Infections in patients with traumatic brain injury who undergo neurosurgery

Decompressive craniectomy incisions: all roads lead to bone

INTRODUCTION

Decompressive craniectomy and craniotomy are among the most common procedures in Neurosurgery. In recent years, increased attention has focused on the relationships between incision type, extent of decompression, vascular supply to the scalp, cosmetic outcomes, and complications. Here, we review the current literature on scalp incisions for large unilateral front-temporo-parietal craniotomies and craniectomies.

METHODS

Publications in the past 50 years on scalp incisions used for front-temporo-parietal craniectomies/craniotomies were reviewed. Only full texts were considered in the final analysis. A total of 27 studies that met the criteria were considered for the final manuscript. PRISMA guidelines were adopted for this study.

RESULTS

Five main incision types have been described. In addition to the question mark incision, other common incisions include the T-Kempe, developed to obtain wide access to the skull, the retroauricular incision, designed to spare the occipital branch, as well as the N-shaped and cloverleaf incisions which integrate with pterional approaches. Advantages and drawbacks, integration with existing incisions, relationships with the main arteries, cosmetic outcomes, and risks of wound complications including dehiscence, necrosis, and infection were assessed.

DISCUSSION

The reverse-question mark incision, despite being a mainstay of trauma neurosurgery, can place the vascular supply to the scalp at risk and favor wound dehiscence and infection. Several incisions, such as the T-Kempe, retroauricular, N-shaped, and cloverleaf approaches have been developed to preserve the main vessels supplying the scalp. Incision choice needs to be carefully weighted based on the patient's anatomy, position and size of main vessels, risk of wound dehiscence, and desired volume of decompression.

Pulmonary Effects of Traumatic Brain Injury in Mice: A Gene Set Enrichment Analysis

Acute lung injury occurs in 20-25% of cases following traumatic brain injury (TBI). We investigated changes in lung transcriptome expression post-TBI using animal models and bioinformatics. Employing unilateral controlled cortical impact for TBI, we conducted microarray analysis after lung acquisition, followed by gene set enrichment analysis of differentially expressed genes. Our findings indicate significant upregulation of inflammation-related genes and downregulation of nervous system genes. There was enhanced infiltration of adaptive immune cells, evidenced by positive enrichment in Lung-Th1, CD4, and CD8 T cells. Analysis using the Tabula Sapiens database revealed enrichment in lung-adventitial cells, pericytes, myofibroblasts, and fibroblasts, indicating potential effects on lung vasculature and fibrosis. Gene set enrichment analysis linked TBI to lung diseases, notably idiopathic pulmonary hypertension. A Venn diagram overlap analysis identified a common set of 20 genes, with FOSL2 showing the most significant fold change. Additionally, we observed a significant increase in ADRA1A→IL6 production post-TBI using the L1000 library. Our study highlights the impact of brain trauma on lung injury, revealing crucial gene expression changes related to immune cell infiltration, cytokine production, and potential alterations in lung vasculature and fibrosis, along with a specific spectrum of disease influence.

The microbiological profile of isolates recovered from ICU patients with traumatic brain injuries at a tertiary care center, Southern Region, Saudi Arabia

INTRODUCTION

Traumatic head injury THI is a Neurosurgical condition in which brain function is interrupted as a result of blunt (motor vehicle accidents MVA, falls, and assaults) or penetrating trauma. Nearly half of all injuries are caused by head trauma. Head traumas are a leading cause of death and organ loss in young people, where this population accounts for the vast majority of TBI patients.

METHODOLOGY

This retrospective cohort study was conducted at Asir Central Hospital, KSA with data from 2015 to 2019. Records of bacterial cultures and outcomes such as length of stay in the hospital were analyzed. In addition, treatment outcomes were also analyzed.

