 5 and more central than obstructive apneas) and Any CSA (CAI ≥ 5) was estimated. Prevalence of sleep-related hypoventilation (SRH) was estimated in a clinical sub-cohort.

RESULTS

Respiratory events were primarily hypopneas (71%), followed by obstructive (23%), central (4%), and mixed apneas (2%). As severity increased, the relative contribution of hypopneas and central apneas decreased, while that of obstructive apneas increased. The prevalence of Predominant CSA and Any CSA were 4.3% (26/606) and 8.4% (51/606) respectively. Being male, on opiates and having a high tetraplegic spinal cord injury were associated with CSA. SRH was identified in 26% (26/113) of the clinical sub-cohort.

CONCLUSIONS

This is the largest study to characterize SDB in tetraplegia. It provides strong evidence that obstructive sleep apnea is the predominant SDB type; 9-18 times more prevalent than CSA. The prevalence of CSA was estimated to be 4%-8%, significantly lower than previously reported.

A Randomized Controlled Clinical Trial of Lung Volume Recruitment in Adults with Neuromuscular Disease

Rationale: Clinical care guidelines advise that lung volume recruitment (LVR) be performed routinely by people with neuromuscular disease (NMD) to maintain lung and chest wall flexibility and slow lung function decline. However, the evidence base is limited, and no randomized controlled trials of regular LVR in adults have been published. Objectives: To evaluate the effect of regular LVR on respiratory function and quality of life in adults with NMD. Methods: A randomized controlled trial with assessor blinding was conducted between September 2015 and May 2019. People (>14 years old) with NMD and vital capacity <80% predicted were eligible, stratified by disease subgroup (amyotrophic lateral sclerosis/motor neuron disease or other NMDs), and randomized to 3 months of twice-daily LVR or breathing exercises. The primary outcome was change in maximum insufflation capacity (MIC) from baseline to 3 months, analyzed using a linear mixed model approach. Results: Seventy-six participants (47% woman; median age, 57 [31-68] years; mean baseline vital capacity, 40 ± 18% predicted) were randomized (LVR, n = 37). Seventy-three participants completed the study. There was a statistically significant difference in MIC between groups (linear model interaction effect P = 0.002, observed mean difference, 0.19 [0.00-0.39] L). MIC increased by 0.13 (0.01-0.25) L in the LVR group, predominantly within the first month. No interaction or treatment effects were observed in secondary outcomes of lung volumes, respiratory system compliance, and quality of life. No adverse events were reported. Conclusions: Regular LVR increased MIC in a sample of LVR-naive participants with NMD. We found no direct evidence that regular LVR modifies respiratory mechanics or slows the rate of lung volume decline. The implications of increasing MIC are unclear, and the change in MIC may represent practice. Prospective long-term clinical cohorts with comprehensive follow-up, objective LVR use, and clinically meaningful outcome data are needed. Clinical trial registered with anzctr.org.au (ACTRN12615000565549).

The complexity of multidisciplinary respiratory care in amyotrophic lateral sclerosis

Motor neurone disease/amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder with no known cure, where death is usually secondary to progressive respiratory failure. Assisting people with ALS through their disease journey is complex and supported by clinics that provide comprehensive multidisciplinary care (MDC). This review aims to apply both a respiratory and a complexity lens to the key roles and areas of practice within the MDC model in ALS. Models of noninvasive ventilation care, and considerations in the provision of palliative therapy, respiratory support, and speech and language therapy are discussed. The impact on people living with ALS of both inequitable funding models and the complexity of clinical care decisions are illustrated using case vignettes. Considerations of the impact of emerging antisense and gene modifying therapies on MDC challenges are also highlighted. The review seeks to illustrate how MDC members contribute to collective decision-making in ALS, how the sum of the parts is greater than any individual care component or health professional, and that the MDC per se adds value to the person living with ALS. Through this approach we hope to support clinicians to navigate the space between what are minimum, guideline-driven, standards of care and what excellent, person-centred ALS care that fully embraces complexity could be.

Educational aims

To highlight the complexities surrounding respiratory care in ALS.To alert clinicians to the risk that complexity of ALS care may modify the effectiveness of any specific, evidence-based therapy for ALS.To describe the importance of person-centred care and shared decision-making in optimising care in ALS.

The role of lung volume recruitment therapy in neuromuscular disease: a narrative review

Respiratory muscle weakness results in substantial discomfort, disability, and ultimately death in many neuromuscular diseases. Respiratory system impairment manifests as shallow breathing, poor cough and associated difficulty clearing mucus, respiratory tract infections, hypoventilation, sleep-disordered breathing, and chronic ventilatory failure. Ventilatory support (i.e., non-invasive ventilation) is an established and key treatment for the latter. As survival outcomes improve for people living with many neuromuscular diseases, there is a shift towards more proactive and preventative chronic disease multidisciplinary care models that aim to manage symptoms, improve morbidity, and reduce mortality. Clinical care guidelines typically recommend therapies to improve cough effectiveness and mobilise mucus, with the aim of averting acute respiratory compromise or respiratory tract infections. Moreover, preventing recurrent infective episodes may prevent secondary parenchymal pathology and further lung function decline. Regular use of techniques that augment lung volume has similarly been recommended (volume recruitment). It has been speculated that enhancing lung inflation in people with respiratory muscle weakness when well may improve respiratory system "flexibility", mitigate restrictive chest wall disease, and slow lung volume decline. Unfortunately, clinical care guidelines are based largely on clinical rationale and consensus opinion rather than level A evidence. This narrative review outlines the physiological changes that occur in people with neuromuscular disease and how these changes impact on breathing, cough, and respiratory tract infections. The biological rationale for lung volume recruitment is provided, and the clinical trials that examine the immediate, short-term, and longer-term outcomes of lung volume recruitment in paediatric and adult neuromuscular diseases are presented and the results synthesised.

The impact of sleep quality on health, participation and employment outcomes in people with spinal cord injury: Analyses from a large cross-sectional survey

BACKGROUND

Poor sleep is common in people with spinal cord injury (SCI), yet little is known about its impact on employment and participation outcomes.

OBJECTIVES

This study aimed to (1) describe the sleep quality of a large sample of Australians with SCI and compare the results to data from an adult control and other clinical populations; (2) examine associations between sleep quality and participant characteristics; and (3) explore the relationship between sleep and outcomes.

METHODS

Cross-sectional data from the Australian arm of the International Spinal Cord Injury (Aus-InSCI) survey from 1579 community-dwelling people aged >18 years with SCI were analysed. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI). Relationships between participant characteristics, sleep quality and other outcomes were examined with linear and logistic regression.

RESULTS

The PSQI was completed by 1172 individuals; 68% reported poor sleep (global PSQI score >5). Subjective sleep quality in people with SCI was poor (mean PSQI = 8.5, SD 4.5) when compared to adults without SCI (PSQI = 5.00, SD 3.37) and with traumatic brain injury (PSQI = 5.54, SD 3.94). Financial hardship and problems with secondary health conditions were significantly associated with worse sleep quality (p < 0.05). Poor sleep quality was strongly associated with lower emotional wellbeing and energy, and greater problems with participation (p < 0.001). Individuals engaged in paid work reported better sleep quality (mean PSQI = 8.1, SD 4.3) than unemployed individuals (mean PSQI = 8.7, SD 4.6; p < 0.05). Following adjustment for age, pre-injury employment, injury severity and years of education, better sleep quality remained strongly associated with being employed (OR 0.95, 95% CI 0.92 to 0.98; p = 0.003).

