Management and outcome of mechanically ventilated neurologic patients. Crit Care Med. 2011;39:1482-1492. [PMID: 21378554 DOI: 10.1097/ccm.0b013e31821209a8]

Long-term survival of traumatic brain injury and intra-cerebral haemorrhage patients: A multicentric observational cohort

PURPOSE

Mortality is often assessed during ICU stay and early after, but rarely at later stage. We aimed to compare the long-term mortality between TBI and ICH patients.

MATERIALS AND METHODS

From an observational cohort, we studied 580 TBI patients and 435 ICH patients, admitted from January 2013 to February 2021 in 3 ICUs and alive at 7-days post-ICU discharge. We performed a Lasso-penalized Cox survival analysis.

RESULTS

We estimated 7-year survival rates at 72.8% (95%CI from 67.3% to 78.7%) for ICH patients and at 84.9% (95%CI from 80.9% to 89.1%) for TBI patients: ICH patients presenting a higher mortality risk than TBI patients. Additionally, we identified variables associated with higher mortality risk (age, ICU length of stay, tracheostomy, low GCS, absence of intracranial pressure monitoring). We also observed anisocoria related with the mortality risk in the early stage after ICU stay.

CONCLUSIONS

In this ICU survivor population with a prolonged follow-up, we highlight an acute risk of death after ICU stay, which seems to last longer in ICH patients. Several variables characteristic of disease severity appeared associated with long-term mortality, raising the hypothesis that the most severe patients deserve closer follow-up after ICU stay.

The impact of comorbidities on prolonged mechanical ventilation in patients with chronic obstructive pulmonary disease

BACKGROUND

In patients with chronic obstructive pulmonary disease (COPD) and acute respiratory failure, approximately 10% of them are considered to be at high risk for prolonged mechanical ventilation (PMV, > 21 days). PMV have been identified as independent predictors of unfavorable outcomes. Our previous study revealed that patients aged 70 years older and COPD severity were at a significantly higher risk for PMV. We aimed to analyze the impact of comorbidities and their associated risks in patients with COPD who require PMV.

METHODS

The data used in this study was collected from Kaohsiung Medical University Hospital Research Database. The COPD subjects were the patients first diagnosed COPD (index date) between January 1, 2012 and December 31, 2020. The exclusion criteria were the patients with age less than 40 years, PMV before the index date or incomplete records. COPD and non-COPD patients, matched controls were used by applying the propensity score matching method.

RESULTS

There are 3,744 eligible patients with COPD in the study group. The study group had a rate of 1.6% (60 cases) patients with PMV. The adjusted HR of PMV was 2.21 (95% CI 1.44-3.40; P < 0.001) in the COPD patients than in non-COPD patients. Increased risks of PMV were found significantly for patients with diabetes mellitus (aHR 4.66; P < 0.001), hypertension (aHR 3.20; P = 0.004), dyslipidemia (aHR 3.02; P = 0.015), congestive heart failure (aHR 6.44; P < 0.001), coronary artery disease (aHR 3.11; P = 0.014), stroke (aHR 6.37; P < 0.001), chronic kidney disease (aHR 5.81 P < 0.001) and Dementia (aHR 5.78; P < 0.001).

CONCLUSIONS

Age, gender, and comorbidities were identified as significantly higher risk factors for PMV occurrence in the COPD patients compared to the non-COPD patients. Beyond age, comorbidities also play a crucial role in PMV in COPD.

Mortality, Functional Status, and Quality of Life after 5 Years of Patients Admitted to Critical Care for Spontaneous Intracerebral Hemorrhage

BACKGROUND

The objective of this study was to assess long-term outcome in patients with spontaneous intracerebral hemorrhage admitted to the intensive care unit.

METHODS

Mortality and Glasgow Outcome Scale, Barthel Index, and 5-level EQ-5D version (EQ-5D-5L) scores were analyzed in a multicenter cohort study of three Spanish hospitals (336 patients). Mortality was also analyzed in the Medical Information Mart for Intensive Care III (MIMIC-III) database.

RESULTS

The median (25th percentile-75th percentile) age was 62 (50-70) years, the median Glasgow Coma Score was 7 (4-11) points, and the median Acute Physiology and Chronic Health disease Classification System II (APACHE-II) score was 21 (15-26) points. Hospital mortality was 54.17%, mortality at 90 days was 56%, mortality at 1 year was 59.2%, and mortality at 5 years was 66.4%. In the Glasgow Outcome Scale, a normal or disabled self-sufficient situation was recorded in 21.5% of patients at 6 months, in 25.5% of patients after 1 year, and in 22.1% of patients after 5 years of follow-up (4.5% missing). The Barthel Index score of survivors improved over time: 50 (25-80) points at 6 months, 70 (35-95) points at 1 year, and 90 (40-100) points at 5 years (p < 0.001). Quality of life evaluated with the EQ-5D-5L at 1 year and 5 years indicated that greater than 50% of patients had no problems or slight problems in all items (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression). In the MIMIC-III study (N = 1354), hospital mortality was 31.83% and was 40.5% at 90 days and 56.2% after 5 years.

CONCLUSIONS

In patients admitted to the intensive care unit with a diagnosis of nontraumatic intracerebral hemorrhage, hospital mortality up to 90 days after admission is very high. Between 90 days and 5 years after admission, mortality is not high. A large percentage of survivors presented a significant deficit in quality of life and functional status, although with progressive improvement over time. Five years after the hemorrhagic stroke, a survival of 30% was observed, with a good functional status seen in 20% of patients who had been admitted to the hospital.

Acute Respiratory Failure in Severe Acute Brain Injury

Acute respiratory failure is commonly encountered in severe acute brain injury due to a multitude of factors related to the sequelae of the primary injury. The interaction between pulmonary and neurologic systems in this population is complex, often with competing priorities. Many treatment modalities for acute respiratory failure can result in deleterious effects on cerebral physiology, and secondary brain injury due to elevations in intracranial pressure or impaired cerebral perfusion. High-quality literature is lacking to guide clinical decision-making in this population, and deliberate considerations of individual patient factors must be considered to optimize each patient's care.

Immune regulation of the gut-brain axis and lung-brain axis involved in ischemic stroke

Local ischemia often causes a series of inflammatory reactions when both brain immune cells and the peripheral immune response are activated. In the human body, the gut and lung are regarded as the key reactional targets that are initiated by brain ischemic attacks. Mucosal microorganisms play an important role in immune regulation and metabolism and affect blood-brain barrier permeability. In addition to the relationship between peripheral organs and central areas and the intestine and lung also interact among each other. Here, we review the molecular and cellular immune mechanisms involved in the pathways of inflammation across the gut-brain axis and lung-brain axis. We found that abnormal intestinal flora, the intestinal microenvironment, lung infection, chronic diseases, and mechanical ventilation can worsen the outcome of ischemic stroke. This review also introduces the influence of the brain on the gut and lungs after stroke, highlighting the bidirectional feedback effect among the gut, lungs, and brain.

Incidence and Outcomes of Acute Respiratory Distress Syndrome in Brain-Injured Patients Receiving Invasive Ventilation: A Secondary Analysis of the ENIO Study

Background: Acute respiratory distress syndrome (ARDS) is an important pulmonary complication in brain-injured patients receiving invasive mechanical ventilation (IMV). We aimed to evaluate the incidence and association between ARDS and clinical outcomes in patients with different forms of acute brain injury requiring IMV in the intensive care unit (ICU). Methods: This was a preplanned secondary analysis of a prospective, multicenter, international cohort study (NCT03400904). We included brain-injured patients receiving IMV for ≥ 24 h. ARDS was the main exposure of interest and was identified during index ICU admission using the Berlin definition. We examined the incidence and adjusted association of ARDS with ICU mortality, ICU length of stay, duration of IMV, and extubation failure. Outcomes were evaluated using mixed-effect logistic regression and cause-specific Cox proportional hazards models. Results: 1492 patients from 67 hospitals and 16 countries were included in the analysis, of whom 137 individuals developed ARDS (9.2% of overall cohort). Across countries, the median ARDS incidence was 5.1% (interquartile range [IQR] 0-10; range 0-27.3). ARDS was associated with increased ICU mortality (adjusted odds ratio (OR) 2.66; 95% confidence interval [CI], 1.29-5.48), longer ICU length of stay (adjusted hazard ratio [HR] 0.59; 95% CI, 0.48-0.73), and longer duration of IMV (adjusted HR 0.54; 95% CI, 0.44-0.67). The association between ARDS and extubation failure approached statistical significance (adjusted HR 1.48; 95% CI 0.99-2.21). Higher ARDS severity was associated with incrementally longer ICU length of stay and longer cumulative duration of IMV. Findings remained robust in a sensitivity analysis evaluating the magnitude of unmeasured confounding. Conclusions: In this cohort of acutely brain-injured patients, the incidence of ARDS was similar to that reported in other mixed cohorts of critically ill patients. Development of ARDS was associated with worse outcomes.

Surgical Versus Dilational Tracheostomy in Patients with Severe Stroke: A SETPOINT2 Post hoc Analysis

BACKGROUND

Tracheostomy in mechanically ventilated patients with severe stroke can be performed surgically or dilationally. Prospective data comparing both methods in patients with stroke are scarce. The randomized Stroke-Related Early Tracheostomy vs Prolonged Orotracheal Intubation in Neurocritical Care Trial2 (SETPOINT2) assigned 382 mechanically ventilated patients with stroke to early tracheostomy versus extubation or standard tracheostomy. Surgical tracheostomy (ST) was performed in 41 of 307 SETPOINT2 patients, and the majority received dilational tracheostomy (DT). We aimed to compare ST and DT in these patients with patients.

