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Biomedical subjects

R O Dantas

Publications and source records attributed to R O Dantas.

At least 37 records · Page 2Linked to original sources
PubMed1998

Aging, esophageal motility, and gastroesophageal reflux.

OBJECTIVES: To compare esophageal motility and gastroesophageal reflux characteristics in young, middle-aged, and older healthy volunteers. DESIGN: Comparison of conventional esophageal manometry and scintigraphic study of gastroesophageal reflux in volunteers aged 20 to 30 years, 50 to 60 years, and 70 to 80 years. SETTING: Gastroenterology and nuclear medicine laboratories of a tertiary care university hospital. PARTICIPANTS: Forty healthy adult volunteers recruited from the community, 20 aged 20 to 30 years, 10 aged 50 to 60 years, and 10 aged from 70 to 80 years. MEASUREMENTS: Each volunteer underwent conventional esophageal manometry and scintigraphic study of gastroesophageal reflux. Contractile wave amplitude, duration, velocity, and lower esophageal sphincter relaxation duration, as well as the presence of abnormal peristalsis, were correlated with the proportion of volunteers with gastroesophageal reflux and the number and duration of gastroesophageal reflux episodes. RESULTS: Quantitative manometric parameters showed no correlation with gastroesophageal reflux patterns. Abnormal peristalsis was found more frequently in the older volunteers. The number of gastroesophageal reflux episodes per volunteer was similar in the three age groups, but the duration of gastroesophageal reflux episodes was longer in the older volunteers. CONCLUSION: Healthy older persons have impaired clearance of refluxed materials associated with a high incidence of defective esophageal peristalsis. This may explain the higher severity of reflux esophagitis in older people.

Adult↗
PubMed1998

Gastrointestinal manifestations of Chagas' disease.

Chagas' disease is an infectious disease that affects millions of people in Latin America and is increasingly seen outside endemic areas. A substantial number of patients develop gastrointestinal disorders secondary to lesions of the enteric nervous system. The purpose of this article is to review the current knowledge about gastrointestinal manifestations of Chagas' disease, including disorders other than the well-known gross dilations of esophagus and colon.

Bile Duct Diseases↗
PubMed1998

Gender effects on esophageal motility.

It has been suggested that there are no gender effects on esophageal motility. However, in previous studies the subjects did not perform multiple swallows and the quantitative features of esophageal contractions were not evaluated. In order to investigate the gender effects on esophageal motility we studied 40 healthy normal volunteers, 20 men aged 37 +/- 15 years (mean +/- SD), and 20 women aged 38 +/- 14 years. We used the manometric method with an eight-lumen polyvinyl catheter and continuous perfusion. The upper and lower esophageal sphincter pressures were measured by the rapid pull-through method. With the catheter positioned with one lumen opening in the lower esophageal sphincter, and the others at 5, 10 and 15 cm above the sphincter, ten swallows of a 5-ml water bolus alternated with ten dry swallows were performed. Statistical analysis was done by the Student t-test and Mann-Whitney test. Gender differences (P < 0.05) were observed for wet swallows in the duration of contractions 5 cm above the lower esophageal sphincter (men: 3.7 +/- 0.2 s, women: 4.5 +/- 0.3 s, mean +/- SEM), and in the velocity of contractions from 15 to 10 cm above the lower esophageal sphincter (men: 4.7 +/- 0.3 cm/s, women: 3.5 +/- 0.2 cm/s). There was no difference (P > 0.05) in sphincter pressure, duration and percentage of complete lower esophageal sphincter relaxation, amplitude of contractions, or in the number of failed, multipeaked and synchronous contractions. We conclude that gender may cause some differences in esophageal motility which, though of no clinical significance, should be taken into consideration when interpreting esophageal motility tests.

Adult↗
PubMed1997

Dysphagia induced by chronic ingestion of benzodiazepine.

We report a case of a 57-yr-old woman with a complaint of dysphagia of 2-wk duration. She had rheumatoid arthritis and had been taking 10 mg of prednisone and 2 mg of lorazepam daily for 2 yr. Radiologic examination showed partial retention of barium sulfate in the pharynx, which was confirmed by scintigraphic examination of the oral and pharyngeal phases of swallowing. This retention was about 47% of the volume swallowed. The benzodiazepine was withdrawn, and 2 wk later she had no symptoms. We repeated the scintigraphic study, and it showed no retention. We conclude that chronic ingestion of benzodiazepine may cause dysphagia.

