Biomedical subjects

Y Vicente

Publications and source records attributed to Y Vicente.

7 recordsLinked to original sources

PubMed2004

Demographic of short gut syndrome: increasing demand is not followed by referral of potential candidates for small bowel transplantation.

BACKGROUND: Despite improvements in small bowel transplantation (SBTx), early referral of patients with irreversible intestinal failure (IF) remains a major obstacle. In this study we evaluated the demand for SBTx among seven surgical pediatric centers located at least 200 km from our center. METHODS: From 1997 to 2001, 640 patients have been treated for neonatal diseases, including 248 who underwent a minor or major intestinal resection. Twenty-four patients with major resections presented with short gut syndrome, requiring total parenteral nutrition (TPN). The greatest demand was in postsurgical neonates with necrotizing enterocolitis, gastroschiesis, onphalocoeles, or midgut volvulus, and in three adults with postradiotherapy arteritis (n = 2) and mesenteric vein thromboses (n = 1). The median length of residual bowel after resection was 20 to 30 cm, without an ileocecal valve. Four patients were referred for SBTx evaluation; three died while awaiting a donor; 20 were not referred, among whom 14 died of TPN complications. RESULTS: Approximately 62 children per year require nutritional support for IF, most of whom develop complications related to TPN. Because many patients who are TPN-dependent develop complications, we believe that early referral would reduce mortality. CONCLUSIONS: Greater medical awareness about the feasibility of SBTx procedures and earlier referral may improve results and quality of life after transplant.

Demography↗

PubMed2001

Architecture and function of the gastroesophageal barrier in the piglet.

We describe the anatomy and function of the gastroesophageal barrier in the piglet. Male piglets underwent dissection (N = 6) and gastroesophageal muscle layer histometry (N = 6). Sedated, nonintubated animals (N = 13) underwent four-probe perfusion esophageal manometry and the pressure profiles were related to the muscular thickness in the four quadrants. Hiatal and gastroesophageal anatomy are similar to our own. The muscle is thicker at the point where the clasp (on the right side) and sling fibers (on the left) concentrate. The pressure profiles were axially and radially asymmetric in coincidence with the thickness variations of the corresponding muscle layers. Sphincteric pressure was recorded as a plateau, whereas diaphragmatic crural pressure appeared as phasic oscillations in synchrony with respiration. The sphincter relaxed upon deglutition. In conclusion, the gastroesophageal structure and physiology are so similar in men and piglets that piglets are excellent models for research in this area.

Animals↗

PubMed2001

Acute food bolus impaction without stricture in children with gastroesophageal reflux.

BACKGROUND/PURPOSE: This report identifies a group of children in whom severe acute food bolus impaction (AFBI) was the leading symptom of gastroesophageal reflux (GER) in the absence of stricture. METHODS: The esophageal structure and function of 8 patients treated for AFBI requiring endoscopic removal of alimentary foreign bodies in 6 of them (up to 4 times in 1 case) were investigated by barium meal, esophagoscopy-biopsy, pH-metering, pull-through stationary manometry, and 24-hour ambulatory manometry. The results were compared with those in a group of age-matched regular refluxers (n = 14) without AFBI. RESULTS: Six boys and 2 girls aged 108 +/- 59 months had impaction. Six children had symptoms of GER like vomiting during infancy, heartburn, or respiratory tract disease. Barium swallow ruled out stenosis in all patients and showed small hiatal hernias in 3. All had endoscopic and histologic esophagitis (moderate to severe in 6), and one had Schatzki ring. All but one (who had 8.45 mm Hg) had normal lower esophageal sphincter pressure (16.2 +/- 4.7 mm Hg, mean +/- SD), and all showed normal sphincteric relaxation. Esophageal body motility was not significantly different from that in regular refluxers except in 6 children in whom energetic distal peristalsis after reflux episodes could be seen particularly during the night. Three of them had amazingly powerful distal waves during the day and even stronger, simultaneous, wide and bizarre-shaped waves during sleep. Symptoms improved in all cases after antireflux medication. Four patients were cured after antireflux surgery. CONCLUSIONS: AFBI is a dramatic but practically unheard of symptom of GER in children. It should be differentiated from dysphagia and reveals motor dysfunction, sometimes severe, of the esophageal body in the absence of sphincteric obstruction. Antireflux medication or surgery were uniformly successful in our patients.

Acute Disease↗

PubMed2001

Esophageal motor dysfunction persists in children after surgical cure of reflux: an ambulatory manometric study.

