Optical coherence tomography angiography analysis methods: a systematic review and meta-analysis

Optical coherence tomography angiography (OCTA) is widely used for non-invasive retinal vascular imaging, but the OCTA methods used to assess retinal perfusion vary. We evaluated the different methods used to assess retinal perfusion between OCTA studies. MEDLINE and Embase were searched from 2014 to August 2021. We included prospective studies including ≥ 50 participants using OCTA to assess retinal perfusion in either global retinal or systemic disorders. Risk of bias was assessed using the National Institute of Health quality assessment tool for observational cohort and cross-sectional studies. Heterogeneity of data was assessed by Q statistics, Chi-square test, and I2 index. Of the 5974 studies identified, 191 studies were included in this evaluation. The selected studies employed seven OCTA devices, six macula volume dimensions, four macula subregions, nine perfusion analyses, and five vessel layer definitions, totalling 197 distinct methods of assessing macula perfusion and over 7000 possible combinations. Meta-analysis was performed on 88 studies reporting vessel density and foveal avascular zone area, showing lower retinal perfusion in patients with diabetes mellitus than in healthy controls, but with high heterogeneity. Heterogeneity was lowest and reported vascular effects strongest in superficial capillary plexus assessments. Systematic review of OCTA studies revealed massive heterogeneity in the methods employed to assess retinal perfusion, supporting calls for standardisation of methodology.

Diagnosis and management of subarachnoid haemorrhage

Aneurysmal subarachnoid haemorrhage (aSAH) presents a challenge to clinicians because of its multisystem effects. Advancements in computed tomography (CT), endovascular treatments, and neurocritical care have contributed to declining mortality rates. The critical care of aSAH prioritises cerebral perfusion, early aneurysm securement, and the prevention of secondary brain injury and systemic complications. Early interventions to mitigate cardiopulmonary complications, dyselectrolytemia and treatment of culprit aneurysm require a multidisciplinary approach. Standardised neurological assessments, transcranial doppler (TCD), and advanced imaging, along with hypertensive and invasive therapies, are vital in reducing delayed cerebral ischemia and poor outcomes. Health care disparities, particularly in the resource allocation for SAH treatment, affect outcomes significantly, with telemedicine and novel technologies proposed to address this health inequalities. This article underscores the necessity for comprehensive multidisciplinary care and the urgent need for large-scale studies to validate standardised treatment protocols for improved SAH outcomes.

Accelarated immune ageing is associated with COVID-19 disease severity

BACKGROUND

The striking increase in COVID-19 severity in older adults provides a clear example of immunesenescence, the age-related remodelling of the immune system. To better characterise the association between convalescent immunesenescence and acute disease severity, we determined the immune phenotype of COVID-19 survivors and non-infected controls.

RESULTS

We performed detailed immune phenotyping of peripheral blood mononuclear cells isolated from 103 COVID-19 survivors 3-5 months post recovery who were classified as having had severe (n = 56; age 53.12 ± 11.30 years), moderate (n = 32; age 52.28 ± 11.43 years) or mild (n = 15; age 49.67 ± 7.30 years) disease and compared with age and sex-matched healthy adults (n = 59; age 50.49 ± 10.68 years). We assessed a broad range of immune cell phenotypes to generate a composite score, IMM-AGE, to determine the degree of immune senescence. We found increased immunesenescence features in severe COVID-19 survivors compared to controls including: a reduced frequency and number of naïve CD4 and CD8 T cells (p < 0.0001); increased frequency of EMRA CD4 (p < 0.003) and CD8 T cells (p < 0.001); a higher frequency (p < 0.0001) and absolute numbers (p < 0.001) of CD28-ve CD57+ve senescent CD4 and CD8 T cells; higher frequency (p < 0.003) and absolute numbers (p < 0.02) of PD-1 expressing exhausted CD8 T cells; a two-fold increase in Th17 polarisation (p < 0.0001); higher frequency of memory B cells (p < 0.001) and increased frequency (p < 0.0001) and numbers (p < 0.001) of CD57+ve senescent NK cells. As a result, the IMM-AGE score was significantly higher in severe COVID-19 survivors than in controls (p < 0.001). Few differences were seen for those with moderate disease and none for mild disease. Regression analysis revealed the only pre-existing variable influencing the IMM-AGE score was South Asian ethnicity ([Formula: see text] = 0.174, p = 0.043), with a major influence being disease severity ([Formula: see text] = 0.188, p = 0.01).

CONCLUSIONS

Our analyses reveal a state of enhanced immune ageing in survivors of severe COVID-19 and suggest this could be related to SARS-Cov-2 infection. Our data support the rationale for trials of anti-immune ageing interventions for improving clinical outcomes in these patients with severe disease.

Landiolol and Organ Failure in Patients With Septic Shock: The STRESS-L Randomized Clinical Trial

Importance

Patients with septic shock undergo adrenergic stress, which affects cardiac, immune, inflammatory, and metabolic pathways. β-Blockade may attenuate the adverse effects of catecholamine exposure and has been associated with reduced mortality.

Objectives

To assess the efficacy and safety of landiolol in patients with tachycardia and established septic shock requiring prolonged (>24 hours) vasopressor support.

Design, Setting, and Participants

An open-label, multicenter, randomized trial involving 126 adults (≥18 years) with tachycardia (heart rate ≥95/min) and established septic shock treated for at least 24 hours with continuous norepinephrine (≥0.1 μg/kg/min) in 40 UK National Health Service intensive care units. The trial ran from April 2018 to December 2021, with early termination in December 2021 due to a signal of possible harm.

Intervention

Sixty-three patients were randomized to receive standard care and 63 to receive landiolol infusion.

Main Outcomes and Measures

The primary outcome was the mean Sequential Organ Failure Assessment (SOFA) score from randomization through 14 days. Secondary outcomes included mortality at days 28 and 90 and the number of adverse events in each group.

Results

The trial was stopped prematurely on the advice of the independent data monitoring committee because it was unlikely to demonstrate benefit and because of possible harm. Of a planned 340 participants, 126 (37%) were enrolled (mean age, 55.6 years [95% CI, 52.7 to 58.5 years]; 58.7% male). The mean (SD) SOFA score in the landiolol group was 8.8 (3.9) compared with 8.1 (3.2) in the standard care group (mean difference [MD], 0.75 [95% CI, -0.49 to 2.0]; P = .24). Mortality at day 28 after randomization in the landiolol group was 37.1% (23 of 62) and 25.4% (16 of 63) in the standard care group (absolute difference, 11.7% [95% CI, -4.4% to 27.8%]; P = .16). Mortality at day 90 after randomization was 43.5% (27 of 62) in the landiolol group and 28.6% (18 of 63) in the standard care group (absolute difference, 15% [95% CI, -1.7% to 31.6%]; P = .08). There were no differences in the number of patients having at least one adverse event.

Conclusion and Relevance

Among patients with septic shock with tachycardia and treated with norepinephrine for more than 24 hours, an infusion of landiolol did not reduce organ failure measured by the SOFA score over 14 days from randomization. These results do not support the use of landiolol for managing tachycardia among patients treated with norepinephrine for established septic shock.

Trial Registration

EU Clinical Trials Register Eudra CT: 2017-001785-14; isrctn.org Identifier: ISRCTN12600919.

Cerebrospinal Fluid Diversion for Refractory Intracranial Hypertension in Traumatic Brain Injury: A Single Center Experience

BACKGROUND

Diversion of cerebrospinal fluid (CSF) is a common neurosurgical procedure for control of intracranial pressure (ICP) in the acute phase after traumatic brain injury (TBI), where medical management is insufficient. CSF can be drained via an external ventricular drain (EVD) or, in selected patients, via a lumbar (external lumbar drain [ELD]) drainage catheter. Considerable variability exists in neurosurgical practice on their use.

METHODS

A retrospective service evaluation was completed for patients receiving CSF diversion for ICP control after TBI, from April 2015 to August 2021. Patients were included whom fulfilled local criteria deeming them suitable for either ELD/EVD. Data were extracted from patient notes, including ICP values pre/postdrain insertion and safety data including infection or clinically/radiologically diagnosed tonsillar herniation.