CONCLUSIONS

This study demonstrated pervasive and impactful relationships between sleep quality and important SCI outcomes. Poor sleep quality was strongly associated with worse emotional wellbeing and vitality, unemployment and lower participation. Future studies should aim to determine whether treating sleep problems can improve outcomes for people living with SCI.

Barriers and enablers to telehealth use by physiotherapists during the COVID-19 pandemic

OBJECTIVES

To investigate the perceived barriers and enablers experienced by physiotherapists whilst delivering community and outpatient services during the COVID-19 pandemic.

METHODS

Qualitative study undertaken at a University-affiliated hospital in Melbourne, Australia. Physiotherapists working in the outpatient setting participated in a semi-structured interview. Interviews were analysed using Framework Analysis, with themes mapped to the Theoretical Domains Framework (TDF).

RESULTS

From 19 interviews, we identified major themes and mapped these to the TDF domains: 1. The pandemic rapidly closed the knowledge-practice gap; 2. Adaptation of existing skills and integration of new skills were required; 3. Supportive senior leadership helped the transition; 4. Capabilities and confidence improved with time; 5. Environmental factors were crucial to success or failure of telehealth; 6. Access to and delivery of care improved for some; 7. Identification of appropriate patients and future hybrid models of care; 8. Changes in work practices, role certainty and identity; 9. Development of educational resources consolidated knowledge; 10. Socialisation of telehealth and optimism for the future. Within each domain, key barriers and enablers were also identified.

CONCLUSIONS

The findings of this study suggest that the delivery of community and outpatient physiotherapy via telehealth during the COVID-19 pandemic was an initial challenge. Growing knowledge, confidence and ability to problem solve barriers enabled physiotherapists to move along the continuum of 'fear' to 'triumph' as the pandemic progressed. These results can be used by clinicians, managers, and academics to guide future workforce planning, hospital environmental design, and service delivery. CLINICAL MESSAGE.

Respiratory muscle training in neuromuscular disease: a systematic review and meta-analysis

Background

Neuromuscular disease causes a progressive decline in ventilatory function which respiratory muscle training may address. Previous systematic reviews have focussed on single diseases, whereas this study systematically reviewed the collective evidence for respiratory muscle training in children and adults with any neuromuscular disease.

Methods

Seven databases were searched for randomised controlled trials. Three reviewers independently reviewed eligibility, extracted characteristics, results, determined risk of bias and combined results using narrative synthesis and meta-analysis.

Results

37 studies (40 publications from 1986–2021, n=951 participants) were included. Respiratory muscle training improved forced vital capacity (standardised mean difference (SMD) 0.40 (95% confidence interval 0.12–0.69)), maximal inspiratory (SMD 0.53 (0.21–0.85)) and maximal expiratory pressure (SMD 0.70 (0.35–1.04)) compared to control (usual care, sham or alternative treatment). No impact on cough, dyspnoea, voice, physical capacity or quality of life was detected. There was high degree of variability between studies.

Discussion

Study heterogeneity (children and adults, different diseases, interventions, dosage and comparators) suggests that the results should be interpreted with caution. Including all neuromuscular diseases increased the evidence pool and tested the intervention overall.

Conclusions

Respiratory muscle training improves lung volumes and respiratory muscle strength in neuromuscular disease, but confidence is tempered by limitations in the underlying research.

Rapidly and slowly progressive neuromuscular disease: differences in pulmonary function, respiratory tract infections and response to lung volume recruitment therapy (LVR)

INTRODUCTION

Reduced lung volumes are a hallmark of respiratory muscle weakness in neuromuscular disease (NMD). Low respiratory system compliance (C_rs) may contribute to restriction and be amenable to lung volume recruitment (LVR) therapy. This study evaluated respiratory function and the immediate impact of LVR in rapidly progressive compared to slowly progressive NMD.

METHODS

We compared vital capacity (VC), static lung volumes, maximal inspiratory and expiratory pressures (MIP, MEP), C_rs and peak cough flow (PCF) in 80 adult participants with motor neuron disease ('MND'=27) and more slowly progressive NMDs ('other NMD'=53), pre and post a single session of LVR. Relationships between respiratory markers and a history of respiratory tract infections (RTI) were examined.

RESULTS

Participants with other NMD had lower lung volumes and C_rs but similar reduction in respiratory muscle strength compared with participants with MND (VC=1.30±0.77 vs 2.12±0.75 L, p<0.001; C_rs=0.0331±0.0245 vs 0.0473±0.0241 L/cmH₂O, p=0.024; MIP=39.8±21.3 vs 37.8±19.5 cmH₂O). More participants with other NMD reported an RTI in the previous year (53% vs 22%, p=0.01). The likelihood of having a prior RTI was associated with baseline VC (%predicted) (OR=1.03 (95% CI 1.00 to 1.06), p=0.029). Published thresholds (VC<1.1 L or PCF<270 L/min) were, however, not associated with prior RTI.A single session of LVR improved C_rs (mean (95% CI) increase = 0.0038 (0.0001 to 0.0075) L/cmH₂O, p=0.047) but not VC.

CONCLUSION

These findings corroborate the hypothesis that ventilatory restriction in NMD is related to weakness initially with respiratory system stiffness potentiating lung volume loss in slowly progressive disease. A single session of LVR can improve C_rs. A randomised controlled trial of regular LVR is needed to assess longer-term effects.

Efficacy of Repeating Pulmonary Rehabilitation in People with COPD: A Systematic Review

Background

Pulmonary rehabilitation is an effective intervention for people with chronic obstructive pulmonary disease (COPD). People with COPD undertake repeat programs, but synthesis of evidence regarding such practice has not been undertaken. The aim of this systematic review was to establish the effects of repeating pulmonary rehabilitation subsequent to an initial program in people with COPD.

Methods

Studies where participants with COPD undertook >1 pulmonary rehabilitation program were included, incorporating RCT (randomized controlled trial) and non-randomized studies. Electronic database searches were undertaken. Two authors independently undertook study identification, data extraction and risk of bias assessment. The primary outcome was health-related quality of life (HRQoL); secondary outcomes were exercise capacity, hospitalizations and exacerbations, adherence, mortality and adverse events. Narrative synthesis was undertaken for clinically heterogeneous trials. Data from RCTs and non-randomized studies were not combined for analysis.

Results

Ten included studies (2 RCTs) involved 907 participants with COPD (n=653 had undertaken >1 program). The majority of studies were at high risk of bias. One RCT (n=33) reported no difference in HRQol after a repeat program vs usual care following exacerbation (Chronic Respiratory Disease Questionnaire dyspnea domain score MD 0.4, 95% CI -0.5 to 3). In stable patients, clinically important and statistically significant improvements in HRQoL and exercise capacity were reported after repeat programs, but of a smaller magnitude than initial programs. There was evidence for reductions in exacerbations and hospitalizations, and shorter hospital length of stay for patients who repeated a program twice in 12 months compared to those who repeated once. No data for mortality or adverse events were available.

Conclusion

This systematic review provides limited evidence for benefits of repeating pulmonary rehabilitation in people with COPD, including improved HRQoL and exercise capacity, and reduced hospitalizations. However, most studies have high risk of bias, which reduces the certainty of these conclusions.

Study Registration

PROSPERO (CRD42020215093).

