Stephen O'Neill

Mr. Stephen O'Neill

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

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

Representative Publications

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18 October 2014 in Transplant International
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Journal Article
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SOStephen O'Neill
Stephen O'Neill
ARAmanda Roebuck
Amanda Roebuck
EKEmily Khoo
Emily Khoo
SWStephen J. Wigmore
Stephen J. Wigmore
EHEwen M. Harrison
Ewen M. Harrison
Donation after cardiac death (DCD) liver transplantation is increasingly common but concerns exist over the development of biliary complications and ischemic cholangiopathy (IC). This study aimed to compare outcomes between DCD and donation after brain death (DBD) liver grafts. Studies reporting on post-transplantation outcomes after Maastricht category III DCD liver transplantation were screened for inclusion. Odds ratios (OR) with 95% confidence intervals were produced using random-effects models for the incidence of biliary complications, IC, graft and recipient survival. Meta-regression was undertaken to identify between-study predictors of effect size for biliary complications and IC. PROSPERO Record: CRD42012002113. Twenty-five studies with 62 184 liver transplant recipients (DCD = 2478 and DBD = 59 706) were included. In comparison with DBD, there was a significant increase in biliary complications [OR = 2.4 (1.9, 3.1); P < 0.00001] and IC [OR = 10.5 (5.7, 19.5); P < 0.00001] following DCD liver transplantation. In comparison with DBD, at 1 year [OR = 0.7 (0.5, 0.8); P = 0.0002] and 3 years [OR = 0.6 (0.5, 0.8); P = 0.001], there was a significant decrease in graft survival following DCD liver transplantation. At 1 year, there was also a nonsignificant decrease [OR = 0.8 (0.6, 1.0); P = 0.08] and by 3 years a significant decrease [OR = 0.7 (0.5, 1.0); P = 0.04] found in recipient survival following DCD liver transplantation. Eleven factors were entered into meta-regression models, but none explained the variability in effect size between studies. DCD liver transplantation is associated with an increase in biliary complications, IC, graft loss and mortality. Significant unexplained differences in effect size exist between centers.

12 August 2013 in British Journal of Surgery
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Journal Article
Closed access
NVN T Ventham
N T Ventham
MHM Hughes
M Hughes
SOStephen O'Neill
Stephen O'Neill
NJN Johns
N Johns
RBR R Brady
R R Brady
Stephen J. WigmoreStephen J. Wigmore
Stephen J. Wigmore

23 May 2012 in BMJ
Verified
Journal Article
Open access
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EHEwen M Harrison
Ewen M Harrison
SOStephen O'Neill
Stephen O'Neill
TMThomas S Meurs
Thomas S Meurs
PWPang L Wong
Pang L Wong
MDMark Duxbury
Mark Duxbury
OGO James Garden
O James Garden
Objectives To define associations between hospital volume and outcomes following cholecystectomy, after adjustment for case mix using a national database. Design Retrospective, national population based study using multilevel modelling and simulation. Setting Locally validated administrative dataset covering all NHS hospitals in Scotland. Participants All patients undergoing cholecystectomy between 1 January 1998 and 31 December 2007. Main outcome measures Mortality, 30 day reoperation rate, 30 day readmission rate, and length of stay. Results We identified 59 918 patients who had a cholecystectomy in one of 37 hospitals: five hospitals had high volumes (>244 cholecystectomies/year), 10 had medium volumes (173-244), and 22 had low volumes (<173). Compared with low and medium volume hospitals, high volume hospitals performed more procedures non-electively (17.1% and 19.5% v 32.8%), completed more procedures laparoscopically (64.7% and 73.8% v 80.9%), and used more operative cholangiography (11.2% and 6.3% v 21.2%; χ2 test, all P<0.001). In a well performing multivariable analysis with bias correction for a low event rate, the odds ratio for death was greater in both the low volume (odds ratio 1.45, 95% confidence interval 1.06 to 2.00, P=0.022) and medium volume (1.52, 1.11 to 2.08, P=0.010) groups than in the high volume group. However, in simulation studies, absolute risk differences between volume groups were clinically negligible for patients with average risk (number needed to treat to harm, low v high volume, 3871, 1963 to 17 118), but were significant in patients with higher risk. In models accounting for the hierarchical structure of patients in hospitals, those in medium volume hospitals were more likely to undergo reoperation (odds ratio 1.74, 1.31 to 2.30, P<0.001) or be readmitted (1.17, 1.04 to 1.31, P=0.008) after cholecystectomy than those in high volume hospitals. Length of stay was shorter in high volume hospitals than in low (hazard ratio for discharge 0.78, 0.76 to 0.79, P<0.001) or medium volume hospitals (0.75, 0.74 to 0.77, P<0.001). These differences were also only of clinical significance in patients at higher risk. Conclusions There is wide variation among hospitals in the management of gallstone disease and an association between higher hospital volume and better outcome after a cholecystectomy. The relative risk of death is lower in high volume centres, and although absolute risk differences between volume groups are significant for elderly patients and patients with comorbidity, they are clinically negligible for those at average risk.

