Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed May 16, 2007). PDF text: x, 248 p. : ill. (some col.) ; 4.25Mb. UMI publication number: AAT 3237054. Includes bibliographical references. Also available in microfilm and microfiche formats.

Though now seen everywhere in the hospital and operating theater, there was a time when surgeons used no hand protection. In the late 19th century, however, as the science of bacteriology became more advanced, surgical glove usage spurred. Today, gloves serve an extremely important role, helping to maintain the sterile field and protect hospital staff from the transfer of bloodborne pathogens. Since they are so valuable, it is equally important that gloves fit properly as to not be detrimental to the surgeon. Gloves that are too tight increase fatigue rate and decrease fine finger dexterity. Gloves that are too loose can reduce tactile sensitivity caused by bunching of material at the fingers. Traditionally, the larger of measurement of hand circumference and hand length are used to determine glove size, but most select a size based on comfort of fit. To assist manufacturers with creating certain sizes, anthropometry is often used. Anthropometry is the study of the physical measures of the human body. Human-factors engineering is the science of applying anthropometric information to the design of devices intended for human use. In this study, two anthropometric databases, studies by Greiner and Pheasant, were utilized to obtain hand measurements representative of the general population, due to the population studied. For this study, 59 general surgeons (51 male, 8 female) were invited on separate dates to the Medtronic Minimally Invasive Therapies Group in North Haven, CT for Voice of Customer laboratories. While there, they completed surveys where they listed their preferred glove size, double gloving sizes, dominant hand, etc. In addition, the following six measurements were taken: hand circumference, maximum grip diameter, Digit 1 (D1) length, Digit 2 (D2) link length, Distance from D2 Metacarpo-phalangeal (MCP) to Distal Interphalangeal (DIP) joint, and D2 distal phalanx length (extrapolated). These measurements were averaged and compared to the numbers reported in the Greiner and Pheasant studies for analysis using a novel Microsoft Excel tool. Commonly used laparoscopic staplers were also measured to assess ergonomic usability amongst the surgeon population. Male surgeons had statistically significantly larger hands than female surgeons with respect to all measurements taken. Compared to men of the general population, male surgeons had significantly smaller grip diameter, D2 link length, yet a greater D1 Length. Compared to women of the general population, female surgeons had a greater hand circumference, yet smaller D2 link length. All other measurements recorded were statistically equivalent. In general, surgeons seem to select a preferred glove size based on their hand circumference (Pearson’s Correlation 0.799, R2 63.9%), followed by D2 Link Length (Pearson’s Correlation 0.631, R2 39.9%). The median glove size for male surgeons was 7.5 (0.50) and 6.0 (0.25) for female surgeons (p > 0.001). To evaluate the ergonomic usability of laparoscopic staplers, the measurement “Distance from D2 MCP to DIP joint” was developed internally to roughly assess effective trigger distance, where larger lengths would force the user to adjust their hand position. The handles of two commonly used laparoscopic staplers were measured to determine what proportion of the surgeon population could use them effectively. Based on these measurements, for the Medtronic Endo GIA™ Ultra Stapler, nearly all male surgeons and 99.8% of female surgeons could use it ergonomically. For the Ethicon ECHELON FLEX™ ENDOPATH® Stapler, only 78.2% of male surgeons and 30.9% of female surgeons could use it ergonomically. This study demonstrated that there exists a large amount of variability between each part of the hand based on the different measurements. Therefore, to best assure proper fitting gloves for the majority of users, a two metric system involving hand circumference and finger length would be useful to accommodate the inherent variability of the hand. With respect to laparoscopic stapling platforms, this study demonstrated that the instruments are simply too large to be used ergonomically by a large portion of the intended audience. Medical device manufacturers should look to create an adjustable handle such that the trigger distance can be manipulated to fit the needs of those surgeons with smaller hands.

