Epidemiologic features, risk factors, and outcome of sepsis in stroke patients treated on a neurologic intensive care unit

Machine learning model to predict sepsis in ICU patients with intracerebral hemorrhage

Patients with intracerebral hemorrhage (ICH) are highly susceptible to sepsis. This study evaluates the efficacy of machine learning (ML) models in predicting sepsis risk in intensive care units (ICUs) patients with ICH. We conducted a retrospective analysis on ICH patients using the MIMIC-IV database, randomly dividing them into training and validation cohorts. We identified sepsis prognostic factors using Least Absolute Shrinkage and Selection Operator (LASSO) and backward stepwise logistic regression. Several machine learning algorithms were developed and assessed for predictive accuracy, with external validation performed using the eICU Collaborative Research Database (eICU-CRD). We analyzed 2,214 patients, including 1,550 in the training set, 664 in the validation set, and 513 for external validation using the eICU-CRD. The Random Forest (RF) model outperformed others, achieving Area Under the Curves (AUCs) of 0.912 in training, 0.832 in internal validation, and 0.798 in external validation. Neural Network and Logistic Regression models recorded training AUCs of 0.840 and 0.804, respectively. ML models, especially the RF model, effectively predict sepsis in ICU patients with ICH, enabling early identification and management of high-risk cases.

Identification and Validation of an Explainable Prediction Model of Sepsis in Patients With Intracerebral Hemorrhage: Multicenter Retrospective Study

BACKGROUND

Sepsis is a life-threatening condition frequently observed in patients with intracerebral hemorrhage (ICH) who are critically ill. Early and accurate identification and prediction of sepsis are crucial. Machine learning (ML)-based predictive models exhibit promising sepsis prediction capabilities in emergency settings. However, their application in predicting sepsis among patients with ICH is still limited.

OBJECTIVE

The aim of the study is to develop an ML-driven risk calculator for early prediction of sepsis in patients with ICH who are critically ill and to clarify feature importance and explain the model using the Shapley Additive Explanations method.

METHODS

Patients with ICH admitted to the intensive care unit (ICU) from the Medical Information Mart for Intensive Care IV database between 2008 and 2022 were divided into training and internal test sets. The external test was performed using the eICU Collaborative Research Database, which includes over 200,000 ICU admissions across the United States between 2014 and 2015. Sepsis following ICU admission was identified using Sepsis-3.0 through clinical diagnosis combining elevation of the Sequential Organ Failure Assessment by ≥2 points with suspected infection. The Boruta algorithm was used for feature selection, confirming 29 features. Nine ML algorithms were used to construct the prediction models. Predictive performance was compared using several evaluation metrics, including the area under the receiver operating characteristic curve (AUC). The Shapley Additive Explanations technique was used to interpret the final model, and a web-based risk calculator was constructed for clinical practice.

RESULTS

Overall, 2414 patients with ICH were enrolled from the Medical Information Mart for Intensive Care IV database, with 1689 and 725 patients assigned to the training and internal test sets, respectively. An external test set of 2806 patients with ICH from the eICU database was used. Among the 9 ML models tested, the categorical boosting (CatBoost) model demonstrated the best discriminative ability. After reducing features based on their importance, an explainable final CatBoost model was developed using 8 features. The final model accurately predicted sepsis in internal (AUC=0.812) and external (AUC=0.771) tests.

CONCLUSIONS

We constructed a web-based risk calculator with 8 features based on the CatBoost model to assist clinicians in identifying people at high risk for sepsis in patients with ICH who are critically ill.

Associations between sepsis occurrence, hemoglobin level and mortality in patients with non-trauma hemorrhagic brain injuries: trajectory-based analysis

BACKGROUND

The impact of concurrent sepsis on the prognosis in patients with non-traumatic hemorrhagic brain injury (HBI) remains unclear, and the appropriate hemoglobin (HGB) level in HBI patients with sepsis has not been investigated. This study aimed to investigate the impact of sepsis in HBI and the prognosis of patients with different HGB trajectories with/without sepsis.

METHODS

The association between sepsis and prognosis (including neurologic outcome and 28-day mortality) in patients with non-trauma HBI was investigated, and multivariate logistic model, propensity score matching (PSM), and inverse-probability-weighted regression adjustment (IPWRA) were used to reach a causal relationship. Group-based trajectory analysis was adopted to explore the associations between HGB trajectories and outcomes.

RESULTS

A total of 3,040 patients were included. Compared with the HBI-without-sepsis group, the HBI-with-sepsis group had higher 28-day mortality and worse neurological outcomes. After adjusting for confounders, the association between sepsis and mortality remains significant in multivariate logistic model (OR 2.31, 95%CI 1.77-3.01), PSM analysis (212/942 vs. 130/942, p < 0.001) and IPWRA model (ATE 0.073, 95%CI 0.04-0.09). Based on 72-h HGB data, four HGB-trajectories were identified. In HBI-without-sepsis cohort, OR for mortality decreased from HGB-traj2 (OR: 0.56, 95% CI 0.33-0.96) to HGB-traj4 (0.26, 95% CI 0.11-0.59), referred to HGB-traj1. But this decreasing trend became non-significant in HBI-with-sepsis cohort. Sensitivity analyses showed similar results.

CONCLUSION

In HBI, concurrent sepsis was associated with higher mortality rate. Furthermore, there was an inverse gradient relationship between HGB level and mortality in HBI patients without sepsis, while this association became non-significant in those with sepsis.