Anti-Anxiety Agents↗
PubMed1996

Esophageal motility in patients with esophageal caustic injury.

OBJECTIVE: There are few studies of esophageal function subsequent to the ingestion of lye. We investigated the esophageal motility of patients who had ingested liquid sodium hydroxide. METHODS: Esophageal manometry was performed on 21 patients who [1-53 yr before the manometric examination (median: 13 yr)] had drunk 10-30 g of sodium hydroxide diluted in water. The results were compared with those obtained for a control group of 22 healthy volunteers. RESULTS: The lower esophageal sphincter (LES) pressure of the caustic group (14.9 +/- 1.7 mm Hg, mean +/- SE) did not differ (p > 0.05) from that of the control group (17.4 +/- 1.1 mm Hg). LES pressure in eight patients was below 10 mm Hg. The amplitude of contraction was lower (p < 0.01) in the caustic group than in the control group. In the proximal part of the esophageal body, the duration of contraction was longer (p < 0.01) in the caustic group (2.3 +/- 0.1 s) than in controls (1.8 +/- 0.1 s). Nonperistaltic contraction was a finding in 14 patients, repetitive in five of them. The velocity of peristaltic contractions was higher (p < 0.05) in the caustic group (distal: 3.2 +/- 0.2 cm/s) than in the control group (2.2 +/- 0.2 cm/s). Although there was some impairment of esophageal motor function in 71% of the patients, they were asymptomatic when we performed esophageal manometry. CONCLUSIONS: Esophageal motility impairment was present in most of the patients who ingested sodium hydroxide. Nonperistaltic contractions of low amplitude were found most frequently.

Accidents↗
PubMed1996

The influence of ageing on oesophageal motility after ingestion of liquids with different viscosities.

OBJECTIVES: To verify the influence of ageing on oesophageal motility elicited by the swallowing of liquids with different viscosities. DESIGN: In order to study the effect of ageing on oesophageal function, healthy volunteers of three age groups were studied by manometric and scintigraphic methods during the swallowing of water and a high viscosity liquid. METHODS: Forty healthy volunteers (20 aged 20 to 30 years, 10 aged 50 to 60 years and 10 aged 70 to 80 years) were submitted to oesophageal manometry during 10 swallows of water, 10 swallows of sugar cane syrup and 10 "dry' swallows. Basal pressure of the upper oesophageal sphincter and the lower oesophageal sphincter, amplitude, duration and velocity of contraction and the duration of the lower oesophageal sphincter relaxation were measured. Morphology and peristalsis of contractile waves were studied. The same volunteers underwent scintigraphic oesophageal transit studies with the same boluses. Oesophageal clearance time and patterns of transit were studied. RESULTS: Water and sugar cane syrup did not differ as to quantitative contraction parameters, but sugar cane syrup led to a higher incidence of synchronous contractions. The three age groups had similar amplitude and velocity of contractile waves. The youngest group had shorter duration of contractile waves 10 and 5 cm above the lower oesophageal sphincter. The oldest group had markedly more frequent synchronous contractions and failures of contraction after both water and sugar cane syrup swallows. This was associated with a high incidence of scintigraphic transit abnormalities in this group. CONCLUSION: Abnormal oesophageal peristalsis and incomplete oesophageal emptying of both low and high viscosity liquids are significantly more frequent in healthy elderly persons than in younger persons.

Adult↗
PubMed1995

Effect of isosorbide dinitrate on gastroesophageal reflux in healthy volunteers and patients with Chagas' disease.

The effect of isosorbide dinitrate (ISD) on gastroesophageal reflux and gastric emptying during the 24-min period following a liquid meal was studied in healthy volunteers, Chagas' disease patients with normal esophageal motility (CD-1 group), and Chagas' disease patients with esophageal dysmotility (CD-2 group) with dynamic scintigraphy. At random, on two separate days, the subjects received 5 mg isosorbide dinitrate or an identical-appearing placebo tablet, by the sublingual route, and ingested a liquid test meal containing [99mTc]phytate colloid before scintigraphic studies were performed. Gastroesophageal reflux episodes were more frequent (P = 0.016) and gastroesophageal reflux indexes were greater (P < 0.010) after isosorbide dinitrate than after placebo in CD-2 group (N = 15) but not in healthy volunteers (N = 14) or CD-1 group (N = 9); six of seven CD-2 patients presenting with gastroesophageal reflux after isosorbide dinitrate had abnormal clearance of refluxate. Gastric emptying was similar in healthy volunteers (N = 13), CD-1 patients (N = 6), and CD-2 patients (N = 13), and no effect of isosorbide dinitrate on it was detected in any of the groups. In separate studies, 5 mg isosorbide dinitrate reduced the lower esophageal pressure (P < 0.01) in seven CD-2 patients. These results indicate that ISD increases the tendency towards GER in CD-2 patients, but not in healthy volunteers or CD-1 patients. This effect is probably related to an exceedingly intense relaxation of the LES caused by ISD in CD-2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Esophageal origin of precordial pain in chagasic patients with normal subepicardial coronary arteries].

