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Is delayed gastric emptying following pancreaticoduodenectomy related to pylorus preservation?

BACKGROUND: Delayed gastric emptying (DGE) is the most frequent postoperative complication after pylorus-preserving pancreaticoduodenectomy (PPPD). This prospective, non-randomized study was undertaken to determine whether the incidence of DGE may be reduced by modifying the original reconstructive anatomy with a retrocolic duodenojejunostomy towards an antecolic duodenojejunostomy. PATIENTS AND METHODS: The study was comprised of 51 patients who underwent PPPD between August 1994 and November 1997. The operation was carried out as originally described but was modified by performing the duodenojejunostomy antecolically. Clinical data were recorded prospectively, with special regard to DGE. RESULTS: After PPPD, the nasogastric tube could be removed at a median of 2 days (range 1-22 days) postoperatively; in two patients, the nasogastric tube was reinserted because of vomiting and nausea. A liquid diet was started at a median of 5 days (3-11 days); the patients were able to tolerate a full, regular diet at a median of 10 days (7-28 days). The overall incidence of DGE was 12% (n=6). No postoperative complications other than DGE were exhibited by 36 patients (71%). In this group, DGE was only seen in one patient (3%). In the second group, where postoperative complications other than DGE occurred (n=15), five patients (30%) exhibited DGE (P=0.002). CONCLUSIONS: DGE after PPPD seems to be of minor clinical importance following uncomplicated surgery. When taking the results into consideration, it can be said that, despite the lack of a control group, antecolic duodenojejunostomy might be the key to a low incidence of DGE after PPPD. In our experience, DGE is linked to the occurrence of other postoperative complications rather than to pylorus preservation.

Female↗

Gastric motility after laparoscopically assisted distal gastrectomy, with or without preservation of the pylorus, for early gastric cancer, as assessed by digital dynamic x-ray imaging.

This study aimed to evaluate the usefulness of digital x-ray imaging for measuring gastric motility in patients subjected to laparoscopically assisted distal gastrectomy without preservation of the pylorus (LADG) or laparoscopically assisted pylorus-preserving gastrectomy (LAPPG) for early gastric cancer. Between April 1998 and February 2002, 52 patients with preoperative stage IA gastric cancer underwent laparoscopically assisted distal gastrectomy, with 26 receiving LADG for tumors in the lower third of the stomach and 26 receiving LAPPG for tumors in the middle third of the stomach. The gastric emptying ratio at 15 min after the ingestion of the test meal was 61.8% +/- 28.0% for LADG and 42.9% +/- 18.0% for LAPPG ( p < 0.01). The motility index was 2.65% +/- 2.54% for LADG and 8.13% +/- 2.46% for LAPPG ( p < 0.001). In conclusion, LAPPG results in better motility than LADG for patients with early gastric cancer arising in the middle third of the stomach.

Adult↗

Laparoscopically assisted pylorus-preserving gastrectomy.

BACKGROUND: The aim of this study was to describe the procedure of laparoscopically assisted pylorus-preserving gastrectomy (LAPPG), and to evaluate intra- and postoperative conditions of the patients. METHODS: We performed pylorus-preserving gastrectomy under laparoscopic observation, including regional lymph node dissection in early gastric cancer of the lower body. Seven patients were treated (two women and five men) using this procedure between April 1996 and April 1999. RESULTS: All the patients showed good postoperative recovery, and no signs of recurrence were recognized. There were no intraoperative or postoperative complications. Less pain, a rapid recovery, and good cosmetic results were noted. The patients exhibited little weight loss after surgery, and none demonstrated the dumping syndrome. Endoscopic examinations performed postoperatively did not indicate the presence of reflux gastritis or esophagitis. CONCLUSIONS: Our procedure of LAPPG may be useful for early gastric cancer, especially intramucosal cancer.

Aged↗

Different modes of action of substance P in the motor control of the feline stomach and pylorus.

