BACKGROUND: Although the effect of synbiotic therapy using prebiotics and probiotics has been rep... more BACKGROUND: Although the effect of synbiotic therapy using prebiotics and probiotics has been reported in hepatobiliary surgery, there are no reports of the effect on elective living-donor liver transplantation (LDLT).
ASAIO journal (American Society for Artificial Internal Organs : 1992)
Cardiopulmonary bypass causes a systemic inflammatory reaction. Activation of leukocytes is an im... more Cardiopulmonary bypass causes a systemic inflammatory reaction. Activation of leukocytes is an important part of this process, and is known to directly contribute to the development of postoperative coagulopathy, and thus hemorrhage. The removal of leukocytes from the cardiopulmonary bypass circulation, using specialized filters, has been proposed as one method for attenuating this inflammatory response. However, there is no consensus on its effectiveness. We used meta-analytical techniques to systematically assess the literature reporting on the potential effect of systemic leukofiltration on perioperative hemorrhage. Random effects modeling was used to calculate overall estimate, and heterogeneity was assessed. Systemic leukofiltration made no significant impact on chest tube drainage in the first 24 hours (weighted mean difference [WMD], x23.9 ml; 95% confidence interval [CI], x95.48-47.61; p = 0.51) or on the total packed red cell transfusion requirements of each patient (WMD, 7...
... Alison Walker, BSc(Hons), MbChB, MRCPCH, Mark Davidson, MBChB, Mrcpch, BSc(Med Sci), Elizabet... more ... Alison Walker, BSc(Hons), MbChB, MRCPCH, Mark Davidson, MBChB, Mrcpch, BSc(Med Sci), Elizabeth Chalmers, MChB, MD, MRCP, FRCPath, Royal ... Accessed March 18, 2010 3. Spenceley N, Krahn G, Skippen PW, et al: Evaluation of a pediatric central venous oxim-etry ...
Delayed surgical reconstruction of craniofacial bony defects can lead to secondary intention heal... more Delayed surgical reconstruction of craniofacial bony defects can lead to secondary intention healing, defect volume loss and soft-tissue fibrotic contracture, giving poorer aesthetic and functional results. Utilising temporary porous space maintainers, made by leaching porogens (pore inducers) from curable matrices e.g. Poly (methylmethacrylate) (PMMA) cement, limits aforementioned complications. Carboxymethylcellulose (CMC) is a demonstrated, efficacious porogen but is unlicensed for interstitial use. Pre-existing licensed products may provide alternatives (e.g. gelatin-based products), facilitating clinical application. This project aims to investigate PMMA incorporating a gelatin-based porogen and compare scaffold characteristics, e.g. interconnectivity, porosity and porogen release, to PMMA-CMC. PMMA-gelatin scaffolds of different weight percentages and yields (water/ unit of gelatin) were mould polymerised then lyophilised. Microcomputed tomography analysis of scaffold porosity and interconnectivity was performed pre/post gelatin leaching and gelatin release was measured by microBSA protein assay. PMMA-gelatin demonstrated lower porosity and pore interconnectivity than PMMA-CMC of identical weight incorporation. Increasing yield and/ or weight incorporation increased porosity. Leaching was slow (mg/ml/ hr), with the majority of porogen still entrapped at three weeks dissolution.
Aims: Diagnosis of acute appendicitis has been based traditionally on history and examination fin... more Aims: Diagnosis of acute appendicitis has been based traditionally on history and examination findings, with leukocyte count (WCC) used as an adjunct. C-reactive protein (CRP) is now also measured routinely. We aimed to identify whether CRP improves diagnostic accuracy in suspected acute appendicitis. Methods: 16-month retrospective study of 256 consecutive adult patients undergoing appendicectomy for suspected appendicitis. CRP and WCC on presentation were compared with post-operative histological diagnosis of acute appendicitis. Results: 68% (174) of patients undergoing appendicectomy had a histological diagnosis of acute appendicitis. Used in isolation WCC >14 yielded: sensitivity ¼0.43; specificity ¼0.88; PPV ¼0.88. Used in isolation CRP >20 yielded: sensitivity ¼0.56; specificity ¼0.67; PPV ¼0.78. Only when CRP >100 does specificity increase to >0.8. Combined WCC >14 and CRP >20 (sensitivity ¼0.22; specificity ¼0.9; PPV ¼0.83) did not improve PPV compared with WCC alone and only marginally improved specificity. Conclusions: When used alone WCC is more useful in predicting acute appendicitis at appendicectomy than CRP. Combining both markers has no impact on the likelihood of a correct diagnosis when compared with using a WCC >14 alone. Measuring CRP levels in suspected acute appendicitis does not improve diagnostic accuracy and therefore cannot be financially or clinically justified.
