Retrospective analysis of the risk factors and pathogens associated with early-onset ventilator-associated pneumonia in surgical-ICU head-trauma patients. J Neurosurg Anesthesiol. 2010;22:32-37. [PMID: 20027012 DOI: 10.1097/ana.0b013e3181bdf52f]

Risk factors and outcomes of ventilator-associated pneumonia in patients with traumatic brain injury: A systematic review and meta-analysis

BACKGROUND

Ventilator-associated pneumonia (VAP) is a common complication in traumatic brain injury (TBI) patients, which increases morbidity and negatively affects outcomes. Risk factors and outcomes in these patients remain controversial. The aim of the present study is to explore the risk factors and clinical outcomes of patients with VAP and TBI.

METHODS

Two researchers conducted independent systematic literature searches of Pubmed, Cochrane Database, Scopus, Medline Ovid, Science Direct databases, published from inception to January 2024. The Newcastle-Ottawa scale was used to assess study quality. A meta-analysis was performed using a random-effects model when heterogeneity I2 > 50 % and a fixed-effects model when I2 < 50 %; in addition, a subgroup analysis was performed to explore VAP risk factors, and publication bias was assessed with the funnel plot and Begg's and Egger's tests. All results were considered statistically significant when p < 0.05. The certainty of the evidence was evaluated using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) methodology.

RESULTS

Twelve studies were included in the meta-analysis with a total of 2883 patients. Male gender [OR 1.58 (95 % CI 1.23, 2.02) p < 0.05 I2 0 %] and abbreviated injury scale (head: H-AIS) [≥ 3 OR 2.79 (95 % CI 1.58, 4.93) p < 0.05 I2 0 %] increased the risk of VAP. After subgroup analysis, blood transfusion on admission [OR 1.97 (95 % CI 1.16-3.35) p ≤0.05 I2 5 %] and barbiturate infusion [OR 3.55 (95 % CI 2.01-6.30) p ≤0.05 I2 0 %] became risk factors. Prophylactic antibiotic use [OR 0.67 (95 % CI 0.51-0.88) p ≤0.05 I2 0 %] and younger age MD -3.29 (95 % CI -5.18, -1.40) p ≤0.05 I2 41 %] emerged as significant protective factors. In VAP patients ICU stay [MD 7.02 (95 % CI 6.05-7.99) p ≤0.05 I2 37 %], duration of mechanical ventilation [MD 5.79 (95 % CI 4.40, 7.18) p ≤0.05 I2 79 %] and hospital stay [MD 11.88 (95 % CI 8.71-15.05) p ≤0.05 I2 0 %] were significantly increased. The certainty of the evidence was moderate-high for the outcomes studied.

CONCLUSIONS

Male gender, H-AIS ≥ 3, blood transfusion on admission, and barbiturate infusion were risk factors for VAP. In patients with VAP, ICU stay, duration of mechanical ventilation, hospital stay were significantly increased.

Predicting the Risk of In-Hospital Mortality in Traumatic Brain Injury Patients on Invasive Mechanical Ventilation in the Intensive Care Unit: Construction and Validation of an Online Nomogram

OBJECTIVE

To explore mortality risk factors and to construct an online nomogram for predicting in-hospital mortality in traumatic brain injury (TBI) patients receiving invasive mechanical ventilation (IMV) in intensive care unit (ICU).

METHODS

We retrospectively analyzed TBI patients on IMV in ICU from Medical Information Mart for Intensive Care IV database and 2 hospitals. Least absolute shrinkage and selection operation regression and multiple logistic regression were used to detect predictors of in-hospital mortality and to construct an online nomogram. The predictive performance of nomogram was evaluated using area under the receiver operating characteristic curves (AUC), calibration curves, decision curve analysis, and clinical impact curves.

RESULTS

Five hundred ten from Medical Information Mart for Intensive Care IV database were enrolled for nomogram construction (80%, n = 408) and internal validation (20%, n = 102). One hundred eighty-five from 2 hospitals were enrolled for external validation. Least absolute shrinkage and selection operation-logistic regression revealed predictors of in-hospital mortality among TBI patients on IMV in ICU included Glasgow Coma Scale (GCS) after ICU admission, Acute Physiology Score III (APS III) after ICU admission, neutrophil and lymphocyte ratio after IMV, blood urea nitrogen after IMV, arterial serum lactate after IMV, and in-hospital tracheotomy. The AUC, calibration curves, decision curve analysis, and clinical impact curves indicated the nomogram had good discrimination, calibration, clinical benefit, and applicability. The multimodel comparisons revealed the nomogram had higher AUC than GCS, APS III, and Simplified Acute Physiology Score II.

CONCLUSIONS

We constructed and validated an online nomogram based on routinely recorded factors at admission to ICU and at the beginning of IMV to target prediction of in-hospital mortality among TBI patients on IMV in ICU.

Rebound Inverts the Staphylococcus aureus Bacteremia Prevention Effect of Antibiotic Based Decontamination Interventions in ICU Cohorts with Prolonged Length of Stay

Could rebound explain the paradoxical lack of prevention effect against Staphylococcus aureus blood stream infections (BSIs) with antibiotic-based decontamination intervention (BDI) methods among studies of ICU patients within the literature? Two meta-regression models were applied, each versus the group mean length of stay (LOS). Firstly, the prevention effects against S. aureus BSI [and S. aureus VAP] among 136 studies of antibiotic-BDI versus other interventions were analyzed. Secondly, the S. aureus BSI [and S. aureus VAP] incidence in 268 control and intervention cohorts from studies of antibiotic-BDI versus that among 165 observational cohorts as a benchmark was modelled. In model one, the meta-regression line versus group mean LOS crossed the null, with the antibiotic-BDI prevention effect against S. aureus BSI at mean LOS day 7 (OR 0.45; 0.30 to 0.68) inverted at mean LOS day 20 (OR 1.7; 1.1 to 2.6). In model two, the meta-regression line versus group mean LOS crossed the benchmark line, and the predicted S. aureus BSI incidence for antibiotic-BDI groups was 0.47; 0.09-0.84 percentage points below versus 3.0; 0.12-5.9 above the benchmark in studies with 7 versus 20 days mean LOS, respectively. Rebound within the intervention groups attenuated and inverted the prevention effect of antibiotic-BDI against S. aureus VAP and BSI, respectively. This explains the paradoxical findings.

Management of Ventilator-Associated Pneumonia: Guidelines

Two recent major guidelines on diagnosis and treatment of ventilator-associated pneumonia (VAP) recommend consideration of local antibiotic resistance patterns and individual patient risks for resistant pathogens when formulating an initial empiric antibiotic regimen. One recommends against invasive diagnostic techniques with quantitative cultures to determine the cause of VAP; the other recommends either invasive or noninvasive techniques. Both guidelines recommend short-course therapy be used for most patients with VAP. Although neither guideline recommends use of procalcitonin as an adjunct to clinical judgment when diagnosing VAP, they differ with respect to use of serial procalcitonin to shorten the length of antibiotic treatment.

Derivation and validation of a quantitative risk prediction model for weaning and extubation in neurocritical patients

Background

Patients with severe neurological conditions are at high risk during withdrawal and extubation, so it is important to establish a model that can quantitatively predict the risk of this procedure.

Methods

By analyzing the data of patients with traumatic brain injury and tracheal intubation in the ICU of the affiliated hospital of Hangzhou Normal University, a total of 200 patients were included, of which 140 were in the modeling group and 60 were in the validation group. Through binary logistic regression analysis, 8 independent risk factors closely related to the success of extubation were screened out, including age ≥ 65 years old, APACHE II score ≥ 15 points, combined chronic pulmonary disease, GCS score < 8 points, oxygenation index <300, cough reflex, sputum suction frequency, and swallowing function.