Tetraplegic obstructive sleep apnoea patients dilate the airway similarly to able-bodied obstructive sleep apnoea patients

Context/objective: Obstructive sleep apnoea (OSA) develops soon after cervical spinal cord injury (SCI) at rates higher than the general population, but the mechanisms are not understood. This study aimed to determine whether OSA in SCI is associated with altered pharyngeal muscle dilatory mechanics during quiet breathing, as has been observed in the non-SCI injured with obstructive sleep apnoea.Design: Cross sectional imaging study.Setting: Medical research institute.Participants: Eight cervical SCI patients with OSA were recruited and compared to 13 able-bodied OSA patients and 12 able-bodied healthy controls of similar age and BMI.Interventions and outcome measures: 3T MRI scans of upper airway anatomy and tagged-MRI to characterize airway muscle motion during quiet breathing were collected for analysis.Results: Considerable variation in the patterns of inspiratory airway muscle motion was observed in the SCI group, with some participants exhibiting large inspiratory airway dilatory motions, and others exhibiting counterproductive narrowing during inspiration. These patterns were not dissimilar to those observed in the able-bodied OSA participants. The increase in airway cross-sectional area of able-bodied control participants was proportional to increase in BMI, and a similar, but not significant, relationship was present in all groups.Conclusion: Despite the limited sample size, these data suggest that SCI OSA patients have heterogeneous pharyngeal dilator muscle responses to the negative pressures occurring during inspiration but, as a group, appear to be more similar to able-bodied OSA patients than healthy controls of similar age and BMI. This may reflect altered pharyngeal pressure reflex responses in at least some people with SCI.

Management of sleep-disordered breathing in three spinal cord injury rehabilitation centres around the world: a mixed-methods study

STUDY DESIGN

Mixed-methods observational study.

OBJECTIVE

To describe the sleep-disordered breathing (SDB) management models of three spinal cord injury (SCI) rehabilitation centres that are screening, diagnosing and treating uncomplicated SDB, and to determine their common elements.

SETTING

Three specialist SCI rehabilitation centres.

METHODS

Data collection at each site included direct observations and interviews with lead clinical staff and an audit of SDB-related clinical practice in 2019. Detailed descriptions of the models of care, including process maps, were developed. A theory-based analysis of the common elements of the three care models was undertaken.

RESULTS

At each centre a multidisciplinary team, consisting of medical, allied health and/or nursing staff, provided a comprehensive SDB management service that included screening, diagnosis and treatment. Inpatients with SCI were assessed for SDB with overnight oximetry and/or polygraphy. Further assessment of patient symptoms, respiratory function, and hypercapnia supported the diagnostic process. Treatment with positive airway pressure was initiated on the ward. Having a collaborative, skilled team with strong leadership and adequate resources were the key, common enablers to providing the service.

CONCLUSION

It is feasible for multi-disciplinary SCI rehabilitation teams to independently diagnose and treat uncomplicated SDB without referral to specialist sleep services provided they are adequately resourced with equipment and skilled staff. Similar models of care could substantially improve access to SDB treatment for people with SCI. Further research is required to determine the non-inferiority of these alternatives to specialist care.

Routine lung volume recruitment in boys with Duchenne muscular dystrophy: a randomised clinical trial

BACKGROUND

Impaired cough results in airway secretion retention, atelectasis and pneumonia in individuals with Duchenne muscular dystrophy (DMD). Lung volume recruitment (LVR) stacks breaths to inflate the lungs to greater volumes than spontaneous effort. LVR is recommended in DMD clinical care guidelines but is not well studied. We aimed to determine whether twice-daily LVR, compared with standard of care alone, attenuates the decline in FVC at 2 years in boys with DMD.

METHODS

In this multicentre, assessor-blinded, randomised controlled trial, boys with DMD, aged 6-16 years with FVC >30% predicted, were randomised to receive conventional treatment or conventional treatment plus manual LVR twice daily for 2 years. The primary outcome was FVC % predicted at 2 years, adjusted for baseline FVC % predicted, age and ambulatory status. Secondary outcomes included change in chest wall distensibility (maximal insufflation capacity minus FVC) and peak cough flow.

RESULTS

Sixty-six boys (36 in LVR group, 30 in control) were evaluated (median age (IQR): 11.5 years (9.5-13.5), median baseline FVC (IQR): 85% predicted (73-96)). Adjusted mean difference in FVC between groups at 2 years was 1.9% predicted (95% CI -6.9% to 10.7%; p=0.68) in the direction of treatment benefit. We found no differences in secondary outcomes.

CONCLUSION

There was no difference in decline in FVC % predicted with use of twice-daily LVR for boys with DMD and relatively normal lung function. The burden associated with routine LVR may outweigh the benefit. Benefits of LVR to maintain lung health in boys with worse baseline lung function still need to be clarified.

TRIAL REGISTRATION NUMBER

NCT01999075.

Perceived sleep problems after spinal cord injury: Results from a community-based survey in Switzerland

Objective: To investigate the burden of sleep problems within the Spinal Cord injured (SCI) community with respect to the general population (GP) in Switzerland. The study further explored potential predictors for receiving treatment for sleep problems after SCI.Design: Cross-sectional study.Setting: SCI community in Switzerland.Participants: Individuals diagnosed with an SCI, aged 16 years or older that permanently reside in Switzerland (N = 1549).Interventions: Not applicable.Outcome measures: Perceived sleep problems within the SCI community and GP. For those with sleep problems and SCI, an indicator for having received treatment was measured.Results: 58.8% of survey participants indicated having a sleep problem; 69.4% of those with a sleep problem did not indicate receiving treatment. Amongst people living with an SCI, individuals between the ages of 46-60 years (adjusted Odds Ratio, OR = 3.07; 95% CI 1.54-6.16), participants reporting severe financial hardship (OR = 2.90; 95% CI) 1.69-4.96, and those that indicated having pain (OR = 5.62; 95% CI 3.52-8.98) were more likely to have a chronic sleep problem. In comparison to the Swiss GP, the prevalence of having a sleep problem was 18% higher among persons with SCI, with the largest discrepancy for males with paraplegia between the ages of 46-60 years (Prevalence ratio, PR = 1.28; 95% CI, 1.21-1.36).Conclusion: Individuals with SCI experience more sleep problems compared to the Swiss GP. Findings from this study suggest that clinical screening for sleep issues targeting high risk groups is needed to reduce the large prevalence of non-treatment in individuals with SCI.

Measuring Adherence to Long-Term Noninvasive Ventilation

BACKGROUND

Obtaining benefits from long-term noninvasive ventilation (NIV) relies on achieving adequate adherence to treatment. Reported adherence to NIV is variable and could be influenced by high-volume users and attrition of nonusers and those who die. This observational study aimed to describe patterns of use and adherence rates in new unselected users of NIV.

METHODS

All adults (> 18 y old) commencing long-term NIV were consecutively enrolled and followed for 6 months. Ventilator data were manually downloaded from devices and usage (minutes per day) was collected. Subjects were categorized into adherent users (≥ 4 h/d) and nonadherent users (< 4 h/d).

RESULTS

Data were obtained from 86 subjects. Most (65%) had motor neuron disease, and most commenced NIV in an out-patient setting (72%). At one month after NIV implementation, overall average daily use was 302.1 min/d and categorical adherence was 57%. At 6 months or prior to death, overall average daily use increased (388.7 min/d), but categorical adherence was similar (62%). The majority of subjects (84%) remained in the same adherence category from their first month to their sixth month of use or death. Individuals with motor neuron disease demonstrated significantly lower rates of adherence compared to the rest of the cohort at 1 month (48% vs 73%, P = .03). In those who died within the study period (n = 19, all with motor neuron disease), this difference persisted to death (42% at death vs 73% at 6 months, P = .032).

CONCLUSIONS

Average daily usage may conceal true prevalence of adherence or nonadherence to NIV within a population. Reporting both average daily use data and categorical adherence rates (using a threshold of 4 h/d) may improve transparency of reported outcomes from clinical trials and identifies a therapeutic target for home mechanical ventilation services for quality improvement.

