Life expectancy of ventilator-dependent persons with spinal cord injuries

Sexually dimorphic extracellular vesicle responses after chronic spinal cord injury are associated with neuroinflammation and neurodegeneration in the aged brain

BACKGROUND

Medical advances have made it increasingly possible for spinal cord injury (SCI) survivors to survive decades after the insult. But how SCI affects aging changes and aging impacts the injury process have received limited attention. Extracellular vesicles (EVs) are recognized as critical mediators of neuroinflammation after CNS injury, including at a distance from the lesion site. We have previously shown that SCI in young male mice leads to robust changes in plasma EV count and microRNA (miR) content. Here, our goal was to investigate the impact of biological sex and aging on EVs and brain after SCI.

METHODS

Young adult age-matched male and female C57BL/6 mice were subjected to SCI. At 19 months post-injury, total plasma EVs were isolated by ultracentrifugation and characterized by nanoparticle tracking analysis (NTA). EVs miR cargo was examined using the Fireplex® assay. The transcriptional changes in the brain were assessed by a NanoString nCounter Neuropathology panel and validated by Western blot (WB) and flow cytometry (FC). A battery of behavioral tests was performed for assessment of neurological function.

RESULTS

Transcriptomic changes showed a high number of changes between sham and those with SCI. Sex-specific changes were found in transcription networks related to disease association, activated microglia, and vesicle trafficking. FC showed higher microglia and myeloid counts in the injured tissue of SCI/Female compared to their male counterparts, along with higher microglial production of ROS in both injured site and the brain. In the latter, increased levels of TNF and mitochondrial membrane potential were seen in microglia from SCI/Female. WB and NTA revealed that EV markers are elevated in the plasma of SCI/Male. Particle concentration in the cortex increased after injury, with SCI/Female showing higher counts than SCI/Male. EVs cargo analysis revealed changes in miR content related to injury and sex. Behavioral testing confirmed impairment of cognition and depression at chronic time points after SCI in both sexes, without significant differences between males and females.

CONCLUSIONS

Our study is the first to show sexually dimorphic changes in brain after very long-term SCI and supports a potential sex-dependent EV-mediated mechanism that contributes to SCI-induced brain changes.

Longitudinal changes in employment, health, participation, and quality-of-life and the relationships with long-term survival after spinal cord injury

STUDY DESIGN

Cohort study.

OBJECTIVE

To identify five-year longitudinal changes in employment, health, participation, and quality-of-life outcomes (QOL) among participants with chronic spinal cord injury (SCI) and to compare the amount of change in these outcomes between those surviving and those not surviving until follow-up.

METHODS

Participants were 1157 individuals from the SCI Longitudinal Aging Study, who have completed at least two self-report assessments separated by five-year intervals. The main outcome measures were 13 indicators related to employment, health, participation, and QOL/psychosocial indicators. Survival status measured at follow-up.

RESULTS

Those who survived to follow up had a history indicating a greater likelihood of employment, better health, participation, and QOL/psychosocial indicators. Among survivors, longitudinal declines were limited to the percent employed and participation indicators, whereas those deceased by follow-up had significant undesirable changes in employment, participation, health, and QOL/psychosocial indicators. More specifically, compared to the survivors, those deceased by follow-up experienced a greater increase in hospitalizations, decreases in nights away from home, and declines in global satisfaction over the five-year interval.

CONCLUSIONS

Longitudinal declines in employment and some aspects of participation are common among long-term survivors and may be part of the natural course of outcomes after SCI. However, more dramatic increases in hospitalizations, fewer nights away from home, and declining satisfaction may be red flags for declining longevity.

Rehabilitation interventions for weaning from mechanical ventilation in patients with spinal cord injury: A systematic review

BACKGROUND

Despite the fact that weaning from mechanical ventilation (MV) is one of the main rehabilitation goals in patients with spinal cord injury (SCI), controversies are still open about the optimal rehabilitation approach.

OBJECTIVE

This systematic review aimed at characterizing the rehabilitation interventions currently available to optimize weaning from MV in SCI patients.

METHODS

On April 12nd, 2022, a systematic literature search was performed in PubMed, Scopus, Web of Science, Cochrane, and PEDro, identifying studies assessing MV patients with SCI undergoing pulmonary rehabilitation. The primary outcomes were weaning duration, MV duration, and weaning success rate. Secondary outcomes were pulmonary function, extubation or decannulation time, length of stay, and safety.

RESULTS

Out of 413 records, 14 studies were included (2 randomized controlled trials, 7 observational studies, and 5 case reports). Most of the studies assessed a comprehensive rehabilitation approach, including high tidal volume ventilation, positioning, mechanical lung recruitment maneuvers, secretion management strategies, respiratory muscle training, and electrical stimulation.

CONCLUSION

Our findings suggested that a comprehensive rehabilitation intervention might have a role in reducing MV duration in patients with SCI. Further studies are needed to better characterize the optimal rehabilitation strategies for enhancing functional recovery of patients with SCI.

Social participation as a mediator of the relationships of socioeconomic factors and longevity after traumatic spinal cord injury

STUDY DESIGN

Cohort study.

OBJECTIVE

Previous research has indicated that socioeconomic factors affect longevity after traumatic spinal cord injury (SCI). Our purpose was to evaluate whether social participation mediates the relationship between socioeconomic factors and survival status after SCI.

SETTING

Medical university in the southeastern United States.

METHODS

Participants (N = 1540) met the following inclusion criteria: traumatic SCI of at least 1-year duration, minimum of 18 years of age, and having residual impairment from SCI. The main outcome measures were a) survival status as of December 31, 2019, identified by the National Death Index (NDI) search, b) socioeconomic status (SES), measured by education, employment status, and family income, and c) participation, measured by marital/relationship status, hours out of bed per day, days leaving home per week, and nights away home during the past year.

RESULTS

Thirty nine percent of participants (n = 602) were decreased by the end of 2019. Socioeconomic factors were associated with longevity controlling for demographic, injury characteristics, and health status. However, the association of SES with longevity was mediated by three social participation mobility indicators (hours out of bed, days out of house, and nights away from home), such that SES was no longer significantly related to longevity after inclusion of the participation variables.

CONCLUSIONS

Although socioeconomic factors are related to longevity, their relationship appears to be mediated by social participation mobility indicators. Intervention studies are needed to address the modifiable factors that may promote longevity, including promoting an active lifestyle.

Demographic and Health Profiles of People Living With Traumatic Spinal Cord Injury in the United States During 2015-2019: Findings from the Spinal Cord Injury Model Systems Database

OBJECTIVE

To estimate the population profile of people living with traumatic spinal cord injury (TSCI) to help evaluate health care needs of this aging population.

DESIGN

Cross-sectional study.

SETTING

SCI Model Systems (SCIMS) centers in the United States.

PARTICIPANTS

Individuals (N=20,437) who: (1) incurred a TSCI between 1972 and 2019, (2) were initially treated at one of the SCIMS centers, and (3) were alive during the period from 2015 to 2019.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Demographics, injury characteristics, health conditions, and social participation, as compared with previous estimates in 2008 and general population statistics in 2017.

