Shishir K. Maithel

Construct and face validity of MIST-VR, Endotower, and CELTS Are we ready for skills assessment using simulators?

BackgroundVideo trainers may best offer visually realistic laparoscopic simulation, whereas virtual reality (VR) modules may best provide multidimensional objective measures of performance. This study compares the construct and face validity of three different laparoscopic simulators.MethodsSubjects were voluntarily enrolled at the Learning Center during the 2004 SAGES annual meeting. Each subject completed two repetitions of a single task on each of three simulators, MIST-VR, Endotower, and CELTS; performance scores were automatically generated and recorded. Scores of individuals with various levels of experience were compared to determine construct validity for each simulator. Experience was defined according to four parameters: (a) PGY level, (b) fellowship training, (c) basic laparoscopic cases, and (d) advanced laparoscopic cases. Subjects rated each simulator regarding six face validity (realism of simulation) parameters using a 10-point Likert scale (10 = best rating) and participant scores were compared to previously established expert scores (proficiency goals for training).ResultsNinety-one attendees completed the study. Construct validity was demonstrated for all three simulators; significant differences in scores were detected according to one parameter for MIST-VR, two parameters for Endotower, and all four parameters for CELTS. Face validity was rated as good to excellent for all three simulators (7.0 ± 0.3 for MIST-VR, 7.9 ± 0.3 for Endotower [p < 0.001 vs MIST-VR], and 8.7 ± 0.1 for CELTS [p = 0.001 vs MIST-VR, p = 0.01 vs Endotower]); 6%, 0%, and 36% of “expert” participants obtained expert scores on MIST-VR, Endotower, and CELTS, respectively.ConclusionsAll three simulators demonstrated significant construct and reasonable face validity. Although virtual reality holds great promise to expand the scope of laparoscopic simulation, current interfaces may limit their utility for assessment. Computer-enhanced video trainers may offer an improved interface while incorporating useful multidimensional metrics. Further work is needed to establish standards for appropriate skills assessment methods and performance levels using simulators.

Postoperative pancreatic fistulas are not equivalent after proximal, distal, and central pancreatectomy.

It is uncertain whether postoperative pancreatic fistulas after distal and central pancreatectomies behave similarly to those after pancreaticoduodenectomy. To date, this concept has not been validated either clinically or economically. Overall, 256 consecutive pancreatic resections from October 2001 to February 2006 (184 pancreaticoduodenectomies, 66 distal pancreatectomies, and 6 central pancreatectomies) were evaluated according to the International Study Group of Pancreatic Fistula classification scheme. Pancreatic fistula was defined as any measurable drainage on or after postoperative day 3, with amylase content greater than three times the normal serum value. Outcomes were divided into four grades: (1) no fistula, (2) grade A: biochemical fistula without clinical sequelae, (3) grade B: fistula requiring any therapeutic intervention, or (4) grade C: fistula with severe clinical sequelae. Grades B and C are considered clinically relevant fistulas based on worsening morbidity, increased length of stay, frequent hospital readmission, and increased costs/resource utilization. Clinical and economic outcomes were compared—grade for grade—across the three resection types. Fistulas of any extent (Grades A-C) occurred in one third of all patients; two thirds had no fistula. Overall, there were 16 readmissions (6%), six re-operations (2%), and no deaths attributable to pancreatic fistula. Outcomes between no fistula and grade A patients were identical across resection types, though grade A fistula was more common in distal pancreatectomy. For each resection type, length of stay and costs progressively increased with grades B and C. However, the negative impact of these clinically relevant fistulas varied between resection types. Rates for intensive care unit admission and rehabilitation placement were higher among pancreaticoduodenectomy patients. Total parenteral nutrition and antibiotic use were similar, but percutaneous drainage was used more often for distal pancreatectomy. Grade B fistula was more severe after distal pancreatectomy, as indicated by increased length of stay, readmissions, and total cost. Although reoperation rates for grade C fistulas were equivalent, intervals to reoperation were substantially longer after distal and central pancreatectomies. When classified according to International Study Group of Pancreatic Fistula criteria, clinically relevant pancreatic fistulas behaved differently depending on type of pancreatectomy. This translates into variable severity that guides management decisions, which ultimately dictate clinical outcomes and economic impact.

