ORCID Profile
0000-0003-0153-6651
Current Organisations
Flinders University
,
Townsville Hospital
,
Newcastle University
,
Royal Australasian College of Surgeons
,
Royal College of Surgeons of England
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Related Links
Publications
Contributors
Publisher: Oxford University Press
Date: 2010
A systematic review to evaluate the effectiveness of carnitine supplementation in improving walking performance among individuals with intermittent claudication
Publisher: Elsevier BV
Date: 07-2013
DOI: 10.1016/J.ATHEROSCLEROSIS.2013.03.004
Abstract: To evaluate the evidence for the use of carnitine supplementation in improving walking performance among in iduals with intermittent claudication. Systematic review. An electronic search of the literature was performed using MEDLINE (PubMed), Scopus, Cochrane Central Register of Controlled Trials and The Cochrane Library from inception through to November 2012. Search terms included peripheral arterial disease, intermittent claudication and carnitine. Reference lists of review articles and primary studies were also examined. Full reports of published experimental studies including randomized controlled trials and pre-test ost-test trials were selected for inclusion. A quality assessment was undertaken according to the Jadad scale. A total of 40 articles were retrieved, of which 23 did not meet the inclusion criteria. The 17 included articles reported on a total of 18 experimental studies of carnitine supplementation (5 pre-test ost-test 8 parallel RCT 5 cross-over RCT) for improving walking performance in adults with intermittent claudication. For pre-test ost-test studies, 300-2000 mg propionyl-L-carnitine (PLC) was administered orally or intravenously for a maximum of 90 days (7-42 participants) with statistically significant improvements of between 74 m and 157 m in pain free walking distance and between 71 m and 135 m in maximal walking distance across 3 out of 5 studies. Similarly, PLC (600 mg-3000 mg) was administered orally in 7 out of 8 parallel RCTs (22-485 participants), the longest duration being 12 months. All but one of the smallest trials demonstrated statistically significant improvements in walking performance between 31 and 54 m greater than placebo for pain free walking distance and between 9 and 86 m greater than placebo for maximal walking distance. A double-blind parallel RCT of cilostazol plus 2000 mg oral L-carnitine or placebo for 180 days (145 participants) did not demonstrate any significant improvement in walking performance. Of 5 cross-over RCTs (8-20 participants), 4 demonstrated significant improvements in walking performance following administration of 300-6000 mg L-carnitine or PLC. Compared to placebo, pain free walking distance and maximal walking distance improved by 23-132 m and 104 m respectively following carnitine intervention. Most trials demonstrated a small or modest improvement in walking performance with administration of PLC or L-carnitine. These findings were largely independent of level or quality of evidence, while there was some evidence that intravenous administration was more effective than oral administration and those with severe claudication may achieve greater benefits than those with moderate claudication. Routine carnitine supplementation in the form of PLC may therefore be a useful adjunct therapy for management of intermittent claudication. Further research is warranted to determine the optimal form, duration, dose and safety of carnitine supplementation across the spectrum of peripheral arterial disease severity and its effect with concurrent supervised exercise programs and best medical therapy. These studies should be supplemented with cost effectiveness studies to ensure that the return on the investment is acceptable.
Complex Regional Pain Syndrome: A Review
Publisher: Elsevier BV
Date: 03-2008
DOI: 10.1016/J.AVSG.2007.10.006
Abstract: Complex regional pain syndrome (CRPS), formerly known as "reflex sympathetic dystrophy," is a chronic neurological disorder characterized by disabling pain, swelling, vasomotor instability, sudomotor abnormality, and impairment of motor function. The disorder usually develops after minor trauma or surgery. No specific diagnostic test is available and, hence, diagnosis is based mainly on history, clinical examination, and supportive laboratory findings. This review gives a synopsis of CRPS and discusses the principles of management based on the limited available literature in the area. A literature search was conducted using electronic bibliographic databases (Medline, Embase, Pubmed, CENTRAL) from 1970 to 2006. Keywords complex regional pain syndrome, reflex sympathetic dystrophy, neuropathic pain, and causalgia were used for the search. Relevant articles from the reference lists in retrieved articles were also studied. There were 3,771 articles published in the area. Seventy-six randomized controlled trials were identified. Most studies were on the role of sympathetic blockade in the treatment of CRPS (n = 13). The role of sympathectomy is unclear, with some studies showing transient benefit and others showing no beneficial effects, with most studies containing only a small number of patients. Nine studies were on bisphosphonates or calcitonin. Studies involving bisphosphonates showed benefit, but studies involving calcitonin showed no definite benefit. Four studies were on cognitive behavioral therapy, physiotherapy, or occupational therapy, all of which demonstrated a potential beneficial effect. Three studies on spinal cord stimulation and two studies each on acupuncture, vitamin C, and steroid all showed a potential beneficial effect in pain reduction. The remaining studies were on miscellanous therapy or combination therapy, making it difficult to draw any conclusions on the effect of treatment. There is very little good evidence in the literature to guide treatment of CRPS. Early recognition and a multidisciplinary approach to management seems important in obtaining a good outcome. Treatments aimed at pain reduction and rehabilitation of limb function form the mainstay of therapy. Comorbidities, such as depression and anxiety, should be treated concurrently.