METHODS

All SETPOINT2 patients with ST were compared with a control group of patients with stroke undergoing DT (1:2), selected by propensity score matching that included the factors stroke type, SETPOINT2 randomization group, Stroke Early Tracheostomy score, patient age, and premorbid functional status. Successful decannulation was the primary outcome, and secondary outcome parameters included functional outcome at 6 months and adverse events attributable to tracheostomy. Potential predictors of decannulation were evaluated by regression analysis.

RESULTS

Baseline characteristics were comparable in the two groups of patients with stroke undergoing ST (n = 41) and matched patients with stroke undergoing DT (n = 82). Tracheostomy was performed significantly later in the ST group than in the DT group (median 9 [interquartile range {IQR} 5-12] vs. 9 [IQR 4-11] days after intubation, p = 0.025). Patients with ST were mechanically ventilated longer (median 19 [IQR 17-24] vs.14 [IQR 11-19] days, p = 0.008) and stayed in the intensive care unit longer (median 23 [IQR 16-27] vs. 17 [IQR 13-24] days, p = 0.047), compared with patients with DT. The intrahospital infection rate was significantly higher in the ST group compared to the DT group (14.6% vs. 1.2%, p = 0.002). At 6 months, decannulation rates (56% vs. 61%), functional outcomes, and mortality were not different. However, decannulation was performed later in the ST group compared to the DT group (median 81 [IQR 66-149] vs. 58 [IQR 32-77] days, p = 0.004). Higher baseline Stroke Early Tracheostomy score negatively predicted decannulation.

CONCLUSIONS

In ventilated patients with severe stroke in need of tracheostomy, surgical and dilational methods are associated with comparable decannulation rate and functional outcome at 6 months. However, ST was associated with longer time to decannulation and higher rates of early infections, supporting the dilational approach to tracheostomy in ventilated patients with stroke.

Weaning and extubation failure in myasthenic crisis: a multicenter analysis

Myasthenic crisis (MC) requiring mechanical ventilation is a serious complication of myasthenia gravis (MG). Here we analyze the frequency and risk factors of weaning- and extubation failure as well as its impact on the clinical course in a large cohort. We performed a retrospective chart review on patients treated for MC in 12 German neurological departments between 2006 and 2015. Weaning failure (WF) was defined as negative spontaneous breathing trial, primary tracheostomy, or extubation failure (EF) (reintubation or death). WF occurred in 138 episodes (64.2%). Older Age (p = 0.039), multiple comorbidities (≥ 3) (p = 0.007, OR = 4.04), late-onset MG (p = 0.004, OR = 2.84), complications like atelectasis (p = 0.008, OR = 3.40), pneumonia (p < 0.0001, OR = 3.45), cardio-pulmonary resuscitation (p = 0.005, OR = 5.00) and sepsis (p = 0.02, OR = 2.57) were associated with WF. WF occurred often in patients treated with intravenous immungloblins (IVIG) (p = 0.002, OR = 2.53), whereas WF was less often under first-line therapy with plasma exchange or immunoadsorption (p = 0.07, OR = 0.57). EF was observed in 58 of 135 episodes (43.0%) after first extubation attempt and was related with prolonged mechanical ventilation, intensive care unit stay and hospital stay (p ≤ 0.0001 for all). Extubation success was most likely in a time window for extubation between day 7 and 12 after intubation (p = 0.06, OR = 2.12). We conclude that WF and EF occur very often in MC and are associated with poor outcome. Older age, multiple comorbidities and development of cardiac and pulmonary complications are associated with a higher risk of WF and EF. Our data suggest that WF occurs less frequently under first-line plasma exchange/immunoadsorption compared with first-line use of IVIG.

Development of a Prediction Score for Evaluation of Extubation Readiness in Neurosurgical Patients with Mechanical Ventilation

BACKGROUND

There is no widely accepted consensus on the weaning and extubating protocols for neurosurgical patients, leading to heterogeneity in clinical practices and high rates of delayed extubation and extubation failure-related health complications.

METHODS

In this single-center prospective observational diagnostic study, mechanically ventilated neurosurgical patients with extubation attempts were consecutively enrolled for 1 yr. Responsive physicians were surveyed for the reasons for delayed extubation and developed the Swallowing, Tongue protrusion, Airway protection reflected by spontaneous and suctioning cough, and Glasgow Coma Scale Evaluation (STAGE) score to predict the extubation success for neurosurgical patients already meeting other general extubation criteria.

RESULTS

A total of 3,171 patients were screened consecutively, and 226 patients were enrolled in this study. The rates of delayed extubation and extubation failure were 25% (57 of 226) and 19% (43 of 226), respectively. The most common reasons for the extubation delay were weak airway-protecting function and poor consciousness. The area under the receiver operating characteristics curve of the total STAGE score associated with extubation success was 0.72 (95% CI, 0.64 to 0.79). Guided by the highest Youden index, the cutoff point for the STAGE score was set at 6 with 59% (95% CI, 51 to 66%) sensitivity, 74% (95% CI, 59 to 86%) specificity, 90% (95% CI, 84 to 95%) positive predictive value, and 30% (95% CI, 21 to 39%) negative predictive value. At STAGE scores of 9 or higher, the model exhibited a 100% (95% CI, 90 to 100%) specificity and 100% (95% CI, 72 to 100%) positive predictive value for predicting extubation success.

CONCLUSIONS

After a survey of the reasons for delayed extubation, the STAGE scoring system was developed to better predict the extubation success rate. This scoring system has promising potential in predicting extubation readiness and may help clinicians avoid delayed extubation and failed extubation-related health complications in neurosurgical patients.

EDITOR’S PERSPECTIVE

The effect of age on clinical outcomes in critically ill brain-injured patients

PURPOSE

We studied the impact of age on survival and functional recovery in brain-injured patients.

METHODS

We performed an observational cohort study of all consecutive adult patients with brain injury admitted to ICU in 8 years. To estimate the optimal cut-off point of the age associated with unfavorable outcomes (mRS 3-6), receiver operating characteristic (ROC) curve analyses were used. Multivariate logistic regression analyses were performed to identify prognostic factors for unfavorable outcomes.

RESULTS

We included 619 brain-injured patients. We identified 60 years as the cut-off point at which the probability of unfavorable outcomes increases. Patients ≥ 60 years had higher severity scores at ICU admission, longer duration of mechanical ventilation, longer ICU and hospital stays, and higher mortality. Factors identified as associated with unfavorable outcomes (mRS 3-6) were an advanced age (≥ 60 years) [Odds ratio (OR) 4.59, 95% confidence interval (CI) 2.73-7.74, p < 0.001], a low GCS score (≤ 8 points) [OR 3.72, 95% CI 1.95-7.08, p < 0.001], the development of intracranial hypertension [OR 5.52, 95% CI 2.70-11.28, p < 0.001], and intracerebral hemorrhage as the cause of neurologic disease [OR 3.87, 95% CI 2.34-6.42, p < 0.001].

CONCLUSION

Mortality and unfavorable functional outcomes in critically ill brain-injured patients were associated with older age (≥ 60 years), higher clinical severity (determined by a lower GCS score at admission and the development of intracranial hypertension), and an intracerebral hemorrhage as the cause of neurologic disease.

Distribution of bacteria and risk factors in patients with multidrug-resistant pneumonia in a single center rehabilitation ward

Stroke patients may have dysphagia and frequent aspiration increasing exposure to antibiotics and the chance of multidrug-resistant (MDR) bacteria infection. This study investigated clinical risk factors and related antibiotic use of MDR bacteria infection in stroke patients in the rehabilitation ward, hoping that it can help prevent and reduce the condition of MDR bacteria. A retrospective cohort study was conducted using the database of stroke patients with pneumonia admitted to the rehabilitation ward from January 1, 2020, to June 30, 2022. The selected stroke patients were divided into the MDR and non-MDR groups. Analyze the infection bacteria of the 2 groups. Forward logistic regression was applied to identify possible independent MDR bacteria infection risk factors. A total of 323 patients were included. The top 3 common MDR pathogens were Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Almost all Pseudomonas aeruginosa and Acinetobacter baumannii are resistant to ertapenem. National Institute of Health stroke scale at admission was associated with MDR bacteria infection pneumonia (OR [odds ratio] = 1.078, 95%CI [1.017, 1.142]). Long-term tracheotomy (OR = 2.695, 95%CI [1.232, 5.897]), hypoalbuminemia (OR = 473, 95%CI [1.318, 4.642]), and bilateral cerebral hemisphere stroke (OR = 4.021, 95%CI [2.009, 8.048]) were significant clinical risk factors of MDR pneumonia after stroke. The detection rate of MDR bacteria has increased. Understanding the distribution and drug resistance of MDR bacteria in stroke patients with pneumonia in the neurological rehabilitation ward and the related susceptibility of MDR bacteria infection is necessary. This way, the treatment plan can be adjusted more timely, avoiding the abuse of antibiotics.

Development of a core outcome set for ventilation trials in neurocritical care patients with acute brain injury: protocol for a Delphi consensus study of international stakeholders

INTRODUCTION

There is little consensus and high heterogeneity on the optimal set of relevant clinical outcomes in research studies regarding extubation in neurocritical care patients with brain injury undergoing mechanical ventilation. The aims of this study are to: (1) develop a core outcome set (COS) and (2) reach consensus on a hierarchical composite endpoint for such studies.

METHODS AND ANALYSIS

The study will include a broadly representative, international panel of stakeholders with research and clinical expertise in this field and will involve four stages: (1) a scoping review to generate an initial list of outcomes represented in the literature, (2) an investigator meeting to review the outcomes for inclusion in the Delphi surveys, (3) four rounds of online Delphi consensus-building surveys and (4) online consensus meetings to finalise the COS and hierarchical composite endpoint.

