Characterization of gastric dysfunction after fundoplication using body surface gastric mapping.

BACKGROUND: Adverse gastric symptoms persist in up to 20% of fundoplication operations completed for gastroesophageal reflux disease, causing significant morbidity and driving the need for revisional procedures. Noninvasive techniques to assess the mechanisms of persistent postoperative symptoms are lacking. This study aimed to investigate gastric myoelectrical abnormalities and symptoms in patients after fundoplication using a novel noninvasive body surface gastric mapping (BSGM) device. METHODS: Patients with a previous fundoplication operation and ongoing significant gastroduodenal symptoms and matched controls were included. BSGM using Gastric Alimetry (Alimetry Ltd) was employed, consisting of a high-resolution 64-channel array, validated symptom-logging application, and wearable reader. RESULTS: A total of 16 patients with significant chronic symptoms after fundoplication were recruited, with 16 matched controls. Overall, 6 of 16 patients (37.5%) showed significant spectral abnormalities defined by unstable gastric myoelectrical activity (n = 2), abnormally high gastric frequencies (n = 3), or high gastric amplitudes (n = 1). Patients with spectral abnormalities had higher Patient Assessment of Upper Gastrointestinal Disorders-Symptom Severity Index scores than those of patients without spectral abnormalities (3.2 [range, 2.8-3.6] vs 2.3 [range, 2.2-2.8], respectively; P = .024). Moreover, 7 of 16 patients (43.8%) had BSGM test results suggestive of gut-brain axis contributions and without myoelectrical dysfunction. Increasing Principal Gastric Frequency Deviation and decreasing Rhythm Index scores were associated with symptom severity (r > .40; P < .05). CONCLUSION: A significant number of patients with persistent postfundoplication symptoms displayed abnormal gastric function on BSGM testing, which correlated with symptom severity. Our findings advance the pathophysiologic understanding of postfundoplication disorders, which may inform diagnosis and patient selection for medical therapy and revisional procedures.

Empowering Pacific Patients on the Weight Loss Surgery Pathway: A Co-designed Evaluation Study.

PURPOSE: Despite having the highest medical needs by population for weight loss treatment, Pacific patients in Aotearoa New Zealand face substantial levels of attrition in publicly funded weight loss surgery programs. In collaboration with the Auckland City Hospital bariatric surgery team, a Pacific-led preoperative weight loss surgery program was co-designed, delivered, and evaluated between 2020 and 2023. MATERIALS AND METHODS: This was a single-arm, prospective co-designed evaluation study that took place at Auckland City Hospital in Aotearoa New Zealand. Participants were Pacific patients (n = 14) referred to the weight loss surgery program. Survey and video diaries were analyzed to determine if the program had the potential to increase Pacific patient retention through the preoperative stage of weight loss surgery, increase surgery completion rates, and improve the quality of treatment experiences. RESULTS: Nine out of 14 participants attended all preoperative sessions. Six participants subsequently underwent weight loss surgery. Program components that had positive impacts on patient success and satisfaction were accessibility, information quality, having Pacific role models, cultural safety, and the group support system. The patients found the program to be culturally anchored and there was support for the implementation of the program going forward. CONCLUSION: This study demonstrated how a culturally anchored intervention can increase patient retention for those patients who may not respond to mainstream treatment. Adjusting existing preoperative weight loss surgery programs to integrate Pacific-led models of healthcare has the potential to increase Pacific patient resiliency to follow through with surgery.

Impact of Bariatric Surgery on Unplanned Hospital Admissions for Infection.

PURPOSE: Both obesity and type 2 diabetes are associated with an increased risk of skin and soft tissue (SSTI), urinary tract, and lower respiratory tract infections but it is not clear whether the incidence of such infections is reduced after bariatric surgery. MATERIALS AND METHODS: In people accepted onto our publicly funded bariatric program, we recorded unplanned admissions to public hospitals over a median follow-up of 4.5 years in those successfully undergoing surgery and in those who withdrew from the program. Rates of admission for the composite outcome (SSTI, urinary tract, or lower respiratory infection) were compared. RESULTS: Of 774 people accepted onto the program, 49% underwent surgery. Infections accounted for 27% of unplanned admissions in those not completing surgery and 13% of those who underwent surgery (p < 0.001). The rate of admission was 60% lower in people who underwent surgery than those who did not: 4.3 vs 12.2 per 100 patient-years (P < 0.002), a difference maintained across 8 years' follow-up. The impact of surgery was independent of enrolment age, BMI, or diabetes and smoking status. Of the three types of infection in the composite outcome, SSTI were the most prevalent and showed the greatest reduction (p < 0.0001). The median day stay for infection was 0.5 day less in those who underwent surgery (p < 0.01). CONCLUSIONS: Hospitalization for these three infectious diseases in people undergoing bariatric surgery was lower than that in people enrolled in the bariatric program but not completing surgery. The effect was greatest for SSTI, and sustained to at least 8 years.

