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Douglas K Rex

Publications and source records attributed to Douglas K Rex.

At least 55 records · Page 3Linked to original sources
PubMed2005

Colonoscopic polypectomy.

Despite the frequency with which polypectomy is performed, there is a paucity of information on what technical aspects of polypectomy most effectively remove polyps and minimize complications. The practice of polypectomy is based largely on the observational experience of experts and what gastroenterology fellows have learned from their attending physicians and from experts in postgraduate courses. Moreover, polypectomy technique is not consistent across the United States. In this technique update, the author presents his own methods for treating and observing small, large pedunculated, and large sessile polyps and discusses the advantages, disadvantages, and complications of each technique.

Clinical Trials as Topic↗
PubMed2004

A nursing perspective on sedation and nurse-administered propofol for endoscopy.

Although the role of nurses in endoscopic sedation and monitoring varies widely, our experience has been that an active role of nurses in the administration of sedation and in patient monitoring has been safe for patients, has allowed expansion of the use of propofol in GI endoscopy in a cost-effective fashion, and has been satisfying to patients and nurses. In addition, in some instances nurse administration of sedation has improved the efficiency of the endoscopy unit. The role of nurses in endoscopic sedation and monitoring continues to develop, and we are enthusiastic about an active role for nurses.

Procedural Sedation↗
PubMed2004

A novel shape-locking guide for prevention of sigmoid looping during colonoscopy.

BACKGROUND: Looping of the endoscope in the sigmoid colon and other colonic segments often represents a significant challenge to the performance of comfortable, complete, and swift colonoscopy. This report describes the design and operation of a new device that addresses this problem, together with preliminary preclinical experience with this use of this shape-locking guide (SG-1). METHODS: The shape-locking guide is an overtube that can be converted from a flexible to a rigid configuration on demand. When in the rigid configuration, the shape-locking guide is designed to protect the colon wall from lateral forces exerted by the colonoscope. The shape-locking guide was evaluated in vitro by using an artificial colon model to learn how to operate it, and to assess feasibility for prevention of colon looping. In addition, safety was assessed in vivo in a pig model. RESULTS: In vitro, the shape-locking guide prevented colonic looping and, thereby, aided completion of "colonoscopy" in the artificial colon model. Subsequent in vivo studies demonstrated that use of the shape-locking guide is safe and feasible; it performed well with respect to ease of insertion and avoidance of sigmoid looping. There was no evidence of significant injury to the colon or adjacent abdominal viscera. CONCLUSIONS: This preliminary study shows that use of the shape-locking guide is safe and that it has performance characteristics that may assist the performance of colonoscopy. Human trials are being undertaken.

Animals↗
PubMed2004

A survey of colonoscopic polypectomy practices among clinical gastroenterologists.

BACKGROUND: Polypectomy techniques vary in clinical practice. The aim of this study was to determine patterns of polypectomy practices in a random sample of gastroenterologists. METHODS: A total of 300 gastroenterologists were selected randomly from the membership directory of a professional society. They were asked to complete a standardized survey by telephone, electronic mail, or facsimile. RESULTS: The offices of 285 physicians were contacted successfully. A total of 189 (63%) chose to participate. 152 (80%) of these physicians were in private practice, and 37 (20%) were in academic practice. The mean number of years in practice was 15.5 (range 1-46 years). Forceps techniques (cold or hot) dominated other polypectomy methods for polyps 1 to 3 mm in size ( p < 0.0001), whereas electrosurgical snare resection was dominate for polyps 7 to 9 mm in diameter ( p < 0.0001). No method of polypectomy was significantly more likely to be used for polyps 4 to 6 mm in size. The proportion of physicians who had used dye spraying was 8.5%; detachable snares, 20.1%; clips, 20.1%; and submucosal saline solution injection, 82%. Of those who had used submucosal saline solution injection, 29.7% had no rules for its use, and, in the remainder, there was marked variation regarding the criteria. For polyp stalks greater than 1 cm in diameter, 69% used no method to prevent bleeding. Of those who did use preventive techniques, 76% used epinephrine injection. The electrosurgical current used for polypectomy was pure coagulation in 46%, blend in 46%, and pure-cut in 3%; 4% varied the current. CONCLUSIONS: At present, polypectomy technique among clinical gastroenterologists is highly variable. Some newer ancillary techniques have had extremely limited use thus far.