ETHICS AND DISSEMINATION

This study received ethical approval from the French Society of Anesthesia and Critical Care Medicine Institutional Review Board (SFAR CERAR-IRB 00010254-2023-029). The study results will be disseminated through communication to stakeholders, publication in a peer-reviewed journal, and presentations at conferences.

TRIAL REGISTRATION NUMBER

This study is registered with the Core Outcome Measures in Effectiveness Trials (COMET) Initiative.

Implementation and impact of a point of care electroencephalography platform in a community hospital: a cohort study

Objective

To determine the clinical and financial feasibility of implementing a poc-EEG system in a community hospital.

Design

Data from a prospective cohort displaying abnormal mentation concerning for NCSE or rhythmic movements due to potential underlying seizure necessitating EEG was collected and compared to a control group containing patient data from 2020.

Setting

A teaching community hospital with limited EEG support.

Patients

The study group consisted of patients requiring emergent EEG during hours when conventional EEG was unavailable. Control group is made up of patients who were emergently transferred for EEG during the historical period.

Interventions

Application and interpretation of Ceribell®, a poc-EEG system.

Measurement and main results

88 patients were eligible with indications for poc-EEG including hyperkinetic movements post-cardiac arrest (19%), abnormal mentation after possible seizure (46%), and unresponsive patients with concern for NCSE (35%). 21% had seizure burden on poc-EEG and 4.5% had seizure activity on follow-up EEG. A mean of 1.1 patients per month required transfer to a tertiary care center for continuous EEG. For the control period, a total of 22 patients or a mean of 2 patients per month were transferred for emergent EEG. Annually, we observed a decrease in the number of transferred patients in the post-implementation period by 10.8 (95% CI: -2.17-23.64, p = 0.1). Financial analysis of the control found the hospital system incurred a loss of $3,463.11 per patient transferred for an annual loss of $83,114.64. In the study group, this would compute to an annual loss of $45,713.05 for an overall decrease in amount lost of $37,401.59. We compared amount lost per patient between historical controls and study patients. Implementation of poc-EEG resulted in an overall decrease in annual amount lost of $37,401.59 by avoidance of transfer fees. We calculated the amount gained per patient in the study group to be $13,936.44. To cover the cost of the poc-EEG system, 8.59 patients would need to avoid transfer annually.

Conclusion

A poc-EEG system can be safely implemented in a community hospital leading to an absolute decrease in transfers to tertiary hospital. This decrease in patient transfers can cover the cost of implementing the poc-EEG system. The additional benefits from transfer avoidance include clinical benefits such as rapid appropriate treatment of seizures and avoidance of unnecessary treatment as well as negating transfer risk and keeping the patient at their local hospital.

Effect of mechanical insufflation-exsufflation for ineffective cough on weaning duration in diseases of the peripheral or central nervous system (MEDINE): study protocol for a randomised controlled trial in a neurological weaning centre

INTRODUCTION

Patients with neurological or neurosurgical disease can suffer from impaired cough, which may result in life-threatening retention of tracheobronchial secretions, atelectasis, pneumonia and finally death. Due to a lack of alternatives and pathophysiological plausibility, the application of mechanical insufflation-exsufflation (MI-E) has already become international standard care in neuromuscular disease and spinal cord injury although a lack of evidence for efficacy. High-quality studies to support the use of MI-E in neurological and neurosurgical patients during weaning from mechanical ventilation are missing. The goal of this exploratory study is to display the effect size of MI-E intervention on the duration of mechanical ventilation and additional outcomes.

METHODS AND ANALYSIS

One hundred adult patients with a cough deficiency or retention of secretion admitted to a neurological intensive care unit (ICU) are planned to be recruited for this randomised controlled trial. Patients are randomised 1:1 to receive either MI-E or best standard care. Observation will take place until discharge from the hospital, death or end of the study period. The primary endpoint of this trial is the duration of mechanical ventilation from randomisation until successful weaning. The outcome will be analysed with Kaplan-Meier estimation and competing risks analyses. Secondary endpoint is the proportion of patients with successful weaning. Further outcomes will include the incidence of hospital-acquired pneumonia, mortality, decannulation rate, length of stay on the ICU and the total score of the Glasgow Coma Scale.

ETHICS AND DISSEMINATION

The study was approved by the Medical Ethics Committee of the University of Oldenburg. The findings of this study will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

DRKS00020981.

Respiratory challenges and ventilatory management in different types of acute brain-injured patients

Acute brain injury (ABI) covers various clinical entities that may require invasive mechanical ventilation (MV) in the intensive care unit (ICU). The goal of MV, which is to protect the lung and the brain from further injury, may be difficult to achieve in the most severe forms of lung or brain injury. This narrative review aims to address the respiratory issues and ventilator management, specific to ABI patients in the ICU.

Preoperative systemic immune-inflammation index may predict prolonged mechanical ventilation in patients with spontaneous basal ganglia intracerebral hemorrhage undergoing surgical operation

Background

Prolonged mechanical ventilation (PMV) has been proven as a risk factor for poor prognosis in patients with neurocritical illness. Spontaneous basal ganglia intracerebral hemorrhage (ICH) is one common subtype of hemorrhagic stroke and is associated with high morbidity and mortality. The systemic immune-inflammation index (SII) is used as a novel and valuable prognostic marker for various neoplastic diseases and other critical illnesses.

Objective

This study aimed to analyze the predictive value of preoperative SII for PMV in patients with spontaneous basal ganglia ICH who underwent surgical operations.

Methods

This retrospective study was conducted in patients with spontaneous basal ganglia ICH who underwent surgical operations between October 2014 and June 2021. SII was calculated using the following formula: SII = platelet count × neutrophil count/lymphocyte count. Multivariate logistic regression analysis and receiver operating characteristics curve (ROC) were used to evaluate the potential risk factors of PMV after spontaneous basal ganglia ICH.

Results

A total of 271 patients were enrolled. Of these, 112 patients (47.6%) presented with PMV. Multivariate logistic regression analysis showed that preoperative GCS (OR, 0.780; 95% CI, 0.688-0.883; P < 0.001), hematoma size (OR, 1.031; 95% CI, 1.016-1.047; P < 0.001), lactic acid (OR, 1.431; 95% CI, 1.015-2.017; P = 0.041) and SII (OR, 1.283; 95% CI, 1.049-1.568; P = 0.015) were significant risk factors for PMV. The area under the ROC curve (AUC) of SII was 0.662 (95% CI, 0.595-0.729, P < 0.001), with a cutoff value was 2,454.51.

Conclusion

Preoperative SII may predict PMV in patients with spontaneous basal ganglia ICH undergoing a surgical operation.

Serum LDH levels may predict poor neurological outcome after aneurysmal subarachnoid hemorrhage

INTRODUCTION

Serum lactate dehydrogenase (LDH) levels are often elevated in cardiovascular diseases. Their prognostic role after subarachnoid hemorrhage (SAH) remains poorly evaluated.

METHODS

This is a retrospective single-center study of patients with non-traumatic SAH admitted to the intensive care unit (ICU) of an University Hospital from 2007 to 2022. Exclusion criteria were pregnancy and incomplete medical records or follow-up data. Baseline information, clinical data, radiologic data, the occurrence of neurological complications as well as serum LDH levels during the first 14 days of ICU stay were collected. Unfavorable neurological outcome (UO) at 3 months was defined as a Glasgow Outcome Scale of 1-3.

RESULTS

Five hundred and forty-seven patients were included; median serum LDH values on admission and the highest LDH values during the ICU stay were 192 [160-230] IU/L and 263 [202-351] IU/L, respectively. The highest LDH value was recorded after a median of 4 [2-10] days after ICU admission. LDH levels on admission were significantly higher in patients with UO. When compared with patients with favorable outcome (FO), patients with UO had higher serum LDH values over time. In the multivariate logistic regression model, the highest LDH value over the ICU stay (OR 1.004 [95% CI 1.002 - 1.006]) was independently associated with the occurrence of UO; the area under the receiving operator (AUROC) curve for the highest LDH value over the ICU stay showed a moderate accuracy to predict UO (AUC 0.76 [95% CI 0.72-0.80]; p < 0.001), with an optimal threshold of > 272 IU/L (69% sensitivity and 74% specificity).

CONCLUSIONS

The results in this study suggest that high serum LDH levels are associated with the occurrence of UO in SAH patients. As a readily and available biomarker, serum LDH levels should be evaluated to help with the prognostication of SAH patients.

Mechanical ventilation in patients with acute brain injury: a systematic review with meta-analysis

OBJECTIVE

To describe the potential effects of ventilatory strategies on the outcome of acute brain-injured patients undergoing invasive mechanical ventilation.

DESIGN

Systematic review with an individual data meta-analysis.

SETTING

Observational and interventional (before/after) studies published up to August 22nd, 2022, were considered for inclusion. We investigated the effects of low tidal volume Vt < 8 ml/Kg of IBW versus Vt >  = 8 ml/Kg of IBW, positive end-expiratory pressure (PEEP) < or >  = 5 cmH2O and protective ventilation (association of both) on relevant clinical outcomes.

POPULATION

Patients with acute brain injury (trauma or haemorrhagic stroke) with invasive mechanical ventilation for ≥ 24 h.

MAIN OUTCOME MEASURES

The primary outcome was mortality at 28 days or in-hospital mortality. Secondary outcomes were the incidence of acute respiratory distress syndrome (ARDS), the duration of mechanical ventilation and the partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FiO2) ratio.