RESULTS

Forty-one patients were retrospectively identified (ELD = 30 and EVD = 11). All patients had parenchymal ICP monitoring. Both modalities affected statistically significant decreases in ICP, with relative reductions at 1, 6, and 24 hour pre/postdrainage (at 24-hour ELD P < 0.0001, EVD P < 0.01). Similar rates of ICP control failure, blockage and leak occurred in both groups. A greater proportion of patients with EVD were treated for CSF infection than with ELD. One event of clinical tonsillar herniation is reported, which may have been in part attributable to ELD overdrainage, but which did not result in adverse outcome.

CONCLUSIONS

The data presented demonstrate that EVD and ELD can be successful in ICP control after TBI, with ELD limited to carefully selected patients with strict drainage protocols. The findings support prospective study to formally determine the relative risk-benefit profiles of CSF drainage modalities in TBI.

SARS-CoV-2 infection is associated with anti-desmoglein 2 autoantibody detection

Post-acute cardiac sequelae, following SARS-CoV-2 infection, are well recognized as complications of COVID-19. We have previously shown the persistence of autoantibodies against antigens in skin, muscle, and heart in individuals following severe COVID-19; the most common staining on skin tissue displayed an inter-cellular cement pattern consistent with antibodies against desmosomal proteins. Desmosomes play a critical role in maintaining the structural integrity of tissues. For this reason, we analyzed desmosomal protein levels and the presence of anti-desmoglein (DSG) 1, 2, and 3 antibodies in acute and convalescent sera from patients with COVID-19 of differing clinical severity. We find increased levels of DSG2 protein in sera from acute COVID-19 patients. Furthermore, we find that DSG2 autoantibody levels are increased significantly in convalescent sera following severe COVID-19 but not in hospitalized patients recovering from influenza infection or healthy controls. Levels of autoantibody in sera from patients with severe COVID-19 were comparable to levels in patients with non-COVID-19-associated cardiac disease, potentially identifying DSG2 autoantibodies as a novel biomarker for cardiac damage. To determine if there was any association between severe COVID-19 and DSG2, we stained post-mortem cardiac tissue from patients who died from COVID-19 infection. This confirmed DSG2 protein within the intercalated discs and disruption of the intercalated disc between cardiomyocytes in patients who died from COVID-19. Our results reveal the potential for DSG2 protein and autoimmunity to DSG2 to contribute to unexpected pathologies associated with COVID-19 infection.

Reliability of Optical Coherence Tomography Angiography Retinal Blood Flow Analyses

Purpose

Investigate the association between the optical coherence tomography angiography (OCTA) metrics derived from different analysis programs to understand the comparability of studies using these different approaches.

Methods

Secondary analysis of a prospective observational study (March 2018-September 2021). Forty-four right eyes and 42 left eyes from 44 patients were included. Patients were either undergoing upper gastrointestinal surgery with a critical care stay planned or were already in the critical care unit with sepsis. OCTA scans were obtained in an ophthalmology department or critical care setting. Fourteen OCTA metrics were compared within and between the programs, and agreement was measured by Pearson's R coefficient and intraclass correlation coefficient.

Results

Correlation was highest between all Heidelberg metrics and Fractalyse (all >0.84), and lowest between Matlab skeletonized or foveal avascular zone metrics and all other measures (e.g., skeletal fractal dimension and vessel density at -0.02). Agreement between eyes was moderate to excellent in all metrics (0.60-0.90).

Conclusions

The significant variability between metrics and programs used for OCTA analysis demonstrates that they are not interchangeable and supports a recommendation for perfusion density metrics to be reported as standard.

Translational Relevance

Agreement between different OCTA analyses is variable and not interchangeable. The high agreement between non-skeletonized vessel density metrics suggests that these should be routinely reported.

Virtual Post-Intensive-Care Rehabilitation for Survivors of COVID-19: A Service Evaluation

AIM

The objective of this study is to evaluate the safety, utilisation, and effectiveness of a novel, virtual rehabilitation programme for survivors of SARS‑CoV‑2 infection (COVID-19) and intensive care admission.

METHODS

A service evaluation was performed. Adults admitted to a United Kingdom intensive care unit with COVID-19-induced respiratory failure and surviving hospital discharge were invited to an eight-week rehabilitation programme. The programme consisted of virtually delivered exercise classes and support groups led by critical care physiotherapists and follow-up nurses.

RESULTS

Thirty-eight of 76 eligible patients (50%) agreed to participate, of which 28 (74%) completed the rehabilitation programme. On completion of the rehabilitation programme, there were significant improvements in exercise capacity (one-minute sit-to-stand test; 20 stands vs. 25 stands, p < 0.001), perceived breathlessness (Medical Research Council dyspnoea scale; 3 vs. 2 p < 0.001), shoulder disability (Quick Dash; 43 vs. 19 p = 0.001), anxiety (Hospital Anxiety Depression Scale; 4 vs. 3 p = 0.021), depression (Hospital Anxiety Depression Scale; 4 vs. 2.5 p = 0.010), and psychological distress (Intensive Care Psychological Assessment Tool; 3 vs. 2 p = 0.002). No adverse events or injuries were recorded during the programme.

CONCLUSION

It is feasible to recruit and retain survivors of COVID-19-induced respiratory failure for virtual post-intensive-care rehabilitation. It appears that the virtual rehabilitation programme is safe and improves physical and psychological morbidity.

Optical coherence tomography angiography as a surrogate marker for end-organ resuscitation in sepsis: A review

Sepsis is a severe illness which results in alterations in the end organ microvascular haemodynamics and is associated with a high risk of mortality. There is currently no real-time method of monitoring microcirculatory perfusion during sepsis. Retinal microcirculation is closely linked to cerebral perfusion and may reflect systemic vascular alterations. Retinal perfusion can be assessed using the non-invasive imaging technique of optical coherence tomography angiography (OCTA). This narrative review aims to discuss the utility of using retinal imaging and OCTA in systemic illness and sepsis. OCTA can be used as a functional, non-invasive and real-time biomarker along with other haemodynamic parameters for assessing and managing patients with sepsis.

External Lumbar Drainage for Refractory Intracranial Hypertension in Traumatic Brain Injury: A Systematic Review

Considerable variation exists in the clinical practice of cerebrospinal fluid diversion for medically refractory intracranial hypertension in patients with acute traumatic brain injury (TBI), which is achievable via lumbar or ventricular drainage. This systematic review sought to compile the available evidence for the efficacy and safety of the use of lumbar drains for intracranial pressure (ICP) control.

A systematic review of the literature was performed with the search and data extraction performed by two reviewers independently in duplicate. Nine independent studies were identified, enrolling 230 patients, 159 with TBI. Efficacy for ICP control was observed across all studies, with immediate and sustained effect, reducing medical therapy requirements. Lumbar drainage with medical therapy appears effective when used alone and as an adjunct to ventricular drainage. Safety reporting varied in quality. Clinical or radiological incidents of cerebral herniation (with an unclear relationship to lumbar drainage) were observed in 14/230 patients resulting in one incident of morbidity without adverse patient outcome.

The available data is generally poor in quality and volume, but supportive of the efficacy of lumbar drainage for ICP control. Few reports of adverse outcomes are suggestive of, but are insufficient to confirm, the safety of use in the appropriate patient and clinical setting. Further large prospective observational studies are required to generate sufficient support of an acceptable safety profile.

Bayesian analysis of a systematic review of early versus late tracheostomy in ICU patients

Background

A recent systematic review and meta-analysis of RCTs of early vs late tracheostomy in mechanically ventilated patients suggest that early tracheostomy reduces the duration of ICU stay and mechanical ventilation, but does not reduce short-term mortality or ventilator-associated pneumonia (VAP). Meta-analysis of randomised trials is typically performed using a frequentist approach, and although reporting confidence intervals, interpretation is usually based on statistical significance. To provide a robust basis for clinical decision-making, we completed the search used from the previous review and analysed the data using Bayesian methods to estimate posterior probabilities of the effect of early tracheostomy on clinical outcomes.