PURPOSE: To study the chest pain of esophageal origin in chagasic patients (CH) and non-chagasic subjects (NCH) with normal coronary arteries. METHODS: The study comprised 48 patients: 33 CH (age 56 years, 50% male) and 15 NCH (age 47 years, 25 male), with precordial chest pain and normal subepicardial coronary arteries. They were assigned to upper digestive tract radiologic and endoscopic study, esophageal manometric evaluation at baseline and after provocative tests (Bernstein and intravenous edrophonium). RESULTS: Radiologic study: 14 (42%) CH and 4 (27%) NCH had esophageal dilation (p > 0.05). Hiatal hernia was documented in 7 (21%) CH and 6 (40%) NCH (p > 0.05). 2) Digestive endoscopy: In 15 (45%) CH and 6 (40%) NCH distal esophagitis were seen. In the NCH, esophagitis occurred with hiatal hernia; however only 30% of CH with esophagitis had also hiatal hernia while another 30% had esophageal dilation. 3) Esophageal motility disorders (EMD): 11 (33%) CH showed EMD: 8 with inferior esophageal sphincter achalasia (IESA) and 3 with diffuse esophageal spasm. Among NCH, 2 (13%) had IESA (p > 0.05). 4) Bernstein test--a positive test was seen in 5 (15%) CH and 3 (20%) NCH-p > 0.05. CH with esophageal dilation had 14% of positive results, while CH without esophageal dilation had 16%-p > 0.05. 5) Intravenous edrophonium-esophageal contraction amplitude enhancement provoked by the drug infusion was clearly attenuated in the chagasic (6.9 +/- 12.7 mmHg) when compared with the NCH group (18.8 +/- 21.4 mmHg). A positive test (i.e. chest pain) was obtained in only one patient who was NCH. CONCLUSION: Esophageal pain could be elicited at a relatively low and comparable rate in both groups of patients.

Adult↗
PubMed1995

The spectrum of esophageal motor disorders in Chagas' disease.

OBJECTIVE: To determine the patterns of esophageal motility found in patients with Chagas' disease. METHODS: Clinical, manometric, and scintigraphic data were obtained from 43 subjects with positive serological tests for Chagas' disease and nondilated esophagus and 10 patients with Chagasic megaesophagus. RESULTS: Twenty (46.5%) of the seropositive subjects with nondilated esophagus were asymptomatic, and 23 (53.5%) had dysphagia, but only 12 (27.9%) had persistent dysphagia, a feature typical of Chagasic megaesophagus; only two (4.6%) had chest pain. Manometric findings within the seropositive group were: normal motility in 16 subjects, peristaltic multipeaked contractions in three, aperistalsis of the esophagus with relaxing lower esophageal sphincter in nine, and aperistalsis with nonrelaxing lower esophageal sphincter in 15 subjects. All of 10 megaesophagus patients had aperistalsis of the esophagus plus nonrelaxing lower esophageal sphincter. Scintigraphy was as sensitive as manometry in detecting esophageal dysmotility, but the erect scintigraphy was abnormal in subjects with complete aperistalsis only. CONCLUSION: In Chagas' disease, megaesophagus appears to be a disorder at the most severe end of a spectrum encompassing classical achalasia and its milder variants. Other esophageal motility disorders are rare, but normal esophageal function is common.

Adolescent↗
PubMed1994

Comparison of methods for recording esophageal sphincter pressures in Chagas' disease.