... Trainees and junior faculty will also benefit from a number of how to chapters focused on d... more ... Trainees and junior faculty will also benefit from a number of how to chapters focused on data presentation, critical reading, writing papers, and submitting grants. ... Timothy M. Pawlik, MD, MPH,. Steven Leach MD. Johns Hopkins University. ...
... Research: Concepts and Methodology Mohammed Shamim Rahman, Sana Usman, Oliver Warren, and Tha... more ... Research: Concepts and Methodology Mohammed Shamim Rahman, Sana Usman, Oliver Warren, and Thanos Athanasiou 36 ... Disproportionate sampling does not follow equal weighting and allows over sam-pling of a small but important stratum. ...
Training in surgical disciplines in the United Kingdom has undergone tremendous change over the p... more Training in surgical disciplines in the United Kingdom has undergone tremendous change over the past two decades. The introduction of specialist training programmes, working time directives, quality ratings and a drive toward ambulatory and minimal access surgery have led to challenges with respect to training and service commitments of healthcare professionals. A structured and centralised training system was introduced, with the concept of core followed by specialty-specific progression, in an openly competitive manner. Within this system is the need to commence training on simulation models, and to demonstrate proficiency prior to performance of tasks on patients. This should be underpinned by objective measures such as video or dexterity-based tools. There is also a clear need to provide personal, professional and leadership development in the form of mentorship and appraisal systems. Though continuing to develop, the profession must be mindful of current and future advances to ensure the delivery of surgeons for the future who aspire toward excellence.
BACKGROUND: Although the effect of synbiotic therapy using prebiotics and probiotics has been rep... more BACKGROUND: Although the effect of synbiotic therapy using prebiotics and probiotics has been reported in hepatobiliary surgery, there are no reports of the effect on elective living-donor liver transplantation (LDLT).
ASAIO journal (American Society for Artificial Internal Organs : 1992)
Cardiopulmonary bypass causes a systemic inflammatory reaction. Activation of leukocytes is an im... more Cardiopulmonary bypass causes a systemic inflammatory reaction. Activation of leukocytes is an important part of this process, and is known to directly contribute to the development of postoperative coagulopathy, and thus hemorrhage. The removal of leukocytes from the cardiopulmonary bypass circulation, using specialized filters, has been proposed as one method for attenuating this inflammatory response. However, there is no consensus on its effectiveness. We used meta-analytical techniques to systematically assess the literature reporting on the potential effect of systemic leukofiltration on perioperative hemorrhage. Random effects modeling was used to calculate overall estimate, and heterogeneity was assessed. Systemic leukofiltration made no significant impact on chest tube drainage in the first 24 hours (weighted mean difference [WMD], x23.9 ml; 95% confidence interval [CI], x95.48-47.61; p = 0.51) or on the total packed red cell transfusion requirements of each patient (WMD, 7...
... Alison Walker, BSc(Hons), MbChB, MRCPCH, Mark Davidson, MBChB, Mrcpch, BSc(Med Sci), Elizabet... more ... Alison Walker, BSc(Hons), MbChB, MRCPCH, Mark Davidson, MBChB, Mrcpch, BSc(Med Sci), Elizabeth Chalmers, MChB, MD, MRCP, FRCPath, Royal ... Accessed March 18, 2010 3. Spenceley N, Krahn G, Skippen PW, et al: Evaluation of a pediatric central venous oxim-etry ...
