A novel blood-sensing capsule for rapid detection of upper GI bleeding: a prospective clinical trial

BACKGROUND AND AIMS

Upper GI bleeding (UGIB) is a common medical emergency associated with high resource utilization, morbidity, and mortality. Timely EGD can be challenging from personnel, resource, and access perspectives. PillSense (EnteraSense Ltd, Galway, Ireland) is a novel swallowed bleeding sensor for the detection of UGIB, anticipated to aid in patient triage and guide clinical decision-making for individuals with suspected UGIB.

METHODS

This prospective, open-label, single-arm comparative clinical trial of a novel bleeding sensor for patients with suspected UGIB was performed at a tertiary care center. The PillSense system consists of an optical sensor and an external receiver that processes and displays data from the capsule as "Blood Detected" or "No Blood Detected." Patients underwent EGD within 4 hours of capsule administration; participants were followed up for 21 days to confirm capsule passage.

RESULTS

A total of 126 patients were accrued to the study (59.5% male; mean age, 62.4 ± 14.3 years). Sensitivity and specificity for detecting the presence of blood were 92.9% (P = .02) and 90.6% (P < .001), respectively. The capsule's positive and negative predictive values were 74.3% and 97.8%, and positive and negative likelihood ratios were 9.9 and .08. No adverse events or deaths occurred related to the PillSense system, and all capsules were excreted from patients on follow-up.

CONCLUSIONS

The PillSense system is safe and effective for detecting the presence of blood in patients evaluated for UGIB before upper GI endoscopy. It is a rapidly deployed tool, with easy-to-interpret results that will affect the diagnosis and triage of patients with suspected UGIB. (Clinical trial registration number: NCT05385224.).

Acute Esophageal Necrosis: A Retrospective Cohort Study Highlighting the Mayo Clinic Experience

OBJECTIVE

To describe the clinical, endoscopic, and histologic features in patients with acute esophageal necrosis (AEN).

PATIENTS AND METHODS

In this retrospective cohort study, patients who were diagnosed as having AEN at Mayo Clinic sites in Minnesota, Florida, and Arizona between January 1, 1996, and January 31, 2021, were included. Data were collected on patient clinical characteristics and endoscopic and pathologic findings.

RESULTS

The study included 79 patients with AEN with a median (range) age of 64 years (12 to 91 years); 53 (67.1%) were men. Predominant presenting symptoms were hematemesis (49 of 79 [62.0%]), abdominal pain (29 [36.7%]), and melena (20 [25.3%]). Shock was the triggering event for AEN in 49 (62.0%). The 30- and 90-day mortality were 24.0% (19 of 79) and 31.6% (25), respectively. The presence of coexisting infection or bacteremia was significantly associated with 90-day mortality (P<.01). Endoscopically, involvement of the distal third only, distal two-thirds only, and entire esophagus was observed in 31.6% (24 of 76), 39.5% (30), and 29.0% (22), respectively. The length of esophageal involvement correlated with duration of hospitalization (P=.05). The endoscopic appearance of the esophageal mucosa ranged from predominantly white (21 of 44 [47.7%]) to mixed white and black (13 [29.6%]) to predominantly black (10 [22.7%]), and sloughing was present in 18 (40.9%). In the 26 patients with histopathologic findings available for review, 25 (96.1%) had necrosis and/or ulceration with abundant pigmentation. Among the 79 patients, 39 (49.4%) had a follow-up esophagogastroduodenoscopy; 26 of these 39 patients (66.7%) had resolution while 5 had persistent AEN, 4 of whom had improvement. Esophageal strictures developed in 7 of the 39 patients (18.0%).

CONCLUSION

Acute esophageal necrosis is a serious condition observed in critically ill patients. Its endoscopic appearance can be highly variable. In patients with an unclear diagnosis, esophageal biopsies may be helpful given the characteristic histologic findings.