In an experimental in vivo model to study gastropyloric motility in the cat a contraction of the stomach and the pyloric sphincter was regularly obtained in animals subjected to electrical vagal nerve stimulation or local intraarterial (i.a.) injection of substance P (SP). Much more infrequently contractile motor responses were recorded at splanchnic nerve stimulation. The contractile effects of SP were sensitive to atropine or local infusion of a SP analogue, (D-Pro2,D-Trp7,9)-SP, indicating that SP activated a final common cholinergic neuron in both stomach and pylorus. However, there seemed to be separate transmission mechanisms in these two regions based on the results of the physiological studies. The vagally induced pyloric contraction was noncholinergic, nonadrenergic, but sensitive to ganglionic blockade (hexamethonium) or the SP analogue, indicating involvement of SP in a peptidergic pathway to the sphincter. The infrequent splanchnically induced pyloric contraction was sensitive to atropine, the SP analogue or ganglionic blockade (hexamethonium) in favour of SP acting on a final cholinergic neuron in this system. On the other hand the gastric contraction, obtained at either extrinsic nerve stimulations or local i.a. injection of SP, was sensitive to atropine or the SP analogue but hexamethonium resistant. These findings suggest antidromic activation of SP-containing axon collaterals of the extrinsic nerves terminating on cholinergic neurons of the gastric wall. When afferent C-fibres of the vagal nerve were selectively activated by local heating, pyloric contraction and gastric relaxation were obtained via vago-vagal reflexes. After cervical vagotomy heating of the distal end of the vagal nerve elicited a gastric contraction, previously demonstrated to be atropine sensitive and hexamethonium resistant, but no pyloric motor response. This suggests that the antidromic activation mechanism was present only in the stomach, not in the pylorus.

Animals↗

Pharmacological examination of cholecystokinin (CCK-8)-induced contractile activity in the rat isolated pylorus.

The actions of cholecystokinin (CCK) in the production of a satiety-like state have been suggested to be mediated via receptors for CCK which are located in the pylorus. We investigated the actions of CCK and other pharmacological agents upon the isolated rat pylorus in vitro. We used the change in isometric tension of the tissue preparation (contraction amplitude) as the measure of the effects of the pharmacological agents. Cholecystokinin COOH-terminal octapeptide (CCK-8) was observed to elicit contraction in a dose-dependent manner, with the half-maximal dose (ED50) in the vicinity of 1 nM. Rapid desensitization to CCK was observed. The contraction amplitude was atropine-independent, and was not significantly antagonized by a wide variety of other pharmacological agents. The Na+-channel blocker tetrodotoxin was without effect upon contractile amplitude, as was the K+-channel blocker 4-aminopyridine, except at very high concentrations. Neurotensin, bombesin, and the substance P and bombesin antagonist spantide all elicited contraction in the isolated tissue; neurotensin had a similar potency to CCK-8 and bombesin was 10-15-fold less potent than CCK-8. Unsulfated CCK-8 was at least 170-fold less potent than sulfated CCK-8 and tetragastrin was at least 500-fold less potent than CCK-8. These results suggest that pyloric CCK receptors, which appear to have a pharmacological profile typical of peripheral CCK receptors, may have a physiological role in the peptidergic control of gastric emptying in the rat.

Animals↗

Cancer of the pancreas. Pylorus-preserving resection of the pancreas.

Pylorus-preserving pancreaticoduodenectomy represents an important advance in the history of pancreatic surgery. The operation can be performed with a low operative mortality and morbidity, is technically easier than the standard Whipple resection, and it minimizes the long-term physiological disturbance to the patient. Clinical and experimental evidence has substantiated the view that preservation of the pylorus reduces the incidence of marginal anastomotic ulceration following pancreatectomy. Although gastric emptying may be prolonged transiently in the immediate postoperative period, this complication is easily managed, and is hardly a frequent long-term problem. PPPD is associated with a lower incidence of enterogastric reflux, dumping and diarrhoea than the classical Whipple operation, and patients who have had PPPD are more likely to regain their preoperative and preillness weight. Initial concerns about the use of PPPD in malignant disease have not been borne out, and should now be considered for curative or palliative resections of lesions in the periampullary region including the head of the pancreas. Present data suggest that PPPD does not compromise the long-term survival in patients with periampullary cancers. There is little doubt that the excellent results reported with this procedure as with other forms of major pancreatic surgery, are not simply related to improvements in surgical technique but to establishment of specialist pancreatic surgery.

Anastomosis, Surgical↗

Duodenal cancer arising from the remaining duodenum after pylorus-preserving pancreatoduodenectomy for ampullary cancer in familial adenomatous polyposis.

We herein report a rare occurrence of duodenal cancer arising from the remaining duodenum after pylorus-preserving pancreatoduodenectomy for ampullary cancer in familial adenomatous polyposis (FAP). In this patient, proctocolectomy and ileoanal anastomosis for FAP had been performed 11 years earlier. During the current admission, the patient was diagnosed with adenocarcinoma in the Vater's ampulla using imaging and pathological examinations. In addition, a pylorus-preserving pancreatoduodenectomy was performed. The tumor was a well-differentiated tubular adenocarcinoma and no other polyps were identified in the duodenum by pathological examination. However, 1 year after surgery, a polypoid lesion measuring 15 x 15 mm was indicated in the remaining duodenum by endoscopic surveillance. This lesion was completely resected by endoscopic mucosal resection and the resected specimen revealed well-differentiated tubular adenocarcinoma in an adenomatous lesion. This report suggests that resection of the total duodenum is essential for duodenal neoplasms in FAP to prevent a recurrence in the remaining duodenum.