Results

Based on these factors, a risk prediction scoring model for extubation was constructed with a critical value of 18 points. The AUC of the model was 0.832, the overall prediction accuracy was 81.5%, the specificity was 81.6%, and the sensitivity was 84.1%. The data of the validation group showed that the AUC of the model was 0.763, the overall prediction accuracy was 79.8%, the specificity was 84.8%, and the sensitivity was 64.0%.

Conclusion

These results suggest that the extubation risk prediction model constructed through quantitative scoring has good predictive accuracy and can provide a scientific basis for clinical practice, helping to assess and predict extubation risk, thereby improving the success rate of extubation and improving patient prognosis.

Risk factors of second ventilator-associated pneumonia in trauma patients: a retrospective cohort study

BACKGROUND

Ventilator acquired pneumonia (VAP) is a frequent and serious complication in ICU. Second episodes of VAP are common in trauma patients and may be related to severity of underlying conditions, treatment or bacterial factors of the first VAP. The aim of this study was to identify risk factors of second VAP episodes in trauma injured patients (defined as the development of a new pulmonary infection during or remotely following the first episode).

DESIGN

This is a single-center, retrospective cohort study of trauma injured patients who underwent a first episode of VAP between January 1, 2013 and December 31, 2020 at Beaujon Hospital.

RESULTS

A total of 533 patients with a first episode of VAP were analyzed, mostly with head and/or thoracic traumatic injury. A second episode of VAP occurred in one hundred sixty-seven patients (31.3%). The main risk factors found was the degree of hypoxemia at the time of the first episode [PaO2/FiO2 ratio 100-200, OR 3.12 (1.77-5.69); < 100, OR 5.80 (2.70-12.8)] and severe traumatic brain injury characterized by an initial GCS ≤ 8 [OR 1.65 (1.01-2.74)].

CONCLUSION

Depth of hypoxemia during the first VAP episode and severity of the initial brain injury are the main risk factors for VAP second episode in trauma injured patients.

Is severe traumatic brain injury no longer a contraindication for surgical stabilization of rib fractures in patients with multiple rib fractures? A propensity-matched analysis

BACKGROUND

Traumatic brain injury (TBI) is often considered a contraindication to surgical stabilization of rib fractures (SSRF). In this study, we hypothesized that, compared with nonoperative management, SSRF is associated with improved outcomes in TBI patients.

METHODS

Using the American College of Surgeons Trauma Quality Improvement Program 2016-2019, we performed a retrospective analysis of patients with concurrent TBI and multiple rib fractures. Following propensity score matching, we compared patients who underwent SSRF with those who were managed nonoperatively. Our primary outcome was mortality. Secondary outcomes included ventilator-associated pneumonia, hospital and intensive care unit (ICU) length of stay (LOS), ventilator days, tracheostomy rate, and hospital discharge disposition. In a subgroup analysis, we stratified patients into mild and moderate TBI (GCS score >8) and severe TBI (GCS score ≤8).

RESULTS

Of 36,088 patients included in this study, 879 (2.4%) underwent SSRF. After propensity-score matching, compared with nonoperative management, SSRF was associated with decreased mortality (5.4% vs. 14.5%, p < 0.001), increased hospital LOS (15 days vs. 9 days, p < 0.001), increased ICU LOS (12 days vs. 8 days, p < 0.001), and increased ventilator days (7 days vs. 4 days, p < 0.001). In the subgroup analyses, in mild and moderate TBI, SSRF was associated with decreased in-hospital mortality (5.0% vs. 9.9%, p = 0.006), increased hospital LOS (13 days vs. 9 days, p < 0.001), ICU LOS (10 days vs. 7 days, p < 0.001), and ventilator days (5 days vs. 2 days, p < 0.001). In patients with severe TBI, SSRF was associated with decreased mortality (6.2% vs. 18%, p < 0.001), increased hospital LOS (20 days vs. 14 days, p = 0.001), and increased ICU LOS (16 days vs. 13 days, p = 0.004).

CONCLUSION

In patients with TBI and multiple rib fractures, SSRF is associated with a significant decrease in in-hospital mortality and with longer hospital and ICU LOSs. These findings suggest that SSRF should be considered in patients with TBI and multiple rib fractures.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

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.

Early use of barbiturates is associated with increased mortality in traumatic brain injury patients from a propensity score-based analysis of a prospective cohort

Barbiturates are proposed as a second/third line treatment for intracranial hypertension in traumatic brain injury (TBI) patients, but the literature remains uncertain regarding their benefit/risk balance. We aimed to evaluate the impact of barbiturates therapy in TBI patients with early intracranial hypertension on the intensive care unit (ICU) survival, the occurrence of ventilator-associated pneumonia (VAP), and the patient’s functional status at three months. We used the French AtlanREA prospective cohort of trauma patients. Using a propensity score-based methodology (inverse probability of treatment weighting), we compared patients having received barbiturates within the first 24 hours of admission (barbiturates group) and those who did not (control group). We used cause-specific Cox models for ICU survival and risk of VAP, and logistic regression for the 3-month Glasgow Outcome Scale (GOS) evaluation. Among the 1396 patients with severe trauma, 383 had intracranial hypertension on admission and were analyzed. Among them, 96 (25.1%) received barbiturates. The early use of barbiturates was significantly associated with increased ICU mortality (HR = 1.85, 95%CI 1.03–3.33). However, barbiturates treatment was not significantly associated with VAP (HR = 1.02, 95%CI 0.75–1.41) or 3-month GOS (OR = 1.67, 95%CI 0.84–3.33). Regarding the absence of relevant clinical trials, our results suggest that each early prescription of barbiturates requires a careful assessment of the benefit/risk ratio.

Central nervous system injury-induced immune suppression

Central nervous system trauma is a common cause of morbidity and mortality. Additionally, these injuries frequently occur in younger individuals, leading to lifetime expenses for patients and caregivers and the loss of opportunity for society. Despite this prevalence and multiple attempts to design a neuroprotectant, clinical trials for a pharmacological agent for the treatment of traumatic brain injury (TBI) or spinal cord injury (SCI) have provided disappointing results. Improvements in outcome from these disease processes in the past decades have been largely due to improvements in supportive care. Among the many challenges facing patients and caregivers following neurotrauma, posttraumatic nosocomial infection is a significant and potentially reversible risk factor. Multiple animal and clinical studies have provided evidence of posttraumatic systemic immune suppression, and injuries involving the CNS may be even more prone, leading to a higher risk for in-hospital infections following neurotrauma. Patients who have experienced neurotrauma with nosocomial infection have poorer recovery and higher risks of long-term morbidity and in-hospital mortality than patients without infection. As such, the etiology and reversal of postneurotrauma immune suppression is an important topic. There are multiple possible etiologies for these posttraumatic changes including the release of damage-associated molecular patterns, the activation of immunosuppressive myeloid-derived suppressor cells, and sympathetic nervous system activation. Postinjury systemic immunosuppression, particularly following neurotrauma, provides a challenge for clinicians but also an opportunity for improvement in outcome. In this review, the authors sought to outline the evidence of postinjury systemic immune suppression in both animal models and clinical research of TBI, TBI polytrauma, and SCI.

Prediction models of methicillin sensitive Staphylococcus aureus ventilator associated pneumonia relapse in trauma and brain injury patients: A retrospective analysis

PURPOSE

To describe the incidence and risk factors of methicillin sensitive Staphylococcus aureus ventilator associated pneumonia (MSSA-VAP) relapse in trauma and non-traumatic brain injury patients.

MATERIALS AND METHODS

Retrospective observational monocentric cohort study of consecutive ICU patients who developed a first episode of MSSA-VAP after trauma and non-traumatic brain injury. MSSA-VAP relapse encompass MSSA-VAP treatment failure (persistence or recurrence of MSSA) or other pathogen - VAP.