Collaborative improvement on acute opioid prescribing among diverse health systems

Background

Despite broad awareness of the opioid epidemic and the understanding that patients require much fewer opioids than traditionally prescribed, improvement efforts to decrease prescribing have only produced modest advances in recent years.

Methods and findings

By using a collaborative model for shared expertise and accountability, nine diverse health care systems completed quality improvement projects together over the course of one year to reduce opioid prescriptions for acute pain. The collaborative approach was flexible to each individual system’s goals, and seven of the nine participant institutions definitively achieved their desired results.

Conclusions

This report demonstrates the utility of a collaborative model of improvement to bring about real change in opioid prescribing practices and may inform quality improvement efforts at other institutions.

Randomized Phase II Trial of Polyphenon E versus Placebo in Patients at High Risk of Recurrent Colonic Neoplasia

Polyphenon E (Poly E) is a green tea polyphenol preparation whose most active component is epigallocatechin gallate (EGCG). We studied the cancer preventive efficacy and safety of Poly E in subjects with rectal aberrant crypt foci (ACF), which represent putative precursors of colorectal cancers. Eligible subjects had prior colorectal advanced adenomas or cancers, and had ≥5 rectal ACF at a preregistration chromoendoscopy. Subjects (N = 39) were randomized to 6 months of oral Poly E (780 mg EGCG) daily or placebo. Baseline characteristics were similar by treatment arm (all P >0.41); 32 of 39 (82%) subjects completed 6 months of treatment. The primary endpoint was percent reduction in rectal ACF at chromoendoscopy comparing before and after treatment. Among 32 subjects (15 Poly E, 17 placebo), percent change in rectal ACF number (baseline vs. 6 months) did not differ significantly between study arms (3.7% difference of means; P = 0.28); total ACF burden was also similar (-2.3% difference of means; P = 0.83). Adenoma recurrence rates at 6 months were similar by arm (P > 0.35). Total drug received did not differ significantly by study arm; 31 (79%) subjects received ≥70% of prescribed Poly E. Poly E was well tolerated and adverse events (AE) did not differ significantly by arm. One subject on placebo had two grade 3 AEs; one subject had grade 2 hepatic transaminase elevations attributed to treatment. In conclusion, Poly E for 6 months did not significantly reduce rectal ACF number relative to placebo. Poly E was well tolerated and without significant toxicity at the dose studied. PREVENTION RELEVANCE: We report a chemoprevention trial of polyphenon E in subjects at high risk of colorectal cancer. The results show that polyphenon E was well tolerated, but did not significantly reduce the number of rectal aberrant crypt foci, a surrogate endpoint biomarker of colorectal cancer.

Evaluating a combined bowel preparation for small-bowel capsule endoscopy: a prospective randomized-controlled study

Background

Capsule endoscopy (CE) is frequently hindered by intra-luminal debris. Our aim was to determine whether a combination bowel preparation would improve small-bowel visualization, diagnostic yield, and the completion rate of CE.

Methods

Single-blind, prospective randomized–controlled study of outpatients scheduled for CE. Bowel-preparation subjects ingested 2 L of polyethylene glycol solution the night prior to CE, 5 mL simethicone and 5 mg metoclopramide 20 minutes prior to CE and laid in the right lateral position 30 minutes after swallowing CE. Controls had no solid food after 7 p.m. the night prior to CE and no liquids 4 hours prior to CE. Participants completed a satisfaction survey. Capsule readers completed a small-bowel-visualization assessment.

Results

Fifty patients were prospectively enrolled (56% female) with a median age of 54.4 years and 44 completed the study (23 patients in the control group and 21 in the preparation group). There was no significant difference between groups on quartile-based small-bowel visualization (all P > 0.05). There was no significant difference between groups in diagnostic yield (P = 0.69), mean gastric (P = 0.10) or small-bowel transit time (P = 0.89). The small-bowel completion rate was significantly higher in the preparation group (100% vs 78%; P = 0.02). Bowel-preparation subjects reported significantly more discomfort than controls (62% vs 17%; P = 0.01).