RESULTS

People living with TSCI during the period from 2015-2019 (mean years since injury, 18y; 79.4% male, and 62.5% White) were older (51.6 vs 45.0y) and had a higher percentage of C1-C4 (21.9% vs 17.0%) and American Spinal Injury Association Impairment Scale D injuries (31.5% vs 26.0%) compared with the 2008 TSCI population profile. Although the proportion of people with a bachelor's degree or higher was similar between the TSCI and general US populations (30.7% vs 32.0%), the employment rate was lower in the TSCI population (24.0% vs 59.5%). People are affected by various medical problems over time post TSCI. The prevalence of pain and urinary tract infection remained high over postinjury years, at 86.1% and 52.6%, respectively. Rehospitalization and depression were most common during the first year (34.9% and 22.3%, respectively), and pressure injury was more common among those 20 years or more postinjury (>30.0%). Health conditions declined with advanced age, including self-perceived health, diabetes, and institutional residence. People who survived TSCI for years, however, had relatively good degrees of independence and social participation.

CONCLUSION

Study findings highlight the need for greater involvement of primary care providers and geriatricians in the continuity of care for SCI to promote healthy aging. Improvement in employment should also be the target in promoting social participation and quality of life.

A systematic review of suicidal ideation and behaviors among adults with spinal cord injury

CONTEXT

Suicide is a public health crisis within the United States. Individuals with spinal cord injury (SCI) are vulnerable to negative outcomes such as suicide.

OBJECTIVE

This systematic review describes frequency of suicidal ideation (SI) and behaviors (suicide attempt [SA] and deaths) among samples of adults living with SCI. Associated risk and protective factors of SI and suicidal behaviors were also explored.

METHODS

On July 7, 2021, OVID Medline, EMBASE, OVID PsycINFO, Web of Science Core Collection, CINAHL, Cochrane Library, and Google Scholar databases were searched for SI, SA, and deaths by suicide among adults with a history of SCI. Risk of bias (RoB) was assessed using the Effective Public Health Practice Project (EPHPP) quality assessment tool. Results were synthesized descriptively considering the likely impact of RoB. The updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 reporting method was used.

RESULTS

Sixty-nine articles were included. Frequency of SI and SAs within study samples ranged from 4% to 67%, and 0% to approximately 66%, respectively. While assessment methods for SI and SA widely varied, suicide deaths data sources were more consistent. Studies assessing SI and SA generally had high RoB and the overall strength of evidence was low. Stronger observational study designs assessing death by suicide had low RoB and the overall strength of evidence was high. Very few studies examined protective factors.

DISCUSSION

Findings support previous work. Quality of evidence, and therefore confidence in the frequency of these outcomes, was impacted by the use of assessment measures without sufficient psychometric properties. The field will benefit from use of psychometrically sound measures to assess for SI, SA and suicide deaths. Furthermore, additional work is needed to elucidate risk and protective factors and to clearly characterize samples to increase generalizability of findings to the larger SCI community, including standardized reporting of SCI characteristics (e.g. use of American Spinal Injury Association classification system). Ultimately, improved suicide assessment and risk management is expected to prevent suicide among those living with SCI.

REGISTRATION

CRD42020164686.

Ethical attitudes in neurosurgery at the height of the COVID-19 pandemic

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Pandemic conditions imposed withholding or withdrawing neurosurgical treatment.

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Variation exist in the management of intracranial haemorrhage or TBI during a pandemic.

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Triaging guidelines for neurosurgical patients need to be established.

Spinal cord injury and degenerative cervical myelopathy

Spinal cord injury (SCI) often results in impaired respiratory function. Paresis or paralysis of inspiratory and expiratory muscles can lead to respiratory dysfunction depending on the level and severity of the injury, which can affect the management and care of SCI patients. Respiratory dysfunction after SCI is more severe in high cervical injuries, with vital capacity (VC) being an essential indicator of overall respiratory health. Respiratory complications include hypoventilation, a reduction in surfactant production, mucus plugging, atelectasis, and pneumonia. Respiratory management includes mechanical ventilation and tracheostomy in high cervical SCI, while noninvasive ventilation is more common in patients with lower cervical and thoracic injuries. Mechanical ventilation can negatively impact the function of the diaphragm and weaning should start as soon as possible. Patients can sometimes be weaned from mechanical ventilation with assistance of electrical stimulation of the phrenic nerve or the diaphragm. Respiratory muscle training regimens may also improve patients' inspiratory function following SCI. Despite the critical advances in preventing, diagnosing, and treating respiratory complications, they continue to significantly affect persons living with SCI. Additional studies of interventions to reduce respiratory complications are likely to further decrease the morbidity and mortality associated with these injuries.

Cause of Death Trends Among Persons With Spinal Cord Injury in the United States: 1960-2017

OBJECTIVE

To identify trends in causes of death after spinal cord injury (SCI) that could enhance understanding of why life expectancy after SCI has not improved in the last 3 decades.

DESIGN

Cohort study.

SETTING

Twenty-nine SCI Model Systems and 3 Shriners Hospitals.

PARTICIPANTS

Individuals with traumatic SCI (N=49,266) enrolled in the SCI Collaborative Survival Study Database between 1973 and 2017.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Age-standardized cause-specific SCI mortality rates and 95% confidence intervals were calculated for 5 time intervals (1960-1979, 1980-1989, 1990-1999, 2000-2009, and 2010-2017).

RESULTS

A total of 17,249 deaths occurred in 797,226 person-years of follow-up. Since 2010, the highest mortality rate was for respiratory diseases, followed by heart disease, cancer, infective and parasitic diseases (primarily septicemia), and unintentional injuries. Mortality rates for respiratory diseases, cancer, stroke, urinary diseases, and digestive diseases, initially decreased significantly but remained relatively stable since 1980, whereas essentially no progress occurred for infective and parasitic diseases. Mortality rates for heart disease, pulmonary embolus, and suicide decreased significantly throughout the entire study period, but were offset by increases in mortality rates for endocrine (primarily diabetes), nutritional, and metabolic diseases, as well as unintentional injuries. From 2010 to 2017, the overall age-standardized mortality rate was 3 times higher for individuals with SCI than the general population, ranging from 27% higher for cancer to 9 times higher for infective and parasitic diseases.

CONCLUSION

Improving life expectancy after SCI will require: (1) reducing mortality rates from respiratory diseases and septicemia that have remained high, (2) reversing current trends in diabetes and unintentional injury deaths, and (3) continuing to reduce mortality from heart disease and other leading causes.

Separation from mechanical ventilation and survival after spinal cord injury: a systematic review and meta-analysis

Background

Prolonged need for mechanical ventilation greatly impacts life expectancy of patients after spinal cord injury (SCI). Weaning outcomes have never been systematically assessed. In this systematic review and meta-analysis, we aimed to investigate the probability of weaning success, duration of mechanical ventilation, mortality, and their predictors in mechanically ventilated patients with SCI.

Methods

We searched six databases from inception until August 2021 for randomized-controlled trials and observational studies enrolling adult patients (≥ 16 years) with SCI from any cause requiring mechanical ventilation. Titles and abstracts were screened independently by two reviewers. Full texts of the identified articles were then assessed for eligibility. Data were extracted independently and in duplicate by pairs of authors, using a standardized data collection form. Synthetic results are reported as meta-analytic means and proportions, based on random effects models.

