David W. Easter
University of California, San Diego
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Surgical Endoscopy and Other Interventional Techniques | 2009
Santiago Horgan; John Cullen; Mark A. Talamini; Yoav Mintz; Alberto R. Ferreres; Garth R. Jacobsen; Bryan J. Sandler; Julie Bosia; Thomas J. Savides; David W. Easter; Michelle K. Savu; Sonia Ramamoorthy; Emily L. Whitcomb; Sanjay Kumar Agarwal; Emily S. Lukacz; Guillermo Domínguez; Pedro Ferraina
BackgroundNatural orifice translumenal endoscopic surgery (NOTES) has moved quickly from preclinical investigation to clinical implementation. However, several major technical problems limit clinical NOTES including safe access, retraction and dissection of the gallbladder, and clipping of key structures. This study aimed to identify challenges and develop solutions for NOTES during the initial clinical experience.MethodsUnder an Institutional Review Board (IRB)-approved protocol, patients consented to a natural orifice operation for removal of either the gallbladder or the appendix via either the vagina or the stomach using a single umbilical trocar for safety and assistance.ResultsNine transvaginal cholecystectomies, one transgastric appendectomy, and one transvaginal appendectomy have been completed to date. All but one patient were discharged on postoperative day 1 as per protocol. No complications occurred.ConclusionThe limited initial evidence from this study demonstrates that NOTES is feasible and safe. The addition of an umbilical trocar is a bridge allowing safe performance of NOTES procedures until better instruments become available. The addition of a flexible long grasper through the vagina and a flexible operating platform through the stomach has enabled the performance of NOTES in a safe and easily reproducible manner. The use of a uterine manipulator has facilitated visualization of the cul de sac in women with a uterus to allow for safe transvaginal access.
American Journal of Surgery | 2000
Michael Bouvet; Reza Gamagami; Elizabeth A. Gilpin; Oreste Romeo; Aaron R. Sasson; David W. Easter; A. R. Moossa
BACKGROUND The purpose of this study was to determine predictors of survival after resection for periampullary neoplasms. METHODS Over a 15-year period, 208 patients underwent laparotomy for periampullary neoplasms. Data were analyzed to assess predictors of survival. RESULTS Pathologic examination showed pancreatic cancer (n = 136; 65%), ampullary cancer (n = 28; 13%), distal common bile duct cancer (n = 10; 5%), duodenal cancer (n = 4; 2%), neuroendocrine tumor (n = 11; 5%), cystadenocarcinoma (n = 4; 2%), cystadenoma (n = 5; 2%), and other (n = 10; 5%). A total of 129 patients underwent pancreatic resection (71 Whipples, 35 total pancreatectomies, 21 distal pancreatectomies, and 2 partial pancreatectomies) whereas 79 patients were found to be unresectable and underwent palliative bypass and/or biopsy. Median survival was 20.4 months for resectable patients versus 4.5 months for unresectable patients (P<0.001). Of the 129 resected patients, factors significantly (P<0.05) favoring long-term survival on univariate analysis included well-differentiated histology, common bile duct or ampullary adenocarcinoma, early stage, tumor diameter <2 cm, negative margins, and absence of lymph node metastases, perineural, or vascular invasion. Age, sex, race, and type of procedure had no influence on survival. On multivariate analysis, only tumor differentiation appeared independently related to survival. Using Kendalls tau analysis, tumor type and grade correlated significantly with all other predictors. CONCLUSIONS Of all variables studied, tumor type and poor tumor differentiation in periampullary neoplasms appear to be markers that predict a constellation of other adverse findings.
