Progressive changes in pulmonary gas exchange during invasive respiratory support for COVID-19 associated acute respiratory failure: A retrospective study of the association with 90-day mortality

BACKGROUND

Ratio of arterial pressure of oxygen and fraction of inspired oxygen (P/F ratio) together with the fractional dead space (Vd/Vt) provides a global assessment of pulmonary gas exchange. The aim of this study was to assess the potential value of these variables to prognosticate 90-day survival in patients with COVID-19 associated ARDS admitted to the Intensive Care Unit (ICU) for invasive ventilatory support.

METHODS

In this single-center observational, retrospective study, P/F ratios and Vd/Vt were assessed up to 4 weeks after ICU-admission. Measurements from the first 2 weeks were used to evaluate the predictive value of P/F ratio and Vd/Vt for 90-day mortality and reported by the adjusted hazard ratio (HR) and 95% confidence intervals [95%CI] by Cox proportional hazard regression.

RESULTS

Almost 20,000 blood gases in 130 patients were analyzed. The overall 90-day mortality was 30% and using the data from the first ICU week, the HR was 0.85 [0.77-0.94] for every 10 mmHg increase in P/F ratio and 1.61 [1.20-2.16] for every 0.1 increase in Vd/Vt. In the second week, the HR for 90-day mortality was 0.82 [0.75-0.89] for every 10 mmHg increase in P/F ratio and 1.97 [1.42-2.73] for every 0.1 increase in Vd/Vt.

CONCLUSION

The progressive changes in P/F ratio and Vd/Vt in the first 2 weeks of invasive ventilatory support for COVID-19 ARDS were significant predictors for 90-day mortality.

Anaesthesia practice, quality indices including all-cause 30-day mortality associate to wrist fracture repositioning and surgery in Sweden: A perioperative register-based study 2018-2021

BACKGROUND

Wrist fracture is one of most common fractures frequently requiring surgical anaesthesia. There is limited information related to the anaesthetic practice and quality including 30-day mortality associated with wrist fracture in Sweden in recent years.

AIM

The aim of the present register-based study was to investigate the anaesthesia techniques used and quality indices including 30-day mortality associated with wrist fracture surgery in Sweden during the period 2018-2021.

MATERIALS AND METHODS

All fracture repositions, and surgical interventions related to wrist fracture requiring anaesthesia in patients aged >18 years registered in the Swedish Perioperative Register (SPOR) between 2018 and 2021 were included in the analysis. Information on age, ASA class, anaesthesia technique, severe operative events, most reported side-effects during recovery room stay and all-cause 30-day mortality was collected.

RESULTS

The data set included 25,147 procedures split into 14,796 females and 10,252 males (missing information n = 99) with a mean age of 52.9 ± 18.7 years and a significant age difference between females and males, 60.3 ± 15.4 and 42.2 ± 17.7 years, respectively. Mean age and ASA class increased during the study period (2018-2021), from 52.8 ± 18.6 to 54.0 ± 18.4 and ASA class 3-5 from 8.1% to 9.4% (p < .001 and p < .041, respectively). General anaesthesia (GA), GA combined with regional anaesthesia (RA), RA with or without sedation and sedation only was used in 41%, 13%, 40% and 6% of procedures, respectively, with minor changes over the study period. Pain at arrival in the recovery room (RR), (3.4%), severe pain during RR stay (2.1%), hypothermia (1.4%), postoperative nausea and vomiting (PONV) (1.2%) and urinary retention (0.5%) were the most reported side-effects during the RR stay. (RA) was associated with significantly lower occurrence of pain and PONV, and shorter RR stay, compared with GA (p < .001). The all-cause 30-day mortality was low (19 of 25,147 (0.08%)) with no differences over the period studied or anaesthetic technique.

CONCLUSION

General anaesthesia or general anaesthesia combined with regional anaesthesia are the most used anaesthetic techniques for wrist fracture procedures in Sweden. Recovery room pain, PONV, hypothermia and urinary retention is reported in overall low frequencies, with no change over the period studied, but in lower frequencies for regional anaesthesia. All-cause 30-day mortality was low; 0.08% with no change over time or between anaesthetic techniques. Thus, the present quality review based on SPOR data supports high quality of perioperative anaesthesia care.

α-Synuclein seed amplification assay as a diagnostic tool for parkinsonian disorders

INTRODUCTION

Synucleinopathies such as Parkinson's disease (PD) and multiple system atrophy (MSA) can be challenging to diagnose due to the symptom overlap with, for example, atypical parkinsonisms like progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Seed amplification assays (SAA), developed for the detection of α-synuclein (αSyn) aggregates in CSF, have been successful when used as a biomarker evaluation for synucleinopathies. In this study, we investigated the potential of this assay to not only detect αSyn seeds in CSF, but also discriminate between movement disorders.

METHODS

The αSyn-SAA was tested in a Scandinavian cohort composed of 129 CSF samples from patients with PD (n = 55), MSA (n = 27), CBD (n = 7), and PSP (n = 16), as well as healthy controls (HC, n = 24).

RESULTS

The αSyn seed amplification assay (αSyn-SAA) was able to correctly identify all PD samples as positive (sensitivity of 100%) while also discriminating the PD group from HC (70.8% specificity, p < 0.0001) and tauopathies [CBD (71% specificity) and PSP (75% specificity), p < 0.0001)]. The αSyn-SAA was also able to identify almost all MSA samples as positive for αSyn aggregation (sensitivity of 92.6%). In general, this assay is able to discriminate between the synucleinopathies and tauopathies analyzed herein (p < 0.0001) despite the overlapping symptoms in these diseases.

CONCLUSION

These findings suggest the αSyn-SAA is a useful diagnostic tool for differentiating between different parkinsonian disorders, although further optimization may be needed.

SCRN1: A cerebrospinal fluid biomarker correlating with tau in Alzheimer's disease

INTRODUCTION

Secernin-1 (SCRN1) is a neuronal protein that co-localizes with neurofibrillary tangles in Alzheimer's disease (AD), but not with tau inclusions in corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), or Pick's disease.

METHODS

We measured SCRN1 concentration in cerebrospinal fluid (CSF) using a novel mass spectrometric parallel reaction monitoring method in three clinical cohorts comprising patients with neurochemically characterized AD (n = 25) and controls (n = 28), clinically diagnosed Parkinson's disease (PD; n = 38), multiple system atrophy (MSA; n = 31), PSP (n = 20), CBD (n = 8), healthy controls (n = 37), and neuropathology-confirmed AD (n = 47).

RESULTS

CSF SCRN1 was significantly increased in AD (P < 0.01, fold change = 1.4) compared to controls (receiver operating characteristic area under the curve = 0.78) but not in CBD, PSP, PD, or MSA. CSF SCRN1 positively correlated with CSF total tau (R = 0.78, P = 1.1 × 10-13 ), phosphorylated tau181 (R = 0.64, P = 3.2 × 10-8 ), and Braak stage and negatively correlated with Mini-Mental State Examination score.

DISCUSSION

CSF SCRN1 is a candidate biomarker of AD, reflecting tau pathology.

HIGHLIGHTS

We developed a parallel reaction monitoring assay to measure secernin-1 (SCRN1) in cerebrospinal fluid (CSF). CSF SCRN1 was increased in Alzheimer's disease compared to healthy controls. CSF SCRN1 remained unchanged in Parkinson's disease, multiple system atrophy, progressive supranuclear palsy, or corticobasal degeneration compared to controls. CSF SCRN1 correlated strongly with CSF phosphorylated tau and total tau. CSF SCRN1 increased across Braak stages and negatively correlated with Mini-Mental State Examination score.

Radiological appearance and lung function six months after invasive ventilation in ICU for COVID-19 pneumonia: An observational follow-up study

BACKGROUND

Respiratory functional sequelae in COVID-19 patients admitted to the intensive care unit for invasive ventilation are sparsely reported. The aim of this study was to investigate the radiological lung appearance, lung function and their association at 6 months after hospital discharge. It was hypothesized that the degree of pathological morphology on CT scans would correlate with lung function at the time of follow-up.

METHODS AND FINDINGS

In this single-centre prospective observational study, 86 from 154 patients admitted to ICU due to COVID-19 between March 2020 and May 2021 were followed up at 6 months post discharge with computed tomography (CT) of the chest and pulmonary function tests (PFTs). The PFT results were expressed as z-scores calculated as the difference between the measured and predicted values divided by the standard deviation obtained from a reference population. Correlations were evaluated by Spearman's rho including the 95% confidence interval. Pathological changes on CT were found in 78/85 participants with fibrous parenchymal bands being the most prevalent finding (91%) followed by traction bronchiectasis (64%) and ground glass opacities (41%). Sixty-five participants performed PFTs, and a restrictive pattern was the most prevalent abnormality (34%). Diffusing capacity of the lung for carbon monoxide (DLCO) was reduced in 66% of participants. The CT severity score weakly correlated with forced vital capacity (FVC) z-score (0.295, p = 0.006), DLCO z-score (-0.231, p = 0.032) and alveolar volume (VA) z-score (0.253, p = 0.019).

CONCLUSIONS

Most patients showed persistent radiological abnormalities on CT and reduced lung volumes, impaired diffusion capacity and patterns of restrictive lung function at 6 months post discharge from the ICU. The correlations between abnormalities on CT and lung function tests were weak. Further, studies with a long-term follow-up of lung function in this group of patients are needed.

Presence of neural surface and onconeural autoantibodies in cerebrospinal fluid and serum in neurological diseases presents a potential risk for misdiagnosis

BACKGROUND AND PURPOSE

Autoantibodies have been found to contribute to pathology and are used in the diagnosis of some neurological diseases. We examined the prevalence of autoantibodies in patients with various neurological diseases and whether patients who had autoantibodies differed in age, sex, or disability from those who did not.