RESULTS

A total of 165 patients (71% of trauma and 29% of non-traumatic brain injury) with MSSA-VAP were included. MSSA-VAP relapse occurred in 54 (33%) patients, including 28 (17%) MSSA-VAP treatment failure and 46 (28%) other pathogen-VAP. Empirical first-line antibiotic therapy was appropriate in 96% of cases. In multivariate analysis, the presence of Streptococcus species (Odds ratio [OR] 7.37) and oropharyngeal flora (OR 3.64) as initial MSSA co-pathogen, suggested aspiration at the time of admission and independently predicted MSSA-VAP treatment failure. Initial Glasgow coma scale (OR 0.89), need for emergent surgery (OR 5.71) and the presence of an acute respiratory distress syndrome at the time of the first MSSA-VAP (3.99), independently predicted the onset of other pathogen - VAP.

CONCLUSION

Early and simple factors may help to identify patients with high-risk of MSSA-VAP relapse.

Could the Gut Microbiota Serve as a Therapeutic Target in Ischemic Stroke?

The brain-gut axis is a relatively recent discovery of a two-way regulation system between the gut and brain, suggesting that the gut microbiota may be a promising targeted prevention and treatment strategy for patients with a high risk of acute cerebral ischemia/reperfusion injury. There are many risk factors for ischemic stroke, and many studies have shown that the gut microbiota affects the absorption and metabolism of the body, as well as the risk factors of stroke, such as blood pressure, blood glucose, blood lipids, and atherosclerosis, either directly or indirectly. Furthermore, the gut microbiota can affect the occurrence and prognosis of ischemic stroke by regulating risk factors or immune responses. Therefore, this study aimed to collect evidence of the interaction between gut microbiota and ischemic stroke, summarize the interaction mechanism between the two, and explore the gut microbiota as a new targeted prevention and treatment strategy for patients with high ischemic risk.

Immunonutrition for traumatic brain injury in children and adolescents: protocol for a systematic review and meta-analysis

INTRODUCTION

Traumatic brain injury (TBI) is the leading cause of paediatric trauma death and disability worldwide. The 'Guidelines for the Management of Severe Traumatic Brain Injury (Fourth Edition)' recommend that nutritional goals should be achieved within 5-7 days of injury. Immune-enhancing nutrition or immunonutrition, referring to the addition of specialised nutrients, including glutamine, alanine, omega-3 fatty acids and nucleotides, to standard nutrition formulas, may improve surgical outcomes in the perioperative period. However, the role of immune-enhancing nutritional supplements for patients with paediatric TBI remains unclear. We will conduct a systematic review to determine the efficacy and safety of immunonutrition for patients with paediatric TBI and provide evidence for clinical decision-making.

METHODS AND ANALYSIS

Studies reporting immune-enhancing nutrition treatments for patients with paediatric TBI will be included. Outcomes of interest include the length of hospital stay, wound infections, all-cause mortality, non-wound infection, including pneumonia, urinary tract infection and bacteraemia, and the reports adverse events. Duration of follow-up has no restriction. Primary studies consisting of randomised controlled trials (RCTs) and non-RCTs will be eligible for this review, and only studies published in English will be included. We will search the Medline, Embase and Cochrane Library databases from their inception dates to January 2020. We will also search clinicaltrials.gov and the WHO International Clinical Trials Registry Platform for additional information. Two reviewers will independently select studies and extract data. Risk-of-bias will be assessed with tools based on the Cochrane risk-of-bias criteria and Newcastle-Ottawa Quality Assessment Scale. A meta-analysis will be used to pool data when there are sufficient studies with homogeneity. Heterogeneity of the estimates across studies will be assessed; if necessary, a subgroup analysis will be performed to explore the source of heterogeneity. The Grades of Recommendation, Assessment, Development and Evaluation method will be applied to assess the level of evidence obtained from this systematic review.

ETHICS AND DISSEMINATION

The proposed systematic review and meta-analysis will be based on published data, and thus ethical approval is not required. The results of this review will be published.

PROSPERO REGISTRATION NUMBER

CRD42020154814.

Crosstalk between brain, lung and heart in critical care

Extracerebral complications, especially pulmonary and cardiovascular, are frequent in brain-injured patients and are major outcome determinants. Two major pathways have been described: brain-lung and brain-heart interactions. Lung injuries after acute brain damages include ventilator-associated pneumonia (VAP), acute respiratory distress syndrome (ARDS) and neurogenic pulmonary œdema (NPE), whereas heart injuries can range from cardiac enzymes release, ECG abnormalities to left ventricle dysfunction or cardiogenic shock. The pathophysiologies of these brain-lung and brain-heart crosstalk are complex and sometimes interconnected. This review aims to describe the epidemiology and pathophysiology of lung and heart injuries in brain-injured patients with the different pathways implicated and the clinical implications for critical care physicians.

Incidence, Risk Factors, and Effects on Outcome of Ventilator-Associated Pneumonia in Patients With Traumatic Brain Injury: Analysis of a Large, Multicenter, Prospective, Observational Longitudinal Study

BACKGROUND

No large prospective data, to our knowledge, are available on ventilator-associated pneumonia (VAP) in patients with traumatic brain injury (TBI).

RESEARCH QUESTION

To evaluate the incidence, timing, and risk factors of VAP after TBI and its effect on patient outcome.

STUDY DESIGN AND METHODS

This analysis is of the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury data set, from a large, multicenter, prospective, observational study including patients with TBI admitted to European ICUs, receiving mechanical ventilation for ≥ 48 hours and with an ICU length of stay (LOS) ≥ 72 hours. Characteristics of patients with VAP vs characteristics of patients without VAP were compared, and outcome was assessed at 6 months after injury by using the Glasgow Outcome Scale Extended.

RESULTS

The study included 962 patients: 196 (20.4%) developed a VAP at a median interval of 5 days (interquartile range [IQR], 3-7 days) after intubation. Patients who developed VAP were younger (median age, 39.5 [IQR, 25-55] years vs 51 [IQR, 30-66] years; P < .001), with a higher incidence of alcohol abuse (36.6% vs 27.6%; P = .026) and drug abuse (10.1% vs 4.2%; P = .009), more frequent thoracic trauma (53% vs 43%; P = .014), and more episodes of respiratory failure during ICU stay (69.9% vs 28.1%; P < .001). Age (hazard ratio [HR], 0.99; 95% CI, 0.98-0.99; P = .001), chest trauma (HR, 1.4; 95% CI, 1.03-1.90; P = .033), histamine-receptor antagonist intake (HR, 2.16; 95% CI, 1.37-3.39; P = .001), and antibiotic prophylaxis (HR, 0.69; 95% CI, 0.50-0.96; P = .026) were associated with the risk of VAP. Patients with VAP had a longer duration of mechanical ventilation (median, 15 [IQR, 10-22] days vs 8 [IQR, 5-14] days; P < .001) and ICU LOS (median, 20 [IQR, 14-29] days vs 13 [IQR, 8-21] days; P < .001). However, VAP was not associated with increased mortality or worse neurological outcome. Overall mortality at 6 months was 22%.

INTERPRETATION

VAP occurs less often than previously described in patients after TBI and has a detrimental effect on ICU LOS but not on mortality and neurological outcome.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT02210221; URL: www.clinicaltrials.gov.

Injury intensifies T cell mediated graft-versus-host disease in a humanized model of traumatic brain injury

The immune system plays critical roles in promoting tissue repair during recovery from neurotrauma but is also responsible for unchecked inflammation that causes neuronal cell death, systemic stress, and lethal immunodepression. Understanding the immune response to neurotrauma is an urgent priority, yet current models of traumatic brain injury (TBI) inadequately recapitulate the human immune response. Here, we report the first description of a humanized model of TBI and show that TBI places significant stress on the bone marrow. Hematopoietic cells of the marrow are regionally decimated, with evidence pointing to exacerbation of underlying graft-versus-host disease (GVHD) linked to presence of human T cells in the marrow. Despite complexities of the humanized mouse, marrow aplasia caused by TBI could be alleviated by cell therapy with human bone marrow mesenchymal stromal cells (MSCs). We conclude that MSCs could be used to ameliorate syndromes triggered by hypercytokinemia in settings of secondary inflammatory stimulus that upset marrow homeostasis such as TBI. More broadly, this study highlights the importance of understanding how underlying immune disorders including immunodepression, autoimmunity, and GVHD might be intensified by injury.