Delayed surgical reconstruction of craniofacial bony defects can lead to secondary intention heal... more Delayed surgical reconstruction of craniofacial bony defects can lead to secondary intention healing, defect volume loss and soft-tissue fibrotic contracture, giving poorer aesthetic and functional results. Utilising temporary porous space maintainers, made by leaching porogens (pore inducers) from curable matrices e.g. Poly (methylmethacrylate) (PMMA) cement, limits aforementioned complications. Carboxymethylcellulose (CMC) is a demonstrated, efficacious porogen but is unlicensed for interstitial use. Pre-existing licensed products may provide alternatives (e.g. gelatin-based products), facilitating clinical application. This project aims to investigate PMMA incorporating a gelatin-based porogen and compare scaffold characteristics, e.g. interconnectivity, porosity and porogen release, to PMMA-CMC. PMMA-gelatin scaffolds of different weight percentages and yields (water/ unit of gelatin) were mould polymerised then lyophilised. Microcomputed tomography analysis of scaffold porosity and interconnectivity was performed pre/post gelatin leaching and gelatin release was measured by microBSA protein assay. PMMA-gelatin demonstrated lower porosity and pore interconnectivity than PMMA-CMC of identical weight incorporation. Increasing yield and/ or weight incorporation increased porosity. Leaching was slow (mg/ml/ hr), with the majority of porogen still entrapped at three weeks dissolution.
Aims: Diagnosis of acute appendicitis has been based traditionally on history and examination fin... more Aims: Diagnosis of acute appendicitis has been based traditionally on history and examination findings, with leukocyte count (WCC) used as an adjunct. C-reactive protein (CRP) is now also measured routinely. We aimed to identify whether CRP improves diagnostic accuracy in suspected acute appendicitis. Methods: 16-month retrospective study of 256 consecutive adult patients undergoing appendicectomy for suspected appendicitis. CRP and WCC on presentation were compared with post-operative histological diagnosis of acute appendicitis. Results: 68% (174) of patients undergoing appendicectomy had a histological diagnosis of acute appendicitis. Used in isolation WCC >14 yielded: sensitivity ¼0.43; specificity ¼0.88; PPV ¼0.88. Used in isolation CRP >20 yielded: sensitivity ¼0.56; specificity ¼0.67; PPV ¼0.78. Only when CRP >100 does specificity increase to >0.8. Combined WCC >14 and CRP >20 (sensitivity ¼0.22; specificity ¼0.9; PPV ¼0.83) did not improve PPV compared with WCC alone and only marginally improved specificity. Conclusions: When used alone WCC is more useful in predicting acute appendicitis at appendicectomy than CRP. Combining both markers has no impact on the likelihood of a correct diagnosis when compared with using a WCC >14 alone. Measuring CRP levels in suspected acute appendicitis does not improve diagnostic accuracy and therefore cannot be financially or clinically justified.
... Trainees and junior faculty will also benefit from a number of how to chapters focused on d... more ... Trainees and junior faculty will also benefit from a number of how to chapters focused on data presentation, critical reading, writing papers, and submitting grants. ... Timothy M. Pawlik, MD, MPH,. Steven Leach MD. Johns Hopkins University. ...
... Research: Concepts and Methodology Mohammed Shamim Rahman, Sana Usman, Oliver Warren, and Tha... more ... Research: Concepts and Methodology Mohammed Shamim Rahman, Sana Usman, Oliver Warren, and Thanos Athanasiou 36 ... Disproportionate sampling does not follow equal weighting and allows over sam-pling of a small but important stratum. ...
Training in surgical disciplines in the United Kingdom has undergone tremendous change over the p... more Training in surgical disciplines in the United Kingdom has undergone tremendous change over the past two decades. The introduction of specialist training programmes, working time directives, quality ratings and a drive toward ambulatory and minimal access surgery have led to challenges with respect to training and service commitments of healthcare professionals. A structured and centralised training system was introduced, with the concept of core followed by specialty-specific progression, in an openly competitive manner. Within this system is the need to commence training on simulation models, and to demonstrate proficiency prior to performance of tasks on patients. This should be underpinned by objective measures such as video or dexterity-based tools. There is also a clear need to provide personal, professional and leadership development in the form of mentorship and appraisal systems. Though continuing to develop, the profession must be mindful of current and future advances to ensure the delivery of surgeons for the future who aspire toward excellence.
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