Results

Thirty-nine studies (14,637 patients, mean age 43) were selected. Cervical lesions were predominant (12,717 patients had cervical lesions only, 1843 in association with other levels’ lesions). Twenty-five studies were conducted in intensive care units (ICUs), 14 in rehabilitative settings.

In ICU, the mean time from injury to hospitalization was 8 h [95% CI 7–9], mean duration of mechanical ventilation 27 days [20–34], probability of weaning success 63% [45–78] and mortality 8% [5–11]. Patients hospitalized in rehabilitation centres had a greater number of high-level lesions (C3 or above), were at 40 days [29–51] from injury and were ventilated for a mean of 97 days [65–128]; 82% [70–90] of them were successfully weaned, while mortality was 1% [0–19].

Conclusions

Although our study highlights the lack of uniform definition of weaning success, of clear factors associated with weaning outcomes, and of high-level evidence to guide optimal weaning in patients with SCI, it shows that around two-thirds of mechanically ventilated patients can be weaned in ICU after SCI. A substantial gain in weaning success can be obtained during rehabilitation, with additional duration of stay but minimal increase in mortality. The study is registered with PROSPERO (CRD42020156788).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-021-00938-x.

Comparison of wire and disc electrodes to electrically activate the inspiratory muscles in dogs

OBJECTIVE

To compare the effectiveness of wire versus disc electrodes to activate the inspiratory muscles via high frequency spinal cord stimulation.

DESIGN

Animal study.

SETTING

Research laboratory.

ANIMALS

Dogs (n = 5) INTERVENTIONS: In separate trials, spinal cord stimulation (SCS) was applied via disc (DE) and two parallel wire electrodes (WE) on the ventral epidural space at the T2-T3 spinal region.

MAIN OUTCOME MEASURE(S)

Airway pressure (P) and inspired volume (V) generation following stimulation with DE and WE were compared. Given our previous success with (DE), outcome variables with this electrode were used as our gold standard to which all comparisons were made.

RESULTS

Two configurations of WE using monopolar stimulation (MS) resulted in P and V that were similar to those generated with MS with DE. For example, MS with parallel WE connected together to function as a common cathode (Y-connection) and a 2-channel system (separate cathodes with a remote ground), resulted in P that were 91 ± 6 and 92 ± 4%, respectively, of those achieved with DE (NS for both). Bipolar stimulation with parallel WE using a Y-connection and with a 2-channel system, resulted in P that were 96 ± 4 and 94 ± 4%, of the P achieved with DE (NS for both).

CONCLUSION(S)

These results suggest that specific configurations of WE, which can be placed via minimally invasive techniques, provide comparable activation of the inspiratory muscles compared to DE and may be a useful technique to restore ventilatory support in persons with spinal cord injury.

Novel Influences of Sex and APOE Genotype on Spinal Plasticity and Recovery of Function after Spinal Cord Injury

Spinal cord injuries can abolish both motor and sensory function throughout the body. Spontaneous recovery after injury is limited and can vary substantially between individuals. Despite an abundance of therapeutic approaches that have shown promise in preclinical models, there is currently a lack of effective treatment strategies that have been translated to restore function after spinal cord injury (SCI) in the human population. We hypothesized that sex and genetic background of injured individuals could impact how they respond to treatment strategies, presenting a barrier to translating therapies that are not tailored to the individual. One gene of particular interest is APOE, which has been extensively studied in the brain because of its allele-specific influences on synaptic plasticity, metabolism, inflammation, and neurodegeneration. Despite its prominence as a therapeutic target in brain injury and disease, little is known about how it influences neural plasticity and repair processes in the spinal cord. Using humanized mice, we examined how the ε3 and ε4 alleles of APOE influence the efficacy of therapeutic intermittent hypoxia (IH) in inducing spinally-mediated plasticity after cervical SCI (cSCI). IH is sufficient to enhance plasticity and restore motor function after experimental SCI in genetically similar rodent populations, but its effect in human subjects is more variable (Golder and Mitchell, 2005; Hayes et al., 2014). Our results demonstrate that both sex and APOE genotype determine the extent of respiratory motor plasticity that is elicited by IH, highlighting the importance of considering these clinically relevant variables when translating therapeutic approaches for the SCI community.

ICU Management of Trauma Patients

OBJECTIVES

To describe the current state of the art regarding management of the critically ill trauma patient with an emphasis on initial management in the ICU.

DATA SOURCES AND STUDY SELECTION

A PubMed literature review was performed for relevant articles in English related to the management of adult humans with severe trauma. Specific topics included airway management, hemorrhagic shock, resuscitation, and specific injuries to the chest, abdomen, brain, and spinal cord.

DATA EXTRACTION AND DATA SYNTHESIS

The basic principles of initial management of the critically ill trauma patients include rapid identification and management of life-threatening injuries with the goal of restoring tissue oxygenation and controlling hemorrhage as rapidly as possible. The initial assessment of the patient is often truncated for procedures to manage life-threatening injuries. Major, open surgical procedures have often been replaced by nonoperative or less-invasive approaches, even for critically ill patients. Consequently, much of the early management has been shifted to the ICU, where the goal is to continue resuscitation to restore homeostasis while completing the initial assessment of the patient and watching closely for failure of nonoperative management, complications of procedures, and missed injuries.

CONCLUSIONS

The initial management of critically ill trauma patients is complex. Multiple, sometimes competing, priorities need to be considered. Close collaboration between the intensivist and the surgical teams is critical for optimizing patient outcomes.

Mechanisms of compensatory plasticity for respiratory motor neuron death

Respiratory motor neuron death arises from multiple neurodegenerative and traumatic neuromuscular disorders. Despite motor neuron death, compensatory mechanisms minimize its functional impact by harnessing intrinsic mechanisms of compensatory respiratory plasticity. However, the capacity for compensation eventually reaches limits and pathology ensues. Initially, challenges to the system such as increased metabolic demand reveal sub-clinical pathology. With greater motor neuron loss, the eventual result is de-compensation, ventilatory failure, ventilator dependence and then death. In this brief review, we discuss recent advances in our understanding of mechanisms giving rise to compensatory respiratory plasticity in response to respiratory motor neuron death including: 1) increased central respiratory drive, 2) plasticity in synapses on spared phrenic motor neurons, 3) enhanced neuromuscular transmission and 4) shifts in respiratory muscle utilization from more affected to less affected motor pools. Some of these compensatory mechanisms may prolong breathing function, but hasten the demise of surviving motor neurons. Improved understanding of these mechanisms and their impact on survival of spared motor neurons will guide future efforts to develop therapeutic interventions that preserve respiratory function with neuromuscular injury/disease.