Carbon dioxide pneumoperitoneum causes severe peritoneal acidosis, unaltered by heating, humidification, or bicarbonate in a porcine model
Publisher: Springer Science and Business Media LLC
Date: 24-08-2004
DOI: 10.1007/S00464-003-9290-7
Abstract: Carbon dioxide (CO(2)) is the most common gas used for insufflation in laparoscopy, but its effects on peritoneal physiology are poorly understood. This study looks at the changes in peritoneal and bowel serosal pH during CO(2) pneumoperitoneum, and whether heating and humidification with or without bicarbonate alters the outcomes. Twenty-one pigs ided into four groups as follows: (1) standard (STD) laparoscopy (n = 5) (2) heated and humidified (HH) laparoscopy (n = 6) (3) heated and humidified with bicarbonate (HHBI) laparoscopy (n = 5) and (4) laparotomy (n = 5). Peritoneal pH, bowel serosal pH, and arterial blood gas (ABG) were obtained at 15-min intervals for 3 h. Severe peritoneal acidosis (pH range 6.59-6.74) was observed in all laparoscopy groups, and this was unaltered by heating and humidification or the addition of bicarbonate. Bowel serosal acidosis was observed in all laparoscopy groups with onset of pneumoperitoneum, but it recovered after 45 minutes. No significant changes in peritoneal or bowel serosal pH were observed in the laparotomy group. CO(2) pneumoperitoneum resulted in severe peritoneal acidosis that was unaltered by heating and humidification with or without bicarbonate. Alteration in peritoneal pH may conceivably be responsible for providing an environment favorable for tumor-cell implantation during laparoscopy.
Peritoneal pH during laparoscopy is dependent on ambient gas environment: helium and nitrous oxide do not cause peritoneal acidosis
Publisher: Springer Science and Business Media LLC
Date: 11-11-2004
DOI: 10.1007/S00464-003-9291-6
Abstract: Little is know about the effects of different insufflation gases on peritoneal pH during laparoscopy. However, these changes may influence the intracellular signalling system, resulting in altered cell growth or adhesiveness. The aim of this study was to determine the effects of carbon dioxide (CO(2)), nitrous oxide (N(2)O), and helium (He) on parietal and visceral peritoneal pH. The effect of different intraabdominal pressures on parietal and visceral peritoneal pH was also examined. We conducted both an ambient gas study and a pressure study. For the ambient gas study, 20 pigs were ided into the following four groups: (a) CO(2), (b) He, (c) N(2)O, and (d) abdominal wall lift (Lift) laparoscopy. Parietal and visceral peritoneal pH were measured at 15 min intervals for 180 min. For the pressure study, 15 pigs were ided into the following three groups: (a) CO(2), (b) He, (c) N(2)O laparoscopy. Baseline values were established for parietal and visceral peritoneal pH. Intraabdominal pressure was then increased stepwise at 1-mmHg intervals to 15 mmHg. After pressure was maintained for 15 min at each setting, parietal and visceral peritoneal pH were measured. Ambient gas environment was the major determinant of parietal peritoneal pH. Carbon dioxide caused parietal peritoneal acidosis. Helium, N(2)O, and Lift caused alkalotic parietal peritoneal pH. Intraabdominal pressure had a minor effect on parietal peritoneal pH. At higher intraabdominal pressure (12-15 vs 5-8 mmHg), CO(2) caused a slight decrease in parietal peritoneal pH, whereas N(2)O and He caused a slight increase in parietal peritoneal pH. Visceral peritoneal pH remained relatively unaffected during all studies. Parietal peritoneal pH during laparoscopy was highly dependent on the ambient gas environment. The effect of intraabdominal pressure on parietal peritoneal pH was of minor significance. Carbon dioxide caused a slight worsening of parietal peritoneal acidosis at higher intraabdominal pressure, whereas, N(2)O, He, and Lift did not cause parietal peritoneal acidosis.
