Discontinuous ventilator weaning of patients with acute SCI

Predicting extubation in patients with traumatic cervical spinal cord injury using the diaphragm electrical activity during a single maximal maneuver

BACKGROUND

The unsuccessful extubation in patients with traumatic cervical spinal cord injuries (CSCI) may result from impairment diaphragm function and monitoring of diaphragm electrical activity (EAdi) can be informative in guiding extubation. We aimed to evaluate whether the change of EAdi during a single maximal maneuver can predict extubation outcomes in CSCI patients.

METHODS

This is a retrospective study of CSCI patients requiring mechanical ventilation in the ICU of a tertiary hospital. A single maximal maneuver was performed by asking each patient to inhale with maximum strength during the first spontaneous breathing trial (SBT). The baseline (during SBT before maximal maneuver), maximum (during the single maximal maneuver), and the increase of EAdi (ΔEAdi, equal to the difference between baseline and maximal) were measured. The primary outcome was extubation success, defined as no reintubation after the first extubation and no tracheostomy before any extubation during the ICU stay.

RESULTS

Among 107 patients enrolled, 50 (46.7%) were extubated successfully at the first SBT. Baseline EAdi, maximum EAdi, and ΔEAdi were significantly higher, and the rapid shallow breathing index was lower in patients who were extubated successfully than in those who failed. By multivariable logistic analysis, ΔEAdi was independently associated with successful extubation (OR 2.03, 95% CI 1.52-3.17). ΔEAdi demonstrated high diagnostic accuracy in predicting extubation success with an AUROC 0.978 (95% CI 0.941-0.995), and the cut-off value was 7.0 μV.

CONCLUSIONS

The increase of EAdi from baseline SBT during a single maximal maneuver is associated with successful extubation and can help guide extubation in CSCI patients.

A Fast-Track Respiratory Protocol for High Cervical Spine Injury: A Case Report

BACKGROUND

Cervical spinal cord injury can greatly affect pulmonary function, resulting in complications, including respiratory failure with prolonged mechanical ventilation, ultimately leading to increased mortality and high health care costs. Weaning from mechanical ventilation is particularly challenging in patients with complete high spinal cord injury.

CASE PRESENTATION

We present the case of a 42-year-old man who suffered a complete cervical 5-6 spinal cord injury following a rollover motor vehicle crash and subsequently developed postoperative pneumonia and severe hypoxemic respiratory failure. He received a novel approach to fast-track respiratory care, including early and aggressive secretion clearance management, moderate pressure level of airway pressure release ventilation, timely transition to spontaneous mode, early tracheostomy and humane care, and high-flow oxygenation via tracheotomy after weaning off the ventilator. As a result, the patient experienced significant improvement in pulmonary function and was successfully liberated from the ventilator within a 2-week period.

CONCLUSION

This case highlights the potential effectiveness of fast-track respiratory care in promoting lung function restoration and expediting liberation from mechanical ventilation in patients with severe hypoxemic respiratory failure following a complete cervical spinal cord injury. However, further research is warranted to validate these findings and expand our understanding in this area.

Respiratory Complications and Weaning Considerations for Patients with Spinal Cord Injuries: A Narrative Review

Respiratory complications following traumatic spinal cord injury are common and are associated with high morbidity and mortality. The inability to cough and clear secretions coupled with weakened respiratory and abdominal muscles commonly leads to respiratory failure, pulmonary edema, and pneumonia. Higher level and severity of the spinal cord injury, history of underlying lung pathology, history of smoking, and poor baseline health status are potential predictors for patients that will experience respiratory complications. For patients who may require prolonged intubation, early tracheostomy has been shown to lead to improved outcomes. Prediction models to aid clinicians with the decision and timing of tracheostomy have been shown to be successful but require larger validation studies in the future. Mechanical ventilation weaning strategies also require further investigation but should focus on a combination of optimizing ventilator setting, pulmonary toilet techniques, psychosocial well-being, and an aggressive bowel regimen.

Comparison of Different Tidal Volumes for Ventilation in Patients with an Acute Traumatic Cervical Spine Injury

Background

There is scant literature comparing high tidal volume ventilation (HTV) over low tidal volume (LTV) ventilation in acute traumatic cervical spinal cord injury (CSCI).

Objective

The aim of this prospective randomized controlled parallel-group, single-blinded study was to compare the effect of two different tidal volumes (12-15 mL/kg and 6-8 mL/kg) in CSCI on days to achieve ventilator-free breathing (VFB), PaO2/FIO2 ratio, the incidence of complications, requirement of vasopressor drugs, total duration of hospital stay, and mortality.

