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Dive into the research topics where Greg V. Stiegmann is active.

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Featured researches published by Greg V. Stiegmann.


The New England Journal of Medicine | 1992

Endoscopic sclerotherapy as compared with endoscopic ligation for bleeding esophageal varices

Greg V. Stiegmann; John S. Goff; Patrice A. Michaletz-Onody; Jacob Korula; David A. Lieberman; Zahid A. Saeed; R. Matthew Reveille; John H. Sun; Steven R. Lowenstein

Abstract Background. Endoscopic sclerotherapy is an accepted treatment for bleeding esophageal varices, but it is associated with substantial local and systemic complications. Endoscopic ligation, a new form of endoscopic treatment for bleeding varices, may be safer. We compared the effectiveness and safety of the two techniques. Methods. In this randomized trial we compared endoscopic sclerotherapy and endoscopic ligation in 129 patients with cirrhosis who had proved bleeding from esophageal varices. Sixty-five patients were treated with sclerotherapy, and 64 with ligation. Initial treatment for acute bleeding was followed by elective retreatment to eradicate varices. The patients were followed for a mean of 10 months, during which we determined the incidence of complications and recurrences of bleeding, the number of treatments needed to eradicate varices, and survival. Results. Active bleeding at the first treatment was controlled by sclerotherapy in 10 of 13 patients (77 percent) and by ligation in 12...


Annals of Surgery | 1981

Acute bleeding varices: a five-year prospective evaluation of tamponade and sclerotherapy.

J. Terblanche; Hamid I. Yakoob; Philip C. Bornman; Greg V. Stiegmann; Roy Bane; Mike Jonker; Wright Jp; Ralph E. Kirsch

In a five-year study of massive upper gastrointestinal hemorrhage, 143 patients had esophageal variaes diagnosed on emergency endoscopic examination. Seventy-one patients had active bleeding from varices and required Sengstaken tube tamponade during at least one hospital admission. The remaining patients included 33 with varietal bleeding which had stopped and 39 who were bleeding from another source. Sixty-six of the former group of 71 patients were referred for emergency injection sclerotherapy. These 66 patients were followed prospectively to August 1980, and had 137 episodes of enduscopically proven variceal bleeding requiring Seng-staken tube control followed by injection sclerotherapy during 93 separate hospital admissions. Definitive control of hemorrhage was achieved in 95% the patients admitted to the hospital (single injection 70%; two or three injections 22%). The death rate per hospital admission was 28%. No patient died of continued variceal bleeding, and exsanguinating variceal hemorrhage no longer poses a major problem at our hospital. The cumbiued use of initial Sengstaken tube tamponade followed by injection sclerotherapy has simplified emergency treatment in the group of patients who continue to bleed actively from esophageal varices, despite initial conservative treatment


Annals of Surgery | 2013

Slower walking speed forecasts increased postoperative morbidity and 1-year mortality across surgical specialties.

Thomas N. Robinson; Daniel S. Wu; Angela Sauaia; Christina L. Dunn; Jennifer E. Stevens-Lapsley; Marc Moss; Greg V. Stiegmann; Csaba Gajdos; Joseph C. Cleveland; Sharon K. Inouye

Objective: The purpose of this study was to determine the relationship between the Timed Up and Go test and postoperative morbidity and 1-year mortality, and to compare the Timed Up and Go to the standard-of-care surgical risk calculators for prediction of postoperative complications. Methods: In this prospective cohort study, patients 65 years and older undergoing elective colorectal and cardiac operations with a minimum of 1-year follow-up were included. The Timed Up and Go test was performed preoperatively. This timed test starts with the subject standing from a chair, walking 10 feet, returning to the chair, and ends after the subject sits. Timed Up and Go results were grouped as fast ⩽ 10 seconds, intermediate = 11–14 seconds, and slow ≥ 15 seconds. Receiver operating characteristic curves were used to compare the 3 Timed Up and Go groups to current standard-of-care surgical risk calculators at forecasting postoperative complications. Results: This study included 272 subjects (mean age of 74 ± 6 years). Slower Timed Up and Go was associated with increased postoperative complications after colorectal (fast 13%, intermediate 29%, and slow 77%; P < 0.001) and cardiac (fast 11%, intermediate 26%, and slow 52%; P < 0.001) operations. Slower Timed Up and Go was associated with increased 1-year mortality following both colorectal (fast 3%, intermediate 10%, and slow 31%; P = 0.006) and cardiac (fast 2%, intermediate 3%, and slow 12%; P = 0.039) operations. Receiver operating characteristic area under curve of the Timed Up and Go and the risk calculators for the colorectal group was 0.775 (95% CI: 0.670–0.880) and 0.554 (95% CI: 0.499–0.609), and for the cardiac group was 0.684 (95% CI: 0.603–0.766) and 0.552 (95% CI: 0.477–0.626). Conclusions: Slower Timed Up and Go forecasted increased postoperative complications and 1-year mortality across surgical specialties. Regardless of operation performed, the Timed Up and Go compared favorably to the more complex risk calculators at forecasting postoperative complications.