Colonic Polyps↗
PubMed2004

Technical performance of colonoscopy in patients sedated with nurse-administered propofol.

OBJECTIVES: Nurse-administered propofol has gained attention as a safe and effective means of sedation for patients undergoing endoscopic procedures. However, little is known about the effect of propofol on the technical performance of colonoscopy. METHODS: Three separate studies were conducted. In the first study, we reviewed procedure notes from consecutive colonoscopies performed by a single experienced endoscopist at our hospital endoscopy unit on patients sedated with either nurse-administered propofol (n = 162) or midazolam/narcotic (n = 164). In the second study, 100 eligible colonoscopy outpatients were randomized to receive either nurse-administered propofol (n = 50) or midazolam/fentanyl (n = 50). In both studies, the measured parameters included visualization of the cecum, time required to reach the cecum, repositioning of the patient, and the application of abdominal counterpressure. In a third study, we reviewed the rate of cecal intubation and colonic perforation in the first 2357 patients in our unit receiving nurse-administered propofol. RESULTS: In the retrospective comparative study, there was no difference in the cecal intubation rate in those receiving propofol (99.4%) compared to those receiving midazolam/narcotic (97%; p= 0.1), and three of five failed cecal intubations in the latter group resulted from obstructing masses. Patients sedated with propofol were repositioned less frequently compared to those receiving midazolam/narcotic (3.7%vs 26.2%) (p < 0.0001). Abdominal pressure was employed in 9.9% of patients sedated with propofol compared to 19.5% (p= 0.01) of those given midazolam/narcotic. The mean time to reach the cecum was lower in the propofol group than in the midazolam/narcotic group (4.6 min vs 6.0 min, p= 0.002). In the prospective randomized study, the endoscopist intubated the cecum in all 100 patients. Patients in the propofol group were repositioned less frequently than those in the midazolam/fentanyl group (2%vs 24%, respectively, p= 0.001). The number of cases requiring abdominal counterpressure was not significantly different between the propofol and midazolam/fentanyl groups (12%vs 24%, respectively, p= 0.1). The mean time to reach the cecum in the propofol group (3.2 min) was similar to that in the midazolam/fentanyl group (3.8 min, p= 0.08). Among the first 2357 patients in our unit undergoing colonoscopy with nurse-administered propofol, the rate of complete colonoscopy was 99.2% and there were no perforations. CONCLUSION: Nurse-administered propofol sedation is safe and simplifies the technical performance of colonoscopy compared to midazolam/narcotic sedation.

Analgesics, Opioid↗
PubMed2004

An initial investigation of bispectral monitoring as an adjunct to nurse-administered propofol sedation for colonoscopy.