Insulin use and new diabetes after acceptance for bariatric surgery: comparison of outcomes after completion of surgery or withdrawal from the program.

INTRODUCTION: In people accepted onto a bariatric surgery program we compared diabetes-related outcomes in those who completed surgery with those who withdrew before having surgery-examining rates of insulin use in people with type 2 diabetes (T2D), and rates of incident diabetes in people without pre-existing T2D. RESEARCH DESIGN AND METHODS: 771 people were accepted onto the program. 463 people (60%) had T2D at referral, of which 48% completed surgery and 52% withdrew. Of 308 people without T2D at referral, 49% completed surgery, and 51% withdrew. Rates of insulin use and incident diabetes were compared by Kaplan-Meier analyses. Among those with pre-existing T2D, we examined rates of remission and relapse after surgery. RESULTS: People without T2D who withdrew from the program had higher mean body mass index and glycated hemoglobin levels than those completing surgery (p<0.005). The rate of incident diabetes at 5 years was 19% in those who withdrew versus 0% in those completing surgery (p<0.001). 30% of people with T2D were taking insulin at referral and all stopped insulin after surgery. During follow-up, the rate of insulin (re)introduction was lower in those who completed surgery (8% vs 26% at 5 years, p<0.001). Of those with T2D who completed surgery, 80% had remission, but 34% had relapsed by 5 years. Diabetes relapse was associated with less weight loss after surgery, a longer duration of T2D and previous insulin use. CONCLUSIONS: Despite a high relapse rate, people with T2D who completed surgery had lower insulin use at 5 years than those withdrawing from the program. In people without T2D, bariatric surgery prevented incident diabetes. People without T2D who withdrew from the program were at greater risk of diabetes, suggesting those who could benefit the most in terms of T2D prevention are not completing bariatric surgery.

Safety and Utility of Liver Biopsy During Bariatric Surgery in the New Zealand Setting.

BACKGROUND: Asymptomatic liver disease is common in bariatric patients and can be diagnosed with intraoperative biopsy. This study aimed to establish the risk-benefit profile of routine liver biopsy, prevalence of clinically significant liver disease, relationship between liver pathology and body mass index, and compare outcomes between ethnic groups. METHODS: This retrospective cohort study included all patients who had index bariatric surgery at Auckland City Hospital between 2009 and 2016. Diagnosis of liver disease was based on intraoperative biopsy histology. Outcomes included safety (biopsy-related complication) and utility (liver pathology meeting criteria for referral). Liver pathology and referral rates were compared between ethnic groups. RESULTS: Of 335 bariatric surgery patients, 234 (70%) underwent intraoperative liver biopsy. There were no biopsy-related complications. Histological findings were as follows: normal 25/234 (11%), non-alcoholic fatty liver disease (NAFLD) 207/234 (88%), and other pathological findings in 35/234 (15%). Histological finding meeting referral criteria was present in 22/234 (9%). Of these, 12/22 (55%) were referred. Number needed to biopsy to identify histology meeting referral criteria: n = 11. Maori had a similar NAFLD rate to non-Maori [51/56 versus 156/178, p = 0.48]. Pasifika patients had a higher rate than non-Pasifika [39/40 versus 168/194, p = 0.049]. Maori and Pasifika patients had similar referral rates to non-Maori and non-Pasifika [2/3 versus 5/9, p = 0.73; 2/2 versus 5/10, p = 0.19]. CONCLUSIONS: Intraoperative liver biopsy during bariatric surgery is safe and identified liver disease in 89%, with 9% meeting referral criteria. Pasifika patients have a higher rate of NAFLD than non-Pasifika.

Slow-wave coupling across a gastroduodenal anastomosis as a mechanism for postsurgical gastric dysfunction: evidence for a "gastrointestinal aberrant pathway".