Physical activity of patients with critical illness undergoing rehabilitation in intensive care and on the acute ward: An observational cohort study

BACKGROUND

There are limited published data on physical activity of survivors of critical illness engaged in rehabilitation in hospital, despite it plausibly influencing outcome.

OBJECTIVE

The aims of this study were to measure physical activity of patients with critical illness engaged in rehabilitation in the intensive care unit (ICU) and on the acute ward and report discharge destination, muscle strength, and functional outcomes.

METHODS

This was a single-centre, prospective observational study. Adults with critical illness, who received ≥48 h of invasive mechanical ventilation, and who were awake and able to participate in rehabilitation were eligible. To record physical activity, participants wore BodyMedia SenseWear Armbands (BodyMedia Incorporated, USA), during daylight hours, from enrolment until hospital discharge or day 14 of ward stay (whichever occurred first). The primary outcome was time (minutes) spent performing physical activity at an intensity of greater than 1.5 Metabolic Equivalent Tasks. Secondary outcomes included discharge destination, muscle strength, and physical function.

RESULTS

We collected 807 days of physical activity data (363 days ICU, 424 days ward) from 59 participants. Mean (standard deviation) duration of daily physical activity increased from the ICU, 17.8 (22.8) minutes, to the ward, 52.8 (51.2) minutes (mean difference [95% confidence interval] = 35 [23.8-46.1] minutes, P < .001). High levels of activity in the ICU were associated with higher levels of activity on the ward (r = .728), n = 48, P < .001.

CONCLUSIONS

Patients recovering from critical illness spend less than 5% of the day being physically active throughout hospital admission, even when receiving rehabilitation. Physical activity increased after discharge from intensive care, but had no relationship with discharge destination. Only the absence of ICU-acquired weakness on awakening was associated with discharge directly home from the acute hospital. Future studies could target early identification of ICU-acquired weakness and the preservation of muscle strength to improve discharge outcomes.

Objective measurement of lung volume recruitment therapy: laboratory and clinical validation

Lung volume recruitment manoeuvres are often prescribed to maintain respiratory health in neuromuscular disease. Unfortunately, no current system accurately records delivered dose. This study determined the performance characteristics of a novel, objective, manual lung volume recruitment bag counter (‘the counter’) with bench and healthy volunteer testing, as well as in individuals with neuromuscular disease. We undertook (1) bench test determination of activation threshold, (2) bench and healthy volunteer fidelity testing during simulated patient interface leak and different pressure compressions and (3) comparisons with self-report in individuals with neuromuscular disease. The data are reported as summary statistics, compression counts, percentage of recorded versus delivered compressions and concordance (Cohen’s kappa (K) and absolute agreement).

Implementation of the StandingTall programme to prevent falls in older people: a process evaluation protocol

INTRODUCTION

One in three people aged 65 years and over fall each year. The health, economic and personal impact of falls will grow substantially in the coming years due to population ageing. Developing and implementing cost-effective strategies to prevent falls and mobility problems among older people is therefore an urgent public health challenge. StandingTall is a low-cost, unsupervised, home-based balance exercise programme delivered through a computer or tablet. StandingTall has a simple user-interface that incorporates physical and behavioural elements designed to promote compliance. A large randomised controlled trial in 503 community-dwelling older people has shown that StandingTall is safe, has high adherence rates and is effective in improving balance and reducing falls. The current project targets a major need for older people and will address the final steps needed to scale this innovative technology for widespread use by older people across Australia and internationally.

METHODS AND ANALYSIS

This project will endeavour to recruit 300 participants across three sites in Australia and 100 participants in the UK. The aim of the study is to evaluate the implementation of StandingTall into the community and health service settings in Australia and the UK. The nested process evaluation will use both quantitative and qualitative methods to explore uptake and acceptability of the StandingTall programme and associated resources. The primary outcome is participant adherence to the StandingTall programme over 6 months.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the South East Sydney Local Health District Human Research Ethics Committee (HREC reference 18/288) in Australia and the North West- Greater Manchester South Research Ethics Committee (IRAS ID: 268954) in the UK. Dissemination will be via publications, conferences, newsletter articles, social media, talks to clinicians and consumers and meetings with health departments/managers.

TRIAL REGISTRATION NUMBER

ACTRN12619001329156.

Typical within and between person variability in non-invasive ventilator derived variables among clinically stable, long-term users

Background

Despite increasing capacity to remotely monitor non-invasive ventilation (NIV), how remote data varies from day to day and person to person is poorly described.

Methods

Single-centre, 2-month, prospective study of clinically stable adults on long-term NIV which aimed to document NIV-device variability. Participants were switched to a ventilator with tele-monitoring capabilities. Ventilation settings and masking were not altered. Raw, extensible markup language data files were provided directly from Philips Respironics (EncoreAnywhere). A nested analysis of variance was conducted on each ventilator variable to apportion the relative variation between and within participants.

Results

Twenty-nine people were recruited (four withdrew, one had insufficient data for analyses; 1364 days of data). Mean age was 54.0 years (SD 18.4), 58.3% male with body mass index of 37.0 kg/m² (13.7). Mean adherence was 8.53 (2.23) hours/day and all participants had adherence >4 hours/day. Variance in ventilator-derived indices was predominantly driven by differences between participants; usage (61% between vs 39% within), Apnoea–Hypopnoea Index (71% vs 29%), unintentional (64% vs 36%) and total leak (83% vs 17%), tidal volume (93% vs 7%), minute ventilation (92% vs 8%), respiratory rate (92% vs 8%) and percentage of triggered breaths (93% vs 7%).

Interpretation

In this clinically stable cohort, all device-derived indices were more varied between users than the day-to-day variation within individuals. We speculate that normative ranges and thresholds for clinical intervention need to be individualised, and further research is necessary to determine the clinically important relationships between clinician targets for therapy and patient-reported outcomes.

Respiratory function and respiratory complications in spinal cord injury: protocol for a prospective, multicentre cohort study in high-income countries

INTRODUCTION

Pneumonia is one of the leading complications and causes of death after a spinal cord injury (SCI). After a cervical or thoracic lesion, impairment of the respiratory muscles decreases respiratory function, which increases the risk of respiratory complications. Pneumonia substantially reduces patient's quality of life, may prolong inpatient rehabilitation time, increase healthcare costs or at worse, lead to early death. Respiratory function and coughing can be improved through various interventions after SCI, but the available evidence as to which aspect of respiratory care should be optimised is inconclusive. Furthermore, ability of respiratory function parameters to predict pneumonia risk is insufficiently established. This paper details the protocol for a large-scale, multicentre research project that aims to evaluate the ability of parameters of respiratory function to predict and understand variation in inpatient risk of pneumonia in SCI.

METHODS AND ANALYSIS

RESCOM, a prospective cohort study, began recruitment in October 2016 across 10 SCI rehabilitation centres from Australia, Austria, Germany, the Netherlands and Switzerland. Inpatients with acute SCI, with complete or incomplete cervical or thoracic lesions, 18 years or older and not/no more dependent on 24-hour mechanical ventilation within the first 3 months after injury are eligible for inclusion. The target sample size is 500 participants. The primary outcome is an occurrence of pneumonia; secondary outcomes include pneumonia-related mortality and quality of life. We will use the longitudinal data for prognostic models on inpatient pneumonia risk factors.

ETHICS AND DISSEMINATION

The study has been reviewed and approved by all local ethics committees of all participating centres. Study results will be disseminated to the scientific community through peer-reviewed journals and conference presentations, to the SCI community, other stakeholders and via social media, newsletters and engagement activities.

TRIAL REGISTRATION DETAILS

ClinicalTrials.gov NCT02891096.

