Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
100
result(s) for
"Brealey, David A."
Sort by:
Optimal intensive care outcome prediction over time using machine learning
by
Beale, Richard
,
Brett, Stephen J.
,
Meiring, Christopher
in
Analysis
,
Artificial intelligence
,
Biology and Life Sciences
2018
Prognostication is an essential tool for risk adjustment and decision making in the intensive care unit (ICU). Research into prognostication in ICU has so far been limited to data from admission or the first 24 hours. Most ICU admissions last longer than this, decisions are made throughout an admission, and some admissions are explicitly intended as time-limited prognostic trials. Despite this, temporal changes in prognostic ability during ICU admission has received little attention to date. Current predictive models, in the form of prognostic clinical tools, are typically derived from linear models and do not explicitly handle incremental information from trends. Machine learning (ML) allows predictive models to be developed which use non-linear predictors and complex interactions between variables, thus allowing incorporation of trends in measured variables over time; this has made it possible to investigate prognosis throughout an admission.
This study uses ML to assess the predictability of ICU mortality as a function of time. Logistic regression against physiological data alone outperformed APACHE-II and demonstrated several important interactions including between lactate & noradrenaline dose, between lactate & MAP, and between age & MAP consistent with the current sepsis definitions. ML models consistently outperformed logistic regression with Deep Learning giving the best results. Predictive power was maximal on the second day and was further improved by incorporating trend data. Using a limited range of physiological and demographic variables, the best machine learning model on the first day showed an area under the receiver-operator characteristic curve (AUC) of 0.883 (σ = 0.008), compared to 0.846 (σ = 0.010) for a logistic regression from the same predictors and 0.836 (σ = 0.007) for a logistic regression based on the APACHE-II score. Adding information gathered on the second day of admission improved the maximum AUC to 0.895 (σ = 0.008). Beyond the second day, predictive ability declined.
This has implications for decision making in intensive care and provides a justification for time-limited trials of ICU therapy; the assessment of prognosis over more than one day may be a valuable strategy as new information on the second day helps to differentiate outcomes. New ML models based on trend data beyond the first day could greatly improve upon current risk stratification tools.
Journal Article
Once-Daily Single-Inhaler Triple versus Dual Therapy in Patients with COPD
by
Pascoe, Steven J
,
Criner, Gerard J
,
Martinez, Fernando J
in
Acetylcholine receptors (muscarinic)
,
Administration, Inhalation
,
Adrenergic beta-Agonists - administration & dosage
2018
The frequency of COPD exacerbations during treatment with a triple inhaler — delivering a long-acting beta-agonist (LABA), a long-acting muscarinic antagonist (LAMA), and an inhaled glucocorticoid — was compared with that with a LABA–LAMA or LABA–inhaled glucocorticoid.
Journal Article
Ancient reindeer mitogenomes reveal island-hopping colonisation of the Arctic archipelagos
by
Hansen, Brage Bremset
,
Rasmussen, Jacob Agerbo
,
Ellegaard, Martin Rene
in
631/181
,
631/181/757
,
631/208
2024
Climate warming at the end of the last glacial period had profound effects on the distribution of cold-adapted species. As their range shifted towards northern latitudes, they were able to colonise previously glaciated areas, including remote Arctic islands. However, there is still uncertainty about the routes and timing of colonisation. At the end of the last ice age, reindeer/caribou (Rangifer tarandus) expanded to the Holarctic region and colonised the archipelagos of Svalbard and Franz Josef Land. Earlier studies have proposed two possible colonisation routes, either from the Eurasian mainland or from Canada via Greenland. Here, we used 174 ancient, historical and modern mitogenomes to reconstruct the phylogeny of reindeer across its whole range and to infer the colonisation route of the Arctic islands. Our data shows a close affinity among Svalbard, Franz Josef Land and Novaya Zemlya reindeer. We also found tentative evidence for positive selection in the mitochondrial gene ND4, which is possibly associated with increased heat production. Our results thus support a colonisation of the Eurasian Arctic archipelagos from the Eurasian mainland and provide some insights into the evolutionary history and adaptation of the species to its High Arctic habitat.