METHODS

We examined the prevalence of neural surface and onconeural autoantibodies in cerebrospinal fluid (CSF) and serum from patients with multiple sclerosis (n = 64), Parkinson disease plus atypical parkinsonism (n = 150), amyotrophic lateral sclerosis (n = 43), or autoimmune encephalitis (positive control; n = 7) and a healthy control group (n = 37). A total of 12 onconeural autoantibodies and six neural surface autoantibodies were tested in all participants.

RESULTS

Autoantibodies were present in all cohorts. The prevalence of autoantibodies was high (>80%) in the autoimmune encephalitis cohort but low (<20%) in all other cohorts. When comparing patients within cohorts who were positive for autoantibodies to patients who were not, there was no difference in age, sex, and disability. This was apart from the multiple sclerosis and Parkinson disease plus atypical parkinsonism cohorts, where those with positivity for autoantibodies in the CSF were significantly older.

CONCLUSIONS

The presence of the autoantibodies examined does not appear to have a substantial clinical impact within the diseases examined in this study. The presence of autoantibodies in all cohorts presents a risk for misdiagnosis when the method is used incorrectly on patients with atypical clinical presentation.

Association of Serum Brain-Derived Tau With Clinical Outcome and Longitudinal Change in Patients With Severe Traumatic Brain Injury

Importance

Blood-based measurements of total tau (T-tau) are commonly used to examine neuronal injury in patients with traumatic brain injury (TBI), but current assays do not differentiate between brain-derived tau (BD-tau) and tau produced in peripheral tissues. A novel assay for BD-tau has recently been reported that selectively quantifies nonphosphorylated tau of central nervous system origin in blood samples.

Objectives

To examine the association of serum BD-tau with clinical outcomes in patients with severe TBI (sTBI) and its longitudinal changes over 1 year.

Design, Setting, and Participants

This prospective cohort study was conducted at the neurointensive unit at the Sahlgrenska University Hospital, Gothenburg, Sweden, between September 1, 2006, and July 1, 2015. The study included 39 patients with sTBI followed up for up to 1 year. Statistical analysis was performed between October and November 2021.

Exposures

Serum BD-tau, T-tau, phosphorylated tau231 (p-tau231), and neurofilament light chain (NfL) measured on days 0, 7, and 365 after injury.

Main Outcomes and Measures

Associations of serum biomarkers with clinical outcome and longitudinal change in sTBI. Severity of sTBI was evaluated using the Glasgow Coma Scale at hospital admission, while clinical outcome was assessed with the Glasgow Outcome Scale (GOS) at 1-year follow-up. Participants were classified as having a favorable outcome (GOS score, 4-5) or unfavorable outcome (GOS score, 1-3).

Results

Among the 39 patients (median age at admission, 36 years [IQR, 22-54 years]; 26 men [66.7%]) in the study on day 0, the mean (SD) serum BD-tau level was higher among patients with unfavorable outcomes vs those with favorable outcomes (191.4 [190.8] pg/mL vs 75.6 [60.3] pg/mL; mean difference, 115.9 pg/mL [95% CI, 25.7-206.1 pg/mL]), while the other markers had smaller between-group mean differences (serum T-tau, 60.3 pg/mL [95% CI, -22.0 to 142.7 pg/mL]; serum p-tau231, 8.3 pg/mL [95% CI, -6.4 to 23.0 pg/mL]; serum NfL, -5.4 pg/mL [95% CI, -99.0 to 88.3 pg/mL]). Similar results were recorded on day 7. Longitudinally, baseline serum BD-tau concentrations showed slower decreases in the whole cohort (42.2% on day 7 [from 138.6 to 80.1 pg/mL] and 93.0% on day 365 [from 138.6 to 9.7 pg/mL]) compared with serum T-tau (81.5% on day 7 [from 57.3 to 10.6 pg/mL] and 99.0% on day 365 [from 57.3 to 0.6 pg/mL]) and p-tau231 (92.5% on day 7 [from 20.1 to 1.5 pg/mL] and 95.0% on day 365 [from 20.1 to 1.0 pg/mL]). These results did not change when considering clinical outcome, where T-tau decreased twice as fast as BD-tau in both groups. Similar results were obtained for p-tau231. Furthermore, the biomarker levels on day 365 were lower, compared with day 7, for BD-tau but not T-tau or p-tau231. Serum NfL had a different trajectory to the tau biomarkers, with levels increasing by 255.9% on day 7 compared with day 0 (from 86.8 to 308.9 pg/mL) but decreasing by 97.0% by day 365 vs day 7 (from 308.9 to 9.2 pg/mL).

Conclusions and Relevance

This study suggests that serum BD-tau, T-tau, and p-tau231 have differential associations with clinical outcome and 1-year longitudinal change in patients with sTBI. Serum BD-tau demonstrated utility as a biomarker to monitor outcomes in sTBI and can provide valuable information regarding acute neuronal damage.

Fractional spinal anesthesia and systemic hemodynamics in frail elderly hip fracture patients

Background: Systemic haemodynamic effects of intrathecal anaesthesia in an aging and frail population has not been well investigated. We examined the systemic haemodynamics of fractional spinal anaesthesia following intermittent microdosing of a local anaesthetic and an opioid. Methods: We included 15 patients aged over 65 with significant comorbidities, planned for hip fracture repair. Patients received a spinal catheter and cardiac output monitoring using the LiDCOplus system. All measurements were performed prior to start of surgery. Invasive mean arterial pressure (MAP), cardiac index (CI), systemic vascular resistance index (SVRI), heart rate and stroke volume index (SVI) were registered. Two doses of bupivacaine 2.25 mg and fentanyl 15 µg were administered with 25-minute intervals. Hypotension was defined as a fall in MAP by >30% or a MAP <65 mmHg. Results: The incidence of hypotension was 30%. Hypotensive patients (n=5) were treated with low doses of norepinephrine (0.01-0.12 µg/kg/min). MAP showed a maximum reduction of 17% at 10 minutes following the first dose. CI, systemic vascular resistance index and stroke volume index decreased by 10%, 6%, and 7%, respectively, while heart rate was unchanged over time. After the second dose, none of the systemic haemodynamic variables were affected. Conclusions: Fractional spinal anaesthesia administered prior to surgery induced a minor to moderate fall in MAP, mainly caused by a reduction in cardiac output, induced by systemic venodilation, causing a fall in venous return. Our results are contrary to the widely held belief that hypotension is mainly the result of a reduction of systemic vascular resistance.

Interactive Interventions Can Improve Hand Hygiene and Aseptic Techniques During Perioperative Care-Experience From the "Safe Hands" Project

PURPOSE

This paper evaluates a theory-driven, interactive hand hygiene (HH) intervention, the Safe Hands project, based on theories of organizational learning and culture including leadership support, dialogue and co-creation.

DESIGN

This prospective quasi-experimental study used unobtrusive overt observations to evaluate adherence to HH recommendations after implementing an infection-prevention intervention.

METHODS

The primary outcome was differences in HH practices "Before aseptic/clean procedure" (WHO moment 2), "After body fluid exposure risk" (WHO moment 3) and performance of aseptic techniques. One operating room (OR) department served as the study hospital and the other as the control hospital, both at Swedish university hospitals. Adherence to HH guidelines was measured 4 times during 2015 to 2017.

FINDINGS

The intervention site displayed a significant improvement in adherence to HH guidelines and aseptic techniques. WHO 2; from 23.8% to 36.2%, (P = .014), WHO 3; from 22.2% to 42.3%, (P = .002), and aseptic techniques; from 17.5% to 31.6%, (P = .003). No changes in adherence were identified at the control site. The use of contaminated gloves decreased post intervention at the study operating department.

CONCLUSIONS

This study shows that implementing tailored interventions that are underpinned by theories from organizational learning and culture can improve adherence to hand hygiene in a complex setting as the OR up to 6 months post-intervention. The interprofessional co-creation of standards operating procedures addressing specific care procedures and emphasizing the importance of aseptic techniques can be an acceptable and feasible way to reduce the risks of contaminating medical devices and patients during perioperative care.

The Association Between the Clinical Frailty Scale and Adverse Health Outcomes in Older Adults in Acute Clinical Settings - A Systematic Review of the Literature

Background

Frail older adults experience higher rates of adverse health outcomes. Therefore, assessing pre-hospital frailty early in the course of care is essential to identify the most vulnerable patients and determine their risk of deterioration. The Clinical Frailty Scale (CFS) is a frailty assessment tool that evaluates pre-hospital mobility, energy, physical activity, and function to generate a score that ranges from very fit to terminally ill.

Purpose

To synthesize the evidence of the association between the CFS degree and all-cause mortality, all-cause readmission, length of hospital stay, adverse discharge destination, and functional decline in patients >65 years in acute clinical settings.

Design

Systematic review with narrative synthesis.

Methods

Electronic databases (PubMed, EMBASE, CINAHL, Scopus) were searched for prospective or retrospective studies reporting a relationship between pre-hospital frailty according to the CFS and the outcomes of interest from database inception to April 2020.

Results

Our search yielded 756 articles, of which 29 studies were included in this review (15 were at moderate risk and 14 at low risk of bias). The included studies represented 26 cohorts from 25 countries (N = 44166) published between 2011 and 2020. All included studies showed that pre-hospital frailty according to the CFS is an independent predictor of all adverse health outcomes included in the review.

Conclusion

A primary purpose of the CFS is to grade clinically increased risk (i.e. risk stratification). Our results report the accumulated knowledge on the risk-predictive performance of the CFS and highlight the importance of routinely including frailty assessments, such as the CFS, to estimate biological age, improve risk assessments, and assist clinical decision-making in older adults in acute care. Further research into the potential of the CFS and whether implementing the CFS in routine practice will improve care and patients' quality of life is warranted.

