published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Thesis (M.Med.Sc.)--University of Hong Kong, 2008. / Includes bibliographical references (p. 39-45).

No description available.

The purpose of this study is to determine if early laparoscopic cholecystectomy in patients with uncomplicated gallstone disease and symptoms of dyspepsia will produce complete symptomatic resolution 1 year postoperatively and to identify appropriate timing of laparoscopic cholecystectomy to decrease cholecystectomy failure rate. Specific research objectives were to determine: <p>1) if laparoscopic cholecystectomy in patients with gallstones and symptoms of dyspepsia will achieve complete symptomatic relief; <p>2) the change in the preoperative score to the postoperative score and satisfaction after laparoscopic cholecystectomy for the two groups: patients with gallstones and symptoms of dyspepsia and the patients with gallstones and no dyspepsia; <p>3) the relationship between the duration of preoperative episodes and the probability of complete resolution of symptoms with laparoscopic cholecystectomy in patients with gallstones and symptoms of dyspepsia; <p>4) the relationship between the frequency of preoperative episodes and the probability of complete resolution of symptoms with early laparoscopic cholecystectomy in patients with gallstones and symptoms of dyspepsia and <p>5) the differences in pathologic findings between patients with gallstones and no symptoms of dyspepsia versus patients with symptoms of dyspepsia.<p>The methods included a retrospective chart review for patient identification, a follow up survey and microscopic pathological examination of gallbladder specimens. Nine hundred and forty two patients entered the study. Three hundred and fifty nine surveys were returned producing a response rate of 43%. Two hundred and sixty four patients (77.0%) had symptoms of dyspepsia (Group I) and 79 patients (23.0%) had no symptoms of dyspepsia (Group II). <p>Laparoscopic cholecystectomy for patients with gallstones and symptoms of dyspepsia does not achieve complete symptomatic relief 1 year after surgery. The frequency and duration of preoperative episodes have no relation to the outcome of surgery. The majority of patients in both Groups (I, II) were found to have morphological evidence of acute cholecystitis and only a small number had chronic cholecystitis. Group I had a greater reduction in the Buckley score than Group II after LC but had similar rates of satisfaction from surgery.

The purpose of this study is to determine if early laparoscopic cholecystectomy in patients with uncomplicated gallstone disease and symptoms of dyspepsia will produce complete symptomatic resolution 1 year postoperatively and to identify appropriate timing of laparoscopic cholecystectomy to decrease cholecystectomy failure rate. Specific research objectives were to determine: <p>1) if laparoscopic cholecystectomy in patients with gallstones and symptoms of dyspepsia will achieve complete symptomatic relief; <p>2) the change in the preoperative score to the postoperative score and satisfaction after laparoscopic cholecystectomy for the two groups: patients with gallstones and symptoms of dyspepsia and the patients with gallstones and no dyspepsia; <p>3) the relationship between the duration of preoperative episodes and the probability of complete resolution of symptoms with laparoscopic cholecystectomy in patients with gallstones and symptoms of dyspepsia; <p>4) the relationship between the frequency of preoperative episodes and the probability of complete resolution of symptoms with early laparoscopic cholecystectomy in patients with gallstones and symptoms of dyspepsia and <p>5) the differences in pathologic findings between patients with gallstones and no symptoms of dyspepsia versus patients with symptoms of dyspepsia.<p>The methods included a retrospective chart review for patient identification, a follow up survey and microscopic pathological examination of gallbladder specimens. Nine hundred and forty two patients entered the study. Three hundred and fifty nine surveys were returned producing a response rate of 43%. Two hundred and sixty four patients (77.0%) had symptoms of dyspepsia (Group I) and 79 patients (23.0%) had no symptoms of dyspepsia (Group II). <p>Laparoscopic cholecystectomy for patients with gallstones and symptoms of dyspepsia does not achieve complete symptomatic relief 1 year after surgery. The frequency and duration of preoperative episodes have no relation to the outcome of surgery. The majority of patients in both Groups (I, II) were found to have morphological evidence of acute cholecystitis and only a small number had chronic cholecystitis. Group I had a greater reduction in the Buckley score than Group II after LC but had similar rates of satisfaction from surgery.

Background and purposes: Carbon dioxide is the common gas material to establish pneumoperitoneum to provide working space for laparoscopic surgeries, but possesses risks of reduced cardiac output and hypercarbia in cases with limited cardiopulmonary reserve. For such cases, we design a novel trocar to reduce the intrabdominal pressure, so as to perform the same operation safely. Animals and Methods: The novel trocar has four flexible leaflets that can be fixed as ¡§extended status¡¨ to hold the inner surface of abdominal wall. When the trocar was tracted upward with iron wires, the abdominal wall can be elevated. The lowest pressure of pneumoperitoneum with the usage of the novel trocar was tested first. We found the pressure was dependent on the target organ. Laparoscopic cholecystectomy was performed to compare the advantage of the novel trocar over the conventional trocar because it is one of the most commonly performed surgeries. Totally 6 pigs were used. They were divided into two groups: 3 pigs as the control group receiving operation with the conventional trocars (group C) under 15 mm Hg pneumoperitoneum, and another 3 with the novel trocar (group N) under 5 mm Hg pneumoperitoneum. Results: The total operation time was significantly longer in group N but the precise dissection time was comparable with group C. No surgical complication was noted in both groups and the blood loss was minimal. The hypercarbia was of a much lesser degree in group N compared to that in group C. Conclusions: Our preliminary data show that with the novel trocar, the laparoscopic cholecystectomy could be smoothly completed under a lesser pressure of 5 mm Hg CO2 pneumoperitoneum in pigs.