RESULTS

The meta-analysis included eight studies with a total of 5639 patients. There was no difference in mortality between low and high tidal volume [Odds Ratio, OR 0.88 (95%Confidence Interval, CI 0.74 to 1.05), p = 0.16, I2 = 20%], low and moderate to high PEEP [OR 0.8 (95% CI 0.59 to 1.07), p = 0.13, I2 = 80%] or protective and non-protective ventilation [OR 1.03 (95% CI 0.93 to 1.15), p = 0.6, I2 = 11]. Low tidal volume [OR 0.74 (95% CI 0.45 to 1.21, p = 0.23, I2 = 88%], moderate PEEP [OR 0.98 (95% CI 0.76 to 1.26), p = 0.9, I2 = 21%] or protective ventilation [OR 1.22 (95% CI 0.94 to 1.58), p = 0.13, I2 = 22%] did not affect the incidence of acute respiratory distress syndrome. Protective ventilation improved the PaO2/FiO2 ratio in the first five days of mechanical ventilation (p < 0.01).

CONCLUSIONS

Low tidal volume, moderate to high PEEP, or protective ventilation were not associated with mortality and lower incidence of ARDS in patients with acute brain injury undergoing invasive mechanical ventilation. However, protective ventilation improved oxygenation and could be safely considered in this setting. The exact role of ventilatory management on the outcome of patients with a severe brain injury needs to be more accurately delineated.

Ventilator-associated pneumonia in neurocritically ill patients: insights from the ENIO international prospective observational study

BACKGROUND

Acute brain injured (ABI) patients are at high risk of developing ventilator-associated pneumonia (VAP). However, incidence, risk factors and effects on outcome of VAP are not completely elucidated in this population. The primary aim of this study was to determine the incidence of VAP in a cohort of ABI patients. The secondary objectives included the identification of risk factors for development of VAP, and the impact of VAP on clinical outcomes. Clinical outcomes were defined as intensive care unit length of stay (ICU-LOS), duration of invasive mechanical ventilation (IMV), and ICU mortality.

METHODS

Pre-planned sub-analysis of the Extubation strategies in Neuro-Intensive care unit (ICU) patients and associations with Outcomes (ENIO) international multi-center prospective observational study. Patients with available data on VAP, who received at least 48 h of IMV and ICU-LOS ≥ 72 h were included.

RESULTS

Out of 1512 patients included in the ENIO study, 1285 were eligible for this analysis. The prevalence of VAP was 39.5% (33.7 cases /1000 ventilator-days), with a high heterogeneity across countries and according to the type of brain injury. VAP was significantly more frequent in male patients, in those with smoke habits and when intraparenchymal probe (IP), external ventricular drain (EVD) or hypothermia (p < 0.001) were used. Independent risk factors for VAP occurrence were male gender, the use of IP, hypothermia, and the occurrence of tracheobronchitis during ICU stay. VAP was not an independent risk factor for ICU mortality (Hazard Ratio, HR = 0.71 95%CI 0.43-1.16, p = 0.168), but was independently associated with longer ICU stay (OR = 2.55 95%CI 2.01-3.23, p < 0.001).

CONCLUSIONS

VAP is common in ABI patients. Male gender, IP and EVD insertion, tracheobronchitis, and the use of therapeutic hypothermia were significantly associated with VAP occurrence. VAP did not affect mortality but increased ICU-LOS.

Lung infection by Pseudomonas aeruginosa induces neuroinflammation and blood-brain barrier dysfunction in mice

BACKGROUND

Severe lung infection can lead to brain dysfunction and neurobehavioral disorders. The mechanisms that regulate the lung-brain axis of inflammatory response to respiratory infection are incompletely understood. This study examined the effects of lung infection causing systemic and neuroinflammation as a potential mechanism contributing to blood-brain barrier (BBB) leakage and behavioral impairment.

METHODS

Lung infection in mice was induced by instilling Pseudomonas aeruginosa (PA) intratracheally. We determined bacterial colonization in tissue, microvascular leakage, expression of cytokines and leukocyte infiltration into the brain.

RESULTS

Lung infection caused alveolar-capillary barrier injury as indicated by leakage of plasma proteins across pulmonary microvessels and histopathological characteristics of pulmonary edema (alveolar wall thickening, microvessel congestion, and neutrophil infiltration). PA also caused significant BBB dysfunction characterized by leakage of different sized molecules across cerebral microvessels and a decreased expression of cell-cell junctions (VE-cadherin, claudin-5) in the brain. BBB leakage peaked at 24 h and lasted for 7 days post-inoculation. Additionally, mice with lung infection displayed hyperlocomotion and anxiety-like behaviors. To test whether cerebral dysfunction was caused by PA directly or indirectly, we measured bacterial load in multiple organs. While PA loads were detected in the lungs up to 7 days post-inoculation, bacteria were not detected in the brain as evidenced by negative cerebral spinal fluid (CSF) cultures and lack of distribution in different brain regions or isolated cerebral microvessels. However, mice with PA lung infection demonstrated increased mRNA expression in the brain of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), chemokines (CXCL-1, CXCL-2) and adhesion molecules (VCAM-1 and ICAM-1) along with CD11b + CD45+ cell recruitment, corresponding to their increased blood levels of white cells (polymorphonuclear cells) and cytokines. To confirm the direct effect of cytokines on endothelial permeability, we measured cell-cell adhesive barrier resistance and junction morphology in mouse brain microvascular endothelial cell monolayers, where administration of IL-1β induced a significant reduction of barrier function coupled with tight junction (TJ) and adherens junction (AJ) diffusion and disorganization. Combined treatment with IL-1β and TNFα augmented the barrier injury.

CONCLUSIONS

Lung bacterial infection is associated with BBB disruption and behavioral changes, which are mediated by systemic cytokine release.

Mechanical hyperinflation maneuver and intracranial compliance of critical neurological patients: protocol for a randomized controlled equivalence trial

BACKGROUND

Mechanical hyperinflation maneuver (MHM) is a technique known for optimizing bronchial hygiene and respiratory mechanics; however, its effects on intracranial compliance are not known.

METHODS

Sixty patients aged ≥ 18 years, with clinical diagnosis of acute stroke, confirmed by neuroimaging examination, with onset of symptoms within 72 h, under mechanical ventilation through tracheal tube, will participate in this study. Participants will be randomly allocated into 2 groups: experimental group (n = 30)-MHM plus tracheal aspiration-and control group (n = 30)-tracheal aspiration only. Intracranial compliance will be measured by a non-invasive technique using Brain4care BcMM-R-2000 sensor. This will be the primary outcome. Results will be recorded at 5 times: T0 (start of monitoring), T1 (moment before MHM), T2 (moment after the MHM and before tracheal aspiration), T3 (moment after tracheal aspiration), T4, and T5 (monitoring 10 and 20 min after T3). Secondary outcomes are respiratory mechanics and hemodynamic parameters.

DISCUSSION

This study will be the first clinical trial to examine the effects and safety of MHM on intracranial compliance measured by non-invasive monitoring. Limitation includes the impossibility of blinding the physical therapist who will supervise the interventions. It is expected with this study to demonstrate that MHM can improve respiratory mechanics and hemodynamic parameters and provide a safe intervention with no changes in intracranial compliance in stroke patients.

Tracheostomy timing and outcome in critically ill patients with stroke: a meta-analysis and meta-regression

BACKGROUND

Stroke patients requiring mechanical ventilation often have a poor prognosis. The optimal timing of tracheostomy and its impact on mortality in stroke patients remains uncertain. We performed a systematic review and meta-analysis of tracheostomy timing and its association with reported all-cause overall mortality. Secondary outcomes were the effect of tracheostomy timing on neurological outcome (modified Rankin Scale, mRS), hospital length of stay (LOS), and intensive care unit (ICU) LOS.

METHODS

We searched 5 databases for entries related to acute stroke and tracheostomy from inception to 25 November 2022. We adhered to PRISMA guidance for reporting systematic reviews and meta-analyses. Selected studies included (1) ICU-admitted patients who had stroke (either acute ischaemic stroke, AIS or intracerebral haemorrhage, ICH) and received a tracheostomy (with known timing) during their stay and (2) > 20 tracheotomised. Studies primarily reporting sub-arachnoid haemorrhage (SAH) were excluded. Where this was not possible, adjusted meta-analysis and meta-regression with study-level moderators were performed. Tracheostomy timing was analysed continuously and categorically, where early (< 5 days from initiation of mechanical ventilation to tracheostomy) and late (> 10 days) timing was defined per the protocol of SETPOINT2, the largest and most recent randomised controlled trial on tracheostomy timing in stroke patients.

RESULTS

Thirteen studies involving 17,346 patients (mean age = 59.8 years, female 44%) met the inclusion criteria. ICH, AIS, and SAH comprised 83%, 12%, and 5% of known strokes, respectively. The mean time to tracheostomy was 9.7 days. Overall reported all-cause mortality (adjusted for follow-up) was 15.7%. One in five patients had good neurological outcome (mRS 0-3; median follow-up duration was 180 days). Overall, patients were ventilated for approximately 12 days and had an ICU LOS of 16 days and a hospital LOS of 28 days. A meta-regression analysis using tracheostomy time as a continuous variable showed no statistically significant association between tracheostomy timing and mortality (β = - 0.3, 95% CI = - 2.3 to 1.74, p = 0.8). Early tracheostomy conferred no mortality benefit when compared to late tracheostomy (7.8% vs. 16.4%, p = 0.7). Tracheostomy timing was not associated with secondary outcomes (good neurological outcome, ICU LOS and hospital LOS).

CONCLUSIONS

In this meta-analysis of over 17,000 critically ill stroke patients, the timing of tracheostomy was not associated with mortality, neurological outcomes, or ICU/hospital LOS.