Methods

The search was completed for RCTS comparing early vs late tracheostomy in the databases PubMed, EMBASE, and Cochrane library in June 2022. Effect estimates and 95% confidence intervals were calculated for the outcomes short-term mortality, VAP, duration of ICU stay, and mechanical ventilation. A Bayesian meta-analysis was performed with uninformative priors. Risk ratios (RRs) and standardised mean differences (SMDs) with 95% credible intervals were reported alongside posterior probabilities for any benefit (RR<1; SMD<0), a small benefit (number needed to treat, 200; SMD<–0.5), or modest benefit (number needed to treat, 100; SMD<–1).

Results

Nineteen RCTs with 3508 patients were included. Comparing patients with early vs late tracheostomy, the posterior probabilities for any benefit, small benefit, and modest benefit, respectively, were: 99%, 99%, and 99% for short-term mortality; 94%, 78%, and 51% for VAP; 97%, 43%, and 1% for duration of mechanical ventilation; and 97%, 75%, and 27% and for length of ICU stay.

Conclusions

Bayesian meta-analysis suggests a high probability that early tracheostomy compared with delayed tracheostomy has at least some benefit across all clinical outcomes considered.

SARS-CoV-2 Spike- and Nucleoprotein-Specific Antibodies Induced After Vaccination or Infection Promote Classical Complement Activation

Antibodies specific for the spike glycoprotein (S) and nucleocapsid (N) SARS-CoV-2 proteins are typically present during severe COVID-19, and induced to S after vaccination. The binding of viral antigens by antibody can initiate the classical complement pathway. Since complement could play pathological or protective roles at distinct times during SARS-CoV-2 infection we determined levels of antibody-dependent complement activation along the complement cascade. Here, we used an ELISA assay to assess complement protein binding (C1q) and the deposition of C4b, C3b, and C5b to S and N antigens in the presence of antibodies to SARS-CoV-2 from different test groups: non-infected, single and double vaccinees, non-hospitalised convalescent (NHC) COVID-19 patients and convalescent hospitalised (ITU-CONV) COVID-19 patients. C1q binding correlates strongly with antibody responses, especially IgG1 levels. However, detection of downstream complement components, C4b, C3b and C5b shows some variability associated with the subject group from whom the sera were obtained. In the ITU-CONV, detection of C3b-C5b to S was observed consistently, but this was not the case in the NHC group. This is in contrast to responses to N, where median levels of complement deposition did not differ between the NHC and ITU-CONV groups. Moreover, for S but not N, downstream complement components were only detected in sera with higher IgG1 levels. Therefore, the classical pathway is activated by antibodies to multiple SARS-CoV-2 antigens, but the downstream effects of this activation may differ depending the disease status of the subject and on the specific antigen targeted.

High generation of reactive oxygen species from neutrophils in patients with severe COVID-19

Neutrophilia and an elevated neutrophil:lymphocyte ratio are both characteristic features of severe COVID-19 infection. However, functional neutrophil responses have been poorly investigated in this setting. We utilised a novel PMA-based stimulation assay to determine neutrophil-derived reactive oxygen species (ROS) generation in patients with severe COVID-19 infection, non-COVID related sepsis and healthy study participants. ROS production was markedly elevated in COVID-19 patients with median values ninefold higher than in healthy controls and was particularly high in patients on mechanical ventilation. ROS generation correlated strongly with neutrophil count and elevated levels were also seen in patients with non-COVID related sepsis. Relative values, adjusted for neutrophil count, were high in both groups but extreme low or high values were seen in two patients who died shortly after testing, potentially indicating a predictive value for neutrophil function. Our results show that the high levels of neutrophils observed in patients with COVID-19 and sepsis exhibit functional capacity for ROS generation. This may contribute to the clinical features of acute disease and represents a potential novel target for therapeutic intervention.

Cerebrospinal Fluid Diversion for Refractory Intracranial Hypertension: A United Kingdom and Ireland Survey on Practice Variation

Introduction

Diversion of cerebrospinal fluid (CSF) in a traumatic brain injury (TBI) is an established means for achieving control of intracranial pressure (ICP), aimed at improving intracranial homeostasis. The literature and anecdotal reports suggest a variation in practice between neurosurgical centres internationally, with current guidelines advocating ventricular drainage over lumbar drainage. We sought to establish the current neurosurgical practice in the United Kingdom regarding the methods of ICP control in TBI.

Methods

A 20-point survey was distributed electronically to British and Irish neurosurgeons after ratification by the Society of British Neurological Surgeons. Questions were directed at the clinician’s opinion and experience of lumbar drain usage in patients with TBI: frequency, rationale, and experience of complications. Questions on lumbar drain usage in neurovascular patients were asked for practice comparison.

Results

Thirty-six responses from 21 neurosurgical centres were returned. Twenty-three per cent (23%) of responders reported using lumbar drains for refractory ICP in TBI patients: six units use lumbar drains and 15 do not. Three units showed partial usage, with mixed “yes/no” responses between consultants. Concerns of tonsillar herniation and familiarity with EVD were commonly given reasons against the usage of lumbar drains. Fifty-six per cent (56%) reported use in neurovascular patients.

Conclusion

This contemporary practice survey demonstrates mixed practice across the UK and within some centres. Responses and survey feedback demonstrate that the use of lumbar drains in TBI is a polarising topic. The variety of practice between and within neurosurgical units supports consideration of the prospective study of CSF diversion methods for control of refractory ICP in patients with TBI.

Sugar or salt ("SOS"): A protocol for a UK multicentre randomised trial of mannitol and hypertonic saline in severe traumatic brain injury and intracranial hypertension

Hyperosmolar solutions are widely used to treat raised intracranial pressure following severe traumatic brain injury. Although mannitol has historically been the most frequently administered, hypertonic saline solutions are increasingly being used. However, definitive evidence regarding their comparative effectiveness is lacking. The Sugar or Salt Trial is a UK randomised, allocation concealed open label multicentre pragmatic trial designed to determine the clinical and cost-effectiveness of hypertonic saline compared with mannitol in the management of patients with severe traumatic brain injury. Patients requiring intensive care unit admission and intracranial pressure monitoring post-traumatic brain injury will be allocated at random to receive equi-osmolar boluses of either mannitol or hypertonic saline following failure of routine first-line measures to control intracranial pressure. The primary outcome for the study will be the Extended Glasgow Outcome Scale assessed at six months after randomisation. Results will inform current clinical practice in the routine use of hyperosmolar therapy as well as assess the impact of potential side effects. Pre-planned longer term clinical and cost effectiveness analyses will further inform the use of these treatments.

Namilumab or infliximab compared with standard of care in hospitalised patients with COVID-19 (CATALYST): a randomised, multicentre, multi-arm, multistage, open-label, adaptive, phase 2, proof-of-concept trial

BACKGROUND

Dysregulated inflammation is associated with poor outcomes in COVID-19. We aimed to assess the efficacy of namilumab (a granulocyte-macrophage colony stimulating factor inhibitor) and infliximab (a tumour necrosis factor inhibitor) in hospitalised patients with COVID-19, to prioritise agents for phase 3 trials.

METHODS

In this randomised, multicentre, multi-arm, multistage, parallel-group, open-label, adaptive, phase 2, proof-of-concept trial (CATALYST), we recruited patients (aged ≥16 years) admitted to hospital with COVID-19 pneumonia and C-reactive protein (CRP) concentrations of 40 mg/L or greater, at nine hospitals in the UK. Participants were randomly assigned with equal probability to usual care or usual care plus a single intravenous dose of namilumab (150 mg) or infliximab (5 mg/kg). Randomisation was stratified by care location within the hospital (ward vs intensive care unit [ICU]). Patients and investigators were not masked to treatment allocation. The primary endpoint was improvement in inflammation, measured by CRP concentration over time, analysed using Bayesian multilevel models. This trial is now complete and is registered with ISRCTN, 40580903.