RESULTS

A total of 300 ICU patient samples (69 patients) were included. Patients' ages ranged from 13 to 87 years with a mean age of 32.4 ± 17.5 years old. The most frequently reported diagnosis was RTA (71 %), followed by SDH (11.6 %), The most isolated organisms from the recovered samples were Klebsiella pneumoniae (27 %), followed by Pseudomonas aeruginosa (14.7 %). Regarding susceptibility, Tigecycline was the most sensitive (44 %), followed by Gentamicin (43.3 %). A total of 36 (52.2 %) patients stayed for less than one month, 24 (34.8 %) stayed for 1-3 months, and 7 (10.1 %) stayed for 3-6 months. The mortality rate in our study population was (40.6 %) as 28 patients died.

CONCLUSION

The prevalence of pathogens in TBI needs to be determined in different institutions for the establishment of effective empiric antibiotic treatment following infections in traumatic brain injuries. This will ultimately help to improve treatment outcomes. In neurosurgical patients undergoing cranial procedures after trauma, a hospital-standardized antibiotic policy is effective in achieving low rates of bacterial infections especially MDR infections.

Time to Follow Commands in Severe Traumatic Brain Injury Survivors With Favorable Recovery at 2 Years

BACKGROUND

The recovery of severe traumatic brain injury (TBI) survivors with long-term favorable outlook is understudied. Time to follow commands varies widely in this patient population but has important clinical implications.

OBJECTIVE

To (1) evaluate time to follow commands in severe patients with TBI with favorable outcomes, (2) characterize their trajectory of recovery, and (3) identify predictors associated with delayed cognitive improvement.

METHODS

Participants were recruited prospectively at a Level I trauma center through the Brain Trauma Research Center from 2003 to 2018. Inclusion criteria were age 16 to 80 years, Glasgow Coma Scale score ≤8 and motor score <6, and Glasgow Outcome Scale-Extended measure ≥4 at 2 years postinjury.

RESULTS

In 580 patients, there were 229 (39.5%) deaths and 140 (24.1%) patients had favorable outcomes at 2 years. The mean age was 33.7 ± 14.5 years, median Glasgow Coma Scale was 7 (IQR 6-7), and median Injury Severity Score was 30 (IQR 26-38). The mean time to follow commands was 12.7 ± 11.8 days. On multivariable linear regression, the presence of diffuse axonal injury (B = 9.2 days [4.8, 13.7], P < .0001) or intraventricular hemorrhage (B = 6.4 days [0.5, 12.3], P < .035) was associated with longer time before following commands and patients who developed nosocomial infections (B = 6.5 days [1.6-11.4], P < .01).

CONCLUSION

In severe TBI survivors with favorable outcomes, time to follow commands varied widely. Most patients began to follow commands within 2 weeks. Evidence of diffuse axonal injury, intraventricular hemorrhage, and infections can delay cognitive improvement in the acute period. Patients make considerable recovery up to 2 years after their injury.

Inflammation and the role of infection: Complications and treatment options following neurotrauma

Traumatic brain injury can have devastating consequences for patients and extended hospital stays and recovery course. Recent data indicate that the initial insult causes profound changes to the immune system and leads to a pro-inflammatory state. This alteration in homeostasis predisposes patients to an increased risk of infection and underlying autoimmune conditions. Increased emphasis has been placed on understanding this process both in the clinical and preclinical literature. This review highlights the intrinsic inflammatory conditions that can occur within the initial hospital stay, discusses long-term immune consequences, highlights emerging treatment options, and delves into important pathways currently being investigated with preclinical models.

The Retroauricular Incision as an Effective and Safe Alternative Incision for Decompressive Hemicraniectomy

BACKGROUND

The reverse question mark (RQM) incision has been traditionally utilized to perform decompressive hemicraniectomies (DHC) to relieve refractory intracranial hypertension. Alternative incisions have been proposed in the literature but have not been compared directly.

OBJECTIVE

To present the retroauricular (RA) incision as an alternative incision that we hypothesize will increase calvarium exposure to maximize the removal of the hemicranium and will decrease wound-related complications compared to the RQM incision.

METHODS

This study is a retrospective review of all DHCs performed at our institution over a span of 34 mo, stratified based on the type of scalp incision. The surface areas of the cranial defects were calculated, normalizing to their respective skull diameters. For those patients surviving beyond 1 wk, complications were examined from both cohorts.

