9 results on '"Dana K. Andersen"'
Search Results
2. Abdominal CT predictors of fibrosis in patients with chronic pancreatitis undergoing surgery
- Author
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Atif Zaheer, Amitasha Sinha, Martin A. Makary, Siva P. Raman, Dana K. Andersen, Elham Afghani, Vikesh K. Singh, Elliot K. Fishman, Karen Matsukuma, Michael Cruise, and Sumera Ali
- Subjects
Adult ,Male ,Radiography, Abdominal ,medicine.medical_specialty ,Iohexol ,Contrast Media ,Young Adult ,Predictive Value of Tests ,Fibrosis ,Pancreatitis, Chronic ,Triiodobenzoic Acids ,Biopsy ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Pancreas ,Aged ,Pancreatic duct ,Pain, Postoperative ,medicine.diagnostic_test ,business.industry ,Pancreatic Ducts ,Reproducibility of Results ,Interventional radiology ,General Medicine ,Middle Aged ,medicine.disease ,Surgery ,Radiographic Image Enhancement ,medicine.anatomical_structure ,Predictive value of tests ,Pancreatitis ,Female ,Histopathology ,Radiology ,business ,Tomography, Spiral Computed ,Calcification - Abstract
To determine which abdominal CT findings predict severe fibrosis and post-operative pain relief in chronic pancreatitis (CP). Pre-operative abdominal CTs of 66 patients (mean age 52 ± 12 years, 53 % males) with painful CP who underwent the Whipple procedure (n = 32), Frey procedure (n = 32) or pancreatic head biopsy (n = 2), between 1/2003-3/2014, were evaluated. CT was evaluated for parenchymal calcifications, intraductal calculi, main pancreatic duct dilation (>5 mm), main pancreatic duct stricture, and abnormal side branch(es). The surgical histopathology was graded for fibrosis. CT findings were evaluated as predictors of severe fibrosis and post-operative pain relief using regression and area under receiver operating curve (AUC) analysis. Thirty-eight (58 %) patients had severe fibrosis. Parenchymal calcification(s) were an independent predictor of severe fibrosis (p = 0.03), and post-operative pain relief over a mean follow-up of 1-year (p = 0.04). Presence of >10 parenchymal calcifications had higher predictive accuracy for severe fibrosis than 1-10 parenchymal calcification(s) (AUC 0.88 vs. 0.59, p = 0.003). The predictive accuracy of >10 versus 1-10 parenchymal calcifications increased after adjusting for all other CT findings (AUC 0.89 vs. 0.63, p = 0.01). Parenchymal calcification(s) independently predict severe fibrosis and are significantly associated with post-operative pain relief in CP. The presence of >10 parenchymal calcifications is a better predictor of severe fibrosis than 1-10 parenchymal calcification(s). • Parenchymal calcifications in chronic pancreatitis independently predict post-operative pain relief • Intraductal calculi and MPD dilation are not associated with post-operative pain relief • Better patient selection for pancreatic resection surgery in painful chronic pancreatitis
- Published
- 2014
3. Warm-up on a simulator improves residents’ performance in laparoscopic surgery: a randomized trial
- Author
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Dana K. Andersen, Chi Chiung Grace Chen, Jorie M. Colbert-Getz, Kimberly Steele, Shari M. Lawson, Betty Chou, Isabel C. Green, and Andrew J. Satin
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Adult ,Male ,Laparoscopic surgery ,medicine.medical_specialty ,Randomization ,Warm-Up Exercise ,Sterilization, Tubal ,Ovariectomy ,Urology ,medicine.medical_treatment ,Outcome assessment ,Hysterectomy ,law.invention ,Gynecologic Surgical Procedures ,Randomized controlled trial ,law ,Outcome Assessment, Health Care ,medicine ,Humans ,Computer Simulation ,Global rating scale ,Simulation ,business.industry ,Internship and Residency ,Obstetrics and Gynecology ,Global Rating ,Treatment Outcome ,Preoperative Period ,Physical therapy ,Tubal surgery ,Female ,Laparoscopy ,Clinical Competence ,business - Abstract
Our aim was to assess the impact of immediate preoperative laparoscopic warm-up using a simulator on intraoperative laparoscopic performance by gynecologic residents. Eligible laparoscopic cases performed for benign, gynecologic indications were randomized to be performed with or without immediate preoperative warm-up. Residents randomized to warm-up performed a brief set of standardized exercises on a laparoscopic trainer immediately before surgery. Intraoperative performance was scored using previously validated global rating scales. Assessment was made immediately after surgery by attending faculty who were blinded to the warm-up randomization. We randomized 237 residents to 47 minor laparoscopic cases (adnexal/ tubal surgery) and 44 to major laparoscopic cases (hysterectomy). Overall, attendings rated upper-level resident performances (postgraduate year [PGY-3, 4]) significantly higher on global rating scales than lower-level resident performances (PGY-1, 2). Residents who performed warm-up exercises prior to surgery were rated significantly higher on all subscales within each global rating scale, irrespective of the difficulty of the surgery. Most residents felt that performing warm-up exercises helped their intraoperative performances. Performing a brief warm-up exercise before a major or minor laparoscopic procedure significantly improved the intraoperative performance of residents irrespective of the difficulty of the case.