Journal Article
Levosimendan for the Prevention of Acute Organ Dysfunction in Sepsis
by
McAuley, Daniel F
,
Al-Beidh, Farah
,
McNamee, James J
in
Body weight
,
Calcium
,
Clinical trials
2016
In a randomized trial, over 500 patients with sepsis received levosimendan or placebo in addition to usual care. Levosimendan did not result in a lower likelihood of organ dysfunction or lower mortality.
Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection
1
and is a leading cause of death worldwide. Septic shock is the most severe form of the condition and results in circulatory and metabolic abnormalities.
2
Persisting hypotension despite adequate fluid resuscitation is due to a combination of profound vasodilatation, vascular hyporeactivity to catecholamines, and myocardial depression.
3
Although catecholamines are the recommended first-line therapy for septic shock,
4
high doses of administered catecholamines and high levels of circulating catecholamines are associated with poor outcomes and severe side effects, including myocardial injury and peripheral ischemia.
5
–
7
Levosimendan is . . .
Journal Article
FULFIL Trial: Once-Daily Triple Therapy for Patients with Chronic Obstructive Pulmonary Disease
by
Pascoe, Steven J.
,
Zhu, Chang-Qing
,
Locantore, Nicholas
in
Administration, Inhalation
,
Androstadienes - therapeutic use
,
Benzyl Alcohols - therapeutic use
2017
Abstract
Rationale
Randomized data comparing triple therapy with dual inhaled corticosteroid (ICS)/long-acting β2-agonist (LABA) therapy in patients with chronic obstructive pulmonary disease (COPD) are limited.
Objectives
We compared the effects of once-daily triple therapy on lung function and health-related quality of life with twice-daily ICS/LABA therapy in patients with COPD.
Methods
The FULFIL (Lung Function and Quality of Life Assessment in Chronic Obstructive Pulmonary Disease with Closed Triple Therapy) trial was a randomized, double-blind, double-dummy study comparing 24 weeks of once-daily triple therapy (fluticasone furoate/umeclidinium/vilanterol 100 μg/62.5 μg/25 μg; ELLIPTA inhaler) with twice-daily ICS/LABA therapy (budesonide/formoterol 400 μg/12 μg; Turbuhaler). A patient subgroup remained on blinded treatment for up to 52 weeks. Co–primary endpoints were change from baseline in trough FEV1 and in St. George’s Respiratory Questionnaire (SGRQ) total score at Week 24.
Measurements and Main Results
In the intent-to-treat population (n = 1,810) at Week 24 for triple therapy (n = 911) and ICS/LABA therapy (n = 899), mean changes from baseline in FEV1 were 142 ml (95% confidence interval [CI], 126 to 158) and −29 ml (95% CI, −46 to −13), respectively, and mean changes from baseline in SGRQ scores were −6.6 units (95% CI, −7.4 to −5.7) and −4.3 units (95% CI, −5.2 to −3.4), respectively. For both endpoints, the between-group differences were statistically significant (P < 0.001). There was a statistically significant reduction in moderate/severe exacerbation rate with triple therapy versus dual ICS/LABA therapy (35% reduction; 95% CI, 14–51; P = 0.002). The safety profile of triple therapy reflected the known profiles of the components.
Conclusions
These results support the benefits of single-inhaler triple therapy compared with ICS/LABA therapy in patients with advanced COPD.
Clinical trial registered with www.clinicaltrials.gov (NCT02345161).
Journal Article
Preoperative intravenous iron to treat anaemia before major abdominal surgery (PREVENTT): a randomised, double-blind, controlled trial
by
Clevenger, Ben
,
Butcher, Anna
,
Swinson, Rebecca
in
Abdomen
,
Abdomen - surgery
,
Abdominal surgery
2020
Preoperative anaemia affects a high proportion of patients undergoing major elective surgery and is associated with poor outcomes. We aimed to test the hypothesis that intravenous iron given to anaemic patients before major open elective abdominal surgery would correct anaemia, reduce the need for blood transfusions, and improve patient outcomes.