FINDINGS

Between June 15, 2020, and Feb 18, 2021, we screened 299 patients and 146 were enrolled and randomly assigned to usual care (n=54), namilumab (n=57), or infliximab (n=35). For the primary outcome, 45 patients in the usual care group were compared with 52 in the namilumab group, and 29 in the usual care group were compared with 28 in the infliximab group. The probabilities that the interventions were superior to usual care alone in reducing CRP concentration over time were 97% for namilumab and 15% for infliximab; the point estimates for treatment-time interactions were -0·09 (95% CI -0·19 to 0·00) for namilumab and 0·06 (-0·05 to 0·17) for infliximab. 134 adverse events occurred in 30 (55%) of 55 patients in the namilumab group compared with 145 in 29 (54%) of 54 in the usual care group. 102 adverse events occurred in 20 (69%) of 29 patients in the infliximab group compared with 112 in 17 (50%) of 34 in the usual care group. Death occurred in six (11%) patients in the namilumab group compared with ten (19%) in the usual care group, and in four (14%) in the infliximab group compared with five (15%) in the usual care group.

INTERPRETATION

Namilumab, but not infliximab, showed proof-of-concept evidence for reduction in inflammation-as measured by CRP concentration-in hospitalised patients with COVID-19 pneumonia. Namilumab should be prioritised for further investigation in COVID-19.

FUNDING

Medical Research Council.

Regular use of proton-pump inhibitors and risk of stroke: a population-based cohort study and meta-analysis of randomized-controlled trials

BACKGROUND

Although randomized controlled trials (RCTs) have suggested a non-significant increased risk of stroke among proton pump inhibitor (PPI) users, the association has not been confirmed. We evaluated the association between regular use of PPIs and incident stroke and identified population groups at high net risk.

METHODS

This is a prospective analysis of 492,479 participants free of stroke from the UK biobank. Incident stroke was identified through linkage to hospital admission and death registries using the International Classification of Diseases (ICD)-10 codes (I60, I61, I63, and I64). We evaluated hazard ratios (HRs) adjusting for demographic factors, lifestyle habits, prevalent comorbidities, concomitant use of medications, and indications of PPIs. We assessed the risk differences (RDs) according to the baseline Framingham Stroke Risk Score. In the meta-analysis, we searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (from 1988 to 1 June 2020) for randomized trials comparing PPIs with other interventions, placebo, or no treatment on stroke risk. Results were combined using a fix-effect meta-analysis (Mantel-Haenszel method).

RESULTS

We documented 5182 incident strokes over 3,935,030 person-years of follow-up. Regular PPI users had a 16% higher risk of stroke than non-users (HR 1.16, 95% CI 1.06 to 1.27). The estimated effect was similar to our meta-analysis of nine RCTs (case/participants 371/26,642; RR 1.22, 95% CI 1.00 to 1.50; quality of evidence: moderate). The absolute effect of PPI use on stroke increased with the baseline Framingham Stroke Risk Score, with an RD of 1.34‰, 3.32‰, 4.83‰, and 6.28‰ over 5 years for the lowest, quartile 2, quartile 3, and the highest quartile, respectively.

CONCLUSIONS

Regular use of PPIs was associated with an increased risk of stroke, with a higher absolute risk observed in individuals with high baseline stroke risk. Physicians should therefore exercise caution when prescribing PPIs. An assessment of the underlying stoke risk is recommended for individualized use of PPIs.

CATALYST trial protocol: a multicentre, open-label, phase II, multiarm trial for an early and accelerated evaluation of the potential treatments for COVID-19 in hospitalised adults

INTRODUCTION

Severe SARS-CoV-2 infection is associated with a dysregulated immune response. Inflammatory monocytes and macrophages are crucial, promoting injurious, proinflammatory sequelae. Immunomodulation is, therefore, an attractive therapeutic strategy and we sought to test licensed and novel candidate drugs.

METHODS AND ANALYSIS

The CATALYST trial is a multiarm, open-label, multicentre, phase II platform trial designed to identify candidate novel treatments to improve outcomes of patients hospitalised with COVID-19 compared with usual care. Treatments with evidence of biomarker improvements will be put forward for larger-scale testing by current national phase III platform trials. Hospitalised patients >16 years with a clinical picture strongly suggestive of SARS-CoV-2 pneumonia (confirmed by chest X-ray or CT scan, with or without a positive reverse transcription PCR assay) and a C reactive protein (CRP) ≥40 mg/L are eligible. The primary outcome measure is CRP, measured serially from admission to day 14, hospital discharge or death. Secondary outcomes include the WHO Clinical Progression Improvement Scale as a principal efficacy assessment.

ETHICS AND DISSEMINATION

The protocol was approved by the East Midlands-Nottingham 2 Research Ethics Committee (20/EM/0115) and given urgent public health status; initial approval was received on 5 May 2020, current protocol version (V.6.0) approval on 12 October 2020. The MHRA also approved all protocol versions. The results of this trial will be disseminated through national and international presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBERS

EudraCT2020-001684-89, ISRCTN40580903.

Individual factors including age, BMI and heritable factors underlie temperature variation in sickness and in health: an observational, multi-cohort study

Background

Aging affects immunity, potentially altering fever response to infection. We assess effects of biological variables on basal temperature, and during COVID-19 infection, proposing an updated temperature threshold for older adults ≥65 years.

Methods

Participants were from 4 cohorts: 1 089 unaffected adult TwinsUK volunteers; 520 adults with emergency admission to a London hospital with RT-PCR confirmed SARS-CoV-2 infection; 757 adults with emergency admission to a Birmingham hospital with RT-PCR confirmed SARS-CoV-2 infection and 3 972 adult community-based COVID Symptom Study participants self-reporting a positive RT-PCR test. Heritability was assessed using saturated and univariate ACE models; mixed-effect and multivariable linear regression examined associations between temperature, age, sex, and body mass index (BMI); multivariable logistic regression examined associations between fever (≥37.8°C) and age; receiver operating characteristic (ROC) analysis was used to identify temperature threshold for adults ≥ 65 years.

Results

Among unaffected volunteers, lower BMI (p = .001), and increasing age (p < .001) was associated with lower basal temperature. Basal temperature showed a heritability of 47% (95% confidence interval 18%–57%). In COVID-19+ participants, increasing age was associated with lower temperatures in Birmingham and community-based cohorts (p < .001). For each additional year of age, participants were 1% less likely to demonstrate a fever ≥37.8°C (OR 0.99; p < .001). Combining healthy and COVID-19+ participants, a temperature of 37.4°C in adults ≥65 years had similar sensitivity and specificity to 37.8°C in adults <65 years for discriminating infection.

Conclusions

Aging affects temperature in health and acute infection, with significant heritability, indicating genetic factors contribute to temperature regulation. Our observations suggest a lower threshold (37.4°C/97.3°F) for identifying fever in older adults ≥65 years.

Establishing the prevalence of common tissue-specific autoantibodies following severe acute respiratory syndrome coronavirus 2 infection

Coronavirus 19 (COVID-19) has been associated with both transient and persistent systemic symptoms that do not appear to be a direct consequence of viral infection. The generation of autoantibodies has been proposed as a mechanism to explain these symptoms. To understand the prevalence of autoantibodies associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we investigated the frequency and specificity of clinically relevant autoantibodies in 84 individuals previously infected with SARS-CoV-2, suffering from COVID-19 of varying severity in both the acute and convalescent setting. These were compared with results from 32 individuals who were on the intensive therapy unit (ITU) for non-COVID reasons. We demonstrate a higher frequency of autoantibodies in the COVID-19 ITU group compared with non-COVID-19 ITU disease control patients and that autoantibodies were also found in the serum 3-5 months post-COVID-19 infection. Non-COVID patients displayed a diverse pattern of autoantibodies; in contrast, the COVID-19 groups had a more restricted panel of autoantibodies including skin, skeletal muscle and cardiac antibodies. Our results demonstrate that respiratory viral infection with SARS-CoV-2 is associated with the detection of a limited profile of tissue-specific autoantibodies, detectable using routine clinical immunology assays. Further studies are required to determine whether these autoantibodies are specific to SARS-CoV-2 or a phenomenon arising from severe viral infections and to determine the clinical significance of these autoantibodies.