Materials and Methods

We enrolled patients with acute high traumatic CSCI admitted to the neurotrauma intensive care unit within 24 h of injury, requiring mechanical ventilation. Participants were randomized to receive either HTV, 12-15 mL/kg (group H) or LTV, 6-8 mL/kg (group L) tidal volume ventilation.

Results and Conclusions

A total of 56 patients, 28 in each group were analyzed. Patient demographics and injury severity were comparable between the groups. VFB was achieved in 23 and 19 patients in groups H and L, respectively. The median number of days required to achieve VFB was 3 (2, 56) and 8 (2, 50) days, P = 0.33; PaO2: FIO2 ratio was 364.0 ± 64 and 321.0 ± 67.0, P = 0.01; the incidence of atelectasis was 25% and 46%, P = 0.16, respectively, in group H and group L. The hemodynamic parameters and the vasopressor requirement were comparable in both groups. There was no barotrauma. The duration of hospital stay (P = 0.2) and mortality (P = 0.2) was comparable in both groups. There was no significant difference in days to achieve ventilator-free breathing with HTV (12-15 mL/kg) ventilation compared to LTV (6-8 mL/kg) ventilation in acute CSCI. The PaO2:FiO2 ratio was higher with the use of 12-15 mL/kg. No difference in mortality and duration of hospital stay was seen in either group.

[Respiratory and physical recovery in cervical spinal cord injury. Seventeen years' experience in a weaning and rehabilitation center: An observational study]

INTRODUCTION AND OBJECTIVES

Spinal cord injury (SCI) is a devastating entity that generates substantial disability. The outcome of respiratory and motor features has an impact in human and social well-being. We analyzed demographic characteristics, motor and respiratory outcomes, and determined equipment needs at discharge in a weaning and rehabilitation center.

MATERIAL AND METHOD

Observational, descriptive and retrospective study of medical records between January 2002 and December 2018. Tracheostomised cervical SCI patients with invasive mechanical ventilation were included. Forced vital capacity (upright and supine), maximal inspiratory and expiratory pressures, ASIA and Spinal Cord Independence MeasureIII (SCIMIII) were obtained.

RESULTS

Of 1603 patients, 3.5% had SCI, and 28 met the inclusion criteria. The most frequent level of injury was C4-C5 (17/28), 21/28 had ASIAA classification, and 19 showed no change in either the ASIA or the SCIM score. In all, 22/28 patients were weaned, while 15/28 were decannulated. Twenty four patients were discharged to home. The most relevant change in SCIMIII was in the 5th component of respiration and sphincter subscale, related to weaning and tracheostomy. At discharge, 23/24 patients needed both respiratory and motor aids.

CONCLUSIONS

The admission rate of SCI patients was low in our weaning and rehabilitation center, with almost all being admitted for traumatic causes. Severity remained unchanged in most ASIAA patients. Respiratory recovery was more clinically significant than recovery of motor function. Upon discharge, most of our patients had to be equipped with both respiratory and motor aids.

Systematic Review of Incidence Studies of Pneumonia in Persons with Spinal Cord Injury

Pneumonia continues to complicate the course of spinal cord injury (SCI). Currently, clinicians and policy-makers are faced with only limited numbers of pneumonia incidence in the literature. A systematic review of the literature was undertaken to provide an objective synthesis of the evidence about the incidence of pneumonia in persons with SCI. Incidence was calculated per 100 person-days, and meta-regression was used to evaluate the influence of the clinical setting, the level of injury, the use of mechanical ventilation, the presence of tracheostomy, and dysphagia. For the meta-regression we included 19 studies. The incidence ranged from 0.03 to 7.21 patients with pneumonia per 100 days. The main finding of this review is that we found large heterogeneity in the reporting of the incidence, and we therefore should be cautious with interpreting the results. In the multivariable meta-regression, the incidence rate ratios showed very wide confidence intervals, which does not allow a clear conclusion concerning the risk of pneumonia in the different stages after a SCI. Large longitudinal studies with a standardized reporting on risk factors, pneumonia, and detailed time under observation are needed. Nevertheless, this review showed that pneumonia is still a clinically relevant complication and pneumonia prevention should focus on the ICU setting and patients with complete tetraplegia.

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).

Respiratory morbidity and mortality of traumatic cervical spinal cord injury at a level I trauma center in India

STUDY DESIGN

Descriptive retrospective.