Reinnervation of the diaphragm by the inferior laryngeal nerve to the phrenic nerve in ventilator-dependent tetraplegic patients with C3-5 damage

The aim of this study was to evaluate the feasibility of unilateral diaphragmatic reinnervation in humans by the inferior laryngeal nerve. This pilot study included chronically ventilated tetraplegic patients with destruction of phrenic nerve motoneurons. Five patients were included. They all had a high level of tetraplegia, with phrenic nerve motor neuron destruction. They were highly dependent on ventilation, without any possibility of weaning. They did not have other chronic pathologies, especially laryngeal disease. They all had diaphragmatic explorations to diagnose the destruction of the motoneurons of the phrenic nerves and nasoendoscopy to be sure that they did not have laryngeal or pharyngeal disease. Then, surgical anastomosis of the right phrenic nerve was performed with the inferior laryngeal nerve, by a cervical approach. A laryngeal reinnervation was performed at the same time, using the ansa hypoglossi. One patient was excluded because of a functional phrenic nerve and one patient died 6 months after the surgery of a cardiac arrest. The remaining three patients were evaluated after the anastomosis every 6 months. They did not present any swallowing or vocal alterations. In these three patients, the diaphragmatic explorations showed that there was a recovery of the diaphragmatic electromyogram of the right and left hemidiaphragms after 1 year. Two patients had surgical diaphragmatic explorations for diaphragmatic pacing 18-24 months after the reinnervation with excellent results. At 36 months, none of the patients could restore their automatic ventilation. In conclusion, this study demonstrated that diaphragmatic reinnervation by the inferior laryngeal nerve is effective, without any vocal or swallowing complications.

Electrical Neuromodulation of the Respiratory System After Spinal Cord Injury

Spinal cord injury (SCI) is a complex and devastating condition characterized by disruption of descending, ascending, and intrinsic spinal circuitry resulting in chronic neurologic deficits. In addition to limb and trunk sensorimotor deficits, SCI can impair autonomic neurocircuitry such as the motor networks that support respiration and cough. High cervical SCI can cause complete respiratory paralysis, and even lower cervical or thoracic lesions commonly result in partial respiratory impairment. Although electrophrenic respiration can restore ventilator-independent breathing in select candidates, only a small subset of affected individuals can benefit from this technology at this moment. Over the past decades, spinal cord stimulation has shown promise for augmentation and recovery of neurologic function including motor control, cough, and breathing. The present review discusses the challenges and potentials of spinal cord stimulation for restoring respiratory function by overcoming some of the limitations of conventional respiratory functional electrical stimulation systems.

Long-term survival after traumatic spinal cord injury: a 70-year British study

STUDY DESIGN

Retrospective and prospective observational.

OBJECTIVES

Analyse long-term survival after traumatic spinal cord injury (SCI) in Great Britain over the 70-year study period, identify mortality risk factors and estimate current life expectancy.

SETTING

Two spinal centres in Great Britain.

METHODS

The sample consisted of patients with traumatic SCI injured 1943-2010 who survived the first year post-injury, had residual neurological deficit on discharge and were British residents. Life expectancy and trends over time were estimated by neurological grouping, age and gender, using logistic regression of person-years of follow-up combined with standard life table calculations.

RESULTS

For the 5483 cases of traumatic SCI the mean age at injury was 35.1 years, 79.7% were male, 31.1% had tetraplegia AIS/Frankel ABC, 41.2% paraplegia ABC,and 27.7% functionally incomplete lesion (all Ds). On 31 December 2014, 54% were still alive, 42.3% had died and 3.7% were lost to follow-up. Estimated life expectancies improved significantly between the 1950s and 1980s, plateaued during the next two decades, before slightly improving again since 2010. The estimated current life expectancy, compared with the general British population, ranged from 18.1 to 88.4% depending on the ventilator dependency, level and completeness of injury, age and gender.

CONCLUSIONS

Life expectancy after SCI improved significantly between the 1950s and 1980s, plateaued during the 1990s and 2000s, before slightly improving again since 2010, but still remains well below that of the general British population.

SPONSORSHIP

Buckinghamshire Healthcare NHS Trust Charitable Spinal Fund and Ann Masson Legacy for Spinal Research Fund, UK.

Nutritional status and metabolic profile in neurologically impaired pediatric surgical patients

BACKGROUND

Malnutrition is reported in pediatric neuromotor disability and impacts the child's health. We described the nutritional and metabolic status in neurologically impaired (NI) children undergoing surgery.

METHODS

Anthropometry, body composition, hormonal and nutritional evaluations were performed in 44 NI subjects (13.7±8.0 years). Energy needs were calculated by Krick's formula. Metabolic syndrome (MS) was defined applying the following criteria (≥3 defined MS): fasting blood glucose >100 mg/dL and/or homeostasis model assessment for insulin resistance (HOMA-IR) >97.5th percentile, trygliceride level >95th percentile, high-density lipoprotein (HDL)-cholesterol level <5th percentile, systolic/diastolic pressure >95th percentile; whilebody mass index - standard deviation score (BMI-SDS) <2 and biochemical malnutrition markers (≥2) defined undernutrition.

RESULTS

Energy intake was not adequate in 73.8% of the patients; no correlation between energy intake and BMI was noted. Undernutrition was noted in 34.1% of patients and MS in 11.36% of subjects. Fifty percent of the patients presented with insulin resistance, which was not related to BMI, body composition or other MS components.

CONCLUSIONS

Nutritional and metabolic monitoring of disabled children and young adults is recommended to prevent adverse outcomes associated with malnutrition.

Long-Term Mechanical Ventilation

Although precise numbers are difficult to obtain, the population of patients receiving long-term ventilation has increased over the last 20 years, and includes patients with chronic lung diseases, neuromuscular diseases, spinal cord injury, and children with complex disorders. This article reviews the equipment and logistics involved with ventilation outside of the hospital. Discussed are common locations for long-term ventilation, airway and secretion management, and many of the potential challenges faced by individuals on long-term ventilation.

Gene therapy and respiratory neuroplasticity

Breathing is a life-sustaining behavior that in mammals is accomplished by activation of dedicated muscles responsible for inspiratory and expiratory forces acting on the lung and chest wall. Motor control is exerted by specialized pools of motoneurons in the medulla and spinal cord innervated by projections from multiple centers primarily in the brainstem that act in concert to generate both the rhythm and pattern of ventilation. Perturbations that prevent the accomplishment of the full range of motor behaviors by respiratory muscles commonly result in significant morbidity and increased mortality. Recent developments in gene therapy and novel targeting strategies have contributed to deeper understanding of the organization of respiratory motor systems. Gene therapy has received widespread attention and substantial progress has been made in recent years with the advent of improved tools for vector design. Genes can be delivered via a variety of plasmids, synthetic or viral vectors and cell therapies. In recent years, adeno-associated viruses (AAV) have become one of the most commonly used vector systems, primarily because of the extensive characterization conducted to date and the versatility in targeting strategies. Recent studies highlight the power of using AAV to selectively and effectively transduce respiratory motoneurons and muscle fibers with promising therapeutic effects. This brief review summarizes current evidence for the use of gene therapy in respiratory disorders with a primary focus on interventions that address motor control and neuroplasticity, including regeneration, in the respiratory system.