Current Status of Indications, Timing, Management, Complications, and Outcomes of Tracheostomy in Traumatic Brain Injury Patients

Tracheostomy is the commonest bedside surgical procedure performed on patients needing mechanical ventilation with traumatic brain injury (TBI). The researchers made an effort to organize a narrative review of the indications, timing, management, complications, and outcomes of tracheostomy in relation to neuronal and brain-injured patients following TBI. The study observations were collated from the published literature, namely original articles, book chapters, case series, randomized studies, systematic reviews, and review articles. Information sorting was restricted to tracheostomy and its association with TBI. Care was taken to review the correlation of tracheostomy with clinical correlates including indications, scheduling, interventions, prognosis, and complications of the patients suffering from mild, moderate and severe TBIs using Glasgow Coma Scale, Glasgow Outcome Scale, intraclass correlation coefficient, and other internationally acclaimed outcome scales. Tracheostomy is needed to overcome airway obstruction, prolonged respiratory failure and as indispensable component of mechanical ventilation due to diverse reasons in intensive care unit. Researchers are divided over early tracheostomy or late tracheostomy from days to weeks. The conventional classic surgical technique of tracheostomy has been superseded by percutaneous techniques by being less invasive with lesser complications, classified into early and late complications that may be life threatening. Additional studies have to be conducted to validate and streamline varied observations to frame evidence-based practice for successful weaning and decannulation. Tracheostomy is a safer option in critically ill TBI patients for which a universally accepted protocol for tracheostomy is needed that can help to optimize indications and outcomes.

Incidence, Risk Factors, and Outcomes of Ventilator-Associated Pneumonia in Traumatic Brain Injury: A Meta-analysis

Ventilator-associated pneumonia (VAP) is one of the most severe complications in patients with traumatic brain injury (TBI) and is considered a risk factor for poor outcomes. However, the incidence of VAP among patients with TBI reported in studies varies widely. What is more, the risk factors and outcomes of VAP are controversial. This study estimates the incidence, risk factors, and outcomes of VAP in patients with TBI and provides evidence for prevention and treatment. PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched from the earliest records to May 2018. Data involving the incidence, risk factors, and outcomes were extracted for meta-analysis. The results showed that the incidence of VAP was 36% (95% confidence interval (CI) 31-41%); risk factors analyses showed that smoking [odds ratio (OR) 2.13; 95% CI 1.16-3.92], tracheostomy (OR 9.55; 95% CI 3.24-28.17), blood transfusion on admission (OR 2.54; 95% CI 1.24-5.18), barbiturate infusion (OR 3.52; 95% CI 1.68-7.40), injury severity score (OR 4.65; 95% CI 1.96-7.34), and head abbreviated injury scale (OR 2.99; 95% CI 1.66-5.37) were related to the occurrence of VAP. When patients developed VAP, mechanical ventilation time (OR 5.45; 95% CI 3.78-7.12), ICU length of stay (OR 6.85; 95% CI 4.90-8.79), and hospital length of stay (OR 10.92; 95% CI 9.12-12.72) were significantly increased. However, VAP was not associated with an increased risk of mortality (OR 1.28; 95% CI 0.74-2.21). VAP is common in patients with TBI. It is affected by a series of factors and has a poor prognosis.

Diagnostic Accuracy of Procalcitonin for Early Aspiration Pneumonia in Critically Ill Patients with Coma: A Prospective Study

BACKGROUND

Early diagnostic orientation for differentiating pneumonia from pneumonitis at the early stage after aspiration would be valuable to avoid unnecessary antibiotic therapy. We assessed the accuracy of procalcitonin (PCT) in diagnosing aspiration pneumonia (AP) in intensive care unit (ICU) patients requiring mechanical ventilation after out-of-hospital coma.

METHODS

Prospective observational 2-year cohort study in a medical-surgical ICU. PCT, C-reactive protein (CRP) and white blood cell count (WBC) were measured at admission (H0) and 6 h (H), H12, H24, H48, H96, and H120 after inclusion. Lower respiratory tract microbiological investigations performed routinely in patients with aspiration syndrome were the reference standard for diagnosing AP. Performance of PCT, CRP, and WBC up to H48 in diagnosing AP was compared based on the areas under the ROC curves (AUC) and likelihood ratios (LR+ and LR-) computed for the best cutoff values.

RESULTS

Of 103 patients with coma, 45 (44%) had AP. Repeated PCT assays demonstrated a significant increase in patients with AP versus without AP from H0 to H120. Among the three biomarkers, PCT showed the earliest change. ROC-AUC values were poor for all three biomarkers. Best ROC-AUC values for diagnosing AP were for CRP at H24 [0.73 (95%CI 0.61-0.84)] and PCT at H48 [0.73 (95%CI 0.61-0.84)]. LR+ was best for PCT at H24 (3.5) and LR- for CRP and WBC at H24 (0.4 and 0.4, respectively).

CONCLUSIONS

Early and repeated assays of PCT, CRP, and WBC demonstrated significant increases in all three biomarkers in patients with versus without AP. All three biomarkers had poor diagnostic performance for ruling out AP. Whereas PCT had the fastest kinetics, PCT assays within 48 h after ICU admission do not help to diagnose AP in ICU patients with coma.

Influence of Single-Dose Antibiotic Prophylaxis for Early-Onset Pneumonia in High-Risk Intubated Patients

BACKGROUND

Early-onset pneumonia (EOP) after endotracheal intubation is common among critically ill patients with a neurologic injury and is associated with worse clinical outcomes.

METHODS

This retrospective cohort study observed outcomes pre- and post-implementation of an EOP prophylaxis protocol which involved the administration of a single dose of ceftriaxone 2 g around the time of intubation. The study included patients ≥ 18 years who were admitted to the University of North Carolina Medical Center (UNCMC) neuroscience intensive care unit (NSICU) between April 1, 2014, and October 26, 2016, and intubated for ≥ 72 h.

RESULTS

Among the 172 patients included, use of an EOP prophylaxis protocol resulted in a significant reduction in the rate of microbiologically confirmed EOP compared to those without prophylaxis (7.4 vs 19.8%, p = 0.026). However, EOP prophylaxis did not decrease the combined incidence of microbiologically confirmed or clinically suspected EOP (32.2 vs 37.4%, p = 0.523). No difference in the rate of late-onset pneumonia (34.6 vs 26.4%, p = 0.25) or virulent organism growth (19.8 vs 14.3%, p = 0.416) was observed. No difference was observed in the duration of intubation, duration of intensive care unit (ICU) stay, duration of hospitalization, or ICU antibiotic days within 30 days of intubation. In hospital mortality was found to be higher in those who received EOP prophylaxis compared to those who did not receive prophylaxis (45.7 vs 29.7%, p = 0.04).

CONCLUSIONS

The administration of a single antibiotic dose following intubation may reduce the incidence of microbiologically confirmed EOP in patients with neurologic injury who are intubated ≥ 72 h. A prophylaxis strategy does not appear to increase the rate of virulent organism growth or the rate of late-onset pneumonia. However, this practice is not associated with a decrease in days of antibiotic use in the ICU or any clinical outcomes benefit.