The Effect of Hospital Discharge with Empiric Noninvasive Ventilation on Mortality in Hospitalized Patients with Obesity Hypoventilation Syndrome. An Individual Patient Data Meta-Analysis

Rationale: Hospitalized patients with acute-on-chronic hypercapnic respiratory failure due to obesity hypoventilation syndrome (OHS) have increased short-term mortality. It is unknown whether prescribing empiric positive airway pressure (PAP) at the time of hospital discharge reduces mortality compared with waiting for an outpatient evaluation (i.e., outpatient sleep study and outpatient PAP titration).Objectives: An international, multidisciplinary panel of experts developed clinical practice guidelines on OHS for the American Thoracic Society. The guideline panel asked whether hospitalized adult patients with acute-on-chronic hypercapnic respiratory failure suspected of having OHS, in whom the diagnosis has not yet been made, should be discharged from the hospital with or without empiric PAP treatment until the diagnosis of OHS is either confirmed or ruled out.Methods: A systematic review with individual patient data meta-analyses was performed to inform the guideline panel's recommendation. Grading of Recommendations, Assessment, Development, and Evaluation was used to summarize evidence and appraise quality.Results: The literature search identified 2,994 articles. There were no randomized trials. Ten studies met a priori study selection criteria, including two nonrandomized comparative studies and eight nonrandomized noncomparative studies. Individual patient data on hospitalized patients who survived to hospital discharge were obtained from nine of the studies and included a total of 1,162 patients (1,043 discharged with PAP and 119 discharged without PAP). Empiric noninvasive ventilation was prescribed in 91.5% of patients discharged on PAP, and the remainder received empiric continuous PAP. Discharge with PAP reduced mortality at 3 months (relative risk 0.12, 95% confidence interval 0.05-0.30, risk difference -14.5%). Certainty in the estimated effects was very low.Conclusions: Hospital discharge with PAP reduces mortality following acute-on-chronic hypercapnic respiratory failure in patients with OHS or suspected of having OHS. Well-designed clinical trials are needed to confirm this finding.

Using language descriptors to recognise delirium: a survey of clinicians and medical coders to identify delirium-suggestive words

OBJECTIVE

To develop a library of delirium-suggestive words.

DESIGN

Cross-sectional survey.

SETTING

Single tertiary referral hospital.

PARTICIPANTS

Medical, nursing and allied health staff and medical coders.

MAIN OUTCOME MEASURES

Frequency of graded response on a 5-point Likert scale to individual delirium-suggestive words.

RESULTS

Two-hundred and three complete responses were received from 227 survey respondents; the majority were medical and nursing staff (42.4% and 43.8% respectively), followed by allied health practitioners and medical coders (10.3% and 3.4%). Words that were "very likely" to suggest delirium were "confused/ confusion", "delirious", "disoriented/disorientation" and "fluctuating conscious state". Differences in word selection were noted based on occupational background, prior knowledge of delirium, and experience in caring for intensive care unit patients. Distractor words included in the survey were rated as "unlikely" or "very unlikely" by respondents as expected. Textual responses identified several other descriptors of delirium-suggestive words.

CONCLUSION

A comprehensive repertoire of delirium-suggestive words was validated using a multidisciplinary survey and new words suggested by respondents were added. The use of natural language processing algorithms may allow for earlier detection of delirium using our delirium library and be deployed for real-time decision making and clinical care.

Continuous Positive Airway Pressure Use for Obstructive Sleep Apnea in Acute, Traumatic Tetraplegia

OBJECTIVE

To describe continuous positive airway pressure (CPAP) use for treatment of obstructive sleep apnea (OSA) in acute tetraplegia, including adherence rates and associated factors.

DESIGN

Secondary analysis of CPAP data from a multinational randomized controlled trial.

SETTING

Inpatient rehabilitation units of 11 spinal cord injury centers.

PARTICIPANTS

People with acute, traumatic tetraplegia and OSA (N=79).

INTERVENTIONS

Autotitrating CPAP for OSA for 3 months.

MAIN OUTCOME MEASURES

Adherence measured as mean daily hours of use. Adherent (yes/no) was defined as an average of at least 4 hours a night throughout the study. Regression analyses determined associations between baseline factors and adherence. CPAP device pressure and leak data were analyzed descriptively.

RESULTS

A total of 79 participants from 10 spinal units (91% men; mean age ± SD, 46±16; 78±64d postinjury) completed the study in the treatment arm and 33% were adherent. Mean daily CPAP use ± SD was 2.9±2.3 hours. Better adherence was associated with more severe OSA (P=.04) and greater CPAP use in the first week (P<.01). Average 95th percentile pressure was low (9.3±1.7 cmH₂O) and 95th percentile leak was high (27.1±13.4 L/min).

CONCLUSION

Adherence to CPAP after acute, traumatic tetraplegia is low. Early acceptance of therapy and more severe OSA predict CPAP use over 3 months. People with acute tetraplegia require less pressure to treat their OSA than the nondisabled; however, air leak is high. These findings highlight the need for further investigation of OSA treatment in acute tetraplegia.

Understanding the clinical management of obstructive sleep apnoea in tetraplegia: a qualitative study using the theoretical domains framework

BACKGROUND

Clinical practice guidelines recommend further testing for people with tetraplegia and signs and symptoms of obstructive sleep apnoea (OSA), followed by treatment with positive airway pressure therapy. Little is known about how clinicians manage OSA in tetraplegia. The theoretical domains framework (TDF) is commonly used to identify determinants of clinical behaviours. This study aimed to describe OSA management practices in tetraplegia, and to explore factors influencing clinical practice.

METHODS

Semi-structured interviews were conducted with 20 specialist doctors managing people with tetraplegia from spinal units in Europe, UK, Canada, USA, Australia and New Zealand. Interviews were audiotaped for verbatim transcription. OSA management was divided into screening, diagnosis and treatment components for inpatient and outpatient services, allowing common practices to be categorised. Data were thematically coded to the 12 constructs of the TDF. Common beliefs were identified and comparisons were made between participants reporting different practices.

RESULTS

Routine screening for OSA signs and symptoms was reported by 10 (50%) doctors in inpatient settings and eight (40%) in outpatient clinics. Doctors commonly referred to sleep specialists for OSA diagnosis (9/20 in inpatients; 16/20 in outpatients), and treatment (12/20, 17/20). Three doctors reported their three spinal units were managing non-complicated OSA internally, without referral to sleep specialists. Ten belief statements representing six domains of the TDF were generated about screening. Lack of time and support staff (Environmental context and resources) and no prompts to screen for OSA (Memory, attention and decision processes) were commonly identified barriers to routine screening. Ten belief statements representing six TDF domains were generated for diagnosis and treatment behaviours. Common barriers to independent management practices were lack of skills (Skills), low confidence (Beliefs about capabilities), and the belief that OSA management was outside their scope of practice (Social/Professional role and identity). The three units independently managing OSA were well resourced with multidisciplinary involvement (Environmental context and resources), had 'clinical champions' to lead the program (Social influences).

CONCLUSION

Clinical management of OSA in tetraplegia is highly varied. Several influences on OSA management within spinal units have been identified, facilitating the development of future interventions aiming to improve clinical practice.

Randomised controlled trial of polysomnographic titration of noninvasive ventilation

Noninvasive ventilation (NIV) settings determined during wakefulness may produce patient–ventilator asynchrony (PVA) during sleep, causing sleep disruption and limiting tolerance. This study investigated whether NIV titrated with polysomnography (PSG) is associated with less PVA and sleep disruption than therapy titrated during daytime alone.

