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Dive into the research topics where Brent W. Miedema is active.

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Featured researches published by Brent W. Miedema.


Journal of The American College of Surgeons | 2008

Use of Endoscopic Stents to Treat Anastomotic Complications after Bariatric Surgery

Steve Eubanks; Christopher A. Edwards; Nicole Fearing; Archana Ramaswamy; Roger de la Torre; Klaus Thaler; Brent W. Miedema; James S. Scott

BACKGROUND Complications after bariatric surgery often require longterm parenteral nutrition to achieve healing. Recently, endoscopic treatments have become available that provide healing while allowing for oral nutrition. The purpose of this study was to present outcomes of the largest series to date treating staple line complications after bariatric surgery with endoscopic covered stents. STUDY DESIGN A retrospective evaluation was performed of all patients treated for staple line complications after bariatric surgery at a single tertiary care bariatric center. Acute postoperative leaks, chronic gastrocutaneous fistulas, and anastomotic strictures refractory to endoscopic dilation after both gastric bypass and sleeve gastrectomy were included. RESULTS From January 2006 to June 2007, 19 patients (11 with acute leaks, 2 with chronic fistulas, and 6 with strictures) were treated with a total of 34 endoscopic silicone covered stents (23 polyester, 11 metal). Mean followup was 3.6 months. Immediate symptomatic improvement occurred in 90% (91% of acute leaks, 100% of fistulas, and 84% of strictures). Oral feeding was started in 79% of patients immediately after stenting. Resolution of leak or stricture after stent treatment occurred in 16 of 19 patients (84%). Healing of leak, fistula, and stricture occurred at means of 33 days, 46 days, and 7 days, respectively. Three patients (1 with leak, 1 with fistula, and 1 with stricture) had unsuccessful stent treatment. Migration of the stent occurred in 58% of 34 stents placed. Most migration was minimal, but three stents were removed surgically after distal small bowel migration. There was no mortality. CONCLUSIONS Treatment of anastomotic complications after bariatric surgery with endoscopic covered stents allows rapid healing while simultaneously allowing for oral nutrition. The primary morbidity is stent migration.


Journal of The American College of Surgeons | 2009

Single-Incision Laparoscopic Cholecystectomy Using Conventional Instruments: Early Experience in Comparison with the Gold Standard

Scott Reynold Philipp; Brent W. Miedema; Klaus Thaler

BACKGROUND The aim of this pilot study was to describe our initial experience with single-incision laparoscopic cholecystectomy (SILC) using conventional laparoscopic equipment in comparison with concurrent patients undergoing conventional multiincision laparoscopic cholecystectomy. STUDY DESIGN During the 7-month study period, data from all consecutive patients undergoing SILC by two surgeons were retrospectively analyzed and compared with data from patients undergoing conventional laparoscopic cholecystectomy by the same surgeons during the same time period. Outcomes measures included completion rate of attempted SILC, operative time, length of hospital stay, postoperative pain, and assessment of complications. RESULTS From 51 laparoscopic cholecystectomies performed during the study period, 29 were attempted using single-incision technique and 22 were performed using the conventional four incisions. Of the attempted SILC cases, 14 (48%) were successfully completed, with the remainder requiring one to three additional skin incisions. There were no conversions to open in either group. Operative time was significantly longer in SILC cases compared with conventional laparoscopic cholecystectomy (85 versus 67 minutes; p = 0.01). There was a tendency toward greater postoperative pain in the SILC group. No substantial difference in complications was identified. CONCLUSIONS SILC using conventional laparoscopic instrumentation is an effective alternative to standard four-incision laparoscopic cholecystectomy in selected patients. Development of a standardized technique and additional experience is needed for more consistent success. Additional studies of SILC are needed to demonstrate safety, define selection criteria, and determine any benefits over conventional laparoscopic cholecystectomy.