Outcomes following acute poor-grade aneurysmal subarachnoid bleed - Is early definitive treatment better than delayed management?

BACKGROUND/OBJECTIVE

Patients with poor-grade subarachnoid bleed (World Federation of Neurosurgical Societies grades 4-5) often improve their neurocognitive function months after their ictus. However, it is essential to explore the timing of intervention and its impact on long-term outcome. We compared the long-term outcomes between immediate management within 24 h and delayed management after 24 h in patients following poor-grade subarachnoid bleed.

METHODS

This was a retrospective population-based study, including patients with poor-grade subarachnoid bleed who received definitive management between 1 January 2011 and 31 December 2016 in a large tertiary neurocritical care unit. The primary outcome was adjusted odds ratio of favourable outcome (Glasgow Outcome Scale 4-5) for survivors at 12 months following discharge, as measured by the Glasgow Outcome Scale. The secondary outcomes included adjusted odds ratio of a favourable outcome at discharge, 3 months and 6 months following discharge and survival rate at 28 days, 3 months, 6 months and 12 months following haemorrhage.

RESULTS

A total of 111 patients were included in this study: 53 (48%) received immediate management and 58 (52%) received delayed management. The mean time delay from referral to intervention was 14.9 ± 5.8 h in immediate management patients, compared to 79.6 ± 106.1 h in delayed management patients. At 12 months following discharge, the adjusted odds ratio for favourable outcome in immediate management versus delayed management patients was 0.96 (confidence interval (CI) = 0.17, 5.39; p = 0.961). At hospital discharge, 3 months and 6 months, the adjusted odds ratio for favourable outcome was 3.85 (CI = 1.38, 10.73; p = 0.010), 1.04 (CI = 0.22, 5.00; p = 0.956) and 0.98 (CI = 0.21, 4.58; p = 0.982), respectively. There were no differences in survival rate between the groups at 28 days, 3 months, 6 months and 12 months (71.7% in immediate management group vs. 82.8% in delayed management group at 12 months, p = 0.163).

CONCLUSIONS

Immediate management and delayed management after poor-grade subarachnoid bleed are associated with similar morbidity and mortality at 12 months. Therefore, delaying intervention in poor-grade patients may be a reasonable approach, especially if time is needed to plan the procedure or stabilise the patient adequately.

Ensemble learning for poor prognosis predictions: A case study on SARS-CoV-2

OBJECTIVE

Risk prediction models are widely used to inform evidence-based clinical decision making. However, few models developed from single cohorts can perform consistently well at population level where diverse prognoses exist (such as the SARS-CoV-2 [severe acute respiratory syndrome coronavirus 2] pandemic). This study aims at tackling this challenge by synergizing prediction models from the literature using ensemble learning.

MATERIALS AND METHODS

In this study, we selected and reimplemented 7 prediction models for COVID-19 (coronavirus disease 2019) that were derived from diverse cohorts and used different implementation techniques. A novel ensemble learning framework was proposed to synergize them for realizing personalized predictions for individual patients. Four diverse international cohorts (2 from the United Kingdom and 2 from China; N = 5394) were used to validate all 8 models on discrimination, calibration, and clinical usefulness.

RESULTS

Results showed that individual prediction models could perform well on some cohorts while poorly on others. Conversely, the ensemble model achieved the best performances consistently on all metrics quantifying discrimination, calibration, and clinical usefulness. Performance disparities were observed in cohorts from the 2 countries: all models achieved better performances on the China cohorts.

DISCUSSION

When individual models were learned from complementary cohorts, the synergized model had the potential to achieve better performances than any individual model. Results indicate that blood parameters and physiological measurements might have better predictive powers when collected early, which remains to be confirmed by further studies.

CONCLUSIONS

Combining a diverse set of individual prediction models, the ensemble method can synergize a robust and well-performing model by choosing the most competent ones for individual patients.

The prognostic value of resting-state EEG in acute post-traumatic unresponsive states

Accurate early prognostication is vital for appropriate long-term care decisions after traumatic brain injury. While measures of resting-state EEG oscillations and their network properties, derived from graph theory, have been shown to provide clinically useful information regarding diagnosis and recovery in patients with chronic disorders of consciousness, little is known about the value of these network measures when calculated from a standard clinical low-density EEG in the acute phase post-injury. To investigate this link, we first validated a set of measures of oscillatory network features between high-density and low-density resting-state EEG in healthy individuals, thus ensuring accurate estimation of underlying cortical function in clinical recordings from patients. Next, we investigated the relationship between these features and the clinical picture and outcome of a group of 18 patients in acute post-traumatic unresponsive states who were not following commands 2 days+ after sedation hold. While the complexity of the alpha network, as indexed by the standard deviation of the participation coefficients, was significantly related to the patients' clinical picture at the time of EEG, no network features were significantly related to outcome at 3 or 6 months post-injury. Rather, mean relative alpha power across all electrodes improved the accuracy of outcome prediction at 3 months relative to clinical features alone. These results highlight the link between the alpha rhythm and clinical signs of consciousness and suggest the potential for simple measures of resting-state EEG band power to provide a coarse snapshot of brain health for stratification of patients for rehabilitation, therapy and assessments of both covert and overt cognition.

99 Heritability of Temperature and the Effects of Ageing on Temperature Regulation: An Observational Multi-Cohort Study

Introduction

Ageing affects homeostasis and immunosenescence, resulting in aberrant fever and immune responses to infection in older adults. This study assesses heritability of basal temperature and explores effects of ageing on basal temperature and temperature in response to SARS-CoV-2 infection.

Methods

Observational study using multiple cohorts. Participants: (a) Twin volunteers: 1089 healthy adults enrolled in Twins-UK, mean age 59 (17); tympanic temperature measurements; (b) Community-based: 3972 adults using the COVID Symptom Study mobile application, age 43 (13); self-reported test-positive for SARS-CoV-2 infection; self-reported temperature measurements; (c) Hospitalised: cohorts of 520 and 757 adult patients with emergency admission to two teaching hospitals between 01/03/2020–04/05/2020, age 62 (17) and 68 (17) respectively; RT-PCR-confirmed SARS-CoV-2 infection.

Analysis

(a) heritability analysed using saturated and ACE univariate models; linear mixed-effect model for associations between basal temperature and age, sex and BMI. (b&c) multivariable linear regression for associations between temperature and age, sex and BMI; multivariable logistic regression for associations between fever(>/= 37.8°C) and age, sex and BMI.

Results

Basal temperature in twins demonstrated 50% heritability (95%CI[42–57%]). In healthy twin, community-based and hospitalised cohorts, increasing age is associated with lower temperatures, and increasing BMI with higher temperatures: (a) Twins (age:p < 0.001; BMI:p = 0.002); (b) Community-based (age: p < 0.001; BMI: p < 0.001); (c) Hospitalised (1st hospital: age: p = 0.106; BMI: p = 0.033; 2nd hospital: age: p < 0.001; BMI: p = 0.010). Increasing age was negatively and BMI positively associated with fever (1st hospital: Age: OR = 0.99, p = 0.033; BMI: OR = 1.00, p = 0.045; 2nd hospital: Age: OR = 0.99, p = 0.010; BMI: OR 1.02, p = 0.038).

Conclusions

Heritability of basal temperature suggests a genetic component to thermoregulation. Associations observed between increasing age and lower temperatures and higher BMI and higher temperatures are important in understanding effects of ageing and obesity on basal temperature and the fever response. In older adults, findings have important implications for defining fever thresholds and diagnosing infections, including SARS-CoV-2.

Critical care management of the patient with an acute ischaemic stroke

Acute ischaemic stroke is a leading cause of morbidity and mortality worldwide. In the UK alone, there are more than 100 000 strokes per year, causing 38 000 deaths. While the incidence remains high, there has been significant medical progress in reducing mortality following a stroke. Admission of patients to specialised stroke units has led to an improvement in clinical outcomes, but the role of intensive care is less well defined. This article reviews the current critical care management and neuro-therapeutic options after an acute ischaemic stroke.

