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1.
Ann R Coll Surg Engl ; 106(3): 213-218, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37218655

RESUMO

INTRODUCTION: Colorectal liver metastases (CRLM) are associated with a high recurrence rate after surgery. There is paucity of high-quality evidence regarding the nature and overall benefit of surveillance after hepatectomy for CRLM. As part of a broader programme of research, this study aimed to assess current strategies for surveillance after liver resection for CRLM and outline surgeons' opinions regarding the benefit of postoperative surveillance. METHODS: An online survey was sent to clinicians performing surgery for CRLM at tertiary hepatobiliary centres in the UK. RESULTS: There were responses from a total of 23 centres (88% response rate); 15/23 centres used standardised surveillance protocols for all patients. Most centres followed patients up at six months, but there is variation in postoperative surveillance at 3, 9, 18 and beyond 60 months. Patient comorbidities, indeterminate findings on imaging, margin status and assessment of recurrence risk were identified as the major factors influencing personalised surveillance strategies. There was clear clinician equipoise regarding the costs and benefits of surveillance. CONCLUSION: There is heterogeneity in postoperative follow-up for CRLM in the UK. High-quality prospective studies and randomised trials are necessary to elucidate the value of postoperative surveillance and identify optimal follow-up strategies.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Estudos Transversais , Estudos Prospectivos , Hepatectomia , Neoplasias Hepáticas/cirurgia , Neoplasias Colorretais/cirurgia
2.
Hernia ; 26(3): 751-759, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34718903

RESUMO

BACKGROUND: Abdominal wall hernia repair is one of the most commonly performed surgical procedures worldwide, yet despite this, there remains a lack of high-quality evidence to support best management. The aim of the study was to use a modified Delphi process to determine future research priorities in this field. METHODS: Stakeholders were invited by email, using British Hernia Society membership details or Twitter, to submit individual research questions via an online survey. In addition, questions obtained from a patient focus group (PFG) were collated to form Phase I. Two rounds of prioritization by stakeholders (phases II and III) were then completed to determine a final list of research questions. All questions were analyzed on an anonymized basis. RESULTS: A total of 266 questions, 19 from the PFG, were submitted by 113 stakeholders in Phase I. Of these, 64 questions were taken forward for prioritization in Phase II, which was completed by 107 stakeholders. Following Phase II analysis, 97 stakeholders prioritized 36 questions in Phase III. This resulted in a final list of 14 research questions, 3 of which were from the PFG. Stakeholders included patients and healthcare professionals (consultant surgeons, trainee surgeons and other multidisciplinary members) from over 27 countries during the 3 phases. CONCLUSION: The study has identified 14 key research priorities pertaining to abdominal wall hernia surgery. Uniquely, these priorities have been determined from participation by both healthcare professionals and patients. These priorities should now be addressed by well-designed, high-quality international collaborative research.


Assuntos
Pesquisa Biomédica , Procedimentos Cirúrgicos do Sistema Digestório , Hérnia Abdominal , Técnica Delphi , Herniorrafia , Humanos
4.
Ann Med Surg (Lond) ; 57: 228-235, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32802324

RESUMO

BACKGROUND: Closure of the appendiceal stump is a key step performed during laparoscopic appendicectomy. Inadequate management of the appendiceal stump has the potential to cause significant morbidity. Several methods of stump closure have been described, however high-level evidence is limited. We performed a systematic review evaluating clinical outcomes and quality of the evidence for the methods of appendiceal stump closure. METHODS: A systematic literature search was performed using Medline, Embase, Cochrane Database and Google Scholar to identify studies comparing appendiceal stump closure methods in laparoscopic appendectomy for acute appendicitis from inception to October 2019. Data regarding operative duration, peri-operative complications, length of stay and costs were collated from all included studies. RESULTS: From 160 identified studies, 19 met the inclusion criteria. Endoloops and endoclips provide equivalent clinical outcomes at lower cost, while operative duration was shortest with endoclip closure. Endostapler devices have the lowest rate of peri-operative complications (3.56%), however their cost limits their regular use in many healthcare environments. Post-operative complication rate and length of stay were similar for all stump closure methods. Conclusion: Although there are no significant differences in method of stump closure in laparoscopic appendectomy, closure with endoclips provides the shortest operative duration. There is a need for robust and standardized reporting of cost data when comparing stump closure methods, together with higher level evidence in the form of multi-centre randomized controlled trials before firm conclusions can be drawn regarding the optimal method of stump closure.