Lancet Oncology | 2003

Methods for decreasing postoperative gut dysmotility

Brent W. Miedema; Joel O. Johnson

Postoperative disturbances of gastrointestinal function (postoperative ileus) are among the most significant side-effects of abdominal surgery for cancer. Without specific treatment, major abdominal surgery causes a predictable gastrointestinal dysfunction which endures for 4-5 days and results in an average hospital stay of 7-8 days. Ileus occurs because of initially absent and subsequently abnormal motor function of the stomach, small bowel, and colon. This disruption results in delayed transit of gastrointestinal content, intolerance of food, and gas retention. The aetiology of ileus is multifactorial, and includes autonomic neural dysfunction, inflammatory mediators, narcotics, gastrointestinal hormone disruptions, and anaesthetics. In the past, treatment has consisted of nasogastric suction, intravenous fluids, correction of electrolyte abnormalities, and observation. Currently, the most effective treatment is a multimodal approach. Median stays of 2-3 days after removal of all or part of the colon (colectomy) are now achievable. Recent discoveries have the potential to significantly reduce postoperative ileus in patients with cancer who have had abdominal surgery.


Annals of Surgery | 2004

Sentinel Node Staging of Resectable Colon Cancer: Results of a Multicenter Study

Monica M. Bertagnolli; Brent W. Miedema; Mark Redston; Jeannette M. Dowell; Donna Niedzwiecki; James W. Fleshman; Jiri Bem; Robert J. Mayer; Michael J. Zinner; Carolyn C. Compton; W. Douglas Wong; Frederick L. Greene; Stanley P. L. Leong; Merrick I. Ross

Objective and Summary Background Data:Sentinel lymph node (LN) sampling, a technique widely used to manage breast cancer and melanoma, seeks to select LNs that accurately predict regional node status and can be extensively examined to identify nodal metastatic disease not detected by standard histopathological staging. For patients with resectable colon cancer, improved identification of LN disease would significantly advance patient care by identifying patients likely to benefit from adjuvant therapy. This study, conducted by 25 surgeons at 13 institutions, examined whether sentinel node (SN) sampling accurately predicted LN status for patients with resectable colon cancer. Methods:SN sampling involved peritumor injection of 1% isosulfan blue, followed by identification of all LN visualized within 10 minutes. SN sampling was performed on 79 of 91 patients enrolled, followed by multilevel sectioning (MLS) of the nodes and examination by a single study pathologist. Results:By standard histopathology, 7 patients had primary disease that was either benign or not colon cancer and were therefore excluded from further studies. Of 72 colon cancer cases studied, 48 (66%) were node-negative and 24 (33%) contained nodal metastases. SNs were successfully located in 66 cases (92%), with an average of 2.1 nodes per patient. SNs were negative in 14 of 24 node-positive cases (58%). MLS revealed tumor in a SN in 1 of these cases, bringing the false-negative rate of SN examination to 54%. Conclusion:This multi-institutional study found that for patients with node-positive colon cancer, SN examination with MLS failed to predict nodal status in 54% of cases. We conclude that SN sampling with MLS, used alone, is unlikely to improve risk stratification for resectable colon cancer.


Annals of Surgery | 1984

The diagnosis and treatment of pyogenic liver abscesses.

Brent W. Miedema; Peter Dineen

Pyogenic liver abscesses in 106 adult patients at The New York Hospital were reviewed to define optimum treatment. Mortality in the surgically treated patients was 26% (17/65), while those treated nonsurgically had a fatality rate of 95% (39/41). Multiple abscesses treated surgically had a surprisingly low mortality of 29% (5/17). Modern noninvasive tests are highly sensitive in diagnosing liver lesions greater than 2 cm. Difficulty remains in identifying small hepatic abscesses and differentiating large abscesses from tumor. Most liver abscesses have an identifiable source outside the liver. The most common source (31%) was cholangitis secondary to extrahepatic biliary obstruction. Multiple abscesses, mixed organisms, hyperbilirubinemia, and abscess complications are all associated with a significantly increased mortality. However, the lethality of the primary disease process was the most important factor determining survival. Most patients who have the underlying pathogenesis of the abscess controlled will survive surgical treatment. Transperitoneal surgical drainage and antibiotics remain the mainstay of treatment. Percutaneous drainage is recommended for high risk patients only.


