Assessment of Vagus Nerve Injury Through Sham Feeding

Assessment of Vagus Nerve Injury Through Sham Feeding | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Assessment of Vagus Nerve Injury Through Sham Feeding Tian Li, Billings Sabrina, Rex-Kam Siu, Brian Lacy, Timothy A. Woodward This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7350147/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Background: Vagal nerve injury can cause non-specific symptoms and is challenging to assess. Pancreatic polypeptide (PP) release after sham feeding is a surrogate marker of vagal function. This study evaluated vagal integrity using sham feeding-induced PP measurement, and examined associations between symptoms, PP levels, and gastric emptying. Method: This was a retrospective study of patients who underwent sham feeding from 2018 to present. We collected demographic and clinical data, sham feeding results, indication for study, gastric emptying data. A 50% increase in PP level within 30 mins compared to baseline was considered normal. A gastric emptying scan was classified as delayed if < 75% of the material emptied at 4 hours. Results: 53 patients were included (58.5% women) with a mean age of 57.2 years. The main GI symptoms were nausea and vomiting (21, 40.0%) and diarrhea (14, 26.4%). 36 of 53 patients had a history of abdominal surgery, with Nissen fundoplication including open and laparoscopic being the most common surgeries (10, 27.8%). The fold of PP changes between abnormal and normal groups are significantly different (p = 0). In 23 patients with symptoms of nausea and vomiting, symptoms of nausea and vomiting were found to have a robust correlation with a positive sham feeding result (21, 91.3%), compared with gastric emptying scintigraphy (14, 60.9%). Conclusion: Sham feeding is consistently abnormal in patients with predominant symptoms of nausea and vomiting while the correlation between gastric scintigraphy result and gastroparesis symptoms was not significant. Sham feeding may be a valuable test when assessing patients with symptoms of nausea and vomiting. sham feeding vagal nerve function foregut surgery gastroparesis Introduction The vagus nerve, through its efferent and afferent pathways, modulates various aspects of gastrointestinal physiology, including motility and hormone secretion. Vagal nerve injury can occur for a variety of reasons, one of the most common being inadvertent injury during anti-reflux surgery. Vagal nerve injury may lead to non-specific symptoms such as early satiety, nausea, vomiting, bloating, and epigastric discomfort. Pancreatic polypeptide (PP) is a 36 amino acid polypeptide hormone first discovered as a contaminant in insulin preparations[ 1 ]. PP is secreted by pancreatic F cells and primarily regulated by vagal stimulation by activating cholinergic pathways during the cephalic phase of digestion. For instance, electrical stimulation of the vagal nerve increases PP secretion, and this effect can be inhibited by atropine[ 2 ]. Meanwhile, hormones such as gastrin, cholecystokinin (CCK) and secretin also stimulate PP secretion, while somatostatin acts as an inhibitor. Evaluation of vagal nerve injury is difficult without a validated objective test to assess vagus nerve function. Pancreatic polypeptide response to vagal stimulation using sham feeding or insulin-induced hypoglycemia has been used to check completeness of vagotomy. Although it did not achieve widespread acceptance and has largely fallen out of favor among most gastrointestinal surgeons due to the infrequent performance of elective vagotomy, assessing changes in pancreatic polypeptide (PP) levels following a sham meal may serve as a viable surrogate marker[ 3 ]. Meanwhile, the relationship between sham feeding and gastroparesis is not well documented in the literature. Thus, our aim was to assess vagal nerve integrity through sham feeding as well as to compare gastric emptying rates to reported symptoms to further illustrate the relationship between autonomic nerve dysfunction and delayed gastric emptying. Methods Study Population Adult patients aged 18 and older who underwent a sham feeding study at Mayo Clinic Florida from 2018 to 2024 were included. The study was approved by our institution Institutional Review Board (IRB NO. 23-009850). Data was abstracted from the electronic medical record including patient demographics and symptoms. We collected demographic and cardinal gastrointestinal (GI) symptoms, prior surgery or procedure history, date of the surgery or procedure, sham feeding results, the primary indication for sham feeding study, gastric emptying data, high-resolution esophageal manometry (HRM) result, numbers of GI providers seen and investigation tests done for this condition. Assessment of Pancreatic Polypeptide Response to Modified Sham Feeding Before their scheduled test, patients presented for the meal-stimulated PP test after an overnight fast. Participants fasted for 8 hours, abstained from tobacco and coffee for 12 hours, and stopped all antihistamines, antispasmodics, cholinergic and antidepressants for 48 hours. A small intravenous catheter was inserted into a vein in the patient’s arm. Two baseline blood samples (5 ml) were obtained. The study assistant then prepared a bacon and cheese sandwich in the room with the patient. The meal was given to the patient, and they were asked to chew the meal but not to swallow it. Each bite was chewed and then discarded into a container. Samples for PP determination were then obtained every 5 minutes for a total of 30 minutes. Hence there were a total of eight samples obtained during each test (two baseline and six after sham feeding). The samples were processed, and PP levels (pg/ml) were assayed with rabbit anti-human PP and radiolabeled PP as previously described. The average of the two baseline samples was used as the baseline PP level. The highest level obtained with any one of the subsequent six determinations after the sham-meal was considered the maximum. In our laboratory, A 50% increase in PP level within 30 mins compared to baseline after sham meal was considered normal. If the peak increment is < 50%, then the sham feeding test was considered abnormal. Gastric Emptying Evaluation The gold standard for evaluating gastric emptying is gastric emptying scintigraphy, which measures the rate at which a radiolabeled solid meal leaves the stomach over a period of 3 to 4 hours. We have classified a delayed gastric emptying as if less than 75% of the material was emptied at 4 hours. Rapid gastric emptying at 2 hours is defined as less than 30% retention of a solid meal at the 2- hour mark during a gastric emptying scintigraphy test. (Normal range of gastric emptying at one, two and four hours are 8–37%, 36–79% and 87–100%, respectively according to MCF criteria) Results Baseline Demographics and Clinical Characteristics 53 patients were included (58.5%, n = 31 women) with a mean age of 57.2 years. Most patients were white (n = 40), and the mean BMI was 27.6 kg/m 2 . The main GI symptoms were nausea and vomiting (21, 40.0%) and diarrhea (14, 26.4%). The average weight loss from symptoms onset was 22.7 lb. (range: 0-100lb). 