Infections after a traumatic brain injury: The complex interplay between the immune and neurological systems

Traumatic brain injury (TBI) is a serious global health issue, being the leading cause of death and disability for individuals under the age of 45, and one of the largest causes of global neurological disability. In addition to the brain injury itself, it is increasingly appreciated that a TBI may also alter the systemic immune response in a way that renders TBI patients more vulnerable to infections in the acute post-injury period. Such infections pose an additional challenge to the patient, increasing rates of mortality and morbidity, and worsening neurological outcomes. Hospitalization, surgical interventions, and a state of immunosuppression induced by injury to the central nervous system (CNS), may all contribute to the high rate of infections seen in the population with TBI. Ongoing research to better understand the immunomodulators that underlie TBI-induced immunosuppression may aid in the development of effective therapeutic strategies to improve the recovery trajectory for patients. This review first describes the clinical scenario, posing the question of whether TBI patients are more susceptible to infections such as pneumonia, and if so, why? We then consider how cross-talk between the injured brain and the systemic immune system occurs, and further, how the additional immune challenge of an acquired infection can contribute to ongoing neuroinflammation and neurodegeneration after a TBI. Experimental models combining TBI with infection are discussed, as well as current treatment options available for this double-barreled insult. The aims of this review are to summarize current understanding of the bidirectional relationship between the CNS and the immune system when faced with a mechanical trauma combined with a concomitant infection, and to highlight key outstanding questions that remain in the field.

Pneumonia in acute ischemic stroke patients requiring invasive ventilation: Impact on short and long-term outcomes

OBJECTIVES

To describe the epidemiology and prognostic impact of pneumonia in acute ischemic stroke patients requiring invasive mechanical ventilation.

METHODS

Retrospective analysis from a prospective multicenter cohort study of critically ill patients with acute ischemic stroke requiring invasive mechanical ventilation at admission. Impact of pneumonia was investigated using Cox regression for 1-year mortality, and competing risk survival models for ICU mortality censored at 30-days.

RESULTS

We included 195 patients. Stroke was supratentorial in 62% and 64% of patients had a Glasgow coma scale score <8 on admission. Mortality at day-30 and 1 year were 56%, and 70%, respectively. Post-stroke pneumonia was identified in 78 (40%) patients, of which 46/78 (59%) episodes were present at ICU admission. Post-stroke pneumonia was associated with an increase in 1-year mortality (adjusted HR 1.49, 95%CI [1.01-2.20]). Post-stroke pneumonia was not associated with ICU mortality but was associated with a 1.6-fold increase in ICU length of stay (CSHR 0.62 [0.39-0.99], p = 0.06).

CONCLUSIONS

In ischemic stroke patients requiring invasive ventilation, pneumonia occurred in 40% of cases and was associated with a 49% increase in 1-year mortality. Post-stroke pneumonia did not impact day-30 mortality but increased ICU length of stay.

Management of Ventilator-Associated Pneumonia: Guidelines

Two recent major guidelines on diagnosis and treatment of ventilator-associated pneumonia (VAP) recommend consideration of local antibiotic resistance patterns and individual patient risks for resistant pathogens when formulating an initial empiric antibiotic regimen. One recommends against invasive diagnostic techniques with quantitative cultures to determine the cause of VAP; the other recommends either invasive or noninvasive techniques. Both guidelines recommend short-course therapy be used for most patients with VAP. Although neither guideline recommends use of procalcitonin as an adjunct to clinical judgment when diagnosing VAP, they differ with respect to use of serial procalcitonin to shorten the length of antibiotic treatment.

Impact of a Quality Improvement Program on the Neurological Outcome of Patients with Traumatic Spinal Cord Injury: A Before-After Mono-Centric Study

Spinal cord injury (SCI) is a major cause of severe disability. This study aims to assess the effectiveness of a quality improvement program on neurological recovery after SCI. Before-after study during two phases was done in one intensive care unit in a university hospital. The quality improvement project comprised protective mechanical ventilation, early tracheostomy in anatomical injury above the sixth cervical vertebra, early enteral nutrition, early mobilization, and active perineal care in adult SCI patients. The primary endpoint was the difference between the American Spinal Injury Association (ASIA) motor score between discharge and intensive care unit (ICU) admission (Delta ASIA). Fifty-seven and 60 patients were included in the control and in the intervention period respectively. The ASIA motor score upon ICU admission was 16 (7-37) before and 11 (2-30) after the implementation (p = 0.30). The implementation phase was associated with lower tidal volumes (p < 0.001), higher positive end-expiratory pressure (p < 0.001), earlier tracheostomy (p = 0.01), earlier enteral nutrition initiation (p < 0.05), earlier mobilization (p < 0.05), and more active perineal care (p < 0.05). The Delta ASIA was +16 [4-32] after versus +6 [0-14] before the intervention (p < 0.05). After adjustment for potential cofounders, the intervention phase was significantly associated with higher Delta ASIA (β coefficient, 11.4; CI₉₅ [1.9-21]; p = 0.01) in multi-variable analysis. No secular time trend unrelated to the intervention was highlighted. One year after trauma, the Delta ASIA was higher in the intervention period than in the control period (+34 [15-60] vs. +11 [0-33]; p < 0.05). After adjustment on potential confounders, an early in-ICU rehabilitation program in SCI patients was associated with higher neurological score upon ICU discharge.

Risk factors for early-onset ventilator-associated pneumonia in aneurysmal subarachnoid hemorrhage patients

This study aimed to investigate the risk factors related to ventilator-acquired pneumonia (VAP) in aneurysmal subarachnoid hemorrhage (SAH) patients. From January 2011 to December 2015, a single-center retrospective study including 200 SAH patients requiring mechanical ventilation (MV) ≥48 h was performed. The clinical data of these patients were collected and analyzed. The age range of the patients were 41-63 and 72 (36%) were male. The Glasgow coma scale score range was 5-15 and the Simplified Acute Physiology Score II range was 31-52. One hundred and forty-eight (74%) patients had a World Federation of Neurosurgeons (WNFS) score ≥III. Aneurysm was secured with an endovascular coiling procedure in 168 (84%) patients and 94 (47%) patients presented VAP. Male gender (OR=2.25, 95%CI=1.15-4.45), use of mannitol (OR=3.02, 95%CI=1.53-5.94) and enteral feeding above 20 kcal·kg-1·day-1 (OR=2.90, 95%CI=1.26-6.67) after day 7 were independent factors for VAP. Patients with early-onset VAP had a longer duration of sedation (P=0.03), MV (P=0.001) and ICU length of stay (P=0.003) and a worse Glasgow Outcome Scale score (P<0.001), but did not have a higher death rate.

Respiratory Management in Patients with Severe Brain Injury

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2018. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2018 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901 .

World-Wide Variation in Incidence of Staphylococcus aureus Associated Ventilator-Associated Pneumonia: A Meta-Regression

Staphylococcus aureus (S. aureus) is a common Ventilator-Associated Pneumonia (VAP) isolate. The objective here is to define the extent and possible reasons for geographic variation in the incidences of S. aureus-associated VAP, MRSA-VAP and overall VAP. A meta-regression model of S. aureus-associated VAP incidence per 1000 Mechanical Ventilation Days (MVD) was undertaken using random effects methods among publications obtained from a search of the English language literature. This model incorporated group level factors such as admission to a trauma ICU, year of publication and use of bronchoscopic sampling towards VAP diagnosis. The search identified 133 publications from seven worldwide regions published over three decades. The summary S. aureus-associated VAP incidence was 4.5 (3.9–5.3) per 1000 MVD. The highest S. aureus-associated VAP incidence is amongst reports from the Mediterranean (mean; 95% confidence interval; 6.1; 4.1–8.5) versus that from Asian ICUs (2.1; 1.5–3.0). The incidence of S. aureus-associated VAP varies by up to three-fold (for the lowest versus highest incidence) among seven geographic regions worldwide, whereas the incidence of VAP varies by less than two-fold. Admission to a trauma unit is the most important group level correlate for S. aureus-associated VAP.