Treatment-naive individuals referred for NIV were randomised to control (daytime titration followed by sham polysomnographic titration) or PSG (daytime titration followed by polysomnographic titration) groups. Primary outcomes were PVA and arousal indices on PSG at 10 weeks. Secondary outcomes included adherence, gas exchange, symptoms and health-related quality of life (HRQoL).

In total, 60 participants were randomised. Most (88.3%) had a neuromuscular disorder and respiratory muscle weakness but minor derangements in daytime arterial blood gases. PVA events were less frequent in those undergoing polysomnographic titration (median (interquartile range (IQR)): PSG 25.7 (12–68) events·h−1versuscontrol 41.0 (28–182) events·h−1; p=0.046), but arousals were not significantly different (median (IQR): PSG 11.4 (9–19) arousals·h−1versuscontrol 14.6 (11–19) arousals·h−1; p=0.258). Overall adherence was not different except in those with poor early adherence (<4 h·day−1) who increased their use after polysomnographic titration (mean difference: PSG 95 (95% CI 29–161) min·day−1versuscontrol −23 (95% CI −86–39) min·day−1; p=0.01). Arterial carbon dioxide tension, somnolence and sleep quality improved in both groups. There were no differences in nocturnal gas exchange or overall measures of HRQoL.

NIV titrated with PSG is associated with less PVA but not less sleep disruption when compared with therapy titrated during daytime alone.

Development and feasibility testing of an online virtual reality platform for delivering therapeutic group singing interventions for people living with spinal cord injury

People with quadriplegia have a high risk for respiratory illness, social isolation and depression. Previous research has demonstrated that therapeutic singing interventions can not only improve breathing function and speech loudness, but also improve mood and social connectedness for people with quadriplegia. Face-to-face group attendance is difficult for this population due to difficulties with distance and travel. Online environments offer an accessible and cost-effective solution for people to connect with others without leaving their home. In a two-phase iterative design, we explored and tested different approaches for delivering online music therapy sessions with 12 patients from an inpatient spinal cord injury rehabilitation service. Six participants in Phase 1 trialled different virtual reality headsets and completed a short interview about their experience of the equipment and online singing trials. Outcomes from Phase 1 testing led to the development of a custom-built virtual reality application for online group music therapy sessions with low-latency audio. We tested the acceptability and feasibility of this platform in comparison to face-to-face and teleconference options for music therapy with six different patients. These participants completed three validated questionnaires: System Usability Scale, Quebec User Evaluation of Satisfaction with assistive Technology, and Psychosocial Impact of Assistive Devices Scale, and an interview about their experience. Questionnaire scores were good with mean ratings of 4.4 for Quebec User Evaluation of Satisfaction with assistive Technology, 53 for System Usability Scale and positive mean Psychosocial Impact of Assistive Devices Scale scores of 1.5 for competence, 2 for adaptability and 1.5 for self-esteem. Thematic analysis of post-session qualitative interviews revealed five themes: virtual reality was a positive experience, virtual reality was immersive and transportative, virtual reality reduced inhibitions about singing in front of others, virtual reality may reduce social cues, and the virtual reality equipment was comfortable, accessible and easy to use. Telehealth options, including a custom-designed virtual reality program, with low-latency audio are an acceptable and feasible mode of delivery for therapeutic singing interventions for people with spinal cord injury. Future non-inferiority research is needed to test online delivery modes for music therapy in comparison to face-to-face treatment.

Positive airway pressure for sleep-disordered breathing in acute quadriplegia: a randomised controlled trial

RATIONALE

Highly prevalent and severe sleep-disordered breathing caused by acute cervical spinal cord injury (quadriplegia) is associated with neurocognitive dysfunction and sleepiness and is likely to impair rehabilitation.

OBJECTIVE

To determine whether 3 months of autotitrating CPAP would improve neurocognitive function, sleepiness, quality of life, anxiety and depression more than usual care in acute quadriplegia.

METHODS AND MEASUREMENTS

Multinational, randomised controlled trial (11 centres) from July 2009 to October 2015. The primary outcome was neurocognitive (attention and information processing as measure with the Paced Auditory Serial Addition Task). Daytime sleepiness (Karolinska Sleepiness Scale) was a priori identified as the most important secondary outcome.

MAIN RESULTS

1810 incident cases were screened. 332 underwent full, portable polysomnography, 273 of whom had an apnoea hypopnoea index greater than 10. 160 tolerated at least 4 hours of CPAP during a 3-day run-in and were randomised. 149 participants (134 men, age 46±34 years, 81±57 days postinjury) completed the trial. CPAP use averaged 2.9±2.3 hours per night with 21% fully 'adherent' (at least 4 hours use on 5 days per week). Intention-to-treat analyses revealed no significant differences between groups in the Paced Auditory Serial Addition Task (mean improvement of 2.28, 95% CI -7.09 to 11.6; p=0.63). Controlling for premorbid intelligence, age and obstructive sleep apnoea severity (group effect -1.15, 95% CI -10 to 7.7) did not alter this finding. Sleepiness was significantly improved by CPAP on intention-to-treat analysis (mean difference -1.26, 95% CI -2.2 to -0.32; p=0.01).

CONCLUSION

CPAP did not improve Paced Auditory Serial Addition Task scores but significantly reduced sleepiness after acute quadriplegia.

TRIAL REGISTRATION NUMBER

ACTRN12605000799651.

Impact Of Spinal Cord Injury On Sleep: Current Perspectives

Sleep disorders are commonly encountered in people living with spinal cord injury (SCI). Primary sleep disorders such as sleep-disordered breathing (SDB), sleep-related movement disorders, circadian rhythm sleep-wake disorders, and insomnia disorder are common conditions after SCI but remain under-recognized, underdiagnosed and therefore remain untreated for a majority of patients. Sleep disturbances in people living with SCI are associated with significant impairments of daytime function and quality of life. Previous reviews have described findings related mainly to SDB but have not examined the relationship between other sleep disorders and SCI. This narrative review examines various sleep abnormalities and related functional and physical impairments in people living with SCI. It discusses new evidence pertaining to management, highlights existing limitations in the literature and recommends future directions for research.

Worth the effort? Weighing up the benefit and burden of continuous positive airway pressure therapy for the treatment of obstructive sleep apnoea in chronic tetraplegia

STUDY DESIGN

Mixed methods OBJECTIVES: Continuous positive airway pressure (CPAP) therapy is the recommended treatment for obstructive sleep apnoea (OSA). The aim of this study was to estimate CPAP adherence in people with tetraplegia and OSA, and to explore the barriers and facilitators to CPAP use.

SETTING

Hospital outpatient department in Melbourne, Australia METHODS: People with chronic tetraplegia and OSA were commenced with auto-titrating CPAP and supported for 1 month. Semi-structured interviews were conducted with participants at one month and analysed thematically. CPAP usage was measured at 1, 6 and 12 months, with "adherent" defined as achieving more than 4 h average per night.

RESULTS

Sixteen participants completed the study (80% male; mean age 56 (SD = 15)). Mean nightly CPAP use at one month was 3.1 h (SD = 2.5; 38% adherent), and at 6 months and 12 months were 2.6 h (SD = 2.8; 25% adherent) and 2.1 h (SD = 3.2; 25% adherent). The perceived benefit/burden balance strongly influenced ongoing use. Burden attributed to CPAP use was common, and included mask discomfort, and physical and emotional problems. Adherent participants were motivated by the immediate daytime benefits to mood, alertness and sleepiness. There was a tendency to not recognise symptoms of OSA until after they were treated.