Comparison of Angiographic Dissection Classification Systems in the Femoropopliteal Arteries Using IVUS Validation and Reliability Testing
Publisher: SAGE Publications
Date: 05-10-2022
DOI: 10.1177/15266028211047952
Abstract: Objective assessment of dissection severity is difficult. Recognition of this has led to the creation of classification systems. This study investigated the performance of the National Heart Lung and Blood Institute (NHLBI) and Kobayashi systems at differentiating severity of femoropopliteal dissection using intravascular ultrasound (IVUS) as the reference standard. Comparison between the 2 systems and the inter- and intra-observer reliability were also investigated. Angiographic and IVUS imaging was assessed in 51 cases sourced from a RCT investigating the use of IVUS in femoropopliteal disease. A total of 2 readers independently scored the angiography images according to NHLBI and Kobayashi dissection classification systems and a consensus score was obtained for each system in each case. The NHLBI classification was condensed into 3 grades of dissection to allow comparison between systems. Dissection length, dissection arc, minimum lumen area, and lumen area stenosis were obtained from the IVUS imaging. IVUS parameters were compared between grades of severity for both systems. Agreement in grading between the systems was assessed and IVUS parameters for each level of dissection severity were compared between systems. Inter and intra-observer agreement tested for each system. Dissection was present on IVUS in 92.2% (47/51) of cases and angiography identified 78.7% (37/47) of these. No difference was present in any IVUS parameters between mild and severe dissections with either classification system. No difference in IVUS findings was present for the same grades of dissection between systems. The 2 systems agreed on severity grade in 47 of 51 cases. The inter-observer agreement was for NHLBI was k=0.549 and k=0.627 for Kobayashi. Intra-observer agreement for NHLBI was k=0.633 and k=0.633 and for Kobayashi was k=0.657 and k=0.297. The lack of difference in IVUS parameters between mild and severe dissection for the NHLBI and Kobayashi systems raises doubts about their ability to effectively differentiate dissection severity. Weak to moderate reliability suggests that variability in interpreting dissection may be higher than acceptable. IVUS imaging is more sensitive for detecting dissection than angiography and research is required to establish the value of adding IVUS to dissection classification systems.
Anti-vimentin Antibody Detection in Recipients of Heart-Beating and Non–Heart Beating Donor Kidneys
Publisher: Elsevier BV
Date: 10-2005
DOI: 10.1016/J.TRANSPROCEED.2005.09.062
Abstract: Alternative donor sources include non-heart-beating donors (NHBDs). There donors have been exposed to significant ischemia, so that it is common to utilize machine perfusion to either improve the organs or at least assess their viability. Both prolonged warm ischemia and machine perfusion can potentially damage the vascular endothelium, thereby exposing vimentin to antigenic recognition. The aim of this study was to determine whether anti-vimentin antibodies could be detected in the blood of renal transplant recipients at specific time points after transplant and whether they could be related to the donor source. Fifty-one recipients of NHBD kidneys were compared to 52 recipients of heart-beating donor (HBD) kidneys. All recipients had similar anti-vimentin levels pretransplant. However, at 1 month those kidneys from Maastricht category II NHB donors showed significantly higher levels. At 6 months both Maastricht category II and category III NHB donor recipients displayed significantly higher levels than recipients of HBD kidneys.
