Timothy Rawson

Dr. Timothy Rawson

Faculty of Medicine, Department of Infectious Disease, Imperial College London, London, UK

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2020 in Clinical Microbiology and Infection
Verified
Journal Article
Closed access
NPNathan Peiffer-Smadja
Nathan Peiffer-Smadja
TRTimothy Rawson
Timothy Rawson
RAR. Ahmad
R. Ahmad
ABA. Buchard
A. Buchard
PGPantelis Georgiou
Pantelis Georgiou
AHA.H. Holmes
A.H. Holmes

20 May 2020 in Journal of Antimicrobial Chemotherapy
Verified
Journal Article
Open access
PDF file
TRTimothy Rawson
Timothy Rawson
LMLuke S. P. Moore
Luke S. P. Moore
ECEnrique Castro-Sánchez
Enrique Castro-Sánchez
ECEsmita Charani
Esmita Charani
FDFrances Davies
Frances Davies
AHAlison Holmes
Alison Holmes
The emergence of the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) has required an unprecedented response to control the spread of the infection and protect the most vulnerable within society. Whilst the pandemic has focused society on the threat of emerging infections and hand hygiene, certain infection control and antimicrobial stewardship policies may have to be relaxed. It is unclear whether the unintended consequences of these changes will have a net-positive or -negative impact on rates of antimicrobial resistance. Whilst the urgent focus must be on controlling this pandemic, sustained efforts to address the longer-term global threat of antimicrobial resistance should not be overlooked.

1 August 2017 in Clinical Microbiology and Infection
Verified
Journal Article
Open access
TRTimothy Rawson
Timothy Rawson
LMLuke S. P. Moore
Luke S. P. Moore
BHB. Hernandez
B. Hernandez
ECEsmita Charani
Esmita Charani
ECEnrique Castro-Sánchez
Enrique Castro-Sánchez
AHA.H. Holmes
A.H. Holmes
Clinical decision support systems (CDSS) for antimicrobial management can support clinicians to optimize antimicrobial therapy. We reviewed all original literature (qualitative and quantitative) to understand the current scope of CDSS for antimicrobial management and analyse existing methods used to evaluate and report such systems. PRISMA guidelines were followed. Medline, EMBASE, HMIC Health and Management and Global Health databases were searched from 1 January 1980 to 31 October 2015. All primary research studies describing CDSS for antimicrobial management in adults in primary or secondary care were included. For qualitative studies, thematic synthesis was performed. Quality was assessed using Integrated quality Criteria for the Review Of Multiple Study designs (ICROMS) criteria. CDSS reporting was assessed against a reporting framework for behaviour change intervention implementation. Fifty-eight original articles were included describing 38 independent CDSS. The majority of systems target antimicrobial prescribing (29/38;76%), are platforms integrated with electronic medical records (28/38;74%), and have a rules-based infrastructure providing decision support (29/38;76%). On evaluation against the intervention reporting framework, CDSS studies fail to report consideration of the non-expert, end-user workflow. They have narrow focus, such as antimicrobial selection, and use proxy outcome measures. Engagement with CDSS by clinicians was poor. Greater consideration of the factors that drive non-expert decision making must be considered when designing CDSS interventions. Future work must aim to expand CDSS beyond simply selecting appropriate antimicrobials with clear and systematic reporting frameworks for CDSS interventions developed to address current gaps identified in the reporting of evidence.