Archives of Surgery | 2010
Christian de Virgilio; Arezou Yaghoubian; Amy H. Kaji; J. Craig Collins; Karen E. Deveney; Matthew Dolich; David W. Easter; O. Joe Hines; Steven J. Katz; Terrence Liu; Ahmed Mahmoud; Marc L. Melcher; Steven N. Parks; Mark E. Reeves; Ali Salim; Lynette A. Scherer; Danny Takanishi; Kenneth Waxman
BACKGROUND We sought to determine whether US Medical Licensing Examination (USMLE) Step 1 score, American Board of Surgery (ABS) In-Training Examination (ABSITE) score, and other variables are associated with failing the ABS qualifying and certifying examinations. Identifying such factors may assist in the early implementation of an academic intervention for at-risk residents. DESIGN Retrospective review. SETTING Seventeen general surgery training programs in the western United States. PARTICIPANTS Six hundred seven residents who graduated in 2000-2007. MAIN OUTCOME MEASURES First-time pass rates on the qualifying and certifying examinations, US vs non-US medical school graduation, USMLE Steps 1 and 2 scores, ABSITE scores, operative case volume, fellowship training, residency program type, and mandatory research. RESULTS The first-time qualifying and certifying examination pass rates for the 607 graduating residents were 78% and 74%, respectively. On multivariable analysis, scoring below the 35th percentile on the ABSITE at any time during residency was associated with an increased risk of failing both examinations (odds ratio, 0.23 [95% confidence interval, 0.08-0.68] for the qualifying examination and 0.35 [0.20-0.61] for the certifying examination), as was scoring less than 200 on the USMLE Step 1 (0.36 [0.21-0.62] for the qualifying examination and 0.62 [0.42-0.93] for the certifying examination). A mandatory research year was associated with an increased likelihood of passing the certifying examination (odds ratio, 3.3 [95% confidence interval, 1.6-6.8]). CONCLUSIONS Residents who are more likely to fail the ABS qualifying and certifying examinations can be identified by a low USMLE Step 1 score and by poor performance on the ABSITE at any time during residency. These findings support the use of the USMLE Step 1 score in the surgical residency selection process and a formal academic intervention for residents who perform poorly on the ABSITE.
Journal of Vascular and Interventional Radiology | 2001
Steven C. Rose; Tarek Hassanein; David W. Easter; Reza Gamagami; Michael Bouvet; Dolores H. Pretorius; Thomas R. Nelson; Thomas B. Kinney; Gina James
PURPOSE To determine if three-dimensional ultrasound (3D US), by nature of its ability to simultaneously evaluate structures in three orthogonal planes and to study relationships of devices to tumor(s) and surrounding anatomic structures from any desired orientation, adds significant additional information to real-time 2D US used for placement of devices for ablation of focal liver tumors. MATERIALS AND METHODS Sixteen patients underwent focal ablation of 23 liver tumors during two intraoperative cryoablation (CA) procedures, three intraoperative radiofrequency ablation (RFA) procedures, 11 percutaneous ethanol injections (PEI) procedures, and six percutaneous RFA procedures. After satisfactory placement of the ablative device(s) with 2D US guidance, 3D US was used to reevaluate adequacy to device position. Information added by 3D US and resultant alterations in device deployment were tabulated. RESULTS 3D US added information in 20 of 22 (91%) procedures and caused the operator to readjust the number or position of ablative devices in 10 of 22 (45%) of procedures. Specifically, 3D US improved visualization and confident localization of devices in 13 of 22 (59%) procedures, detected unacceptable device placement in 10 of 22 (45%), and determined that 2D US had incorrectly predicted device orientation to a tumor in three of 22 (14%). CONCLUSIONS Compared to conventional 2D US, 3D US provides additional relationship information for improved placement and optimal distribution of ablative agents for treatment of focal liver malignancy.
