High tidal volume ventilation is associated with ventilator-associated pneumonia in acute cervical spinal cord injury

Progress in the relationship between mechanical ventilation parameters and ventilator-related complications during perioperative anesthesia

BACKGROUND

Mechanical ventilation, as an important respiratory support, plays an important role in general anesthesia and it is the cornerstone of intraoperative management of surgical patients. Different from spontaneous respiration, intraoperative mechanical ventilation can lead to postoperative lung injury, and its impact on surgical mortality cannot be ignored. Postoperative lung injury increases hospital stay and is related to preoperative conditions, anesthesia time, and intraoperative ventilation settings.

METHOD

Through reading literature and research reports, the relationship between perioperative input parameters and output parameters related to mechanical ventilation and ventilator-related complications was reviewed, providing reference for the subsequent setting of input parameters of mechanical ventilation and new ventilation strategies.

RESULTS

The parameters of inspiratory pressure rise time and inspiratory time can change the gas distribution, gas flow rate and airway pressure into the lungs, but there are few clinical studies on them. It can be used as a prospective intervention to study the effect of specific protective ventilation strategies on pulmonary complications after perioperative anesthesia.

CONCLUSION

There are many factors affecting lung function after perioperative mechanical ventilation. Due to the difference of human body, the ventilation parameters suitable for each patient are different, and the deviation of each ventilation parameter can lead to postoperative pulmonary complications. Inspiratory pressure rise time and inspiratory time will be used as the new ventilation strategy.

High vs. low tidal volume and pulmonary complications in patients with cervical spinal cord injury on mechanical ventilation: systematic review

Introduction

Cervical spinal cord injury (CSCI) patients on mechanical ventilation often lack standardized guidelines for optimal ventilatory support. This study reviews existing literature to compare outcomes between high tidal volume (HTV) and low tidal volume (LTV) strategies in this unique patient population.

Methods

We searched for studies published up to August 30, 2023, in five databases, following a PECO/PICO strategy. We found six studies for quantitative analysis and meta-analyzed five studies.

Results

This meta-analysis included 396 patients with CSCI and mechanical ventilation (MV), 119 patients treated with high tidal volume (HTV), and 277 with low tidal volume (LTV). This first meta-analysis incorporates the few studies that show contradictory findings. Our meta-analysis shows that there is no significant statistical difference in developing VAP between both comparison groups (HTV vs. LTV) (OR 0.46; 95% CI 0.13 to 1.66; p > 0.05; I2: 0%), nor are there differences between the presence of other pulmonary complications when treating with HTV such as acute respiratory distress syndrome (ARDS), atelectasis, onset of weaning.

Conclusion

In patients with CSCI in MV, the use of HTV does not carry a greater risk of pneumonia compared to LTV; in turn, it is shown as a safe ventilatory strategy as it does not establish an increase in other pulmonary complications such as ARDS, atelectasis, the onset of weaning nor others associated with volutrauma. It is necessary to evaluate the role of HTV ventilation in this group of patients in primary RCT-type studies.

Ventilatory Strategies in Traumatic Cervical Spinal Cord Injury: Controversies and Current Updates

Ventilatory management of patients with traumatic cervical spinal cord injury (CSCI) is a complex and controversial area of critical care medicine. Despite significant advances in our understanding of the pathophysiology of CSCI and the development of novel interventions, there remains a lack of consensus about the optimal approach to ventilatory management in these patients. Some of the key controversies in CSCI ventilatory management include timing of tracheal intubation, non-invasive ventilation versus invasive ventilation, high versus low tidal volume, and early versus late tracheostomy. The objective of this review is to discuss the existing controversies and provide an insight on the current evidence.

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.

Dysphagia is associated with worse clinical outcomes in geriatric trauma patients

Introduction

Dysphagia is associated with increased morbidity, mortality, and resource utilization in hospitalized patients, but studies on outcomes in geriatric trauma patients with dysphagia are limited. We hypothesized that geriatric trauma patients with dysphagia would have worse clinical outcomes compared with those without dysphagia.

Methods

Patients with and without dysphagia were compared in a single-center retrospective cohort study of trauma patients aged ≥65 years admitted in 2019. The primary outcome was mortality. Secondary outcomes included intensive care unit (ICU) length of stay (LOS), hospital LOS, discharge destination, and unplanned ICU admission. Multivariable regression analyses and Bayesian analyses adjusted for age, Injury Severity Score, mechanism of injury, and gender were performed to determine the association between dysphagia and clinical outcomes.

Results

Of 1706 geriatric patients, 69 patients (4%) were diagnosed with dysphagia. Patients with dysphagia were older with a higher Injury Severity Score. Increased odds of mortality did not reach statistical significance (OR 1.6, 95% CI 0.6 to 3.4, p=0.30). Dysphagia was associated with increased odds of unplanned ICU admission (OR 4.6, 95% CI 2.0 to 9.6, p≤0.001) and non-home discharge (OR 5.2, 95% CI 2.4 to 13.9, p≤0.001), as well as increased ICU LOS (OR 4.9, 95% CI 3.1 to 8.1, p≤0.001), and hospital LOS (OR 2.1, 95% CI 1.7 to 2.6, p≤0.001). On Bayesian analysis, dysphagia was associated with an increased probability of longer hospital and ICU LOS, unplanned ICU admission, and non-home discharge.

Conclusions

Clinically apparent dysphagia is associated with poor outcomes, but it remains unclear if dysphagia represents a modifiable risk factor or a marker of underlying frailty, leading to poor outcomes. This study highlights the importance of screening protocols for dysphagia in geriatric trauma patients to possibly mitigate adverse outcomes.

Level of evidence

Level III.

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.

Established and Emerging Therapies in Acute Spinal Cord Injury

Acute spinal cord injury (SCI) is devastating for patients and their caretakers and has an annual incidence of 20–50 per million people. Following initial assessment with appropriate physical examination and imaging, patients who are deemed surgical candidates should undergo decompression with stabilization. Earlier intervention can improve neurological recovery in the post-operative period while allowing earlier mobilization. Optimized medical management is paramount to improve outcomes. Emerging strategies for managing SCI in the acute period stem from an evolving understanding of the pathophysiology of the injury. General areas of focus include ischemia prevention, reduction of secondary injury due to inflammation, modulation of the cytotoxic and immune response, and promotion of cellular regeneration. In this article, we review established, emerging, and novel experimental therapies. Continued translational research on these methods will improve the feasibility of bench-to-bedside innovations in treating patients with acute SCI.

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.