Cerebrospinal Fluid Biomarkers of Synaptic Dysfunction are Altered in Parkinson's Disease and Related Disorders

BACKGROUND

Synaptic dysfunction and degeneration are central contributors to the pathogenesis and progression of parkinsonian disorders. Therefore, identification and validation of biomarkers reflecting pathological synaptic alterations are greatly needed and could be used in prognostic assessment and to monitor treatment effects.

OBJECTIVE

To explore candidate biomarkers of synaptic dysfunction in Parkinson's disease (PD) and related disorders.

METHODS

Mass spectrometry was used to quantify 15 synaptic proteins in two clinical cerebrospinal fluid (CSF) cohorts, including PD (n₁  = 51, n₂  = 101), corticobasal degeneration (CBD) (n₁  = 11, n₂  = 3), progressive supranuclear palsy (PSP) (n₁  = 22, n₂  = 21), multiple system atrophy (MSA) (n₁  = 31, n₂  = 26), and healthy control (HC) (n₁  = 48, n₂  = 30) participants, as well as Alzheimer's disease (AD) (n₂  = 23) patients in the second cohort.

RESULTS

Across both cohorts, lower levels of the neuronal pentraxins (NPTX; 1, 2, and receptor) were found in PD, MSA, and PSP, compared with HC. In MSA and PSP, lower neurogranin, AP2B1, and complexin-2 levels compared with HC were observed. In AD, levels of 14-3-3 zeta/delta, beta- and gamma-synuclein were higher compared with the parkinsonian disorders. Lower pentraxin levels in PD correlated with Mini-Mental State Exam scores and specific cognitive deficits (NPTX2; rho = 0.25-0.32, P < 0.05) and reduced dopaminergic pre-synaptic integrity as measured by DaTSCAN (NPTX2; rho = 0.29, P = 0.023). Additionally, lower levels were associated with the progression of postural imbalance and gait difficulty symptoms (All NPTX; β-estimate = -0.025 to -0.038, P < 0.05) and cognitive decline (NPTX2; β-estimate = 0.32, P = 0.021).

CONCLUSIONS

These novel findings show different alterations of synaptic proteins in parkinsonian disorders compared with AD and HC. The neuronal pentraxins may serve as prognostic CSF biomarkers for both cognitive and motor symptom progression in PD. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Sex difference in circulating soluble form of ACE2 protein in moderate and severe COVID-19 and healthy controls

Introduction

Membrane-bound angiotensin-converting enzyme-2 (ACE2) in epithelial cells is the main receptor for SARS-CoV-2. The extracellular portion of ACE2 may be shedded to plasma in which process ADAM17 (a disintegrin and metalloproteinase 17) is important. Results on the relationship between circulating levels of the soluble form of ACE2 (sACE2) and disease severity are inconclusive. This study investigates if sACE2 concentration correlates with COVID-19 severity, and whether this is affected by sex.

Materials and methods

Soluble form of ACE2 was analyzed in three groups: 104 patients (23 women and 81 men) with severe COVID-19 admitted to an intensive care unit (ICU), patients with moderate COVID-19 who required hospital care (n = 19, 4 women and 15 men), and age and sex matched healthy controls (n = 20, 4 women and 16 men). Blood samples were collected at hospital admission between 18 March 2020, and 3 May 2021, and at follow-up between 27 October 2020, and 19 October 2021. Circulating sACE2 (μg/L) was measured in EDTA plasma with a sensitive enzyme-linked immunosorbent assay. Additionally, CRP, ferritin, and lymphocyte count were analyzed during hospital stay.

Results

In total, 23 patients (22%) died in the ICU. When comparing healthy controls [mean age 58.1 (SD 11.4) years] and patients with moderate COVID-19 [mean age 61.0 (SD 13.2) years] with patients in the ICU [mean age 63.6 (SD 11.6) years], we found that sACE2 concentration decreased (70% reduction) with disease severity in men (p = 0.002) but increased 3.7-fold with severity in women (p = 0.043), suggesting a sex-related difference in how COVID-19 severity is related to sACE2 concentration. Moreover, we identified a relationship between inflammatory biomarkers and sACE2 concentration during the intensive care treatment, such that higher CRP and higher ferritin concentration correlated with lower sACE2 concentration in men.

Conclusion

The decrease in sACE2 concentration, selectively in men, in severe COVID-19 is of pathophysiological interest since men are affected more severely by the disease compared to women. Additionally, the inflammatory biomarkers, CRP and ferritin, correlated inversely with sACE2 concentration, suggesting a role in severe disease. Our findings imply that sACE2 is a possible biomarker of disease severity in a sex-specific manner.

A co-created nurse-driven catheterisation protocol can reduce bladder distension in acute hip fracture patients - results from a longitudinal observational study

Background

Urinary retention is common in elderly patients undergoing acute hip fracture surgery. Avoiding overfilling the urinary bladder is important to avoid detrusor muscle damage and associated motility problems. The aim of this study was to analyse associations between the co-creation of a nurse-driven urinary catheterisation protocol and the incidence of bladder distension in patients undergoing hip fracture surgery.

Methods

This is a single-centre implementation intervention with a retrospective longitudinal observation design, using five measures points, spanning from June 2015 to March 2020. The intervention was theory driven and the participants, together with the facilitators and researcher, co-created a nurse-driven urinary catheterisation protocol. Data were retrieved from the hip fracture register. Uni- and multivariable logistic regressions were used for analyses of changes in bladder distension and urinary volume of ≥500 ml over the years.

Results

A total of 3078 patients were included over a five-year period. The implementation intervention was associated with a reduction in the proportion of patients with bladder distension of 31.5% (95% confidence interval 26.0–37.0), from year 1 to year 5. The multivariable analysis indicated a 39% yearly reduction in bladder distension, OR 0.61 (95% confidence interval 0.57–0.64, p <  0001). There was a reduction in the proportion of patients with a bladder volume of ≥500 ml of 42.8% (95% confidence interval 36.2–49.4), from year 1 to year 5. The multivariable analysis found a 41% yearly reduction in patients with a bladder volume of ≥500 ml, OR 0.59 (95% confidence interval 0.55–0.64, p <  0.0001). The intervention was associated with improved documentation of both catheter indications and removal plans.

Conclusion

The use of predefined catheter indications and a tighter bladder scanning schedule were associated with a reduction in the incidence of both bladder distension and urine volume ≥ 500 ml in hip fracture patients. Registered nurses can play an active role in the facilitation of timely and appropriate catheter treatment in patients with hip fractures.

Trial registration

Clinical Trial Registry ISRCTN 17022695 registered retrospectively on 23 December 2021, in the end of the study, after data collection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12912-022-01057-z.

Reduction of early surgical site and other care related infections in 3553 hip fracture patients: lessons learned from the 5-year Safe Hands project

Background

Surgical site infection (SSI) after acute hip fracture surgery is a devastating complication associated with increased suffering and mortality. The aim of the study was to investigate early SSI, sepsis, pneumonia and urinary tract infections over five years, before and after the implementation of the Safe Hands project.

Methods

This was a single-centre observational study with a 5-year longitudinal design, investigating the effects of an infection-prevention intervention targeting the clinical care pathway of individuals with acute hip fracture. Statistical analyses were based on routinely collected patient outcome data comprising 3553 patients. The study conforms to the criteria of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE).

Results

The incidence of early SSIs decreased from 2.5% in years 1–2 to 1.1% in years 4–5. Similar results were observed for sepsis (2.7% to 1.3%) and urinary tract infections (14.2% to 4.2%). The multivariable regression results suggest that, for every observed year, the odds of early SSIs decreased. Male gender, procedure time, sepsis and preoperative skin damage increased the odds significantly.

Conclusions

Our preventive bundle, based on partnership between researchers, managers and clinicians and a strong commitment to change from the involved professions, appear to be effective in reducing the frequency of potentially devastating SSIs and other hospital acquired infections after hip fracture surgery. The use of external and internal facilitators was crucial to enable individual and organisational learning and overcoming barriers to improvements.

Trial registration: Clinical Trials.gov ID: NCT02983136 Registered 6 December 2016—Retrospectively registered.

Leveraging large multi-center cohorts of Alzheimer disease endophenotypes to understand the role of Klotho heterozygosity on disease risk

Two genetic variants in strong linkage disequilibrium (rs9536314 and rs9527025) in the Klotho (KL) gene, encoding a transmembrane protein, implicated in longevity and associated with brain resilience during normal aging, were recently shown to be associated with Alzheimer disease (AD) risk in cognitively normal participants who are APOE ε4 carriers. Specifically, the participants heterozygous for this variant (KL-SVHET+) showed lower risk of developing AD. Furthermore, a neuroprotective effect of KL-VSHET+ has been suggested against amyloid burden for cognitively normal participants, potentially mediated via the regulation of redox pathways. However, inconsistent associations and a smaller sample size of existing studies pose significant hurdles in drawing definitive conclusions. Here, we performed a well-powered association analysis between KL-VSHET+ and five different AD endophenotypes; brain amyloidosis measured by positron emission tomography (PET) scans (n = 5,541) or cerebrospinal fluid Aβ42 levels (CSF; n = 5,093), as well as biomarkers associated with tau pathology: the CSF Tau (n = 5,127), phosphorylated Tau (pTau181; n = 4,778) and inflammation: CSF soluble triggering receptor expressed on myeloid cells 2 (sTREM2; n = 2,123) levels. Our results found nominally significant associations of KL-VSHET+ status with biomarkers for brain amyloidosis (e.g., CSF Aβ positivity; odds ratio [OR] = 0.67 [95% CI, 0.55-0.78], β = 0.72, p = 0.007) and tau pathology (e.g., biomarker positivity for CSF Tau; OR = 0.39 [95% CI, 0.19-0.77], β = -0.94, p = 0.007, and pTau; OR = 0.50 [95% CI, 0.27-0.96], β = -0.68, p = 0.04) in cognitively normal participants, 60-80 years old, who are APOE e4-carriers. Our work supports previous findings, suggesting that the KL-VSHET+ on an APOE ε4 genotype background may modulate Aβ and tau pathology, thereby lowering the intensity of neurodegeneration and incidence of cognitive decline in older controls susceptible to AD.