A Single-Center Retrospective Study of Bacterial Infections After Acute Ischemic Stroke: The Prevalence Before and During the COVID-19 Pandemic

Background and Objectives: The management of ischemic stroke involves care that is integrated and comprehensive, including the prevention of infection complications. This study aimed to investigate the prevalence and profile of bacterial infections after acute ischemic stroke both before and during the coronavirus disease 2019 (COVID-19) pandemic. Materials and Methods: A retrospective cross-sectional study examined the medical records of hospitalized acute ischemic stroke patients who had microbiological cultures taken at the National Brain Center Hospital Prof. Dr. dr. Mahar Mardjono, Jakarta, Indonesia, from 1 January 2018 to 31 December 2021. The percentage of positive bacterial growth in the microbiological cultures was used to determine the prevalence of bacterial infection after acute ischemic stroke. Results: A total of 519 patients met the study criteria, including 48 and 471 patients with infections before and during the COVID-19 pandemic. The prevalence of bacterial infection after acute ischemic stroke was 17.9%. There were significant differences in the prevalence of bacterial infection after acute ischemic stroke before and during the COVID-19 pandemic (87.5% vs. 10.8%). Staphylococcus sp. and Klebsiella sp. were the most frequently observed. The risk factors that influenced bacterial infection after acute ischemic stroke were intensive care stay (OR 0.22; 95%CI 0.13-0.39, p-value < 0.001), sepsis (OR 1.99; 95%CI 1.12-3.53, p-value = 0.019), COVID-19 infection (OR 4.81; 95%CI 2.64-8.76, p-value < 0.001), the use of steroids (OR 0.31; 95%CI 0.14-0.67, p-value = 0.003), and the use of TPN (OR 0.34; 95%CI 0.13-0.86, p-value = 0.022). Conclusions: Following the start of the COVID-19 pandemic, there was a decrease in the prevalence of bacterial infections after AIS. Patients with bacterial infections had different profiles before and during the COVID-19 pandemic.

Sepsis compromises post-ischemic stroke neurological recovery and is associated with sex differences

AIMS

Infection is a complication after stroke and outcomes vary by sex. Thus, we investigated if sepsis affects brain from ischemic stroke and sex involvement.

MAIN METHODS

Male and female Wistar rats, were submitted to middle cerebral artery occlusion (MCAO) and after 7 days sepsis to cecal ligation and perforation (CLP). Infarct size, neuroinflammation, oxidative stress, and mitochondrial activity were quantified 24 h after CLP in the prefrontal cortex and hippocampus. Survival and neurological score were assessed up to 15 days after MCAO or 8 days after CLP (starting at 2 h after MCAO) and memory at the end.

KEY FINDINGS

CLP decreased survival, increased neurological impairments in MCAO females. Early, in male sepsis following MCAO led to increased glial activation in the brain structures, and increased TNF-α and IL-1β in the hippocampus. All groups had higher IL-6 in both tissues, but the hippocampus had lower IL-10. CLP potentiated myeloperoxidase (MPO) in the prefrontal cortex of MCAO male and female. In MCAO+CLP, only male increased MPO and nitrite/nitrate in hippocampus. Males in all groups had protein oxidation in the prefrontal cortex, but only MCAO+CLP in the hippocampus. Catalase decreased in the prefrontal cortex and hippocampus of all males and females, and MCAO+CLP only increased this activity in males. Female MCAO+CLP had higher prefrontal cortex complex activity than males. In MCAO+CLP-induced long-term memory impairment only in females.

SIGNIFICANCE

The parameters evaluated for early sepsis after ischemic stroke show a worse outcome for males, while females are affected during long-term follow-up.

Association of Blood Pressure Variability With Death and Discharge Destination Among Critically Ill Patients With and Without Stroke

BACKGROUND AND OBJECTIVES

It is unclear whether blood pressure variability's (BPV) association with worse outcomes is unique to patients with stroke or a risk factor among all critically ill patients. We (1) determined whether BPV differed between patients with stroke and nonstroke patients, (2) examined BPV's associations with in-hospital death and favorable discharge destination in patients with stroke and nonstroke patients, and (3) assessed how minimum mean arterial pressure (MAP)-a correlate of illness severity and cerebral perfusion-affects these associations.

METHODS

This is a retrospective analysis of adult intensive care unit patients hospitalized between 2001 and 2012 from the Medical Information Mart for Intensive Care III database. Confounder-adjusted logistic regressions determined associations between BPV, measured as SD and average real variability (ARV), and (1) in-hospital death and (2) favorable discharge, with testing of minimum MAP for effect modification.

RESULTS

BPV was higher in patients with stroke (N = 2,248) compared with nonstroke patients (N = 9,085) (SD mean difference 2.3, 95% CI 2.1-2.6, p < 0.01). After adjusting for minimum tertile of MAP and other confounders, higher SD remained significantly associated (p < 0.05) with higher odds of in-hospital death for patients with acute ischemic strokes (AISs, odds ratio [OR] 2.7, 95% CI 1.5-4.8), intracerebral hemorrhage (ICH, OR 2.6, 95% CI 1.6-4.3), subarachnoid hemorrhage (SAH, OR 3.4, 95% CI 1.2-9.3), and pneumonia (OR 1.9, 95% CI 1.1-3.3) and lower odds of favorable discharge destination in patients with ischemic stroke (OR 0.3, 95% CI 0.2-0.6) and ICH (OR 0.4, 95% CI 0.3-0.6). No interaction was found between minimum MAP tertile with SD (p > 0.05). Higher ARV was not significantly associated with increased risk of death in any condition when adjusting for illness severity but portended worse discharge destination in those with AIS (OR favorable discharge 0.4, 95% CI 0.3-0.7), ICH (OR favorable discharge 0.5, 95% CI 0.3-0.7), sepsis (OR favorable discharge 0.8, 95% CI 0.6-1.0), and pneumonia (OR favorable discharge 0.5, 95% CI 0.4-0.8).

DISCUSSION

BPV is higher and generally associated with worse outcomes among patients with stroke compared with nonstroke patients. BPV in patients with AIS and patients with ICH may be a marker of central autonomic network injury, although clinician-driven blood pressure goals likely contribute to the association between BPV and outcomes.

Derivation and validation of a screening tool for stroke-associated sepsis

BACKGROUND

Post-stroke infections may cause sepsis, which is associated with poor clinical outcome. Sepsis is defined by life-threatening organ dysfunction that can be identified using the Sequential Organ Failure Assessment (SOFA) score. The applicability of the SOFA score for patients not treated on an intensive care unit (ICU) is limited. The aim of this study was to develop and validate an easier-to-use modification of the SOFA score for stroke patients.