We measured the lower (LES) and upper esophageal sphincter (UES) pressure in 22 Chagas' disease patients with dysphagia and abnormal radiologic esophageal examination, and in 12 normal volunteers. We compared the station pull-through (SPT) and rapid-through (RPT) techniques of sphincter pressure measurement, using an infused round catheter 5 mm in outer diameter, and with four side orifices at the same level. The LES pressure was higher when measured by RPT than by SPT and at inspiration than expiration (P/0.05). In Chagas' disease patients, LES pressure was lower than in volunteers, with significance when measured by RPT at expiration (P/0.05). In normal volunteers, but not in patients, the UES pressure was higher when measured by RPT at expiration than when measured by SPT. When measured by RPT the UES pressure of Chagas' disease patients was lower than in volunteers. In conclusion, LES pressure was higher when measured at inspiration and by the RPT technique. There was a considerable overlap of LES individual pressures between patients and volunteers, but the pressure was lower in patients when we used RPT at expiration. In normal volunteers the RPT technique recorded higher UES pressures than the SPT, and higher pressures than in Chagas' disease patients.

Adult↗
PubMed1993

Esophageal motility impairment in Plummer-Vinson syndrome. Correction by iron treatment.

We report the case of a 41-year-old woman with Plummer-Vinson syndrome and an esophageal motility disorder. She complained of dysphagia and odynophagia and had cheilitis, glossitis, and hypochromic anemia. An esophageal motility study showed low amplitude of contraction and high intrabolus pressure in the esophageal body. After iron replacement, the patient was free from symptoms, and a new motility study showed increased amplitude of contraction and decreased intrabolus pressure.

Adult↗
PubMed1993

Esophageal dysfunction does not always worsen in systemic sclerosis.

Using the manometric method, we studied the progression of esophageal involvement in 17 women with a diagnosis of systemic sclerosis (SSc) and compared the results with those obtained for 14 healthy women. The manometric examination of SSc patients was performed twice, with an interval of 9 to 111 months (median, 40 months). All patients had peristaltic contractions in the proximal esophagus. Eight had peristaltic contractions, and 9 had no contraction in the middle and distal esophagus. The lower esophageal sphincter pressure and the amplitude of contractions in the esophageal body were lower in SSc patients than in controls. The duration of contractions was the same in SSc patients and controls. The velocity of peristaltic contractions did not differ between patients and controls in the distal esophagus, but was higher in SSc patients in the proximal esophagus. In 16 patients, no difference in lower esophageal sphincter (LES) pressure, esophageal contraction amplitude, duration, and velocity was observed between the first and second evaluation. In one patient, the distal esophageal contractions changed from peristaltic to completely absent, and the lower esophageal sphincter pressure changed from 20.2 mm Hg to 5.1 mm Hg. The results suggest that the esophageal involvement of SSc patients was not progressive in all cases.

Adolescent↗
PubMed1992

Alteration of the upper esophageal sphincter belch reflex in patients with achalasia.

Some patients with achalasia have been reported to develop airway obstruction from a massively air-distended esophagus, which may represent an abnormality in the upper esophageal sphincter belch reflex. When questioned carefully, 95% of our achalasia patients reported difficulty with belching. The upper esophageal belch reflex in 23 consecutive achalasia patients and 12 healthy controls was studied using an upper esophageal sphincter sleeve manometry catheter and rapid injection of 20-50 mL of air into the midesophagus. Compared with normal subjects, achalasia patients were significantly less likely to have an esophageal belch for all volumes tested and were more likely to have an increase rather than a decrease in upper esophageal sphincter pressure in response to air injection. This study systematically documents that many achalasia patients have an alteration in the upper esophageal sphincter belch reflex that may be a contributory mechanism for some of the chest and upper airway symptoms reported by some patients during acute esophageal distension.

Adolescent↗
PubMed1992

Diaphragmatic contribution to gastroesophageal competence and reflux in dogs.

Events associated with gastroesophageal reflux have been determined by concurrent diaphragmatic and esophageal body electromyography, video radiography, and manometry in four conscious dogs. Three characteristic phenomena occurred in parallel immediately before and during gastroesophageal reflux: 1) transient lower esophageal sphincter relaxation, 2) profound (99.5%) and selective inhibition of crural diaphragmatic activity, and 3) a previously unrecognized dorsal movement of the gastroesophageal junction (mean 1.3 cm) demonstrated by implanted radiological markers. The patterns associated with spontaneous acid and gas reflux were indistinguishable from those induced by gastric distension. Costolumbar diaphragmatic activity was stable up until the instant of sphincter opening, when there was a single costolumbar contraction of short duration and high amplitude. Esophageal shortening did not occur before reflux. Reflux that occurred after atropine-induced inhibition of lower esophageal sphincter tone to < 2 mmHg was intermittent and coincided with selective crural inhibition. These studies demonstrated that selective crural inhibition is a prerequisite for gastroesophageal reflux and suggest that the crural diaphragm is an important factor for the maintenance of gastroesophageal competence.