Effectiveness of implementing a preventive urinary catheter care bundle in hip fracture patients

Background

Urinary catheter (UC)–associated infections are one of the most common preventable healthcare-associated infections (HAIs) and they frequently occur in older, frail populations.

Aim

The study aim was to describe the incidence of UC-associated infection in elderly patients undergoing hip fracture surgery after implementing a preventive care bundle.

Methods

A longitudinal prospective study using a before-and-after design. The bundle was theory driven and involved the co-creation of a standard operational procedure, education and practical training sessions. Prospectively collected registry data were analysed. Univariable statistics and multivariable logistic regressions were used for analyses.

Results

2,408 patients with an acute hip fracture were included into the study. There was an overall reduction in UC catheter associated-associated urinary tract infections, from 18.5% (n = 75/406) over time to 4.2% (n = 27/647). When adjusting for all identified confounders, patients in phase 4 were 74% less likely to contract an UC-associated infection (OR, 0.26; 95% CI, 0.15–0.45, p < 0.0001).

Discussion

Bundled interventions can reduce UC-associated infections substantially, even in elderly frail patients. Partnership and co-creation as implementation strategies appear to be promising in the fight against HAI.

Brace versus cast following surgical treatment of distal radial fracture: a prospective randomised study comparing quality of recovery

Background: Immobilisation following surgical treatment of distal radial fractures (DRF) is traditionally performed with a dorsal cast splint. There is an interest in changing the rigid cast to a removable brace. This can reduce the risk for cast-corrections, complications and improve recovery of function.

The aim of the study was to compare quality of recovery (QoR) between brace and traditional cast for immobilisation during the first postoperative week.

Methods: 60 patients with American Society of Anesthesiologists (ASA) physical status 1–3, scheduled for surgical treatment of DRF under a supraclavicular block (SCB) in a day-surgery setting were randomised into two groups of immobilisation post-surgery; brace (n=30) versus traditional cast (n=30). Study objectives were: differences in self-assessed QoR using the QoR-15 questionnaire, postoperative oral oxycodone consumption, perioperative time events and unplanned healthcare contacts one week postoperatively.

Results: 54 patients, 46 females/eight males were included in the analysis; 27 with brace and 27 with traditional cast. QoR-15 median scores improved significantly from baseline/preoperative to day 7 (brace p=0.001, cast p=0.001) with no differences between the two groups. The only difference found was that patients in the brace group had significantly worse pain score 24-hours post-surgery (p=0.022). No significant differences were seen in total median oxycodone consumption the first three postoperative days. No differences were found in perioperative events or unplanned healthcare contacts.

Conclusions: Brace appears to be a feasible option to traditional cast for immobilisation following surgical treatment of DRF. The early QoR was similar in both groups apart from more pain in the brace group the first 24 postoperative hours.

Neurochemical signs of astrocytic and neuronal injury in acute COVID‐19 normalizes during long‐term follow‐up

Background

Neurologic manifestations are well‐recognized features of coronavirus disease 2019 (COVID‐19). However, the longitudinal association of biomarkers reflecting CNS impact and neurological symptoms is not known. We wished to determine whether plasma biomarkers of CNS injury were associated with neurologic sequelae after COVID‐19.

Method

Patients with confirmed acute COVID‐19 were studied prospectively. Neurological symptoms were recorded during the acute phase of the disease and at six months follow‐up, and blood samples were collected longitudinally. Healthy age‐matched individuals were included as controls. We analyzed plasma concentrations of neurofilament light‐chain (NfL), glial fibrillary acidic protein (GFAp), and growth differentiation factor 15 (GDF‐15).

Result

We recruited 100 patients with mild (n = 24), moderate (n = 28), and severe (n = 48) COVID‐19 who were followed for a median of (IQR) 225 (187–262) days. In the acute phase, patients with severe COVID‐19 had higher concentrations of NfL than all other groups (all p < 0.001) and higher GFAp than controls (p < 0.001). GFAp was also significantly increased in moderate disease (p < 0.05) compared with controls. NfL (r = 0.53, p < 0.001) and GFAp (r = 0.39, p < 0.001) correlated with GDF‐15 during the acute phase. After six months, NfL and GFAp concentrations had normalized, with no persisting group differences. Despite this, 50 patients reported persistent neurological symptoms, most commonly included fatigue (n = 40), “brain‐fog” (n = 29), and changes in cognition (n = 25). We found no relation between persistent neurological symptoms and CNS injury biomarkers in the acute phase.

Conclusion

The normalization of CNS injury biomarkers in all individuals, regardless of previous disease severity or persisting neurological symptoms, indicate that post‐acute COVID‐19 neurological sequelae are not accompanied by ongoing CNS injury. Although injury biomarkers commonly increase in severe acute COVID‐19, further investigations into the causes of post‐infectious sequelae are needed.

Supraclavicular block with Mepivacaine vs Ropivacaine, their impact on postoperative pain: a prospective randomised study

BACKGROUND

Supraclavicular block (SCB) with long-acting local anaesthetic is commonly used for surgical repair of distal radial fractures (DRF). Studies have shown a risk for rebound pain when the block fades. This randomised single-centre study aimed to compare pain and opioid consumption the first three days post-surgery between SCB-mepivacaine vs. SCB-ropivacaine, with general anaesthesia (GA) as control.

METHODS

Patients (n = 90) with ASA physical status 1-3 were prospectively randomised to receive; SCB with mepivacine 1%, 25-30 ml (n = 30), SCB with ropivacaine 0.5%, 25-30 ml (n = 30) or GA (n = 30) with propofol/fentanyl/sevoflurane. Study objectives compared postoperative pain with Numeric Rating Scale (NRS) and sum postoperative Opioid Equivalent Consumption (OEC) during the first 3 days post-surgery between study-groups.

RESULTS

The three groups showed significant differences in postoperative pain-profile. Mean NRS at 24 h was significantly lower for the SCB-mepivacaine group (p = 0.018). Further both median NRS and median OEC day 0 to 3 were significanly lower in the SCB-mepivacaine group as compared to the SCB-ropivacaine group during the first three days after surgery; pain NRS 1 (IQR 0.3-3.3) and 2.7 (IQR 1.3-4.2) (p = 0.017) and OEC 30 mg (IQR 10-80) and 85 mg (IQR 45-125) (p = 0.004), respectively. The GA-group was in between both in pain NRS and median sum OEC. Unplanned healthcare contacts were highest among SCB-ropivacaine patients (39.3%) vs. SCB-mepivacaine patients (0%) and GA-patients (3.4%).

CONCLUSIONS

The potential benefit of longer duration of analgesia, associated to a long-acting local anaesthetic agent, during the early postoperative course must be put in perspective of potential worse pain progression following block resolution.

TRIAL REGISTRATION

NCT03749174 (clinicaltrials.gov, Nov 21, 2018, retrospectively registered).

Validation of the Nottingham Hip Fracture Score (NHFS) for the prediction of 30-day mortality in a Swedish cohort of hip fractures

BACKGROUND

Hip fracture is a common osteoporotic fracture with great morbidity and mortality. The utility of ASA classification is limited, as most patients are ≥ASA 3. A reliable predictor of mortality risk could support decision-making. We aimed to evaluate Nottingham hip fracture score (NHFS) for the prediction of 30-day mortality and then to recalibrate the formula converting NHFS to risk of 30-day mortality.

METHODS

All patients >60 years with surgically treated hip fracture surgery during 2015-16 were assessed. Data was extracted manually from routinely collected clinical data in registry and medical records. Discriminative performance of NHFS and ASA was assessed with C-statistics. The conversion formula from NHFS to risk of 30-day mortality was recalibrated using logistic binominal regression. Observed vs expected ratios of 30-day mortality were compared with the 2012 NHFS-formula and recalibration was performed in a split dataset.

RESULTS

1864 patients were included, with 213 deaths within 30 days. C-statistic were 0.64 for NHFS and 0.62 for ASA. Comparing expected values from the 2012-revision with our observed deaths gave a ratio of 1.37. Relating predicted levels of 30-day mortality based on 70% of our cohort vs. 30% test portion of our Swedish dataset gave a ratio of 0.97.

DISCUSSION

NHFS underestimated mortality in our cohort and showed poor discrimination. Revision of the formula based on a split dataset improved calibration. We suggest NHFS to be routinely implemented to support clinical judgements, expand preoperative assessment and escalate intraoperative monitoring.

Neurochemical signs of astrocytic and neuronal injury in acute COVID-19 normalizes during long-term follow-up

Background

Neurologic manifestations are well-recognized features of coronavirus disease 2019 (COVID-19). However, the longitudinal association of biomarkers reflecting CNS impact and neurological symptoms is not known. We sought to determine whether plasma biomarkers of CNS injury were associated with neurologic sequelae after COVID-19.

Methods

Patients with confirmed acute COVID-19 were studied prospectively. Neurological symptoms were recorded during the acute phase of the disease and at six months follow-up, and blood samples were collected longitudinally. Healthy age-matched individuals were included as controls. We analysed plasma concentrations of neurofilament light-chain (NfL), glial fibrillary acidic protein (GFAp), and growth differentiation factor 15 (GDF-15).