5.
Tech Coloproctol ; 23(11): 1065-1072, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31720908

RESUMO

BACKGROUND: Rectal prolapse is a disease presentation with a prevalence of about 1%, mainly affecting older women. It usually presents with symptoms of rectal mass, rectal bleeding, fecal incontinence or constipation, with patients frequently feeling socially isolated as a result. Perineal rectosigmoidectomy is associated with lesser morbidity and mortality than the abdominal procedure, but with a much higher recurrence rate. Therefore, this technique is mainly suitable for the frail elderly patient. Specific outcomes in an elderly population have been described in only a few studies. We evaluated the morbidity, mortality, recurrence rate and functional results after this procedure related to age. METHODS: All patients who underwent a perineal rectosigmoidectomy over a 10-year period in two tertiary referral centers were included in the study. American Society of Anesthesiology (ASA) grade, pre- and postoperative symptoms, pathology-reported post-fixation specimen length, length of in-patient stay, 30-day morbidity/mortality, and recurrence were measured. RESULTS: A total of 45 patients underwent a perineal rectosigmoidectomy. Forty-three (95%) were female, with a median age of 82.0 years (IQR 70.5-86.5), ASA grade III and median follow-up of 20 months (range 8.5-45.5 months). Half of the cohort was over 80 years old. Significant symptomatic relief was achieved, predominantly the resolution of rectal mass (8.9% vs. 60.0% preoperatively), fecal incontinence (15.6% vs. 46.7%) and constipation (4.4% vs. 26.7%). The median length of stay was 6 days, while morbidity occurred in 14 patients (31.1%) and recurrence occurred in 6 patients (13%). There were no deaths within 30 days of the procedure and outcomes were comparable in the < 80 and ≥ 80 age group. CONCLUSIONS: Perineal rectosigmoidectomy is safe for older patients with greater comorbidities resulting in good functional results and is associated with low morbidity and mortality.


Assuntos
Colo Sigmoide/cirurgia , Protectomia/efeitos adversos , Protectomia/métodos , Prolapso Retal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Constipação Intestinal/etiologia , Incontinência Fecal/etiologia , Feminino , Idoso Fragilizado , Nível de Saúde , Humanos , Tempo de Internação , Masculino , Períneo , Prolapso Retal/complicações , Recidiva , Avaliação de Sintomas , Centros de Atenção Terciária , Resultado do Tratamento , Reino Unido
6.
Colorectal Dis ; 21(7): 775-781, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30848537

RESUMO

AIM: Studies addressing the benefit of early intervention are prone to lead-time bias, which results in an artificial improvement in cancer-specific mortality. We have previously compared the age at death for patients with colorectal cancer presenting on an emergency or elective basis. In this study, we aimed to repeat the analysis with a minimum follow-up of 10 years. METHOD: A nonscreen-detected cohort of patients presenting with colorectal cancer to three Lanarkshire Hospitals between 2000 and 2006 were entered into a prospective database, with analysis performed on 28 November 2016. The following data were collected: age at death, presentation type (emergency/elective), operative intent (palliative/curative) and Dukes stage. Results are presented as [mean (95% confidence intervals)]. Statistical analysis was undertaken using Student's t-test and multivariate analysis performed using Cox proportional hazard models. RESULTS: One thousand six hundred and thirty-six patients were identified. Elective patients presented younger than emergency patients [67.9 (67.3-68.5) vs 70.9 (69.6-72.2) years; P < 0.0001]. Overall mortality was 71.1% at time of analysis; no difference was seen in the mean age at death between emergency and elective presentation [73.5 (72.4-74.8) vs 73.6 (72.3-74.9) years; P = 0.841]. CONCLUSION: Current early detection strategies to diagnose colorectal cancer may improve cancer-specific survival by increasing lead-time bias. However, in our cohort of symptomatic patients, treatment on an elective or emergency basis does not influence overall survival. These data suggest that in selected patients, particularly where there is comorbidity, it may be reasonable to adopt a more expectant approach to investigate and treat colorectal symptoms.