Adenocarcinoma↗

Pylorus-preserving gastrectomy with radical lymph node dissection based on anatomical variations of the infrapyloric artery.

We devised a method for performing pylorus-preserving gastrectomy (PPG) with radical lymph node dissection without compromising pyloric blood flow, based on vascular anatomical evaluation of 210 celiac angiograms. The origin of the infrapyloric artery was variable, but consistently supplied blood flow to the pylorus and the posterior wall of the antrum. When the infrapyloric artery originated from the gastroduodenal artery or from one of its pancreatic branches (type A, 88%), the right gastroepiploic artery was divided at its origin, allowing the excision of all adjacent lymph nodes. When the infrapyloric artery originated from the right gastroepiploic artery (type B, 12%), the right gastroepiploic artery was divided distal to the infrapyloric artery origin and the short right gastroepiploic artery remnant was skeletonized of lymph nodes. We have used this technique to perform PPG on 25 patients with early gastric cancer in the middle third of the stomach with minimal morbidity and no mortality.

Adult↗

The multi-channelled pylorus.

The entity of multiple pyloric channels may be congenital but the majority are acquired lesions representing fistulae secondary to peptic ulcer disease in the pyloroduodenal region. The fistula usually joins the lesser curvature of the stomach with the superior aspect of the duodenal bulb. The multichannelled pylorus produces a characteristic radiological appearance on barium mean examination with a double or split barium column in the region of the pylorus. Four cases are described and illustrated.

Aged↗

The role of nitric oxide in the gastric acid secretion induced by ischemia-reperfusion in the pylorus-ligated rat.

In a rat model of the ischemia-reperfusion with pylorus ligation, gastric ulcer was formed, although gastric acid secretion was reduced. When the polymorphonuclear leukocytes were inactivated in advance, gastric ulcer was not formed, but acid secretion was increased, indicating that gastric acid is not a cause of the ulcer formation in this model. The mechanism of gastric acid suppression accompanied by ischemia-reperfusion was examined in relation to the role of oxygen-free radicals in this rat model. Prior administration of superoxide dismutase did not modulate acid secretion, but N-nitro-L-arginine methyl ester (L-NAME) increased acid secretion. The action of L-NAME was antagonized specifically by L-arginine, but not by D-arginine. S-nitroso-N-acetylpenicillamine did not inhibit basal acid secretion but antagonized the action of L-NAME. Aminoguanidine increased significantly the gastric acid output that was suppressed by ischemia-reperfusion. When polymorphonuclear leukocytes were inactivated by treatment with their antibody, the gastric acid output recovered to the level in the pylorus-ligated rat without ischemia-reperfusion. These results suggested that nitric oxide (NO) produced by the infiltrated polymorphonuclear leukocytes plays an important role in the suppression of acid secretion induced by ischemia-reperfusion.

Animals↗

Effect of 2-deoxy-D-glucose on acetylcholine and histamine levels in gastric juice of pylorus-ligated rats anesthetized with urethane.

Acetylcholine (ACh) in gastric juice was detected and measured by pretreatment of acetylcholinesterase inhibitor, 1 mM eserine (1 ml/rat, p.o.), in pylorus-ligated rats, by liquid chromatography with electrochemical detection. In order to elucidate whether or not the ACh level in gastric juice reflects the activity of cholinergic neurons, the effect of 2-deoxy-D-glucose (2-DG), a vagus stimulant, on the levels of ACh, histamine and gastric acid in gastric juice was investigated in pylorus-ligated rats anesthetized with urethane (1.25 g/kg, i.p.). Under the non-anesthetic condition, ACh, histamine and gastric acid levels were 100+/-25 pmol/h, 120+/-10 ng/h, and 240+/-32 microequiv./h, respectively. These levels were completely inhibited by urethane anesthesia. Under the anesthetized condition, 2-DG (50-200 mg/kg, i.v.) significantly increased ACh and histamine levels in gastric juice, as well as acid secretion. The 2-DG (200 mg/kg, i.v.)-induced increases in these levels were completely inhibited by vagotomy. These results suggest that ACh level measured in gastric juice reflects the activity of cholinergic transmission. Furthermore, these results also support the conclusion that vagus stimulation facilitates not only cholinergic transmission but also histaminergic transmission related to gastric acid secretion.

