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K R DeVault

Publications and source records attributed to K R DeVault.

49 records · Page 3Linked to original sources
PubMed1994

Intraesophageal balloon distention in the evaluation of sensory thresholds: studies on reproducibility and comparison of balloon composition.

OBJECTIVE: Graded intraesophageal balloon distention has been suggested as a provocative test in the assessment of undetermined chest pain. Balloon distention was used to determine pain threshold reproducibility for 20 normal individuals (mean age: 27 yr). METHODS: Balloons made of silicone and latex were each evaluated in 10 subjects, with the balloon located 10 cm above the lower esophageal sphincter. The balloons were sequentially inflated with 2-cc increments of air by a specially designed pump to a total volume of 2 cc above the level of pain for each subject. A random series of inflations was also used. Three sets of both sequential (S) and random (R) inflations were performed on 2 subsequent days. RESULTS: With the silicone balloon, the mean volume for pain threshold was 15 +/- 1.1 cc (+/- SE) for S and 15 +/- 1.2 cc for R inflations on day 1 and 15 +/- 1.5 cc and 15 +/- 1.5 cc on day 2. For the latex balloons, the mean volume for pain threshold was 17 +/- 1.4 cc for S and 17 +/- 1.4 cc for R inflations on day 1 and 17 +/- 1.6 cc and 18 +/- 1.9 cc on day 2. CONCLUSION: From these studies, we conclude that pain thresholds to esophageal balloon distention are reproducible with same or subsequent day testing. Similar effects occur with either silicone or latex balloons. In vitro studies on the inflation characteristics of the balloons indicate that the latex balloon inflates in a more even, linear manner, which makes this balloon more practical for evaluating pain thresholds in terms of air volume inflations.

Adult↗
PubMed1993

Cerebral evoked potentials. A method of quantification of central nervous system response to esophageal pain.

Cerebral evoked potentials (EPs) represent a new technique for the evaluation of afferent outflow from the gastrointestinal tract. We compared EPs obtained with distension of the distal and proximal esophagus. Responses were recorded with the balloon 5 cm proximal to the lower esophageal sphincter and 3 cm distal to the upper esophageal sphincter. Balloon stimulation resulted in cortical responses recorded by midline scalp electrodes (CZ', PZ, and OZ by the International 10-20 system) in normal volunteers. EP responses consisted of two negative (N1, N2) and one positive (P1) deflections. The proximal esophageal latency of N1 was shorter in all three leads. The latency to P1 was shorter with proximal stimulation in lead CZ' only, and N2 latencies were not different. Amplitudes expressed as the difference between N1 and P1, and P1 and N2 were not different. When two sets of potentials several minutes apart from the proximal position were compared, a decrease in amplitude with the second set of stimulations was noted. Esophageal EP recording is a new technique that may provide information about the integrity and function of the sensory innervation of the esophagus.

Adult↗
PubMed1993

Salivary stimulation mimics esophageal exposure to refluxed duodenal contents.

It has been suggested that shifts in gastric and esophageal pH can be used to estimate the reflux of injurious alkaline material, particularly bile, into the esophagus. We sought to evaluate the contribution of swallowed saliva to alkalinization of both the stomach and esophagus in 10 normal volunteers, by performing combined gastric and esophageal pH monitoring before, during, and after salivary stimulation. The intraesophageal pH universally increased during salivary stimulation, whereas the intragastric pH was noted to increase in six of 10 subjects. In four of these six, the pattern of simultaneous increases in esophageal and gastric pH mimicked and could be mistaken for episodes of "alkaline reflux." We conclude that the diagnosis of reflux of duodenal contents into the esophagus by pH monitoring may be compromised by false-positive results related to swallowed saliva.

Adult↗
PubMed1992

Esophageal balloon distention and cerebral evoked potential recording in the evaluation of unexplained chest pain.