In a double-blind, parallel-group randomised trial, we recruited adult participants identified with anaemia at preoperative hospital visits before elective major open abdominal surgery at 46 UK tertiary care centres. Anaemia was defined as haemoglobin less than 130 g/L for men and 120 g/L for women. We randomly allocated participants (1:1) via a secure web-based service to receive intravenous iron or placebo 10–42 days before surgery. Intravenous iron was administered as a single 1000 mg dose of ferric carboxymaltose in 100 mL normal saline, and placebo was 100 mL normal saline, both given as an infusion over 15 min. Unblinded study personnel prepared and administered the study drug; participants and other clinical and research staff were blinded to treatment allocation. Coprimary endpoints were risk of the composite outcome of blood transfusion or death, and number of blood transfusions from randomisation to 30 days postoperatively. The primary analysis included all randomly assigned patients with data available for the primary endpoints; safety analysis included all randomly assigned patients according to the treatment received. This study is registered, ISRCTN67322816, and is closed to new participants.
Of 487 participants randomly assigned to placebo (n=243) or intravenous iron (n=244) between Jan 6, 2014, and Sept 28, 2018, complete data for the primary endpoints were available for 474 (97%) individuals. Death or blood transfusion occurred in 67 (28%) of the 237 patients in the placebo group and 69 (29%) of the 237 patients in the intravenous iron group (risk ratio 1·03, 95% CI 0·78–1·37; p=0·84). There were 111 blood transfusions in the placebo group and 105 in the intravenous iron group (rate ratio 0·98, 95% CI 0·68–1·43; p=0·93). There were no significant differences between the two groups for any of the prespecified safety endpoints.
Preoperative intravenous iron was not superior to placebo to reduce need for blood transfusion when administered to patients with anaemia 10–42 days before elective major abdominal surgery.
UK National Institute of Health Research Health Technology Assessment Program.
Journal Article
Surgery versus cast immobilisation for adults with a bicortical fracture of the scaphoid waist (SWIFFT): a pragmatic, multicentre, open-label, randomised superiority trial
2020
Scaphoid fractures account for 90% of carpal fractures and occur predominantly in young men. The use of immediate surgical fixation to manage this type of fracture has increased, despite insufficient evidence of improved outcomes over non-surgical management. The SWIFFT trial compared the clinical effectiveness of surgical fixation with cast immobilisation and early fixation of fractures that fail to unite in adults with scaphoid waist fractures displaced by 2 mm or less.
This pragmatic, parallel-group, multicentre, open-label, two-arm, randomised superiority trial included adults (aged 16 years or older) who presented to orthopaedic departments of 31 hospitals in England and Wales with a clear bicortical fracture of the scaphoid waist on radiographs. An independent remote randomisation service used a computer-generated allocation sequence with randomly varying block sizes to randomly assign participants (1:1) to receive either early surgical fixation (surgery group) or below-elbow cast immobilisation followed by immediate fixation if non-union of the fracture was confirmed (cast immobilisation group). Randomisation was stratified by whether or not there was displacement of either a step or a gap of 1–2 mm inclusive on any radiographic view. The primary outcome was the total patient-rated wrist evaluation (PRWE) score at 52 weeks after randomisation, and it was analysed on an available case intention-to-treat basis. This trial is registered with the ISRCTN registry, ISRCTN67901257, and is no longer recruiting, but long-term follow-up is ongoing.
Between July 23, 2013, and July 26, 2016, 439 (42%) of 1047 assessed patients (mean age 33 years; 363 [83%] men) were randomly assigned to the surgery group (n=219) or to the cast immobilisation group (n=220). Of these, 408 (93%) participants were included in the primary analysis (203 participants in the surgery group and 205 participants in the cast immobilisation group). 16 participants in the surgery group and 15 participants in the cast immobilisation group were excluded because of either withdrawal, no response, or no follow-up data at 6, 12, 26, or 52 weeks. There was no significant difference in mean PRWE scores at 52 weeks between the surgery group (adjusted mean 11·9 [95% CI 9·2–14·5]) and the cast immobilisation group (14·0 [11·3 to 16·6]; adjusted mean difference −2·1 [95% CI −5·8 to 1·6], p=0·27). More participants in the surgery group (31 [14%] of 219 participants) had a potentially serious complication from surgery than in the cast immobilisation group (three [1%] of 220 participants), but fewer participants in the surgery group (five [2%]) had cast-related complications than in the cast immobilisation group (40 [18%]). The number of participants who had a medical complication was similar between the two groups (four [2%] in the surgery group and five [2%] in the cast immobilisation group).