METHODS

Using a registry-based cohort of 212 patients with large vessel occlusion stroke and infection, potential predictors of a poor outcome indicating sepsis were assessed by logistic regression. The derived score was validated on a separate cohort of 391 patients with ischemic stroke and infection admitted to our hospital over a period of 1.5 years.

RESULTS

The derived Stroke-SOFA (S-SOFA) score included the following predictors: National Institutes of Health stroke scale ≥ 14, peripheral oxygen saturation < 90%, mean arterial pressure < 70 mmHg, thrombocyte count < 150 10⁹/l and creatinine ≥ 1.2 mg/dl. The area under the receiver operating curve for the prediction of a poor outcome indicating sepsis was 0.713 [95% confidence interval: 0.665-0.762] for the S-SOFA score, which was comparable to the standard SOFA score (0.750 [0.703-0.798]), but the prespecified criteria for non-inferiority were not met (p = 0.115). However, the S-SOFA score was non-inferior compared to the SOFA score in non-ICU patients (p = 0.013).

CONCLUSIONS

The derived S-SOFA score may be useful to identify non-ICU patients with stroke-associated sepsis who have a high risk of a poor outcome.

Predictive value of risk factors for prognosis of patients with sepsis in intensive care unit

Sepsis has emerged as a major global public health concern due to its elevated mortality and high cost of care. This study aimed to evaluate the risk factors associated with the mortality of sepsis patients in the Intensive Care Unit (ICU), and to intervene in the early stages of sepsis in order to improve patient outcomes and reduce mortality. From January 1st, 2021 to December 31st, 2021, Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Huashan Hospital Affiliated to Fudan University, and The Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese Medicine were designated as sentinel hospitals, and sepsis patients in their respective ICU and Emergency ICU were selected as research subjects, and divided into survivors and non-survivors according to their discharge outcomes. The mortality risk of sepsis patients was subsequently analyzed by logistic regression. A total of 176 patients with sepsis were included, of which 130 (73.9%) were survivors and 46 (26.1%) were non-survivors. Factors identified as having an impact on death among sepsis patients included female [Odds Ratio (OR) = 5.135, 95% confidence interval (CI): 1.709, 15.427, P = .004)], cardiovascular disease (OR = 6.272, 95% CI: 1.828, 21.518, P = .004), cerebrovascular disease (OR = 3.133, 95% CI: 1.093, 8.981, P = .034), pulmonary infections (OR = 6.700, 95% CI: 1.744, 25.748, P = .006), use of vasopressors (OR = 34.085, 95% CI: 10.452, 111.155, P < .001), WBC < 3.5 × 109/L (OR = 9.752, 95% CI: 1.386, 68.620, P = .022), ALT < 7 U/L (OR = 7.672, 95% CI: 1.263, 46.594, P = .027), ALT > 40 U/L (OR = 3.343, 95% CI: 1.097, 10.185, P = .034). Gender, cardiovascular disease, cerebrovascular disease, pulmonary infections, the use of vasopressors, WBC, and ALT are important factors in evaluating the prognostic outcome of sepsis patients in the ICU. This suggests that medical professionals should recognize them expeditiously and implement aggressive treatment tactics to diminish the mortality rate and improve outcomes.

CCL5/CCR5-mediated peripheral inflammation exacerbates blood‒brain barrier disruption after intracerebral hemorrhage in mice

BACKGROUND

Owing to metabolic disequilibrium and immune suppression, intracerebral hemorrhage (ICH) patients are prone to infections; according to a recent global analysis of stroke cases, approximately 10 million new-onset ICH patients had experienced concurrent infection. However, the intrinsic mechanisms underlying the effects of infection related peripheral inflammation after ICH remain unclear.

METHODS

Lipopolysaccharide (LPS) was intraperitoneally injected into ICH model mice to induce peripheral inflammation. Neurobehavioral deficits, blood‒brain barrier (BBB) disruption, and the expression of CCR5, JAK2, STAT3, and MMP9 were evaluated after treatment with recombinant CCL5 (rCCL5) (a CCR5 ligand), maraviroc (MVC) (an FDA-approved selective CCR5 antagonist), or JAK2 CRISPR plasmids.

RESULTS

Our study revealed that severe peripheral inflammation increased CCL5/CCR5 axis activation in multiple inflammatory cell types, including microglia, astrocytes, and monocytes, and aggravated BBB disruption and neurobehavioral dysfunction after ICH, possibly in part through the JAK2/STAT3 signaling pathway.

CONCLUSIONS

CCR5 might be a potential target for the clinical treatment of infection-induced exacerbation of BBB disruption following ICH.

One-Year Outcome Trajectories and Factors Associated with Functional Recovery Among Survivors of Intracerebral and Intraventricular Hemorrhage With Initial Severe Disability

Importance

Patients who survive severe intracerebral hemorrhage (ICH) and intraventricular hemorrhage (IVH) typically have poor functional outcome in the short term and understanding of future recovery is limited.

Objective

To describe 1-year recovery trajectories among ICH and IVH survivors with initial severe disability and assess the association of hospital events with long-term recovery.

Design, Setting, and Participants

This post hoc analysis pooled all individual patient data from the Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage phase 3 trial (CLEAR-III) and the Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation (MISTIE-III) phase 3 trial in multiple centers across the US, Canada, Europe, and Asia. Patients were enrolled from August 1, 2010, to September 30, 2018, with a follow-up duration of 1 year. Of 999 enrolled patients, 724 survived with a day 30 modified Rankin Scale score (mRS) of 4 to 5 after excluding 13 participants with missing day 30 mRS. An additional 9 patients were excluded because of missing 1-year mRS. The final pooled cohort included 715 patients (71.6%) with day 30 mRS 4 to 5. Data were analyzed from July 2019 to January 2022.

Exposures

CLEAR-III participants randomized to intraventricular alteplase vs placebo. MISTIE-III participants randomized to stereotactic thrombolysis of hematoma vs standard medical care.