TRIAL REGISTRATION

PROSPERO-CRD42022351732 registered on 17th of August 2022.

Prognostic Factors Associated With Extubation Failure in Acutely Brain-Injured Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

Extubation failure in brain-injured patients is associated with increased morbidity. Our objective was to systematically review prognostic factors associated with extubation failure in acutely brain-injured adult patients receiving invasive ventilation in an ICU.

DATA SOURCES

MEDLINE, Embase, and Cochrane Central were searched from inception to January 31, 2022.

STUDY SELECTION

Two reviewers independently screened citations and selected English-language cohort studies and randomized trials examining the association of prognostic factors with extubation failure. Studies were considered if they included greater than or equal to 80% adult patients with acute brain injury admitted to the ICU and mechanically ventilated for greater than or equal to 24 hours.

DATA EXTRACTION

Two reviewers extracted data on population, prognostic factors, extubation outcomes, and risk of bias (using the quality in prognostic factors tool).

DATA SYNTHESIS

In the primary analysis, adjusted odds ratios (aOR) for each prognostic factor were pooled using random-effects models. Certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation. The search identified 7,626 citations, of which 21 studies met selection criteria. Moderate-certainty evidence suggested increased risk of extubation failure with older age (aOR, 3.0 for upper vs lower tertile; 95% CI, 1.78-5.07) and longer duration of mechanical ventilation (aOR, 3.47 for upper vs lower tertile; 95% CI, 1.68-7.19). Presence of cough (aOR, 0.40; 95% CI, 0.28-0.57) and intact swallow (aOR, 0.34; 95% CI, 0.21-0.54) probably decreased risk of extubation failure (moderate certainty). Associations of other factors with extubation failure were informed by low or very low certainty evidence.

CONCLUSIONS

Patient age, duration of mechanical ventilation, and airway reflexes were associated with extubation failure in brain-injured patients with moderate certainty. Future studies are needed to determine the optimal application of these variables in clinical practice.

Liberation from Mechanical Ventilation and Tracheostomy Practice in Traumatic Brain Injury

Liberating patients with severe traumatic brain injury (TBI) from mechanical ventilation is often a challenging task. These patients frequently require prolonged ventilation and have persistent alterations in the level and content of consciousness. Questions about their ability to protect their airway are common. Pulmonary complications and copious respiratory secretions are also very prevalent. Thus, it is hardly surprising that rates of extubation failure are high. This is a major problem because extubation failure is associated with a host of poor outcome measures. When the safety of an extubation attempt is uncertain, direct tracheostomy is favored by some, but there is no evidence that this practice leads to better outcomes. Current knowledge is insufficient to reliably predict extubation outcomes in TBI, and practices vary substantially across trauma centers. Yet observational studies provide relevant information that must be weighted when considering the decision to attempt extubation in patients with head injury. This review discusses available evidence on liberation from mechanical ventilation in TBI, proposes priorities for future research, and offers practical advice to guide decisions at the bedside.

Mechanical Ventilation in Patients with Traumatic Brain Injury: Is it so Different?

Patients with traumatic brain injury (TBI) frequently require invasive mechanical ventilation and admission to an intensive care unit. Ventilation of patients with TBI poses unique clinical challenges, and careful attention is required to ensure that the ventilatory strategy (including selection of appropriate tidal volume, plateau pressure, and positive end-expiratory pressure) does not cause significant additional injury to the brain and lungs. Selection of ventilatory targets may be guided by principles of lung protection but with careful attention to relevant intracranial effects. In patients with TBI and concomitant acute respiratory distress syndrome (ARDS), adjunctive strategies include sedation optimization, neuromuscular blockade, recruitment maneuvers, prone positioning, and extracorporeal life support. However, these approaches have been largely extrapolated from studies in patients with ARDS and without brain injury, with limited data in patients with TBI. This narrative review will summarize the existing evidence for mechanical ventilation in patients with TBI. Relevant literature in patients with ARDS will be summarized, and where available, direct data in the TBI population will be reviewed. Next, practical strategies to optimize the delivery of mechanical ventilation and determine readiness for extubation will be reviewed. Finally, future directions for research in this evolving clinical domain will be presented, with considerations for the design of studies to address relevant knowledge gaps.

Lung infection by P. aeruginosa induces neuroinflammation and blood-brain barrier dysfunction in mice

Background Severe lung infection can lead to brain dysfunction and neurobehavioral disorders. The mechanisms that regulate the lung-brain axis of inflammatory response to respiratory infection are incompletely understood. This study examined the effects of lung infection causing systemic and neuroinflammation as a potential mechanism contributing to blood-brain barrier (BBB) leakage and behavioral impairment. Methods Pneumonia was induced in adult C57BL/6 mice by intratracheal inoculation of Pseudomonas aeruginosa (PA). Solute extravasation, histology, immunofluorescence, RT-PCR, multiphoton imaging and neurological testing were performed in this study. Results Lung infection caused alveolar-capillary barrier injury as indicated by leakage of plasma proteins across pulmonary microvessels and histopathological characteristics of pulmonary edema (alveolar wall thickening, microvessel congestion, and neutrophil infiltration). PA also caused significant BBB dysfunction characterized by leakage of different sized molecules across cerebral microvessels and a decreased expression of cell-cell junctions (VE-cadherin, claudin-5) in the brain. BBB leakage peaked at 24 hours and lasted for 7 days post-inoculation. Additionally, mice with lung infection displayed hyperlocomotion and anxiety-like behaviors. To test whether cerebral dysfunction was caused by PA directly or indirectly, we measured bacterial load in multiple organs. While PA loads were detected in the lungs up to 7 days post-inoculation, bacteria were not detected in the brain as evidenced by negative cerebral spinal fluid (CSF) cultures and lack of distribution in different brain regions or isolated cerebral microvessels. However, mice with PA lung infection demonstrated increased mRNA expression in the brain of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), chemokines (CXCL-1, CXCL-2) and adhesion molecules (VCAM-1 and ICAM-1) along with CD11b + cell recruitment, corresponding to their increased blood levels of white cells (polymorphonuclear cells) and cytokines. To confirm the direct effect of cytokines on endothelial permeability, we measured cell-cell adhesive barrier resistance and junction morphology in mouse brain microvascular endothelial cell monolayers, where administration of IL-1β induced a significant reduction of barrier function coupled with tight junction (TJ) diffusion and disorganization. Combined treatment with IL-1β and TNFα augmented the barrier injury. Conclusions These results suggest that lung bacterial infection causes cerebral microvascular leakage and neuroinflammation via a mechanism involving cytokine-induced BBB injury.

Lung infection by P. aeruginosa induces neuroinflammation and blood-brain barrier dysfunction in mice

Background

Severe lung infection can lead to brain dysfunction and neurobehavioral disorders. The mechanisms that regulate the lung-brain axis of inflammatory response to respiratory infection are incompletely understood. This study examined the effects of lung infection causing systemic and neuroinflammation as a potential mechanism contributing to blood-brain barrier (BBB) leakage and behavioral impairment.

Methods

Pneumonia was induced in adult C57BL/6 mice by intratracheal inoculation of Pseudomonas aeruginosa (PA). Solute extravasation, histology, immunofluorescence, RT-PCR, multiphoton imaging and neurological testing were performed in this study.

Results

Lung infection caused alveolar-capillary barrier injury as indicated by leakage of plasma proteins across pulmonary microvessels and histopathological characteristics of pulmonary edema (alveolar wall thickening, microvessel congestion, and neutrophil infiltration). PA also caused significant BBB dysfunction characterized by leakage of different sized molecules across cerebral microvessels and a decreased expression of cell-cell junctions (VE-cadherin, claudin-5) in the brain. BBB leakage peaked at 24 hours and lasted for 7 days post-inoculation. Additionally, mice with lung infection displayed hyperlocomotion and anxiety-like behaviors. To test whether cerebral dysfunction was caused by PA directly or indirectly, we measured bacterial load in multiple organs. While PA loads were detected in the lungs up to 7 days post-inoculation, bacteria were not detected in the brain as evidenced by negative cerebral spinal fluid (CSF) cultures and lack of distribution in different brain regions or isolated cerebral microvessels. However, mice with PA lung infection demonstrated increased mRNA expression in the brain of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), chemokines (CXCL-1, CXCL-2) and adhesion molecules (VCAM-1 and ICAM-1) along with CD11b+ cell recruitment, corresponding to their increased blood levels of white cells (polymorphonuclear cells) and cytokines. To confirm the direct effect of cytokines on endothelial permeability, we measured cell-cell adhesive barrier resistance and junction morphology in mouse brain microvascular endothelial cell monolayers, where administration of IL-1β induced a significant reduction of barrier function coupled with tight junction (TJ) diffusion and disorganization. Combined treatment with IL-1β and TNFα augmented the barrier injury.

Conclusions

These results suggest that lung bacterial infection causes cerebral microvascular leakage and neuroinflammation via a mechanism involving cytokine-induced BBB injury.

The mechanical power in neurocritical care patients: is it useful?

Patients with acute brain injury have been excluded in the majority of the randomized clinical trials which evaluated a lung protective strategy in patients with acute respiratory failure. It remains unclear if low tidal volume, higher PEEP levels and recruitment maneuvers by increasing both the intracranial and intrathoracic pressure and by leading to a permissible hypercapnia could furthermore deteriorate the acute brain injury and the final outcome. Mechanical power has been associated with the outcome in ARDS patients without brain injury. Jiang et al. demonstrated in neurocritical patients that non-survivors had a higher mechanical power compared to survivors. Mechanical power was associated with an increase in intensive care mortality risk and also to an enhanced risk of hospital mortality, prolonged intensive care length of stay and fewer ventilatory free days; in addition, the mechanical power could better predict mortality compared to the Glasgow Coma Scale.