CONCLUSION

CPAP use is challenging for people with tetraplegia, who experience substantial burden from using the device. When tolerated, the proximate benefits are substantial. People with tetraplegia need more intensive support for longer to help them overcome the burdens of CPAP and benefit from the treatment.

Diagnostic accuracy of a two-stage model for detecting obstructive sleep apnoea in chronic tetraplegia

BACKGROUND

Obstructive sleep apnoea (OSA) is highly prevalent in people with spinal cord injury (SCI). Polysomnography (PSG) is the gold-standard diagnostic test for OSA, however PSG is expensive and frequently inaccessible, especially in SCI. A two-stage model, incorporating a questionnaire followed by oximetry, has been found to accurately detect moderate to severe OSA (MS-OSA) in a non-disabled primary care population. This study investigated the accuracy of the two-stage model in chronic tetraplegia using both the original model and a modified version for tetraplegia.

METHODS

An existing data set of 78 people with tetraplegia was used to modify the original two-stage model. Multivariable analysis identified significant risk factors for inclusion in a new tetraplegia-specific questionnaire. Receiver operating characteristic (ROC) curve analyses of the questionnaires and oximetry established thresholds for diagnosing MS-OSA. The accuracy of both models in diagnosing MS-OSA was prospectively evaluated in 100 participants with chronic tetraplegia across four international SCI units.

RESULTS

Injury completeness, sleepiness, self-reported snoring and apnoeas were included in the modified questionnaire, which was highly predictive of MS-OSA (ROC area under the curve 0.87 (95% CI 0.79 to 0.95)). The 3% oxygen desaturation index was also highly predictive (0.93 (0.87-0.98)). The two-stage model with modified questionnaire had a sensitivity and specificity of 83% (66-93) and 88% (75-94) in the development group, and 77% (65-87) and 81% (68-90) in the validation group. Similar results were demonstrated with the original model.

CONCLUSION

Implementation of this simple alternative to full PSG could substantially increase the detection of OSA in patients with tetraplegia and improve access to treatments.

TRIAL REGISTRATION NUMBER

Results, ACTRN12615000896572 (The Australian and New Zealand Clinical Trials Registry) and pre-results, NCT02176928 (clinicaltrials.gov).

Periodic limb movements in tetraplegia

OBJECTIVE

To establish the prevalence of Periodic Limb Movements during Sleep (PLMS) in patients with tetraplegia, controlling for obstructive sleep apnea. To explore whether demographic and injury characteristics affect PLMS.

STUDY DESIGN

Retrospective cohorts.

SETTING AND PARTICIPANTS

One hundred seventy-three participants with acute (<12 months) and 92 with chronic (>12 months) tetraplegia who underwent full overnight diagnostic sleep studies.

INTERVENTIONS AND OUTCOME MEASURES

Two hundred sixty-two sleep study recordings were included. A randomly selected subgroup of 21 studies was assessed for PLM during wakefulness. Data were analysed according to the current American Academy of Sleep Medicine guidelines.

RESULTS

Of the participants, 41.6% (43(15.7) years and 14.9% female) had a motor and sensory complete lesion. Sleep was poor with both OSA (87.8% with apnea hypopnoea index ≥ 5) and PLMS (58.4% with PLMS per hour PLMSI > 15) highly prevalent. There was no difference in the PLMSI between those with OSA (36.3(39.8)) or without (42.2(37.7), P = 0.42). PLMS were evident during REM and NREM sleep in all of the 153 patients with PLMSI > 15. All 21 participants in the subgroup of studies analysed for the PLM during quiet wakefulness, exhibited limb movements. None of the modelled variables (injury completeness, gender, OSA severity or time since injury) significantly predicted a PLMSI > 15 (P = 0.343).

CONCLUSION

In conclusion, this study confirms the high prevalence of PLM in tetraplegia and the presence of leg movements in NREM and REM sleep along with wakefulness after controlling for OSA. No associations between the presence of PLMS and patient characteristics or injury specific aspects were found.

Genioglossus reflex responses to negative upper airway pressure are altered in people with tetraplegia and obstructive sleep apnoea

KEY POINTS

Protective reflexes in the throat area (upper airway) are crucial for breathing. Impairment of these reflexes can cause breathing problems during sleep such as obstructive sleep apnoea (OSA). OSA is very common in people with spinal cord injury for unknown reasons. This study shows major changes in protective reflexes that serve to keep the upper airway open in response to suction pressures in people with tetraplegia and OSA. These results help us understand why OSA is so common in people with tetraplegia and provide new insight into how protective upper airway reflexes work more broadly.

ABSTRACT

More than 60% of people with tetraplegia have obstructive sleep apnoea (OSA). However, the specific causes are unknown. Genioglossus, the largest upper-airway dilator muscle, is important in maintaining upper-airway patency. Impaired genioglossus muscle function following spinal cord injury may contribute to OSA. This study aimed to determine if genioglossus reflex responses to negative upper-airway pressure are altered in people with OSA and tetraplegia compared to non-neurologically impaired able-bodied individuals with OSA. Genioglossus reflex responses measured via intramuscular electrodes to ∼60 brief (250 ms) pulses of negative upper-airway pressure (∼-15 cmH₂ O at the mask) were compared between 13 participants (2 females) with tetraplegia plus OSA and 9 able-bodied controls (2 females) matched for age and OSA severity. The initial short-latency excitatory reflex response was absent in 6/13 people with tetraplegia and 1/9 controls. Genioglossus reflex inhibition in the absence of excitation was observed in three people with tetraplegia and none of the controls. When the excitatory response was present, it was significantly delayed in the tetraplegia group compared to able-bodied controls: excitation onset latency (mean ± SD) was 32 ± 16 vs. 18 ± 9 ms, P = 0.045; peak excitation latency was 48 ± 17 vs. 33 ± 8 ms, P = 0.038. However, when present, amplitude of the excitation response was not different between groups, 195 ± 26 vs. 219 ± 98% at baseline, P = 0.55. There are major differences in genioglossus reflex morphology and timing in response to rapid changes in airway pressure in people with tetraplegia and OSA. Altered genioglossus function may contribute to the increased risk of OSA in people with tetraplegia. The precise mechanisms mediating these differences are unknown.

Facilitators and Barriers to International Collaboration in Spinal Cord Injury: Results from a Survey of Clinicians and Researchers

International collaboration in spinal cord injury (SCI) research is necessary to overcome the challenges often encountered by clinicians and researchers, including participant recruitment, high cost, and the need for specialized expertise. However, international collaboration poses its own obstacles. The objective of this study was to conduct an international online survey to assess barriers and facilitators to international SCI clinical research, potential initiatives to facilitate future collaborations, and the use of SCI-specific data sets and standards. Results were analyzed using descriptive statistics. Of 364 total respondents, 213 completed the survey, with the majority of these participants based in North America (38%), Asia (22%), Europe (18%), and Oceania (16%). Over half had more than 10 years of experience in SCI research or clinical practice (57%) and 60% had previous experience with international collaborations. Funding was identified as a top barrier (82%), a facilitator (93%), and a proposed future initiative (97%). Communication and technology were also identified as strong facilitators and proposed future initiatives. The International Standards for Neurological Classification of SCI were used by 69% of participants, the International Standards to document remaining Autonomic Function after SCI by 13% of participants, and the International SCI Data Sets by 45% of participants. As the need for international collaborations in SCI research increases, it is important to identify how clinicians and researchers can be supported by SCI consumer and professional organizations, funders, and networks. Furthermore, unique solutions to overcome modifiable barriers and creation of new facilitators are also needed.