Conclusions

Combined bowel preparation did not improve small-bowel visualization but did significantly increase patient discomfort. The CE completion rate improved in the preparation group but the diagnostic yield was unaffected. Based on our findings, a bowel preparation prior to CE does not appear to improve CE performance and results in decreased patient satisfaction (ClinicalTrials.gov, No. NCT01243736).

Efficacy of Difluoromethylornithine and Aspirin for Treatment of Adenomas and Aberrant Crypt Foci in Patients with Prior Advanced Colorectal Neoplasms

Difluoromethylornithine (DFMO), an inhibitor of polyamine synthesis, was shown to act synergistically with a NSAID for chemoprevention of colorectal neoplasia. We determined the efficacy and safety of DFMO plus aspirin for prevention of colorectal adenomas and regression of rectal aberrant crypt foci (ACF) in patients with prior advanced adenomas or cancer. A double-blinded, placebo-controlled trial was performed in 104 subjects (age 46-83) randomized (1:1) to receive daily DFMO (500 mg orally) plus aspirin (325 mg) or matched placebos for one year. All polyps were removed at baseline. Adenoma number (primary endpoint) and rectal ACF (index cluster and total) were evaluated at a one year colonoscopy. ACF were identified by chromoendoscopy. Toxicity was monitored, including audiometry. Eighty-seven subjects were evaluable for adenomas or ACF modulation (n = 62). At one year of treatment, adenomas were detected in 16 (38.1%) subjects in the DFMO plus aspirin arm (n = 42) versus 18 (40.9%) in the placebo arm (n = 44; P = 0.790); advanced adenomas were similar (n = 3/arm). DFMO plus aspirin was associated with a statistically significant reduction in the median number of rectal ACF compared with placebo (P = 0.036). Total rectal ACF burden was also reduced in the treatment versus the placebo arm relative to baseline (74% vs. 45%, P = 0.020). No increase in adverse events, including ototoxicity, was observed in the treatment versus placebo arms. While adenoma recurrence was not significantly reduced by one year of DFMO plus aspirin, the drug combination significantly reduced rectal ACF number consistent with a chemopreventive effect.

Patient-oriented education and visual-aid intervention are inadequate to identify patients with potential capsule retention: a prospective randomized study

Background/aims: The key procedure-related risk with video capsule endoscopy (VCE) is capsule retention, which should be suspected in patients who have not reported capsule passage. The study aims were to determine the frequency of capsule passage visualization and the difference in self-reporting of capsule passage between patients who receive patient-oriented education (POE) and patients who receive POE and a visual aid intervention in the form of a wrist band (WB). Methods: This was a prospective randomized study that enrolled patients undergoing VCE. Patients were randomly assigned to a POE group versus a POE and WB group. POE consisted of verbal education and an information booklet. Both groups received instructions to notify the study team regarding capsule passage. Results: Sixty patients (mean age 57 ± 18 years; 61% female) were included. A total of 57 patients were included in the analysis (3 lost to follow-up; 28 in POE group; 29 in WB group). Capsule passage status was reported by 68% without significant difference between POE and WB groups (72% vs. 64%; p = .51). Capsule passage status was obtained from all 57 patients with the addition of a proactive follow-up. Only 56% (n = 32) reported visualizing capsule passage. Of the remaining patients who did not visualize capsule passage, 60% (n = 15) reported on this without significant difference between the POE and WB groups (p = .23). Conclusions: Lack of visualization of capsule passage is a poor indicator of retention. Self-reporting of VCE passage status is suboptimal and the addition of a visual aid did not improve this parameter.

A Collaborative for Implementation of an Evidence-Based Clinical Pathway for Enhanced Recovery in Colon and Rectal Surgery in an Affiliated Network of Healthcare Organizations

BACKGROUND

In 2015 the Mayo Clinic Care Network (MCCN), in an effort to extend medical knowledge and share these best practices, embarked on an education mission to diffuse the clinical practice redesign involving the practice of colon and rectal surgery at Mayo Clinic (Rochester, Minnesota) to members of the MCCN. They elected to use a collaborative framework in an attempt to transfer knowledge to multiple teams in an efficient and supportive manner.