Main Outcomes and Measures

Primary outcome was 1-year mRS. Patients were dichotomized into good outcome at 1 year (mRS 0 to 3) vs poor outcome at 1 year (mRS 4 to 6). Multivariable logistic regression models assessed associations between prospectively adjudicated hospital events and 1-year good outcome after adjusting for demographic characteristics, ICH and IVH severity, and trial cohort.

Results

Of 715 survivors, 417 (58%) were male, and the overall mean (SD) age was 60.3 (11.7) years. Overall, 174 participants (24.3%) were Black, 491 (68.6%) were White, and 49 (6.9%) were of other races (including Asian, Native American, and Pacific Islander, consolidated owing to small numbers); 98 (13.7%) were of Hispanic ethnicity. By 1 year, 129 participants (18%) had died and 308 (43%) had achieved mRS 0 to 3. In adjusted models for the combined cohort, diabetes (adjusted odds ratio [aOR], 0.50; 95% CI, 0.26-0.96), National Institutes of Health Stroke Scale (aOR, 0.93; 95% CI, 0.90-0.96), severe leukoaraiosis (aOR, 0.30; 95% CI, 0.16-0.54), pineal gland shift (aOR, 0.87; 95% CI, 0.76-0.99]), acute ischemic stroke (aOR, 0.44; 95% CI, 0.21-0.94), gastrostomy (aOR, 0.30; 95% CI, 0.17-0.50), and persistent hydrocephalus by day 30 (aOR, 0.37; 95% CI, 0.14-0.98) were associated with lack of recovery. Resolution of ICH (aOR, 1.82; 95% CI, 1.08-3.04) and IVH (aOR, 2.19; 95% CI, 1.02-4.68) by day 30 were associated with recovery to good outcome. In the CLEAR-III model, cerebral perfusion pressure less than 60 mm Hg (aOR, 0.30; 95% CI, 0.13-0.71), sepsis (aOR, 0.05; 95% CI, 0.00-0.80), and prolonged mechanical ventilation (aOR, 0.96; 95% CI, 0.92-1.00 per day), and in MISTIE-III, need for intracranial pressure monitoring (aOR, 0.35; 95% CI, 0.12-0.98), were additional factors associated with poor outcome. Thirty-day event-based models strongly predicted 1-year outcome (area under the receiver operating characteristic curve [AUC], 0.87; 95% CI, 0.83-0.90), with significantly improved discrimination over models using baseline severity factors alone (AUC, 0.76; 95% CI, 0.71-0.80; P < .001).

Conclusions and Relevance

Among survivors of severe ICH and IVH with initial poor functional outcome, more than 40% recovered to good outcome by 1 year. Hospital events were strongly associated with long-term functional recovery and may be potential targets for intervention. Avoiding early pessimistic prognostication and delaying prognostication until after treatment may improve ability to predict future recovery.

Sepsis in Patients With Large Vessel Occlusion Stroke–Clinical Characteristics and Outcome

Background

Infections are an important complication after stroke and negatively affect clinical outcome. While pneumonia and urinary tract infections are well recognized after stroke, the incidence and consequences of sepsis remain unclear. The aim of this study was to evaluate the frequency and characteristics of sepsis in patients undergoing endovascular therapy for large vessel occlusion stroke, and its association with clinical outcome.

Methods

We analyzed a cohort of patients who underwent endovascular therapy at a single center between 2016 and 2020. The diagnosis and timing of infections and Sequential Organ Failure Assessment scores were evaluated retrospectively to identify patients with sepsis. Patients with sepsis were compared to controls regarding clinical characteristics and outcome.

Results

Fifty-four of 406 patients (13.3%) were found to have sepsis. The median onset of sepsis was 2 days after admission. The majority of cases (85.2%) was caused by pneumonia. At 3 months, 72.5% of patients with sepsis were bedridden or dead compared to 25.7 and 42.7% of controls and patients with an infection without sepsis, respectively. The adjusted odds ratio (95% confidence interval) for a poor outcome was 5.4 (1.6–17.6) for patients with sepsis vs. controls, and 2.0 (0.8–5.2) for patients with sepsis vs. patients with an infection without sepsis.

Conclusions

Sepsis is a frequent complication after large vessel occlusion stroke, and may be associated with a poor clinical outcome. More studies are needed to determine specific risk factors and measures to early recognize and reduce the possibly negative impact of sepsis on outcome after stroke.

Gut microbiome and neurocritically ill patients

Since the times of Rokitansky and Cushing, we have been fascinated by the connections between the gut and the brain. Recent advances in next-generation sequencing techniques have shown that this relationship is even more complex and integral to our sense of self than previously imagined. As these techniques refine our understanding of the abundance and diversity of the gut bacterial microbiome, the relationship between the gut and the brain has been redefined. Now, this is understood as a complex symbiotic network with bidirectional communication, the gut-brain axis. The implication of this communication involves an intense focus of research on a variety of chronic psychiatric, neurological, neurodegenerative, and neuro-oncological diseases. Recently, the gut-brain axis has been studied in neurologically ill patients requiring intensive care. Preliminary studies have shown that acute brain injury changes the bacterial phenotype from one that is symbiotic with the host human to one that is pathologic, termed the “pathobiome.” This can contribute to nosocomial pneumonia and sepsis. The first studies in neurologically ill patients in the neurointensive care unit (NeuroICU) demonstrated changes in the gut microbiome between neuroICU patients and healthy matched subjects. Specifically, a decrease in short-chain fatty acid-producing bacteria and increase in harmful gut microbes have been associated with mortality and decreased function at discharge. Although these preliminary findings are exciting and have opened a new field of research in the complex NeuroICU population, there are several limitations and challenges. Further investigation is needed to confirm these correlations and understand their implications on patients in a complex intensive care environment.

Fasting blood glucose-to-glycated hemoglobin ratio and all-cause mortality among Chinese in-hospital patients with acute stroke: a 12-month follow-up study

BACKGROUND

Stroke is a leading cause of death and functional impairment in older people. To assess the prospective association between fasting blood glucose-to-glycated hemoglobin ratio and all-cause mortality and poor prognosis in stroke patients.