Emergency Neurological Life Support: Traumatic Spine Injury

Traumatic spine injuries (TSIs) carry significantly high risks of morbidity, mortality, and exorbitant health care costs from associated medical needs following injury. For these reasons, TSI was chosen as an ENLS protocol. This article offers a comprehensive review on the management of spinal column injuries using the best available evidence. Alhough the review focuses primarily on cervical spinal column injuries, thoracolumbar injuries are briefly discussed as well. The initial emergency department clinical evaluation of possible spinal fractures and cord injuries, along with the definitive early management of confirmed injuries, is also covered.

No-fault compensation for ventilator-dependent children: a reasonable settlement value for lifetime attendant care

Severe neurological outcomes sustained in childhood often result in lifetime health care needs that are beyond the financial means of most families. When severe neurological deficits are alleged to have resulted from professional negligence, relief may be sought through litigation; however, the American tort system often yields inconsistent results or no compensation for patients. We sought to identify a reasonable, objective, and data-based monetary range for a no-fault compensation system with high- and low-financial limits for those with severe neurological deficits. Based on documented life expectancies and attendant care cost studies, the data analysis indicates a no-fault settlement payment ranging from US$479,712.24 to $3,098,504.16, reasonably ensures care and services for life.

Experimental Assessment and Future Applications of the Shikani Tracheostomy Speaking Valve

PURPOSE

Tracheostomy speaking valve use may increase airflow resistance and work of breathing. It remains unclear which valve offers the best performance characteristics. We compared the performance characteristics of the Shikani speaking valve (SSV; unidirectional-flow ball valve) with those of the Passy-Muir valve (PMV; bias-closed flapper valve).

METHOD

Airflow resistance was measured for both the SSV and the PMV at 8 flow amplitudes and in 3 orientations (-15°, 0°, +20°) in the bias-open and bias-closed configurations.

RESULTS

Significantly lower airflow resistance was observed for the SSV (bias open) compared with the PMV at -15° (p < .001), 0° (p < .001), and +20° (p = .006) from the horizon. No significant difference was observed between the PMV and the SSV (bias-closed) configuration at any of the tested angles. A nonsignificant trend toward decreased airflow resistance was observed between the SSV bias-open and bias-closed configurations at each of the angles tested.

CONCLUSIONS

The SSV demonstrated lower airflow resistance compared with the PMV across 8 flow amplitudes in the bias-open configuration at -15°, 0°, and +20° from the horizon. Further investigation is needed to determine the clinical impact of these findings on patient comfort, work of breathing, phonation, and airway protection during swallowing.

What are the perspectives for ventilated tetraplegics? A French retrospective study of 108 patients with cervical spinal cord injury

OBJECTIVE

Tetraplegic patients are often difficult to manage in intensive care units (ICU). The aim of our study was to calculate the incidence of patients in ICU with cervical spinal cord injury with special focus on tetraplegic patients on ventilation support and their future perspectives.

MATERIALS AND METHODS

This retrospective study included patients with cervical spinal cord injury in Upper Normandy, between 2002 and 2012. Data analyzed included age, sex, past medical history, date of onset of quadriplegia, level of neurological involvement, AIS grade, and ventilatory status.

RESULTS

One hundred and eight patients were included (49.0 ± 21.1 years). The most common etiology was fall (50 patients [46.3%]). Incidence was calculated at 12.7 per one million inhabitants. Tracheotomy was performed in 40.7% of patients. Long-term mechanical ventilation was required for 6.5%. At the end of the study, 9 patients (9.6%) were permanently hospitalized, 61 patients (64.9%) had returned home but none of the four ventilated patients had been discharged.

CONCLUSION

The conclusion of this work is that the future of highly tetraplegic patients is compromised, especially for those who remain reliant on mechanical ventilation.

Common mechanisms of compensatory respiratory plasticity in spinal neurological disorders

In many neurological disorders that disrupt spinal function and compromise breathing (e.g. ALS, cervical spinal injury, MS), patients often maintain ventilatory capacity well after the onset of severe CNS pathology. In progressive neurodegenerative diseases, patients ultimately reach a point where compensation is no longer possible, leading to catastrophic ventilatory failure. In this brief review, we consider evidence that common mechanisms of compensatory respiratory plasticity preserve breathing capacity in diverse clinical disorders, despite the onset of severe pathology (e.g. respiratory motor neuron denervation and/or death). We propose that a suite of mechanisms, operating at distinct sites in the respiratory control system, underlies compensatory respiratory plasticity, including: (1) increased (descending) central respiratory drive, (2) motor neuron plasticity, (3) plasticity at the neuromuscular junction or spared respiratory motor neurons, and (4) shifts in the balance from more to less severely compromised respiratory muscles. To establish this framework, we contrast three rodent models of neural dysfunction, each posing unique problems for the generation of adequate inspiratory motor output: (1) respiratory motor neuron death, (2) de- or dysmyelination of cervical spinal pathways, and (3) cervical spinal cord injury, a neuropathology with components of demyelination and motor neuron death. Through this contrast, we hope to understand the multilayered strategies used to "fight" for adequate breathing in the face of mounting pathology.

Life expectancy after spinal cord injury: a 50-year study

STUDY DESIGN

Cohort of incident cases from 1955 to 2006.

OBJECTIVES

To analyse acute and long-term mortality, estimate life expectancy and identify survival patterns of individuals experiencing traumatic spinal cord injury (SCI).

SETTING

Specialised SCI unit in Australia.

METHODS

Data for patients with traumatic SCI admitted to a spinal unit in Sydney, Australia between January 1955 and June 2006 were collated and deaths confirmed. Cumulative survival probability was estimated using life-table techniques and mortality rates were calculated from the number of deaths and aggregate years of exposure. Standardised mortality ratios (SMRs) were estimated from the ratio of observed to expected number of deaths. Life expectancy was then estimated using adjusted attained age-specific mortality rates.

RESULTS

From 2014 persons, 88 persons with tetraplegia (8.2%) and 38 persons with paraplegia (4.1%) died within 12 months of injury, most often with complete C1-4 tetraplegia. Among first-year survivors, overall 40-year survival rates were 47 and 62% for persons with tetraplegia and paraplegia, respectively. The most significant increases in mortality were seen in those with tetraplegia and American Spinal Injury Association Impairment Scale (AIS) grades A-C lesions, with SMRs between 5.4 and 9.0 for people <50 years, reducing with advancing attained age. Estimated life expectancies from 25 to 65 years ranged between 69-64%, 74-65%, 88-91% and 97-96% for C1-4 AIS A-C, C5-8 A-C, T1-S5 A-C and all AIS D lesions, respectively.

CONCLUSION

Survival related strongly to extent of neurological impairment. Future research should focus on identifying contextual factors, personal or environmental, that may contribute to the reduced life expectancy after SCI.