Findings

One hundred patients with mild (n = 24), moderate (n = 28), and severe (n = 48) COVID-19 were followed for a median (IQR) of 225 (187–262) days. In the acute phase, patients with severe COVID-19 had higher concentrations of NfL than all other groups (all p < 0·001), and higher GFAp than controls (p < 0·001). GFAp was also significantly increased in moderate disease (p < 0·05) compared with controls. NfL (r = 0·53, p < 0·001) and GFAp (r = 0·39, p < 0·001) correlated with GDF-15 during the acute phase. After six months, NfL and GFAp concentrations had normalized, with no persisting group differences. Despite this, 50 patients reported persistent neurological symptoms, most commonly fatigue (n = 40), “brain-fog” (n = 29), and changes in cognition (n = 25). We found no correlation between persistent neurological symptoms and CNS injury biomarkers in the acute phase.

Interpretation

The normalization of CNS injury biomarkers in all individuals, regardless of previous disease severity or persisting neurological symptoms, indicates that post COVID-19 neurological sequelae are not accompanied by ongoing CNS injury.

Funding

The Swedish State Support for Clinical Research, SciLifeLab Sweden, and the Knut and Alice Wallenberg Foundation have provided funding for this project.

Multi-cohort profiling reveals elevated CSF levels of brain-enriched proteins in Alzheimer's disease

OBJECTIVE

Decreased amyloid beta (Aβ) 42 together with increased tau and phospho-tau in cerebrospinal fluid (CSF) is indicative of Alzheimer's disease (AD). However, the molecular pathophysiology underlying the slowly progressive cognitive decline observed in AD is not fully understood and it is not known what other CSF biomarkers may be altered in early disease stages.

METHODS

We utilized an antibody-based suspension bead array to analyze levels of 216 proteins in CSF from AD patients, patients with mild cognitive impairment (MCI), and controls from two independent cohorts collected within the AETIONOMY consortium. Two additional cohorts from Sweden were used for biological verification.

RESULTS

Six proteins, amphiphysin (AMPH), aquaporin 4 (AQP4), cAMP-regulated phosphoprotein 21 (ARPP21), growth-associated protein 43 (GAP43), neurofilament medium polypeptide (NEFM), and synuclein beta (SNCB) were found at increased levels in CSF from AD patients compared with controls. Next, we used CSF levels of Aβ42 and tau for the stratification of the MCI patients and observed increased levels of AMPH, AQP4, ARPP21, GAP43, and SNCB in the MCI subgroups with abnormal tau levels compared with controls. Further characterization revealed strong to moderate correlations between these five proteins and tau concentrations.

INTERPRETATION

In conclusion, we report six extensively replicated candidate biomarkers with the potential to reflect disease development. Continued evaluation of these proteins will determine to what extent they can aid in the discrimination of MCI patients with and without an underlying AD etiology, and if they have the potential to contribute to a better understanding of the AD continuum.

Cardiac involvement in critically ill and mechanically ventilated patients with COVID-19 - a prospective, observational echocardiographic study

INTRODUCTION

In this prospective, observational study, we have evaluated right (RV) and left (LV) ventricular function with echocardiography and correlated it to the levels of biomarkers, hs-TNT, NT-pro-BNP, D-dimer and fibrinogen. In a subgroup, we have evaluated the effect of inhaled milrinone on RV afterload and function.

METHODS

Thirty-one ICU patients with COVID-19 in need of mechanical ventilation and norepinephrine infusion were prospectively included. Hemodynamic and respiratory variables were measured at the time of the echocardiographic examination and biomarkers were obtained on arrival at the ICU and then followed up routinely. Eight patients received inhaled aerosolized milrinone at a dose of 2.5 mg/hour.

RESULTS

The most common echocardiographic pattern was RV dilation with or without systolic dysfunction, which was found in 62% of patients. Pulmonary acceleration time was abnormal in 55% and indices of RV systolic function, such as fractional area of change, RV strain, were abnormal in 30% and 31% of patients respectively. A cardiac index of < 2.5 l/min*m² was seen in 58% of the patients. Left ventricular ejection fraction and global left ventricular strain were impaired in 10% and 16% respectively. The correlation between echocardiographic variables and cardiac biomarkers was poor. RV afterload correlated well to the levels of D-dimer. Milrinone inhalation did not improve RV function or afterload.

CONCLUSION

RV dysfunction was the most common finding. The poor correlation to cardiac biomarkers argues against extensive myocardial involvement. The lack of improvement in RV function after milrinone inhalation suggests that the most likely cause of RV dysfunction is increased RV afterload caused by pulmonary thrombosis/embolism.

The role of bone cement for the development of intraoperative hypotension and hypoxia and its impact on mortality in hemiarthroplasty for femoral neck fractures

Background and purpose - The bone cement implantation syndrome characterized by hypotension and/or hypoxia is a well-known complication in cemented arthroplasty. We studied the incidence of hypotension and/or hypoxia in patients undergoing cemented or uncemented hemiarthroplasty for femoral neck fractures and evaluated whether bone cement was an independent risk factor for postoperative mortality.Patients and methods - In this retrospective cohort study, 1,095 patients from 2 hospitals undergoing hemiarthroplasty with (n = 986) and without (n = 109) bone cementation were included. Pre-, intra-, and postoperative data were obtained from electronic medical records. Each patient was classified for grade of hypotension and hypoxia during and after prosthesis insertion according to Donaldson's criteria (Grade 1, 2, 3). After adjustments for confounders, the hazard ratio (HR) for the use of bone cement on 1-year mortality was assessed.Results - The incidence of hypoxia and/or hypotension was higher in the cemented (28%) compared with the uncemented group (17%) (p = 0.003). The incidence of severe hypotension/hypoxia (grade 2 or 3) was 6.9% in the cemented, but not observed in the uncemented group. The use of bone cement was an independent risk factor for 1-year mortality (HR 1.9, 95% CI 1.3-2.7), when adjusted for confounders.Interpretation - The use of bone cement in hemiarthroplasty for femoral neck fractures increases the incidence of intraoperative hypoxia and/or hypotension and is an independent risk factor for postoperative 1-year mortality. Efforts should be made to identify patients at risk for BCIS and alternative strategies for the management of these patients should be considered.

The influence of time-to-surgery on mortality after a hip fracture

BACKGROUND

The effect of time-to-surgery on mortality in acute hip fracture (AHF) patients has been debated and studies are inconsistent regarding from what time limit mortality starts to increase. At Sahlgrenska University Hospital/Mölndal, surgery is recommended within 24 hours leaving little time for pre-operative optimization. However, internationally the definition of early surgery varies between 24 and 48 hours and over. This retrospective study was initiated to investigate the relation between time-to-surgery and 30-day mortality.

METHOD

Data of AHF patients from January 2007 through December 2016 were collected. The variables analysed were: age, gender, American Society of Anesthesiologists physical status classification, surgical method (prosthesis or osteosynthesis) and time-to-surgery, along with 30-day mortality. Primary outcome was 30-day mortality related to time-to-surgery divided into groups. Secondary outcome was 30-day mortality related to time-to-surgery analysed hour-by-hour.

RESULTS

From 10,844 eligible patients, 9,270 patients were included into the study. Mean time-to-surgery was 19.4 hours and overall 30-day mortality was 7.6%. Adjusted Cox regression analysis revealed an increased mortality rate in patients with time-to-surgery >48 hours. In the hour-by-hour analysis, significant mortality increase was observed at 39 hours of time-to-surgery. Patients with time-to-surgery >24 hours did not have increased mortality compared to patients with time-to-surgery <24 hours.

CONCLUSION

In AHF patients, a time-to-surgery exceeding 39-48 hours was associated with increased mortality. Patients with surgeries performed before 39-48 hours did not have increased mortality and this time may, in some patients, be used for optimization prior surgery even if time-to-surgery exceeds 24 hours.

Dementia and CSF-biomarkers for Alzheimer's disease predict mortality after acute hip fracture

BACKGROUND

Mortality is high after an acute hip fracture (AHF) surgery. Are cognitive impairment and/or altered levels of Alzheimer's Disease (AD)-biomarkers in cerebrospinal fluid (CSF) predictors of mortality in AHF-patients, as retrospective studies indicate?

METHODS

Prospective single-center study including 373 AHF-patients, operated in spinal anesthesia. Cognitive status was evaluated by clinical dementia rating (CDR); CSF was analyzed for AD-biomarker concentrations (total tau (T-tau), phosphorylated tau (P-tau), amyloid beta ratio (Aβ42/Aβ40). CDR and biomarker levels were related to mortality up to one-year post-surgery, using univariate logistic regression analysis.

RESULTS

Survival analyses showed that mortality was associated to the degree of dementia. In the entire patient cohort 30-, 90-, and 365-day mortality rates were 7.2%, 15.5%, and 25.5%, respectively, but only 2.7%, 5.5%, and 12.6%, for cognitively intact vs 16.3%, 31.7%, and 42.3% for demented patients (OR = 2.2-2.8 [CI = 1.6-4.9]; P = .0001). High CSF T-tau (OR = 1.19 [CI = 1.05-1.33]; P = .004) and low Aβ42/Aβ40-ratio (OR = 0.85 [CI = 0.74-0.97]; P = .017) were associated with increased 90-day mortality. Analysis of 4 subgroups (Cognitive impairment ± and Biomarkers ±) showed significant associations of dementia and CSF biomarker concentrations to mortality after an AHF. Even cognitively intact patients presenting with abnormal AD-biomarkers showed an increased 90-day mortality which, however, was statistically insignificant.

CONCLUSIONS

Cognitive impairment and altered CSF biomarker concentrations indicative of AD pathology can predict increased mortality in patients with an AHF, and so probably even before clinical dementia diagnosis by early biomarker analysis; a notion that may have substantial clinical implications by improving perioperative treatment and postoperative rehabilitation.

