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N T Welch

Publications and source records attributed to N T Welch.

12 recordsLinked to original sources

Surveillance for Barrett's oesophagus in the UK.

BACKGROUND: Endoscopic screening for Barrett's oesophagus is being offered without evidence of efficacy Barrett's oesophagus is not an ideal candidate for a screening programme, as the natural history is unclear, uncertainties surround the indication for intervention and the treatment is associated with high morbidity and mortality rates. METHODS: To determine the practices that clinicians employ in the management of Barrett's oesophagus in the UK, postal questionnaires were sent in May 1997 to 297 randomly selected members of the British Society of Gastroenterology asking for details of their current practice. RESULTS: Of 152 respondents, 106 (70 per cent) performed surveillance for Barrett's oesophagus; 46 (30 per cent) did not carry out screening. There was no difference in the practices carried out by physicians or surgeons, teaching or acute general hospital clinicians, or those with an upper gastrointestinal interest. There was a wide disparity in screening interval: just over half (52 per cent) screen at yearly intervals. Only nine (8 per cent) took four quadrant biopsies per 2 cm of Barrett's oesophagus. Nearly half (49 per cent) manage mild dysplasia by increasing the frequency of endoscopy; only seven (7 per cent) prescribed patients a proton pump inhibiting agent. Faced with severe dysplasia, 33 (31 per cent) offered surgery immediately; 22 (21 per cent) simply followed the patient by endoscopy. Those not choosing to perform screening most frequently cited lack of evidence of efficacy as the reason behind their decision. CONCLUSION: There is wide variation in surveillance practices for Barrett's oesophagus. Some methods are ineffectual. The recommendations made by the Barrett's Oesophagus Working Party in 1991 are not followed, possibly because they are not practical. New workable guidelines based on available evidence and a consensus of expert opinion should be established; this was suggested by 38 per cent of respondents who performed screening.

Barrett Esophagus

Abnormal plasma gut hormones in pathologic duodenogastric reflux and their response to surgery.

Fasting and postprandial plasma levels of the gut hormones gastrin, cholecystokinin (CCK), secretin, glucose-dependent insulinotropic polypeptide, motilin, neurotensin, peptide YY (PYY), enteroglucagon, glucagon, insulin, and pancreatic polypeptide were measured in 11 patients with alkaline gastritis associated with excessive duodenogastric reflux not related to previous gastric surgery (primary DGR), 12 primary DGR patients after pancreatico-biliary diversion ("duodenal switch" procedure), and in 10 age-matched healthy controls. Gastric emptying of a semisolid oatmeal was also measured in patients with primary DGR and in patients after bile diversion. Fasting plasma levels of the distal gut hormone neurotensin and the pancreatic islet hormone insulin were significantly greater in patients with primary DGR compared with controls. Neurotensin levels were normal in patients studied after bile diversion. Postprandial plasma levels, incremental integrated and total integrated responses for CCK, secretin, insulin, neurotensin, PYY, and enteroglucagon, were significantly greater in patients with primary DGR compared with controls. The majority of these responses normalized after bile diversion; however, the postprandial response for insulin and enteroglucagon remained elevated. Patients with primary DGR had a rapid early postprandial phase of gastric emptying of solids, which showed a significant correlation with plasma neurotensin levels. Bile diversion produced a significant delay in this lag-phase of gastric emptying. These abnormalities in gut regulatory hormones appear to be adaptive changes to rapid early postprandial gastric emptying, probably related to antropyloric dysmotility, which has been implicated in the pathogenesis of this condition. Measurement of these gastrointestinal hormones may become useful in the diagnosis of primary DGR.

Anastomosis, Roux-en-Y

Comparison of an intravenous bolus of famotidine and Mylanta II for the control of gastric pH in critically ill patients.