RESULTS

A total of 63 patients in the RQM group and 43 patients in the RA group were included. The average surface area for the RA and RQM incisions was 117.0 and 107.8 cm2 (P = .0009), respectively. The ratio of average defect size to skull size for RA incision was 0.81 compared to 0.77 for the RQM group (P = .0163). Of those who survived beyond 1 wk, the absolute risk for surgical site complications was 14.0% and 8.3% for RQM and RA group (P = .5201), respectively.

CONCLUSION

The RA incision provides a safe and effective alternative incision to the traditional RQM incision used for DHC. This incision affords a potentially larger craniectomy while mitigating postoperative wound complications.

Nosocomial Infections in Patients with Traumatic Brain Injury: A Hospital-Based Study from North India

Background Traumatic brain injury (TBI) is a major global health concern, it being a leading cause of morbidity and mortality in young adults. Infections acquired in the hospital setting are one of many risk factors that are associated with higher mortality in this population. Despite significant impact on the overall outcome, infections in TBI patients are largely understudied and underreported. The purpose of this study was to study the profile of infectious complications in patients with TBI and impact of these infections on the hospital outcome of these patients.

Materials and Methods The medical records of all the patients with a diagnosis of TBI admitted in our hospital from January 2017 to January 2020 were reviewed. They were screened for presence of any predefined infection acquired at any time during their hospital stay. Data regarding demographics, focus of infection, results of various cultures, and hospital outcome was recorded.

Results A total of 60 patients with TBI who had developed nosocomial infections were included in this observational study. Patients were mostly young, with a mean age of 36.6 years. Majority (66.6%) of patients who developed infectious complications had Glasgow coma scale (GCS) score of less than 10. Respiratory tract and urinary tract were the most common sites of infections in these patients. Burkholderia cepecia and Acinetobacter baumannii were the two most common isolated organisms. All-cause mortality in this population was 23.3%.

Conclusions Most TBI patients are young, in their productive period of lives, and do not have major comorbidities. Invariably, they have low GCS scores and encounter a breach of their surface immunity due to catheters, procedures, and intubation. Such patients make an extremely significant impact on hospital resources as well as poor economic outcomes.

Blunt and Penetrating Severe Traumatic Brain Injury

Severe traumatic brain injury is a common problem. Current practices focus on the importance of early resuscitation, transfer to high-volume centers, and provider expertise across multiple specialties. In the emergency department, patients should receive urgent intracranial imaging and consideration for tranexamic acid. Close observation in the intensive care unit environment helps identify problems, such as seizure, intracranial pressure crisis, and injury progression. In addition to traditional neurologic examination, patients benefit from use of intracranial monitors. Monitors gather physiologic data on intracranial and cerebral perfusion pressures to help guide therapy. Brain tissue oxygenation monitoring and cerebromicrodialysis show promise in studies.

A systemic immune challenge to model hospital-acquired infections independently regulates immune responses after pediatric traumatic brain injury

Background

Traumatic brain injury (TBI) is a major cause of disability in young children, yet the factors contributing to poor outcomes in this population are not well understood. TBI patients are highly susceptible to nosocomial infections, which are mostly acquired within the first week of hospitalization, and such infections may modify TBI pathobiology and recovery. In this study, we hypothesized that a peripheral immune challenge such as lipopolysaccharide (LPS)—mimicking a hospital-acquired infection—would worsen outcomes after experimental pediatric TBI, by perpetuating the inflammatory immune response.

Methods

Three-week-old male mice received either a moderate controlled cortical impact or sham surgery, followed by a single LPS dose (1 mg/kg i.p.) or vehicle (0.9% saline) at 4 days post-surgery, then analysis at 5 or 8 days post-injury (i.e., 1 or 4 days post-LPS).