METHODS

Eight MCCN members assembled a multidisciplinary team, which participated in both a didactic learning session delivered by frontline experts, as well as follow-up remote sessions regarding Mayo Clinic's enhanced recovery pathway for colon and rectal surgery. Teams departed the group session with established immediate next steps, communication plans, and an awareness of potential barriers and strategies for mitigation. Monthly coaching calls followed in an effort to help all teams meet their time line and overall goals. Finally, all participants met again after six months to report their clinical outcomes, as well their unique individual organization's successes and barriers encountered.

RESULTS

Participating teams felt overwhelmingly that the collaborative program exceeded their expectations and equipped them with the tools to be successful. They also felt that the extended support provided by the Mayo Clinic team was essential, and the collaboration with other members markedly enhanced their experience. Importantly, all teams were able to successfully reduce length of stay, which was the desired main clinical outcome.

DISCUSSION

The collaborative format was instrumental in the rapid diffusion and successful implementation of a transformative practice redesign involving colorectal surgical care of patients.

Overall Cost Comparison of Gastrointestinal Endoscopic Procedures With Endoscopist- or Anesthesia-Supported Sedation by Activity-Based Costing Techniques

OBJECTIVE

Endoscopic/colonoscopic procedures are either done with gastroenterologist-administered conscious sedation or with anesthesia-administered sedation with propofol. There are potential benefits to anesthesia-administered sedation, but the concern has been the associated increased cost.

METHODS

To perform this study, we used the time-derived activity-based costing (TDABC) technique to accurately assess the true cost of gastrointestinal procedures done with gastroenterologist-administered conscious sedation vs anesthesia-administered sedation in 2 areas of our practice that use predominantly conscious sedation or anesthesia-administered sedation. This type of study has never been reported using such an integrated approach. This study was performed on 2 different days in June 2015.

RESULTS

The true cost associated with anesthesia-administered sedation in our practice was associated with only 9% to 24% greater cost when the TDABC technique was applied.

CONCLUSION

Gastrointestinal procedures with anesthesia-administered sedation are not as costly when all factors are considered. Using novel approaches to cost measurement, such as the TDABC, allows a total cost measurement approach across an episode of care that existing cost measurements in health care are incapable of.

Endoscopic management of radiation-induced complete upper esophageal obstruction with an antegrade-retrograde rendezvous technique

BACKGROUND

Esophageal strictures occur in 3% to 4% of patients with head and neck cancer who undergo radiation therapy. Some patients develop complete obstruction of the upper esophagus. Antegrade dilatation is often unsuccessful and many of these patients require surgery.

OBJECTIVE

To describe the outcomes and complications of an endoscopic antegrade-retrograde rendezvous procedure to restore esophageal patency.

DESIGN

Retrospective review of 8 cases treated with an endoscopic rendezvous procedure between August 2001 and April 2005. Medical records of consenting patients were abstracted for clinical history, procedural success, complications, and follow-up.

SETTING

A large tertiary referral center.

PATIENTS

Eight patients with head and neck or upper esophageal cancer and complete upper esophageal obstruction from radiation stricturing who underwent an attempted rendezvous procedure.

MAIN OUTCOME MEASUREMENTS

Clinical procedural success, reported adverse events.

RESULTS

Seven patients were men, and median age was 65 years. The median interval between radiation and the rendezvous procedure was 11 months. In 7 of 8 cases esophageal patency was restored and no major complications occurred. Two esophageal microperforations resolved without intervention. Most patients responded well to subsequent serial dilations and many discontinued gastrostomy tube use.

LIMITATIONS

Retrospective, selection bias.