Adult patients with scaphoid waist fractures displaced by 2 mm or less should have initial cast immobilisation, and any suspected non-unions should be confirmed and immediately fixed with surgery. This treatment strategy will help to avoid the risks of surgery and mostly limit the use of surgery to fixing fractures that fail to unite.
National Institute for Health Research Health Technology Assessment Programme.
Journal Article
A randomised controlled trial of plasma exchange compared to standard of care in the treatment of severe COVID-19 infection (COVIPLEX)
2024
COVID-19 disease is associated with a hyperinflammatory, pro-thrombotic state and a high mortality. Our primary objective was to assess the change in inflammatory and thrombotic markers associated with PEX, and secondary objectives were to assess the effects of PEX on progression of respiratory failure and incidence of acute thrombotic events. We conducted a prospective, phase II, non-blinded randomised control trial of plasma exchange compared to standard of care in critically ill adults with severe COVID-19 associated respiratory failure, requiring supplemental oxygen or ventilatory support and elevated thrombo-inflammatory markers (LDH, CRP, ferritin, and D-Dimer). Patients randomised to receive PEX were treated with a daily single volume plasma exchange for a minimum of five days. Twenty-two patients were randomised of who 11 received PEX. Demographic and clinical characteristics were similar between groups at presentation. PEX was associated with a significant reduction in pro-thrombotic markers FVIII, VWF and VWF Ag: ADAMTS 13 ratio (
p
< 0.001). There were no differences in the reduction of inflammatory markers, severity of respiratory failure (
p
= 0.7), thrombotic events (
p
= 0.67), or mortality (
p
> 0.99) at 28 days. PEX successfully reduced pro-thrombotic markers, although was not associated with reduction in inflammatory markers, respiratory failure, or thrombotic events.
Trial registration
: (NCT04623255); first posted on 10/11/2020.
Journal Article
Screening for Depression in Medical Settings with the Patient Health Questionnaire (PHQ): A Diagnostic Meta-Analysis
by
Brealey, Stephen
,
Hewitt, Catherine
,
Richards, David
in
Algorithms
,
Biological and medical sciences
,
Clinical Review
2007
To summarize the psychometric properties of the PHQ2 and PHQ9 as screening instruments for depression.
We identified 17 validation studies conducted in primary care; medical outpatients; and specialist medical services (cardiology, gynecology, stroke, dermatology, head injury, and otolaryngology). Electronic databases from 1994 to February 2007 (MEDLINE, PsycLIT, EMBASE, CINAHL, Cochrane registers) plus study reference lists have been used for this study. Translations included US English, Dutch, Italian, Spanish, German and Arabic). Summary sensitivity, specificity, likelihood and diagnostic odds ratios (OR) against a gold standard (DSM-IV) Major Depressive Disorder (MDD) were calculated for each study. We used random effects bivariate meta-analysis at recommended cut points to produce summary receiver-operator characteristic (sROC) curves. We explored heterogeneity with metaregression.
Fourteen studies (5,026 participants) validated the PHQ9 against MDD: sensitivity = 0.80 (95% CI 0.71-0.87); specificity = 0.92 (95% CI 0.88-0.95); positive likelihood ratio = 10.12 (95% CI 6.52-15.67); negative likelihood ratio = 0.22 (0.15 to 0.32). There was substantial heterogeneity (Diagnostic Odds Ratio heterogeneity I2 = 82%), which was not explained by study setting (primary care versus general hospital); method of scoring (cutoff > or = 10 versus \"diagnostic algorithm\"); or study quality (blinded versus unblinded). The diagnostic validity of the PHQ2 was only validated in 3 studies and showed wide variability in sensitivity.
The PHQ9 is acceptable, and as good as longer clinician-administered instruments in a range of settings, countries, and populations. More research is needed to validate the PHQ2 to see if its diagnostic properties approach those of the PHQ9.
Journal Article