36 of 53 (67.9%) patients had a history of abdominal surgery, with Nissen fundoplication including open and laparoscopic being the most common surgery (10, 27.8%) followed by hiatal hernia repair (HHR) with Nissen fundoplication (6, 16.7%) and HHR (4, 11.1%). (Table 1.) Vagus Nerve Function The mean baseline PP level of abnormal compared to normal tests was 189.3 pg/mL and 106.2 pg/mL, respectively (p = 0.30). The mean peak PP level of abnormal compared to normal was not significantly different, 220.9 pg/mL and 234.2pg/mL, respectively (p = 0.9). However, the fold of PP changes between abnormal and normal groups were significantly different (p = 0). Gastric Emptying Scintigraphy Results Among the 45 patients who underwent gastric emptying test, 21 (46.67%) patients have abnormal gastric emptying result including 3 rapid gastric emptying at 2 hours. Two patients who had rapid gastric emptying results had HHR, and the other one had exploratory complicated by bowel perforation. HRM Results 25 patients had undergone HRM, with 8 esophagogastric junction outflow obstruction (EGJOO), 9 normal, 3 distal esophageal spasm (DES), 3 ineffective esophageal motility (IEM), one type II achalasia and one type III achalasia. Relation between Gastric Emptying, Vagus Nerve Function and Gastrointestinal Symptoms In 23 patients with symptoms of nausea and vomiting, symptoms of nausea and vomiting were found to have a robust correlation with a positive sham feeding result (21, 91.3%), compared with gastric emptying scintigraphy (14, 60.9%) (Table 2 ). Table 2 Summary of the Relation Between Gastric Emptying, Vagus Nerve Function and Gastrointestinal Symptoms Primary indication for sham feeding GI symptoms Gastric empty Sham feeding Manometry result PP peak/ baseline ratio GER dyspepsia normal normal not performed 0.99 abdominal pain diarrhea abnormal normal not performed 0.79 abdominal pain nausea/vomiting normal abnormal normal 0.83 gastroparesis nausea/vomiting abnormal abnormal not performed 0.93 gastroparesis nausea/vomiting abnormal abnormal not performed 0.91 chronic nausea and vomiting diarrhea, dysphagia abnormal abnormal type II achalasia 0.99 GER pyrosis/ heartburn normal not performed 0.96 diarrhea diarrhea normal normal EGJ outflow obstruction 1.02 gastroparesis no appetite normal abnormal not performed 1.02 GER diarrhea, dumping syndrome normal abnormal distal esophageal spasm 0.97 IBS diarrhea normal normal 1.11 chronic nausea and vomiting nausea/vomiting normal abnormal EGJ outflow obstruction due to fundoplication, distal esophageal spasm 1.02 gastroparesis nausea/vomiting, dyspepsia normal abnormal distal esophageal spasm 1.00 gastroparesis nausea/vomiting, diarrhea abnormal abnormal normal 1.00 GER dysphagia, dumping syndrome, diarrhea normal abnormal EGJ outflow obstruction 1.00 abdominal pain diarrhea, gas/bloating abnormal abnormal EGJ outflow obstruction 1.01 chronic nausea and vomiting nausea/vomiting abnormal abnormal EGJ outflow obstruction 1.10 chronic nausea and vomiting nausea/vomiting abnormal abnormal not performed 1.02 GER diarrhea, dyspepsia normal abnormal not performed 1.03 IBS dysphagia, diarrhea normal normal not performed 1.06 abdominal pain dysphagia abnormal normal type III achalasia 1.11 IBS diarrhea normal normal normal 1.11 abdominal pain nausea/vomiting abnormal abnormal not performed 1.11 abdominal pain decreased appetite normal abnormal EGJ outflow obstruction 1.14 constipation dyspepsia abnormal abnormal normal test 1.22 chronic nausea and vomiting nausea/vomiting abnormal normal not performed 1.22 chronic nausea and vomiting nausea/vomiting normal abnormal ineffective esophageal motility 1.22 GER nausea/vomiting, pyrosis/ heartburn normal abnormal ineffective esophageal motility 1.23 abdominal pain nausea/vomiting, dyspepsia abnormal abnormal not performed 1.24 chronic nausea and vomiting nausea/vomiting normal abnormal EGJOO 1.25 chronic nausea and vomiting nausea/vomiting abnormal abnormal EGJOO 1.32 dyspepsia, early satiety dyspepsia normal abnormal NA 1.32 chronic nausea and vomiting nausea/vomiting, diarrhea, abdominal pain, dyspepsia abnormal normal not ordered 1.44 chronic nausea and vomiting nausea/vomiting, dysphagia abnormal normal ordered but not done 1.45 diarrhea weight loss abnormal abnormal distal esophageal spasm 1.50 chronic nausea and vomiting nausea/vomiting abnormal abnormal not ordered 1.51 chronic nausea and vomiting nausea/vomiting, gas/bloating, dysphagia normal abnormal IEM 1.52 chronic nausea and vomiting nausea/vomiting, dyspepsia, dumping syndrome abnormal abnormal 1.52 chronic nausea and vomiting dumping syndrome, gas/bloating, nausea/vomiting abnormal normal normal 1.55 amyloid dysphagia, gas/bloating, constipation normal abnormal not ordered 1.56 chronic nausea and vomiting dumping syndrome, gas/bloating, nausea/vomiting normal abnormal not tested 1.60 diarrhea diarrhea, dumping syndrome normal not ordered 1.61 constipation constipation, gas/bloating abnormal 1.62 abdominal pain diarrhea, chronic abdominal pain abnormal 1.68 dysphagia dysphagia, dumping syndrome normal abnormal normal LES 1.73 abdominal pain gas/bloating, dysphagia normal abnormal normal 1.76 abdominal pain diarrhea, abdominal pain normal not ordered 1.79 amyloid dyspepsia, rectal bleeding, pancreatic insufficiency normal not ordered 2.32 bloating gas/bloating normal normal not ordered 2.32 abdominal pain abdominal pain, constipation normal normal not ordered 2.40 dumping syndrome abdominal pain, gas/bloating, dyspepsia, diarrhea abnormal normal normal 3.09 GER abdominal pain, nausea/vomiting abnormal not ordered 3.77 amyloid diarrhea normal not ordered 5.43 Abbreviations: Ineffective Esophageal Motility: IEM Esophagogastric Junction Outflow Obstruction: EGJOO Distal Esophageal Spasm: DES In those patients with symptoms of nausea and vomiting but with normal gastric emptying study, the sham feeding tests were all abnormal. There was no correlation between sham feeding result with symptoms of abdominal pain and GER. Medical and financial expenditure The care after apparent vagus nerve injury required significant medical resources, including an average of 4.43 visits and 8.47 tests per patient to evaluate key GI symptoms. Subgroup analysis Among 53 included for this study, there are 9 (44.4%, n = 4, female) patients included who were referred due to suspicion of amyloid involvement in GI tract. The average age of patients with amyloidosis is 67.12 years compared to 55.2 years in patients who had previous surgical procedures. Majority are white (88.9%, n = 8) and the mean BMI was 23.9 kg/m 2 . The mean GI symptoms are dyspepsia (33.3%, n = 3) and diarrhea (33.3%, n = 3). The average weight loss from symptoms onset was 12.9 lb. (range: 0-50lb) compared to 25.3 lb. (range: 0-100lb) for patients with prior abdominal surgical history. 