BACKGROUND AND AIMS: Bispectral (BIS) monitoring has been used to evaluate depth of sedation in intensive care and surgical patients. We sought to explore its utility as a monitoring device for nurse-administered propofol sedation (NAPS) during colonoscopy. METHODS: Fifty consecutive patients (ASA I or II) receiving NAPS for outpatient colonoscopy were evaluated. BIS scores, sedation scores, and propofol dosing were correlated. The nurses assessed the usefulness of BIS by questionnaire. RESULTS: The mean (SD) dose of propofol required to produce a BIS value </= 60 was 109.4 (43.9) mg and an Observer's Assessment of Alertness/Sedation (OAA/S) score of 1 (deep sedation) was 91.4 (44.8) mg (p < 0.0001). The mean times required to achieve BIS values </= 60 (188 +/- 147.1 s) and </= 70 (164.3 +/- 95.1 s) were significantly longer than the mean time required to achieve an OAA/S of 1 (117.4 +/- 93.0 s, p= 0.0007). Similarly, during the recovery phase, there was a lag time of 197.9 s between mean (SD) time required from the last dose of propofol to an OAA/S of 5 (372.1 +/- 197.1 s) and the mean (SD) time required from the last dose of propofol to a BIS value >/= 90 or return to baseline (570 +/- 279.9 s, p < 0.0001). The mean (SD) BIS value in the maintenance phase of sedation was 58.9 (8.53), with a range of 22-88. Nurses administering propofol rated the usefulness of BIS at a mean of 2.85 (maximum usefulness scored as 4) in guiding the dosing of propofol sedation during the maintenance phase of sedation. No patient required mask ventilation or endotracheal intubation. CONCLUSIONS: The BIS index in its current version is not useful in titrating boluses of propofol to an adequate level of sedation, because there is a substantial lag time between decrease of BIS scores to <70 and OAA/S scores indicative of deep sedation. There is also a substantial lag time between recovery of alertness and return of BIS scores to normal. A controlled trial of whether BIS values can assist in avoiding unnecessary propofol dosing during the maintenance phase of sedation appears warranted.

Adult↗
PubMed2004

Impact of proximal colon retroflexion on adenoma miss rates.

BACKGROUND: Small adenomas are commonly missed during routine colonoscopy. The aim of this study was to determine whether routine retroflexion in the proximal colon would improve adenoma detection rates. METHODS: One hundred patients underwent colonoscopy from the cecum to the splenic flexure by a gastroenterology fellow, with the removal of all visualized polyps. The cecum was then reintubated and patients were randomized to a second exam of the proximal colon by an experienced staff physician in either the forward view or a retroflexed view. RESULTS: Two patients were excluded due to a difficult initial cecal intubation. Forty-eight patients were randomized to forward view and 50 patients were randomized to a retroflexed view. Retroflexion was successful in the cecum in 60%, the ascending colon 100%, and the transverse colon 98%. The success in retroflexion was determined in part by the type of colonoscope used. If any portion of the retroflexed examination could not be performed, that reexamination was performed in the forward view. The calculated miss rates for all polyps and adenomas among patients randomized to second examination in the forward view was 36.8% and 33.3%, respectively. The calculated miss rate for all polyps and for adenomas among patients randomized to a second examination in the retroflexed view was 38.1% and 23.7%, respectively. There was no difference in miss rates for all polyps or for adenomas (p= 0.31) when the second examination was performed in the forward view versus retroflexed view. CONCLUSIONS: A second examination by retroflexion in the proximal colon did not increase the calculated miss rate relative to that performed by a forward view examination. These results do not support the addition of routine right colon retroflexion to colonoscopy.

Adenoma↗
PubMed2004

170 degrees wide-angle colonoscope: effect on efficiency and miss rates.

BACKGROUND: Small polyps are routinely missed during colonoscopy even with careful examination. AIM: To determine and compare endoscopic efficiency and polyp miss rate between a prototype 170 degrees wide-angle (WA) colonoscope and a standard (S) colonoscope. METHODS: Two consecutive same-day colonoscopies were performed in 50 patients with intact colons. The patients were randomized to undergo the first colonoscopy with either the prototype WA 170 degrees angle of view colonoscope or an S adult 140 degrees angle of view colonoscope. RESULTS: The mean time for insertion was 2.09 (1.09) min versus 2.53 (1.47) min (p= 0.002) for the WA colonoscope and the S colonoscope, respectively. Similarly, the mean time for examination during withdrawal was shorter with the WA colonoscope (4.98 (0.94) vs 5.74 (1.12) min; p < 0.0001). The mean insertion time for the second examination was shorter than the insertion time for the first examination, irrespective of the colonoscope (p= 0.006). However, the withdrawal times were not significantly different between the first and second examinations (p= 0.11). The miss rate for all polyps with the WA colonoscope (19%) was similar to the miss rate with the S colonoscope (27%; p= 0.19). The miss rates for adenomas with the WA (10/33; 30.3%) and the S scope (15/50; 30%) were similar (p= 0.98). CONCLUSIONS: The use of the WA colonoscope was associated with a reduction in insertion time to the cecum, as well as examination time during withdrawal. No evidence was found that the accuracy of the two colonoscopes differs.