A minority of patients presenting with the common clinical challenge of unexplained chest pain can be diagnosed as having an esophageal etiology for their pain using conventional manometric and provocative (acid infusion and edrophonium) testing. Esophageal balloon distention may provide an important adjuvant to routine testing. Most pain from the esophagus is mediated by visceral sensory receptors located near the myenteric plexus; these receptors respond to movements of the organ wall in response to contractions or distention. Balloon distention can be used to simulate this wall movement. Early clinical studies have been expanded by recent investigations demonstrating a lowered pain threshold in response to balloon distention in patients with both unexplained chest pain and nonobstructive dysphagia. The physiologic basis for this increased sensitivity is not clear. Balloon distention has several effects on esophageal motility that may play a role in producing pain. The recording of cerebral evoked potentials is a technique newly developed to provide an objective measurement of the subjective sensation of pain. Electrical and mechanical stimulation of the esophagus has been shown to produce cerebral evoked potentials. Recent investigations of cerebral potentials evoked by balloon-induced esophageal stimulation have confirmed that this response depends on pain production, have clarified the appropriate stimulus parameters, and have localized the site of origin of the evoked potential to the balloon site. Balloon distention may prove to be an important addition to current esophageal provocative testing, although widespread applicability has been hampered by the lack of a commercially available standardized balloon. Recording evoked potentials produced by esophageal stimulation may provide additional clues in unraveling the mystery of unexplained chest pain.

Brain↗
PubMed1992

Acute esophageal hemorrhage from a vagal neurilemoma.

A man with known systemic neurofibromatosis developed an acute upper gastrointestinal hemorrhage while hospitalized after a neurosurgical procedure. Endoscopic evaluation showed a vascular lesion with an appearance consistent with a Dieulafoy-type lesion in the distal esophagus. Despite multiple endoscopic procedures with attempted coagulation of the bleeding lesion, the patient continued to have life-threatening hemorrhaging. At thoractomy, a tumor was found to arise from the vagus nerve at the site of bleeding. This tumor was resected and histologically determined to be a neurilemoma. Acute bleeding into the esophagus associated with this type of tumor has not been previously reported.

Cranial Nerve Neoplasms↗
PubMed1987

Effects of antireflux therapies on salivary function in normal humans.

Saliva has received recent attention because of its potential role in esophageal clearance and neutralization of refluxed gastric contents. Gastric antisecretory drugs or promotility drugs used to treat reflux have not been studied for their ability to affect salivary function. We conducted a double-blind randomized study of four antisecretory drugs, two promotility drugs, and placebo (PL) on 12 healthy volunteers on seven different days. Following a 6-hr fast, accumulated saliva was expectorated at least once per minute. The initial 10-min sample was discarded and a baseline 20-min sample collected. One of the following was given per os: PL, pirenzepine (PIR), 50 mg; propantheline (PRO), 30 mg; cimetidine (CIM), 300 mg; ranitidine (RAN), 150 mg; bethanechol (BET), 25 mg; or metoclopramide (MET), 10 mg. Saliva was collected for 60 min. Saliva was then stimulated (STIM) by sucking a peppermint lozenge for 30 min. Specimens were collected under oil, kept on ice, and analyzed within 30 min. Saliva flow in milliliters per minute and capacity for acid neutralization (CAN) in microequivalents acid per milliliter saliva were analyzed on all samples. The known effect of PRO to inhibit both basal saliva flow and STIM flow and CAN was seen. In contrast, the selective antimuscarinic PIR did not significantly decrease saliva flow or CAN. CIM, RAN, and MET did not significantly effect salivary function, but both CIM and RAN showed a tendency to increase CAN. Oral BET had no detectable effect on salivary function.

Adult↗
PubMedDate not supplied

Ingested foreign bodies within the appendix: A 100-year review of the literature.