6 amyloidosis patients have positive sham feeding results. Only 4 patients have underwent gastric emptying scintigraphy and half of them are abnormal. The number of tests ordered for patients with amyloidosis is less than patients who developed vagus nerve injury after surgical procedures, 4 compared to 9.34, respectively (Table 3 ). Table 3 Comparison Of Patients Diagnosed with Amyloidosis with Patient Who Had Previous Abdominal Surgical History Patients with amyloidosis (n = 9) Patient with previous surgical history (n = 44) Age 67.1 55.2 Female 44.4% 59.1% Race 9 white 34 White 2 Black one Asian one Hispanic 5 did not disclose BMI 23.9 28.4 Mean weight loss (lb.) 12.86 25.3 GI symptoms dyspepsia 3 (33.3%) 7 (16%) diarrhea 3 (33.3%) 11(25%) nausea and vomiting 1 (11.1%) 20(45.55) dysphagia 1 (11.1%) 8(18.2%) gas/bloating 1 (11.1%) 9(20.5%) dumping syndrome 6(13.6%) abdominal pain 5(11.4%) heartburn 2(4.5%) others 4 (44.4%) Abnormal Gastric emptying scintigraphy 2 (50%, n = 4) 19 (47.5%, n = 40) Positive sham feeding 66.7% (n = 6) 63.7% (n = 28) Average number of tests ordered after presumed insult 4 9.3 Discussion We studied the characteristics of patients who underwent sham feeding study and the relationship between sham feeding results with GI symptoms, indication for sham feeding and medical resource usage. We have found out that in patient who had symptoms of nausea and vomiting, sham feeding is extremely sensitive to assess vagus nerve injury compared to gastric emptying scintigraphy, especially in patients who had prior abdominal surgery such as fundoplication and/or hiatal hernia repair. Sham feeding is a helpful tool to assist early diagnosis and potentially decreases the medical and financial expenditure associated with diagnosis process. Meanwhile, in patients with amyloidosis, sham feeding evaluation provides valuable information about vagus nerve involvement. Previous studies have shown that after anti-reflux surgery, 10–20% of patients had signs of vagus nerve dysfunction[ 4 , 5 ]. Abnormal vagus function cannot be measured or evaluated directly. In the past, an indirect method has been developed to measure vagus dysfunction by measuring the response of plasma pancreatic polypeptide secretion to insulin-induced hypoglycemia, the insulin hypoglycemia-PP test[ 2 , 6 ]. Vagal nerve dysfunction was speculated to cause functional dyspepsia through antral dysmotility, impaired gastric accommodation and visceral hypersensitivity[ 7 , 8 ]. This hypothesis was further validated by the result that vagal stimulation by sham feeding improves and even normalizes antral motility in functional dyspepsia patients[ 8 ]. Due to unspecific symptoms caused by vagal nerve injury, patients often underwent multiple testing to establish the diagnosis as shown in our study that the average number of tests are 9.3 in patients who have prior surgical history. Patients who presented with symptoms of nausea and vomiting have a very robust rate of abnormal sham feeding result compared to results of gastric emptying scintigraphy, thus is highly indictive of vagal nerve injury. Previous study showed some patients referred for anti-reflux surgery have evidence of abnormal vagus function that persists after surgery. Many patients with normal testing before surgery develop an abnormal test after surgery[ 9 ]. Though there is no study observing significant differences between surgical procedures with respect to the prevalence of vagus nerve injury[ 5 ], the percentage of patients with vagus nerve injury after intro(BM IV) was higher than after Nissen and Toupet fundoplication group[ 5 ]. Factors that potentially may increase the risk of vagus nerve injury during anti-reflux surgery include the presence of a large para-esophageal or axial hiatal hernia, previous abdominal surgery, severe esophagitis causing adhesions, poor visibility of the anatomy in the gastroesophageal region, anatomical variations of the vagus nerve, and limited experience with the procedure of the surgeon [ 4 ]. In patients diagnosed with amyloidosis with gastrointestinal symptoms, sham feeding would be helpful in detection of vagal nerve injury. In one study investigating the correlation of biopsy in amyloid patients and symptoms, 91.7% of patients demonstrated GI histopathologic positivity (paper forthcoming). The most common GI symptoms in patients with amyloidosis are abdominal pain, constipation, or diarrhea. Our study could help risk stratification and tailor treatment plan if there is suspicion of vagal nerve involvement. Octreotide was speculated to treat gastrointestinal sequelae from vagal nerve injury and has been used off-label to manage some symptoms in patient has severe dumping syndrome and refractory post-vagotomy diarrhea by inhibiting hormone secretion and slowing transit[ 10 ]. Conclusion Our research highlights the clinical implication of sham feeding in early diagnosis and management of GI symptoms especially in patients with prior foregut surgery or diagnosis of amyloidosis. Utilization of sham feeding could decrease significant medical and financial burden evaluating patients with symptoms after foregut surgery. Larger prospective studies are needed to better quantify the relationship between PP levels and gastric emptying in patients with prior foregut surgery who remain symptomatic. Declarations Consent to participation declaration: not applicable. Funding: not applicable. Clinical trial number: not applicable. Conflict of interest statement: None References Lin, T.M. and R.E. Chance, Candidate hormones of the gut. VI. Bovine pancreatic polypeptide (BPP) and avian pancreatic polypeptide (APP). Gastroenterology, 1974. 67 (4): p. 737-8. Schwartz, T.W., et al., Vagal, cholinergic regulation of pancreatic polypeptide secretion. J Clin Invest, 1978. 61 (3): p. 781-9. Balaji, N.S., et al., A safe and noninvasive test for vagal integrity revisited. Arch Surg, 2002. 137 (8): p. 954-8; discussion 958-9. Lindeboom, M.Y., et al., Gastric emptying and vagus nerve function after laparoscopic partial fundoplication. Ann Surg, 2004. 240 (5): p. 785-90. van Rijn, S., et al., Effect of Vagus Nerve Integrity on Short and Long-Term Efficacy of Antireflux Surgery. Am J Gastroenterol, 2016. 111 (4): p. 508-15. Schwartz, T.W., Pancreatic polypeptide: a hormone under vagal control. Gastroenterology, 1983. 85 (6): p. 1411-25. Gilja, O.H., et al., Impaired accommodation of proximal stomach to a meal in functional dyspepsia. Dig Dis Sci, 1996. 41 (4): p. 689-96. Lunding, J.A., et al., Vagal activation by sham feeding improves gastric motility in functional dyspepsia. Neurogastroenterol Motil, 2008. 20 (6): p. 618-24. DeVault, K.R., et al., Evaluation of vagus nerve function before and after antireflux surgery. Journal of Gastrointestinal Surgery, 2004. 8 (7): p. 881-887. Mackie, C.R., S.A. Jenkins, and M.N. Hartley, Treatment of severe postvagotomy/postgastrectomy symptoms with the somatostatin analogue octreotide. Br J Surg, 1991. 78 (11): p. 1338-43. Table 1 Table 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Tabel1.