Acetylcholine↗

Ultrasonographic features of normalization of the pylorus after pyloromyotomy for hypertrophic pyloric stenosis.

PURPOSE: The purpose of this study was to describe the time course, early postoperative changes, and morphologic features of normalization of the pylorus after pyloromyotomy for hypertrophic pyloric stenosis. METHODS: The subjects were 17 infants (9 boys, 8 girls) who underwent umbilical incision Ramstedt pyloromyotomy. The pyloric muscle mass was measured immediately before the operation and then at intervals from 3 days to 6 months after the operation using a 7.5-MHz ultrasound probe. RESULTS: In longitudinal section, the dorsal part of the pyloric muscle thickened transiently and then thinned to normal values by 5 months after the operation. It was 5.1 +/- 0.8 mm (mean +/- SD) preoperatively, increased to 6.0 +/- 0.3 mm by day 3 after the operation (P <.05), and thinned to 2.8 +/- 0.2 mm by 5 months after the operation. Concomitantly, the length of the pylorus gradually decreased (from 20.1 +/- 2.9 mm preoperatively to 16.9 +/- 2.7 mm by 3 days postoperatively [P <.05] and to less than 15 mm, by 4 months). In transverse section, the muscle normalized as in the longitudinal section. At the site of the incision it was 4.3 +/- 0.4 mm thick preoperatively, thickened to 4.6 +/- 0.4 mm by 3 days after the operation (P <.05), thinned to 2.1 +/- 0.9 mm by 7 days (P <.05), and then increased slightly, but always was less than 3.0 mm. Morphologically, in transverse section, the incised area looked like a wedge by 3 days after the operation. CONCLUSIONS: After pyloromyotomy for hypertrophic pyloric stenosis, there is an early transient increase in muscle thickness within the first few postoperative days followed by a slow decrease that reaches normal thickness (<3 mm) by 5 months. This decrease in thickness is accompanied by a gradual decrease in length to 75% of the preoperative value by 5 months. The morphologic features in this normalization are first a wedge (day 3), then a flat tire (days 7 and 14), and finally an elongated ring (5 months). J Pediatr Surg 36:582-586.

Digestive System Surgical Procedures↗

Double pylorus and esophageal achalasia.

29 cases of double pylorus have been reported so far. It is thought that in 85% of the cases it has been due to a fistulous gastro-duodenal ulcer and the remaining 15% would be of a congenital origin. In the case we have reported the double pylorus is believed to be a congenital anomaly associated with a mega-esophagus of similar etiology.

Aged↗

Duplication of the pylorus: an elusive diagnosis.

A 20-day old female with symptoms of intermittent gastric outlet obstruction since the third day after birth was subjected to surgical exploration. Laparotomy revealed duplication of the pylorus communicating with a normal gastric cavity. The patient was successfully treated by excising the wall separating the duplication from the pylorus. Five cases of pyloric duplication reported so far in the English literature are reviewed.

Female↗

Is pyloric function preserved in pylorus-preserving pancreaticoduodenectomy?

OBJECTIVE: To assess the function of the pylorus after pylorus-preserving pancreaticoduodenectomy (PPPD) done for periampullary or pancreatic cancer. DESIGN: Prospective, observational controlled clinical study. SETTING: Teaching hospital, Italy. SUBJECTS: 17 patients who had undergone PPPD, and 15 healthy control subjects. INVESTIGATIONS: Endoscopy to check for gastritis and marginal ulcers and 24 h-pH monitoring and 99mTc HIDA scintigraphy to detect jejunogastric reflux. Scintigraphy was also used to evaluate gastric and jejunal transit after a solid meal labelled with 99mTc colloid sulphur. MAIN OUTCOME MEASURES: Signs of delayed gastric emptying, jejunogastric reflux and gastric outlet obstruction in the short and long term. RESULTS: In the early postoperative period only 1 patient had delayed gastric emptying. In the long term, two patients had symptoms of dyspepsia and 8/11 showed alkaline reflux with persistent gastric pH more than 4 for more than 12 hours; 3 had histological signs of gastritis. There was no difference in gastric emptying compared with controls, but three patients had prolonged emptying time (T1/2 more than 85 minutes). Endoscopy findings correlated with pH monitoring results. CONCLUSIONS: After PPPD, most patients have abnormal pyloric function, but it is clinically evident in only a small proportion.