Results

LPS-treated mice exhibited a time-dependent reduction in general activity and social investigation, and increased anxiety, alongside substantial body weight loss, indicating transient sickness behaviors. Spleen-to-body weight ratios were also increased in LPS-treated mice, indicative of persistent activation of adaptive immunity at 4 days post-LPS. TBI + LPS mice showed an impaired trajectory of weight gain post-LPS, reflecting a synergistic effect of TBI and the LPS-induced immune challenge. Flow cytometry analysis demonstrated innate immune cell activation in blood, brain, and spleen post-LPS; however, this was not potentiated by TBI. Cytokine protein levels in serum, and gene expression levels in the brain, were altered in response to LPS but not TBI across the time course. Immunofluorescence analysis of brain sections revealed increased glia reactivity due to injury, but no additive effect of LPS was observed.

Conclusions

Together, we found that a transient, infection-like systemic challenge had widespread effects on the brain and immune system, but these were not synergistic with prior TBI in pediatric mice. These findings provide novel insight into the potential influence of a secondary immune challenge to the injured pediatric brain, with future studies needed to elucidate the chronic effects of this two-hit insult.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02114-1.

Healthcare-Associated Infections in the Neurocritical Care Unit

PURPOSE OF REVIEW

This article summarizes updated data and knowledge on healthcare-associated infections in the neurocritical care unit, with a focus on central nervous system infections and systemic infectious complications in patients with acute brain disease. It also reviews the concept of brain injury-induced immune modulation, an underlying mechanism to explain why the neuro-ICU population is particularly susceptible to infections.

RECENT FINDINGS

Healthcare-associated infections in the neuro-ICU are common: up to 40 % of meningitides in the developed world are now healthcare-associated. The number of gram-negative infections is rising. New diagnostic approaches attempt to aid in the diagnosis of healthcare-associated meningitis and ventriculitis. Healthcare-associated infections in the neurocritical care unit remain a challenge for diagnosis, treatment, and prevention. Gaining a better understanding of at-risk patients and development of preventative strategies will be the goal for future investigation.

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.

Aiming for the target: Mitochondrial drug delivery in traumatic brain injury

Mitochondria are a keystone of neuronal function, serving a dual role as sustainer of life and harbinger of death. While mitochondria are indispensable for energy production, a dysregulated mitochondrial network can spell doom for both neurons and the functions they provide. Traumatic brain injury (TBI) is a complex and biphasic injury, often affecting children and young adults. The primary pathological mechanism of TBI is mechanical, too rapid to be mitigated by anything but prevention. However, the secondary injury of TBI evolves over hours and days after the initial insult providing a window of opportunity for intervention. As a nexus point of both survival and death during this second phase, targeting mitochondrial pathology in TBI has long been an attractive strategy. Often these attempts are mired by efficacy-limiting unintended off-target effects. Specific delivery to and enrichment of therapeutics at their submitochondrial site of action can reduce deleterious effects and increase potency. Mitochondrial drug localization is accomplished using (1) the mitochondrial membrane potential, (2) affinity of a carrier to mitochondria-specific components (e.g. lipids), (3) piggybacking on the cells own mitochondria trafficking systems, or (4) nanoparticle-based approaches. In this review, we briefly consider the mitochondrial delivery strategies and drug targets that illustrate the promise of these mitochondria-specific approaches in the design of TBI pharmacotherapy. This article is part of the Special Issue entitled "Novel Treatments for Traumatic Brain Injury".

The influence of immunological stressors on traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide, and typically involves a robust immune response. Although a great deal of preclinical research has been conducted to identify an effective treatment, all phase III clinical trials have been unsuccessful to date. These translational shortcomings are in part due to a failure to recognize and account for the heterogeneity of TBI, including how extracranial factors can influence the aftermath of TBI. For example, most preclinical studies have utilized isolated TBI models in young adult males, while clinical trials typically involve highly heterogeneous patient populations (e.g., different mechanisms of injury, a range of ages, presence of polytrauma or infection). This paper will review the current, albeit limited literature related to how TBI is affected by common concomitant immunological stressors. In particular, discussion will focus on whether extracranial trauma (i.e., polytrauma), infection, and age/immunosenescence can influence TBI pathophysiology, and thereby may result in a different brain injury than what would have occurred in an isolated TBI. It is concluded that these immunological stressors are all likely to be TBI modifiers that should be further studied and could impact translational treatment strategies.