Covert Speech Comprehension Predicts Recovery From Acute Unresponsive States

OBJECTIVE

Patients with traumatic brain injury who fail to obey commands after sedation-washout pose one of the most significant challenges for neurological prognostication. Reducing prognostic uncertainty will lead to more appropriate care decisions and ensure provision of limited rehabilitation resources to those most likely to benefit. Bedside markers of covert residual cognition, including speech comprehension, may reduce this uncertainty.

METHODS

We recruited 28 patients with acute traumatic brain injury who were 2 to 7 days sedation-free and failed to obey commands. Patients heard streams of isochronous monosyllabic words that built meaningful phrases and sentences while their brain activity via electroencephalography (EEG) was recorded. In healthy individuals, EEG activity only synchronizes with the rhythm of phrases and sentences when listeners consciously comprehend the speech. This approach therefore provides a measure of residual speech comprehension in unresponsive patients.

RESULTS

Seventeen and 16 patients were available for assessment with the Glasgow Outcome Scale Extended (GOSE) at 3 months and 6 months, respectively. Outcome significantly correlated with the strength of patients' acute cortical tracking of phrases and sentences (r > 0.6, p < 0.007), quantified by inter-trial phase coherence. Linear regressions revealed that the strength of this comprehension response (beta = 0.603, p = 0.006) significantly improved the accuracy of prognoses relative to clinical characteristics alone (eg, Glasgow Coma Scale [GCS], computed tomography [CT] grade).

INTERPRETATION

A simple, passive, auditory EEG protocol improves prognostic accuracy in a critical period of clinical decision making. Unlike other approaches to probing covert cognition for prognostication, this approach is entirely passive and therefore less susceptible to cognitive deficits, increasing the number of patients who may benefit. ANN NEUROL 2021;89:646-656.

Assembly Line ICU: what the Long Shops taught us about managing surge capacity for COVID-19

Objectives

To safely expand and adapt the normal workings of a large critical care unit in response to the COVID-19 pandemic.

Methods

In April 2020, UK health systems were challenged to expand critical care capacity rapidly during the first wave of the COVID-19 pandemic so that they could accommodate patients with respiratory and multiple organ failure. Here, we describe the preparation and adaptive responses of a large critical care unit to the oncoming burden of disease. Our changes were similar to the revolution in manufacturing brought about by ‘Long Shops’ of 1853 when Richard Garrett and Sons of Leiston started mass manufacture of traction engines. This innovation broke the whole process into smaller parts and increased productivity. When applied to COVID-19 preparations, an assembly line approach had the advantage that our ICU became easily scalable to manage an influx of additional staff as well as the increase in admissions. Healthcare professionals could be replaced in case of absence and training focused on a smaller number of tasks.

Results

Compared with the equivalent period in 2019, the ICU provided 30.9% more patient days (2599 to 3402), 1845 of which were ventilated days (compared with 694 in 2019, 165.8% increase) while time from first referral to ICU admission reduced from 193.8±123.8 min (±SD) to 110.7±76.75 min (±SD). Throughout, ICU maintained adequate capacity and also accepted patients from neighbouring hospitals. This was done by managing an additional 205 doctors (70% increase), 168 nurses who had previously worked in ICU and another 261 nurses deployed from other parts of the hospital (82% increase).

Our large tertiary hospital ensured a dedicated non-COVID ICU was staffed and equipped to take regional emergency referrals so that those patients requiring specialist surgery and treatment were treated throughout the COVID-19 pandemic.

Conclusions

We report how the challenge of managing a huge influx of patients and redeployed staff was met by deconstructing ICU care into its constituent parts. Although reported from the largest colocated ICU in the UK, we believe that this offers solutions to ICUs of all sizes and may provide a generalisable model for critical care pandemic surge planning.

Retinal blood flow in critical illness and systemic disease: a review

BACKGROUND

Assessment and maintenance of end-organ perfusion are key to resuscitation in critical illness, although there are limited direct methods or proxy measures to assess cerebral perfusion. Novel non-invasive methods of monitoring microcirculation in critically ill patients offer the potential for real-time updates to improve patient outcomes.

MAIN BODY

Parallel mechanisms autoregulate retinal and cerebral microcirculation to maintain blood flow to meet metabolic demands across a range of perfusion pressures. Cerebral blood flow (CBF) is reduced and autoregulation impaired in sepsis, but current methods to image CBF do not reproducibly assess the microcirculation. Peripheral microcirculatory blood flow may be imaged in sublingual and conjunctival mucosa and is impaired in sepsis. Retinal microcirculation can be directly imaged by optical coherence tomography angiography (OCTA) during perfusion-deficit states such as sepsis, and other systemic haemodynamic disturbances such as acute coronary syndrome, and systemic inflammatory conditions such as inflammatory bowel disease.

CONCLUSION

Monitoring microcirculatory flow offers the potential to enhance monitoring in the care of critically ill patients, and imaging retinal blood flow during critical illness offers a potential biomarker for cerebral microcirculatory perfusion.

COVID-19-related intracranial imaging findings: a large single-centre experience

AIM

To describe the neuroradiological changes in patients with coronavirus disease 2019 (COVID-19).

MATERIALS AND METHODS

A retrospective review was undertaken of 3,403 patients who were confirmed positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and admitted to Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK between 1 March 2020 and 31 May 2020, and who underwent neuroimaging. Abnormal brain imaging was evaluated in detail and various imaging patterns on magnetic resonance imaging MRI were identified.

RESULTS

Of the 3,403 patients with COVID-19, 167 (4.9%) had neurological signs or symptoms warranting neuroimaging. The most common indications were delirium (44/167, 26%), focal neurology (37/167, 22%), and altered consciousness (34/167, 20%). Neuroimaging showed abnormalities in 23% of patients, with MRI being abnormal in 20 patients and computed tomography (CT) in 18 patients. The most consistent neuroradiological finding was microhaemorrhage with a predilection for the splenium of the corpus callosum (12/20, 60%) followed by acute or subacute infarct (5/20, 25%), watershed white matter hyperintensities (4/20, 20%), and susceptibility changes on susceptibility-weighted imaging (SWI) in the superficial veins (3/20, 15%), acute haemorrhagic necrotising encephalopathy (2/20, 10%), large parenchymal haemorrhage (2/20, 10%), subarachnoid haemorrhage (1/20, 5%), hypoxic–ischaemic changes (1/20, 5%), and acute disseminated encephalomyelitis (ADEM)-like changes (1/20, 5%).

CONCLUSION

Various imaging patterns on MRI were observed including acute haemorrhagic necrotising encephalopathy, white matter hyperintensities, hypoxic-ischaemic changes, ADEM-like changes, and stroke. Microhaemorrhages were the most common findings. Prolonged hypoxaemia, consumption coagulopathy, and endothelial disruption are the likely pathological drivers and reflect disease severity in this patient cohort.

Multicenter longitudinal cross-sectional study comparing effectiveness of serratus anterior plane, paravertebral and thoracic epidural for the analgesia of multiple rib fractures

Background

There is a paucity of data comparing effectiveness of various techniques for pain management of traumatic rib fractures. This study compared the quality of analgesia provided by serratus anterior plane (SAP) catheters against thoracic epidural (TEA) or paravertebral catheters (PA) in patients with multiple traumatic rib fractures (MRFs).

Methods

354 patients who received either SAP, TEA or PA at two tertiary referral major trauma centers in the UK were included (2016–2018). Primary outcome were change in inspiratory volumes and pain scores. Secondary outcomes included in-hospital mortality, along with the length of stay in hospital and critical care. Data were analyzed using linear, log-binomial and negative binomial regression models.