Unusually High Incidences of Staphylococcus aureus Infection within Studies of Ventilator Associated Pneumonia Prevention Using Topical Antibiotics: Benchmarking the Evidence Base

Selective digestive decontamination (SDD, topical antibiotic regimens applied to the respiratory tract) appears effective for preventing ventilator associated pneumonia (VAP) in intensive care unit (ICU) patients. However, potential contextual effects of SDD on Staphylococcus aureus infections in the ICU remain unclear. The S. aureus ventilator associated pneumonia (S. aureus VAP), VAP overall and S. aureus bacteremia incidences within component (control and intervention) groups within 27 SDD studies were benchmarked against 115 observational groups. Component groups from 66 studies of various interventions other than SDD provided additional points of reference. In 27 SDD study control groups, the mean S. aureus VAP incidence is 9.6% (95% CI; 6.9–13.2) versus a benchmark derived from 115 observational groups being 4.8% (95% CI; 4.2–5.6). In nine SDD study control groups the mean S. aureus bacteremia incidence is 3.8% (95% CI; 2.1–5.7) versus a benchmark derived from 10 observational groups being 2.1% (95% CI; 1.1–4.1). The incidences of S. aureus VAP and S. aureus bacteremia within the control groups of SDD studies are each higher than literature derived benchmarks. Paradoxically, within the SDD intervention groups, the incidences of both S. aureus VAP and VAP overall are more similar to the benchmarks.

Systemic antibiotics for preventing ventilator-associated pneumonia in comatose patients: a systematic review and meta-analysis

BACKGROUND

Early-onset ventilator-associated pneumonia (EO-VAP) is the leading cause of morbidity and mortality in comatose patients. However, VAP prevention bundles focus mainly on late-onset VAP and may be less effective in preventing EO-VAP in comatose patients. Systemic antibiotic administration at the time of intubation may have a role in preventing EO-VAP. Therefore, we evaluated the effectiveness of systemic antibiotic administration in VAP prevention in comatose patients through a systematic review and meta-analysis.

METHODS

We searched for studies published through December 2015 that evaluated systemic antibiotic prophylaxis in comatose patients. Two authors independently selected and evaluated full-length reports of randomized clinical trials or prospective cohorts in patients aged >16 years that evaluated the impact of systemic antibiotics at the time of intubation on EO-VAP compared to placebo or no prophylaxis. The outcome variables were the incidence of EO-VAP, the duration of mechanical ventilation, ICU length of stay, and ICU mortality.

RESULTS

We identified 10,988 citations, yielding 26 articles for further analysis; three studies with 267 patients were finally analyzed. Most patients (n = 135) were comatose due to head trauma. Systemic antibiotic administration was associated with decreased incidence of EO-VAP (RR 0.32; 95% CI 0.19-0.54) and shorter ICU LOS (standardized mean difference -0.32; 95% CI -0.56 to -0.08), but had no effect on mortality (RR 1.03; 95% CI 0.7-1.53) or duration of mechanical ventilation (standardized mean difference -0.16; 95% CI -0.41 to 0.08).

CONCLUSIONS

Antibiotic prophylaxis in comatose patients reduced the incidence of EO-VAP and decreased the ICU stay slightly. Future trials are needed to confirm these results.

Risk factors for ventilator-associated pneumonia among patients undergoing major oncological surgery for head and neck cancer

Patients undergoing major oncological surgery for head and neck cancer (SHNC) have a particularly high risk of nosocomial infections. We aimed to identify risk factors for ventilator-associated pneumonia (VAP) in patients undergoing SHNC. The study included 465 patients who underwent SHNC between June 2011 and June 2014. The rate of VAP, risk factors for VAP, and biological aspects of VAP were retrospectively evaluated. The incidence of VAP was 19.6% (n = 95) in patients who required more than 48 h of mechanical ventilation. Staphylococcus (37.7%), Enterobacteriaceae (32.1%), Pseudomonas (20.8%), and Haemophilus (16.9%) were the major bacterial species that caused VAP. The independent risk factors for VAP were advanced age, current smoking status, chronic obstructive pulmonary disease, and a higher simplified acute physiology score system II upon admission. Tracheostomy was an independent protective factor for VAP. The median length of stay in the ICU for patients who did or did not develop VAP was 8.0 and 6.5 days, respectively (P = 0.006). Mortality among patients who did or did not develop VAP was 16.8% and 8.4%, respectively (P < 0.001). The potential economic impact of VAP was high because of the significantly extended duration of ventilation. A predictive regression model was developed with a sensitivity of 95.3% and a specificity of 69.4%. VAP is common in patients who are undergoing SHNC and who require more than 48 h of mechanical ventilation. Therefore, innovative preventive measures should be developed and applied in this high-risk population.

Guidelines for the Management of Severe Traumatic Brain Injury, Fourth Edition

The scope and purpose of this work is 2-fold: to synthesize the available evidence and to translate it into recommendations. This document provides recommendations only when there is evidence to support them. As such, they do not constitute a complete protocol for clinical use. Our intention is that these recommendations be used by others to develop treatment protocols, which necessarily need to incorporate consensus and clinical judgment in areas where current evidence is lacking or insufficient. We think it is important to have evidence-based recommendations to clarify what aspects of practice currently can and cannot be supported by evidence, to encourage use of evidence-based treatments that exist, and to encourage creativity in treatment and research in areas where evidence does not exist. The communities of neurosurgery and neuro-intensive care have been early pioneers and supporters of evidence-based medicine and plan to continue in this endeavor. The complete guideline document, which summarizes and evaluates the literature for each topic, and supplemental appendices (A-I) are available online at https://www.braintrauma.org/coma/guidelines.

Twenty-Eight-Day Mortality of Blunt Traumatic Brain Injury and Co-Injuries Requiring Mechanical Ventilation

OBJECTIVE

This paper aims to assess the impact of co-injuries and consequent emergency surgical interventions and nosocomial pneumonia on the 28-day mortality of patients with severe traumatic brain injuries (TBIs).

SUBJECTS AND METHODS

One hundred and seventy-seven patients with TBI admitted to the emergency trauma intensive care unit at the Clinical Center of Serbia for more than 48 h were studied over a 1-year period. On admission, the Glasgow Coma Scale (GCS), Injury Severity Score (ISS) and Acute Physiology and Chronic Health Evaluation II score (APACHE II) were calculated. At admission, an isolated TBI was recorded in 45 of the patients, while 44 had three or more co-injuries.

RESULTS

Of the 177 patients, 78 (44.1%) died by the end of the 28-day follow-up period. They had a significantly higher ISS score (25 vs. 20; p = 0.024) and more severe head (p = 0.034) and chest (p = 0.013) injuries compared to those who survived. Nonsurvivors had spent more days on mechanical ventilation (9.5 vs. 8; p = 0.041) and had a significantly higher incidence of ventilator-associated pneumonia (VAP) than survivors (67.9 vs. 40.4%; p < 0.001). A high Rotterdam CT score (OR 2.062; p < 0.001) and a high APACHE II score (OR 1.219; p < 0.001) were identified as independent predictors of early TBI-related mortality.

CONCLUSION

Patients who had TBI with a high Rotterdam score and a high APACHE II score were at higher risk of 28-day mortality. VAP was a very common complication of TBI and was associated with an early death and higher mortality in the subgroup of patients with a GCS ≤8.

Ventilator-Associated Pneumonia in Pediatric Traumatic Brain Injury

Ventilator-associated pneumonia (VAP) is a common occurrence among intubated pediatric traumatic brain injury (TBI) patients. However, little is known about the epidemiology, risk factors, and microbiology of VAP in pediatric TBI. We reviewed a cohort of 119 pediatric moderate-to-severe TBI patients and identified 42 with VAP by positive protected bronchial brush specimens. Location of intubation, severity of injury, and antibiotic administration within 2 days after injury were not associated with VAP. Most treatments for elevated intracranial pressure were associated with increased risk of VAP; however, in a multi-variable analysis barbiturate coma (hazard ratio [HR], 3.2; 95% confidence interval [CI] 1.4-7.3), neuromuscular blockade (NMBA; HR, 3.4; 95% CI 1.6-7.3), and use of a cooling blanket for euthermia (HR 2.4; 95% CI 1.1-5.5) remained independently associated with VAP. Most VAP (55%) occurred prior to hospital Day 4 and only 7% developed VAP after Day 7. Methicillin-sensitive Staphylococcus aureus (34%), Haemophilus influenzae (22%), and Streptococcus pneumoniae (15%) were the most common organisms, comprising 71% of isolated pathogens (36% of infections were polymicrobial). Patients with VAP had significantly longer intensive care unit and hospital stays, as well as increased risk of chronic care needs after discharge, but not mortality. VAP is a common occurrence in pediatric TBI patients, and early empiric therapy for patients requiring barbiturate infusion, NMBA, or use of a cooling blanket could mitigate morbidity.