Phrenic motoneuron expression of serotonergic and glutamatergic receptors following upper cervical spinal cord injury

Following cervical spinal cord injury at C(2) (SH hemisection model) there is progressive recovery of phrenic activity. Neuroplasticity in the postsynaptic expression of neurotransmitter receptors may contribute to functional recovery. Phrenic motoneurons express multiple serotonergic (5-HTR) and glutamatergic (GluR) receptors, but the timing and possible role of these different neurotransmitter receptor subtypes in the neuroplasticity following SH are not clear. The current study was designed to test the hypothesis that there is an increased expression of serotonergic and glutamatergic neurotransmitter receptors within phrenic motoneurons after SH. In adult male rats, phrenic motoneurons were labeled retrogradely by intrapleural injection of Alexa 488-conjugated cholera toxin B. In thin (10μm) frozen sections of the spinal cord, fluorescently-labeled phrenic motoneurons were visualized for laser capture microdissection (LCM). Using quantitative real-time RT-PCR in LCM samples, the time course of changes in 5-HTR and GluR mRNA expression was determined in phrenic motoneurons up to 21 days post-SH. Expression of 5-HTR subtypes 1b, 2a and 2c and GluR subtypes AMPA, NMDA, mGluR1 and mGluR5 was evident in phrenic motoneurons from control and SH rats. Phrenic motoneuron expression of 5-HTR2a increased ~8-fold (relative to control) at 14 days post-SH, whereas NMDA expression increased ~16-fold by 21-days post-SH. There were no other significant changes in receptor expression at any time post-SH. This is the first study to systematically document changes in motoneuron expression of multiple neurotransmitter receptors involved in regulation of motoneuron excitability. By providing information on the neuroplasticity of receptors expressed in a motoneuron pool that is inactivated by a higher-level spinal cord injury, appropriate pharmacological targets can be identified to alter motoneuron excitability.

Home mechanical ventilation: a Canadian Thoracic Society clinical practice guideline

Increasing numbers of patients are surviving episodes of prolonged mechanical ventilation or benefitting from the recent availability of userfriendly noninvasive ventilators. Although many publications pertaining to specific aspects of home mechanical ventilation (HMV) exist, very few comprehensive guidelines that bring together all of the current literature on patients at risk for or using mechanical ventilatory support are available. The Canadian Thoracic Society HMV Guideline Committee has reviewed the available English literature on topics related to HMV in adults, and completed a detailed guideline that will help standardize and improve the assessment and management of individuals requiring noninvasive or invasive HMV. The guideline provides a disease-specific review of illnesses including amyotrophic lateral sclerosis, spinal cord injury, muscular dystrophies, myotonic dystrophy, kyphoscoliosis, post-polio syndrome, central hypoventilation syndrome, obesity hypoventilation syndrome, and chronic obstructive pulmonary disease as well as important common themes such as airway clearance and the process of transition to home. The guidelines have been extensively reviewed by international experts, allied health professionals and target audiences. They will be updated on a regular basis to incorporate any new information.

Mechanical ventilation, health, and quality of life following spinal cord injury

OBJECTIVE

To examine differences in perceived quality of life (QOL) at 1 year postinjury between people with tetraplegia who required mechanical ventilation assistance at discharge from rehabilitation and those who did not.

DESIGN

Prospective cross-sectional examination of people with spinal cord injury (SCI) drawn from the SCI Model Systems National Database.

SETTING

Community.

PARTICIPANTS

People with tetraplegia (N=1635) who sustained traumatic SCI between January 1, 1994, and September 30, 2008, who completed a 1-year follow-up interview, including 79 people who required at least some use of a ventilator at discharge from rehabilitation.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Satisfaction With Life Scale (SWLS); Craig Handicap Assessment and Reporting Technique (CHART)-Short Form Physical Independence, Mobility, Social Integration, and Occupation subscales; Patient Health Questionnaire-9 (PHQ-9), Medical Outcomes Study 36-Item Short-Form Health Survey self-perceived health status.

RESULTS

Significant differences were found between the ventilator-user (VU) group and non-ventilator-user (NVU) group for cause of trauma, proportion with complete injury, neurologic impairment level, and number of rehospitalizations. The NVU group had significantly higher SWLS and CHART Social Integration scores than the VU group after controlling for selected covariates. The NVU group also had more positive perceived health status compared with a year previously and a lower incidence of depression assessed by using the PHQ-9 than the VU group. There were no significant differences between groups for perceived current health status.

CONCLUSIONS

People in this study who did not require mechanical ventilation at discharge from rehabilitation post-SCI reported generally better health and improved QOL compared with those who required ventilator assistance at 1 year postinjury. Nonetheless, the literature suggests that perceptions of QOL improve as people live in the community for longer periods.

[Diaphragmatic pacemaker as an alternative to mechanical ventilation in patients with cervical spinal injury]

OBJECTIVE

To verify that the diaphragmatic pacemaker is a form of respiratory support that can be used to replace a volumetric respirator in cervical spinal injury patients with cervical spinal lesion and diaphragmatic paralysis by means of its comparison with the traditional volumetric respirator.

DESIGN

Retrospective study of a prospective database and age-matched case-control study.

SETTING

Intensive Care Unit and Intermediate Care Respiratory Unit, Paraplegics National Hospital, Toledo (Spain).

PATIENTS

We collected data on all patients discharged from the Hospital with permanent respiratory support by volumetric respirator or diaphragmatic pacemaker during a follow-up period of 25 years. Personal interviews were conducted to evaluate health-related quality of life. Comparison and survival tests were used for statistical comparisons.

INTERVENTIONS

Quality of life questionnaire.

MAIN VARIABLES

The main variables collected were demographic data, hospital stay, mortality, family reintegration and health-related quality of life.

RESULTS

We evaluated the clinical records of 101 patients, 37 in the pacemaker-group and 64 in the volumetric respirator-group. Our results show that ICU admission duration and hospitalization as well as family reintegration, without significant differences, with a tendency to greater survival in pacemaker patients (18.18 versus 9.67 years by the Kaplan-Meier method, p<0.001). However, this difference becomes non-significant (p=0.06) after adjustment of the groups by age. Furthermore, better quality of life was found in these same patients with pacemakers in terms of security, communication, sociability, comfort and mobility in the patients.

CONCLUSIONS

Diaphragmatic pacemaker ventilation is an effective alternative to mechanical ventilation with similar efficacy that improve quality of life in patients with severe respiratory failure due to cervical spinal cord injury.

Survival after short- or long-term ventilation after acute spinal cord injury: a single-centre 25-year retrospective study

STUDY DESIGN

A retrospective review of acute spinal cord injury patients having assisted ventilation on or after admission between 1981 and 2005.

OBJECTIVE

To assess survival after acute ventilatory support.

SETTING

Northwest Regional Spinal Injuries Centre, Southport, England.

METHODS

Causes of death were ascertained from the Office of National Statistics. Kaplan-Meier analysis of survival was calculated according to ventilator-wean status at discharge. Risk factors were obtained by Cox regression analysis.

RESULTS

Over 50% of deaths in weaned and ventilated patients were respiratory in origin. The mean survival of weaned patients in the age group 31-45 was 19.3 compared with 10.5 years for ventilated patients (P=0.047). Those under 30 survived a further 22.1 and 18.4 years (P=0.31), while those over 45 lived for 11.0 and 8.3 years (P=0.50), values for weaned and ventilated patients, respectively. The survival advantage for weaned patients in the middle age group was less evident when the 1-year survivors were compared. The mean survival time of younger patients with diaphragm pacing was 1.8 years longer than those on mechanical ventilation (P=0.142). The variables with significant hazard ratios were any comorbidity (3.07); mechanical ventilation on discharge (2.26); and older age at injury, (3.1).