CONCLUSIONS

An antegrade-retrograde rendezvous technique with subsequent dilation appears to be safe and effective for endoscopic management of complete upper esophageal obstruction induced by radiotherapy and can obviate the need for esophageal resection.

Incident rates of colonic neoplasia in older patients: when should we stop screening?

INTRODUCTION

Current guidelines endorse colon cancer screening every 5-10 years in patients over 50 years of age. However, there is no consensus regarding what age is appropriate to stop screening. The aim of this study was to characterize neoplasia occurrence/recurrence in a large cohort of patients > or =70 years of age undergoing colonoscopy.

METHODS

The Mayo Rochester endoscopic database was reviewed to determine the incidence of colonic neoplasia in patients > or =70 years undergoing two colonoscopies at least 12 months apart between January 1996 and December 2000. Patients were classified based on (i) age: 70-74, 75-79, > or =80 years; and (ii) polyp detection on initial examination, that is, subsequent examination for screening or surveillance.

RESULTS

Overall, 1353 patients underwent two colonoscopies at least 12 months apart (median interval 140 weeks) with removal of polyp on initial examination in 726 (53.7%) patients (surveillance cohort). On subsequent endoscopy, polyps > or =10 mm were detected in 54 (4.0%) and cancer in 13 (1.0%) patients. All age groups were well matched with respect to detection of neoplasia on index examination (P = 0.9) and polyp size on initial colonoscopy among the surveillance group (P = 0.9). Using a Cox proportional hazards model, adjusted hazard ratios (95% confidence interval [CI]) for neoplasia (polyps > or =10 mm) were: 2.0 (1.50-2.73, P < 0.0001) (surveillance vs screening), 1.33 (0.96-1.79, P = 0.08) (> or =80 vs 70-74), and 1.05 (0.78-1.38, P = 0.75) (75-79 vs 70-74). Adjusted hazard ratios for development of cancer were: 1.87 (1.03-3.97, P = 0.04) (surveillance vs screening), 1.73 (0.84-3.56, P = 0.13) (> or =80 vs 70-74), and 1.38 (0.71-2.77, P = 0.34) (75-79 vs 70-74).

CONCLUSIONS

Prior history of neoplasia remains a strong risk factor for colorectal neoplasia development in elderly patients and should be considered when deciding the need for continuing screening/surveillance. Incident neoplasia rates in a previously screened elderly population rise slowly with advancing age although cancer rates rise more sharply. Therefore, screening still retains a role in elderly patients; however, clinical judgment is still required to individualize screening practice. As the risk of competing comorbid illnesses continues to increase over time, the threshold to perform colon screening should increase accordingly.

Colonoscopy as a screening test for colorectal cancer in average-risk individuals

Screening for colorectal cancer has become the standard of care and is currently recommended by most major health organizations, including the American Cancer Society. Randomized controlled trials using fecal occult blood testing as the screening strategy have shown a reduction in mortality due to colorectal cancer. However, colorectal cancer differs from other cancers in that a variety of screening tests have been approved and recommended by experts. The advantages and disadvantages of different screening tests have been the subject of intense debate. Colonoscopy has theoretical advantages over other screening tests, including direct visualization of the entire colon and, more importantly, removal of precancerous adenomatous lesions. This review discusses the advantages and disadvantages of colonoscopy as a screening test for colorectal cancer with regard to efficacy, cost-effectiveness, and patient compliance.

Primary colonic lymphoma. Clinical presentation, histopathologic features, and outcome with combination chemotherapy

Primary colonic lymphomas are rare, but we identified 15 cases at our institution between 1973 and 1992. They comprised 5.8% of all cases of gastrointestinal lymphoma (15 of 259) and 0.16% of all cases of colon cancer (15 of 9,193) during the last 20 years. The most common presenting symptoms were abdominal pain and weight loss (40% each). In seven patients (47%), a palpable abdominal mass was noted on the initial physical examination. The most frequent site of involvement was the cecum (73%). Histologically, six (40%) were classified as high-grade and nine (60%) as intermediate-grade non-Hodgkin's lymphoma. The tumors usually presented at an advanced stage: in 13 of 15 patients (87%), the lymphoma had spread to the adjacent mesentery, the regional lymph nodes, or both when first diagnosed. The 5-year survival rate was 27% for all patients and 33% (4 of 12) for patients treated with combination chemotherapy. Two patients relapsed after 8 years of complete remission. Primary colonic lymphomas have an aggressive behavior and only a marginal response to surgery and combination chemotherapy.