Adult↗

Preservation of the pylorus in pancreaticoduodenectomy a follow-up evaluation.

We have previously reported our efforts to minimize postgastrectomy symptoms in two patients with benign disease who underwent resection of the head of the pancreas and the duodenum. In these cases the pylorus and first portion of the duodenum were preserved during pancreaticoduodenectomy. Our experience has now been extended to encompass 18 patients, eight of whom were available for comprehensive evaluation an average of six months postoperation. These studies have attempted to differentiate malabsorption of pancreatic insufficiency from possible gastrointestinal dysfunction of the new alimentary connection. Pancreatic insufficiency was evaluated by a 72-hour stool collection and radioactive trioctanoate (RATO) test. Gastrointestinal absorption was evaluated by D-xylose excretion and the Schilling test, as well as serum vitamin. A, vitamin B-12, carotene, folate, iron, and total iron binding capacity. Gastrointestinal secretion and motility were assessed by using pyloric fluoroscopy, gastric barium emptying, the Hunt test, and gastric acid analysis. Finally, a questionnaire regarding clinical symptoms of postgastrectomy syndromes and malabsorption was answered. Although every patient exhibited marked pancreatic insufficiency by laboratory tests, 88% described normal formed bowel movements, and weight loss was claimed by only 25%. Other test findings were generally normal. While the follow-up period has been limited to three years, the current data demonstrate that gastrointestinal function subsequent to preservation of the pylorus has not thus far predisposed to postgastrectomy syndromes or marginal ulcers. All of the patients required intensive pancreatic enzyme replacement.

Adolescent↗

Pylorus-preserving pancreatoduodenectomy. A clinical and physiologic appraisal.

Since 1978, 252 patients from different centers in the world have undergone pylorus-preserving pancreatoduodenectomy. Fifty-five per cent of the patients had malignant tumors in the region of the head of the pancreas. The overall operative mortality rate was 2.8%. Anastomotic leakage and fistulae occurred in 19% of the patients. Pancreatic, biliary, and enteric fistulae represented 11%, 4%, and 4%, respectively. Peptic ulcers were subsequently diagnosed in seven patients (3%), two of whom required vagotomy and antrectomy. Delayed recovery of gastric function was the most common complication of this operation, with an overall incidence of 30%. Although the cause of this gastric dysfunction is unknown, its transient nature in most patients makes expectant therapy with gastric tube drainage the best remedy when the problem is encountered. Pylorus-preserving pancreatoduodenectomy decreased the incidence of postgastric surgery syndromes that are commonly associated with the standard Whipple operation. The existing data support the continued use of the operation and the need for future laboratory and clinical investigation of its physiologic impact.

Adenocarcinoma↗

Pylorus preservation has no impact on delayed gastric emptying after pancreatic head resection.

OBJECTIVES: Delayed gastric emptying (DGE) has been specifically attributed to pylorus-preserving pancreaticoduodenectomy (PPPD). As PPPD has been shown to be comparable with the classic Kausch-Whipple pancreaticoduodenectomy (KWPD) in terms of oncological radicality, DGE has advanced to be the leading argument for hemigastrectomy in PD. METHODS: A prospective, nonrandomized comparison of patients undergoing PPPD (n = 113), KWPD (n = 19), and duodenum-preserving, pancreatic head resection (DPPHR, n = 18) for various diseases was performed. First, groups were analyzed with regard to structural similarity; then, they were compared with special emphasis on DGE and other postoperative complications. Finally, further prognostic factors were sought that had an impact on DGE. RESULTS: The PPPD group was comparable with the KWPD group, but not to the DPPHR population. The in-clinic course after DPPHR compared favorably with PPPD as well as KWPD, and, here, no DGE occurred. The overall morbidity rates of PPPD and KWPD were comparable; 1 patient died in hospital (mortality rate, 0.7%). The gastric tube after PPPD and KWPD could be withdrawn at a median of 2 and 3 days, respectively, a liquid diet was started after 4 and 5 days, respectively, and a full diet was tolerated after 10 days each (n.s.). DGE was distributed evenly among PPPD (12%) and KWPD patients (21%, n.s.), and it was noted almost exclusively when other postoperative complications were present (P < 0.0001). No further prognostic factors influencing DGE could be identified. CONCLUSION: Pylorus preservation does not increase the frequency of DGE. DGE almost exclusively occurs as a consequence of other postoperative complications. Therefore, DGE should not be used as an argument to advocate hemigastrectomy in PPPD.

Follow-Up Studies↗