1 February 2014 in Diseases of the Colon & Rectum
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Journal Article
Closed access
NVNicholas T. Ventham
Nicholas T. Ventham
SOStephen O'Neill
Stephen O'Neill
NJNeil Johns
Neil Johns
RBRichard R. Brady
Richard R. Brady
KFKenneth C. H. Fearon
Kenneth C. H. Fearon
Novel local anesthetic blocks have become increasingly popular in the multimodal pain management following abdominal surgery, but have not been evaluated in a procedure-specific manner in colorectal surgery. This study aims to evaluate the efficacy of novel local anesthetic techniques in colorectal surgery. Electronic literature search of PubMed, EMBASE, and Cochrane databases (date range, January 1990 to February 2013) STUDY SELECTION: Randomized controlled trials comparing a novel local anesthetic technique with placebo/routine analgesia in adults undergoing open or laparoscopic colonic or rectal resection were selected. This is a meta-analysis of randomized controlled trials evaluating novel local anesthetic wound infiltration techniques such as wound catheter, transversus abdominis plane block, and intraperitoneal instillation in colorectal surgical procedures. The comparator group was defined as placebo/routine analgesia. The primary outcome was opiate requirement at 24 hours. Secondary outcomes included opiate requirements at 48 hours, pain numerical rating score at 24 and 48 hours at rest and on movement, recovery (length of stay, nausea and vomiting, time until bowel movement and diet resumption), and complications. Subgroup analysis was performed to evaluate specific local anesthetic techniques and open and laparoscopic surgery. Twelve randomized controlled trials compared local anesthetic techniques with placebo/routine analgesia. Local anesthetic techniques demonstrated a significant reduction in opiate requirement at 48 hours. Local anesthetic techniques were also associated with lower pain scores on movement at 24 and 48 hours, shorter length of stay, and earlier resumption of diet. The diverse study design led to statistical heterogeneity in several analyses. Novel local anesthetic wound infiltration techniques in colorectal surgery appear to reduce opiate requirements, to reduce pain scores, and to improve recovery in comparison with placebo/routine analgesia.

6 June 2014 in Nephron Experimental Nephrology
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Journal Article
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SOStephen O'Neill
Stephen O'Neill
EHEwen M. Harrison
Ewen M. Harrison
JRJames A. Ross
James A. Ross
SWStephen J. Wigmore
Stephen J. Wigmore
JHJeremy Hughes
Jeremy Hughes
The incidence of acute kidney injury due to ischaemia-reperfusion injury (IRI) is rising but effective treatments and preventative approaches are currently lacking. IRI is also an inevitable consequence of kidney transplantation and significantly contributes to delayed graft function. Heat-shock proteins (Hsps) are highly conserved and ubiquitously expressed molecular chaperones that help maintain and restore normal cellular function in the kidney following IRI. Hsp70 is one of the most frequently studied Hsps because of potential cytoprotective properties and attractiveness as a therapeutic target. However, the protective properties of Hsp70 in renal IRI are not fully understood and putative modes of protection include correction of protein conformation, cytoskeletal stabilisation, anti-inflammatory effects, requirement in autophagy, anti-apoptotic properties, influence over macrophage phenotype and stimulation of regulatory T cells. Significant clinical interest has been generated about the possibility of applying pharmacological agents to induce Hsp70 and prevent renal IRI, but prior to this, an increased mechanistic understanding of the protective nature of Hsp70 is needed. In particular, further investigation of Hsp expression on inflammatory cell behaviour is required as this could lead to the development of new therapeutic strategies for enhancing recovery following renal IRI and broaden the range of these therapies to a wider group of patients.

17 December 2018 in BJS Open
Verified
Journal Article
Open access
MLM. J. Lee
M. J. Lee
ASA. E. Sayers
A. E. Sayers
TDT. M. Drake
T. M. Drake
PMP. J. Marriott
P. J. Marriott
IAI. D. Anderson
I. D. Anderson
GBG van Boxel
G van Boxel
Small bowel obstruction is a common surgical emergency, and is associated with high levels of morbidity and mortality across the world. The literature provides little information on the conservatively managed group. The aim of this study was to describe the burden of small bowel obstruction in the UK. This prospective cohort study was conducted in 131 acute hospitals in the UK between January and April 2017, delivered by trainee research collaboratives. Adult patients with a diagnosis of mechanical small bowel obstruction were included. The primary outcome was in-hospital mortality. Secondary outcomes included complications, unplanned intensive care admission and readmission within 30 days of discharge. Practice measures, including use of radiological investigations, water soluble contrast, operative and nutritional interventions, were collected. Of 2341 patients identified, 693 (29·6 per cent) underwent immediate surgery (within 24 h of admission), 500 (21·4 per cent) had delayed surgery after initial conservative management, and 1148 (49·0 per cent) were managed non-operatively. The mortality rate was 6·6 per cent (6·4 per cent for non-operative management, 6·8 per cent for immediate surgery, 6·8 per cent for delayed surgery; P = 0·911). The major complication rate was 14·4 per cent overall, affecting 19·0 per cent in the immediate surgery, 23·6 per cent in the delayed surgery and 7·7 per cent in the non-operative management groups (P < 0·001). Cox regression found hernia or malignant aetiology and malnutrition to be associated with higher rates of death. Malignant aetiology, operative intervention, acute kidney injury and malnutrition were associated with increased risk of major complication. Small bowel obstruction represents a significant healthcare burden. Patient-level factors such as timing of surgery, acute kidney injury and nutritional status are factors that might be modified to improve outcomes.