The effects of the intravenous bolus administration of famotidine versus the administration of Mylanta II liquid every 2 hours on the pH of the gastric antrum, body, and fundus for 24 hours were compared in 10 critically ill patients admitted to the intensive care unit with isolated cranial trauma. Patients received 30 mL of Mylanta II every 2 hours via nasogastric tube for 24 hours, followed by administration of 20 mg of intravenous bolus famotidine every 12 hours for the subsequent 24-hour period. pH of the gastric antrum, body, and fundus was monitored continuously using a three antimony pH electrode/nasogastric tube assembly. Gastric pH data were analyzed for the percentage of time pH was less than 4 and median pH for the antrum, body, and fundus for each 24-hour period. The percentage of time pH was less than 4 was significantly less in the antrum and body of the stomach during famotidine therapy (8.9% +/- 3.6% and 24.9% +/- 6.9%, respectively) compared with Mylanta II (39.1% +/- 6.7% and 57.6% +/- 8.5%, respectively, both p < 0.005), but was not significantly different in the fundus (famotidine: 25.3% +/- 7.8%; Mylanta II: 28.3% +/- 6.5%). Median gastric pH for 24 hours was significantly greater in the antrum and body of the stomach during famotidine therapy (7.8 +/- 0.2 and 6.8 +/- 0.6, respectively) compared with Mylanta II (4.5 +/- 0.6 and 3.7 +/- 0.9, respectively, p < 0.005 and p < 0.01, respectively), but was not significantly different in the fundus (famotidine: 5.9 +/- 0.8; Mylanta II: 5.4 +/- 0.7). The data indicate that an intravenous bolus of famotidine every 12 hours is more effective than Mylanta II liquid every 2 hours administered via a nasogastric tube in maintaining gastric pH above 4 in critically ill patients. Famotidine produces a uniform increase in gastric pH throughout the stomach, whereas Mylanta II controls only proximal gastric pH, probably related to fundic pooling of antacid in the supine position.

Adult

Effect of duodenal switch procedure on gastric acid production, intragastric pH, gastric emptying, and gastrointestinal hormones.

The duodenal switch operation preserves the pylorus and the proximal 3 to 7 cm of duodenum in continuity with the stomach while diverting pancreaticobiliary secretions. We compared it with the Roux-en-Y without vagotomy or antrectomy in 12 dogs with innervated gastric pouches. Acid secretion was inhibited between tests using ranitidine in the Roux-en-Y group only, but two of the six dogs still developed stomal ulcers and the remainder showed stomal hyperemia. This may be due to a significant increase in gastric acid output after Roux-en-Y, but gastric emptying and plasma gastrin, cholecystokinin, secretin, gastric inhibitory polypeptide, peptide YY, and neurotensin were similar after both procedures. In 12 patients and a further 6 dogs, the duodenal switch caused no significant change in the intragastric pH environment as assessed by intragastric pH monitoring. The duodenal switch is a suitable procedure for pancreaticobiliary diversion.

Anastomosis, Roux-en-Y

Laparoscopic capture of "escaped" gallstones.

Difficulties can be experienced trying to retrieve gallstones during laparoscopic cholecystectomy. We present three cases and describe three techniques to securely grasp large, free peritoneal calculi. The need to recover such stones is discussed.

Adult

Laparoscopic incidental appendectomy.

The benefits and risks of laparoscopic incidental appendectomy are discussed. We believe a case for laparoscopic incidental appendectomy can be made for patients undergoing diagnostic laparoscopy for lower abdominal pain in whom either no cause is found, or in whom a cause other than appendicitis is discovered. No benefit from incidental appendectomy can be shown for patients undergoing laparoscopy for other disorders.

Abdominal Pain

Beware of the porcelain gallbladder during laparoscopic cholecystectomy.

Technical problems of retraction and hemorrhage during laparoscopic removal of a porcelain gallbladder are described. Although laparoscopic cholecystectomy was successful, a blood transfusion was required. We believe that porcelain gallbladder is a relative contraindication to laparoscopic cholecystectomy. The merits of plain radiography, computed tomography, and ultrasound in making the diagnosis are also discussed.

Blood Loss, Surgical