Main results

Across all blocks, there was a mean (SD) increase in inspiratory volume postblock of 789.4 mL (479.7). Ninety-eight per cent of all participants reported moderate/severe pain prior to regional analgesia, which was reduced to 34% postblock. There was no significant difference in the change in inspiratory volume or pain scores between the TEA, PA or SAP groups. Overall crude mortality was 13.2% (95% CI 7.8% to 18.7%). In an adjusted analysis and compared with TEA, in-hospital mortality was similar between groups (relative risk (RR) 0.4, 95% CI 0.1 to 1.0) and (RR 0.5, 95% CI 0.2 to 1.6) for SAP and PA, respectively.

Conclusion

SAP, TEA and PA all appear to offer the ability to reduce pain scores and improve respiratory function.

Analgesia of Patients with Multiple Rib Fractures in Critical Care: A Survey of Healthcare Professionals in the UK

Introduction

Good analgesia has been shown to reduce the risk of pneumonia, chronic pain, and mortality in patients with multiple rib fractures (MRFs). This survey explores the current analgesic practice in the UK, protocol use, barriers to provision, and physician preferences.

Materials and methods

A web-based survey was distributed nationally to an enriched cohort of clinicians working in UK trauma units with an interest in MRF management.

Results

Seventy-nine healthcare professionals responded. A third (31.4%) reported that their department had a rib fracture pain protocol, 52.9% did not, and 15.7% were unsure. Significantly more respondents reported adequate pain control when a hospital protocol was present compared to when not (χ², p < 0.01). Inadequate analgesia, a poor cough, and inability to breathe deeply were the commonest complications reported by 81.4, 78.6, and 65.7%, respectively. Patient-controlled analgesia (PCA) was the most commonly used form of analgesia (38.6%) followed by thoracic epidural (TEA) (30.0%) and continuous opioid infusion (18.6%). However, TEA was the preferred method of analgesia among respondents (37.1%) followed by serratus block (21.4%), paravertebral block (17.1%), and PCA (14.3%).

Discussion

There is considerable variation among physicians in their current use of analgesic modalities, with opiate-based methods predominating despite a physician preference for regional techniques. Thoracic epidurals are preferred by physicians but of limited use as a result of contraindications, time pressures, and staff skill mix. Pain control is reported to be better handled when protocols are present. Further research focusing on currently utilized regional techniques is required in order to produce a validated standardized national protocol that is informed by the current practice, the evidence base, and limitations to service provision.

Key messages

There is considerable variation among physicians in their current use of analgesic modalities. Opiate-based methods dominate for thoracic trauma despite a physician preference for regional techniques, which can be challenging in this cohort due to contraindications, staff skill mix, and time pressures. Inadequate analgesia is common but is better managed when pain management protocols are available.

How to cite this article

Beard L, Holt B, Snelson C, Parcha C, Smith FG, Veenith T. Analgesia of Patients with Multiple Rib Fractures in Critical Care: A Survey of Healthcare Professionals in the UK. Indian J Crit Care Med 2020;24(3):184–189.

Optical coherence tomography (OCT) in unconscious and systemically unwell patients using a mobile OCT device: a pilot study

OBJECTIVE

This study aims to evaluate the feasibility of retinal imaging in critical care using a novel mobile optical coherence tomography (OCT) device. The Heidelberg SPECTRALIS FLEX module (Heidelberg Engineering, Heidelberg, Germany) is an OCT unit with a boom arm, enabling ocular OCT assessment in less mobile patients.

DESIGN

We undertook an evaluation of the feasibility of using the SPECTRALIS FLEX for undertaking ocular OCT images in unconscious and critically ill patients.

SETTING

This study was conducted in the critical care unit of a large tertiary referral unit in the United Kingdom.

PARTICIPANTS

13 systemically unwell patients admitted to the critical care unit were purposively sampled to enable evaluation in patients with a range of clinical states.

OUTCOME MEASURES

The primary outcome was the feasibility of acquiring clinically interpretable OCT scans on a consecutive series of patients. The standardised scanning protocol included macula-focused OCT, OCT optic nerve head (ONH), OCT angiography (OCTA) of the macula and ONH OCTA.

RESULTS

OCT images from 13 patients were attempted. The success rates of each scan type are 84% for OCT macula, 76% for OCT ONH, 56% for OCTA macula and 36% for OCTA ONH. The overall mean success rate of scans per patient was 64% (95% CI 46% to 81%). Clinicians reported clinical value in 100% scans which were successfully obtained, including both ruling in and ruling out relevant ocular complications such as corneal thinning, macular oedema and optic disc swelling. The most common causes of failure to achieve clinically interpretable scans were inadequately sustained OCT alignment in delirious patients and a compromised ocular surface due to corneal exposure.

CONCLUSIONS

This prospective evaluation indicates the feasibility and potential clinical value of the SPECTRALIS FLEX OCT system on the critical care unit. Portable OCT systems have the potential to bring instrument-based ophthalmic assessment to critically ill patients, enabling detection and micron-level monitoring of ocular complications.

Association Between Hospital Volume and Mortality in Status Epilepticus: A National Cohort Study

OBJECTIVES

In various medical and surgical conditions, research has found that centers with higher patient volumes have better outcomes. This relationship has not previously been explored for status epilepticus. This study sought to examine whether centers that see higher volumes of patients with status epilepticus have lower in-hospital mortality than low-volume centers.

DESIGN

Cohort study, using 2010-2015 data from the nationwide Case Mix Programme database of the U.K.'s Intensive Care National Audit and Research Centre.

SETTING

Greater than 90% of ICUs in United Kingdom, Wales, and Northern Ireland.

PATIENTS

Twenty-thousand nine-hundred twenty-two adult critical care admissions with a primary or secondary diagnosis of status epilepticus or prolonged seizure.

INTERVENTIONS

Annual hospital status epilepticus admission volume.

MEASUREMENTS AND MAIN RESULTS

We used multiple logistic regression to evaluate the association between hospital annual status epilepticus admission volume and in-hospital mortality. Hospital volume was modeled as a nonlinear variable using restricted cubic splines, and generalized estimating equations with robust SEs were used to account for clustering by institution. There were 2,462 in-hospital deaths (11.8%). There was no significant association between treatment volume and in-hospital mortality for status epilepticus (p = 0.54). This conclusion was unchanged across a number of subgroup and sensitivity analyses, although we lacked data on seizure duration and medication use. Secondary analyses suggest that many high-risk patients were already transferred from low- to high-volume centers.

CONCLUSIONS

We find no evidence that higher volume centers are associated with lower mortality in status epilepticus overall. It is likely that national guidelines and local pathways in the United Kingdom allow efficient patient transfer from smaller centers like district general hospitals to provide satisfactory patient care in status epilepticus. Future research using more granular data should explore this association for the subgroup of patients with refractory and superrefractory status epilepticus.

The weekend effect in status epilepticus: a national cohort study

Higher mortality following admission to hospital at the weekend has been reported for several conditions. It is unclear whether this variation is due to differences in patients or their care. Status epilepticus mandates hospital admission and usually critical care: its study might provide new insights into the nature of any weekend effect. We studied 20,922 adults admitted to UK critical care with status epilepticus from 2010 to 2015. We used multiple logistic regression to evaluate the association between weekend admission and in-hospital mortality, comparing university hospitals with other hospitals. There were 2462 in-hospital deaths (12%). There was no difference in mortality after weekend admission to university hospitals, adjusted odds ratio (95%CI) 0.99 (0.84-1.16), p = 0.89. Mortality was less after weekend admission than after admissions Monday to Friday in hospitals not associated with a university, adjusted odds ratio (95%CI) 0.74 (0.64-0.87), p = 0.0001. There is no evidence that adults admitted to UK critical care at the weekend in status epilepticus are more likely to die than similar patients admitted during the week.

A comparison of earlier and enhanced rehabilitation of mechanically ventilated patients in critical care compared to standard care (REHAB): study protocol for a single-site randomised controlled feasibility trial

BACKGROUND

Mortality from critical illness is improving, but survivors suffer from prolonged weakness and psychological and cognitive impairments. Maximising the recovery after critical illness has been highlighted as a research priority, especially in relation to an ageing population who present with higher rates of pre-morbid disability. Small studies have shown that starting rehabilitation early within the intensive care unit (ICU) improves short-term outcomes. Systematic reviews have highlighted the need for robust multicentre randomised controlled trials with longer term follow-up.