METHODS

A total of 971 Chinese inpatients with acute stroke (mean age of 65.7) were consecutively enrolled in the prospective clinical study and followed up for 12 months after discharge. Stress hyperglycemia was measured using the ratio of fasting blood glucose (FBG, mmol/L)/glycated hemoglobin (HbA1c, %). The primary outcome was all-cause mortality, and secondary outcomes were poor prognosis defined as infectious complications, a National Institutes of Health Stroke Scale (NIHSS) score ≥ 6, a Barthel Index score ≤ 60, or a modified Rankin Scale (mRS) score of 3-6, presented as multivariate-adjusted odds ratios (ORs) with 95% confidence intervals (CIs) across the quartiles of the FBG/HbA1c ratio.

RESULTS

There were 35 (4.1%) all-cause deaths at 3 months and 85 (11.4%) at 12 months. The inpatients with the highest quartile of the FBG/HbA1c ratio had a higher risk of all-cause death at 3 months (adjusted OR: 5.16, 95% CI: 1.03-25.74) and at 12 months (adjusted OR: 2.59, 95% CI: 1.14-5.89)) and a higher risk of infectious complications (adjusted OR 2.37, 95% CI 1.27-4.43) and dysfunction (adjusted OR 1.79, 95% CI 1.06-3.01) during hospitalization than inpatients with the lowest quartile.

CONCLUSIONS

Stress hyperglycemia, measured by the FBG/HbA1c ratio, was associated with an increased risk of adverse outcomes, including all-cause death, infectious complications, and dysfunction after stroke.

Incidence, Risk Factors and Outcomes of Sepsis in Critically Ill Post-craniotomy Patients: A Single-Center Prospective Cohort Study

Background

Data concerning the epidemiology of sepsis in critically ill post-craniotomy patients are scarce. This study aimed to assess the incidence, risk factors, and outcomes of sepsis in this population.

Methods

This was a single-center prospective cohort study. Post-craniotomy patients admitted to the intensive care unit (ICU) were screened daily for the presence of infection and sepsis.

Results

Of the 900 included patients, 300 developed sepsis. The cumulative incidence of sepsis was 33.3% [95% confidence interval (CI), 30.2–36.4%]. Advanced age, male, hypertension, trauma, postoperative intracranial complications, and lower Glasgow Coma Scale (GCS) on the first postoperative day were independent risk factors of sepsis. Septic patients had higher hospital mortality (13.7 vs. 8.3%, P = 0.012), longer ICU length of stay (LOS) (14 vs. 4 days, P < 0.001), longer hospital LOS (31 vs. 19 days, P < 0.001), and higher total medical cost (CNY 138,394 vs. 75,918, P < 0.001) than patients without sepsis.

Conclusion

Sepsis is a frequent complication in critically ill post-craniotomy patients. Advanced age, male, hypertension, trauma, postoperative intracranial complications, and lower GCS on the first postoperative day were independent risk factors of sepsis.

Sepsis-Exacerbated Brain Dysfunction After Intracerebral Hemorrhage

Sepsis susceptibility is significantly increased in patients with intracerebral hemorrhage (ICH), owing to immunosuppression and intestinal microbiota dysbiosis. To date, ICH with sepsis occurrence is still difficult for clinicians to deal with, and the mortality, as well as long-term cognitive disability, is still increasing. Actually, intracerebral hemorrhage and sepsis are mutually exacerbated via similar pathophysiological mechanisms, mainly consisting of systemic inflammation and circulatory dysfunction. The main consequence of these two processes is neural dysfunction and multiple organ damages, notably, via oxidative stress and neurotoxic mediation under the mediation of central nervous system activation and blood-brain barrier disruption. Besides, the comorbidity-induced multiple organ damages will produce numerous damage-associated molecular patterns and consequently exacerbate the severity of the disease. At present, the prospective views are about operating artificial restriction for the peripheral immune system and achieving cross-tolerance among organs via altering immune cell composition to reduce inflammatory damage.

Readmission Rates in Stroke Patients with and without Infections: Incidence and Risk Factors

BACKGROUND

Stroke patients are at increased risk for acquiring infections in the hospital and risk of readmission. We aimed to examine whether an infection acquired during the initial stroke admission contributes to increased risk of readmission and infection during readmission.

METHODS

We performed a retrospective cohort study incorporating all adult ischemic stroke patients from three New York City hospitals from 2006 to 2016. A validated computer algorithm defined infections based on electronically-available laboratory culture data. Multivariable logistic regression was used to evaluate the crude and adjusted association of infections present on admission (IPOA) and healthcare-associated infections (HAI) with 60-day readmissions, and infection during readmission.

RESULTS

Among the 10,436 stroke patients, 17% had infections during initial admission of which 52% were IPOA and 48% were HAI. The risk of readmission was significantly higher for those with HAIs (OR = 1.40; 95% CI: 1.20-1.64) and IPOA (OR = 1.26; 95% CI: 1.09-1.47). The presence of infection during the 60-day readmission was also independently predicted by HAI (OR = 3.27; 95% CI: 2.60-4.12) and IPOA (OR = 2.54; 95% CI: 2.01-3.22). Patients with a Gram-negative infection were not at higher odds for readmission compared to patients with a Gram-positive infection (OR 1.07, 95%CI 0.81-1.42).

CONCLUSION

Among stroke patients, HAI and IPOA were predictors of readmission within 60 days and infection during readmission.