Epidural Analgesia for Pancreatoduodenectomy: A Critical Appraisal

IntroductionEpidural analgesia has emerged as a commonly applied method to improve pain management and reduce perioperative complications in major abdominal surgery. However, there is no detailed analysis of its efficacy for pancreatic operations. This study compares clinical and economic outcomes after epidural and intravenous analgesia for pancreatoduodenectomy.Material and methodsData for 233 consecutive patients, who underwent pancreatoduodenectomy, were prospectively acquired and retrospectively reviewed at a single institution, pancreato-biliary specialty practice. From October 2001 to February 2007, all patients were offered thoracic epidural analgesia, and those who declined received intravenous analgesia. Perioperative pain management was dictated as an element of a standardized clinical pathway for pancreatic resections. Clinical and economic outcomes were analyzed and compared for epidural analgesia and intravenous analgesia groups.ResultsOne hundred eighty-five patients received epidural analgesia, and 48 received intravenous analgesia, with equivalent baseline patient demographics between the groups. Patients administered epidural analgesia had lower pain scores but significantly higher rates of major complications. Pancreatic fistulae and postoperative ileus occurred more frequently, and patients with epidural analgesia more often required discharge to rehabilitation facilities. A trend towards longer hospitalizations was observed among epidural analgesia patients, but total costs were statistically equivalent between the groups. Further analysis demonstrates that 31% of epidural infusions were aborted before anticipated (fourth postoperative day) because of hemodynamic compromise and/or inadequate analgesia. These select patients required more transfusions, aggressive fluid resuscitation, and subsequently suffered even higher rates of gastrointestinal and respiratory complications, all attributing to higher costs. Multivariate analysis demonstrates that preoperative hematocrit concentration less than 36%, elderly age (>75xa0years), and chronic pancreatitis predict failure of epidural infusions.ConclusionThoracic epidural analgesia after pancreatic resections is associated with hemodynamic instability, which may compromise enteric anastomoses, gastrointestinal recovery, and respiratory function. These outcomes are exacerbated in poorly functioning epidurals and suggest that epidural analgesia may not be the optimal method for perioperative pain control when pancreatoduodenectomy is performed.

Impact of Regional Lymph Node Evaluation in Staging Patients With Periampullary Tumors

BackgroundTwo distinct lymph nodes reproducibly assessed by computed tomography for the evaluation of periampullary tumors are the common bile duct (CBD) node and the gastroduodenal artery (GDA) node. We examined whether radiographical enlargement of either lymph node predicts tumor resectability, nodal metastasis, or patient survival.MethodsNinety-four consecutive patients underwent attempted curative resection of periampullary tumors between September 2001 and June 2003. A single radiologist recorded in a retrospective, blinded fashion the short- and long-axis measurements of the CBD and GDA nodes.ResultsSixty-one percent (n = 57) of tumors were resectable by pancreaticoduodenectomy. Overall, actual 6-, 12-, and 18-month survival was 87%, 68%, and 63%, respectively. Enlarged radiographical nodal size by either axis was not associated with the presence of metastasis to these lymph nodes or with reduced overall patient survival. Only a CBD node short-axis size >10 mm predicted unresectability (odds ratio, 3.2; P = .036). Liver metastasis and/or carcinomatosis were present in 43% of unresectable patients, and this was associated with decreased survival at both 1 year (25% vs. 77%; P < .001) and 18 months (19% vs. 72%; P <.001). A pathologic diagnosis of metastasis to the GDA node, but not the CBD node, was associated with a similarly decreased survival (1 year: 33% vs. 78%, P = .028; 18 months: 22% vs. 70%, P = .023).ConclusionsFor presumed periampullary malignancy, a CBD node short-axis size >10 mm predicts tumor unresectability. Metastatic disease to the GDA node, particularly for pancreatic adenocarcinoma, portends a poor prognosis equivalent to that of hepatic or peritoneal spread. Given these findings, radiographical CBD lymph node measurements may guide selection for performing laparoscopic staging with or without ultrasonography in conjunction with GDA nodal biopsy in patients with periampullary malignancy.

