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Douglas K Rex

Publications and source records attributed to Douglas K Rex.

90 records · Page 5Linked to original sources
PubMed2002

Chemoprevention of colorectal cancer by aspirin: a cost-effectiveness analysis.

BACKGROUND & AIMS: The aim of the study is to compare the cost-effectiveness of aspirin and colonoscopy in the prevention of colorectal cancer. METHODS: A Markov process is used to follow a hypothetical cohort of 100,000 subjects aged 50 years until death. Four strategies are compared: (1) no intervention, (2) colonoscopy once per 10 years and every 3 years in subjects with polyps, (3) chemoprevention with 325 mg of daily aspirin, and (4) combination of the second and third strategies. The various strategies are compared calculating incremental cost-effectiveness ratios (ICERs). RESULTS: The expected number of colorectal cancers is 5904 per 100,000 subjects. Colonoscopy prevents 4428 colorectal cancers and saves 7951 life-years at an ICER of $10,983 per life-year saved compared with no intervention. Aspirin prevents 2952 colorectal cancers and saves 5301 life-years at an ICER of $47,249 per life-year saved compared with no intervention. The cost of aspirin therapy plus management of aspirin-related complications was reported to be $172 per year per patient. Varying the annual aspirin-related costs between $50 and $200 results in ICER changes between $4617 and $57,080, with the 2 strategies breaking even at $70. Applying aspirin chemoprevention plus colonoscopy screening concomitantly yields an ICER of $227,607 per life-year saved compared with screening colonoscopy alone. CONCLUSION: As compared with colonoscopy once per 10 years, the use of aspirin to prevent colorectal cancer saves fewer lives at higher costs. The high complication cost and the lower efficacy of aspirin render screening colonoscopy a more cost-effective strategy to prevent colorectal cancer.

Aged↗
PubMed2002

Efficacy and complications of argon plasma coagulation for hematochezia related to radiation proctopathy.

BACKGROUND: Endoscopic treatments effectively control bleeding caused by radiation proctopathy. The aims of this study were to determine the efficacy and side effects of argon plasma coagulation in the treatment of this type of bleeding. METHODS: Records of 21 consecutive patients in whom argon plasma coagulation was used to treat hemorrhagic radiation proctopathy were reviewed. RESULTS: Pharmacologic measures had been unsuccessful in 12 patients. Endoscopic treatment had been unsuccessful in 5 patients. All patients were anemic and 4 had received blood transfusions. The mean number of treatment sessions was 1.7, and 10 patients were successfully treated in single session. Rectal bleeding resolved within 1 month of the last treatment in 19 patients, usually on the day of the last procedure. Bleeding resolved 2 months after cessation of therapy in another patient. Short-term side effects occurred in 3 (14%) patients (rectal pain, tenesmus, and/or abdominal distention); long-term complications (rectal pain, tenesmus, diarrhea) developed in 4 patients (19%). CONCLUSIONS: Hematochezia caused by radiation proctopathy is effectively controlled by argon plasma coagulation, in some cases after a single treatment session. Treatment may result in protracted bowel symptoms.

Aged↗
PubMed2002

Propofol versus midazolam/meperidine for outpatient colonoscopy: administration by nurses supervised by endoscopists.

BACKGROUND: Propofol is under evaluation as a sedative for endoscopic procedures. METHODS: Eighty outpatients (ASA Class I or II) undergoing colonoscopy were randomized to receive either propofol or midazolam plus meperidine, administered by a nurse and supervised by an endoscopist. Endpoints were patient satisfaction, procedure and recovery times, neuropsychological function, and complications. RESULTS: The mean dose of propofol administered was 218 mg; mean doses of midazolam and meperidine were, respectively, 4.7 mg and 89.7 mg. Mean time to sedation was faster in the propofol patients (2.1 min vs. 7.0 min; p < 0.0001), and depth of sedation was greater (p < 0.0001). On average, after the procedure, the propofol patients could stand at the bedside sooner (14.2 vs. 30.2 min), reached full recovery faster (14.4 vs. 33.0 min), and were discharged sooner (40.5 vs. 71.1 min) (all p < 0.0001). Patients who received propofol also expressed greater overall mean satisfaction on a 10-point visual analog scale (9.3 vs. 8.6; p < 0.05). At discharge, the propofol group had better scores on tests reflective of learning, memory, working memory span, and mental speed. Four patients in the midazolam/meperidine group developed minor complications (1 hypotension and bradycardia, 2 hypotension alone, and 1 tachycardia) and 1 patient in the propofol group had oxygen desaturation develop during an episode of epistaxis. CONCLUSION: For outpatient colonoscopy, propofol administered by nurses and supervised by endoscopists has several advantages over midazolam plus meperidine and deserves additional investigation.