BACKGROUND/PURPOSE: Esophageal dysmotility shown by perfusion manometry in children with gastroesophageal reflux can be primary or acquired. This study examines by combined ambulatory pH-metry and manometry the nature of motor dysfunction and whether it improves after surgical cure of reflux. METHODS: Sixteen refluxing children aged 131 +/- 54 months were studied by combined ambulatory pH-metry and manometry before and more than 6 months after successful fundoplication. pH-metric and manometric variables were compared at both time end-points by paired statistical tests accepting a significance level of P less than.05. RESULTS: Operation cured all patients clinically and pH-metrically, but, in spite of this, only the frequency of motor sequences decreased significantly after the operation from 1 (0.45) to 0.8 (0.6) waves per minute (median [interquartile range]). Wave amplitude and duration were similar in both conditions; the proportion of peristaltic waves was normal and did not change before and after the operation (79.5% [17.25] v 81.4% [21.5]; not significant), whereas the proportions of complete (63.2% [17.5] v 67.8% [19.3]; not significant) and effective (32.4% [31.95] v 27.25% [22.5]; not significant) waves were definitely low and remained so after treatment. CONCLUSIONS: The esophagus of children with GER has mild disturbances of peristaltic activity with waves often incomplete, weak, and scarcely effective. Dismotility does not improve after successful fundoplication suggesting that it could be a primary phenomenon.

Ambulatory Care↗

PubMed1996

Partial intestinal obstruction induces substantial mucosal proliferation in the pig.

Parenteral nutrition and improving supportive treatment have resulted in prolonged survival for patients with short bowel syndrome. However, definitive therapy for patients with short bowel syndrome must focus on increasing small intestinal mucosal mass. Intestinal lengthening procedures rely on intestinal dilation to accomplish this. The authors hypothesized that partial intestinal obstruction would result in consistent dilation of the intestine and would provide increased intestinal mass for use in intestinal lengthening. The authors developed a partially obstructing prosthetic valve to dilate the intestine before intestinal lengthening. This report describes the changes elicited by the valve. Twelve weanling pigs were divided randomly into two groups of six. One group had valve placement 240 cm distal to the ligament of Treitz; the other had sham surgery. The survival rate was 100% for both groups, and the mean weight gain was similar. Both groups were fed pig chow mush and were killed 5 weeks after surgery. Intestinal diameter was measured, and the small intestine was harvested, preserved, and sectioned for microscopic examination. The mean bowel diameter 15 cm proximal to the valve was 4.7 cm in the valved group and 3.3 cm in the sham group (42% increase). Total mucosal thickness, villus height, crypt depth, and villus density were significantly greater for the valved pigs in all sections (proximal and distal to the valve). Surface index and intestinal circumference were significantly greater in the valved pigs in all sections proximal to the valve, but there was no significant difference in these values for sections distal to the valve. There was no significant difference in villus cell density between the two groups at any location. Chronic partial obstruction of the small intestine results in consistent dilation of the intestine, with growth of all layers of the bowel, including the mucosa. This dilation and mucosal growth results in a true increase in surface area and is an ideal first step toward sequential lengthening.

Animals↗

PubMed1995

Comparison of open and laparoscopic gastrostomy and fundoplication in 120 patients.

The rapid development and incorporation of minimally invasive surgical techniques has abruptly changed adult surgical practices. These minimally invasive procedures are now being successfully applied to pediatric surgical problems. The anticipated benefits of these techniques include less postoperative pain, quicker return of bowel function, shorter hospital stay, and lower hospital costs, with a quicker return to normal activity. This report compares the first 60 infants and children to undergo laparoscopic gastrostomy and/or fundoplication at our institution with the same number of patients that underwent these procedures in the traditional open fashion. The two groups were similar with respect to age, sex, concurrent illness, presenting symptoms, neurological status, and procedures performed. Patients in the laparoscopic group were found to have shorter mean hospital and postoperative stays and tolerated feeding earlier. The mean hospital stay was 13.8 days for the laparoscopic group versus 16.4 days in the open group. The mean postoperative stay was 6.8 days for the laparoscopic group versus 10.7 days for the open group. The mean postoperative day on which feeding was tolerated was 2.3 in the laparoscopic group versus 4.8 in the open group. Postoperative complications were similar between the two groups. These results seem to reflect the less traumatic nature of the laparoscopic procedures as compared with the open procedures. Laparoscopic fundoplication and gastrostomy is an attractive alternative to open fundoplication and gastrostomy in infants and children.

Activities of Daily Living↗

PubMed1995

Short bowel syndrome.

Improvements in parenteral nutrition and supportive therapy have led to a growing population of patients who survive for prolonged periods with short bowel syndrome. Definitive treatment for these patients requires innovative therapy based on a sound knowledge of small intestinal physiology and adaptation. Current understanding of short bowel pathophysiology and of intestinal adaptation are reviewed. Medical and surgical therapeutic options are described, highlighting the promotion of small bowel adaptation and methods to increase the small intestinal mucosal mass.

Adaptation, Physiological↗