1 November 2019 in The Lancet Digital Health
Verified
Journal Article
Open access
TRTimothy Rawson
Timothy Rawson
SGSally A N Gowers
Sally A N Gowers
DFDavid M E Freeman
David M E Freeman
RWRichard C Wilson
Richard C Wilson
SSSanjiv Sharma
Sanjiv Sharma
AHAlison Holmes
Alison Holmes
Enhanced methods of drug monitoring are required to support the individualisation of antibiotic dosing. We report the first-in-human evaluation of real-time phenoxymethylpenicillin monitoring using a minimally invasive microneedle-based β-lactam biosensor in healthy volunteers. This first-in-human, proof-of-concept study was done at the National Institute of Health Research/Wellcome Trust Imperial Clinical Research Facility (Imperial College London, London, UK). The study was approved by London-Harrow Regional Ethics Committee. Volunteers were identified through emails sent to a healthy volunteer database from the Imperial College Clinical Research Facility. Volunteers, who had to be older than 18 years, were excluded if they had evidence of active infection, allergies to penicillin, were at high risk of skin infection, or presented with anaemia during screening. Participants wore a solid microneedle β-lactam biosensor for up to 6 h while being dosed at steady state with oral phenoxymethylpenicillin (five 500 mg doses every 6 h). On arrival at the study centre, two microneedle sensors were applied to the participant's forearm. Blood samples (via cannula, at -30, 0, 10, 20, 30, 45, 60, 90, 120, 150, 180, 210, 240 min) and extracellular fluid (ECF; via microdialysis, every 15 min) pharmacokinetic (PK) samples were taken during one dosing interval. Phenoxymethylpenicillin concentration data obtained from the microneedles were calibrated using locally estimated scatter plot smoothing and compared with free-blood and microdialysis (gold standard) data. Phenoxymethylpenicillin PK for each method was evaluated using non-compartmental analysis. Area under the concentration-time curve (AUC), maximum concentration, and time to maximum concentration were compared. Bias and limits of agreement were investigated with Bland-Altman plots. Microneedle biosensor limits of detection were estimated. The study was registered with ClinicalTrials.gov, number NCT03847610. Ten healthy volunteers participated in the study. Mean age was 42 years (SD 14). Seven (70%) were men. Microdialysis and microneedle results were similar for phenoxymethylpenicillin ECF maximum concentration (0·74 mg/L vs 0·64 mg/L; 95% CI -0·24 to 0·44; p=0·53), time to maximum concentration (1·18 h vs 1·10 h; -0·52 to 0·67; p=0·79), and AUC (1·54 mg × h/L vs 1·67 mg × h/L; -1·10 to 0·85; p=0·79). In total, 440 time points were compared with mean difference between measurements -0·16 mg/L (95% CI -1·30 to 0·82). Mean phenoxymethylpenicillin AUCs for free serum and microneedle PK were similar (1·77 mg × h/L [SD 0·59] vs 1·67 mg × h/L [1·00]; -0·77 to 0·97; p=0·81). Median coefficient of variation between sensors within individuals was 7% (IQR 4-17). Limit of detection for the microneedles was estimated at 0·17 mg/L. This study is proof-of-concept of real-time, microneedle sensing of penicillin in vivo. Future work will explore microneedle use in patient populations, their role in data generation to inform dosing recommendations, and their incorporation into closed-loop control systems for automated drug delivery. National Institute for Health Research Imperial Biomedical Research Centre, Mérieux Foundation.

15 July 2016 in World Journal of Emergency Surgery
Verified
Journal Article
Open access
PDF file
Massimo SartelliMassimo Sartelli
Massimo Sartelli
DWDieter G. Weber
Dieter G. Weber
ERETIENNE RUPPE
ETIENNE RUPPE
MBMatteo Bassetti
Matteo Bassetti
BWBrian J. Wright
Brian J. Wright
PVPerluigi Viale
Perluigi Viale
Intra-abdominal infections (IAI) are an important cause of morbidity and are frequently associated with poor prognosis, particularly in high-risk patients. The cornerstones in the management of complicated IAIs are timely effective source control with appropriate antimicrobial therapy. Empiric antimicrobial therapy is important in the management of intra-abdominal infections and must be broad enough to cover all likely organisms because inappropriate initial antimicrobial therapy is associated with poor patient outcomes and the development of bacterial resistance. The overuse of antimicrobials is widely accepted as a major driver of some emerging infections (such as C. difficile), the selection of resistant pathogens in individual patients, and for the continued development of antimicrobial resistance globally. The growing emergence of multi-drug resistant organisms and the limited development of new agents available to counteract them have caused an impending crisis with alarming implications, especially with regards to Gram-negative bacteria. An international task force from 79 different countries has joined this project by sharing a document on the rational use of antimicrobials for patients with IAIs. The project has been termed AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections). The authors hope that AGORA, involving many of the world's leading experts, can actively raise awareness in health workers and can improve prescribing behavior in treating IAIs.

5 April 2019 in ACS Sensors
Verified
Journal Article
Open access
SGSally A. N. Gowers
Sally A. N. Gowers
DFDavid M. E. Freeman
David M. E. Freeman
TRTimothy Rawson
Timothy Rawson
MRMichelle L. Rogers
Michelle L. Rogers
RWRichard C. Wilson
Richard C. Wilson
DODanny O’hAre
Danny O’hAre
Antimicrobial resistance poses a global threat to patient health. Improving the use and effectiveness of antimicrobials is critical in addressing this issue. This includes optimising the dose of antibiotic delivered to each individual. New sensing approaches that track antimicrobial concentration for each patient in real time could allow individualised drug dosing. This work presents a potentiometric microneedle-based biosensor to detect levels of β-lactam antibiotics in vivo in a healthy human volunteer. The biosensor is coated with a pH-sensitive iridium oxide layer, which detects changes in local pH as a result of β-lactam hydrolysis by β-lactamase immobilised on the electrode surface. Development and optimisation of the biosensor coatings are presented, giving a limit of detection of 6.8 µM in 10 mM PBS solution. Biosensors were found to be stable for up to two weeks at -20○C and to withstand sterilisation. Sensitivity was retained after application for 6 hours in vivo. Proof-of-concept results are presented showing that penicillin concentrations measured using the microneedle-based biosensor track those measured using both discrete blood and microdialysis sampling in vivo. These preliminary results show the potential of this microneedle-based biosensor to provide a minimally-invasive means to measure real-time β-lactam concentrations in vivo, representing an important first step towards a closed-loop therapeutic drug monitoring system.