Annals of Surgical Oncology | 2001

Distal Margin Requirements After Preoperative Chemoradiotherapy for Distal Rectal Carcinomas: Are ≤ 1 cm Distal Margins Sufficient?

Boris W. Kuvshinoff; Irfan Maghfoor; Brent W. Miedema; Mark P. Bryer; Steven Westgate; John D. Wilkes; David M. Ota

Background:Sphincter-sparing alternatives to abdominoperineal resection (APR) in the treatment of rectal cancer often are underused out of concern for inadequate distal margins and local failure. The present study addresses whether sphincter-sparing techniques with distal margins ≤ 1 cm adversely influence oncological outcome in patients given preoperative chemoradiotherapy.Methods:Thirty-seven patients with rectal cancer ≤ 8 cm from the anal verge were enrolled in the study. Preoperative external beam radiotherapy (5400 Gy) was administered together with continuous infusion of 5-fluorouracil (300 mg/m2/day). Surgical resection was performed in 36 patients with pathological assessment of tumor response and margins. Patients with sphincter-sparing resection and distal margins > 1 cm or ≤ 1 cm and those who underwent APR were compared.Results:Thirty-six patients completed preoperative chemoradiotherapy, with successful sphincter-preservation in 28 patients. At a median follow-up of 33 months, there were 12 recurrences overall, which included 11 distant failures and four pelvic failures. Disease-free survival (DFS) was not different between those who had an APR compared with sphincter-sparing resection with distal margins ≤ 1 cm. DFS was worse (P < .02) when radial margins were ≤ 3 mm compared with > 3 mm.Conclusions:Sphincter preservation is feasible in more than 75% of patients with tumors ≤ 8 cm from the anal verge after preoperative chemoradiotherapy. Sphincter-sparing surgery with distal margins ≤ 1 cm can be used without adversely influencing local recurrence or DFS. Limited radial margins (≤ 3 mm), however, are associated with increased disease recurrence.


Journal of Surgical Oncology | 1998

Review article: Micrometastasis in colorectal carcinoma: A review

Robert Calaluce; Brent W. Miedema; Yohannes W. Yesus

Lymph node metastasis is the most important predictor of prognosis, after surgery, in colorectal carcinoma. The term “micrometastasis” has evolved from a morphological definition to one that is used with molecular‐based techniques. We review the literature to evaluate the significance of detecting micrometastases in colorectal carcinoma, either by morphological or molecular techniques, and address technical difficulties encountered with both. Routine use of immunohistochemistry is not recommended as most studies show little change in staging or prognosis. Radioimmunoguided surgery may prove beneficial, but problems of false positives in benign diseases need to be addressed. Immunohistochemical detection of micrometastatic deposits in bone marrow aspirates holds the most promise for clinical practice. Molecular techniques are more sensitive than immunohistochemistry, but prognostic value needs to be determined. Molecular diagnostics can also determine genetic alterations and mutations that should improve our understanding of metastatic colon cancer and staging accuracy. J. Surg. Oncol. 1998;67:194–202.


Journal of The American College of Surgeons | 2009

Laparoscopic Appendectomy—Is it Worth the Cost? Trend Analysis in the US from 2000 to 2005

Emanuel Sporn; Gregory F. Petroski; Gregory J. Mancini; J. Andres Astudillo; Brent W. Miedema; Klaus Thaler