Surgical Endoscopy and Other Interventional Techniques | 2008
Yoav Mintz; Santiago Horgan; Michelle K. Savu; John Cullen; Alana Chock; Sonia Ramamoorthy; David W. Easter; Mark A. Talamini
BackgroundThe indications for natural orifice translumenal surgery (NOTES) are yet to be determined. Morbidly obese patients may be one population that would benefit from this approach due to the elimination of wound complications and possibly a faster recovery. As a bariatric restrictive procedure, sleeve gastrectomy could be one indication for NOTES. To test the feasibility of this procedure with a NOTES approach, a pig model was used.MethodsAcute studies investigated five 40-kg farm pigs. The rectum was used as the port of entry to the peritoneal cavity, and the stomach was manipulated endoluminally using a gastroscope. Vision was acquired through a 5-mm laparoscope introduced transabdominally (i.e. via the hybrid technique). A 10-mm incision was made on the anterior wall of the rectum and dilated to accommodate a 12-mm trocar introduced through the rectal wall into the peritoneal cavity. The greater curvature of the stomach then was divided and detached, starting from the antrum and proceeding to the esophagogastric junction using a laparoscopic stapler. The sleeve gastrectomy was completed by dividing the short gastric vessels with an ultrasonic scalpel. The gastric pouch then was removed through the rectal incision.ResultsA NOTES gastric sleeve resection was successfully performed in all five pigs. The technique was developed, and feasibility was determined. After resection, the gastric remnant was inflated, with no evidence of leakage. At autopsy, intact suture lines were noted. Closure of the rectal incision was not attempted.ConclusionA NOTES sleeve gastrectomy is feasible in porcine animal models. The rectal port of entry allows rigid laparoscopic instruments to be introduced into the peritoneal cavity and enables performance of gastrointestinal procedures the same as in standard laparoscopic surgery. Extra-long instruments are necessary for dissection and division of the stomach at the esophagogastric junction and for accessing the short gastric vessels.
JAMA Surgery | 2013
Samuel I. Schwartz; Joseph M. Galante; Amy H. Kaji; Matthew Dolich; David W. Easter; Marc L. Melcher; Kevin Patel; Mark E. Reeves; Ali Salim; Anthony J. Senagore; Danny Takanishi; Christian de Virgilio
IMPORTANCE The 80-hour work-week limit for all residents was instituted in 2003 and studies looking at its effect have been mixed. Since the advent of the 16-hour mandate for postgraduate year 1 residents in July 2011, no data have been published regarding the effect of this additional work-hour restriction. OBJECTIVE To determine whether the 16-hour intern work limit, implemented in July 2011, has adversely affected operative experience. DESIGN, SETTING, AND PARTICIPANTS A retrospective review of categorical postgraduate year 1 Accreditation Council for Graduate Medical Education case logs from the intern class (N = 52) (with 16-hour work limit) compared with the 4 preceding years (2007-2010; N = 197) (without 16-hour work limit). A total of 249 categorical general surgery interns from 10 general surgery residency programs in the western United States were included. MAIN OUTCOMES AND MEASURES Total, major, first-assistant, and defined-category case totals. RESULTS As compared with the preceding 4 years, the 2011-2012 interns recorded a 25.8% decrease in total operative cases (65.9 vs 88.8, P = .005), a 31.8% decrease in major cases (54.9 vs 80.5, P < .001), and a 46.3% decrease in first-assistant cases (11.1 vs 20.7, P = .008). There were statistically significant decreases in cases within the defined categories of abdomen, endocrine, head and neck, basic laparoscopy, complex laparoscopy, pediatrics, thoracic, and soft tissue/breast surgery in the 16-hour shift intern era, whereas there was no decrease in trauma, vascular, alimentary, endoscopy, liver, and pancreas cases. CONCLUSIONS AND RELEVANCE The 16-hour work limit for interns, implemented in July 2011, is associated with a significant decrease in categorical intern operative experience. If the 16-hour shift were to be extended to all postgraduate year levels, one can anticipate that additional years of training will be needed to maintain the same operative volume.
Molecular Diagnosis | 1999
Linda Wasserman; Anna D. Dreilinger; David W. Easter; Anne M. Wallace
BACKGROUND Initial validation of a seminested reverse transcription-polymerase chain reaction (RT-PCR) assay for HER2/neu for use in detecting circulating tumor cells in the peripheral blood or bone marrow of breast cancer patients is described. RT-PCR assays for other epithelial markers, including the cytokeratins and carcinoembryonic antigen frequently lack specificity, sensitivity, or both. Thus, there is a need for an assay that is both sensitive and specific to be used to monitor breast cancer patients for micrometastatic or minimal residual disease. METHOD AND RESULTS Assay conditions were optimized using the MCF7 breast cancer cell line and the Raji B-cell lymphoma cell line. The assay can detect as little as 3 mg of MCF7 RNA within a background of 3 mg of Raji RNA. The assay was positive in 12 of 12 breast tumors. None of the 33 peripheral blood or stem cell samples form patients without evidence of breast cancer were positive. Peripheral blood from 17 breast cancer patients was collected immediately before surgery and evaluated. The assay was positive in five of six patients with Stage II, four of eight patients with Stage I and one of three patients with Stage 0 disease. CONCLUSIONS The seminested HER2/neu RT-PCR assay compares favorably with RT-PCR assays for other epithelial cell markers in terms of both sensitivity and specificity as a method to detect disseminated breast cancer cells. In breast cancer patients, the higher the disease stage, the more frequently was the assay positive.