Controversy about COOPERATE ABPM Trial Data

mm Hg, 63% between 120 and 150 mm Hg, and the remaining 19% more than 150 mm Hg. A similar incidence was observed among treatment groups. Interestingly, the high variability of the systolic BP values was more characteristic among patients who were able to effectively restrict their salt intake. As compared with the systolic values, the nighttime values were constant throughout the measurements, partly because the drugs were taken at night or bedtime. Naoyuki Nakao, MD, PhD Division of Nephrology Rokko Island Hospital Koh-Yoh Cho Naka 2-11 Higashinada, Kobe, Japan

Creatinine Clearance but Not Serum Creatinine Alone Predicts Long-Term Postoperative Survival after Lower Extremity Revascularization

Background: Renal insufficiency is a well-described risk factor for perioperative morbidity and shortened survival after major vascular procedures. Due to the potential inaccuracy of serum creatinine levels alone in measuring kidney function, our aim was to determine whether estimated creatinine clearance more consistently predicted long-term survival. Methods: A retrospective review of one institution’s vascular registry was performed. Logistic regression analysis was conducted to determine independent predictors of 1-, 2- and 3-year postoperative mortality. Creatinine clearance was estimated as [140 – age (years)] × weight (kg)/72 × serum creatinine (mg/dl), multiplied by 0.85 for women. Results: A total of 252 consecutive patients underwent infrainguinal bypass procedures between August 1999 and May 2000. Demographics included average age 68 years, 65% male, 74% diabetic, 12% dialysis-dependent, 23% history of congestive heart failure, 12% history of stroke and 20% serum creatinine >2 mg/dl. One-year mortality was 16% (n = 40), 2-year mortality was 25% (n = 64), and 3-year mortality was 35% (n = 88). There was no difference in serum creatinine values between survivors and non-survivors at 1 year (1.8 vs. 1.9, p = 0.80), 2 years (1.8 vs. 2.0, p = 0.62) or 3 years (1.8 vs. 2.0, p = 0.24), and creatinine >2 mg/dl did not predict long-term adverse outcomes. In contrast, reduced creatinine clearance (≤60 ml/min) was an independent predictor of mortality regardless of dialysis status (1 year: OR = 2.53, p = 0.014; 2 years: OR = 2.46, p = 0.004; 3 years: OR = 2.45, p = 0.001), and creatinine clearance was higher for survivors versus non-survivors at all 3 time points (1 year: 70.2 vs. 49.5, p = 0.003; 2 years: 72.3 vs. 51.2, p < 0.0001; 3 years: 74.7 vs. 52.6, p < 0.0001). Other independent predictors of mortality included a history of stroke (1 year: OR = 3.28, p = 0.008; 2 years: OR = 2.55, p = 0.025; 3 years: OR = 2.35, p = 0.038) and congestive heart failure (1 year: OR = 2.86, p = 0.006; 2 years: OR = 2.54, p = 0.005; 3 years: OR = 2.13, p = 0.017). Conclusions: Independent of dialysis status, a decreased creatinine clearance, but not elevated serum creatinine alone, is an independent predictor of mortality after lower extremity arterial reconstruction. Determination of creatinine clearance should replace serum creatinine in the preoperative risk evaluations of patients undergoing major vascular surgical procedures.

Consultants for the American Journal of Nephrology 2006

Kevin Abbott Christina Abrass Rajiv Agarwal Farah Ali Efthyvoulos Anastassiades Gema Ariceta Akhtar Ashfaq John Asplin Phyllis August Susan Bagby Asad Bakir George Bakris Vinod Bansal Amelia Bartholomew Amy Barton Pai David Basile Enrico Benedetti Angelito Bernardo Rajendra Bhimma Peter Blake Amy Bobrowski Michael Braun Carolyn Brecklin Ursula Brewster Ellen Brooks Nigel Brunskill Vito Campese Huseyin Celiker Michael Choi Giorgio Coen Richard Cohn Jay Cohn Terezila Coimbra James Cook Scott Cotler Mario Cozzolino Stanislaw Czekalski Mohamed Daha Farhard Danesh Robert Danziger Jie Ding