Conventionally performed equine ovariohysterectomy (OHE) is a technically demanding surgery associated with a high degree of invasiveness and morbidity. Hand-assisted laparoscopic surgical technique allows introduction of a hand through a portal into the laparoscopic field to facilitate surgical manipulation while maintaining abdominal insufflation and laparoscopic visualization. The purpose of this study was to develop and evaluate a hand-assisted laparoscopic OHE technique for dorsally recumbent horses. The surgical technique was developed in terminal (2 mares) and subsequently evaluated in 6 survival procedures. Mares were fasted 48 hours, anesthetized and positioned in dorsal recumbency for laparoscopic surgery. A hand access device (Omniport) was placed in a caudal midline laparotomy followed by 4 laparoscopic portals. Transection of the ovarian pedicle and broad ligament was achieved using a combination of a laparoscopic stapling instrument, an ultrasonically activated instrument and endoscopic clips. The genital tract was exteriorized through the laparotomy, and the body of the uterus transected and sutured in conventional pattern. Horses were evaluated through postoperative day 14 when a post mortem evaluation was performed. Four mares recuperated well after surgery, 1 mare was euthanized due to bilateral femur fractures sustained during anesthetic recovery and another developed severe pleuropneumonia. At necropsy all but one abdominal incision was healing routinely. One mare had abscessed along the laparotomy incision and developed visceral adhesions. Uncomplicated healing of transected mesovarial, mesometrial and uterine remnants was observed in all recovered mares. Hand-assisted laparoscopic OHE technique represents a minimally invasive and technically feasible alternative for conventional OHE. Careful patient selection and preparation may reduce the complications observed in this study. / Master of Science

Minimally invasive surgery (MIS) is becoming increasing popular and widely adopted on account of relative post-operative advantages (shorter hospital stays, less scarification, trauma and post-operative pain) it offers patients when compared to open surgery. Nonetheless, the surge in demand for MIS procedures are not met with commensurate availability of experts in the field, thus leading to excessive stress attributable to increased case load, and an increase in the number of surgery interns requiring training with far less MIS experts to provide it. Also, musculoskeletal discomforts experienced by MIS surgeons have been attributed to ergonomic factors among other causes, and a required verification of the viability of fundamentals of laparoscopic surgery (FLS) as a valid ergonomic discriminator between traditional MIS and robot-assisted MIS was tested and validated. Real-time, subject-centered, and objective quantification of surgical skills has long been a challenge. A proposed solution is presented here involving the application of complexity theory (time delay and Hurst exponent principles) to the analysis of phase space reconstructions of time series data, generated by periodic changes in Euler coordinates of surgical graspers while being used by MIS novices and experts. A comparison of Hurst exponent and time delay values over multiple iterations of the same task provides quantitative insight on MIS skills improvement and experience.

No description available.