Adenoma↗
PubMed2004

The science and politics of propofol.

Propofol use for endoscopy is increasing rapidly. Its administration by registered nurses under the supervision of endoscopists has thus far proven safe, but is not realistically feasible in most U.S. endoscopy units. Therefore, propofol in the United States is being administered almost entirely by anesthetists. Transition to anesthetist-delivered sedation for endoscopy is being accompanied by increased costs, which in turn has the potential to adversely affect endoscopic practice. The gastroenterology and anesthesia communities should work together to explore mechanisms to expand propofol use or an alternative for endoscopy in a safe and cost-effective manner.

Anesthesiology↗
PubMed2004

Fecal-based DNA assays: a new, noninvasive approach to colorectal cancer screening.

Stool-based DNA testing is a new, noninvasive method of colorectal cancer screening. Because it is easier to use and more sensitive than fecal occult blood testing, physicians may be more likely to recommend it, and patients may be more apt to comply. Although it is expensive, initial assessments show it to be cost-effective.

Colorectal Neoplasms↗
PubMed2004

Colorectal cancer in African Americans.

In the United States, African Americans have the highest incidence of colorectal cancer of any racial or ethnic group. Compared with whites, African Americans have a younger mean age at colorectal cancer diagnosis and a greater proportion have proximal cancers. Survival in African Americans with colorectal cancer is lower than in whites. Currently, there are no established biological explanations for these differences in colorectal cancer between African Americans and whites. As leaders in the prevention and early diagnosis of colorectal cancer in the United States, clinical gastroenterologists can play an important role in promoting colorectal cancer awareness and the need for screening in African Americans.

Adult↗
PubMed2003

Bowel obstruction and pseudo-obstruction.

The gastroenterologist is frequently involved in the care of patients with bowel obstruction and pseudo-obstruction. In the case of obstruction, the central problem is determining which patients should be managed surgically. In both SBO and LBO, evidence of vascular compromise to the gut mandates surgical intervention. Most patients with pseudo-obstruction respond to conservative therapy or neostigmine. Endoscopic decompression is indicated in recalcitrant cases, with surgery reserved as a last resort.

Algorithms↗
PubMed2003

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

BACKGROUND & AIMS: Propofol is under evaluation as a sedative for endoscopic procedures. We compared nurse-administered propofol to midazolam plus fentanyl for outpatient colonoscopy. METHODS: One hundred outpatients undergoing colonoscopy were randomized to receive propofol or midazolam plus fentanyl, administered by a registered nurse and supervised only by an endoscopist. Endpoints were patient satisfaction, procedure and recovery times, neuropsychologic function, and complications. RESULTS: The mean dose of propofol administered was 277 mg; mean doses of midazolam and fentanyl were 7.2 mg and 117 microg, respectively. Mean time to sedation was faster with propofol (2.1 vs. 6.1 min; P<0.0001), and depth of sedation was greater (P<0.0001). Patients receiving propofol reached full recovery sooner (16.5 vs. 27.5 min; P=0.0001) and were discharged sooner (36.5 vs. 46.1 min; P=0.01). After recovery, the propofol group scored better on tests reflective of learning, memory, working memory span, and mental speed. Six minor complications occurred in the propofol group: 4 episodes of hypotension, 1 episode of bradycardia, and 1 rash. Five complications occurred with the use of midazolam and fentanyl: one episode of oxygen desaturation requiring mask ventilation and 4 episodes of hypotension. Patients in the propofol vs. midazolam and fentanyl groups reported similar degrees of overall satisfaction using a 10-cm visual analog scale (9.3 vs. 9.4, P>0.5). CONCLUSIONS: Nurse-administered propofol resulted in several advantages for outpatient colonoscopy compared with midazolam plus fentanyl, but did not improve patient satisfaction.

Adjuvants, Anesthesia↗