Adult↗
PubMed2002

Method of colonoscopy in 42 consecutive patients presenting after prior incomplete colonoscopy.

OBJECTIVES: Cecal intubation is one of the goals of colonoscopy. We sought to describe the methodology used by a single experienced examiner to perform colonoscopy in a consecutive group of patients with challenging colons. METHODS: Records of 42 consecutive patients with one or more prior unsuccessful attempts at colonoscopy by a gastroenterologist or surgeon and referred for a repeat attempt at colonoscopy were reviewed. RESULTS: Colonoscopy was complete to the cecum in 40 of the 42 patients (95%). An array of methods was employed, including propofol sedation (n = 2), pediatric colonoscope (n = 8), an external straightener (n = 9), external straightener with pediatric colonoscope (n = 2), upper endoscope (n = 8), guidewire exchange (n = 3), and enteroscope with a colon straightener (n = 1) or an enteroscope straightener (n = 1). CONCLUSIONS: A variety of methods and instruments were employed to achieve a high cecal intubation rate during colonoscopy in a group of patients with prior incomplete colonoscopies. Others may find one or more of these methods useful in patients with challenging colons.

Adult↗
PubMed2002

Safety of propofol administered by registered nurses with gastroenterologist supervision in 2000 endoscopic cases.

OBJECTIVES: Propofol has certain advantages over benzodiazepines plus narcotics as sedation for endoscopy. In a few centers, propofol has reportedly been used in endoscopic procedures and administered by nurses supervised by gastroenterologists without attendance by anesthesiologists or nurse anesthetists. METHODS: As part of our continuous quality improvement program, we prospectively recorded the doses of propofol and adverse reactions to the drug in our initial 2000 cases. In all cases propofol was administered by nurses who were supervised by gastroenterologists, with no involvement by an anesthesia specialist. RESULTS: The 2000 cases included 2222 procedures. There were five episodes of oxygen desaturation to <85%, four of which seemed to be related to excessive administration of propofol and were treated by brief (< 1 min) periods of mask ventilation. No patient required endotracheal intubation or hospital admission, or suffered long-term sequelae from propofol administration. There were no perforations in 977 colonoscopies. CONCLUSIONS: Propofol can be given safely by appropriately trained nurses under supervision by endoscopists. Technology that allows immediate detection of apnea would likely further improve its safety.

Anesthetics, Intravenous↗
PubMed2002

Step section histology of proximal colon polyps that appear hyperplastic by endoscopy.

OBJECTIVE: Recent studies have identified a group of polyps, usually located in the proximal colon, with distinct endoscopic features that predict hyperplastic histology. These polyps may occasionally have foci of dysplastic (adenomatous) tissue. We aimed to define the prevalence of adenomatous foci in these polyps. METHODS: Fifty-one consecutive hyperplastic-appearing proximal colon polyps were sectioned at 1-mm intervals for histological analysis. RESULTS: All 51 polyps were hyperplastic, but two (4%) had foci of adenomatous tissue. CONCLUSION: The prevalence of adenomatous foci in proximal colon polyps with endoscopic features of hyperplastic polyps is low. Whether endoscopic resection of polyps with these features is warranted remains uncertain.

Adenoma↗
PubMed2002

Impact of bowel preparation on efficiency and cost of colonoscopy.