Mechanical power of ventilation is associated with mortality in neurocritical patients: a cohort study

This study aimed to determine the predictive relevance of mechanical power in the clinical outcomes (such as ICU mortality, hospital mortality, 90-day mortality, length of ICU stay, and number of ventilator-free days at day 28) of neurocritical patients. This is a retrospective cohort analysis of an open-access clinical database known as MIMIC-III. The study included patients who had sustained an acute brain injury and required invasive ventilation for at least 24 h. Demographic parameters, disease severity scores (Glasgow coma scale), comorbidities, vital signs, laboratory parameters and ventilator parameters were collected within the first 24 h of ICU admission. The main outcome was the relationship between MP and ICU mortality. A total of 529 patients were selected for the study. The critical value of MP was 12.16 J/min, with the area under the curve (AUC) of the MP was 0.678 (95% CI 0.637-0.718), and compared to the GCS scores, the MP performed significantly better in discrimination (DeLong's test: p < 0.001). Among these patients elevated MP was associated to higher ICU mortality (OR 1.11; 95% CI 1.06-1.17; p < 0.001), enhanced the risk of hospital mortality, prolonged ICU stay, and decreased the number of ventilator-free days. In the subgroup analysis, high MP was associated with ICU mortality regardless of ARDS (OR 1.01, 95% CI 1.00-1.02, p = 0.009; OR 1.01, 95% CI 1.00-1.02, p = 0.018, respectively) or obesity (OR 1.01, 95% CI 1.00-1.02, p = 0.012; OR 1.01, 95% CI 1.01-1.02, p < 0.001, respectively). In neurocritical care patients undergoing invasive ventilation, elevated MP is linked to higher ICU mortality and a variety of other clinical outcomes.

Extubation in neurocritical care patients: the ENIO international prospective study

PURPOSE

Neurocritical care patients receive prolonged invasive mechanical ventilation (IMV), but there is poor specific information in this high-risk population about the liberation strategies of invasive mechanical ventilation.

METHODS

ENIO (NCT03400904) is an international, prospective observational study, in 73 intensive care units (ICUs) in 18 countries from 2018 to 2020. Neurocritical care patients with a Glasgow Coma Score (GCS) ≤ 12, receiving IMV ≥ 24 h, undergoing extubation attempt or tracheostomy were included. The primary endpoint was extubation failure by day 5. An extubation success prediction score was created, with 2/3 of patients randomly allocated to the training cohort and 1/3 to the validation cohort. Secondary endpoints were the duration of IMV and in-ICU mortality.

RESULTS

1512 patients were included. Among the 1193 (78.9%) patients who underwent an extubation attempt, 231 (19.4%) failures were recorded. The score for successful extubation prediction retained 20 variables as independent predictors. The area under the curve (AUC) in the training cohort was 0.79 95% confidence interval (CI₉₅) [0.71-0.87] and 0.71 CI₉₅ [0.61-0.81] in the validation cohort. Patients with extubation failure displayed a longer IMV duration (14 [7-21] vs 6 [3-11] days) and a higher in-ICU mortality rate (8.7% vs 2.4%). Three hundred and nineteen (21.1%) patients underwent tracheostomy without extubation attempt. Patients with direct tracheostomy displayed a longer duration of IMV and higher in-ICU mortality than patients with an extubation attempt (success and failure).

CONCLUSIONS

In neurocritical care patients, extubation failure is high and is associated with unfavourable outcomes. A score could predict extubation success in multiple settings. However, it will be mandatory to validate our findings in another prospective independent cohort.

Development and validation of a RASS-related nomogram to predict the in-hospital mortality of neurocritical patients: a retrospective analysis based on the MIMIC-IV clinical database

BACKGROUND

Richmond agitation-sedation scale (RASS) is a simple and widely used tool for evaluating sedation and agitation in adult ICU patients. Early deep sedation has been shown to be an important independent predictor of death, however, studies on the role of RASS in the prognostic assessment of neurocritical patients are lacking. The purpose of this study was to investigate the relationship between RASS and in-hospital mortality in neurocritical patients, and to develop and validate an effective predictive model based on this.

METHODS

This was a retrospective study of neurocritical patients from a large clinical database. A total of 2651 patients were collected, including general demographic characteristics, past medical history, biochemical test data and physical examination within 24 h of admission, and related medical records. Univariate and multivariate logistic regression analyses were used to screen out significant variables. Finally, 11 significant predictors were included into the logistic regression to establish the nomogram.

RESULTS

The area under the curve (AUC) of the nomogram was 0.9087(0.8950-0.9224) and the corrected c index was 0.9043, which gave the model better discriminatory ability compared with critical care related scales, such as SOFA and SAPSII scores. Besides, tools including calibration curve, decision curve analysis (DCA), and clinical impact curve (CIC) were used to verify that the model had good discrimination, calibration, and clinical applicability.

CONCLUSIONS

RASS score was an independent prognostic predictor of in-hospital death in neurocritical patients, and patients who are deeply sedated have a worse prognosis. RASS-related nomogram could be applied to predict the prognosis of neurocritical patients and to take effective intervention measures in early stage.

Mechanical ventilation in acute brain injury patients with acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is commonly seen in patients with acute brain injury (ABI), with prevalence being as high as 35%. These patients often have additional risk factors for ARDS compared to general critical care patients. Lung injury in ABI occurs secondary to catecholamine surge and neuro-inflammatory processes. ARDS patients benefit from lung protective ventilation using low tidal volumes, permissive hypercapnia, high PEEP, and lower PO2 goals. These strategies can often be detrimental in ABI given the risk of brain hypoxia and elevation of intracranial pressure (ICP). While lung protective ventilation is not contraindicated in ABI, special consideration is warranted to make sure it does not interfere with neurological recovery. Permissive hypercapnia with low lung volumes can be utilized in patients without any ICP issues but those with ICP elevations can benefit from continuous ICP monitoring to personalize PCO2 goals. Hypoxia leads to poor outcomes in ABI, hence the ARDSnet protocol of lower PO2 target (55–80 mmHg) might not be the best practice in patients with concomitant ARDS and ABI. High-normal PO2 levels are reasonable in target in severe ABI with ARDS. Studies have shown that PEEP up to 12 mmHg does not cause significant elevations in ICP and is safe to use in ABI though mean arterial pressure, respiratory system compliance, and cerebral perfusion pressure should be closely monitored. Given most trials investigating therapeutics in ARDS have excluded ABI patients, focused research is needed in the field to advance the care of these patients using evidence-based medicine.

Validation of the flow index to detect low inspiratory effort during pressure support ventilation

Background

Bedside assessment of low levels of inspiratory effort, which are probably insufficient to prevent muscle atrophy, is challenging. The flow index, which is derived from the analysis of the inspiratory portion of the flow–time waveform, has been recently introduced as a non-invasive parameter to evaluate the inspiratory effort. The primary objective of the present study was to provide an external validation of the flow index to detect low inspiratory effort.

Methods

Datasets containing flow, airway pressure, and esophageal pressure (P_es)–time waveforms were obtained from a previously published study in 100 acute brain-injured patients undergoing pressure support ventilation. Waveforms data were analyzed offline. A low inspiratory effort was defined by one of the following criteria, work of breathing (WOB) less than 0.3 J/L, P_es–time product (PTP_es) per minute less than 50 cmH₂O•s/min, or inspiratory muscle pressure (P_mus) less than 5 cmH₂O, adding “or occurrence of ineffective effort more than 10%” for all criteria. The flow index was calculated according to previously reported method. The association of flow index with P_es-derived parameters of effort was investigated. The diagnostic accuracy of the flow index to detect low effort was analyzed.

Results

Moderate correlations were found between flow index and WOB, P_mus, and PTP_es per breath and per minute (Pearson’s correlation coefficients ranged from 0.546 to 0.634, P < 0.001). The incidence of low inspiratory effort was 62%, 51%, and 55% using the definition of WOB, PTP_es per minute, and P_mus, respectively. The area under the receiver operating characteristic curve for flow index to diagnose low effort was 0.88, 0.81, and 0.88, for the three respective definition. By using the cutoff value of flow index less than 2.1, the diagnostic performance for the three definitions showed sensitivity of 0.95–0.96, specificity of 0.57–0.71, positive predictive value of 0.70–0.84, and negative predictive value of 0.90–0.93.

Conclusions

The flow index is associated with P_es-based inspiratory effort measurements. Flow index can be used as a valid instrument to screen low inspiratory effort with a high probability to exclude cases without the condition.

Weaning Outcomes in Patients with Brain Injury

BACKGROUND

Despite the need for specific weaning strategies in neurological patients, evidence is generally insufficient or lacking. We aimed to describe the evolution over time of weaning and extubation practices in patients with acute brain injury compared with patients who are mechanically ventilated (MV) due to other reasons.

METHODS

We performed a secondary analysis of three prospective, observational, multicenter international studies conducted in 2004, 2010, and 2016 in adults who had need of invasive MV for more than 12 h. We collected data on baseline characteristics, variables related to management ventilator settings, and complications while patients were ventilated or until day 28.