Lipopolysaccharide-induced sepsis-like state compromises post-ischemic neurological recovery, brain tissue survival and remodeling via mechanisms involving microvascular thrombosis and brain T cell infiltration

Sepsis predisposes for poor stroke outcome. This association suggests that sepsis disturbs post-ischemic tissue survival and brain remodeling. To elucidate this link, we herein exposed mice to 30 min intraluminal middle cerebral artery occlusion (MCAO) and induced a sepsis-like state at 72 h post-ischemia by intraperitoneal delivery of Escherichia coli lipopolysaccharide (LPS; three doses of 0.1 or 1 mg/kg, separated by 6 h), a major component of the bacterium's outer membrane. Neurological recovery, ischemic injury, brain remodeling and immune responses were evaluated over up to 56 days post-sepsis (dps) by behavioral tests, immunohistochemistry and flow cytometry. Delivery of 1 mg/kg but not 0.1 mg/kg LPS reduced rectal temperature over 48 h by up to 3.4 ± 3.1 °C, increased general and focal neurological deficits in the Clark score over 72 h and increased motor-coordination deficits in the tight rope test over up to 21 days. Notably, 1 mg/kg, but not 0.1 mg/kg LPS increased intercellular adhesion molecule-1 abundance on ischemic microvessels, increased microvascular thrombosis and increased patrolling monocyte and T cell infiltrates in ischemic brain tissue at 3 dps. Infarct volume was increased by 1 mg/kg, but not 0.1 mg/kg LPS at 3 dps (that is, 6 days post-MCAO), as was brain atrophy at 28 and 56 dps. Microglial activation in ischemic brain tissue, evaluated by morphology analysis of Iba-1 immunostainings, was transiently increased by 0.1 and 1 mg/kg LPS at 3 dps. Our data provide evidence that neurological recovery and brain remodeling are profoundly compromised in the ischemic brain post-sepsis as a consequence of cerebral thromboinflammation.

Focal brain ischemia in mice does not cause electrophysiological signs of critical illness neuropathy

OBJECTIVE

Critical illness polyneuropathy (CIP) is a common complication of severe systemic illness treated in intensive care medicine. Ischemic stroke leads to an acute critical injury of the brain with hemiparesis, immunosuppression and subsequent infections, all of which require extended medical treatment. Stroke-induced sarcopenia further contributes to poor rehabilitation and is characterized by muscle wasting and denervation in the paralytic, but also the unaffected limbs. Therefore, we asked whether stroke leads to an additional CIP-like neurodegeneration.

RESULTS

Focal brain ischemia was induced in adult mice by 60-min middle cerebral artery occlusion (MCAo) following reperfusion and led to functional deficits and marked hemispheric brain atrophy. Nerve conduction function and muscle potentials were measured in the ipsilateral sciatic nerve and gastrocnemius and quadriceps muscle with electroneurography/-myography on days 10, 22, 44 after stroke. An additional crush-injury to the sciatic nerve was included in two sham mice as positive control (sham +). We found no differences in nerve conduction function nor spontaneous electromyographic activity between MCAo and sham animals. Sham + mice developed marked reduction of the motor action potential amplitudes and conduction velocities with pathologic spontaneous activity. In conclusion, we found no peripheral nerve dysfunction/degeneration as signs of a CIP-like phenotype after MCAo.

Prediction of mortality after evacuation of supratentorial intracerebral hemorrhage using NSQIP data

Spontaneous intracerebral hemorrhage (sICH) is associated with high rates of morbidity and mortality. Neurosurgical clot evacuation is controversial but often a life saving maneuver in the setting of severe mass effect and cerebral herniation. Outcomes from large multicenter databases are sparsely reported. Patients who underwent craniotomy for evacuation of a supratentorial sICH between 2006 and 2017 were systematically extracted from the American College of Surgeons National Surgical Quality Improvement Program Participant Use Files. Our primary outcomes of interest were 30-day mortality, non-routine discharge disposition, and extended length of stay ([eLOS], defined as the top quartile for the cohort). Individual binary logistic regression models were constructed to query the associations between pre- and perioperative variables and each outcome. A total of 751 patients met the inclusion criteria. The 30-day mortality rate was 23.3% and increased from 2011 to 2017 (pooled OR 2.060 [95% CI 1.437 - 2.953]). Older age, morbid obesity, preoperative mechanical ventilation, preoperative systemic inflammatory response syndrome (SIRS) or septic shock, and thrombocytopenia were associated with mortality. Older age, race, and preoperative mechanical ventilation were associated with non-routine discharge. Patients who were mechanically ventilated or were insulin-dependent diabetics had greater odds of experiencing eLOS. A formula for estimating 30-day mortality was developed and found to have a strong linear association with actual mortality rates (R² = 0.777, p = 0.002). Preoperative mechanical ventilation is a consistent predictor of poor outcomes following surgery for supratentorial sICH. Mortality is also influenced by older age, body habitus, SIRS, septic shock, and thrombocytopenia.

Epidemiologic features and risk factors of sepsis in ischemic stroke patients admitted to intensive care: A prospective cohort study

BACKGROUND/OBJECTIVE

Stroke is the second leading cause of death globally that predisposed to sepsis. Therefore, this study was aimed to assess the risk factors and epidemiologic features of sepsis in ischemic stroke patients admitted to ICUs.

METHODS

Throughout this prospective study, we investigated all severe ischemic stroke patients admitted to ICUs of Namazi and Ali-Ashghar Hospitals in Shiraz. After ICU admission and diagnosing stroke by a neurologist according to NIHSS (National Institute of Health Stroke Scale) criteria, sepsis work-up was performed in all patients suspected to have sepsis. Then the incidence of sepsis and its risk factors in ICU admitted stroke patients were determined.

RESULTS

A total of 149 patients were screened in this study. The mean age of the participants was 65.37 ± 15.40 years old and 57.4% of them were male. Hypertension was the most common coexistent disease (74.6%) in stroke patients. Seventy-six patients (62.3%) were diagnosed with sepsis and pneumonia was the most common infection leading to sepsis in stroke patients. Our data showed significant differences between two groups in terms of APACHE-IV score (P < 0.001), NIHSS and APS (P < 0.001) before ICU admission (P < 0.001) and NIHSS at admission (P < 0.001); however, age (P = 0.07) and sex (P = 0.17) were not significantly different between the groups. Logistic regression analysis displayed that severe stroke (NIHSS = 21-42, OR = 49.09) and severe loss of consciousness (GCS < 8, OR = 27.95) at admission were the most essential predictive factors for sepsis after ischemic stroke.