OBJECTIVES: The impact of bowel preparation on the cost and efficiency of colonoscopy is uncertain. The aim of this study was to measure the impact of bowel preparation on total direct cost as well as procedure time and volume. METHODS: For 200 consecutive outpatient colonoscopies in persons with intact colons both at a private university hospital and at a public university hospital, we recorded the time spent suctioning fluid and feces from the colon and the time spent washing the colon to clean the mucosa. We prospectively asked colonoscopists to designate examinations that should be repeated at an interval sooner than would otherwise be recommended because of imperfect preparation. The data were used to perform a cost analysis of the economic effect of bowel preparation on direct costs of colonoscopy. RESULTS: Suctioning fluid and washing occupied 6% and 1.5% of total examination time (including insertion and withdrawal) at the public hospital and 9% and 1.3% at the private hospital. Patients at the public hospital were more likely to have an aborted examination (6.5% vs 1%, p = 0.004) and to be brought back earlier than suggested or required by current practice standards because of imperfect bowel preparation (20% vs 12.5%, p = 0.04). Cost analysis indicated that to complete the initial examinations and the first round of surveillance, imperfect bowel preparation resulted in a 12% increase in costs at the university hospital and a 22% increase at the public hospital. CONCLUSIONS: The increase in colonoscopy costs associated with imperfect preparation is substantial, and seems likely to vary among practices. Aborted examinations and surveillance examinations performed earlier than recommended because of imperfect preparation are appropriate targets for continuous quality improvement programs. More reliable bowel preparations, or measures to improve patient compliance with bowel preparation, could significantly reduce the costs of colonoscopy in clinical practice.

Colonoscopy↗
PubMed2002

An initial investigation of efficiency in endoscopy delivery.

OBJECTIVE: The demand for endoscopic services is increasing rapidly. Of the several potential mechanisms to improve the supply of endoscopic procedures, improved efficiency in the endoscopy unit has received little attention. METHODS: We invited 20 experienced endoscopists to participate in an initial evaluation of endoscopy efficiency, in which they were observed performing procedures in their own unit. Procedure volume per unit time was used as the measure of efficiency. Medical directors and head nurses at each endoscopy unit were interviewed regarding factors they perceived as most important in limiting procedure volume. RESULTS: There was a greater than 3-fold variation in procedure volume score between the least efficient and most efficient endoscopists. The clearest trend predicting procedure volume score was short room turnover time (p = 0.0004). There was a trend toward improved procedure volume among endoscopists using another professional to sedate their patients and using two procedure rooms. The surveys of medical directors and head nurses suggested that multiple factors contribute to limiting procedure volume, but on average each perceived number of available doctors is the least important factor in limiting volume. CONCLUSIONS: Improving the efficiency of some endoscopists appears to be an important potential mechanism to meet the rising demand for endoscopic services. Increasing the resources that provide the opportunity for efficiency may be an important mechanism for increasing the availability of endoscopic services. Specific measures associated with improved efficiency include reduced room turnover times, and possibly use of two rooms per endoscopist and sedation by persons other than the endoscopist.

Efficiency, Organizational↗
PubMed2002

Considering virtual colonoscopy.

Virtual colonoscopy continues to show promise as a colorectal cancer screening test and is technically evolving rapidly. It has particular advantages with regard to acceptability by both radiologists and patients. Important steps to achieve implementation include clear delineation of all of the technical components necessary to produce consistent high performance and development of clear-cut recommendations for interpretation and management of polyps of various sizes and the range of extracolonic findings identified. Development of an effective methodology to perform the test without bowel preparation or demonstration of cost-effectiveness for identification and treatment of one or more significant extracolonic diseases would be major breakthroughs, provided they are still accompanied by effective detection of significant colon neoplasms. Issues regarding general effectiveness and cost-effectiveness must be resolved before virtual colonoscopy is endorsed for widespread colorectal cancer screening or utilized for that purpose.

Colonic Polyps↗
PubMed2002

Current colorectal cancer screening strategies: overview and obstacles to implementation.

Colorectal cancer is the second leading cause of cancer death but is largely preventable. Current strategies to prevent colorectal cancer vary considerably with regard to effectiveness, up-front costs, risks, and invasiveness. Current levels of participation in colorectal cancer screening in the U.S. population are low. Both physician and patient attitudes contribute to low levels of screening uptake. New colorectal cancer tests are one mechanism to improve adherence. Virtual colonoscopy may have an important impact if techniques to perform it without bowel preparation can be developed. Stool-based DNA testing is likely to be the most effective entirely noninvasive strategy and will be easier for patients to perform than fecal occult blood testing. The potential for improvements in the technology are substantial, and data from second-generation assays have already been reported. The cost-effectiveness of new strategies needs further evaluation.

Barium Sulfate↗
PubMedDate not supplied

Current and future trends in colorectal cancer screening.

Current modalities for colorectal cancer screening include fecal occult-blood testing, flexible sigmoidoscopy, colonoscopy, and double-contrast barium enema. Among these, colonoscopy is becoming the dominant modality, in light of its efficacy and continuing technical refinements. Emerging technologies, such as stool DNA tests and virtual colonoscopy, hold promise for the future but cannot be recommended for screening at present.