Intraluminal measurement of enteric mucosal perfusion: relationship to superior mesenteric artery flow during basal and postprandial states in the dog

BACKGROUND

Several in vivo techniques that assess mucosal perfusion by intraluminal probes have recently been developed and validated, including laser Doppler flowmetry, reflectance spectrophotometry, and tonometry.

METHODS

With these techniques, a canine model where the entire vascular supply to the jejunoileum was isolated as the superior mesenteric artery and vein was used to examine the relationship between enteric mucosal blood perfusion and adjusted decrements in arterial flow under fasting and postprandial conditions.

RESULTS

Mucosal perfusion measured by laser Doppler flowmetry and reflectance spectrophotometry correlated linearly with decrements in superior mesenteric artery flow (r2 = 0.96 and 0.98, respectively); estimation of mucosal pH by tonometry decreased only after a critical level of arterial inflow was reached (less than 50% of baseline flow). Mucosal perfusion increased after the meal throughout the jejunoileum with unrestricted superior mesenteric artery flow. However, with restricted superior mesenteric artery flow, nutrient delivery to the jejunum was accompanied by increased mucosal perfusion at that level but by decreased perfusion in the distal ileum not exposed to nutrients. This latter response represents a distal to proximal redistribution of blood, i.e., an intramesenteric steal phenomenon.

CONCLUSIONS

In vivo measurements of mucosal perfusion reflected changes in large mesenteric vessel blood flow. These intraluminal techniques discriminated between a normal and an impaired mesenteric circulation in an acute model and may have clinical application.

Endoscopic laser coagulation of radiation-induced mucosal vascular lesions in the upper gastrointestinal tract and proximal colon

Endoscopic laser coagulation effectively controls bleeding from radiation-induced rectal vascular lesions.

OBJECTIVE

To assess the outcome of endoscopic treatment of radiation-induced bleeding due to vascular lesions located proximal to the sigmoid colon.

METHODS

We identified 15 consecutive patients with such proximal radiation enteropathy treated at our Institution with Nd:YAG laser between 1984 and 1991. Ten patients (66%) had gastric and/or small bowel involvement, and five (33%) had colonic involvement with or without more proximal lesions. Bleeding first appeared at a mean of 21.2 +/- 12.5 months after completion of radiotherapy. Mean duration of gastrointestinal bleeding before laser treatment was 7.6 +/- 4.6 months.

RESULTS

After completion of laser therapy, bleeding ceased in nine (60%) patients, decreased in three (20%), and persisted in three (20%). The mean hemoglobin level increased from 8.4 +/- 0.5 g/dl to 10.4 +/- 0.6 g/dl after completion of laser treatments (p < 0.02). The mean number of transfusions per patient per year decreased from 10.5 +/- 2.8 to 0.9 +/- 0.7 (p < 0.01). No treatment-related complications or deaths occurred.

CONCLUSIONS

Endoscopic laser coagulation of radiation-induced mucosal vascular lesions in the upper gastrointestinal tract and proximal colon appears to be safe and, in most cases, effective.