CONCLUSIONS

This study showed that ICU patients with severe ischemic stroke were more susceptible to sepsis during the hospital course.

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.

Admission characteristics predictive of in-hospital death from hospital-acquired sepsis: A comparison to community-acquired sepsis

PURPOSE

Healthcare associated (HA) sepsis is associated with increased resource utilization and mortality compared with community acquired (CA) sepsis. The purpose of this study was to identify independent predictors of in-hospital mortality from HA-sepsis.

MATERIALS AND METHODS

Retrospective study of adult patients admitted with HA or CA-sepsis. Predictors were identified using logistic regression.

RESULTS

There were 3917 sepsis encounters, of which 3186 were CA and 731 were HA. History of stroke (83/731, 11%) and myocardial infarction (70/731, 10%) were higher in HA than CA-sepsis (stroke: 258/3186, 8%, p = .005; myocardial infarction: 213/3186, 7%, p = .007). HA-sepsis patients required more mechanical ventilation (153/731, 21%) than CA-patients (218/3186, 7%, p < .001) and had a higher rate of vasopressor use (334/731, 46%) than CA patients (832/3186, 26%, p < .001). The HA group had longer ICU lengths of stay (LOS) than CA patients did at 9 days and 2.8 days, respectively (p < .0001). Moderate to severe liver disease (OR = 27, 95%CI 1.4, 513, p = .031) and congestive heart failure (CHF, 5.81, 95% CI 1.3, 26, p = .025) were predictive of in-hospital mortality from HA-sepsis.

CONCLUSIONS

Liver disease and CHF were independent predictors of in-hospital mortality in HA-sepsis. HA-sepsis patients had increased prevalence of previous stroke, myocardial infarction, and liver disease.

Prevalence, Underlying Causes, and Preventability of Sepsis-Associated Mortality in US Acute Care Hospitals

IMPORTANCE

Sepsis is present in many hospitalizations that culminate in death. The contribution of sepsis to these deaths, and the extent to which they are preventable, is unknown.

OBJECTIVE

To estimate the prevalence, underlying causes, and preventability of sepsis-associated mortality in acute care hospitals.

DESIGN, SETTING, AND PARTICIPANTS

Cohort study in which a retrospective medical record review was conducted of 568 randomly selected adults admitted to 6 US academic and community hospitals from January 1, 2014, to December 31, 2015, who died in the hospital or were discharged to hospice and not readmitted. Medical records were reviewed from January 1, 2017, to March 31, 2018.

MAIN OUTCOMES AND MEASURES

Clinicians reviewed cases for sepsis during hospitalization using Sepsis-3 criteria, hospice-qualifying criteria on admission, immediate and underlying causes of death, and suboptimal sepsis-related care such as inappropriate or delayed antibiotics, inadequate source control, or other medical errors. The preventability of each sepsis-associated death was rated on a 6-point Likert scale.

RESULTS

The study cohort included 568 patients (289 [50.9%] men; mean [SD] age, 70.5 [16.1] years) who died in the hospital or were discharged to hospice. Sepsis was present in 300 hospitalizations (52.8%; 95% CI, 48.6%-57.0%) and was the immediate cause of death in 198 cases (34.9%; 95% CI, 30.9%-38.9%). The next most common immediate causes of death were progressive cancer (92 [16.2%]) and heart failure (39 [6.9%]). The most common underlying causes of death in patients with sepsis were solid cancer (63 of 300 [21.0%]), chronic heart disease (46 of 300 [15.3%]), hematologic cancer (31 of 300 [10.3%]), dementia (29 of 300 [9.7%]), and chronic lung disease (27 of 300 [9.0%]). Hospice-qualifying conditions were present on admission in 121 of 300 sepsis-associated deaths (40.3%; 95% CI 34.7%-46.1%), most commonly end-stage cancer. Suboptimal care, most commonly delays in antibiotics, was identified in 68 of 300 sepsis-associated deaths (22.7%). However, only 11 sepsis-associated deaths (3.7%) were judged definitely or moderately likely preventable; another 25 sepsis-associated deaths (8.3%) were considered possibly preventable.

CONCLUSIONS AND RELEVANCE

In this cohort from 6 US hospitals, sepsis was the most common immediate cause of death. However, most underlying causes of death were related to severe chronic comorbidities and most sepsis-associated deaths were unlikely to be preventable through better hospital-based care. Further innovations in the prevention and care of underlying conditions may be necessary before a major reduction in sepsis-associated deaths can be achieved.

Two-way Interaction Effects of Perioperative Complications on 30-Day Mortality in General Surgery

BACKGROUND

Multiple perioperative complications increase mortality risk, and certain complications synergistically increase this risk to a greater degree than might be expected if the complications were independent, but these effects are not well established.

METHODS

This is a retrospective cohort study of 422,827 intraabdominal general surgery patients (American College of Surgeons National Surgical Quality Improvement Program 2005-2011). Eight complications were evaluated: acute respiratory failure (ARF), acute kidney injury (AKI), sepsis/septic shock, stroke, cardiac arrest (CA), myocardial infarction (MI), deep vein thrombosis/pulmonary embolus, and transfusion. Each combination of two complications (28 total) was modeled using a Cox model for 30-day mortality, with adjustment for preoperative comorbidities and risk factors. Additive interaction was determined with the relative excess risk due to interaction (RERI). A positive RERI indicates that the mortality risk with both complications is greater than the sum of the individual mortality risks. Bonferroni correction was applied (α = 0.05/28 = 0.0018).

RESULTS

Seven combinations demonstrated positive interaction: sepsis-CA (RERI 88.1; p < 0.0001), ARF-AKI (RERI 50.5; p < 0.0001), AKI-sepsis (RERI 33.9; p < 0.0001), sepsis-stroke (RERI 33.9; p < 0.0001), ARF-stroke (RERI 32.3; p < 0.0001), AKI-MI (RERI 24.5; p = 0.0013), and ARF-sepsis (RERI 19.2; p < 0.0001). Two combinations demonstrated negative interaction: ARF-CA (RERI -65.1; p = 0.0017) and CA-transfusion (RERI -52.0, p < 0.0001).