Reconstruction of the aorto‐iliac segment in occlusive disease using the
AFX
unibody graft
Publisher: Wiley
Date: 23-08-2020
DOI: 10.1111/ANS.16236
Accuracy and Reliability of Peripheral Artery Calcium Scoring Systems Using an Intravascular Ultrasound Reference Standard
Publisher: Elsevier BV
Date: 04-2023
Endovascular treatment of diabetic foot ischemic ulcer – Technical review
Publisher: Elsevier BV
Date: 02-2020
Vascular Surgery
Publisher: Springer International Publishing
Date: 2017
Gastric outlet obstruction secondary to pancreatic cancer
Publisher: Springer Science and Business Media LLC
Date: 12-11-2001
DOI: 10.1007/S00464-001-9061-2
Abstract: Gastric outlet obstruction in patients with pancreatic cancer has a grim prognosis. Open surgical bypass is associated with high morbidity, whereas endoscopic duodenal stenting appears to provide better palliation. We reviewed the medical records of patients with gastric outlet obstruction secondary to pancreatic carcinoma who were admitted to our clinic between 1 October 1988, and 30 September 1998. The data included stage of disease, American Society of Anesthesiologists (ASA) class, surgical interventions, complications, and survival. A total of 250 patients with pancreatic cancer were identified. Twenty-five of them (10%) had gastric outlet obstruction. Of these 25, 17 were treated with gastrojejunostomy, six had duodenal stenting (Wallstent), and two were resectable. There was no significant difference between the gastrojejunostomy group and the duodenal stenting group in ASA class or stage of disease. For the gastrojejunostomy group, median survival was 64 days (range, 15-167) and postoperative stay in hospital was 15 days (range, 8-39). For the duodenal stenting group, median survival was 110.5 days (range, 42-212) and postoperative stay was 4 days (range, 2-6). Ten patients (58.8%) in the gastrojejunostomy group had delayed gastric emptying. All of the patients in the duodenal stenting group were able to tolerate a soft diet the day after stent placement. Thirty-day mortality in the gastrojejunostomy group was 17.64% in the duodenal stenting group, it was 0. In pancreatic carcinoma patients with gastric outlet obstruction, duodenal stenting results in an earlier discharge from hospital and possibly improved survival.
Diagnosis, Screening and Treatment of Abdominal, Thoracoabdominal and Thoracic Aortic Aneurysms
Publisher: InTech
Date: 12-09-2011
DOI: 10.5772/746
Dual ipsilateral renal transplantation from a non-heartbeating donor
Publisher: Royal College of Surgeons of England
Date: 05-2005
Abstract: A case is described where both kidneys from non-heart-beating (expanded criteria) donors were dual transplanted ipsilaterally. Although both kidneys passed viability tests on the Newcastle machine preservation system and biomarkers' evaluation, there were logistical issues where the cold ischaemic time was too protracted necessitating the transplantation of both kidneys into one recipient. The recipient had satisfactory outcome with the Cockcroft-Gault creatinine clearance of 72.47 (36.29 ml/min in idual kidney glomerular filtration rate) suggesting beneficial use of sub-optimal organs to improve outcome.
Audit of Diabetes in a Renal Transplant Population
Publisher: Elsevier BV
Date: 10-2005
DOI: 10.1016/J.TRANSPROCEED.2005.09.017
Abstract: To determine the prevalence of diabetes and its glycemic control in the renal transplant population of northeast England (Newcastle, Sunderland, Middlesborough, and Carlisle). All renal transplant notes in northeast England were reviewed. Data on patient details, type of diabetes, time of onset of diabetes, diabetes medications, time of insulin commencement, date of renal transplant, immunosuppressive medications, and HbA(1C) were recorded. Living renal transplant patients (n = 1073) transplanted between March 1982 and November 5, 2003 were identified. One hundred and nine (10.2%) patients had diabetes, of whom 39 were type 1 and 70 were type 2. Median HBA(1C) in patients with type 1 diabetes on tacrolimus was 10.1% +/- 1.94% (SD) versus 7.8% +/- 1.98% (SD) for patients not on tacrolimus. Among patients with type 2 diabetes, 25 had diabetes prior to transplant and 45 (4.5%) developed posttransplant diabetes (PTDM). Those who developed PTDM and were taking tacrolimus were more likely to require insulin for blood glucose control (0.39 U/kg/24 hours vs 0 U/kg/24 hours P = .05) compared to those not on tacrolimus. Both type 1 and type 2 diabetics on tacrolimus showed better preservation of renal function as measured by mean serum creatinine (type 1: 145 +/- 53 vs 196 +/- 74, P = .02 type 2 pretransplant: 159 +/- 73 vs 172 +/- 59, P = .35 type 2 posttransplant: 123 +/- 35 vs 167 +/- 63, P = .01). Tacrolimus use in renal transplant patients with diabetes appeared to be associated with more problematic blood glucose control however, it seemed to be better at preserving renal function. Intensive blood glucose monitoring is recommended for this group.
Related Organisations
Newcastle University
Location: United Kingdom of Great Britain and Northern Ireland
Royal College Of Surgeons Of England
Location: United Kingdom of Great Britain and Northern Ireland
Related Funding Activities
No related grants have been discovered for Yew Toh Wong.