Phenotype and functions of B cells in patients with acute brain injuries

BACKGROUND

Brain injuries (BI) induce a state of systemic immunosuppression, leading to a high risk of pneumonia. In this pilot study, we investigated the status of B cell compartment in BI patients.

METHODS

A prospective observational study was performed in 2 intensive care units in a university hospital. Blood samples were collected in 14 patients at day 1 and day 7 after acute BI. The phenotype and the ability of B cells to secrete IL-10 were compared to 11 healthy volunteers (HV).

RESULTS

Among the circulating lymphocytes, the frequency of B cells was significantly higher in BI patients compared to HV (p<0.001). B cells from BI patients displayed an activated profil on day 7 after BI, reflected by a significantly higher proportion of CD27(+) memory (p=0.01) and CD27(+) IgD(-) switched memory B cells (p=0.02), as well as a significantly higher blood level of IgA (p=0.001) and IgM (p<0.001) as compared to day 1. The frequency of IL-10 secreting B cells (IL-10(+) B cells) on day 1 and day 7 was significantly lower in BI patients compared to HV (p<0.05). Interestingly, we observed that all BI patients with high frequency of IL-10(+) B cells on day 1 displayed an episode of pneumonia, and had a longer duration of mechanical ventilation and ICU stay compared to BI patients with low proportion of IL-10(+) B cells.

CONCLUSION

This study provides an extensive description of the phenotype and function of B cells in BI patients. Our results suggest that IL-10(+) B cells could play a major role in immunosuppression after BI.

Brain-lung crosstalk: Implications for neurocritical care patients

Major pulmonary disorders may occur after brain injuries as ventilator-associated pneumonia, acute respiratory distress syndrome or neurogenic pulmonary edema. They are key points for the management of brain-injured patients because respiratory failure and mechanical ventilation seem to be a risk factor for increased mortality, poor neurological outcome and longer intensive care unit or hospital length of stay. Brain and lung strongly interact via complex pathways from the brain to the lung but also from the lung to the brain. Several hypotheses have been proposed with a particular interest for the recently described “double hit” model. Ventilator setting in brain-injured patients with lung injuries has been poorly studied and intensivists are often fearful to use some parts of protective ventilation in patients with brain injury. This review aims to describe the epidemiology and pathophysiology of lung injuries in brain-injured patients, but also the impact of different modalities of mechanical ventilation on the brain in the context of acute brain injury.

Mechanisms and treatment of post-traumatic liver injury

Multiple organ failure is the leading cause of death in patients with severe multiple trauma in the early stage after injury. Hepatic insufficiency is common in intensive care unit (ICU), and about 27% of the patients with severe trauma suffer hepatic failure. However, the pathogenesis of traumatic liver damage is complicated due to the following main reasons: liver trauma, ischemia-reperfusion injury, severe sepsis, danger associated molecular patterns and so on. Clinically, trauma-induced liver injury can be managed conservatively or surgically, therefore, clarifying the mechanisms of traumatic liver damage, finding a new therapeutic target and improving its diagnosis and treatment are very important. This paper reviews the mechanism of post-traumatic liver injury and its diagnosis and treatment.

Computed tomography pulmonary angiography: more than a screening tool for pulmonary embolus

BACKGROUND

Traumatically injured patients have multiple causes for acute respiratory decompensation. We reviewed the use of computed tomography pulmonary angiography (CTPA) in critically injured patients to evaluate the results and impact on patient care.

METHODS

The charts of trauma patients (age >16 years) admitted to our intensive care unit for greater than 48 hours, who underwent CTPA for acute respiratory decompensation, were reviewed to determine the results of these studies and the effect on patient care.

RESULTS

We identified 188 patients who underwent CTPA for acute physiologic changes. Pertinent clinical finding were identified in 95% of studies and included atelectasis/collapse (56%), pleural effusion (18%), pneumonia (15%), and pulmonary embolus (18%). These results prompted interventions designed to improve patient outcome. The most frequent interventions were modifications of ventilator therapy (52%), antibiotic therapy (28%), mini-bronchoalveolar lavage (15%), or bronchoscopy (15%). Diagnostic agreement between chest x-ray and CTPA was poor to moderate (κ = 0.013-0.512).

CONCLUSIONS

Computed tomography pulmonary angiography is valuable in the evaluation of cardiopulmonary deterioration in critically ill traumatically injured patients. Computed tomography pulmonary angiography offers the ability to identify causes of acute physiologic changes not detected using standard chest x-ray. The results of these studies provide insight into the underlying pathophysiology and offer an opportunity to direct subsequent patient care.

Pulse pressure variations to guide fluid therapy in donors: a multicentric echocardiographic observational study

PURPOSE

Preload responsiveness parameters could be useful in the hemodynamic management of septic shock.

METHODS

A multicentric prospective echocardiographic observational study was conducted from March 2009 to August 2011. Clinically brain-dead subjects were included. Pulse pressure variations (ΔPPs) were recorded. Cardiac index, variation of the maximum flow velocity of aortic systolic blood flow, and right ventricular function parameters were evaluated via transthoracic echocardiography. Fluid responsiveness was defined by at least 15% cardiac index increase, 30 minutes after a 500-mL colloid solution infusion. The number of organs harvested was recorded.

RESULTS

Twenty-five subjects were included. Pulse pressure variation could not discriminate responders (n=15) from nonresponders (n=10). The best ΔPP threshold (20%) could discriminate responders with a sensitivity of 100% and a specificity of 40%. Variation of the maximum flow velocity of aortic systolic blood flow, tricuspid annular plane systolic excursion, and right ventricle dilation could not discriminate responders from nonresponders. Eighteen subjects underwent organ harvesting. The number of organs harvested was higher in responders (3.5 [3-5]) than in nonresponders (2.5 [2-3]; P=.03).

CONCLUSIONS

A ΔPP threshold of 13% is insufficient to guide volume expansion in donors. The best threshold is 20%. Fluid responsiveness monitoring could enhance organ harvesting.

Implementation of an evidence-based extubation readiness bundle in 499 brain-injured patients. a before-after evaluation of a quality improvement project

RATIONALE

Mechanical ventilation is associated with morbidity in patients with brain injury.

OBJECTIVES

This study aims to assess the effectiveness of an extubation readiness bundle to decrease ventilator time in patients with brain injury.

METHODS

Before-after design in two intensive care units (ICUs) in one university hospital. Brain-injured patients ventilated more than 24 hours were evaluated during two phases (a 3-yr control phase followed by a 22-mo intervention phase). Bundle components were protective ventilation, early enteral nutrition, standardization of antibiotherapy for hospital-acquired pneumonia, and systematic approach to extubation. The primary endpoint was the duration of mechanical ventilation.

MEASUREMENTS AND MAIN RESULTS

A total of 299 and 200 patients, respectively, were analyzed in the control and the intervention phases of this before-after study. The intervention phase was associated with lower tidal volume (P < 0.01), higher positive end-expiratory pressure (P < 0.01), and higher enteral intake in the first 7 days (P = 0.01). The duration of mechanical ventilation was 14.9 ± 11.7 days in the control phase and 12.6 ± 10.3 days in the intervention phase (P = 0.02). The hazard ratio for extubation was 1.28 (95% confidence interval [CI], 1.04-1.57; P = 0.02) in the intervention phase. Adjusted hazard ratio was 1.40 (95% CI, 1.12-1.76; P < 0.01) in multivariate analysis and 1.34 (95% CI, 1.03-1.74; P = 0.02) in propensity score-adjusted analysis. ICU-free days at Day 90 increased from 50 ± 33 in the control phase to 57 ± 29 in the intervention phase (P < 0.01). Mortality at Day 90 was 28.4% in the control phase and 23.5% in the intervention phase (P = 0.22).