Inhaled prostacyclin for the prevention of increased pulmonary vascular resistance in cemented hip hemiarthroplasty-A randomised trial

BACKGROUND

Bone cementation may cause pulmonary vasoconstriction and ventilation/perfusion abnormalities in patients undergoing cemented hip hemiarthroplasty. In this randomised trial, we tested the hypothesis that intra-operative inhalation of prostacyclin could attenuate the increase in pulmonary vascular resistance index (PVRI, primary endpoint) when compared to inhaled saline in this group of patients.

METHODS

Twenty-two patients with displaced femoral neck fractures were allocated to receive inhaled aerosolised prostacyclin (20 ng/kg/min) (n = 11) or inhaled saline (NaCl, 9 mg/mL) (n = 11). All patients received total intravenous anaesthesia and were catheterised with radial and pulmonary artery fast response thermodilution catheters, for measurements of arterial and pulmonary arterial pressures, cardiac output, right ventricular ejection fraction and effective pulmonary arterial elastance. Haemodynamic measurements were performed after induction of anaesthesia, during surgery before and immediately after bone cementation and prosthesis insertion, 10 and 20 min after insertion and during skin closure.

RESULTS

During the surgical procedure, PVRI increased both in the saline (44%, P < 0.001) and the prostacyclin (36%, P = 0.019) groups, with a less pronounced increase in the prostacyclin group (P = 0.031). Effective pulmonary arterial elastance increased both in the saline (44%, P < 0.001) and the prostacyclin groups (29%, P = 0.032), with a trend for a less pronounced increase in the prostacyclin group (P = 0.084). Right ventricular ejection fraction decreased significantly in both groups with no difference between the groups.

CONCLUSION

Inhalation of prostacyclin attenuates the increase in pulmonary vascular resistance in patients undergoing cemented hip hemiarthroplasty and could potentially attenuate/prevent haemodynamic instability induced by an increase in right ventricular afterload seen in this procedure.

The MS4A gene cluster is a key modulator of soluble TREM2 and Alzheimer's disease risk

Soluble triggering receptor expressed on myeloid cells 2 (sTREM2) in cerebrospinal fluid (CSF) has been associated with Alzheimer's disease (AD). TREM2 plays a critical role in microglial activation, survival, and phagocytosis; however, the pathophysiological role of sTREM2 in AD is not well understood. Understanding the role of sTREM2 in AD may reveal new pathological mechanisms and lead to the identification of therapeutic targets. We performed a genome-wide association study (GWAS) to identify genetic modifiers of CSF sTREM2 obtained from the Alzheimer's Disease Neuroimaging Initiative. Common variants in the membrane-spanning 4-domains subfamily A (MS4A) gene region were associated with CSF sTREM2 concentrations (rs1582763; P = 1.15 × 10-15); this was replicated in independent datasets. The variants associated with increased CSF sTREM2 concentrations were associated with reduced AD risk and delayed age at onset of disease. The single-nucleotide polymorphism rs1582763 modified expression of the MS4A4A and MS4A6A genes in multiple tissues, suggesting that one or both of these genes are important for modulating sTREM2 production. Using human macrophages as a proxy for microglia, we found that MS4A4A and TREM2 colocalized on lipid rafts at the plasma membrane, that sTREM2 increased with MS4A4A overexpression, and that silencing of MS4A4A reduced sTREM2 production. These genetic, molecular, and cellular findings suggest that MS4A4A modulates sTREM2. These findings also provide a mechanistic explanation for the original GWAS signal in the MS4A locus for AD risk and indicate that TREM2 may be involved in AD pathogenesis not only in TREM2 risk-variant carriers but also in those with sporadic disease.

Pulmonary haemodynamics and right ventricular function in cemented vs uncemented total hip arthroplasty-A randomized trial

BACKGROUND

Bone cement implantation syndrome (BCIS) is a feared complication in orthopaedic surgery with a huge impact on post-operative morbidity. In this randomized trial, we evaluated the effects of bone cement on pulmonary and systemic haemodynamics in patients receiving either cemented or uncemented hip arthroplasty for isolated femoral neck fracture.

METHODS

Twenty-two patients were randomized to receive either cemented (n = 10) or uncemented (n = 12) total hip arthroplasty. Surgery was performed under total intravenous anaesthesia in the lateral position. All patients were catheterized with radial- and pulmonary artery catheters, for continuous measurements of mean arterial pressure (MAP), pulmonary arterial pressure (PAP), cardiac output, right ventricular (RV) end-diastolic volume (RVEDV) and RV ejection fraction (RVEF). Haemodynamic measurements and blood gas analyses were performed after induction of anaesthesia, during surgery before and immediately after bone cementation and prosthesis insertion, 10 and 20 minutes after insertion and during skin closure.

RESULTS

Pulmonary vascular resistance index (PVRI) increased during and after prosthesis insertion by 45% and 20% in the cemented and uncemented group, respectively (P < 0.005). Systolic and mean PAP increased by 18% and 17% in the cemented group, which was not seen in the uncemented group (P < 0.001). There was a trend for a more pronounced fall in RVEF in the cemented group, while there were no differences in cardiac output or stroke volume between groups.

CONCLUSION

The use of bone cement in total hip arthroplasty increases pulmonary vascular resistance and the afterload of the RV with potentially negative effects on RV performance.

Prolonged vasopressor support during hip-fracture surgery is a risk factor for enhanced mortality

BACKGROUND

Hip fracture is a common injury in the elderly population and is associated with high morbidity and mortality. Intraoperative hypotension is commonly noted, and is often treated with vasopressors (VP), however, to what extent is unknown. We set out to examine retrospectively how many hip fracture-patients received VP perioperatively and further to investigate if VP treatment is connected to increased mortality.

METHOD

Data on VP treatment were captured from medical and anaesthesia journals, and if so, data were investigated to find potential confounders. Patients were divided into (a) no VP, (b) VP by injection, (c) VP by infusion <3 hours, and (d) VP by infusion ≥3 hours to achieve stratification.

RESULTS

Nine hundred and ninety-seven patients were included. About 80.4% received VP treatment. The 30-day mortality rates in subgroups were 3.6%, 5.4%, 6.4% and 19.1% respectively. The 90-day mortality rates were 6.7%, 10.3%, 11.6% and 30.3% respectively. Finally, the same patient groups had 365-day mortality rates of 12.8%, 20.0%, 23.3% and 44.9% respectively. We found a significant increase in mortality (30-90-365 days) in patients receiving VP infusion ≥3 hours, after adjusting for confounding factors. There was no increased mortality in patients treated by injection and by infusion <3 hours after adjustment for confounding factors vs untreated patients.

CONCLUSION

Vasopressor treatment is common during hip fracture surgery. Patients treated with VP infusion ≥3 hours have increased mortality, while patients treated with injections or infusion <3 hours have not. We suggest that the prolonged use of VP treatment is linked to increased mortality.

Prospective study: Long-term outcome at 12-15 years after aneurysmal subarachnoid hemorrhage

BACKGROUND

Patients with aneurysmal subarachnoid hemorrhage (aSAH) have poor outcome. Studies on outcome beyond 1 year post-aSAH are few, and late recovery is poorly investigated, initiating this prospective outcome study on patients 12-15 years after an aSAH. We hypothesized to find; functional improvement > 1 year post-ictus; increased long-term mortality in aSAH patients vs matched controls, and finally to present; predictors of long-term favorable outcome (GOS 4-5).

METHODS

We prospectively investigated patients, admitted 2000-2003 to the Sahlgrenska University Hospital, 1 year post-ictus using Glasgow Outcome Scale (GOS). The patients were revalidated 12-15 years post-aSAH by structured-telephone interviews (GOS), followed by statistical analysis.

RESULTS

A total of 158 patients were included, (women n = 114, men n = 44), with a mean age of 55 years at aSAH. Patients treated with surgical clipping had lower mortality. At the follow-up 12-15 years post-aSAH, all 103 survivors (65.2%) were categorized as having; good recovery (39.9%), moderate disability (15.2%), or severe disability (10.1%). Within the patient cohort, 23.6% improved GOS over time. Fifty-five patients died, median at 4 years post-ictus. aSAH patients had 3.5 times increased mortality 12-15 years post-ictus vs matched controls (P < .0001). Patients with favorable outcome at 1 year (67.3%, n = 101) had similar survival probability as control patients. Prognostic indicators of long-term favorable outcome were low age and high GOS at 1-year follow-up, (AUCROC, 0.79).

CONCLUSIONS

Individual functional improvement was found >1 year post-ictus. Patients with favorable outcome at 1 year had similar long-term life expectancy as the general population. Indicators of long-term favorable prognosis were low age at ictus and high GOS at 1-year follow-up.

Effects of Early Bedside Cycle Exercise on Intracranial Pressure and Systemic Hemodynamics in Critically Ill Patients in a Neurointensive Care Unit

BACKGROUND

Physiotherapy is an important part of treatment after severe brain injuries and stroke, but its effect on intracranial and systemic hemodynamics is minimally investigated. Therefore, the aim of this study was to assess the effects of an early bedside cycle exercise on intracranial and systemic hemodynamics in critically ill patients when admitted to a neurointensive care unit (NICU).

METHODS

Twenty critically ill patients suffering from brain injuries or stroke were included in this study performed in the NICU at Sahlgrenska University Hospital. One early implemented exercise session was performed using a bedside cycle ergometer for 20 min. Intracranial and hemodynamic variables were measured two times before, three times during, and two times after the bedside cycling exercise. Analyzed variables were intracranial pressure (ICP), cerebral perfusion pressure (CPP), mean arterial blood pressure (MAP), heart rate (HR), peripheral oxygen saturation (SpO₂), cardiac output (CO), stroke volume (SV), and stroke volume variation (SVV). The cycling intervention was conducted within 7 ± 5 days after admission to the NICU.