Laparoscopic surgery for colorectal cancer was first reported in 1991. However, early experiences with laparoscopic colectomy were unfavorable, with higher than expected rates of port-site recurrence and concerns about compromised long-term oncologic outcomes. These concerns have been resolved by the results of several large-scale European and American multicenter randomized controlled trials (RCTs) that reported no difference in oncologic clearance and survival between laparoscopic and open colectomy for colon cancer. / The role of laparoscopic surgery for rectal cancer, on the other hand, still remains controversial. Because laparoscopic surgery for rectal cancer is technically more difficult and has a higher morbidity rate than laparoscopic colectomy for colon cancer, most of the published large-scale multicenter RCTs comparing laparoscopic and open colorectal cancer did not include patients with rectal cancer. To date, good-quality data comparing laparoscopic and open surgery for rectal cancer are still scarce in the literature. The main objective of this thesis is to provide additional evidence to justify the role of laparoscopic surgery for rectal cancer. / To be justified, laparoscopic surgery for rectal cancer should have equal or better clinical outcomes than open surgery and improve quality of life. Furthermore, oncologic clearance as well as long-term survival should not be adversely affected by the laparoscopic approach. / In this thesis, a series of RCTs and comparative studies with long-term follow-up were conducted to address the above issues. Our results demonstrate that laparoscopic surgery for rectal cancer is associated with earlier postoperative recovery, better preservation of urosexual function and quality of life, and less late morbidity when compared with open surgery. Oncologic clearance in terms of resection margins and number of lymph nodes harvested are comparable between the laparoscopic and open groups. Most importantly, laparoscopic surgery does not adversely affect disease control or jeopardize long-term survival of rectal cancer patients. The benefits of the laparoscopic over the open approach remain the same regardless of the types of rectal cancer surgery (laparoscopic-assisted anterior resection, total mesorectal excision, or abdominoperineal resection) or the location of the tumor. It is therefore concluded that laparoscopic surgery for rectal cancer is safe and justified. Based on our results, we believe that laparoscopic surgery can be regarded as an acceptable alternative to open surgery for treating curable rectal cancer. / Ng, Siu Man Simon. / Thesis (M.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 323-366). / Dedication --- p.1 / Declaration of Originality --- p.2 / Abstract --- p.3 / Table of Contents --- p.5 / List of Tables --- p.8 / List of Figures --- p.10 / List of Abbreviations --- p.13 / PRÉCIS TO THE THESIS --- p.15 / Chapter PART I --- BACKGROUND --- p.37 / Chapter Chapter 1 --- Management of Colorectal Cancer: From Open to Laparoscopic Surgery --- p.38 / Chapter 1.1 --- Introduction to Colorectal Cancer --- p.39 / Chapter 1.2 --- A Brief History of Laparoscopic Surgery --- p.51 / Chapter 1.3 --- Laparoscopic Colorectal Surgery: The Beginning --- p.58 / Chapter 1.4 --- Evidence for the Safety and Efficacy of Laparoscopic Surgery for Colon Cancer --- p.62 / Chapter Chapter 2 --- Laparoscopic Surgery for Rectal Cancer: A Critical Appraisal of Published Literature --- p.71 / Chapter 2.1 --- Introduction --- p.72 / Chapter 2.2 --- Evidence from Single-Center Trials --- p.76 / Chapter 2.3 --- Evidence from Multicenter Trials --- p.82 / Chapter 2.4 --- Ongoing Trials --- p.89 / Chapter 2.5 --- Discussion --- p.92 / Chapter Chapter 3 --- Laparoscopic Surgery for Rectosigmoid and Rectal Cancer: Experience at The Prince of Wales Hospital, Hong Kong --- p.97 / Chapter 3.1 --- The Beginning of Laparoscopic Era in Hong Kong --- p.98 / Chapter 3.2 --- Early Experience of Laparoscopic Colorectal Surgery --- p.102 / Chapter 3.3 --- Nonrandomized Comparative Studies --- p.105 / Chapter 3.4 --- The Hong Kong Trial --- p.110 / Chapter PART II --- HYPOTHESES AND CLINICAL STUDIES --- p.116 / Chapter Chapter 4 --- Research Hypotheses and Objectives --- p.117 / Chapter 4.1 --- Research Hypotheses --- p.118 / Chapter 4.2 --- Research Plan and Objectives --- p.120 / Chapter Chapter 5 --- Laparoscopic-Assisted Versus Open Anterior Resection for Upper Rectal Cancer: Short-Term Outcomes --- p.122 / Chapter 5.1 --- Abstract --- p.123 / Chapter 5.2 --- Introduction --- p.125 / Chapter 5.3 --- Patients and Methods --- p.128 / Chapter 5.4 --- Results --- p.133 / Chapter 5.5 --- Discussion --- p.144 / Chapter 5.6 --- Conclusions --- p.148 / Chapter Chapter 6 --- Laparoscopic-Assisted Versus Open Anterior Resection for Upper Rectal Cancer: Long-Term Morbidity and Oncologic Outcomes --- p.149 / Chapter 6.1 --- Abstract --- p.150 / Chapter 6.2 --- Introduction --- p.152 / Chapter 6.3 --- Patients and Methods --- p.154 / Chapter 6.4 --- Results --- p.158 / Chapter 6.5 --- Discussion --- p.173 / Chapter 6.6 --- Conclusions --- p.179 / Chapter Chapter 7 --- Laparoscopic-Assisted Versus Open Abdominoperineal Resection for Low Rectal Cancer --- p.180 / Chapter 7.1 --- Abstract --- p.181 / Chapter 7.2 --- Introduction --- p.183 / Chapter 7.3 --- Patients and Methods --- p.185 / Chapter 7.4 --- Results --- p.190 / Chapter 7.5 --- Discussion --- p.201 / Chapter 7.6 --- Conclusions --- p.207 / Chapter Chapter 8 --- Laparoscopic-Assisted Versus Open Total Mesorectal Excision with Anal Sphincter Preservation for Mid and Low Rectal Cancer --- p.208 / Chapter 8.1 --- Abstract --- p.209 / Chapter 8.2 --- Introduction --- p.211 / Chapter 8.3 --- Patients and Methods --- p.214 / Chapter 8.4 --- Results --- p.221 / Chapter 8.5 --- Discussion --- p.238 / Chapter 8.6 --- Conclusions --- p.246 / Chapter Chapter 9 --- Long-Term Oncologic Outcomes of Laparoscopic Versus Open Surgery for Rectal Cancer: A Pooled Analysis of Three Randomized Controlled Trials --- p.247 / Chapter 9.1 --- Abstract --- p.248 / Chapter 9.2 --- Introduction --- p.250 / Chapter 9.3 --- Patients and Methods --- p.254 / Chapter 9.4 --- Results --- p.258 / Chapter 9.5 --- Discussion --- p.272 / Chapter 9.6 --- Conclusions --- p.280 / Chapter Chapter 10 --- Prospective Comparison of Quality of Life Outcomes After Curative Laparoscopic Versus Open Sphincter-Preserving Resection for Rectal Cancer --- p.281 / Chapter 10.1 --- Abstract --- p.282 / Chapter 10.2 --- Introduction --- p.284 / Chapter 10.3 --- Patients and Methods --- p.287 / Chapter 10.4 --- Results --- p.292 / Chapter 10.5 --- Discussion --- p.308 / Chapter Chapter 11 --- Conclusions --- p.314 / Chapter 11.1 --- Conclusions --- p.315 / REFERENCES --- p.322 / LIST OF PUBLICATIONS RELATED TO THE THESIS --- p.367 / ACKNOWLEDGEMENTS --- p.373