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 13 Oct, 2025 Reviews received at journal 10 Sep, 2025 Reviewers agreed at journal 20 Aug, 2025 Reviewers agreed at journal 18 Aug, 2025 Reviewers agreed at journal 18 Aug, 2025 Reviewers invited by journal 18 Aug, 2025 Editor assigned by journal 18 Aug, 2025 Submission checks completed at journal 13 Aug, 2025 First submitted to journal 11 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7350147","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":504402129,"identity":"949269e9-c580-422a-93dd-6ca4845fb3da","order_by":0,"name":"Tian Li","email":"","orcid":"","institution":"Mayo Clinic","correspondingAuthor":false,"prefix":"","firstName":"Tian","middleName":"","lastName":"Li","suffix":""},{"id":504402130,"identity":"b7f6ca10-b2d3-484e-a50f-f5b7498d8ef1","order_by":1,"name":"Billings Sabrina","email":"","orcid":"","institution":"Mayo Clinic","correspondingAuthor":false,"prefix":"","firstName":"Billings","middleName":"","lastName":"Sabrina","suffix":""},{"id":504402131,"identity":"317f5ef3-5e4a-4e78-b6af-e46743f23cb2","order_by":2,"name":"Rex-Kam Siu","email":"","orcid":"","institution":"Mayo Clinic","correspondingAuthor":false,"prefix":"","firstName":"Rex-Kam","middleName":"","lastName":"Siu","suffix":""},{"id":504402132,"identity":"4ca7c5a4-8228-4ca0-8929-e2300238cad8","order_by":3,"name":"Brian Lacy","email":"","orcid":"","institution":"Mayo Clinic","correspondingAuthor":false,"prefix":"","firstName":"Brian","middleName":"","lastName":"Lacy","suffix":""},{"id":504402134,"identity":"4a70ee6a-4ec5-4540-b173-9d2156a2699f","order_by":4,"name":"Timothy A. Woodward","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBUlEQVRIiWNgGAWjYBACgwMMDBJAmrFB/mEDkD7AwA+VYWwgqIUZpCbhAINkA/FaQFygFpAIfi3Hmw/e5qm5J9vAzNy64eOPO4mbrx1+JvGBwUZ2wwHsWszOHEu25jlWbAx0WNvNGQnPErfdTjOTnMGQZoxTy40cM+kctoREkJbbPAmHgVoSzKR5GA4n4tfyD0nL5tnp34Ba/uPUYg/SktuGpGWDdA7IlgM4tViC/PK3L8G4DeyXtMPGM27nFFvOMEg2nolDCyjEbs74liDbz8z+7MYHm8Oy/bPTN974UGEn24dDCxywQWnHBgYGFgkGAwLKUTwHxMwfSNAwCkbBKBgFwx8AAB6fbD4n7W71AAAAAElFTkSuQmCC","orcid":"","institution":"Mayo Clinic","correspondingAuthor":true,"prefix":"","firstName":"Timothy","middleName":"A.","lastName":"Woodward","suffix":""}],"badges":[],"createdAt":"2025-08-12 01:08:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7350147/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7350147/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":89930624,"identity":"95b69ec8-997a-4891-8c4c-e1ba178b1e6b","added_by":"auto","created_at":"2025-08-26 14:09:32","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":948042,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7350147/v1/bbbc177e-4eeb-4806-9914-1d19a14d04c0.pdf"},{"id":89929503,"identity":"c1e6015c-b442-40c9-bfc6-008c259cbfe1","added_by":"auto","created_at":"2025-08-26 14:01:32","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":20221,"visible":true,"origin":"","legend":"","description":"","filename":"Tabel1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7350147/v1/d287a9e55f3a41b53574db74.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Assessment of Vagus Nerve Injury Through Sham Feeding","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe vagus nerve, through its efferent and afferent pathways, modulates various aspects of gastrointestinal physiology, including motility and hormone secretion. Vagal nerve injury can occur for a variety of reasons, one of the most common being inadvertent injury during anti-reflux surgery. Vagal nerve injury may lead to non-specific symptoms such as early satiety, nausea, vomiting, bloating, and epigastric discomfort. Pancreatic polypeptide (PP) is a 36 amino acid polypeptide hormone first discovered as a contaminant in insulin preparations[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. PP is secreted by pancreatic F cells and primarily regulated by vagal stimulation by activating cholinergic pathways during the cephalic phase of digestion. For instance, electrical stimulation of the vagal nerve increases PP secretion, and this effect can be inhibited by atropine[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Meanwhile, hormones such as gastrin, cholecystokinin (CCK) and secretin also stimulate PP secretion, while somatostatin acts as an inhibitor. Evaluation of vagal nerve injury is difficult without a validated objective test to assess vagus nerve function. Pancreatic polypeptide response to vagal stimulation using sham feeding or insulin-induced hypoglycemia has been used to check completeness of vagotomy. Although it did not achieve widespread acceptance and has largely fallen out of favor among most gastrointestinal surgeons due to the infrequent performance of elective vagotomy, assessing changes in pancreatic polypeptide (PP) levels following a sham meal may serve as a viable surrogate marker[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Meanwhile, the relationship between sham feeding and gastroparesis is not well documented in the literature. Thus, our aim was to assess vagal nerve integrity through sham feeding as well as to compare gastric emptying rates to reported symptoms to further illustrate the relationship between autonomic nerve dysfunction and delayed gastric emptying.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy Population\u003c/h2\u003e\u003cp\u003eAdult patients aged 18 and older who underwent a sham feeding study at Mayo Clinic Florida from 2018 to 2024 were included. The study was approved by our institution Institutional Review Board (IRB NO. 23-009850). Data was abstracted from the electronic medical record including patient demographics and symptoms. We collected demographic and cardinal gastrointestinal (GI) symptoms, prior surgery or procedure history, date of the surgery or procedure, sham feeding results, the primary indication for sham feeding study, gastric emptying data, high-resolution esophageal manometry (HRM) result, numbers of GI providers seen and investigation tests done for this condition.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eAssessment of Pancreatic Polypeptide Response to Modified Sham Feeding\u003c/h3\u003e\n\u003cp\u003eBefore their scheduled test, patients presented for the meal-stimulated PP test after an overnight fast. Participants fasted for 8 hours, abstained from tobacco and coffee for 12 hours, and stopped all antihistamines, antispasmodics, cholinergic and antidepressants for 48 hours. A small intravenous catheter was inserted into a vein in the patient\u0026rsquo;s arm. Two baseline blood samples (5 ml) were obtained. The study assistant then prepared a bacon and cheese sandwich in the room with the patient. The meal was given to the patient, and they were asked to chew the meal but not to swallow it. Each bite was chewed and then discarded into a container. Samples for PP determination were then obtained every 5 minutes for a total of 30 minutes. Hence there were a total of eight samples obtained during each test (two baseline and six after sham feeding). The samples were processed, and PP levels (pg/ml) were assayed with rabbit anti-human PP and radiolabeled PP as previously described.\u003c/p\u003e\u003cp\u003eThe average of the two baseline samples was used as the baseline PP level. The highest level obtained with any one of the subsequent six determinations after the sham-meal was considered the maximum. In our laboratory, A 50% increase in PP level within 30 mins compared to baseline after sham meal was considered normal. If the peak increment is \u0026lt;\u0026thinsp;50%, then the sham feeding test was considered abnormal.