Nosocomial bloodstream infections in neurosurgery: a 10-year analysis in a center with high antimicrobial drug-resistance prevalence

BACKGROUND

Data on nosocomial bloodstream infections (NBSI) in neurosurgery is limited. This study aimed to analyze the epidemiology, microbiology, outcome, and risk factors for death in neurosurgical patients with NBSI in a multidrug resistant setting.

METHODS

Neurosurgical patients with a confirmed NBSI within the period 2003-2012 were retrospectively analyzed. NBSI was diagnosed when a pathogen was isolated from a blood sample obtained after the first 48 h of hospitalization. Patients' demographic, clinical, and microbiological data were recorded and analyzed using univariate and multivariate analysis.

RESULTS

A total of 236 patients with NBSI were identified and 378 isolates were recovered from blood cultures. Incidence of NBSI was 4.3 infections/1000 bed-days. Gram-negative bacteria slightly predominated (54.5 %). The commonest bacteria were coagulase-negative staphylococci (CoNS, 26 %), Klebsiella pneumoniae (15.3 %), Pseudomonas aeruginosa (14.8 %), and Acinetobacter baumannii (13.2 %). Carbapenem resistance was found in 90 % of A. baumannii, in 66 % of P. aeruginosa, and in 22 % (2003-2007) to 77 % (2008-2012) of K. pneumoniae isolates (p < 0.05). Most CoNS and Staphylococcus aureus isolates (94 and 80 %, respectively) were methicillin-resistant. All Gram-negative isolates were sensitive to colistin and all Gram-positive isolates were sensitive to vancomycin and linezolid. Antimicrobial consumption decreased after 2007 (p < 0.05). Overall mortality was 50.4 %. In multivariate analysis, advanced age and stay in an Intermediate Care Unit (IMCU) were independent risk factors for in-hospital mortality (p < 0.05).

CONCLUSIONS

Overall, high incidence of NBSI and considerable resistance of Gram-positive and particularly Gram-negative bacteria were noted in neurosurgical patients. Mortality was high with advanced age and stay in IMCU being the most important death-related factors.

Traumatic Brain Injury and Peripheral Immune Suppression: Primer and Prospectus

Nosocomial infections are a common occurrence in patients following traumatic brain injury (TBI) and are associated with an increased risk of mortality, longer length of hospital stay, and poor neurological outcome. Systemic immune suppression arising as a direct result of injury to the central nervous system (CNS) is considered to be primarily responsible for this increased incidence of infection, a view strengthened by recent studies that have reported novel changes in the composition and function of the innate and adaptive arms of the immune system post-TBI. However, our knowledge of the mechanisms that underlie TBI-induced immune suppression is equivocal at best. Here, after summarizing our current understanding of the impact of TBI on peripheral immunity and discussing CNS-mediated regulation of immune function, we propose roles for a series of novel mechanisms in driving the immune suppression that is observed post-TBI. These mechanisms, which have never been considered before in the context of TBI-induced immune paresis, include the CNS-driven emergence into the circulation of myeloid-derived suppressor cells and suppressive neutrophil subsets, and the release from injured tissue of nuclear and mitochondria-derived damage associated molecular patterns. Moreover, in an effort to further our understanding of the mechanisms that underlie TBI-induced changes in immunity, we pose throughout the review a series of questions, which if answered would address a number of key issues, such as establishing whether manipulating peripheral immune function has potential as a future therapeutic strategy by which to treat and/or prevent infections in the hospitalized TBI patient.

Frequency and impact of intensive care unit complications on moderate-severe traumatic brain injury: early results of the Outcome Prognostication in Traumatic Brain Injury (OPTIMISM) Study

BACKGROUND

Known predictors of adverse outcomes in patients with moderate-severe TBI (msTBI) explain only a relatively small proportion of patient-related outcomes. The frequency and impact of intensive care unit complications (ICU-COMPL) on msTBI-associated outcomes are poorly understood.

METHODS

In 213 consecutive msTBI patients admitted to a Level I Trauma Center neuro trauma ICU, twenty-eight ICU-COMPL (21 medical and 7 neurological) were prospectively collected and adjudicated by group consensus, using pre-defined criteria. We determined frequencies, and explored associations of ICU-COMPL and hospital discharge outcomes using multivariable logistic regression.