RESULTS

Among the 20,929 patients enrolled, we included 12,618 (60%) who started the weaning from MV, of whom 1722 (14%) were patients with acute brain injury. In the acutely brain-injured cohort, 538 patients (31%) did not undergo planned extubation, defined as the need for a tracheostomy without an attempt of extubation, accidental extubation, and death. Among the 1184 planned extubated patients with acute brain injury, 202 required reintubation (17%). Patients with acute brain injury had a higher odds for unplanned extubation (odds ratio [OR] 1.35, confidence interval for 95% [CI 95%] 1.19-1.54; p < 0.001), a higher odds of failure after the first attempt of weaning (spontaneous breathing trial or gradual reduction of ventilatory support; OR 1.14 [CI 95% 1.01-1.30; p = 0.03]), and a higher odds for reintubation (OR 1.41 [CI 95% 1.20-1.66; p < 0.001]) than patients without brain injury. Patients with hemorrhagic stroke had the highest odds for unplanned extubation (OR 1.47 [CI 95% 1.22-1.77; p < 0.001]), of failed extubation after the first attempt of weaning (OR 1.28 [CI 95% 1.06-1.55; p = 0.009]), and for reintubation (OR 1.49 [CI 95% 1.17-1.88; p < 0.001]). In relation to weaning evolution over time in patients with acute brain injury, the risk for unplanned extubation showed a downward trend; the risk for reintubation was not associated to time; and there was a significant increase in the percentage of patients who underwent extubation after the first attempt of weaning from MV.

CONCLUSIONS

Patients with acute brain injury, compared with patients without brain injury, present higher odds of undergoing unplanned extubated after weaning was started, lower odds of being extubated after the first attempt, and a higher risk of reintubation.

Prophylactic acid suppressants in patients with primary neurologic injury: A systematic review and meta-analysis of randomized controlled trials

PURPOSE

Neurocritical care patients are at risk of stress-induced gastrointestinal ulceration. We performed a systematic review and meta-analysis of stress ulcer prophylaxis (SUP) in critically ill adults admitted with a primary neurologic injury.

MATERIALS AND METHODS

We included randomized controlled trials (RCTs) comparing SUP with histamine-2-receptor antagonists (H2RAs) or proton pump inhibitors (PPIs) to placebo/no prophylaxis, as well as to each other. The primary outcome was in-ICU gastrointestinal bleeding (GIB). Predefined secondary outcomes were all-cause 30-day mortality, ICU length of stay (LOS), nosocomial pneumonia, and other complications.

RESULTS

We identified 14 relevant trials enrolling 1036 neurocritical care patients; 11 trials enrolling 930 patients were included in the meta-analysis. H2RAs resulted in a lower incidence of GIB as compared to placebo or no prophylaxis (Risk ratio [RR] 0.42, 95% CI 0.30-0.58; p < 0.001); PPIs with a lower risk of GIB compared to placebo/no prophylaxis (RR 0.37, 95% CI 0.23-0.59; p < 0.001). No significant difference was observed in GIB comparing PPIs with H2RAs (RR 0.53, 95% CI 0.26-1.06; p = 0.07; I² = 0%).

CONCLUSIONS

In neurocritical care patients, the overall high or unclear risk of bias of individual trials, the low event rates, and modest sample sizes preclude strong clinical inferences about the utility of SUP.

Quantitative EEG may predict weaning failure in ventilated patients on the neurological intensive care unit

Neurocritical patients suffer from a substantial risk of extubation failure. The aim of this prospective study was to analyze if quantitative EEG (qEEG) monitoring is able to predict successful extubation in these patients. We analyzed EEG-monitoring for at least six hours before extubation in patients receiving mechanical ventilation (MV) on our neurological intensive care unit (NICU) between November 2017 and May 2019. Patients were divided in 2 groups: patients with successful extubation (SE) versus patients with complications after MV withdrawal (failed extubation; FE), including reintubation, need for non-invasive ventilation (NIV) or death. Bipolar six channel EEG was applied. Unselected raw EEG signal underwent automated artefact rejection and Short Time Fast Fourier Transformation. The following relative proportions of global EEG spectrum were analyzed: relative beta (RB), alpha (RA), theta (RT), delta (RD) as well as the alpha delta ratio (ADR). Coefficient of variation (CV) was calculated as a measure of fluctuations in the different power bands. Mann-Whitney U test and logistic regression were applied to analyze group differences. 52 patients were included (26 male, mean age 65 ± 17 years, diagnosis: 40% seizures/status epilepticus, 37% ischemia, 13% intracranial hemorrhage, 10% others). Successful extubation was possible in 40 patients (77%), reintubation was necessary in 6 patients (12%), 5 patients (10%) required NIV, one patient died. In contrast to FE patients, SE patients showed more stable EEG power values (lower CV) considering all EEG channels (RB: p < 0.0005; RA: p = 0.045; RT: p = 0.045) with RB as an independent predictor of weaning success in logistic regression (p = 0.004). The proportion of the EEG frequency bands (RB, RA RT, RD) of the entire EEG power spectrum was not significantly different between SE and FE patients. Higher fluctuations in qEEG frequency bands, reflecting greater fluctuation in alertness, during the hours before cessation of MV were associated with a higher rate of complications after extubation in this cohort. The stability of qEEG power values may represent a non-invasive, examiner-independent parameter to facilitate weaning assessment in neurocritical patients.

Prolonged Mechanical Ventilation: Outcomes and Management

The number of patients requiring prolonged mechanical ventilation (PMV) is increasing worldwide, placing a burden on healthcare systems. Therefore, investigating the pathophysiology, risk factors, and treatment for PMV is crucial. Various underlying comorbidities have been associated with PMV. The pathophysiology of PMV includes the presence of an abnormal respiratory drive or ventilator-induced diaphragm dysfunction. Numerous studies have demonstrated that ventilator-induced diaphragm dysfunction is related to increases in in-hospital deaths, nosocomial pneumonia, oxidative stress, lung tissue hypoxia, ventilator dependence, and costs. Thus far, the pathophysiologic evidence for PMV has been derived from clinical human studies and experimental studies in animals. Moreover, recent studies have demonstrated the outcome benefits of pharmacological agents and rehabilitative programs for patients requiring PMV. However, methodological limitations affected these studies. Controlled prospective studies with an adequate number of participants are necessary to provide evidence of the mechanism, prognosis, and treatment of PMV. The great epidemiologic impact of PMV and the potential development of treatment make this a key research field.

Physiological and Pathophysiological Consequences of Mechanical Ventilation

Mechanical ventilation is a life-support system used to ensure blood gas exchange and to assist the respiratory muscles in ventilating the lung during the acute phase of lung disease or following surgery. Positive-pressure mechanical ventilation differs considerably from normal physiologic breathing. This may lead to several negative physiological consequences, both on the lungs and on peripheral organs. First, hemodynamic changes can affect cardiovascular performance, cerebral perfusion pressure (CPP), and drainage of renal veins. Second, the negative effect of mechanical ventilation (compression stress) on the alveolar-capillary membrane and extracellular matrix may cause local and systemic inflammation, promoting lung and peripheral-organ injury. Third, intra-abdominal hypertension may further impair lung and peripheral-organ function during controlled and assisted ventilation. Mechanical ventilation should be optimized and personalized in each patient according to individual clinical needs. Multiple parameters must be adjusted appropriately to minimize ventilator-induced lung injury (VILI), including: inspiratory stress (the respiratory system inspiratory plateau pressure); dynamic strain (the ratio between tidal volume and the end-expiratory lung volume, or inspiratory capacity); static strain (the end-expiratory lung volume determined by positive end-expiratory pressure [PEEP]); driving pressure (the difference between the respiratory system inspiratory plateau pressure and PEEP); and mechanical power (the amount of mechanical energy imparted as a function of respiratory rate). More recently, patient self-inflicted lung injury (P-SILI) has been proposed as a potential mechanism promoting VILI. In the present chapter, we will discuss the physiological and pathophysiological consequences of mechanical ventilation and how to personalize mechanical ventilation parameters.

A novel nomogram to predict mortality in patients with stroke: a survival analysis based on the MIMIC-III clinical database

Background

Stroke is a disease characterized by sudden cerebral ischemia and is the second leading cause of death worldwide. We aimed to develop and validate a nomogram model to predict mortality in intensive care unit patients with stroke.

Methods

All data involved in this study were extracted from the Medical Information Mart for Intensive Care III database (MIMIC-III). The data were analyzed using multivariate Cox regression, and the performance of the novel nomogram, which assessed the patient’s overall survival at 30, 180, and 360 days after stroke, was evaluated using Harrell’s concordance index (C-index) and the area under the receiver operating characteristic curve. A calibration curve and decision curve were introduced to test the clinical value and effectiveness of our prediction model.

Results

A total of 767 patients with stroke were randomly divided into derivation (n = 536) and validation (n = 231) cohorts at a 7:3 ratio. Multivariate Cox regression showed that 12 independent predictors, including age, weight, ventilation, cardiac arrhythmia, metastatic cancer, explicit sepsis, Oxford Acute Severity of Illness Score or OASIS score, diastolic blood pressure, bicarbonate, chloride, red blood cell and white blood cell counts, played a significant role in the survival of individuals with stroke. The nomogram model was validated based on the C-indices, calibration plots, and decision curve analysis results.

Conclusions

The plotted nomogram accurately predicted stroke outcomes and, thus may contribute to clinical decision-making and treatment as well as consultation services for patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12911-022-01836-3.