Colorectal cancer is one of the commonest malignancies worldwide. Its prevention, diagnosis and treatments have attracted multidisciplinary attention. Surgery is the mainstay of treatment for colorectal cancer. It was estimated that up to 85% of colorectal cancer were amenable to surgical treatment, whether curative or palliative. Not surprisingly laparoscopic resection of colorectal cancer was reported soon after cholecystectomy. However, with the appearance of early port site recurrence, most authorities were concerned about the adequacy of tumour clearance and the long-term survival after laparoscopic resection. / In this thesis, comparative and randomized studies were conducted to answer the above questions. It was concluded that, as compared to conventional open surgery, laparoscopic assisted resection of recto-sigmoid carcinoma was less painful and allowed earlier post-operative recovery. Tissue trauma, as reflected by systemic cytokines response, was less after laparoscopic assisted resection. Some cellular components of immune system were also less suppressed. Most importantly, laparoscopic resection did not jeopardize the survival and disease control of patients. The justification of adopting laparoscopic technique would depend on the societal value of its effectiveness in improving the short-term post-operative outcomes. / Laparoscopic technology and its application may be the biggest advancement in nearly all surgical specialties in the last decade. Since the introduction of laparoscopic cholecystectomy, enthusiastic surgeons have attempted laparoscopic approach in almost every type of operations, and many of the techniques have gained public acceptance within a very short time. However, most of these developments were not based on good scientific evidence from comparative study. While laparoscopic cholecystectomy was shown to cause less pain and allow patients to recover earlier after operation, these benefits may or may not be conferred to other procedures and diseases. / Therefore, to justify the use of laparoscopic assisted colorectal resection for carcinoma, two criteria must be satisfied. Firstly the long term survival and the disease free interval of patients should not be adversely affected, as these are the most important endpoints in the success of tumour surgery. Secondly, the proposed benefits of minimally invasive surgery must be demonstrated, otherwise it is not worthwhile to adopt a new technique. / Leung Ka Lau. / "July 2005." / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0174. / Thesis (M.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 122-155). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / School code: 1307.