Endoscopic Nd:YAG laser coagulation of bleeding from radiation proctopathy

Hematochezia from mucosal vascular lesions usually confined to the rectum represents an uncommon but problematic late complication of pelvic radiotherapy. We studied 47 patients with medically refractory hematochezia resulting from radiation-induced rectosigmoid mucosal vascular lesions. All lesions were endoscopically coagulated with Nd:YAG laser. Median duration of hematochezia before laser therapy was 11 months, despite previous medical treatment (98%) or bypass colostomy (6%). Within 3 to 6 months after laser treatment, the number of patients with daily hematochezia fell from 40 (85%) to 5 (11%; p < 0.001), and the median hemoglobin level increased from 9.7 gm/dl to 11.7 gm/dl (p < 0.001). Complications occurred in three patients (6%); no deaths occurred. The condition in six patients (12.8%) was not improved by laser treatment. Two patients (4%) ultimately required surgical treatment for bleeding control. On the basis of symptomatic, hematologic, and endoscopic responses, Nd:YAG laser photocoagulation controlled bleeding from radiation proctopathy in most patients with an acceptably low morbidity. Patients with sigmoid colon involvement responded less favorably. Endoscopic laser photocoagulation should be considered before surgical intervention for treatment of hematochezia from radiation proctopathy.

The clinical and endoscopic spectrum of the watermelon stomach

The watermelon stomach is an uncommon but treatable cause of chronic gastrointestinal bleeding. We report our experience with the clinical and endoscopic features of 45 consecutive patients treated by endoscopic Nd:YAG laser coagulation. The prototypic patient was a woman (71%) with an average age of 73 years (range of 53-89 years) who presented with occult (89%) transfusion-dependent (62%) gastrointestinal bleeding over a median period of 2 years (range of 1 month to > 20 years). Autoimmune connective tissue disorders were present in 28 patients (62%), especially Raynaud's phenomena (31%) and sclerodactyly (20%). Atrophic gastritis occurred in 19 of 19 (100%) patients, with hypergastrinemia in 25 (76%) of 33 patients tested. Antral endoscopic appearances included raised or flat stripes of ectatic vascular tissue (89%) or diffusely scattered lesions (11%). Proximal gastric involvement was present in 12 patients (27%), typically in the presence of a diaphragmatic hernia. Endoscopic laser therapy after a median of one treatment (range of 1-4) resulted in complete resolution of visible disease in four patients (13%) and resolution of > 90% in 24 patients (80%). Hemoglobin levels normalized in 87% of patients over a median follow-up period of 2 years (range of 1 month to 6 years) with no major complications. Blood transfusions were not necessary after laser therapy in 86% of 28 initially transfusion-dependent patients. The characteristic clinical, laboratory, and endoscopic features allow for a confident diagnosis that can lead to successful endoscopic treatment.

Acute gastrointestinal bleeding. Experience of a specialized management team

The initial experience of a specialized management team organized to provide expedient care for all acute major gastrointestinal bleeding in protocolized fashion at a large referral center is presented. Of the 417 patients, 56% developed bleeding while hospitalized. Upper gastrointestinal bleeding accounted for 82%. The five most common etiologies included gastric ulcers (83 patients), duodenal ulcers (67 patients), erosions (41 patients), varices (35 patients), and diverticulosis (29 patients). Nonsteroidal anti-inflammatory drugs were implicated in 53% of gastroduodenal ulcers. The incidence of nonbleeding visible vessels was 42% in gastric and 54% in duodenal ulcers. The rates of rebleeding were 24% (20 patients) in gastric ulcers and 28% (19 patients) in duodenal ulcers. Predictive factors for rebleeding included copious bright red blood, active arterial streaming, spurting, or a densely adherent clot. The rebleeding rate for esophagogastric varices was 57%. The mortality rate overall was 6% (27 patients), with rates varying from 3% (five patients) for gastroduodenal ulcers to 40% (14 patients) for esophagogastric varices. The morbidity rate for the entire patient population was 18% (77 patients), dominated by myocardial events (34 patients). The average length of hospitalization for gastroduodenal ulcers was 5 days, for diverticulosis 8 days, and for varices 10 days. The major efforts of a specialized Gastrointestinal Bleeding Team would be best directed at both reducing the morbidity associated with acute bleeding and reducing the overall cost of care.