BACKGROUND Although laparoscopic appendectomy is widely used for treatment of appendicitis, it is still unclear if it is superior to the open approach. STUDY DESIGN From the Nationwide Inpatient Sample 2000 to 2005, hospitalizations with the primary ICD-9 procedure code of laparoscopic (LA) and open appendectomy (OA) were included in this study. Outcomes of length of stay, costs, and complications were assessed by stratified analysis for uncomplicated and complicated appendicitis (perforation or abscess). Regression methods were used to adjust for covariates and to detect trends. Costs were rescaled using the hospital and related services portion of the Medical Consumer Price Index. RESULTS Between 2000 and 2005, 132,663 (56.3%) patients underwent OA and 102,810 (43.7%) had LA. Frequency of LA increased from 32.2% to 58.0% (p < 0.001); conversion rates decreased from 9.9% to 6.9% (p < 0.001). Covariate adjusted length of stay for LA was approximately 15% shorter than for OA in both uncomplicated and complicated cases (p < 0.001). Adjusted costs for LA were 22% higher in uncomplicated appendicitis and 9% higher in patients with complicated appendicitis (p < 0.001). Costs and length of stay decreased over time in OA and LA. The risk for a complication was higher in the LA group (p < 0.05, odds ratio=1.07, 95% CI 1.00 to 1.14) with uncomplicated appendicitis. CONCLUSIONS LA results in higher costs and increased morbidity for patients with uncomplicated appendicitis. Nevertheless, LA is increasingly used. Patients undergoing LA benefit from a slightly shorter hospital stay. In general, open appendectomy may be the preferred approach for patients with acute appendicitis, with indication for LA in selected subgroups of patients.


Journal of Clinical Oncology | 2006

Analysis of Micrometastatic Disease in Sentinel Lymph Nodes From Resectable Colon Cancer: Results of Cancer and Leukemia Group B Trial 80001

Mark Redston; Carolyn C. Compton; Brent W. Miedema; Donna Niedzwiecki; Jeannette M. Dowell; Scott D. Jewell; James M. Fleshman; Jiri Bem; Robert J. Mayer; Monica M. Bertagnolli

PURPOSE To determine whether sentinel lymph node (LN) sampling (SLNS) could reduce the number of nodes required to characterize micrometastatic disease (MMD) in patients with potentially curable colon cancer. PATIENTS AND METHODS Cancer and Leukemia Group B 80001 was a study to determine whether SLNS could identify a subset of LNs that predicted the status of the nodal basin for resectable colon cancer and, therefore, could be extensively evaluated for the presence of micrometastases. Patients enrolled onto this study underwent SLNS after injection of 1% isosulfan blue, and both sentinel nodes (SNs) and non-SNs obtained during primary tumor resection were sectioned at multiple levels and stained using anti-carcinoembryonic antigen and anticytokeratin antibodies. RESULTS Using standard histopathology, SNs failed to predict the presence of nodal disease in 13 (54%) of 24 node-positive patients. Immunostains were performed for patients whose LNs were negative by standard histopathology. Depending on the immunohistochemical criteria used to assign LN positivity, SN examination resulted in either an unacceptably high false-positive rate (20%) or a low sensitivity for detection of MMD (40%). CONCLUSION By examining both SNs and non-SNs, this multi-institutional study showed that SNs did not accurately predict the presence of either conventionally defined nodal metastases or MMD. As a result, SLNS is not a useful technique for the study of MMD in patients with colon cancer.


Gastroenterology | 1992

Human gastric and jejunal transit and motility after Roux gastrojejunostomy

Brent W. Miedema; Keith A. Kelly; Michael Camilleri; Russell B. Hanson; Alan R. Zinsmeister; Michael K. O'Connor; Manuel L. Brown

Upper gut transit and motility among 10 symptomatic and 9 asymptomatic patients with Roux gastrectomy were compared with those among 10 healthy, unoperated controls. Gastric emptying of solids and Roux limb and small intestinal transit of liquids were assessed scintigraphically. Motor patterns in the Roux limb or healthy jejunum were recorded manometrically. Whereas gastric emptying was sometimes faster and sometimes unchanged after Roux gastrectomy compared with controls, Roux limb transit in patients was consistently slower than jejunal transit in controls. Postprandially, the Roux limb showed decreased overall motility, fewer clustered waves, and less aboral migration of clustered waves than the healthy jejunum. Symptomatic Roux patients had jejunal transit and motor patterns similar to those of asymptomatic patients. Nonetheless, reflux from Roux limb to gastric remnant occurred in 4 of 10 symptomatic patients but in none of the asymptomatic patients. In conclusion, stasis and dysmotility are present in the Roux limb after Roux gastrectomy and Roux-gastric reflux can occur. Other factors, however, must have a role in determining whether symptoms appear.

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