Background: Surgical checklists are in use as means to reduce errors for safer surgery. Checklists are infrequently applied during procedures and have been limited to lists of procedural steps as aid memoires. Aims: We aimed to formulate a performance based checklist and to study its effect on the surgical task performance of novice surgeons when applied during both, routine knot tying and simulated emergency laparoscopic tasks. We also aimed to study the effect of the performance based intra-procedural checklist in clinical environments during elective laparoscopic procedures as a way of error reduction mechanism and improvement of patient safety. Methods: The study was conducted in two settings, lab-based and clinical-based environments. The lab-based study was conducted during both routine and emergency tasks. Lab-based study- routine task: Twenty novices were randomised into two equal groups, those receiving paper feedback (control group), and those receiving paper feedback and the checklist that was applied at 20 seconds intervals (checklist group). The task involved performing laparoscopic double knots which were repeated over 5 separate stages. Human reliability assessment technique was used for error analysis on unedited video recordings of the tasks. Endpoints included number of errors, error probability (number of errors/number of knots), error types and number of completed knots. Non-parametric statistics were used for data analysis. Lab-based- emergency task: Thirty consented laparoscopic novices were exposed unexpectedly to a bleeding vessel in a laparoscopic virtual reality simulator as an emergency surgical scenario. The task consisted of using laparoscopic clips to achieve haemostasis. Subjects were randomly allocated into 2 equal groups; those using the checklist (checklist group) and those without (control group). The checklist was applied by the trainees in the checklist group at 20 seconds intervals. The surgical performance was computed on eight predetermined technical factors. Clinical-based study: Surgical trainees in the general surgery at Tayside NHS were included in this study and required the attendance of a trainer during the procedure as per routine practice. Record year of trainees and previous experience on laparoscopic cholecystectomy were noted. Two elective laparoscopic cholecystectomies for each trainee were video-recorded without the use of the checklist, directly followed by 2 further operations after the introduction of the checklist. The unedited videos were analysed for error detection using human reliability analysis technique. Total number of errors per time during each procedure, total number of errors per number of instrument movements, total number of instrument movements per time and number of trainer intervention while per time were noted as assessment points. Results: Lab-based- routine task: 2341 errors were detected in 141 tasks, 408 subtasks and 2249 steps during the 5 stages. During the first stage, the errors were not significantly different between groups. The checklist group committed significantly fewer errors as compared to the control group during all the later 4 stages (p < 0.01). The checklist group had an enhanced learning curve as the last 4 stages showed significant fewer errors compared to the first stage (p < 0.05), while the control group showed no improvement. Error probability was significantly higher in the control group compared to the checklist group: median [IQR] 32.6 [25.89] vs 11.7 [10.72] (p < 0.01). Individual error types during each step of the laparoscopic task were identified. The checklist group performed better with fewer errors for all the error types. While, there was no significant difference in each of 'the lack of supination', 'tissue bite' and 'out of vision'; the differences in all the rest of error types were highly statistically significant (p < 0.01). Number of completed knots was not statistically different between the 2 groups. Lab-based- emergency task: The checklist group performed significantly better in 6 out of 8 technical factors when compared to the control group median [IQR]: Right instrument path length (m) 1.44 [1.22] vs 2.06 [1.70] (p= 0.029), and right instrument angular path (degree) 312.10 [269.44] vs 541.80 [455.16] (p= 0.014), left instrument path length (m) 1.20 [0.60] vs 2.08 [2.02] (p= 0.004), left instrument angular path (degree) 277.62 [132.11] vs 385.88 [428.42] (p= 0.017). The checklist group committed significantly fewer number of errors in the number of badly placed clips (p= 0.035) and number of dropped clips (p= 0.012). Although statistically not significant, total blood loss (lit) decreased in the checklist group from 0.83 [1.23] to 0.78 [0.28] (p= 0.724), and total time (sec) from 186.51 [145.69] to 125.14 [101.46] (p=0.165). Clinical-based study: Participants performed statistically better with fewer number of errors per time with the application of the checklist compared to when no checklist was used respectively: Median [IQR] total number of errors 1.51 [0.80] vs 3.84 [1.42] (p=0.002), consequential errors 0.20 [0.12] vs 0.45 [0.42] (P=0.005), inconsequential errors 1.32 [0.75] vs 3.27 [1.48] (p=0.006) and total number of errors per number of instrument movements 0.16 [0.04] vs 0.29 [0.16] (p= 0.003). With the introduction of the checklist, the number of interventions by the trainer per time decreased from 2.79 [1.85] to 0.43 [1.208] (p=0.003) and the number of instrument movements per time decreased from 11.90 [5.34] to 10.38 [5.16] (p=0.04). Conclusions: We have developed standardised checklists to be applied during elective and emergency laparoscopic tasks. The performance based self-administered intra-procedural checklist had a significant accelerating effect on the acquisition of technical skills when applied by novices during a standardised laparoscopic lab-based routine task and improved the task performance during a simulated laparoscopic emergency scenario. The checklist enhanced the performance of surgical trainees and decreased the number of interventions of the trainer during laparoscopic cholecystectomy.

published_or_final_version / Surgery / Master / Master of Surgery

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