\u003c/p\u003e\n\u003ch3\u003eGastric Emptying Evaluation\u003c/h3\u003e\n\u003cp\u003eThe gold standard for evaluating gastric emptying is gastric emptying scintigraphy, which measures the rate at which a radiolabeled solid meal leaves the stomach over a period of 3 to 4 hours.\u003c/p\u003e\u003cp\u003eWe have classified a delayed gastric emptying as if less than 75% of the material was emptied at 4 hours. Rapid gastric emptying at 2 hours is defined as less than 30% retention of a solid meal at the 2- hour mark during a gastric emptying scintigraphy test.\u003c/p\u003e\u003cp\u003e(Normal range of gastric emptying at one, two and four hours are 8\u0026ndash;37%, 36\u0026ndash;79% and 87\u0026ndash;100%, respectively according to MCF criteria)\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003eBaseline Demographics and Clinical Characteristics\u003c/h2\u003e\u003cp\u003e53 patients were included (58.5%, n\u0026thinsp;=\u0026thinsp;31 women) with a mean age of 57.2 years. Most patients were white (n\u0026thinsp;=\u0026thinsp;40), and the mean BMI was 27.6 kg/m\u003csup\u003e2\u003c/sup\u003e. The main GI symptoms were nausea and vomiting (21, 40.0%) and diarrhea (14, 26.4%). The average weight loss from symptoms onset was 22.7 lb. (range: 0-100lb). 36 of 53 (67.9%) patients had a history of abdominal surgery, with Nissen fundoplication including open and laparoscopic being the most common surgery (10, 27.8%) followed by hiatal hernia repair (HHR) with Nissen fundoplication (6, 16.7%) and HHR (4, 11.1%). (Table\u0026nbsp;1.)\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eVagus Nerve Function\u003c/h2\u003e\u003cp\u003eThe mean baseline PP level of abnormal compared to normal tests was 189.3 pg/mL and 106.2 pg/mL, respectively (p\u0026thinsp;=\u0026thinsp;0.30). The mean peak PP level of abnormal compared to normal was not significantly different, 220.9 pg/mL and 234.2pg/mL, respectively (p\u0026thinsp;=\u0026thinsp;0.9). However, the fold of PP changes between abnormal and normal groups were significantly different (p\u0026thinsp;=\u0026thinsp;0).\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eGastric Emptying Scintigraphy Results\u003c/h3\u003e\n\u003cp\u003eAmong the 45 patients who underwent gastric emptying test, 21 (46.67%) patients have abnormal gastric emptying result including 3 rapid gastric emptying at 2 hours. Two patients who had rapid gastric emptying results had HHR, and the other one had exploratory complicated by bowel perforation.\u003c/p\u003e\n\u003ch3\u003eHRM Results\u003c/h3\u003e\n\u003cp\u003e25 patients had undergone HRM, with 8 esophagogastric junction outflow obstruction (EGJOO), 9 normal, 3 distal esophageal spasm (DES), 3 ineffective esophageal motility (IEM), one type II achalasia and one type III achalasia.\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eRelation between Gastric Emptying, Vagus Nerve Function and Gastrointestinal Symptoms\u003c/h2\u003e\u003cp\u003eIn 23 patients with symptoms of nausea and vomiting, symptoms of nausea and vomiting were found to have a robust correlation with a positive sham feeding result (21, 91.3%), compared with gastric emptying scintigraphy (14, 60.9%) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSummary of the Relation Between Gastric Emptying, Vagus Nerve Function and Gastrointestinal Symptoms\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePrimary indication\u003c/p\u003e\u003cp\u003e for sham feeding\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGI symptoms\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGastric empty\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSham feeding\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eManometry result\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ePP peak/ baseline ratio\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.99\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.79\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.83\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003egastroparesis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.93\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003egastroparesis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.91\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, dysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003etype II achalasia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.99\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003epyrosis/ heartburn\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.96\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJ outflow obstruction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003egastroparesis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eno appetite\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, dumping syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003edistal esophageal spasm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.97\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIBS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJ outflow obstruction due to fundoplication, distal esophageal spasm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003egastroparesis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, dyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003edistal esophageal spasm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.00\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003egastroparesis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, diarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.00\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edysphagia, dumping syndrome, diarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJ outflow obstruction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.00\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, gas/bloating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJ outflow obstruction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJ outflow obstruction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.02\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, dyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.03\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIBS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edysphagia, diarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.06\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003etype III achalasia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIBS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edecreased appetite\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJ outflow obstruction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.14\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003econstipation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal test\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.22\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.22\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eineffective esophageal motility\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.22\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, pyrosis/ heartburn\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eineffective esophageal