Introduction: Despite evidence in favour of cholecystectomy early during first presenting admission for most patients with acute calculous cholecystitis, variation in the timing of cholecystectomy remains evident worldwide. This dissertation characterizes the extent of variation within a large regional healthcare system, as well as addresses gaps in our current understanding of the clinical consequences and costs associated with early versus delayed cholecystectomy for acute cholecystitis. Methods: A population-based retrospective cohort of patients admitted emergently with acute cholecystitis was identified from administrative databases for the province of Ontario, Canada. First, the extent of variation across hospitals in the performance of early cholecystectomy (within 7 days of emergency department presentation) was characterized. Second, among patients discharged without cholecystectomy following index admission, the risk of recurrent gallstone symptoms over time was quantified. Third, operative outcomes of early cholecystectomy were compared to those of delayed cholecystectomy. Finally, a cost-utility analysis compared healthcare costs and quality-adjusted life-year gains associated with three management strategies for acute cholecystitis: early cholecystectomy, delayed cholecystectomy and watchful waiting, where cholecystectomy is performed urgently if recurrent gallstone symptoms arise. Results: The rate of early cholecystectomy varied widely across hospitals in Ontario (median rate 51%, interquartile range 25-71%), even after adjusting for patient characteristics (median odds ratio 3.7). Among patients discharged without cholecystectomy following an index cholecystitis admission, the probability of a gallstone-related emergency department visit or hospital admission was 19% by 12 weeks following discharge. Early cholecystectomy was associated with a lower risk of major bile duct injury (0.28%vs.0.53%, RR=0.53, 95%CI 0.31–0.90, p=0.025). No significant differences were observed in terms of open cholecystectomy (15%vs.14%, RR=1.07, 95%CI 0.99–1.16, p=0.10) or in conversion among laparoscopic cases (11%vs.10%, RR=1.02, 95%CI 0.93–1.13, p=0.68). Early cholecystectomy was on average less costly ($6,905 per person) and more effective (4.20 QALYs per person) than delayed cholecystectomy ($8,511; 4.18 QALYs per person) or watchful waiting ($7,274; 3.99 QALYs per person). Conclusions: Early cholecystectomy offers a benefit over delayed cholecystectomy in terms of major bile duct injury, mitigates the risk of recurrent symptoms, and is associated with the greatest QALY gains at the least cost.

No description available.

Introduction: Despite evidence in favour of cholecystectomy early during first presenting admission for most patients with acute calculous cholecystitis, variation in the timing of cholecystectomy remains evident worldwide. This dissertation characterizes the extent of variation within a large regional healthcare system, as well as addresses gaps in our current understanding of the clinical consequences and costs associated with early versus delayed cholecystectomy for acute cholecystitis. Methods: A population-based retrospective cohort of patients admitted emergently with acute cholecystitis was identified from administrative databases for the province of Ontario, Canada. First, the extent of variation across hospitals in the performance of early cholecystectomy (within 7 days of emergency department presentation) was characterized. Second, among patients discharged without cholecystectomy following index admission, the risk of recurrent gallstone symptoms over time was quantified. Third, operative outcomes of early cholecystectomy were compared to those of delayed cholecystectomy. Finally, a cost-utility analysis compared healthcare costs and quality-adjusted life-year gains associated with three management strategies for acute cholecystitis: early cholecystectomy, delayed cholecystectomy and watchful waiting, where cholecystectomy is performed urgently if recurrent gallstone symptoms arise. Results: The rate of early cholecystectomy varied widely across hospitals in Ontario (median rate 51%, interquartile range 25-71%), even after adjusting for patient characteristics (median odds ratio 3.7). Among patients discharged without cholecystectomy following an index cholecystitis admission, the probability of a gallstone-related emergency department visit or hospital admission was 19% by 12 weeks following discharge. Early cholecystectomy was associated with a lower risk of major bile duct injury (0.28%vs.0.53%, RR=0.53, 95%CI 0.31–0.90, p=0.025). No significant differences were observed in terms of open cholecystectomy (15%vs.14%, RR=1.07, 95%CI 0.99–1.16, p=0.10) or in conversion among laparoscopic cases (11%vs.10%, RR=1.02, 95%CI 0.93–1.13, p=0.68). Early cholecystectomy was on average less costly ($6,905 per person) and more effective (4.20 QALYs per person) than delayed cholecystectomy ($8,511; 4.18 QALYs per person) or watchful waiting ($7,274; 3.99 QALYs per person). Conclusions: Early cholecystectomy offers a benefit over delayed cholecystectomy in terms of major bile duct injury, mitigates the risk of recurrent symptoms, and is associated with the greatest QALY gains at the least cost.

Thesis (M. P. H.)--University of Hong Kong, 2007.