CONCLUSIONS

The implementation of an evidence-based extubation readiness bundle was associated with a reduction in the duration of ventilation in patients with brain injury.

High incidence of post-injury pneumonia in intensive care-treated trauma patients

INTRODUCTION

Trauma patients are susceptible to post-injury infections. We investigated the incidence, as well as risk factors for development of pneumonia in intensive care unit (ICU)-treated trauma patients. In addition, we report pathogens identified in patients that developed pneumonia.

METHODS

The study cohort consisted of 322 trauma patients admitted to the ICU at a level-one trauma centre following initial resuscitation. Patients 15 years or older with an ICU stay of more than 24 h were included. We investigated pre-hospital and hospital parameters during the first 24 h after admission and their possible association with pneumonia within 10 days of ICU admission.

RESULTS

Majority of the patients were male (78%) and the median age was 41 years. The overall degree of injury was high with a median Injury Severity Score (ISS) of 24. Overall 30-day mortality was 9%. Eighty-five (26%) patients developed pneumonia during their first 10 days in the ICU. Univariate logistic regression revealed that intubation in the field, shock, Glasgow Coma Scale (GCS) 3-8, major surgery within 24 h after admission, massive transfusion and ISS > 24 were all risk factors for subsequent development of pneumonia. In the multivariable model, only GCS 3-8 was identified as an independent risk factor. In 42 out of the 85 cases of pneumonia, the diagnosis was defined by significant growth of at least one pathogen where Enterobacteriaceae and Staphylococcus aureus were the most common.

CONCLUSIONS

Pneumonia is a common complication among ICU-treated trauma patients. Reduced consciousness is an independent risk factor for development of pneumonia after severe injury.

Balanced versus chloride-rich solutions for fluid resuscitation in brain-injured patients: a randomised double-blind pilot study

INTRODUCTION

We sought to investigate whether the use of balanced solutions reduces the incidence of hyperchloraemic acidosis without increasing the risk for intracranial hypertension in patients with severe brain injury.

METHODS

We conducted a single-centre, two-arm, randomised, double-blind, pilot controlled trial in Nantes, France. Patients with severe traumatic brain injury (Glasgow Coma Scale score ≤8) or subarachnoid haemorrhage (World Federation of Neurosurgical Society grade III or higher) who were mechanically ventilated were randomised within the first 12 hours after brain injury to receive either isotonic balanced solutions (crystalloid and hydroxyethyl starch; balanced group) or isotonic sodium chloride solutions (crystalloid and hydroxyethyl starch; saline group) for 48 hours. The primary endpoint was the occurrence of hyperchloraemic metabolic acidosis within 48 hours.

RESULTS

Forty-two patients were included, of whom one patient in each group was excluded (one consent withdrawn and one use of forbidden therapy). Nineteen patients (95%) in the saline group and thirteen (65%) in the balanced group presented with hyperchloraemic acidosis within the first 48 hours (hazard ratio = 0.28, 95% confidence interval [CI] = 0.11 to 0.70; P = 0.006). In the saline group, pH (P = .004) and strong ion deficit (P = 0.047) were lower and chloraemia was higher (P = 0.002) than in the balanced group. Intracranial pressure was not different between the study groups (mean difference 4 mmHg [-1;8]; P = 0.088). Seven patients (35%) in the saline group and eight (40%) in the balanced group developed intracranial hypertension (P = 0.744). Three patients (14%) in the saline group and five (25%) in the balanced group died (P = 0.387).

CONCLUSIONS

This study provides evidence that balanced solutions reduce the incidence of hyperchloraemic acidosis in brain-injured patients compared to saline solutions. Even if the study was not powered sufficiently for this endpoint, intracranial pressure did not appear different between groups.

TRIAL REGISTRATION

EudraCT 2008-004153-15 and NCT00847977.

[Nutritional therapy in traumatic brain injury : Update 2012]

Severe traumatic brain injury ranks among the most common causes of death in young adults in western countries. Severe traumatic brain injury is typically followed by a pronounced pathophysiological cascade that accounts for many deaths. The aim of intensive care medicine after traumatic brain injury is to minimize and to control the consequences of this potentially fatal cascade. The avoidance of hypoxemia, arterial hypotension, intracranial hypertension, hyperthermia, hyperglycemia, hypoglycemia and thromboembolic complications is essential in preventing this cascade. The effect of nutrition has been rather underestimated as a means of improving the outcome after traumatic brain injury. Nutrition should be started within the first 24 h after trauma. Enteral, wherever applicable, should be the route of administration of nutrition. Enteral administration of the whole calculated calorie requirement on day 1 after trauma, if possible, lowers the infection and overall complication rates. The present review gives an update of a practical approach to nutrition in traumatic brain injury.

Status epilepticus: a review, with emphasis on refractory cases

Status epilepticus is among the most dramatic of clinical presentations encountered by emergency room physicians, neurologists, neurosurgeons and intensivists. While progress in its management has been aided significantly with an increasing number of effective treatment options, improved diagnostic methods and more effective monitoring, poor outcomes and diagnostic failures are still frequently encountered. Refractory cases still carry significant morbidity and mortality rates, including poor cognitive outcomes. This review discusses basic pathophysiology and management of status epilepticus, neuroimaging findings, the role of continuous electroencephalogram monitoring and nonconvulsive status epilepticusas well as recent developments in treatment options for refractory cases.

Etomidate increases susceptibility to pneumonia in trauma patients

PURPOSE

To investigate the impact of etomidate on the rate of hospital-acquired pneumonia (HAP) in trauma patients and the effects of hydrocortisone in etomidate-treated patients.

METHODS

This was a sub-study of the HYPOLYTE multi-centre, randomized, double-blind, placebo-controlled trial of hydrocortisone in trauma patients (NCT00563303). Inclusion criterion was trauma patient with mechanical ventilation (MV) of ≥48 h. The use of etomidate was prospectively collected. Endpoints were the results of the cosyntropin test and rate of HAP on day 28 of follow-up.

RESULTS

Of the 149 patients enrolled in the study, 95 (64 %) received etomidate within 36 h prior to inclusion. 79 (83 %) of 95 patients receiving etomidate and 34 of the 54 (63 %) not receiving etomidate had corticosteroid insufficiency (p = 0.006). The administration of etomidate did not alter basal cortisolemia (p = 0.73), but it did decrease the delta of cortisolemia at 60 min (p = 0.007). There was a correlation between time from etomidate injection to inclusion in the study and sensitivity to corticotropin (R (2) = 0.19; p = 0.001). Forty-nine (51.6 %) patients with etomidate and 16 (29.6 %) patients without etomidate developed HAP by day 28 (p = 0.009). Etomidate was associated with HAP on day 28 in the multivariate analysis (hazard ratio 2.48; 95 % confidence interval 1.19-5.18; p = 0.016). Duration of MV with or without etomidate was not significantly different (p = 0.278). Among etomidate-exposed patients, 18 (40 %) treated with hydrocortisone developed HAP compared with 31 (62 %) treated with placebo (p = 0.032). Etomidate-exposed patients treated with hydrocortisone had fewer ventilator days (p < 0.001).

CONCLUSIONS

Among the patients enrolled in the study, etomidate did not alter basal cortisolemia, but it did decrease reactivity to corticotropin. We suggest that in trauma patients, etomidate is an independent risk factor for HAP and that the administration of hydrocortisone should be considered after etomidate use.