motility\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.23\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, dyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot performed\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.24\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJOO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.25\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEGJOO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003edyspepsia, early satiety\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, diarrhea, abdominal pain, dyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.44\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, dysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eordered but not done\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.45\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eweight loss\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003edistal esophageal spasm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.50\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.51\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, gas/bloating, dysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eIEM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.52\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003enausea/vomiting, dyspepsia, dumping syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.52\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edumping syndrome, gas/bloating, nausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.55\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eamyloid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edysphagia, gas/bloating, constipation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.56\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003echronic nausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edumping syndrome, gas/bloating, nausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot tested\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.60\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, dumping syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.61\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003econstipation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003econstipation, gas/bloating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.62\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, chronic abdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.68\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003edysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edysphagia, dumping syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal LES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.73\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003egas/bloating, dysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.76\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea, abdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1.79\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eamyloid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edyspepsia, rectal bleeding, pancreatic insufficiency\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e2.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ebloating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003egas/bloating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e2.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eabdominal pain, constipation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e2.40\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003edumping syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eabdominal pain, gas/bloating, dyspepsia, diarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e3.09\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGER\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eabdominal pain, nausea/vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eabnormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e3.77\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eamyloid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003enormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003enot ordered\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e5.43\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eAbbreviations:\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eIneffective Esophageal Motility: IEM\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eEsophagogastric Junction Outflow Obstruction: EGJOO\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003eDistal Esophageal Spasm: DES\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eIn those patients with symptoms of nausea and vomiting but with normal gastric emptying study, the sham feeding tests were all abnormal. There was no correlation between sham feeding result with symptoms of abdominal pain and GER.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eMedical and financial expenditure\u003c/h2\u003e\u003cp\u003eThe care after apparent vagus nerve injury required significant medical resources, including an average of 4.43 visits and 8.47 tests per patient to evaluate key GI symptoms.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003eSubgroup analysis\u003c/h2\u003e\u003cp\u003eAmong 53 included for this study, there are 9 (44.4%, n\u0026thinsp;=\u0026thinsp;4, female) patients included who were referred due to suspicion of amyloid involvement in GI tract. The average age of patients with amyloidosis is 67.12 years compared to 55.2 years in patients who had previous surgical procedures. Majority are white (88.9%, n\u0026thinsp;=\u0026thinsp;8) and the mean BMI was 23.9 kg/m\u003csup\u003e2\u003c/sup\u003e. The mean GI symptoms are dyspepsia (33.3%, n\u0026thinsp;=\u0026thinsp;3) and diarrhea (33.3%, n\u0026thinsp;=\u0026thinsp;3). The average weight loss from symptoms onset was 12.9 lb. (range: 0-50lb) compared to 25.3 lb. (range: 0-100lb) for patients with prior abdominal surgical history. 6 amyloidosis patients have positive sham feeding results. Only 4 patients have underwent gastric emptying scintigraphy and half of them are abnormal. The number of tests ordered for patients with amyloidosis is less than patients who developed vagus nerve injury after surgical procedures, 4 compared to 9.34, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison Of Patients Diagnosed with Amyloidosis with Patient Who Had Previous Abdominal Surgical History\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePatients with amyloidosis (n\u0026thinsp;=\u0026thinsp;9)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePatient with previous surgical history (n\u0026thinsp;=\u0026thinsp;44)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e67.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e55.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e44.4%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e59.1%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRace\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9 white\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e34 White\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2 Black\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eone Asian\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eone Hispanic\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5 did not disclose\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e23.