Postsurgical gastric dysfunction is common, but the mechanisms are varied and poorly understood. The pylorus normally acts as an electrical barrier isolating gastric and intestinal slow waves. In this report, we present an aberrant electrical conduction pathway arising between the stomach and small intestine, following pyloric excision and surgical anastomosis, as a novel disease mechanism. A patient was referred with postsurgical gastroparesis following antrectomy, gastroduodenostomy, and vagotomy for peptic ulceration. Scintigraphy confirmed markedly abnormal 4-h gastric retention. Symptoms included nausea, vomiting, postprandial distress, and reflux. Intraoperative, high-resolution electrical mapping was performed across the anastomosis immediately before revision gastrectomy, and the resected anastomosis underwent immunohistochemistry for interstitial cells of Cajal. Mapping revealed continuous, stable abnormal retrograde slow-wave propagation through the anastomosis, with slow conduction occurring at the scar (4.0 ± 0.1 cycles/min; 2.5 ± 0.6 mm/s; 0.26 ± 0.15 mV). Stable abnormal retrograde propagation continued into the gastric corpus with tachygastria (3.9 ± 0.2 cycles/min; 1.6 ± 0.5 mm/s; 0.19 ± 0.12 mV). Histology confirmed ingrowth of atypical ICC through the scar, defining an aberrant pathway enabling transanastomotic electrical conduction. In conclusion, a "gastrointestinal aberrant pathway" is presented as a novel proposed cause of postsurgical gastric dysfunction. The importance of aberrant anastomotic conduction in acute and long-term surgical recovery warrants further investigation.NEW & NOTEWORTHY High-resolution gastric electrical mapping was performed during revisional surgery in a patient with severe gastric dysfunction following antrectomy and gastroduodenostomy. The results revealed continuous propagation of slow waves from the duodenum to the stomach, through the old anastomotic scar, and resulting in retrograde-propagating tachygastria. Histology showed atypical interstitial cells of Cajal growth through the anastomotic scar. Based on these results, we propose a "gastrointestinal aberrant pathway" as a mechanism for postsurgical gastric dysfunction.

Variation in public-funded bariatric surgery intervention rate by New Zealand region.

Inequitable access to bariatric surgery by geographical region has been reported internationally, but comparable data on provision of bariatric surgery have not previously been reported in New Zealand. We examined allocated funding and provision of bariatric surgery amongst different regions in New Zealand in the 2013/14 year, and found that there was large variation in both. This highlights that public funded bariatric surgery needs to take into account population prevalence of morbid obesity to reduce inequities by geographical region.

Pre-operative Bariatric Clinic Attendance Is a Predictor of Post-operative Clinic Attendance and Weight Loss Outcomes.

AIM: Our primary aim was to determine whether non-attendance at pre-operative clinics were associated with non-attendance at post-operative clinics and its influence on weight loss. We also sought to examine the relationship between gender, ethnicity and post-operative clinic attendance with respect to weight loss post-bariatric surgery. METHODS: A retrospective audit was performed for patients undertaking the bariatric surgery program at the Auckland City Hospital between 2013 and 2016. RESULTS: One hundred and eighty-four patients completed our program, with a mean age of 46.1 years. Mean weight at commencement was 133.3 kg, with a BMI of 47.4. At 2 years follow-up (n = 143), excess weight loss was 70.8% following RYGB and 68.0% following LSG (p = 0.5743). More patients attended all pre-operative than post-operative clinics (67.4% vs 37.5% p = < 0.001). One pre-operative clinic non-attendance was associated with less weight loss at 2 years and it increases the risk of missing at least 50% of post-operative clinics with a risk ratio of 2.73, p = 0.005. Non-attendance of at least 50% of post-operative clinics was also associated with less weight loss at 2 years (33.4 kg vs 44.3 kg, p = 0.040). Although Maori and Pacific Islanders more frequently missed > 50% of post-operative clinics, weight loss was similar between European, Maori and Pacific Islander populations (2-year weight loss 44.2 kg vs 40.74 kg vs 44.1 kg, respectively, p = 0.8192). CONCLUSION: Pre-operative clinic non-attendance helps predict post-operative clinic non-attendance. Missing any pre-operative clinics and at least 50% of scheduled post-operative clinics is associated with poorer weight loss outcomes.

Attrition after Acceptance onto a Publicly Funded Bariatric Surgery Program.