CONCLUSIONS

The survival time for patients with high tetraplegia on long-term ventilation compares with other datasets and older patients have a proportionately greater loss in life expectancy. Self-ventilating patients with tetraplegia remain at considerable risk from respiratory death and consideration needs to be given to more effective preventative measures.

Risk and protective factors for mortality after spinal cord injury

Our purpose was to systematically review research on postacute risk and protective factors for mortality after spinal cord injury including psychological, environmental, behavioral and health factors. A theoretical risk model was used to identify these sets of predictive factors and to structure this article. The majority of research identifies basic demographic (age and race) and injury factors (severity). More limited research has indicated that personality, purpose in life, income, social support and negative risk behaviors predict mortality. In terms of health factors and secondary conditions, pressure ulcers, amputations, depressive diagnosis and need for treatment also predict mortality. Interventions are needed that diminish the risk of secondary conditions and early mortality.

Ventilator-associated pneumonia in long-term ventilator-assisted individuals

BACKGROUND

Information on the characteristics of pneumonia in long-term ventilator-assisted individuals is scarce. We evaluate the incidence, risk factors and outcome of ventilator-associated pneumonia (VAP) in a large series of chronically ventilated patients.

METHODS

All patients assisted in a chronic ventilator-dependent unit were prospectively followed up for the development of VAP. Patients with a new and persistent lung infiltrate and a purulent tracheal aspirate were suspected to have VAP. Pneumonia was considered microbiologically confirmed in the presence of (1) a positive blood culture and/or (2) ≥10⁵ CFU ml⁻¹ in quantitative bacterial culture of tracheal aspirates or ≥10³ CFU ml⁻¹ in quantitative mini-bronchoalveolar lavage cultures.

RESULTS

In total, 100 consecutive long-term ventilated individuals with spinal cord injury (mean age 49 years) were prospectively followed up. The length of mechanical ventilation before admission in the unit was 54±37 days, and the follow-up after admission was 119±127 days. There were 32 episodes of VAP in 27 patients (1.74 episodes per 1000 days of mechanical ventilation). By logistic regression analysis, hypoalbuminaemia (P=0.03), administration of antacids (P=0.002) and length of mechanical ventilation (P=0.05) were independent risk factors for VAP. The most frequently isolated organisms were Pseudomonas aeruginosa (62%), methicillin-resistant Staphylococcus aureus (25%) and Acinetobacter baumannii (15%); 9 (28%) episodes were polymicrobial. Antimicrobial treatment, including monotherapy in 66%, was successful in most patients. Only three patients (11%) died in relation to VAP.

CONCLUSIONS

Patients on long-term ventilation are at significant risk for the development of VAP, but the mortality is low.

A systematic review of intensive cardiopulmonary management after spinal cord injury

Intensive cardiopulmonary management is frequently undertaken in patients with spinal cord injury (SCI), particularly due to the occurrence of neurogenic shock and ventilatory insufficiency and in an attempt to reduce secondary injury. We undertook a systematic review of the literature to examine the evidence that intensive care management improves outcome after SCI and to attempt to define key parameters for cardiopulmonary support/resuscitation. We review the literature in five areas: management of SCI patients in specialized centers, risk in SCI patients of cardiopulmonary complications, parameters for blood pressure and oxygenation/ventilation support following SCI, risk factors for cardiopulmonary insufficiency requiring ICU care after SCI, and preventative strategies to reduce the risks of cardiopulmonary complications in SCI patients. The literature supports that, in light of the significant incidence of cardiorespiratory complications, SCI patients should be managed in a monitored special care unit. There is weak evidence supporting the maintenance of MAP >85 mmHg for a period extending up to 1 week following SCI.

Patients' characterization, hospital course and clinical outcomes in five Italian respiratory intensive care units

BACKGROUND

Respiratory intensive care units (RICU) dedicated to weaning could be suitable facilities for clinical management of "post-ICU" patients.

METHODS

We retrospectively analyzed the time course of patients' characteristics, clinical outcomes and medical staff utilization in five Italian RICUs by comparing three periods of 5 consecutive years (from 1991 to 2005).

RESULTS

A total of 3,106 patients (age 76 +/- 4 years; 72% males) were analyzed. The number of co-morbidities per patient (from 1.8 to 3.0, p = 0.05) and the previous intensive care unit (ICU) stay (from 25 to 32 days, p = 0.002) increased over time. The doctor-to-patient ratio significantly decreased over time (from 1:3 to 1:5, p < 0.01), whereas the physiotherapist-to-patient ratio mildly increased (from 1:6 to 1:4.5, p < 0.05). The overall weaning success rate decreased (from 87 to 66%, p < 0.001), and the discharge destination changed (p < 0.001) over time; fewer patients were discharged to home (from 22 to 10%), and more patients to nursing home (from 3 to 6%), acute hospitals (from 6 to 10%) and rehabilitative units (from 70 to 75%). The mortality rate increased over time (from 9 to 15%). Significant correlations between the doctor-to-patient ratio and the rates of weaning success (r = 0.679, p = 0.005), home discharge (r = 0.722, p = 0.002) and the RICU length of stay (LOS) (r = -0.683, p = 0.005) were observed.

CONCLUSIONS

The clinical outcomes of our units worsened over 15 years, likely as consequence of admitting more severely ill patients. The potential further negative influence of reduced medical staff availability on weaning success, home discharge and LOS warrants future prospective investigations.

Pulse wave velocity for assessment of arterial stiffness among people with spinal cord injury: a pilot study

BACKGROUND/OBJECTIVE

The most significant complication and leading cause of death for people with spinal cord injury (SCI) is coronary artery disease (CAD). It has been confirmed that aortic pulse wave velocity (PWV) is an emerging CAD predictor among able-bodied individuals. No prior study has described PWV values among people with SCI. The objective of this study was to compare aortic (the common carotid to femoral artery) PWV, arm (the brachial to radial artery) PWV, and leg (the femoral to posterior tibial artery) PWV in people with SCI (SCI group) to able-bodied controls (non-SCI group).

METHODS

Participants included 12 men with SCI and 9 non-SCI controls matched for age, sex, height, and weight. Participants with a history of CAD or current metabolic syndrome were excluded. Aortic, arm, and leg PWV was measured using the echo Doppler method.

RESULTS

Aortic PWV (mean +/- SD) in the SCI group (1,274 +/- 369 cm/s) was significantly higher (P < 0.05) than in the non-SCI group (948 +/- 110 cm/s). There were no significant between-group differences in mean arm PWV (SCI: 1,152 +/- 193 cm/s, non-SCI: 1,237 +/- 193 cm/s) or mean leg PWV (SCI: 1,096 +/- 173 cm/s, non-SCI: 994 +/- 178 cm/s) values.

CONCLUSIONS

Aortic PWV was higher among the SCI group compared with the non-SCI group. The higher mean aortic PWV values among the SCI group compared with the non-SCI group indicated a higher risk of CAD among people with SCI in the absence of metabolic syndrome.