RESULTS

The average age of the study sample was 53 years, and the median presenting Glasgow Coma Scale and Injury Severity Scores were 5 and 27, respectively. Hyperglycemia (79%), fever (62%), systemic inflammatory response syndrome (60%), and hypotension requiring vasopressors (42%) were the four most common medical ICU-COMPL. Herniation (39%), intracranial rebleed (39%), and brain edema requiring osmotherapy (37%) were the three most common neurological ICU-COMPL. After adjusting for admission variables, duration of ventilation, and ICU length-of-stay, patients with brain edema (OR 5.8; 95% CI 2, 16.7) had a significantly increased odds for dying during hospitalization whereas patients with hospital-acquired urinary tract infection (UTI) had a decreased odds (OR 0.05; 95% CI 0.005, 0.6). Sensitivity analysis revealed that UTI occurred later, suggesting a non-causal association with survival. Brain herniation (OR 15.7; 95% CI 2.6, 95.4) was associated with an unfavorable functional status (GOS 1-3).

CONCLUSION

ICU-COMPL are very common after msTBI, have a considerable impact on short-term outcomes, and should be considered in the prognostication of these high risk patients. Survival associations of time-dependent complications warrant cautious interpretation.

Procalcitonin as a marker of sepsis and outcome in patients with neurotrauma: an observation study

BACKGROUND

Procalcitonin (PCT) is a reliable biomarker of sepsis and infection. The level of PCT associated with sepsis and infection in patients with traumatic brain injury is currently unknown. The purpose of this study was to investigate the value of PCT and C-reactive protein (CRP) as diagnostic markers of sepsis and to evaluate the prognostic value of these markers related to the severity of injury, sepsis and mortality.

METHODS

105 adult patients with neurotrauma were enrolled in this study from June 2011 to February 2013. PCT and CRP were measured at admission and 2, 3, 5 and 7 days after admission. The sepsis criteria established by American College of Chest Physicians /Society of Critical Care Medicine Consensus Conference were used to identify patients. Injury Severity Score (ISS) and Glasgow Coma Score (GCS) were used to assess the severity of the injury. All these patients were monitored for 28 days.

RESULTS

At admission, the median level of PCT was consistent with the severity of brain injury as follows: mild 0.08 ng/ml (0.05 - 0.13), moderate 0.25 ng/ml (0.11 - 0.55) and severe 0.31 ng/ml (0.17 - 0.79), but the range of CRP levels varied greatly within the given severity of brain injury. Seventy-one (67.6%) patients developed sepsis. The initial levels of PCT at admission were statistically higher in patients with sepsis, compared with patients with systemic inflammatory response syndrome (SIRS), but there were no differences in the initial concentration of CRP between sepsis and SIRS. After adjusting for these parameters, multivariate logistic regression analysis revealed that PCT was an independent risk factor for septic complications (p < 0.05). The areas under the ROCs at admission for the prediction of mortality were 0.76 (p < 0.05) and 0.733 for PCT and CRP, respectively.

CONCLUSIONS

Increased levels of PCT during the course of the ICU stay could be an important indicator for the early diagnosis of sepsis after neurotrauma. In addition, high serum levels of PCT in patients with neurotrauma at admission indicate an increased risk of septic complications, and the daily measurement of PCT assists in guiding antibiotic therapy in neurotrauma patients.

The risk of acquiring bacterial meningitis following surgery in Denmark, 1996-2009: a nationwide retrospective cohort study with emphasis on ear, nose and throat (ENT) and neurosurgery

SUMMARY

This paper estimates the risk of bacterial meningitis following surgery between 1996 and 2009 in Denmark. We conducted two retrospective nationwide cohort studies; first by linking notified bacterial meningitis cases to the National Patient Registry to see how many had undergone a surgical procedure; second, we scrutinized notified bacterial meningitis cases to see if the clinician suspected a surgical procedure to be the aetiology. We found that ear, nose and throat surgery had an 11-fold, and neurosurgery a sevenfold, increased risk compared to the reference group in the first 10 days following surgery. Streptococcus pneumoniae was the pathogen most often involved. Operation procedures involving penetration of dura mater was associated with increased risk for post-operative bacterial meningitis. In absolute numbers we found few bacterial meningitis cases after surgery; however, patients undergoing certain surgical procedures are at-risk and should be considered when national vaccination guidelines are revised.