Surgical Endoscopy and Other Interventional Techniques | 1996
S. Wise Unger; G. L. Glick; M. Landeros; John M. Cosgrove; Jeffrey Crooms; Dan Deziel; Moshe Dudai; David W. Easter; David Edelman; Robert J. Fitzgibbons; Ariel Halevy; Charles Haynie; John G. Hunter; Demetrius E. M. Litwin; Alex Nagy; Douglas O. Olsen; Edward Philips; Barry Salky; Bruce D. Schirmer; J. Stephen Scott; Carol Scott-Connor; Irwin Simon; Nathaniel J. Soper; Lee L. Swanstrom; William Traverso; Michael Woods
AbstractBackground: Cystic duct leak is a rare complication of laparoscopic surgery. To study the incidence, presentation, and management of cystic duct leak (CDL) after laparoscopic cholecystectomy (LC) a retrospective study of centers doing large numbers of LC was done. Methods: Patient information was obtained by a questionnaire sent to experienced laparoscopic surgeons. This queried demographic information, course of the original operation, presentation, diagnostic studies, and management of CDL after LC. Results: Some 22,165 LCs were performed by 24 surgeons; there were 58 cases of CDL (0.26%); 21% of the surgeons reported no CDLs; 60% of CDLs occurred in the first 25% of each surgeon’s experience, but CDLs continue to occur even in their most recent 10% of cases. Preoperative symptoms, prior surgery, and comorbid conditions did not predict CDL. Acute cholecystitis was present at initial surgery in 47%. Symptoms of CDL an average of 3.1 days post-LC were abdominal pain 78%, fever 26%, nausea 35%, vomiting 22%, abdominal distention 26%, and shoulder pain 12%. WBCs and LFTs were elevated in more than two-thirds of the cases. ERCP was most frequently used to diagnose CDL (53%) and was successful in 97%, although sonogram (40%) and HIDA scan (26%) and CT (26%) were also used. Management included ERCP and ductal decompression in 27 patients, percutaneous drainage in 13 patients, open laparotomy in 14, laparoscopy in three, and observation in two. Patients were discharged an average of 7.4 days post discovery of leak. Stents were removed an average of 30 days post ERCP. Ninety-four percent were complete cures. There was one post-treatment abscess. Two deaths due to multisystem failure unrelated to leak occurred. Conclusions: Cystic duct leak is rare and fairly easily diagnosed. It occurs more frequently during the learning curve, but also after much experience. ERCP and ductal decompression play a large role in treatment, but almost all standard methods of treatment yield successful outcomes with low morbidity.
Surgical Endoscopy and Other Interventional Techniques | 1995
David W. Easter; R. Jamshidipour; K. McQuaid
We report a case of metastatic lobular breast carcinoma with extrahepatic gastrointestinal disease. On the basis of clinical findings, radiologic investigations, computerized axial tomography, gastrointestinal endoscopy, and gastric biopsy, the diagnosis of gastric and ileal Crohns disease was made. The correct diagnosis of peritoneal carcinomatosis was made at laparoscopy. This case exemplifies the utility of laparoscopy in establishing the diagnosis and staging for abdominal disease of uncertain etiology.
Journal of Laparoendoscopic & Advanced Surgical Techniques | 2001
Bryan K. Chen; Reza Gamagami; Justin Kang; David W. Easter; Tony Lopez
We report a case of a large post-traumatic liver cyst in a symptomatic patient treated by laparoscopic excision in an ambulatory setting. This rare lesion can be treated safely by this alternative modality on an outpatient basis, with minimal morbidity.