Assuntos
Fatores Etários , Neoplasias Colorretais/mortalidade , Procedimentos Cirúrgicos Eletivos/mortalidade , Tratamento de Emergência/mortalidade , Fatores de Tempo , Idoso , Viés , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Prospectivos
7.
Br J Surg ; 106(2): e62-e72, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30620075

RESUMO

BACKGROUND: Technological advances have led to the generation of large amounts of data, both in surgical research and practice. Despite this, it is unclear how much originates in low- and middle-income countries (LMICs) and what barriers exist to the use of such data in improving surgical care. The aim of this review was to capture the extent and impact of programmes that use large volumes of patient data on surgical care in LMICs. METHODS: A PRISMA-compliant systematic literature review of PubMed, Embase and Google Scholar was performed in August 2018. Prospective studies collecting large volumes of patient-level data within LMIC settings were included and evaluated qualitatively. RESULTS: A total of 68 studies were included from 71 LMICs, involving 708 032 patients. The number of patients in included studies varied widely (from 335 to 428 346), with 25 reporting data on 3000 or more LMIC patients. Patient inclusion in large-data studies in LMICs has increased dramatically since 2015. Studies predominantly involved Brazil, China, India and Thailand, with low patient numbers from Africa and Latin America. Outcomes after surgery were commonly the focus (33 studies); very few large studies looked at access to surgical care or patient expenditure. The use of large data sets specifically to improve surgical outcomes in LMICs is currently limited. CONCLUSION: Large volumes of data are becoming more common and provide a strong foundation for continuing investigation. Future studies should address questions more specific to surgery.


Assuntos
Big Data , Cirurgia Geral/normas , Melhoria de Qualidade/estatística & dados numéricos , Países em Desenvolvimento , Cirurgia Geral/estatística & dados numéricos , Humanos , Avaliação de Resultados em Cuidados de Saúde
8.
Ann R Coll Surg Engl ; 100(6): 454-458, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29543058

RESUMO

Introduction The use of polymeric clips in securing the appendiceal stump has been increasingly reported as a viable alternative to current methods in emergency laparoscopic appendicectomy. We evaluated the operative outcomes following the use of polymeric clips versus endoscopic ligatures. The primary endpoint was operative time, with secondary outcomes including complications, inpatient stay, and cost analysis. Materials and methods Operative records were retrospectively analysed to identify patients undergoing laparoscopic appendicectomy between January 2014 and June 2015. Data collected included age, gender, body mass index, duration of surgery, length of hospital stay, antibiotic use, preoperative haematological and biochemical parameters, 30-day readmission rate and complications. Results A total of 125 patients were included within the study, with 78 within the endoloop group and 47 in the polymeric clip group. There were no differences in age, gender, body mass index, hospital stay, antibiotic use, 30-day readmission rates or postoperative complications. Operative time was significantly reduced in the polymeric clip group (59 vs. 68 minutes, P = 0.00751). The use of polymeric clips cost £21 compared with £49 for endoloops per operation, which rose to £70 if both clips and endoloops were used during the procedure. Discussion Polymeric clips are a safe, viable and economical method for securing the appendiceal stump during laparoscopic appendicectomy. The clinical significance of nine minutes of reduced operating time in the polymeric clip cohort warrants further study with an adequately powered randomised controlled trial.


Assuntos
Apendicectomia/instrumentação , Apendicite/cirurgia , Laparoscopia/instrumentação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apendicectomia/economia , Apendicectomia/métodos , Apendicite/economia , Criança , Feminino , Custos Hospitalares/estatística & dados numéricos , Humanos , Laparoscopia/economia , Laparoscopia/métodos , Tempo de Internação/economia , Tempo de Internação/estatística & dados numéricos , Ligadura , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Int J Surg ; 51: 199-204, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29407251

RESUMO

AIMS: Intravenous (IV) fluid administration continues to be a mainstay of care in General Surgery. Yet if they are prescribed incorrectly significant morbidity including electrolyte abnormalities, renal impairment and cardiac failure can develop. Despite this, it is frequently the responsibility of the most junior staff to prescribe IV fluids. We aim to analyse the understanding of IV fluid prescribing amongst junior doctors and to describe variability in clinical practice. METHODS: We undertook a multicentre questionnaire study. Foundation doctors and specialty trainees were invited to undertake a two part paper-based questionnaire. Part one analysed baseline knowledge of the concentration of commonly prescribed fluids. Part two consisted of four clinical vignettes requiring a IV fluid prescribing decision by the surveyed doctor. RESULTS: A total of 143 Doctors working in 8 hospitals were recruited. 65 (45.5%) doctors correctly stated the daily maintenance fluid requirements of water for an adult (25-30 mls/kg/day), while only 54 (37.8%) knew the sodium concentration of 0.9% NaCl. Lack of postgraduate experience (p = 0.011), qualifying from a medical school outside the United Kingdom (p < 0.0001) and working in one of the eight hospitals in this study (p < 0.0001) were associated with a lower knowledge level. There was limited consensus in prescribing in the responses to the 4 clinical scenarios, with 69 unique combinations of fluid choice, rate and volume prescribed. CONCLUSIONS: Knowledge of the constituents of common IV fluids and routine requirement for fluid and common electrolytes is poor across junior doctors of all grades, driving large variation in clinical practice.