The mechanisms and prevention of intravascular fluid loss after occlusion of the supraceliac aorta in dogs

Mechanisms of intravascular fluid depletion after temporary occlusion of the supraceliac aorta were investigated in a canine model. During ischemia and reperfusion, hemodynamic parameters, superior mesenteric artery flow, intestinal mucosal perfusion, and mucosal permeability were monitored. After 12 hours of reperfusion, the volumes of intravenous electrolyte fluid required to maintain hemodynamic stability and fluid lost into the gastrointestinal tract and peritoneal cavity were measured. The distribution of total body water was analyzed by use of radionuclide dilution techniques. Group A animals underwent laparotomy only, group B had the supraceliac aorta occluded for 45 minutes, group C had superoxide dismutase administered after 45 minutes of aortic occlusion, and group D animals were exposed to mild hypothermia during a similar ischemia and reperfusion period. No significant difference was found in mean superior mesenteric artery flow or mucosal perfusion during ischemia among groups B, C, and D. During reperfusion superior mesenteric artery flow returned to values similar to control in all groups. Aortic occlusion increased mucosal permeability most significantly in group B (p less than 0.01). Mean intravenous fluid requirements (ml/mg) were the following: group A, 80 +/- 5; group B, 201 +/- 9 (p less than 0.01); group C, 116 +/- 7 (p less than 0.05); group D, 245 +/- 24 (p less than 0.05). Mean gastrointestinal fluid loss was highest in the hypothermic group and smallest if superoxide dismutase was given. Mean intracellular fluid volume was increased in groups B and D compared with group A (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Recent trends in the diagnosis and management of chronic intestinal ischemia

This paper reviews the operative management over the past 27 years of 102 patients with chronic mesenteric ischemia, and summarizes recent clinical trends and ongoing research in this area. The most important trends in the diagnosis and management of chronic intestinal ischemia include: (1) increasing use of duplex ultrasound scanning in the initial evaluation of patients with possible intestinal angina; (2) rapidly evolving noninvasive clinical tests to assess mucosal perfusion (reflectance spectrophotometry, laser Doppler flow analysis, and tonometry); and (3) preferential use of antegrade mesenteric grafts or transaortic endarterectomy for mesenteric atherosclerotic occlusive disease. Surgical revascularization continues to provide excellent early relief of symptoms (93%) and a low late recurrence rate (10%). New noninvasive diagnostic tests for chronic intestinal ischemia and excellent results of surgical revascularization support a continued aggressive approach to the early recognition and treatment of patients with chronic intestinal angina. With the aging population, we anticipate that the number of patients with chronic intestinal ischemia will increase.

Phosphaturic effect of furosemide: role of PTH and carbonic anhydrase

The first objective of this study was to examine the effects of furosemide on renal phosphate excretion in the presence and absence of a constant level of parathyroid hormone (PTH) while extracellular fluid volume was held constant. In the absence of PTH, furosemide did not significantly increase fractional phosphate excretion (FEP%, 4.2 +/- 2.7 to 6.2 +/- 1.9%; five dogs). In the presence of PTH, furosemide increased FEP% from 23.4 +/- 3.7 to 33.8 +/- 6.0% (P less .025; five dogs). Thus, the phosphaturia induced by furosemide was dependent on the presence of PTH. The second objective was to evaluate the hypothesis that furosemide exerts its phosphaturic effect through carbonic anhydrase inhibition, and therefore we tested for additivity of the phosphaturic effect of furosemide, and acetazolamide. In the presence of a constant level of PTH, acetazolamide increased FEP % from 24.5 +/- 1.8% to 40.7 +/- 5.1% P less than .025, five dogs. The subsequent administration of furosemide did not further increase FEP%, delta 3.3 +/- 8.9%; NS. Thus, the phosphaturic effect of furosemide was not additive to that of acetazolamide, indicating that acetazolamide and furosemide may share similar mechanisms for inhibiting phosphate reabsorption.