Animals↗
PubMed1991

Videoradiographic, manometric, and electromyographic analysis of canine upper esophageal sphincter.

We assessed upper esophageal sphincter (UES) function in dogs by concurrent recording of cricopharyngeal electromyographic (EMG) activity, intraluminal pressure, and dimensional changes of the pharyngoesophageal junction at rest and during swallowing. Radial and axial pressure profiles of the UES were determined by continuous pull-through manometry. EMG activity of the cricopharyngeus and thyropharyngeus muscles were correlated with UES pressure under static conditions. We also quantified the temporal relationships among EMG activity of the cricopharyngeus, UES pressure, and pharyngoesophageal junction dimensional changes during swallowing of 2, 4, and 6 ml of barium. When the dogs were prone, the anterior and posterior UES pressures were about twice the lateral pressures and the axial length of the UES was approximately 4 cm. All radial pressures equalized to approximately 20 mmHg when the dogs lay on their sides. The peak pressure zone of the UES corresponded closely with the level of the cricopharyngeal electrode, and resting UES pressure correlated closely with cricopharyngeal but not thyropharyngeal EMG activity. During swallowing, the cricopharyngeus relaxed approximately 200 ms before UES opening and 100 ms before UES relaxation. Superior movement of the hyoid and the larynx was associated temporally with UES relaxation, while anterior movement was associated with UES opening. Increases in bolus volume significantly increased maximal sagittal UES diameter during UES opening but did not alter temporal changes in UES function.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Effect of increased intra-abdominal pressure on peristalsis in feline esophagus.

Our aim in this study was to determine the effect of variations in intrabolus pressure on esophageal peristalsis. In five cats, intrabolus pressure was altered by increasing intragastric pressure to 20-45 mmHg by use of a pressure cuff to compress the abdomen. In each cat, increases in intragastric pressure were associated with comparable increases in pressure of the esophageal bolus while the bolus was in the distal esophagus during esophageal peristalsis. Secondary peristalsis induced by a 5-ml injection of barium into the proximal esophagus was recorded by synchronized videofluoroscopy and esophageal manometry. Graded increases in intrabolus pressure caused an increased prevalence of ineffective, incomplete peristaltic sequences that did not completely clear barium from the esophagus. At intragastric pressures greater than 45 mmHg, 63% of the peristaltic sequences were incomplete. Increases in intrabolus pressure elicited by increased intragastric pressure also caused 1) slowing of the peristaltic wave in the distal esophagus, 2) increased pressure wave duration in the distal esophagus, 3) increased esophageal diameter, and 4) increased duration of lower esophageal sphincter opening. The incidence of retrograde bolus escape was inversely related to the difference between peristaltic wave amplitude and intrabolus pressure. A pressure difference of greater than 20 mmHg prevented retrograde barium escape at all esophageal levels, whereas a difference of less than 20 mmHg was generally associated with retrograde escape of barium in the distal esophagus. We conclude that an increase in intrabolus pressure causes an increase in esophageal distension that is transduced into alterations of esophageal peristalsis by either a myogenic or neural mechanism.

Abdomen↗
PubMed1990

Manometric characteristics of glossopalatal sphincter.

When a liquid bolus is held in the mouth, the posterior tongue and soft palate pinch together to prevent premature spillage of the bolus into the oropharynx. We propose that this glossopalatal closure acts as a glossopalatal sphincter (GPS). In this investigation, we studied glossopalatal closure by obtaining concurrent manometric and radiographic recordings of barium swallows in healthy volunteers. Manometry was done by both a continuous pull through method and also by a stationary catheter technique using a ribbon catheter with multiple sideholes spaced at 1-cm intervals. The results showed that when the mouth was loaded with a fluid bolus, the closed glossopalatal segment generated an asymmetric high-pressure zone with greater pressures toward the tongue and palate than laterally. With swallowing, the glossopalatal sphincter high-pressure zone relaxed and the glossopalatal sphincter opened to allow barium to flow from the mouth into the oropharynx. We conclude that the glossopalatal sphincter functions as a physiological sphincter in that it (1) generates a sustained high-pressure zone and closure when a liquid bolus is held in the mouth and (2) relaxes and opens with swallowing.

Adolescent↗