Assuntos
Hidratação/métodos , Adulto , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Infusões Intravenosas , Médicos , Prescrições , Inquéritos e Questionários
10.
BJS Open ; 1(4): 97-105, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29951611

RESUMO

BACKGROUND: Clinical practice guidelines (CPGs) are widely used to inform the development of protocols for clinical management. Previous work has demonstrated that the quality of CPGs varies widely. This systematic review aimed to determine the quality of CPGs in kidney transplantation in the UK. METHODS: CPGs in kidney transplantation published between 2010 and 2017 were identified through searches of MEDLINE, NHS NICE Evidence, and websites of relevant UK societies. Using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool, three appraisers rated the quality of CPGs across six domains, the overall quality of each CPG, and whether it should be recommended for future use. Domain scores were calculated, and inter-rater reliability using the intraclass correlation coefficient (ICC) was reported. RESULTS: Thirteen CPGs met the inclusion criteria. The domain 'clarity of presentation' scored highest, followed closely by 'scope and purpose'. The poorest scoring domains were 'applicability' and 'editorial independence'. Editorial independence also had the widest range of scores. Of the 13 CPGs, one was not recommended for future use, seven were recommended for use with modifications, and five for future use with no need for modification. Mean overall CPG quality was 5 (range 3-6) of a maximum score of 7, and mean inter-rater reliability was substantial with an ICC of 0·71. CONCLUSION: UK CPGs scored satisfactorily, although with wide variation in how well each domain scored both within and across CPGs. The quality of UK CPGs can still be improved.

12.
Am J Transplant ; 14(12): 2765-76, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25395336

RESUMO

Invasive fungal infections (IFIs) cause significant morbidity and mortality in liver transplant recipients, but the need and best agent for prophylaxis is uncertain. A comprehensive literature search was performed to identify randomized controlled trials comparing regimens for antifungal prophylaxis in liver transplant recipients. Direct comparisons were made between treatments using random-effects meta-analysis and a Bayesian network meta-analysis was performed for the primary end point of proven IFI. Fourteen studies met inclusion criteria, reporting comparisons of fluconazole, liposomal amphotericin B (L-AmB), itraconazole, micafungin and placebo. Overall, antifungal prophylaxis reduced the rate of proven IFI (odds ratio [OR] 0.37, confidence interval [CI] 0.19-0.72, p = 0.003), suspected or proven IFI (OR 0.40, CI 0.25-0.66, p = 0.0003) and mortality due to IFI (OR 0.32, CI 0.10-0.83, p = 0.02) when compared to placebo. All-cause mortality was not significantly affected. There was no difference in risk of adverse events requiring cessation of prophylaxis (OR 1.11, 95% CI 0.48-2.55, p = 0.81). In the network meta-analysis an equivalent reduction in the rate of IFI was seen with fluconazole (OR 0.21, CI 0.06-0.57) and L-AmB (OR 0.21, CI 0.05-0.71) compared with placebo. Routine prophylaxis with fluconazole or L-AmB reduces the incidence of IFI following liver transplantation, and the available evidence suggests that the two are equivalent in efficacy.