RESULTS

Cycle exercise increased MAP (p = 0.029) and SV (p = 0.003) significantly. After exercise CO, SV, MAP, and CPP decreased significantly, while no changes in HR, SVV, SpO₂, or ICP were noted when compared to values obtained during exercise. There were no differences in data obtained before versus after exercise.

CONCLUSION

Early implemented exercise with a bedside cycle ergometer, for patients with severe brain injuries or stroke when admitted to a NICU, is considered to be a clinically safe procedure.

A prospective outcome study observing patients with severe traumatic brain injury over 10-15 years

BACKGROUND

Severe traumatic brain injury (sTBI) can be divided into primary and secondary injuries. Intensive care protocols focus on preventing secondary injuries. This prospective cohort study was initiated to investigate outcome, including mortality, in patients treated according to the Lund Concept after a sTBI covering 10-15 years post-trauma.

METHODS

Patients were included during 2000-2004 when admitted to the neurointensive care unit, Sahlgrenska University Hospital. Inclusion criteria were: Glasgow coma scale score of ≤8, need for artificial ventilation and intracranial monitoring. Glasgow Outcome Scale (GOS) was used to evaluate outcome both at 1-year and 10-15 years post-trauma.

RESULTS

Ninety-five patients, (27 female and 68 male), were initially included. Both improvement and deterioration were noted between 1- and 10-15 years post-injury. Mortality rate (34/95) was higher in the studied population vs. a matched Swedish population, (Standard mortality rate (SMR) 9.5; P < 0.0001). When dividing the cohort into Good (GOS 4-5) and Poor (GOS 2-3) outcome at 1-year, only patients with Poor outcome had a higher mortality rate than the matched population (SMR 7.3; P < 0.0001). Further, good outcome (high GOS) at 1-year was associated with high GOS 10-15 years post-trauma (P < 0.0001). Finally, a majority of patients demonstrated symptoms of mental fatigue.

CONCLUSION

This indicates that patients with severe traumatic brain injury with Good outcome at 1-year have similar survival probability as a matched Swedish population and that high Glasgow outcome scale at 1-year is related to good long-term outcome. Our results further emphasise the advantage of the Lund concept.

Serum neurofilament light protein predicts clinical outcome in traumatic brain injury

Axonal white matter injury is believed to be a major determinant of adverse outcomes following traumatic brain injury (TBI). We hypothesized that measurement of neurofilament light protein (NF-L), a protein found in long white-matter axons, in blood samples, may serve as a suitable biomarker for neuronal damage in TBI patients. To test our hypotheses, we designed a study in two parts: i) we developed an immunoassay based on Single molecule array technology for quantification of NF-L in blood, and ii) in a proof-of-concept study, we tested our newly developed method on serial serum samples from severe TBI (sTBI) patients (n = 72) and controls (n = 35). We also compared the diagnostic and prognostic utility of NF-L with the established blood biomarker S100B. NF-L levels were markedly increased in sTBI patients compared with controls. NF-L at admission yielded an AUC of 0.99 to detect TBI versus controls (AUC 0.96 for S100B), and increased to 1.00 at day 12 (0.65 for S100B). Importantly, initial NF-L levels predicted poor 12-month clinical outcome. In contrast, S100B was not related to outcome. Taken together, our data suggests that measurement of serum NF-L may be useful to assess the severity of neuronal injury following sTBI.

CSF profiling of the human brain enriched proteome reveals associations of neuromodulin and neurogranin to Alzheimer's disease

Purpose

This study is part of a larger effort aiming to expand the knowledge of brain‐enriched proteins in human cerebrospinal fluid (CSF) and to provide novel insight into the relation between such proteins and different neurodegenerative diseases.

Experimental design

Here 280 brain‐enriched proteins in CSF from patients with Alzheimer's disease (AD), Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are profiled. In total, 441 human samples of ventricular CSF collected post mortem and lumbar CSF collected ante mortem are analyzed using 376 antibodies in a suspension bead array setup, utilizing a direct labelling approach.

Results

Among several proteins displaying differentiated profiles between sample groups, we focus here on two synaptic proteins, neuromodulin (GAP43) and neurogranin (NRGN). They are both found at elevated levels in CSF from AD patients in two independent cohorts, providing disease‐associated profiles in addition to verifying and strengthening previously observed patterns. Increased levels are also observed for patients for whom the AD diagnosis was not established at the time of sampling.

Conclusions and clinical relevance

These findings indicate that analyzing the brain‐enriched proteins in CSF is of particular interest to increase the understanding of the CSF proteome and its relation to neurodegenerative disorders. In addition, this study lends support to the notion that measurements of these synaptic proteins could potentially be of great relevance in future diagnostic tests for AD.

Apolipoprotein E polymorphism in aneurysmal subarachnoid haemorrhage in West Sweden

BACKGROUND AND PURPOSE

Aneurysmal subarachnoid haemorrhage (aSAH) is associated with high morbidity and mortality despite novel treatments. Genetic variability may explain outcome differences. Apolipoprotein E (ApoE) is a glycoprotein with a major role in brain lipoprotein metabolism. It has three isoforms encoded by distinct alleles: APOEε2, APOEε3 and APOEε4. The APOEε4 allele is associated with Alzheimer's disease and worse outcome after traumatic brain injury and ischaemic stroke. This prospective blinded study explored the influence of the APOEε4 polymorphism on the risk of aSAH, risk of cerebral vasospasm (CVS) and 1-year neurological outcome.

METHODS

The APOΕε4 polymorphism was analysed in 147 patients with aSAH. Allele and genotype frequencies were compared to those found in a gender- and area-matched control group of healthy individuals (n = 211). Early CVS was identified and treated according to neurointensive care unit (NICU) guidelines. Neurological deficit(s) at admittance and at 1-year follow-up visit was recorded. Neurological outcome was assessed by the National Institute of Health Stroke Scale, Barthel Index and the Extended Glasgow Outcome Scale.

RESULTS

APOEε4 and non-APOEε4 allele frequencies were similar in aSAH patients and healthy individuals. The presence of APOEε4 was not associated with the development of early CVS. We could not find an influence of the APOE polymorphism on 1-year neurological outcome between groups. Subgroup analyses of patients treated with surgical clipping vs endovascular coiling did not reveal any associations.

CONCLUSIONS

The APOEε4 polymorphism has no major influence on risk of aSAH, the occurrence of CVS or long-term neurological outcome after aSAH.

sTREM2 cerebrospinal fluid levels are a potential biomarker for microglia activity in early-stage Alzheimer's disease and associate with neuronal injury markers

TREM2 is an innate immune receptor expressed on the surface of microglia. Loss‐of‐function mutations of TREM2 are associated with increased risk of Alzheimer's disease (AD). TREM2 is a type‐1 protein with an ectodomain that is proteolytically cleaved and released into the extracellular space as a soluble variant (sTREM2), which can be measured in the cerebrospinal fluid (CSF). In this cross‐sectional multicenter study, we investigated whether CSF levels of sTREM2 are changed during the clinical course of AD, and in cognitively normal individuals with suspected non‐AD pathology (SNAP). CSF sTREM2 levels were higher in mild cognitive impairment due to AD than in all other AD groups and controls. SNAP individuals also had significantly increased CSF sTREM2 compared to controls. Moreover, increased CSF sTREM2 levels were associated with higher CSF total tau and phospho‐tau_181P, which are markers of neuronal degeneration and tau pathology. Our data demonstrate that CSF sTREM2 levels are increased in the early symptomatic phase of AD, probably reflecting a corresponding change of the microglia activation status in response to neuronal degeneration.

Association between genetic variation on chromosome 9p21 and aneurysmal subarachnoid haemorrhage

BACKGROUND AND AIM

Genetic factors play a role in susceptibility to subarachnoid haemorrhage, but little is known about which genes are involved. Recently, genome wide association studies have identified the 9p21 region as a risk locus for intracranial aneurysms (IA). The aim of the present study was to examine the possible association between 9p21 and ruptured IA--that is, aneurysmal subarachnoid haemorrhage (aSAH)--in a Swedish population. There is one study showing an association between 9p21 and arterial stiffness, and arterial stiffness plays a role in the development of hypertension. Therefore, a second aim was to investigate whether a putative association is independent of hypertension.

METHODS

The study comprised 183 patients presenting with aSAH to the Neurointensive Care Unit at Sahlgrenska University Hospital and 366 healthy, age and sex matched population based controls. As the causative functional variant in the region has not yet been identified, a 44 kbp region on 9p21 was tagged using HapMap. Six single nucleotide polymorphism (SNPs) were genotyped.

RESULTS

Two SNPs, rs10757278 and rs1333045, showed significant associations with aSAH in univariate analyses. After adjustment for hypertension as well as for smoking, the association between aSAH and rs10757278 remained significant with an OR for aSAH of 1.42 (95% CI 1.08 to 1.87; p=0.01) for the uncommon G allele.

CONCLUSIONS

These data confirm earlier results showing that 9p21 is a susceptibility locus for IA, and that this association is present in a Swedish sample restricted to ruptured IA. For the first time, it has been demonstrated that this association is independent of hypertension.

Association between factor XIII single nucleotide polymorphisms and aneurysmal subarachnoid hemorrhage

Object

Family studies have suggested a role of genetic factors in susceptibility to aneurysmal subarachnoid hemorrhage (aSAH), but the underlying genetic risk factors remain poorly defined. There is an activation of the fibrinolytic system in aSAH, and fibrinolytic markers may be useful in predicting outcome. The authors investigate associations between putative functional variants in genes of importance for fibrinolysis and aSAH and/or outcome following aSAH.