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e28.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean weight loss (lb.)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12.86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGI symptoms\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003edyspepsia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3 (33.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7 (16%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ediarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3 (33.3%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11(25%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003enausea and vomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1 (11.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e20(45.55)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003edysphagia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1 (11.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8(18.2%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003egas/bloating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1 (11.1%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9(20.5%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003edumping syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6(13.6%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5(11.4%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eheartburn\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2(4.5%)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eothers\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4 (44.4%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAbnormal Gastric emptying scintigraphy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (50%, n\u0026thinsp;=\u0026thinsp;4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e19 (47.5%, n\u0026thinsp;=\u0026thinsp;40)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePositive sham feeding\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e66.7% (n\u0026thinsp;=\u0026thinsp;6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e63.7% (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAverage number of tests ordered after presumed insult\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe studied the characteristics of patients who underwent sham feeding study and the relationship between sham feeding results with GI symptoms, indication for sham feeding and medical resource usage. We have found out that in patient who had symptoms of nausea and vomiting, sham feeding is extremely sensitive to assess vagus nerve injury compared to gastric emptying scintigraphy, especially in patients who had prior abdominal surgery such as fundoplication and/or hiatal hernia repair. Sham feeding is a helpful tool to assist early diagnosis and potentially decreases the medical and financial expenditure associated with diagnosis process. Meanwhile, in patients with amyloidosis, sham feeding evaluation provides valuable information about vagus nerve involvement.\u003c/p\u003e\u003cp\u003ePrevious studies have shown that after anti-reflux surgery, 10\u0026ndash;20% of patients had signs of vagus nerve dysfunction[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Abnormal vagus function cannot be measured or evaluated directly. In the past, an indirect method has been developed to measure vagus dysfunction by measuring the response of plasma pancreatic polypeptide secretion to insulin-induced hypoglycemia, the insulin hypoglycemia-PP test[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eVagal nerve dysfunction was speculated to cause functional dyspepsia through antral dysmotility, impaired gastric accommodation and visceral hypersensitivity[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. This hypothesis was further validated by the result that vagal stimulation by sham feeding improves and even normalizes antral motility in functional dyspepsia patients[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Due to unspecific symptoms caused by vagal nerve injury, patients often underwent multiple testing to establish the diagnosis as shown in our study that the average number of tests are 9.3 in patients who have prior surgical history. Patients who presented with symptoms of nausea and vomiting have a very robust rate of abnormal sham feeding result compared to results of gastric emptying scintigraphy, thus is highly indictive of vagal nerve injury. Previous study showed some patients referred for anti-reflux surgery have evidence of abnormal vagus function that persists after surgery. Many patients with normal testing before surgery develop an abnormal test after surgery[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Though there is no study observing significant differences between surgical procedures with respect to the prevalence of vagus nerve injury[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], the percentage of patients with vagus nerve injury after intro(BM IV) was higher than after Nissen and Toupet fundoplication group[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Factors that potentially may increase the risk of vagus nerve injury during anti-reflux surgery include the presence of a large para-esophageal or axial hiatal hernia, previous abdominal surgery, severe esophagitis causing adhesions, poor visibility of the anatomy in the gastroesophageal region, anatomical variations of the vagus nerve, and limited experience with the procedure of the surgeon [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn patients diagnosed with amyloidosis with gastrointestinal symptoms, sham feeding would be helpful in detection of vagal nerve injury. In one study investigating the correlation of biopsy in amyloid patients and symptoms, 91.7% of patients demonstrated GI histopathologic positivity (paper forthcoming). The most common GI symptoms in patients with amyloidosis are abdominal pain, constipation, or diarrhea. Our study could help risk stratification and tailor treatment plan if there is suspicion of vagal nerve involvement. Octreotide was speculated to treat gastrointestinal sequelae from vagal nerve injury and has been used off-label to manage some symptoms in patient has severe dumping syndrome and refractory post-vagotomy diarrhea by inhibiting hormone secretion and slowing transit[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur research highlights the clinical implication of sham feeding in early diagnosis and management of GI symptoms especially in patients with prior foregut surgery or diagnosis of amyloidosis. Utilization of sham feeding could decrease significant medical and financial burden evaluating patients with symptoms after foregut surgery. Larger prospective studies are needed to better quantify the relationship between PP levels and gastric emptying in patients with prior foregut surgery who remain symptomatic.