BACKGROUND/AIM: Appendicitis and its complications remain a common problem affecting patients of all age groups. Foreign bodies are a rare cause of appendicitis. We tried to define potentially dangerous foreign bodies that may cause appendicitis and summarize general guidelines for their clinical management. METHODS: A 100-year literature review including 256 cases of ingested foreign bodies within the appendix with emphasis on: (1) objects that are more prone to cause appendicitis or appendiceal perforation; (2) foreign bodies that are radiopaque and may be detected during follow-up with plain abdominal films, and (3) guidelines for clinical management. RESULTS: Complications usually occur with sharp, thin, stiff, pointed and long objects. The majority of these objects are radiopaque. An immediate attempt should be made to remove a risky object by gastroscopy. If this fails, clinical follow-up with serial abdominal radiographs should be obtained. If the anatomical position of the object appears not to change and, most commonly, remains in the right lower abdominal quadrant, an attempt at colonoscopic removal is indicated. If this is unsuccessful, laparoscopic exploration with fluoroscopic guidance should be carried out to localize and remove the objects either by ileotomy, colotomy, or by appendectomy. CONCLUSION: Foreign bodies causing appendicitis are rare. However, if stiff or pointed objects get into the appendiceal lumen they have a high risk for appendicitis or perforation. These foreign bodies are almost always radiopaque.

Appendicitis↗
PubMedDate not supplied

Epidemiology and significance of Barrett's esophagus.

Barrett's esophagus (BE) is of interest because of its recognized association with esophageal adenocarcinoma. While BE develops in a minority of patients with gastroesophageal reflux disease, its diagnosis has markedly increased over the last 30 years. Although a concurrent increase in the number of endoscopies performed annually has improved the ability to diagnose BE, the increase in prevalence appears to be a true finding. Conflicting data in the literature confound an accurate assessment of the risk for adenocarcinoma in patients with BE. Certain factors associated with BE also hold for esophageal adenocarcinoma: greater severity of reflux symptoms, specific pattern of symptoms (particularly nocturnal), longer duration of symptoms, white race, and male gender. One report has suggested a 45-fold increase in cancer risk for patients with frequent, severe and long-standing heartburn symptoms. New cases of esophageal adenocarcinoma are also increasing, especially in white males, with over 6,000 new cases diagnosed in 1995. BE can progress to esophageal dysplasia and adenocarcinoma; hence, early diagnosis and surveillance of BE and treatment of high-grade dysplasia leads to improved survival. The reported risk of developing cancer in BE ranges from 0.4 to 1.9%/year of follow-up. Most recent studies have tended to report rates of 0.5%/year or lower. Despite these data and concerns, at least two actuarial studies have suggested that the risk of death in patients with BE does not differ from that of a control population. This review of the literature focuses on the epidemiology of BE and the associated incidence of its sequelae.

Adenocarcinoma↗
PubMedDate not supplied

What is the optimal medical therapy for Barrett's esophagus?

The development of Barrett's esophagus (BE) in patients with gastroesophageal reflux disease (GERD) is troubling because of its known association with esophageal cancer. When evaluated clinically, patients with BE have the severest form of GERD and require aggressive therapy to control esophageal acid exposure. Both hypotension of the lower esophageal sphincter and the extent of esophageal acid exposure are major contributors to severe GERD and its complications. It is hypothesized that better control of acid will improve outcomes for BE patients. While it is clear that therapy (medical or surgical) for reflux rarely if ever results in total regression of BE, there are some limited data to support improvement in BE with control of reflux. Current medical choices include prokinetic agents, histamine type-2 receptor antagonists, and proton pump inhibitors. In the future, genetic markers may be used in identifying BE patients at the greatest risk for histologic progression, and chemoprevention with cyclooxygenase-2 inhibitors may be a therapeutic option. This paper will review the rationale for and results of medical antireflux therapy in patients with BE.

Anti-Ulcer Agents↗
PubMedDate not supplied

Lower esophageal (Schatzki's) ring: pathogenesis, diagnosis and therapy.

Schatzki's or lower esophageal ring (LER) is one of the most common causes of solid food dysphagia. These rings are associated with hiatal hernias and appear to be produced by an infolding at the junction between the squamous and columnar mucosa. The pathogenesis of LER is not clear, but may be related to gastroesophageal reflux disease (GERD), while GERD and pill injury may worsen the dysphagia associated with LER. LERs are best diagnosed with a combination of history and a carefully performed barium esophogram with solid bolus challenge. Therapy includes instruction in slow and careful mastication. Bougienage is the main form of treatment, but selected patients may require pneumatic dilation, electrosurgical techniques or surgical repair. GERD should be treated if present in these patients.

Deglutition Disorders↗