American Journal of Clinical Oncology | 2009

Results of a Phase I Trial of 12 Patients With Locally Advanced Pancreatic Carcinoma Combining Gefitinib, Paclitaxel, and 3-dimensional Conformal Radiation: Report of Toxicity and Evaluation of Circulating k-ras as a Potential Biomarker of Response to Therapy

Christine Olsen; Tracey E. Schefter; Honglin Chen; Madeleine A. Kane; Stephen Leong; Martin D. McCarter; Yang Chen; Philip C. Mack; S. Gail Eckhardt; Greg V. Stiegmann; David Raben

Objective:To evaluate the toxicity of daily gefitinib, an epidermal growth factor receptor-tyrosine kinase inhibitor, with concurrent chemoradiation (CRT) in patients with locally advanced pancreatic adenocarcinoma and prospectively evaluate plasma k-ras as a potential marker of response to gefitinib and CRT. Methods:Eleven of 12 eligible patients enrolled received a 7-day induction of gefitinib (250 mg PO) followed by daily gefitinib with concurrent CRT. Patients received 50.4 Gy/28 fractions of external beam radiation with weekly paclitaxel (40 mg/m2 IV) followed by maintenance on gefitinib. Plasma k-ras codon 12 mutations were detected using a two-stage restriction fragment length polymorphism-polymerase chain reaction assay on patients’ plasma both before and after therapy. Mutations were confirmed by direct sequencing. Results:Common adverse events included grade 1 skin rash (63%), grade 1 to 2 gastrointestinal symptoms including anorexia, nausea, vomiting, and diarrhea occurred in 63% of patients, grade 3 nausea occurred in 45% of patients. Three patients did not complete therapy, only one was possibly associated with study drug. K-ras mutations were detected in the pre-gefitinib plasma of 5/11 patients and in the matched tumor tissue of 3/4 patients. In patients where k-ras mutations were undetectable post-treatment, survival times were favorable. Conclusions:Combination of daily gefitinib with concurrent CRT in this locally advanced pancreatic cancer population was reasonably tolerated. Rapid changes in serum k-ras may provide critical information as to the efficacy of a novel agent and assist in tailoring treatment for cancers of the pancreas.


Annals of Surgery | 2012

Antenna coupling--a novel mechanism of radiofrequency electrosurgery complication: practical implications.

Thomas N. Robinson; Kelli S. Barnes; Henry R. Govekar; Greg V. Stiegmann; Christina L. Dunn; Francis T. McGreevy

Objectives:(1) To determine if antenna coupling occurs in common operating room scenarios. (2) To define modifiable clinical variables that reduce the magnitude of antenna coupling. Background:Mechanisms of electrosurgical burns where monitoring devices contact the surgical patient are unclear. Antenna coupling occurs when the “bovie” active electrode (electrically active transmitting antenna) emits energy, which is captured by a nonelectrically active wire (electrically inactive receiving antenna) in close proximity without direct contact. Methods:Monopolar radiofrequency energy was delivered to a laparoscopic instrument (electrically active transmitting antenna), whereas other nonelectrically active wires (electrically inactive receiving antenna) including electrocardiogram (EKG) lead, nonactive “bovie” pencil, and nerve electrode monitor were placed in proximity. Temperature changes of tissue placed adjacent to the electrically inactive receiving antennae were measured. Results:Nonelectrically active wires (receiving antenna) increase tissue temperature when lying parallel to the active electrode cord: EKG pad 2.4°C ± 1.2°C (P = 0.002), “bovie” pencil tip 90°C ± 9°C (P < 0.001), and nerve electrode monitor 106°C ± 12°C (P < 0.001). Factors that reduced the heat generated by antenna coupling included the following: increasing angulation between transmitting and receiving antennae (parallel = 90°C ± 9°C; 45° angle = 53°C ± 10°C; perpendicular = 35°C ± 11°C; P < .001), increasing separation distance between parallel transmitting and receiving antenna (<1 cm = 90°C ± 9°C; 15 cm = 44°C ± 18°C; 30 cm = 39°C ± 2°C; P < .001); and decreasing generator power setting (15 W = 59°C ± 11°C; 30 W = 90°C ± 9°C; 45 W = 98°C ± 8°C; P < .001). Conclusions:Antenna coupling occurs in common operating room scenarios. Simple, practical measures by the surgeon, such as orienting the receiving antenna at a greater angle and with greater separation to the active electrode cord, or lowering the generator power setting reduce antenna coupling.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2010

Surgeon-controlled factors that reduce monopolar electrosurgery capacitive coupling during laparoscopy.