Barium Sulfate↗
PubMedDate not supplied

Positive predictive value of endoscopic features deemed typical of gastric fundic gland polyps.

BACKGROUND: Fundic gland polyps (FGPs) are now the most common gastric polyp encountered by endoscopists. However, they have minimal clinical significance. If they could be reliably predicted by endoscopic features, it might prevent the need for and cost of biopsy. GOALS: To determine the positive predictive value of endoscopic criteria deemed characteristic of FGPs. STUDY: We prospectively identified 56 consecutive patients with one or more gastric polyps deemed typical of FGPs by endoscopic criteria and submitted them for histologic analysis. Patients with familial adenomatous polyposis were excluded. RESULTS: Histologic examination confirmed that 50 (89.3%) of the 56 polyps were FGPs. Of the six polyps incorrectly predicted to be FGPs, three were determined to be of normal gastric body-type mucosa, one was uninterpretable secondary to squeeze artifact, one was a lymphoid aggregate with mucosal edema, and one was polypoid regenerative mucosa in the setting of chronic active gastritis and Helicobacter pylori infection. CONCLUSIONS: As sporadic FGPs are common and can be predicted with a high degree of accuracy based on endoscopic evaluation, it may not be necessary to submit them for pathologic examination. This practice would result in cost savings.

Adult↗
PubMedDate not supplied

Guidelines for colonoscopy surveillance after polypectomy: a consensus update by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society.

Adenomatous polyps are the most common neoplastic findings uncovered in people who undergo colorectal screening or have a diagnostic workup for symptoms. It was common practice in the 1970s for these patients to have annual follow-up surveillance examinations to detect additional new adenomas as well as missed synchronous adenomas. As a result of the National Polyp Study report in 1993, which demonstrated clearly in a randomized design that the first postpolypectomy examination could be deferred for 3 years, guidelines published by a gastrointestinal consortium in 1997 recommended that the first follow-up surveillance be 3 years after polypectomy for most patients. In 2003, these guidelines were updated, colonoscopy was recommended as the only follow-up examination, and stratification at baseline into lower and higher risk for subsequent adenomas was suggested. The 1997 and 2003 guidelines dealt with both screening and surveillance. However, it has become increasingly clear that postpolypectomy surveillance is now a large part of endoscopic practice, draining resources from screening and diagnosis. In addition, surveys have demonstrated that a large proportion of endoscopists are conducting surveillance examinations at shorter intervals than recommended in the guidelines. In the present paper, a careful analytic approach was designed addressing all evidence available in the literature to delineate predictors of advanced pathology, both cancer and advanced adenomas, so that patients can be more definitely stratified at their baseline colonoscopy into those at lower or increased risk for a subsequent advanced neoplasia. People at increased risk have either three or more adenomas, or high-grade dysplasia, or villous features, or an adenoma > or =1 cm in size. It is recommended that they have a 3-year follow-up colonoscopy. People at lower risk who have one or two small (< 1 cm) tubular adenomas with no high-grade dysplasia can have a follow-up in 5 to 10 years, whereas people with hyperplastic polyps only should have a 10-year follow-up as average-risk people. Recent papers have reported a significant number of missed cancers by colonoscopy. However, high-quality baseline colonoscopy with excellent patient preparation and adequate withdrawal time should minimize this and reduce clinicians' concerns. These guidelines were developed jointly by the US Multi-Society Task Force on Colorectal Cancer and the American Cancer Society to provide a broader consensus and thereby increase utilization of the recommendations by endoscopists. Adoption of these guidelines nationally can have a dramatic impact on shifting available resources from intensive surveillance to screening. It has been shown that the first screening colonoscopy and polypectomy produces the greatest effects on reducing the incidence of colorectal cancer in patients with adenomatous polyps.

Adenomatous Polyps↗
PubMedDate not supplied

Guidelines for colonoscopy surveillance after cancer resection: a consensus update by the American Cancer Society and US Multi-Society Task Force on Colorectal Cancer.

Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society (ACS) and US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stage II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double contrast barium enema or computed tomography colonography should be done preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that colonoscopy is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see Postpolypectomy Surveillance Guideline). Shorter intervals are also indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence, compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3- to 6-month intervals for the first 2 years after resection can be considered for the purpose of detecting a surgically curable recurrence of the original rectal cancer.

American Cancer Society↗