Methods

One hundred eighty-three patients presenting with aSAH at a neurointensive care unit were consecutively recruited. Two healthy controls per case, matched for age, sex, and geographic region, were randomly recruited. Outcome was assessed after 1 year according to the extended Glasgow Outcome Scale. Single nucleotide polymorphisms (SNPs) in the tissue-type plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1), thrombin activatable fibrinolysis inhibitor (TAFI), and factor XIII (FXIII) genes were investigated.

Results

Participants carrying the FXIII 34Leu allele showed an increased risk of aSAH. When adjusting for smoking and hypertension, 2 haplotypes, differing on either the FXIII Val34Leu or the Pro564Leu position, showed an association to aSAH. No significant association was observed for the tPA -7351 C > T, PAI-1 -675 4G > 5G, or TAFI Ala147Thr SNPs. No specific SNP or haplotype was associated with outcome after aSAH, whereas a weak association was observed for a tPA/PAI-1 genotype combination.

Conclusions

Polymorphisms in the FXIII gene showed association to aSAH. The finding of an increased risk of bleeding in FXIII 34Leu carriers is biologically plausible.

Changes in adipose tissue gene expression and plasma levels of adipokines and acute-phase proteins in patients with critical illness

Insulin resistance develops rapidly during critical illness. The release of adipokines from adipose tissue is thought to play a key role in the development of insulin resistance, as are elevated levels of acute-phase proteins. The aim of this study was to identify changes in adipose tissue gene expression and plasma levels of adipokines and acute-phase proteins during critical illness. From 8 patients with subarachnoidal hemorrhage, consecutive blood samples and adipose tissue biopsies were obtained at 3 time points, twice during intensive care (1-2 days [IC1] and 7-9 days after subarachnoidal hemorrhage) and once after 8 months (recovery). The patients received a continuous insulin infusion to maintain normal glucose levels reflecting insulin resistance. The DNA microarray analysis showed increased zink-alpha2 glycoprotein (ZAG) and phospholipase A2, group IIA messenger RNA levels during intensive care compared with recovery (P < .05). Real-time polymerase chain reaction confirmed the increased expression of ZAG and phospholipase A2, group IIA. Plasma levels of ZAG, serum amyloid A, and C-reactive protein were higher at 7 to 9 days after subarachnoidal hemorrhage compared with either IC1 or recovery (P = .0001); and plasma levels of retinol-binding protein 4 and adiponectin were lower at IC1 compared with recovery (P = .05). The described changes in adipose tissue gene expression and plasma levels of adipokines and acute-phase proteins may influence the development of insulin resistance during critical illness.

Apolipoprotein E polymorphism and gender difference in outcome after severe traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is one of the most common causes of death and dismal outcome among children and young adults. The morbidity and mortality differ but more aggressive monitoring and more designated neuro intensive care units have improved the results. Studies have demonstrated a connection between apolipoprotein E (APOE) genotype and outcome after TBI, but few are prospective and none is from northern Europe. APOE has three alleles: epsilon2, epsilon3 and epsilon4.

METHODS

A total of 96 patients with Glasgow coma score (GCS) < or =8 were prospectively and consecutively included. APOE genotypes were all analyzed at the same laboratory from blood samples by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

All patients were assessed at 1 year with Glasgow outcome scale extended (GOSE), National Institute of Health Stroke Scale (NIHSS) and the Barthel daily living index. The genotype was available in all patients. Twenty-six patients expressed APOE epsilon4 while 70 patients did not. Outcome demonstrated that patients with APOE epsilon4 had worse outcome vs. those lacking this allele. When subdividing patients into gender, males with APOE epsilon4 did worse, a difference not detected among female patients.

CONCLUSIONS

APOE epsilon4 correlated to worse outcome in TBI patients. We also found that males with APOE epsilon4 had poor outcome while females did not. Thus, the results indicate that genetic polymorphism may influence outcome after TBI.

Serum Glial Fibrillary Acidic Protein Is Related to Focal Brain Injury and Outcome After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Aneurysmal subarachnoid hemorrhage (aSAH) stands out from other subtypes of stroke because of the high early mortality and the risk of complications. Serum glial fibrillary acidic protein (s-GFAP) concentrations are increased after stroke. The aim of this study was to investigate whether s-GFAP could be used as a marker of brain damage and outcome after aSAH.

METHODS

Serum samples were obtained on a regular basis from 116 adults during a 2-week period after aSAH and analyzed using an enzyme-linked immunosorbent assay. The World Federation of Neurological Surgeons scale was used for neurological evaluation. Outcome was assessed after 1 year and categorized according to the Extended Glasgow Outcome Scale.

RESULTS

Increased s-GFAP levels were seen in 81 of the 116 patients. Maximum s-GFAP correlated with World Federation of Neurological Surgeons scale on arrival and on days 10 to 15 (r=0.37, P<0.001 and r=0.47, P<0.001, respectively). Furthermore, maximum s-GFAP levels were increased in the patient group with radiological signs of focal lesions acute or at 1 year, compared with the group without focal lesions (P<0.001 in both comparisons). Patients with secondary events (re-bleeding or ischemia) reached maximum levels later in the series and both maximum and final s-GFAP levels increased compared with the levels in patients without secondary events (P<0.001 in all 3 comparisons). Finally, maximum s-GFAP correlated with outcome (r=-0.48, P<0.001) and s-GFAP was an independent predictor of dichotomized outcome.

CONCLUSIONS

s-GFAP provides information about brain injury severity and outcome after aSAH, which can be useful as a complement to clinical data.

Initial CSF total tau correlates with 1-year outcome in patients with traumatic brain injury

OBJECTIVE

We investigated if tau, microtubular binding protein, in serum and ventricular CSF (vCSF) in patients with severe traumatic brain injury (TBI) during the initial posttraumatic days correlated to 1-year outcome.

METHODS

Patients with severe TBI (n = 39, Glasgow Coma Scale score <or=8) were included. We measured serum and vCSF total tau on days 0 to 14, using ELISA. vCSF total tau correlated to 1-year Extended Glasgow Outcome Scale (GOSE), the NIH Stroke Scale (NIHSS) neurologic status, and the Bartel Daily Living Index. Patients (n = 20) with normal pressure hydrocephalus (NPH) served as reference.

RESULTS

Higher levels of tau were found in TBI patients vs patients with NPH. A correlation was found between initial vCSF total tau and GOSE levels (R = 0.42, p < 0.001) but not between vCSF total tau and NIHSS or Bartel scores at 1 year. A vCSF total tau level of >2,126 pg/mL on days 2 to 3 discriminated between dead and alive (sensitivity of 100% and a specificity of 81%). A vCSF total tau level of >702 pg/mL on days 2 to 3 discriminated between bad (GOSE 1 to 4) and good (GOSE 5 to 8) outcome (sensitivity of 83% and a specificity of 69%). Patients with GOSE 1 (dead) had higher vCSF total tau levels on days 2 to 3 (p < 0.001) vs both surviving patients (GOSE 2 to 8) and those with NPH. Total tau was not detected in serum throughout the study.

CONCLUSION

The increase in ventricular CSF (vCSF) total tau probably reflects axonal damage, known to be a central pathologic mechanism in traumatic brain injury (TBI). These results suggest that vCSF total tau may be an important early biochemical neuromarker for predicting long-term outcome in patients with a severe TBI.

Prone position in mechanically ventilated patients with reduced intracranial compliance

BACKGROUND

Prone position has been used for several years to treat acute lung insufficiency, but in previous studies patients with unstable intracranial pressure (ICP) are mostly excluded. The aim of this study was to investigate if prone position is a safe and useful treatment in patients with reduced intracranial compliance.

METHODS

A consecutive, prospective pilot study of 11 patients admitted to the neuro intensive care unit (NICU) due to traumatic brain injury or intracerebral haemorrhage. ICP, cerebral perfusion pressure (CPP), heart rate (HR), mean arterial blood pressure (MABP), arterial partial pressure of oxygen (PaO(2)), arterial partial pressure of carbon dioxide (PaCO(2)), arterial oxygen saturation (SaO(2)) and respiratory system compliance were measured before, three times during and two times after the patients were placed in the prone position.

RESULTS

No significant changes were demonstrated in ICP, CPP or MABP. PaO(2) and SaO(2) were significantly increased in the prone position. HR was significantly increased in the prone position and after 10 min in the supine post-prone position and the respiratory system compliance was increased after 1 h in the supine post-prone position.

CONCLUSION

Turning NICU patients from the supine to the prone position did not influence ICP, CPP or MABP, but significantly improved patient PaO(2), SaO(2) and respiratory system compliance.

CSF –Neurofilament correlates with outcome after aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating event. Following the bleeding, a number of pathophysiological changes and clinical factors determine outcome. Not surprisingly, attempts to predict outcome based on a single factor have failed. The neurological status graded at admission to hospital and distributions of the blood on CT are the strongest predictors. There is evidence that cerebrospinal fluid (CSF) proteins may serve as markers of the extent of brain damage. The present study is focused on the light unit of neurofilament protein (NFL), previously not evaluated in aSAH. Lumbar puncture (LP), neurological grading according to World Federation of Neurological Surgeons (WFNS) and neurological examination according to the National Institute of Health Stroke Scale (NIHSS) were performed in 48 consecutive patients with aSAH 10-14 days after the hemorrhage. CSF-NFL concentrations were analyzed using an ELISA. Outcome was assessed after 1 year and categorised according to the extended Glasgow Outcome Scale (GOSE). A significant correlation between CSF-NFL and GOSE was detected at follow up after 1 year. CSF-NFL also correlated with WFNS and NIHSS on the day of the lumbar puncture. CSF-NFL is a biochemical marker of brain damage correlating to neurological status and long-term outcome after aneurysmal subarachnoid hemorrhage.