- Published
- 2013
4. Advances in the Etiology and Management of Hyperinsulinemic Hypoglycemia After Roux-en-Y Gastric Bypass
- Author
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Yunfeng Cui, Dana K. Andersen, and Dariush Elahi
- Subjects
endocrine system ,medicine.medical_specialty ,Gastric Bypass ,Octreotide ,Incretin ,Nesidioblastosis ,Hypoglycemia ,medicine.disease_cause ,Hyperinsulinism ,Internal medicine ,Diabetes mellitus ,Weight Loss ,medicine ,Humans ,Obesity ,Hyperinsulinemic hypoglycemia ,business.industry ,Neuroglycopenia ,Gastroenterology ,nutritional and metabolic diseases ,Type 2 Diabetes Mellitus ,medicine.disease ,Endocrinology ,Diabetes Mellitus, Type 2 ,Surgery ,business ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Hyperinsulinemic hypoglycemia with severe neuroglycopenia has been identified as a late complication of Roux-en-Y gastric bypass (RYGB) in a small number of patients. The rapid resolution of type 2 diabetes mellitus after RYGB is probably related to increased secretion of the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), and patients with post-RYGB hypoglycemia demonstrate prolonged elevations of GIP and GLP-1 compared to non-hypoglycemic post-RYGB patients. Nesidioblastosis has been identified in some patients with post-RYGB hypoglycemia and is likely due to the trophic effects of GIP and GLP-1 on pancreatic islets. Treatment of hypoglycemia after RYGB should begin with strict dietary (low carbohydrate) alteration and may require a trial of diazoxide, octreotide, or calcium-channel antagonists, among other drugs. Surgical therapy should include consideration of a restrictive form of bariatric procedure, with or without reconstitution of gastrointestinal continuity. Partial or total pancreatic resection should be avoided.
- Published
- 2011
5. Analysis of errors in laparoscopic surgical procedures
- Author
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Richard M. Satava, Sanziana A. Roman, Neal E. Seymour, Michael K. O'Brien, Anthony G. Gallagher, and Dana K. Andersen
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medicine.medical_specialty ,medicine.medical_treatment ,MEDLINE ,Electrocoagulation ,medicine ,Humans ,Single-Blind Method ,Medical physics ,Intraoperative Complications ,Laparoscopy ,Retrospective Studies ,Observer Variation ,Surgical team ,Medical Errors ,medicine.diagnostic_test ,business.industry ,Dissection ,Internship and Residency ,Reproducibility of Results ,Videotape Recording ,Retrospective cohort study ,Surgery ,Endoscopy ,Inter-rater reliability ,Cholecystectomy, Laparoscopic ,Liver ,General Surgery ,Feasibility Studies ,Cholecystectomy ,Clinical Competence ,Burns ,business ,Abdominal surgery - Abstract
Background: The determination of laparoscopic surgeon ability is essential to training error avoidance. The present study describes a practical method of surgical error analysis. Methods: After review of practice videotapes of the excisional phase of laparoscopic cholecystectomy, consensus on the identification of eight errors was achieved. Interrater agreement at the end of this phase was 84–96%. Fourteen study videotapes of gallbladder excision were then observed independently by expert reviewers blinded to surgical team identity. Procedures were assessed using a scoring matrix of 1-min segments with each error reported each minute. Results: Interrater agreement was 84–100% for all error catagories. Conclusions: The present study demonstrates that excellent interrater agreement of procedural errors can be achieved by carefully defining and training recognition of targeted events. Extension of this simple and reliable analysis tool to other procedures should be feasible to define behaviors leading to adverse clinical outcomes.