OBJECTIVES

To evaluate the burden of respiratory morbidity in terms of ventilator dependence (VD) days and length of stay in neurotrauma ICU (NICU) and hospital, and to determine mortality in patients with traumatic cervical spinal cord injury (CSCI) in a low middle-income country (LMIC).

SETTING

Jai Prakash Narayan Apex Trauma Center (JPNATC), All India Institute of Medical Sciences (AIIMS), New Delhi, India.

METHODS

A total of 135 patients admitted with CSCI in the NICU between January 2017 to December 2018 were screened. Information regarding age, gender, American Spinal Injury Association (ASIA) impairment scale (AIS), level of injury, duration of VD, length of NICU, hospital stay, and outcome in terms of mortality or discharge from the hospital were obtained from the medical records.

RESULTS

A total of 106 CSCI patients were analyzed. The mean (SD) age of patients was 40 (±16) years and male: female ratio was 5:1. The duration of VD, duration of NICU, and hospital stay was a median of 8 days (IQR 1127), 6 days (IQR 1118), and 15 days (IQR 3127) respectively. Mortality was 19% (20/106). The mortality was significantly associated with poorer AIS score, VD, and duration of ICU and hospital stay. All patients were discharged to home only after they became ventilator-free.

CONCLUSIONS

The ventilator burden, hospital stay, and mortality are high in patients with CSCI in LMICs. Poor AIS scores, prolonged VD, ICU and hospital stay are associated with mortality. There is a need for comprehensive CSCI rehabilitation programs in LMICs to improve outcome.

Prolonged Weaning: S2k Guideline Published by the German Respiratory Society

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by respiratory muscle insufficiency and/or lung parenchymal disease; that is, when other treatments such as medication, oxygen administration, secretion management, continuous positive airway pressure (CPAP), or nasal high-flow therapy have failed. MV is required for maintaining gas exchange and allows more time to curatively treat the underlying cause of respiratory failure. In the majority of ventilated patients, liberation or "weaning" from MV is routine, without the occurrence of any major problems. However, approximately 20% of patients require ongoing MV, despite amelioration of the conditions that precipitated the need for it in the first place. Approximately 40-50% of the time spent on MV is required to liberate the patient from the ventilator, a process called "weaning". In addition to acute respiratory failure, numerous factors can influence the duration and success rate of the weaning process; these include age, comorbidities, and conditions and complications acquired during the ICU stay. According to international consensus, "prolonged weaning" is defined as the weaning process in patients who have failed at least 3 weaning attempts, or require more than 7 days of weaning after the first spontaneous breathing trial (SBT). Given that prolonged weaning is a complex process, an interdisciplinary approach is essential for it to be successful. In specialised weaning centres, approximately 50% of patients with initial weaning failure can be liberated from MV after prolonged weaning. However, the heterogeneity of patients undergoing prolonged weaning precludes the direct comparison of individual centres. Patients with persistent weaning failure either die during the weaning process, or are discharged back to their home or to a long-term care facility with ongoing MV. Urged by the growing importance of prolonged weaning, this Sk2 Guideline was first published in 2014 as an initiative of the German Respiratory Society (DGP), in conjunction with other scientific societies involved in prolonged weaning. The emergence of new research, clinical study findings and registry data, as well as the accumulation of experience in daily practice, have made the revision of this guideline necessary. The following topics are dealt with in the present guideline: Definitions, epidemiology, weaning categories, underlying pathophysiology, prevention of prolonged weaning, treatment strategies in prolonged weaning, the weaning unit, discharge from hospital on MV, and recommendations for end-of-life decisions. Special emphasis was placed on the following themes: (1) A new classification of patient sub-groups in prolonged weaning. (2) Important aspects of pulmonary rehabilitation and neurorehabilitation in prolonged weaning. (3) Infrastructure and process organisation in the care of patients in prolonged weaning based on a continuous treatment concept. (4) Changes in therapeutic goals and communication with relatives. Aspects of paediatric weaning are addressed separately within individual chapters. The main aim of the revised guideline was to summarize both current evidence and expert-based knowledge on the topic of "prolonged weaning", and to use this information as a foundation for formulating recommendations related to "prolonged weaning", not only in acute medicine but also in the field of chronic intensive care medicine. The following professionals served as important addressees for this guideline: intensivists, pulmonary medicine specialists, anaesthesiologists, internists, cardiologists, surgeons, neurologists, paediatricians, geriatricians, palliative care clinicians, rehabilitation physicians, intensive/chronic care nurses, physiotherapists, respiratory therapists, speech therapists, medical service of health insurance, and associated ventilator manufacturers.