Assuntos
Antibioticoprofilaxia , Antifúngicos/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Hepatopatias/cirurgia , Transplante de Fígado/efeitos adversos , Micoses/prevenção & controle , Complicações Pós-Operatórias , Rejeição de Enxerto/etiologia , Humanos , Micoses/microbiologia
13.
Br J Surg ; 100(8): 991-1001, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23754643

RESUMO

BACKGROUND: Adequate preservation of renal allografts for transplantation is important for maintaining and improving transplant outcomes. There are two prevalent methods: hypothermic machine perfusion and static cold storage. The preferred method of storage, however, remains controversial. The objective was to review systematically the evidence comparing outcomes from these two modalities. METHODS: A literature search was performed using MEDLINE, Embase, the Cochrane Library, the Transplant Library and the International Clinical Trials Registry Platform. The final date for searches was 30 November 2012. Studies were assessed for methodological quality. Summary effects were calculated as relative risk (RR) with 95 per cent confidence interval (c.i.). Randomized clinical trials (RCTs) and non-RCTs were included, but evaluated separately. Results from RCTs alone were used for meta-analysis. RESULTS: Eighteen studies met the inclusion criteria, including seven RCTs (1475 kidneys) and 11 non-RCTs (728 kidneys). The overall risk of delayed graft function was lower with hypothermic machine perfusion than static cold storage (RR 0·81, 95 per cent c.i. 0·71 to 0·92; P = 0·002). There was no difference in the rate of primary non-function (RR 1·15, 0·46 to 2·90; P = 0·767). There was a faster initial fall in the level of serum creatinine with hypothermic machine perfusion in two RCTs, but not in another. There was no relationship between rates of acute rejection or patient survival and the method of preservation. CONCLUSION: Data from the included studies suggest that hypothermic machine perfusion reduces delayed graft function compared with static cold storage. There was no difference in primary non-function, acute rejection, long-term renal function or patient survival. A difference in renal graft survival is uncertain.


Assuntos
Função Retardada do Enxerto/etiologia , Hipertermia Induzida/métodos , Transplante de Rim/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Desenho de Equipamento , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/fisiologia , Humanos , Hipertermia Induzida/instrumentação , Ensaios Clínicos Controlados Aleatórios como Assunto , Transplante Homólogo , Resultado do Tratamento
14.
J Neuroendocrinol ; 24(8): 1135-43, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22458414

RESUMO

Sex steroid hormones, such as progesterone, have been shown to display neuroprotective properties after various models of central nervous system injury, including cerebral ischaemia, although the mechanism(s) of action remain largely undetermined. Allopregnanolone, an active progesterone metabolite, may explain some of the protective actions of progesterone. We utilised an in vitro model of ischaemia to evaluate the neuroprotective potential of allopregnanolone and examine its interaction at the GABA(A) receptor, which is hypothesised to be its main neuroprotective mechanism. In adult male mouse coronal caudate slices exposed to oxygen glucose deprivation (OGD), we measured aspects of OGD-induced dopamine release, which is neurotoxic during ischaemia, using fast cyclic voltammetry and also assessed tissue viability. The GABA(A) agonist, muscimol, displayed a neuroprotective profile in terms of delaying the OGD-evoked dopamine efflux (P < 0.05) and reducing the amount of dopamine released after OGD (P < 0.05). Allopregnanolone, at a concentration of 10(-6) m, also displayed a neuroprotective profile because it significantly reduced the amount of dopamine efflux (P < 0.05) and reduced the loss of viable tissue after OGD compared to slices exposed to vehicle during OGD (P < 0.05). However, the effect of 10(-6) m allopregnanolone on dopamine efflux was prevented in the presence of bicuculline, a competitive GABA(A) receptor antagonist. These results describe the use of an in vitro model of ischaemia with respect to determining that allopregnanolone is neuroprotective during the acute phase of ischaemia, and also demonstrate that such actions are dependent, at least in part, upon interaction at the GABA(A) receptor.


Assuntos
Isquemia Encefálica/patologia , Corpo Estriado/efeitos dos fármacos , Dopamina/toxicidade , Pregnanolona/farmacologia , Receptores de GABA-A/metabolismo , Animais , Isquemia Encefálica/metabolismo , Corpo Estriado/patologia , Dopamina/metabolismo , Agonistas GABAérgicos/farmacologia , Técnicas In Vitro , Masculino , Camundongos , Receptores de GABA-A/efeitos dos fármacos
15.
Am J Transplant ; 12(4): 896-906, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22221739