METHODS

The study design is a randomised controlled study to explore the feasibility of providing earlier and enhanced rehabilitation to mechanically ventilated patients at high risk of ICU-acquired weakness within the ICU. The rehabilitation intervention involves a structured programme, with progression along a functionally based mobility protocol according to set safety criteria. The overall aim of the intervention is to commence mobilisation at an earlier time point in the patient's illness and increase mobility of the patient through their recovery trajectory. Participants will be randomised to enhanced rehabilitation or standard care, with the aim of recruiting at least 100 patients over 16 months. The trial design will assess recruitment and consent rates from eligible patients, compliance with the intervention, and assess a range of possible outcome measures for use in a definitive trial, with follow-up continuing for 12 months post hospital discharge.

DISCUSSION

This study will evaluate the feasibility of providing an earlier and enhanced rehabilitation intervention to mechanically ventilated patients in critical care. We will identify strengths and weaknesses of the proposed protocol and the utility and characteristics of the outcome measures. The results from this study will inform the design of a phase III multicentre trial of enhanced rehabilitation for critically ill adults.

TRIAL REGISTRATION

ISRCTN90103222, 13/08/2015; retrospectively registered.

Systematic review of statins in sepsis: There is no evidence of dose response

Objectives:

Sepsis is a common cause of morbidity and mortality and is associated with significant costs to the healthcare organizations. We performed a systematic review and meta-analysis to assess whether high or low-dose statin therapy improved mortality in patients with sepsis.

Methods:

The trials analyzed in this study were multicenter or single center randomized control studies using statins for sepsis in a hospital setting. The patients included were adults with suspected or confirmed infection.

Interventions:

This study found eight randomized controlled trials where participants were given either a statin or placebo daily for 14–28 days, the duration of their illness, or until their death or discharge, which ever occurred first.

Primary and Secondary Outcomes Measured:

This meta-analysis measured the effect of statin therapy on in hospital and 28 days mortality.

Results:

In unselected patients, there was no demonstrable difference in the 28 days mortality (relative risk [RR] 0.88 95% confidence interval [CI], 0.70–1.12 and P = 0.16). There was also no significant difference between statin versus placebo for in-hospital mortality (RR 0.98 95% CI, 0.85–1.14 P = 0.36). When the studies where divided into low-dose and high-dose groups, there were no statistically significant differences for in-hospital mortality between low-dose statin versus placebo for (RR 0.81 CI 0.44–1.49 P = 0.27) or high-dose statin versus placebo (RR 0.99 95% CI 0.85–1.16, P = 0.28). There was no significant difference in adverse effects between the high- and low-dose groups.

Conclusions:

In this meta-analysis, we found that the use of statins did not significantly improve either in-hospital mortality or 28-day mortality in patients with sepsis. In the low-dose group, there were fewer quality multicenter studies; hence, conclusions based on the results of this subgroup are limited.

Tracheostomy in special groups of critically ill patients: Who, when, and where?

Tracheostomy is one of the most common procedures undertaken in critically ill patients. It offers many theoretical advantages over translaryngeal intubation. Recent evidence in a heterogeneous group of critically ill patients, however, has not demonstrated a benefit for tracheostomy, in terms of mortality, length of stay in Intensive Care Unit (ICU), or incidence of ventilator-associated pneumonia. It may be a beneficial intervention in articular subsets of ICU patients. In this article, we will focus on the evidence for the timing of tracheostomy and its effect on various subgroups of patients in critical care.

Age influences the predictive value of Acute Physiology and Chronic Health Evaluation II and Intensive Care National Audit and Research Centre scoring models in patients admitted to Intensive Care Units after in-hospital cardiac arrest

INTRODUCTION

Outcomes following in-hospital cardiac arrest (IHCA) are generally poor though different patient populations may benefit to different degrees from admission to Intensive Care Units (ICUs). Risk stratification algorithms may be useful in identifying patients who are most likely to benefit from ICU admission and so may aid allocation of this scarce resource. We aimed to compare the performance of the Acute Physiology and Chronic Health Evaluation II (APACHE II) and Intensive Care National Audit and Research Centre (ICNARC) scoring systems in predicting outcome following ICU admission after IHCA in younger (≤69 years) and older (≥70 years) patients.

MATERIALS AND METHODS

We performed a retrospective observational study in two adult ICUs from January 2006 to February 2010 inclusive. Patients were divided into younger (≤69 years) and older (≥70 years) patients. The primary outcome measures were acute hospital mortality and area under the curve (AUC) calculation for receiver operating characteristic (ROC) analysis.

RESULTS

Two hundred and sixty-one adult consecutive adult patients admitted following IHCA. Hospital mortality was 58.6%. ROC analysis demonstrated that ICNARC was more accurate than APACHE II in predicting acute hospital outcomes in the adult population (AUC 0.734 vs. 0.706). Both scoring systems performed weaker when predicting outcomes in younger patients compared to older patients (ICNARC AUC 0.655 vs. 0.810; APACHE II AUC 0.660 vs. 0.759).

DISCUSSION

Both APACHE II and ICNARC predict outcome well in older patients. In younger patients, their value is less clear, and so they must be used with caution.

Amyloid imaging with carbon 11-labeled Pittsburgh compound B for traumatic brain injury

OBJECTIVES

To image amyloid deposition in patients with traumatic brain injury (TBI) using carbon 11-labeled Pittsburgh Compound B ([11C]PiB) positron emission tomography (PET) and to validate these findings using tritium-labeled PiB ([3H]PiB) autoradiography and immunocytochemistry in autopsy-acquired tissue.

DESIGN, SETTING, AND PARTICIPANTS

In vivo PET at tertiary neuroscience referral center and ex vivo immunocytochemistry of autopsy-acquired brain tissue from a neuropathology archive. [11C]PiB PET was used to image amyloid deposition in 11 controls (median [range] age, 35 [24-60] years) and in 15 patients (median [range] age, 33 [21-50] years) between 1 and 361 days after a TBI. [3H]PiB autoradiography and immunocytochemistry for β-amyloid (Aβ) and β-amyloid precursor protein in brain tissue were obtained from separate cohorts of 16 patients (median [range] age, 46 [21-70] years) who died between 3 hours and 56 days after a TBI and 7 controls (median [range] age, 61 [29-71] years) who died of other causes.

MAIN OUTCOMES AND MEASURES

We quantified the [11C]PiB distribution volume ratio and standardized uptake value ratio in PET images. The distribution volume ratio and the standardized uptake value ratio were measured in cortical gray matter, white matter, and multiple cortical and white matter regions of interest, as well as in striatal and thalamic regions of interest. We examined [3H]PiB binding and Aβ and β-amyloid precursor protein immunocytochemistry in autopsy-acquired brain tissue.

RESULTS

Compared with the controls, the patients with TBI showed significantly increased [11C]PiB distribution volume ratios in cortical gray matter and the striatum (corrected P < .05 for both), but not in the thalamus or white matter. Increases in [11C]PiB distribution volume ratios in patients with TBI were seen across most cortical subregions, were replicated using comparisons of standardized uptake value ratios, and could not be accounted for by methodological confounders. Autoradiography revealed [3H]PiB binding in neocortical gray matter, in regions where amyloid deposition was demonstrated by immunocytochemistry; white matter showed Aβ and β-amyloid precursor protein by immunocytochemistry, but no [3H]PiB binding. No plaque-associated amyloid immunoreactivity or [3H]PiB binding was seen in cerebellar gray matter in autopsy-acquired tissue from either controls or patients with TBI, although 1 sample of cerebellar tissue from a patient with TBI showed amyloid angiopathy in meningeal vessels.

CONCLUSIONS AND RELEVANCE

[11C]PiB shows increased binding following TBI. The specificity of this binding is supported by neocortical [3H]PiB binding in regions of amyloid deposition in the postmortem tissue of patients with TBI. [11C]PiB PET could be valuable in imaging amyloid deposition following TBI.