Descriptive characteristics and rehabilitation outcomes in active duty military personnel and veterans with disorders of consciousness with combat- and noncombat-related brain injury

OBJECTIVE

To report the injury and demographic characteristics, medical course, and rehabilitation outcome for a consecutive series of veterans and active duty military personnel with combat- and noncombat-related brain injury and disorder of consciousness (DOC) at the time of rehabilitation admission.

DESIGN

Retrospective study.

SETTING

Rehabilitation center.

PARTICIPANTS

From January 2004 to October 2009, persons (N=1654) were admitted to the Polytrauma Rehabilitation System of Care. This study focused on the N=122 persons admitted with a DOC. Participants with a DOC were primarily men (96%), on active duty (82%), ≥12 years of education, and a median age of 25. Brain injury etiologies included mixed blast trauma (24%), penetrating (8%), other trauma (56%), and nontrauma (13%). Median initial Glasgow Coma Scale score was 3, and rehabilitation admission Glasgow Coma Scale score was 8. Individuals were admitted for acute neurorehabilitation approximately 51 days postinjury with a median rehabilitation length of stay of 132 days.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Recovery of consciousness and the FIM instrument.

RESULTS

Most participants emerged to regain consciousness during neurorehabilitation (64%). Average gains ± SD on the FIM cognitive and motor subscales were 19 ± 25 and 7 ± 8, respectively. Common medical complications included spasticity (70%), dysautonomia (34%), seizure occurrence (30%), and intracranial infection (22%). Differential outcomes were observed across etiologies, particularly for those with blast-related brain injury etiology.

CONCLUSIONS

Despite complex comorbidities, optimistic outcomes were observed. Individuals with severe head injury because of blast-related etiologies have different outcomes and comorbidities observed. Health-services research with a focus on prevention of comorbidities is needed to inform optimal models of care, particularly for combat injured soldiers with blast-related injuries.

Molecular epidemiology and the clinical significance of Acinetobacter baumannii complex isolated from cerebrospinal fluid in neurosurgical intensive care unit patients

OBJECTIVE

This study was intended to investigate the clinical significance and molecular epidemiology of Acinetobacter baumannii complex (ABC) isolated from cerebrospinal fluid (CSF) in neurosurgical intensive care unit (NSICU) patients, particularly comparing isolates from healthcare workers' (HCW) hands.

METHODS

We retrospectively reviewed the medical records of 30 patients with CSF cultures positive for ABC seen at our NSICU from the date it first opened, January 2007, to September 2010. Pulsed-field gel electrophoresis (PFGE) typing was performed on 68 strains isolated from 32 patients' CSF and 36 HCWs' hands.

RESULTS

ABC isolates were considered to be clinically significant in 21 (70.0%) patients but insignificant in the other nine (30.0%) patients. The prolonged (>7 days) use of cephalosporins was more common in patients with clinically significant ABC isolates (p = 0.049). Multiple drug resistance (MDR) was observed in 12 (57.1%) clinically significant isolates. Empirical antimicrobial therapies were not appropriate for nine of these 21 patients (42.8%). Mortality was significantly higher in the clinically significant group than in the clinically insignificant group (18/21 vs. 3/9; p = 0.008). Fifty-three isolates (77.9%) were grouped into 15 clusters, three of which contained possibly related isolates from patients' CSF and staff members' hands.

CONCLUSIONS

The fact that ABC isolates grown from CSF cultures do not always exhibit infection and have high multiple antibiotic resistance, including to carbapenems, should be borne in mind when planning treatment for these patients. In addition, HCWs' hands may play a significant role in transmission to patients, and compliance with infection control procedures, especially hand washing, must be enhanced in order to avoid ABC infections.