RESUMO

Static cold storage is the most prevalent method for renal allograft preservation. Several solutions have been designed to counteract the detrimental effects of cold ischemia and reperfusion. The aim of this study was to appraise the evidence for the currently available preservation solutions. We performed a systematic literature search using MEDLINE, EMBASE, the Cochrane Library, the Transplant Library and trial registries. Inclusion criteria specified any comparative, prospective study for deceased donor renal allografts. Studies were assessed for methodological quality. The primary outcome was delayed graft function (DGF). Fifteen trials with a total of 3584 kidneys were included. Eurocollins was associated with a higher risk of DGF than University of Wisconsin solution (UW) in two randomized controlled trials (RCTs) and histidine-tryptophan-ketoglutarate (HTK) in two RCTs. UW was associated with an equal risk of DGF compared with Celsior in three RCTs and HTK in two RCTs. There was limited data regarding other comparisons and outcomes. The choice of preservation solution has an effect on the incidence of DGF, which might, in turn, affect long-term outcomes. Both UW and HTK have lower rates of DGF than Eurocollins. There is no difference in the incidence of DGF with the use of Celsior, HTK and UW. These findings are supported by registry data.


Assuntos
Criopreservação/métodos , Transplante de Rim , Soluções para Preservação de Órgãos/uso terapêutico , Preservação de Órgãos/métodos , Ensaios Clínicos como Assunto , Isquemia Fria , Função Retardada do Enxerto/fisiopatologia , Sobrevivência de Enxerto , Humanos , Rim/fisiopatologia , Taxa de Sobrevida , Transplante Homólogo
16.
J Contam Hydrol ; 115(1-4): 46-63, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20444520

RESUMO

The behavior of dense, viscous calcium bromide brine solutions used to remediate systems contaminated with dense nonaqueous phase liquids (DNAPLs) is considered in laboratory and field porous medium systems. The density and viscosity of brine solutions are experimentally investigated and functional forms fit over a wide range of mass fractions. A density of 1.7 times, and a corresponding viscosity of 6.3 times, that of water is obtained at a calcium bromide mass fraction of 0.53. A three-dimensional laboratory cell is used to investigate the establishment, persistence, and rate of removal of a stratified dense brine layer in a controlled system. Results from a field-scale experiment performed at the Dover National Test Site are used to investigate the ability to establish and maintain a dense brine layer as a component of a DNAPL recovery strategy, and to recover the brine at sufficiently high mass fractions to support the economical reuse of the brine. The results of both laboratory and field experiments show that a dense brine layer can be established, maintained, and recovered to a significant extent. Regions of unstable density profiles are shown to develop and persist in the field-scale experiment, which we attribute to regions of low hydraulic conductivity. The saturated-unsaturated, variable-density groundwater flow simulation code SUTRA is modified to describe the system of interest, and used to compare simulations to experimental observations and to investigate certain unobserved aspects of these complex systems. The model results show that the standard model formulation is not appropriate for capturing the behavior of sharp density gradients observed during the dense brine experiments.


Assuntos
Brometos/química , Compostos de Cálcio/química , Recuperação e Remediação Ambiental/métodos , Porosidade , Sais/química , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Recuperação e Remediação Ambiental/economia , Modelos Teóricos , Soluções/química , Gravidade Específica , Viscosidade , Abastecimento de Água/análise
17.
Mol Imaging Biol ; 11(6): 473-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19330385

RESUMO

PURPOSE: To evaluate prognostic value of integrated 2-deoxy-2-[F-18]fluoro-D: -glucose-positron emission tomography/computed tomography (FDG-PET/CT) and correlate histopathological subtype with maximum standardized uptake value (SUV(max)) and survival in patients with malignant mesothelioma (MM). PROCEDURES: Retrospective review of FDG-PET/CT scans, with derivation of SUV(max) of FDG-avid lesions, was performed in patients with biopsy-proven MM. Clinical follow-up and Kaplan-Meier survival analysis was performed. RESULTS: Forty-six patients (37 M:9 F; mean age 61 years) with MM had a FDG-PET/CT scan in a 30-month period. Follow-up was available on 44/46 (96%) patients. Metastatic disease was detected in 9/46 (20%) patients on FDG-PET/CT, where 8/9 were previously undetected. Better survival was found in patients without metastases (p value < 0.05). Mean SUV(max) of primary pleural lesions in patients with metastatic disease was significantly higher than in patients without metastatic disease (p value < 0.05). Progression-free survival was significantly better in the epithelioid histology group compared to the biphasic group (p value 0.015). CONCLUSIONS: Detection of extrathoracic metastases on FDG-PET/CT and nonepithelioid histopathology are poor prognostic indicators in patients with MM.