Pulmonary complications and respiratory management in neurocritical care: a narrative review

ABSTRACT

Neurocritical care (NCC) is not only generally guided by principles of general intensive care, but also directed by specific goals and methods. This review summarizes the common pulmonary diseases and pathophysiology affecting NCC patients and the progress made in strategies of respiratory support in NCC. This review highlights the possible interactions and pathways that have been revealed between neurological injuries and respiratory diseases, including the catecholamine pathway, systemic inflammatory reactions, adrenergic hypersensitivity, and dopaminergic signaling. Pulmonary complications of neurocritical patients include pneumonia, neurological pulmonary edema, and respiratory distress. Specific aspects of respiratory management include prioritizing the protection of the brain, and the goal of respiratory management is to avoid inappropriate blood gas composition levels and intracranial hypertension. Compared with the traditional mode of protective mechanical ventilation with low tidal volume (Vt), high positive end-expiratory pressure (PEEP), and recruitment maneuvers, low PEEP might yield a potential benefit in closing and protecting the lung tissue. Multimodal neuromonitoring can ensure the safety of respiratory maneuvers in clinical and scientific practice. Future studies are required to develop guidelines for respiratory management in NCC.

End-of-Life Decisions of Intracranial Hemorrhage Patients Successfully Weaned From Prolonged Mechanical Ventilation

Factors related to the end-of-life decisions of patients with intracranial hemorrhage who were successfully weaned from prolonged mechanical ventilation remain unclear. This study aimed to evaluate factors that influence the end-of-life decisions of these patients. Methods: This retrospective study examined patients with intracranial hemorrhage successfully weaned from prolonged mechanical ventilation between January 2012 and December 2017. The following data was collected and analyzed: age, gender, comorbidities, Glasgow Coma Scale scores, receipt or non-receipt of intracranial hemorrhage surgery, discharge status, and end-of-life decisions.Results: In total, 91 patients with intracranial hemorrhage were successfully weaned from prolonged mechanical ventilation. The families of 62 (68.1%) patients signed the do-not-resuscitate order. A Glasgow Coma Scale score of ≥10 at discharge from the respiratory care center and zero comorbidities were the influencing factors between patients whose do-not-resuscitate orders were signed and those whose orders were not signed. Patients with intracranial hemorrhage successfully weaned from prolonged mechanical ventilation had chronic kidney disease comorbidity and Glasgow Coma Scale score of <7 on admission to respiratory care center with a general ward mortality rate of 83.3%.Conclusions: The families of intracranial hemorrhage patients with multiple comorbidities and higher neurologic impairment after successful weaning from the ventilator believed that palliative therapy would provide a greater benefit. Patients with intracranial hemorrhage successfully weaned from prolonged mechanical ventilation with chronic kidney disease comorbidity and Glasgow Coma Scale score of <7 on admission to respiratory care center are candidates for the consideration of hospice care with ventilator withdrawal.

The pattern of neurocritical disorders in multicenter in Khartoum State November 2020 to January 2021

BACKGROUND

Neurocritical care is a growing subspecialty. It concerns with the management of life-threatening neurological disorders. There is limited information regarding epidemiological data, disease characteristics, variability of clinical care, and in-hospital mortality of neurocritical patients worldwide.

OBJECTIVES

To study the pattern of neurocritical disorders in intensive care units.

METHODOLOGY

This prospective observational study was conducted on neurocritical patients who were admitted to four intensive care units of major hospitals in Khartoum state during the period from November 2020 to January 2021.

RESULTS

Seventy-two neurocritical patients were included in this study, 40 (55.6%) were males and 32(44.4%) were females. Twenty-three (31.9%) patients were with stroke, 12 (16.7%) with encephalitis, 9 (12.5%) with status epilepticus, 6 (8.3%) with Guillain Barre syndrome, and 4(5.6%) with Myasthenia Gravis (MG). Twenty-three patients (39.9%) needed mechanical ventilation (MV), which was the major indication for intensive care unit admission.

CONCLUSION

Stroke was the dominant diagnostic pattern requiring intensive care unit admission. Mechanical ventilation was the major indication for admission. Establishing specialized neurocritical intensive care units is highly recommended.

Outcome of neurocritical disorders, a multicenter prospective cross-sectional study

BACKGROUND

Patients with neurocritical disorders who require admission to intensive care units (ICUs) constitute about 10-15% of critical care cases.

OBJECTIVES

To study the outcome of neurocritical disorders in intensive care units.

METHODOLOGY

This is a prospective cross-sectional study that was conducted among neurocritical patients who were admitted in four intensive care units of four major hospitals in Khartoum state during the period from November 2020 to March 2021.

RESULTS

Seventy-two neurocritical patients were included in this study; 40(55.6%) were males and 32(44.4%) were females. Twenty-one (29.2%) patients fully recovered, 35 (48.6%) partially recovered and 16 (22.2%) died. The mortality of the common neurocritical diseases were as follows: stroke 30.4%, encephalitis (8.3%), status epilepticus (11.1%), Guillain-Barre syndrome (GBS) (16.7%), and myasthenia gravis (MG) (25%).

CONCLUSION

This study identified that near two-thirds of the patients required mechanical ventilation. Delayed admission was observed due to causes distributed between the medical side and patient side. The majority of patients were discharged from ICU with partial recovery.

Predictors of Prolonged Mechanical Ventilation Among Patients with Aneurysmal Subarachnoid Hemorrhage After Microsurgical Clipping

Introduction

Aneurysmal subarachnoid hemorrhage (aSAH) is a fatal event with high mortality and morbidity rates. Survivors may require prolonged intubation with mechanical ventilation (MV). However, the risk factors for prolonged intubation in these patients remain unclear. The aim of this study was to determine the predictors of prolonged MV in aSAH patients who underwent surgical clipping.

Methods

In total, 108 adult patients with a primary diagnosis of aSAH who were on MV > 48 h and survived > 14 days after surgery were included. Clinicodemographic and radiological characteristics, laboratory tests on admission, and initial Glasgow Coma Scale (GCS) and its components were analyzed.

Results

The average age of the patients included in the analysis was 59.1 ± 12.5 years. Overall, 32 patients (29.6%) had prolonged MV. The group with prolonged MV showed a higher prevalence of diabetes mellitus and hypertension, lower initial GCS and its components, higher World Federation of Neurosurgeons (WFNS) and Hunt and Hess grades, and higher initial white cell counts. The independent factors associated with prolonged MV were a history of diabetes mellitus (odds ratio [OR] 5.799, 95% confidence interval [CI] 1.109–30.334; P = 0.037) and Hunt and Hess grade 3–5 (OR 7.217, 95% CI 1.090–47.770; P = 0.040).

Conclusion

A history of diabetes mellitus and Hunt and Hess grade 3–5 independently predict prolonged MV after microsurgical clipping in patients with aSAH. Thus, knowledge of potential predictors for prolonged MV is essential to improve the early initiation of adequate treatment in the early stages of treatment and provide useful information for communication between caregivers and families.

Effects of positive end-expiratory pressure on lung ultrasound patterns and their correlation with intracranial pressure in mechanically ventilated brain injured patients

Background

The effects of positive end-expiratory pressure (PEEP) on lung ultrasound (LUS) patterns, and their relationship with intracranial pressure (ICP) in brain injured patients have not been completely clarified. The primary aim of this study was to assess the effect of two levels of PEEP (5 and 15 cmH₂O) on global (LUStot) and regional (anterior, lateral, and posterior areas) LUS scores and their correlation with changes of invasive ICP. Secondary aims included: the evaluation of the effect of PEEP on respiratory mechanics, arterial partial pressure of carbon dioxide (PaCO₂) and hemodynamics; the correlation between changes in ICP and LUS as well as respiratory parameters; the identification of factors at baseline as potential predictors of ICP response to higher PEEP.

Methods

Prospective, observational study including adult mechanically ventilated patients with acute brain injury requiring invasive ICP. Total and regional LUS scores, ICP, respiratory mechanics, and arterial blood gases values were analyzed at PEEP 5 and 15 cmH₂O.

Results

Thirty patients were included; 19 of them (63.3%) were male, with median age of 65 years [interquartile range (IQR) = 66.7–76.0]. PEEP from 5 to 15 cmH₂O reduced LUS score in the posterior regions (LUSp, median value from 7 [5–8] to 4.5 [3.7–6], p = 0.002). Changes in ICP were significantly correlated with changes in LUStot (rho = 0.631, p = 0.0002), LUSp (rho = 0.663, p < 0.0001), respiratory system compliance (rho = − 0.599, p < 0.0001), mean arterial pressure (rho = − 0.833, p < 0.0001) and PaCO₂ (rho = 0.819, p < 0.0001). Baseline LUStot score predicted the increase of ICP with PEEP.

Conclusions

LUS-together with the evaluation of respiratory and clinical variables-can assist the clinicians in the bedside assessment and prediction of the effect of PEEP on ICP in patients with acute brain injury.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03903-7.

Noninvasive and invasive mechanical ventilation for neurologic disorders

Patients with acute neurologic injuries frequently require mechanical ventilation due to diminished airway protective reflexes, cardiopulmonary failure secondary to neurologic insults, or to facilitate gas exchange to precise targets. Mechanical ventilation enables tight control of oxygenation and carbon dioxide levels, enabling clinicians to modulate cerebral hemodynamics and intracranial pressure with the goal of minimizing secondary brain injury. In patients with acute spinal cord injuries, neuromuscular conditions, or diseases of the peripheral nerve, mechanical ventilation enables respiratory support under conditions of impending or established respiratory failure. Noninvasive ventilatory approaches may be carefully considered for certain disease conditions, including myasthenia gravis and amyotrophic lateral sclerosis, but may be inappropriate in patients with Guillain-Barré syndrome or when relevant contra-indications exist. With regard to discontinuing mechanical ventilation, considerable uncertainty persists about the best approach to wean patients, how to identify patients ready for extubation, and when to consider primary tracheostomy. Recent consensus guidelines highlight these and other knowledge gaps that are the focus of active research efforts. This chapter outlines important general principles to consider when initiating, titrating, and discontinuing mechanical ventilation in patients with acute neurologic injuries. Important disease-specific considerations are also reviewed where appropriate.