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eConsent to participation declaration: not applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFunding: not applicable.\u003c/p\u003e\n\u003cp\u003eClinical trial number: not applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest statement:\u003c/strong\u003e None\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eLin, T.M. and R.E. Chance, \u003cem\u003eCandidate hormones of the gut. VI. Bovine pancreatic polypeptide (BPP) and avian pancreatic polypeptide (APP).\u003c/em\u003e Gastroenterology, 1974. \u003cstrong\u003e67\u003c/strong\u003e(4): p. 737-8.\u003c/li\u003e\n\u003cli\u003eSchwartz, T.W., et al., \u003cem\u003eVagal, cholinergic regulation of pancreatic polypeptide secretion.\u003c/em\u003e J Clin Invest, 1978. \u003cstrong\u003e61\u003c/strong\u003e(3): p. 781-9.\u003c/li\u003e\n\u003cli\u003eBalaji, N.S., et al., \u003cem\u003eA safe and noninvasive test for vagal integrity revisited.\u003c/em\u003e Arch Surg, 2002. \u003cstrong\u003e137\u003c/strong\u003e(8): p. 954-8; discussion 958-9.\u003c/li\u003e\n\u003cli\u003eLindeboom, M.Y., et al., \u003cem\u003eGastric emptying and vagus nerve function after laparoscopic partial fundoplication.\u003c/em\u003e Ann Surg, 2004. \u003cstrong\u003e240\u003c/strong\u003e(5): p. 785-90.\u003c/li\u003e\n\u003cli\u003evan Rijn, S., et al., \u003cem\u003eEffect of Vagus Nerve Integrity on Short and Long-Term Efficacy of Antireflux Surgery.\u003c/em\u003e Am J Gastroenterol, 2016. \u003cstrong\u003e111\u003c/strong\u003e(4): p. 508-15.\u003c/li\u003e\n\u003cli\u003eSchwartz, T.W., \u003cem\u003ePancreatic polypeptide: a hormone under vagal control.\u003c/em\u003e Gastroenterology, 1983. \u003cstrong\u003e85\u003c/strong\u003e(6): p. 1411-25.\u003c/li\u003e\n\u003cli\u003eGilja, O.H., et al., \u003cem\u003eImpaired accommodation of proximal stomach to a meal in functional dyspepsia.\u003c/em\u003e Dig Dis Sci, 1996. \u003cstrong\u003e41\u003c/strong\u003e(4): p. 689-96.\u003c/li\u003e\n\u003cli\u003eLunding, J.A., et al., \u003cem\u003eVagal activation by sham feeding improves gastric motility in functional dyspepsia.\u003c/em\u003e Neurogastroenterol Motil, 2008. \u003cstrong\u003e20\u003c/strong\u003e(6): p. 618-24.\u003c/li\u003e\n\u003cli\u003eDeVault, K.R., et al., \u003cem\u003eEvaluation of vagus nerve function before and after antireflux surgery.\u003c/em\u003e Journal of Gastrointestinal Surgery, 2004. \u003cstrong\u003e8\u003c/strong\u003e(7): p. 881-887.\u003c/li\u003e\n\u003cli\u003eMackie, C.R., S.A. Jenkins, and M.N. Hartley, \u003cem\u003eTreatment of severe postvagotomy/postgastrectomy symptoms with the somatostatin analogue octreotide.\u003c/em\u003e Br J Surg, 1991. \u003cstrong\u003e78\u003c/strong\u003e(11): p. 1338-43.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table 1","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"digestive-diseases-and-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ddsj","sideBox":"Learn more about [Digestive Diseases and Sciences](http://link.springer.com/journal/10620)","snPcode":"10620","submissionUrl":"https://submission.nature.com/new-submission/10620/3","title":"Digestive Diseases and Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"sham feeding, vagal nerve function, foregut surgery, gastroparesis","lastPublishedDoi":"10.21203/rs.3.rs-7350147/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7350147/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground:\u003c/h2\u003e\u003cp\u003eVagal nerve injury can cause non-specific symptoms and is challenging to assess. Pancreatic polypeptide (PP) release after sham feeding is a surrogate marker of vagal function. This study evaluated vagal integrity using sham feeding-induced PP measurement, and examined associations between symptoms, PP levels, and gastric emptying.\u003c/p\u003e\u003ch2\u003eMethod:\u003c/h2\u003e\u003cp\u003eThis was a retrospective study of patients who underwent sham feeding from 2018 to present. We collected demographic and clinical data, sham feeding results, indication for study, gastric emptying data. A 50% increase in PP level within 30 mins compared to baseline was considered normal. A gastric emptying scan was classified as delayed if\u0026thinsp;\u0026lt;\u0026thinsp;75% of the material emptied at 4 hours.\u003c/p\u003e\u003ch2\u003eResults:\u003c/h2\u003e\u003cp\u003e53 patients were included (58.5% women) with a mean age of 57.2 years. The main GI symptoms were nausea and vomiting (21, 40.0%) and diarrhea (14, 26.4%). 36 of 53 patients had a history of abdominal surgery, with Nissen fundoplication including open and laparoscopic being the most common surgeries (10, 27.8%). The fold of PP changes between abnormal and normal groups are significantly different (p\u0026thinsp;=\u0026thinsp;0). In 23 patients with symptoms of nausea and vomiting, symptoms of nausea and vomiting were found to have a robust correlation with a positive sham feeding result (21, 91.3%), compared with gastric emptying scintigraphy (14, 60.9%).\u003c/p\u003e\u003ch2\u003eConclusion:\u003c/h2\u003e\u003cp\u003eSham feeding is consistently abnormal in patients with predominant symptoms of nausea and vomiting while the correlation between gastric scintigraphy result and gastroparesis symptoms was not significant. Sham feeding may be a valuable test when assessing patients with symptoms of nausea and vomiting.\u003c/p\u003e","manuscriptTitle":"Assessment of Vagus Nerve Injury Through Sham Feeding","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-26 14:01:28","doi":"10.21203/rs.3.rs-7350147/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-13T05:51:23+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-09-10T23:55:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"47318395267770854860016975938072780789","date":"2025-08-21T01:17:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"130662568268825845829742872492539271272","date":"2025-08-18T22:41:20+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"162980223824522254803029185683846375029","date":"2025-08-18T21:45:09+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-18T21:39:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-18T19:21:29+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-13T13:41:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"Digestive Diseases and Sciences","date":"2025-08-12T01:01:47+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"digestive-diseases-and-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ddsj","sideBox":"Learn more about [Digestive Diseases and Sciences](http://link.springer.com/journal/10620)","snPcode":"10620","submissionUrl":"https://submission.nature.com/new-submission/10620/3","title":"Digestive Diseases and Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5bc56cf1-e4ca-40a2-a0bd-a22db76de66a","owner":[],"postedDate":"August 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-12-07T06:23:11+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-26 14:01:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7350147","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7350147","identity":"rs-7350147","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}