Risk of stroke, heart attack, and diabetes complications among veterans with spinal cord injury

OBJECTIVES

To compare the rates of diabetes and macrovascular conditions in veterans with spinal cord injury (SCI) and to examine variations by patient-level demographic, socioeconomic, access, and health status factors.

DESIGN

A retrospective analysis. Diabetes status was classified by merging with diabetes epidemiology cohort using a validated algorithm. Chi-square tests and logistic regressions used to compare rates in macro- and microvascular conditions in veterans with and without diabetes.

SETTING

Veteran Health Administration clinic users in fiscal year (FY) 1999 to FY 2001.

PARTICIPANTS

SCI patients (N=8769) with diabetes (n=1333), in FY 2000, identified through the SCI registry.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Macrovascular and microvascular conditions in the next year (February 2001). Derived from International Statistical Classification of Diseases, 9th Revision, Clinical Modification, codes in the patient treatment files.

RESULTS

Overall, 15% of SCI veterans were identified with diabetes but this was an underestimate due to high mortality (8%). Among SCI veterans with diabetes, 49% had at least one macrovascular condition and 54% had microvascular conditions compared with 24% and 25% of those without diabetes (P<.001).

CONCLUSIONS

Our study highlights the highly significant relationship between diabetes and macro- and microvascular conditions in veterans with SCI. Neurologic deficit combined with increased insulin resistance has a greater macrovascular impact on SCI veterans than on those who do not have diabetes. Increasing age and physical comorbidities compound the problem.

A prospective study of health and risk of mortality after spinal cord injury

OBJECTIVE

To test hypothesized relationships between multiple health parameters and mortality among persons with spinal cord injury (SCI) while controlling for variations in biographical and injury characteristics.

DESIGN

Prospective cohort study with health data collected in late 1997 and early 1998 and mortality status ascertained in December 2005.

SETTING

A large rehabilitation hospital in the Southeastern United States.

PARTICIPANTS

A total of 1389 adults with traumatic SCI, at least 1 year postinjury.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The primary outcome was time from survey to mortality (or time of censoring). Mortality status was determined using the National Death Index and the Social Security Death Index. There were 225 deaths (16.2%) by December 31, 2005.

RESULTS

Cox proportional hazards modeling identified several significant health predictors of mortality status, while controlling for biographic and injury factors. Two sets of analyses were conducted--the first identifying the significance of a single variable of interest and the second analysis building a comprehensive model based on an optimal group of variables. Multiple types of health conditions were associated with mortality. The best set of health predictors included probable major depression, surgeries to repair pressure ulcers, fractures and/or amputations, symptoms of infections, and days hospitalized. Inclusion of these variables, along with a general health rating, improved prediction of survival compared with biographic and injury variables alone, because the pseudo R(2) increased from .12 to .18 and the concordance from .730 to .776.

CONCLUSIONS

In addition to secondary conditions that have been the traditional focus of prevention efforts (eg, pressure ulcers, urinary tract infections), amputations, fractures, and depressive symptoms were associated with higher risk for mortality; however, further research is needed to identify the association of specific conditions with causes of death and to determine whether interventions can modify these conditions and ultimately improve survival.

Mechanical ventilation or phrenic nerve stimulation for treatment of spinal cord injury-induced respiratory insufficiency

STUDY DESIGN

Prospective clinical study of two treatments.

OBJECTIVE

To compare mechanical ventilation (MV) with phrenic nerve stimulation (PNS) for treatment of respiratory device-dependent (RDD) spinal cord-injured (SCI) patients.

SETTING

Department for spinal cord-injured patients of an insurance-company-run trauma hospital in Hamburg, Germany.

METHODS

Prospective data collection of treatment-related data over 20 years.

RESULTS

In total, 64 SCI-RDD patients were treated during the study period. Of these, 32 of the patients with functioning phrenic nerves and diaphragm muscles were treated with PNS and 32 patients with destroyed phrenic nerves were mechanically ventilated. Incidence of respiratory infections (RIs per 100 days) prior to use of final respiratory device was equal in both groups, that is (median (interquartile range)) 1.43 (0.05-3.92) with PNS and 1.33 (0.89-2.21) with MV (P=0.888); with final device in our institution it was 0 (0-0.92) with PNS and 2.07 (1.49-4.19) with MV (P<0.001); at final location it was 0 (0-0.02) with PNS and 0.14 (0-0.31) with MV (P<0.001). Thus, compared to MV, respiratory treatment with PNS significantly reduces frequency of RI. Quality of speech is significantly better with PNS. Nine patients with PNS, but only two with MV, were employed or learned after rehabilitation (P=0.093). The primary investment in the respiratory device is higher with PNS, but it can be paid off in our setting within 1 year because of the reduced amount of single use equipment, easier nursing and fewer RIs compared to MV.

CONCLUSIONS

PNS instead of MV for treatment of SCI-RDD reduces RIs, running costs of respiratory treatment and obviously improves patients' quality of life.

Sir Ludwig Guttmann Lecture: Trends in spinal cord injury rehabilitation outcomes from model systems in the United States: 1973–2006

STUDY DESIGN

Consecutive case series with 5-year follow-up.

OBJECTIVE

To evaluate the spinal cord injury (SCI) model systems program in the United States by documenting improvements in treatment outcomes over time.

SETTING

SCI model systems throughout the United States.

METHODS

Initial data were collected on 24 332 patients injured between 1973 and 2006. Follow-up data were collected on 9225 of these patients 5 years post-injury. All data were grouped by calendar year. Descriptive statistics included means and percentages. Multiple linear or logistic regression was used to assess outcome trends after adjusting for demographics and injury severity.

RESULTS

Acute care and rehabilitation lengths of stay declined dramatically over time (P<0.01). Mean functional independence measure motor score at discharge and gain during rehabilitation decreased, whereas gain per day increased (P<0.01). The probability of neurologic improvement from admission to discharge increased. Odds of medical complications decreased during in-patient treatment, but increased post-discharge (P<0.05). Rehospitalizations declined over time (P<0.01). Community integration improved. First year mortality rates improved, but longer term mortality rates showed no improvement since 1982.

CONCLUSIONS

Steady improvements have occurred for many treatment outcomes. Newer and more effective methods of prevention and treatment need to be developed to target those outcomes that have not improved and remain suboptimal.

Survival in cerebral palsy in the last 20 years: signs of improvement?

This study investigated the possibility of improved survival in cerebral palsy (CP) over a 20-year period. Participants were 47 259 persons with CP receiving services from the State of California between 1983 and 2002. The person-year approach was used. This asks whether the probability of dying in a given calendar year changes over the study period after age and severity of disability are taken into account. An appreciable improvement over time was found in children with severe disabilities and in adults who required gastrostomy feeding. In these groups, mortality rates fell by 3.4% per year. Therefore, life expectancies reported in earlier studies should be increased by approximately 5 years if adjustments to 2002 mortality rates are made. For other persons with CP there was, at most, a small improvement over the 20-year period. The results suggest there have been improvements in the treatment and care of the most medically fragile children. Gastrostomy feeding has become much more widespread over the past two decades, and the improved survival of persons with gastrostomies may reflect better understanding of their requirements.