CONCLUSIONS

Interaction effects exist between certain complications to increase the risk of short-term mortality. ARF, AKI, sepsis, and stroke were most likely to be involved in positive interactions. Further research into the mechanisms for these effects will be necessary to develop strategies to minimize the compounding effects of multiple complications in the perioperative period.

A systematic review on risk factors associated with sepsis in patients admitted to intensive care units

OBJECTIVE

We sought to systematically review data on the risk factors influencing the incidence of sepsis in patients admitted to intensive care units (ICUs).

REVIEW METHODS

An electronic search was undertaken in PubMed, MEDLINE, Scopus, and the Cochrane Library for studies reporting the risk factors of sepsis from the earliest available date up to December 30, 2016.

RESULTS

Among the 2978 articles, 14 studies met the inclusion criteria with a total of 56 164 participants from nine countries. The extracted risk factors were from the following categories: demographic, critical care interventions, surgery-related factors, pre-existing comorbidities, severity of organ injury, and biomarkers and biochemical and molecular indicators. From demographic factors, older age and male gender were associated with an increased risk of sepsis among ICU-admitted patients.

CONCLUSION

Our analysis comprehensively summarised the risk factors of sepsis in patients admitted to medical, surgical, neurologic, trauma, and general ICUs. Age, sex, and comorbidities were non-modifiable risk factors; however, critical care interventions and surgery-related factors were modifiable factors and suggest that improving the care of surgical patients and effective management of critical care interventions may play a key role in decreasing the development of sepsis in patients admitted to the ICUs.

No Awakening in Supratentorial Intracerebral Hemorrhage Is Potentially Caused by Sepsis-Associated Encephalopathy

BACKGROUND Acute supratentorial intracerebral hemorrhage (sICH) with secondary sepsis is increasing in frequency. We investigated whether no awakening (NA) after sICH with coma is potentially caused by sepsis-associated encephalopathy (SAE). MATERIAL AND METHODS A case-control study of 147 recruited sICH cases with NA and 198 sICH controls with subsequent awakening (SA) was performed at 2 centers in China. All patients underwent brain computed tomography (CT) scans on admission. The odds ratio (OR) of NA was calculated using logistic regression. RESULTS During the study period, 56.5% (83/147) of the patients with sICH with coma and NA had SAE, and 10% (20/198) with sICH with coma and SA had SAE; this difference between the 2 groups was significant (p<0.000). The sICH patients with coma and NA exhibited a longer median time from onset to coma (2.0 days vs. 0.5 days), more frequent confirmed infection (98.0% vs. 24.2%), and a higher Sequential Organ Failure Assessment (SOFA) score (6.3±1.5 vs. 3.4±0.8). These patients also exhibited lower hematoma volume (28.0±18.8 vs. 38.3±24), a lower initial National Institutes of Health Stroke Scale score (19.5±6.6 vs. 30.3±6.8), more frequent brain midline shift (59.2% vs. 27.8%), more frequent diffuse cerebral swelling (64.6% vs. 16.0%), and higher 30-day mortality (54.4% vs. 0.0%) than the patients who did awaken. Logistic multivariable regression analyses revealed that only a higher SOFA score (OR, 1.4; 95% CI, 1.079-1.767; p=0.010) and SAE (OR, 4.0; 95% CI, 1.359-6.775; p=0.001) were associated with NA events in patients with sICH. CONCLUSIONS NA in sICH patients with coma is potentially caused by secondary SAE.

Impact of Infection on Stroke Morbidity and Outcomes

Each year, millions of persons worldwide are disabled by stroke. The burden of stroke is expected to increase as a consequence of growth in our elderly population. Outcome is dependent upon limitation of secondary medical processes in the acute setting that lead to deterioration and increased long-term disability. The prevalence of infection after stroke is greater that seen in other medical conditions with similar acuity and its impact upon morbidity and mortality is substantial. Physical impairment and immune modulation are chief determinants in rate of infection after stroke. Each of these factors has been a target for therapeutic intervention. Current best practices for acute stroke management implement strategies for prevention, prompt identification, and treatment of infection. Novel therapies are currently being explored which have the opportunity to greatly minimize infectious complications following stroke. Fever commonly accompanies infection and independently influences stroke outcome. Targeted temperature management provides an additional chance to improve stroke recovery.

Significance of admission hypoalbuminemia in acute intracerebral hemorrhage

Low levels of serum albumin may increase the risk of infections and mortality in critically ill patients. We tested the hypothesis that admission hypoalbuminemia predicted infectious complications and poor outcome in subjects with acute intracerebral hemorrhage (ICH). We analyzed a single center cohort of ICH patients collected between 1994 and 2015. Pneumonia, urinary tract infection and sepsis were retrospectively identified, according to validated criteria. Serum albumin was measured on admission and hypoalbuminemia was defined as total albumin ≤3.5 g/dL. The association between albumin levels, infections, and mortality at 90 days was tested with multivariable logistic regression analyses. A total of 2010 patients were included (median age 74 years, 54.5% males) of whom 444 (22.1%) had hypoalbuminemia on admission and 763 (38%) died within 90 days. The frequency of pneumonia, urinary tract infection, and sepsis was 19.9, 15.1, and 2.7%, respectively. Hypoalbuminemic patients had lower admission Glasgow coma scale, higher frequency of intraventricular hemorrhage and were more likely to have a history of chronic kidney or liver disease. After adjustment for potential confounders, hypoalbuminemia was an independent predictor of pneumonia [odds ratio (OR) 1.76, 95% confidence interval (CI) 1.34-2.33, p < 0.001] and sepsis (OR 2.29, 95% CI 1.22-4.30, p = 0.010). Low levels of albumin were also independently associated with higher mortality at 90 days (OR 1.78, 95% CI 1.30-2.44, p < 0.001). In conclusion, early hypoalbuminemia is common and predicts poor outcome in ICH patients. Increased susceptibility to pneumonia and sepsis may be the pathophysiological mechanism underlying this association.