Assuntos
Fluordesoxiglucose F18 , Mesotelioma/patologia , Neoplasias Pleurais/patologia , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Intervalo Livre de Doença , Feminino , Fluordesoxiglucose F18/metabolismo , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Mesotelioma/diagnóstico por imagem , Pessoa de Meia-Idade , Neoplasias Pleurais/diagnóstico por imagem , Prognóstico , Radiografia , Compostos Radiofarmacêuticos/metabolismo , Fatores de Tempo
18.
Br J Surg ; 94(11): 1319-30, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17939138

RESUMO

BACKGROUND: The acceptance of liver transplantation in the management of hepatic malignancy declined after early poor outcomes. Despite recent developments, including stricter selection criteria and improved adjuvant therapies, the role of liver transplantation in the management of cancer remains controversial. This review explores the evidence for the current role of liver transplantation in the management of hepatic malignancy in the context of recent advances in surgical resection and non-surgical treatments. METHODS: A literature search was conducted using the Cochrane Library and Ovid MEDLINE and EMBASE, using terms for hepatic malignancy and interventions that included liver transplantation, percutaneous interventions, chemotherapy and surgical resection. RESULTS AND CONCLUSION: In patients with primary hepatocellular carcinoma, improved selection has led to outcomes equivalent to those from surgical resection and comparable to those in patients transplanted for non-malignant indications. Recent studies suggest that selection criteria may be refined further. Surgical resection or percutaneous therapies may reduce the risk of progression while waiting for a transplant. Recent improvements have occurred in neoadjuvant therapies for cholangiocarcinoma. Nevertheless, a number of questions regarding the role of liver transplantation for hepatic malignancy remain.


Assuntos
Carcinoma Hepatocelular/cirurgia , Colangiocarcinoma/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Humanos , Transplante de Fígado/tendências , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Intern Med J ; 37(11): 753-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17517082

RESUMO

BACKGROUND: Accurate staging of lung cancer is essential in determining the most appropriate management plan, as detection of occult metastasis can significantly alter management. AIMS: The aims of this study are to determine the prevalence of occult metastasis in patients undergoing 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET) for evaluation of suspected/proven lung carcinoma and correlate pre-PET TNM stage with prevalence of metastasis. METHODS: FDG-PET, which identified patients with metastasis on institutional database, was re-evaluated by a nuclear medicine physician blinded to clinical information. The confidence level of metastasis was scored on a 5-point scale, with a score of >/=4 considered positive. RESULTS: There were 67 of 645 (10%) patients identified with suspected occult metastasis on FDG-PET. Twelve patients scoring

Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Metástase Neoplásica/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Valor Preditivo dos Testes , Prevalência , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Nódulo Pulmonar Solitário/patologia
20.
Ann Thorac Surg ; 71(2): 452-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11235687

RESUMO

BACKGROUND: This study aims to assess the efficacy of video-assisted thoracoscopic surgery pleurodesis in the treatment of spontaneous pneumothorax with particular reference to the rate of recurrence after abrasion pleurodesis and postoperative neuralgia. METHODS: One hundred one patients who underwent 109 video-assisted thoracoscopic surgery pleurodesis procedures in the Austin & Repatriation Medical Centre between January 1992 and June 1998 were identified from a computerized database. The follow-up period was from 8 months to 7 years and 1 month (mean, 44.4 months). Patients were telephoned and asked as to whether recurrence occurred, and if so, when it occurred and how it was treated. They were asked to grade their current pain level from 0 to 6. RESULTS: Eighty-two patients were contacted, corresponding to 88 video-assisted thoracoscopic surgery pleurodesis procedures that were followed up (80.7%). There were five recurrences (5.7%). The pain level was rated as 0 in 64 cases (72.7%), 1 in 27 cases (23.9%), 2 in 1 case (1.1%), and 3 in 2 cases (2.3%). CONCLUSIONS: These data suggest that video-assisted thoracoscopic surgery pleurodesis is a valid alternative to thoracotomy with pleurectomy for treatment of spontaneous pneumothorax with an acceptable recurrence rate and minimal amount of postoperative neuralgia.


Assuntos
Pleurodese , Pneumotórax/cirurgia , Cirurgia Torácica Vídeoassistida , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Complicações Pós-Operatórias/etiologia , Recidiva , Resultado do Tratamento
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