Thomas N. Robinson; Katherine R. Pavlovsky; Heidi Looney; Greg V. Stiegmann; Francis T. McGreevy

Purpose To determine the factors that can be modified by the surgeon to reduce monopolar electrosurgery capacitive coupling during laparoscopy. Specific aims were to determine the capacitive coupling energy using different generator power settings, mode settings (cut vs. coagulation), and surgical techniques (desiccation vs. fulguration vs. open air activation). Methods An oscilloscope determined the cumulative energy (Joules) of capacitive coupling occurring using laparoscopic monopolar electrosurgery ex vivo. Results Higher power settings increased capacitive coupling energy (Joules): 25 Watts (1.1±0.7) versus 50 Watts (2.4±0.5; P<0.05). Coagulation mode created greater capacitive coupling energy (2.2±1.0) in comparison with cut mode (1.1±0.5; P<0.05). Open air activation (3.3±0.6) and fulguration (3.3±1.0) had higher capacitive coupling energy in comparison with desiccation (0.6±0.2; P<0.05). Conclusions Surgeons can minimize capacitive coupling energy during laparoscopy by lowering the power setting, using cut mode (instead of coagulation), and using the surgical technique of desiccation (instead of open air activation or fulguration).


Journal of Gastroenterology and Hepatology | 2004

Diagnosis and management of ectopic varices

Greg V. Stiegmann

Abstract  Ectopic varices are dilated portosystemic venous collateral vessels that may occur anywhere in the gastrointestinal tract. Ectopic varices account for approximately 5% of all hemorrhages from varices. Ectopic varices may occur as a result of portal hypertension from any cause but are more common (particularly duodenal and biliary varices) in patients with extrahepatic portal vein thrombosis. Ectopic varices may also develop following successful endoscopic obliteration of gastroesophageal varices. With the exception of isolated gastric fundal varices, ectopic varices have relatively low risk for bleeding. Diagnosis is often made by endoscopy; however, computed tomography, magnetic resonance imaging and portal venography may be needed in some cases. Endoscopic treatment is successful in many cases and is the safest option provided bleeding is definitively controlled. Surgical options are now reserved for treatment of life‐threatening bleeding or for shunt insertion in patients who are not candidates for transjugular intrahepatic portosystemic shunt (TIPS) as a result of portal vein thrombosis. Portal decompression using TIPS, in spite of the risk for encephalopathy, is the treatment of choice for bleeding from ectopic varices that cannot be successfully managed endoscopically.


Journal of Surgical Research | 2015

Postoperative pneumoperitoneum: is it normal or pathologic?

Brandon C. Chapman; Kelsey E. McIntosh; Edward L. Jones; Daniel Wells; Greg V. Stiegmann; Thomas N. Robinson

BACKGROUND Pneumoperitoneum on computed tomography (CT) after abdominal surgery is common, but its incidence, duration, and clinical significance is widely debated. MATERIALS AND METHODS A retrospective, cohort study of patients who underwent abdominal CT within 30 days of abdominal surgery. RESULTS Among 344 patients, pneumoperitoneum was found in 39% (135/344) of patients on postoperative days 0-6 in 53%, 7-13 in 41%, 14-20 in 23%, 21-27 in 13%, and 28-30 in 0%. Pneumoperitoneum was associated with the presence of a drain (P = 0.014) but not with age, gender, body mass index, smoking history, lung disease, or open versus laparoscopic surgery (P > 0.05 for all variables). Eight patients required intervention (6%), most commonly for anastomotic leak (4 patients, 50%). CONCLUSIONS Postoperative pneumoperitoneum on abdominal CT can be seen in up to 23% of patients 3-weeks postoperatively; however, only 6% of the patients required intervention emphasizing the typically benign consequences of postoperative free air.


Journal of Surgical Oncology | 2017

Impact of neoadjuvant chemoradiation on perioperative outcomes in patients with rectal cancer

Brandon C. Chapman; Patrick Hosokawa; William G. Henderson; Alessandro Paniccia; Douglas M. Overbey; Wells A. Messersmith; Christopher Hanyoung Lieu; Greg V. Stiegmann; Richard D. Schulick; Csaba Gajdos

Neoadjuvant chemoradiation for rectal cancer is associated with lower local recurrence rates. The objective of this study is to assess the impact of neoadjuvant therapy on perioperative complications in patients with rectal cancer.


Archives of Surgery | 1987

General Surgery Therapy Update Service

Greg V. Stiegmann

General Surgery Therapy Update Service is a loose-leaf compendium that covers the broad field of general surgery in 15 sections. The work is updated (

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Thomas N. Robinson

University of Colorado Denver

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Edward L. Jones

University of Colorado Denver

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Christina L. Dunn

University of Colorado Denver

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Henry R. Govekar

University of Colorado Denver

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Alessandro Paniccia

University of Colorado Denver

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Brandon C. Chapman

University of Colorado Denver

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Paul N. Montero

University of Colorado Denver

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Douglas M. Overbey

University of Colorado Denver

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Nicole T. Townsend

University of Colorado Denver

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Csaba Gajdos

University of Colorado Denver

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