Light sensors for objective light measurement in ambulatory polysomnography

Ambulatory polysomnography (PSG) does not commonly include an objective measure of light to determine the time of lights off (Loff), and thus cannot be used to calculate important indices such as sleep onset latency and sleep efficiency. This study examined the technical specifications and appropriateness of a prototype light sensor (LS) for use in ambulatory Compumedics Somte PSG.Two studies were conducted. The first examined the light measurement characteristics of the LS when used with a portable PSG device, specifically recording trace range, linearity, sensitivity, and stability. This involved the LS being exposed to varying incandescent and fluorescent light levels in a light controlled room. Secondly, the LS was trialled in 24 home and 12 hospital ambulatory PSGs to investigate whether light levels in home and hospital settings were within the recording range of the LS, and to quantify the typical light intensity reduction at the time of Loff. A preliminary exploration of clinical utility was also conducted. Linearity between LS voltage and lux was demonstrated, and the LS trace was stable over 14 hours of recording. The observed maximum voltage output of the LS/PSG device was 250 mV, corresponding to a maximum recording range of 350 lux and 523 lux for incandescent and fluorescent light respectively. At the time of Loff, light levels were within the recording range of the LS, and on average dropped by 72 lux (9–245) in the home and 76 lux (4–348) in the hospital setting. Results suggest that clinical utility was greatest in hospital settings where patients are less mobile. The LS was a simple and effective objective marker of light level in portable PSG, which can be used to identify Loff in ambulatory PSG. This allows measurement of additional sleep indices and support with clinical decisions.

Magnetic resonance imaging of the upper airway in patients with quadriplegia and obstructive sleep apnea

The aim of this study was to investigate upper airway anatomy in quadriplegics with obstructive sleep apnea. Fifty subjects were recruited from three hospitals in Australia: people with quadriplegia due to spinal cord injury and obstructive sleep apnea (n = 11), able-bodied people with obstructive sleep apnea (n = 18), and healthy, able-bodied controls (n = 19). All underwent 3-Tesla magnetic resonance imaging of their upper airway. A subgroup (n = 34) received a topical vasoconstrictor, phenylephrine and post-phenylephrine magnetic resonance imaging. Mixed-model analysis indicated no significant differences in total airway lumen volume between the three groups (P = 0.086). Spinal cord injury-obstructive sleep apnea subjects had a significantly larger volume of soft palate (P = 0.020) and retroglossal lateral pharyngeal walls (P = 0.043) than able-bodied controls. Able-bodied-obstructive sleep apnea subjects had a smaller mandible volume than spinal cord injury-obstructive sleep apnea subjects and able-bodied control subjects (P = 0.036). No differences were seen in airway length between groups when controlling for height (P = 0.055). There was a marginal increase in velopharyngeal volume across groups post-phenylephrine (P = 0.050), and post hoc testing indicated the difference was confined to the able-bodied-obstructive sleep apnea group (P < 0.001). No other upper airway structures showed significant changes with phenylephrine administration. In conclusion, people with obstructive sleep apnea and quadriplegia do not have a structurally smaller airway than able-bodied subjects. They did, however, have greater volumes of soft palate and lateral pharyngeal walls, possibly due to greater neck fat deposition. The acute response to upper airway topical vasoconstriction was not enhanced in those with obstructive sleep apnea and quadriplegia. Changes in upper airway anatomy likely contribute to the high incidence in obstructive sleep apnea in quadriplegic subjects.

Neuropsychological Function in Patients With Acute Tetraplegia and Sleep Disordered Breathing

Study objectives

To investigate the relationship between apnea severity and neuropsychological function in patients with acute-onset tetraplegia and sleep disordered breathing.

Methods

Polysomnography and neuropsychological testing were performed on 104 participants (age M = 45.60, SD = 16.38; 10 female) across 11 international sites, 2 months postinjury (M = 60.70 days, SD = 39.48). Neuropsychological tests assessed attention, information processing, executive function, memory, learning, mood, and quality of life.

Results

More severe sleep apnea was associated with poorer attention, information processing, and immediate recall. Deficits did not extend to memory. Higher preinjury intelligence and being younger reduced the associations with sleep disordered breathing; however, these protective factors were insufficient to counter the damage to attention, immediate recall, and information processing associated with sleep disordered breathing.

Conclusions

These data suggest that new spinal cord injury may function as a model of "acute sleep apnea" and that more widespread sleep apnea-related deficits, including memory, may only be seen with longer exposure to apnea. These findings have important implications for functioning and skill acquisition during rehabilitation and, as such, highlight the importance of sleep health following tetraplegia.

Respiratory problems and management in people with spinal cord injury

Spinal cord injury (SCI) is characterised by profound respiratory compromise secondary to the level of loss of motor, sensory and autonomic control associated with the injury. This review aims to detail these anatomical and physiological changes after SCI, and outline their impact on respiratory function. Injury-related impairments in strength substantially alter pulmonary mechanics, which in turn affect respiratory management and care. Options for treatments must therefore be considered in light of these limitations.

KEY POINTS

Respiratory impairment following spinal cord injury (SCI) is more severe in high cervical injuries, and is characterised by low lung volumes and a weak cough secondary to respiratory muscle weakness.Autonomic dysfunction and early-onset sleep disordered breathing compound this respiratory compromise.The mainstays of management following acute high cervical SCI are tracheostomy and ventilation, with noninvasive ventilation and assisted coughing techniques being important in lower cervical and thoracic level injuries.Prompt investigation to ascertain the extent of the SCI and associated injuries, and appropriate subsequent management are important to improve outcomes.

EDUCATIONAL AIMS

To describe the anatomical and physiological changes after SCI and their impact on respiratory function.To describe the changes in respiratory mechanics seen in cervical SCI and how these changes affect treatments.To discuss the relationship between injury level and respiratory compromise following SCI, and describe those at increased risk of respiratory complications.To present the current treatment options available and their supporting evidence.

Nasal Resistance Is Elevated in People with Tetraplegia and Is Reduced by Topical Sympathomimetic Administration

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is common in individuals with tetraplegia and associated with adverse health outcomes. The causes of the high prevalence of OSA in this population are unknown, but it is important to understand as standard treatments are poorly tolerated in tetraplegia. Nasal congestion is common in tetraplegia, possibly because of unopposed parasympathetic activity. Further, nasal obstruction can induce OSA in healthy individuals. We therefore aimed to compare nasal resistance before and after topical administration of a sympathomimetic between 10 individuals with tetraplegia (T) and 9 able-bodied (AB) controls matched for OSA severity, gender, and age.

METHODS

Nasal, pharyngeal, and total upper airway resistance were calculated before and every 2 minutes following delivery of ≈0.05 mL of 0.5% atomized phenylephrine to the nostrils and pharyngeal airway. The surface tension of the upper airway lining liquid was also assessed.

RESULTS

At baseline, individuals with tetraplegia had elevated nasal resistance (T = 7.0 ± 1.9, AB = 3.0 ± 0.6 cm H₂O/L/s), that rapidly fell after phenylephrine (T = 2.3 ± 0.4, p = 0.03 at 2 min) whereas the able-bodied did not change (AB = 2.5 ± 0.5 cm H₂O/L/s, p = 0.06 at 2 min). Pharyngeal resistance was non-significantly higher in individuals with tetraplegia than controls at baseline (T = 2.6 ± 0.9, AB = 1.2 ± 0.4 cm H₂O/L/s) and was not altered by phenylephrine in either group. The surface tension of the upper airway lining liquid did not differ between groups (T = 64.3 ± 1.0, AB = 62.7 ± 0.6 mN/m).

CONCLUSIONS

These data suggest that the unopposed parasympathetic activity in tetraplegia increases nasal resistance, potentially contributing to the high occurrence of OSA in this population.