- Published
- 2004
6. Pancreatic Resection: Effects on Glucose Metabolism
- Author
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Lori A. Slezak and Dana K. Andersen
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medicine.medical_specialty ,Pancreatic disease ,medicine.medical_treatment ,Pancreatic Polypeptide ,Gastroenterology ,Pancreaticoduodenectomy ,Whipple Procedure ,Pancreatectomy ,Insulin resistance ,Internal medicine ,Diabetes Mellitus ,medicine ,Humans ,Insulin ,Pancreatic polypeptide ,Pancreas ,business.industry ,Pancreatic Diseases ,Glucagon ,medicine.disease ,Glucagon Deficiency ,Surgery ,Glucose ,medicine.anatomical_structure ,business - Abstract
Pancreatic resection results in hormonal abnormalities that are dependent on the extent and location (proximal versus distal) of the resected portion of the gland. The form of glucose intolerance which results from pancreatic resection is termed pancreatogenic diabetes. It is associated with features distinct from both type I (insulin-dependent) and type II (insulin-independent, or adult-onset) diabetes. Hepatic insulin resistance with persistent endogenous glucose production and enhanced peripheral insulin sensitivity result in a brittle form of diabetes which can be difficult to manage. In addition to insulin deficiency, the endocrine abnormalities that accompany pancreatic resection can include glucagon deficiency or pancreatic polypeptide (PP) deficiency if the resection is distal or proximal, respectively. Glucagon deficiency can contribute to iatrogenic hypoglycemia, and PP deficiency can contribute to persistent hyperglycemia due to impaired hepatic insulin action. Pancreatic resections that spare the duodenum, such as distal pancreatectomy, duodenum-preserving pancreatic head resection (Beger procedure), or extended lateral pancreaticojejunostomy with excavation of the pancreatic head (Frey procedure), are associated with a lower incidence of new or worsened diabetes than the standard or pylorus-preserving pancreaticoduodenectomy (Whipple procedure) or total pancreatectomy. Operative considerations for the treatment of pancreatic disease should include strategies to minimize the hormonal impairment of pancreatic resection.
- Published
- 2001
7. Neural regulation of the endocrine pancreas
- Author
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Dana K. Andersen, David M. Shavelle, and F. Charles Brunicardi
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endocrine system ,geography ,medicine.medical_specialty ,geography.geographical_feature_category ,Gastroenterology ,Biology ,Neuroendocrinology ,Pancreatic Hormones ,Islet ,Glucagon ,Islets of Langerhans ,Endocrinology ,medicine.anatomical_structure ,Somatostatin ,Oncology ,Internal medicine ,medicine ,Animals ,Humans ,Pancreatic polypeptide ,Endocrine system ,Nervous System Physiological Phenomena ,Pancreas ,Hormone - Abstract
The endocrine pancreas is innervated by a rich neural supply that has a potent regulatory effect on islet hormone secretion. The innervation includes sympathetic, parasympathetic, sensory afferent, and peptidergic neurons, enteropancreatic neurons, and most recently nitric oxide synthase-containing neurons, all of which contribute to the overall regulation of the endocrine pancreas (Fig. 1). The mechanisms involving the innervation of the islet have been studied extensively in animal models with fewer studies reported on the neural regulation of the human islet. The purpose of this article is to summarize what is presently known about the innervation of the endocrine pancreas, including animal and human studies, and neural regulation of islet hormone secretion.
- Published
- 1995
8. Insulin's effect on bile flow and lipid excretion during euglycemia and hypoglycemia
- Author
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Dana K. Andersen, R. Scott Jones, John B. Hanks, WS Putnam, and Harold E. Lebovitz
- Subjects
Blood Glucose ,Cholagogues and Choleretics ,medicine.medical_specialty ,Choleretic ,Physiology ,medicine.medical_treatment ,Hypoglycemia ,Glucagon ,Dogs ,Internal medicine ,medicine ,Animals ,Bile ,Insulin ,Phospholipids ,Pancreatic duct ,Common bile duct ,business.industry ,Gastroenterology ,medicine.disease ,Lipids ,Cholesterol ,medicine.anatomical_structure ,Endocrinology ,Duodenum ,Cholecystectomy ,business - Abstract
Mongrel dogs were prepared by cholecystectomy, ligation of the lesser pancreatic duct, and insertion of modified Thomas cannulas into the stomach and duodenum. When the dogs had recovered from surgery, studies were performed on them, conscious and unanesthetized after an overnight fast. The common bile duct was catheterized through the opened duodenal cannula for collection of hepatic bile. Bile flow was stabilized by the intravenous infusion of sodium taurocholate. After 2 hr of taurocholate infusion, insulin was added to the infusion and continued for the duration of the experiment. Glucose was administered intravenously during the first 120 min of insulin administration to maintain euglycemia; then the glucose was discontinued. The intravenous infusion of insulin during euglycemia maintained by glucose infusion caused a significant increase in bile flow and a decrease in bile salt concentration, but no change in bile salt output. There was a decrease in cholesterol concentration and output and in phospholipid concentration, but no significant change in phospholipid output. When glucose infusion was discontinued and hypoglycemia occurred, there was a further significant increase in bile flow, but no other change. These studies demonstrate that the choleretic action of insulin is not dependent upon hypoglycemia and that intravenously administered insulin may cause increased bile secretion without increase in serum glucagon concentration. These experiments also confirm that insulin choleresis may be associated with a decline in cholesterol output.
- Published
- 1984
9. Invited commentary
- Author
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Dana K. Andersen
- Subjects
Surgery - Published
- 1988
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