BACKGROUND: Factors such as ethnicity, gender, and socioeconomic status may play a role in both access to and attrition from bariatric programs before surgery is undertaken. New Zealand (NZ) has high rates of obesity in its Pacific population and the indigenous Maori. These groups also experience poorer health outcomes and therefore have the greatest need for surgery. METHODOLOGY: A retrospective cross-sectional study of 704 people referred for and accepted onto a publicly funded bariatric surgery from 2007 to 2016. The demographic and clinical features of two groups were compared: those that completed surgery successfully (n = 326) and those that dropped out of the program before surgery (n = 378). We also attempted to identify factors associated with attrition. RESULTS: The attrition rate was high (54%), with a significant difference according to gender (men 66% vs 45% women, p < 0.001) and ethnicity (39% in NZ Europeans, 50% in Maori, and 73% in Pacific patients, p < 0.001). Two out of three European women proceeded to surgery, but fewer than one in seven Pacific men. Attrition was associated with having a higher mean BMI and being a smoker. Logistic regression modeling showed that while employment seemed to be protective against attrition for NZ Europeans (p < 0.004), it was not for Pacific patients. CONCLUSIONS: While there was no obvious bias in rates of referral, there is clearly a need for better ways to support Maori and Pacific people, and men in particular, to complete bariatric surgery. Further research is needed to clarify the socio-economic and cultural barriers that underlie this phenomenon.

Correction to: Attrition after Acceptance onto a Publicly Funded Bariatric Surgery Program.

Unfortunately, the original version of this article contained an error. The Methods section's first sentence and Table 1 both mistakenly contained the letters XXXX in place of the district health board and hospital city names.

Randomized clinical trial of expressive writing on wound healing following bariatric surgery.

OBJECTIVE: Writing emotionally about upsetting life events (expressive writing) has been shown to speed healing of punch-biopsy wounds compared to writing objectively about daily activities. We aimed to investigate whether a presurgical expressive writing intervention could improve surgical wound healing. METHOD: Seventy-six patients undergoing elective laparoscopic bariatric surgery were randomized either to write emotionally about traumatic life events (expressive writing) or to write objectively about how they spent their time (daily activities writing) for 20 min a day for 3 consecutive days beginning 2 weeks prior to surgery. A wound drain was inserted into a laparoscopic port site and wound fluid analyzed for proinflammatory cytokines collected over 24 hr postoperatively. Expanded polytetrafluoroethylene tubes were inserted into separate laparoscopic port sites during surgery and removed after 14 days. Tubes were analyzed for hydroxyproline deposition (the primary outcome), a major component of collagen and marker of healing. Fifty-four patients completed the study. RESULTS: Patients who wrote about daily activities had significantly more hydroxyproline than did expressive writing patients, t(34) = -2.43, p = .020, 95% confidence interval [-4.61, -0.41], and higher tumor necrosis factor-alpha, t(29) = -2.42, p = .022, 95% confidence interval [-0.42, -0.04]. Perceived stress significantly reduced in both groups after surgery. CONCLUSIONS: Expressive writing prior to bariatric surgery was not effective at increasing hydroxyproline at the wound site 14 days after surgery. However, writing about daily activities did predict such an increase. Future research needs to replicate these findings and investigate generalizability to other surgical groups. (PsycINFO Database Record

Patterns of Abnormal Gastric Pacemaking After Sleeve Gastrectomy Defined by Laparoscopic High-Resolution Electrical Mapping.

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) is increasingly being applied to treat obesity. LSG includes excision of the normal gastric pacemaker, which could induce electrical dysrhythmias impacting on post-operative symptoms and recovery, but these implications have not been adequately investigated. This study aimed to define the effects of LSG on gastric slow-wave pacemaking using laparoscopic high-resolution (HR) electrical mapping. METHODS: Laparoscopic HR mapping was performed before and after LSG using flexible printed circuit arrays (64-96 electrodes; 8-12 cm2; n = 8 patients) deployed through a 12 mm trocar and positioned on the gastric serosa. An additional patient with chronic reflux, nausea, and dysmotility 6 months after LSG also underwent gastric mapping while undergoing conversion to gastric bypass. Slow-wave activity was quantified by propagation pattern, frequency, velocity, and amplitude. RESULTS: Baseline activity showed exclusively normal propagation. Acutely after LSG, all patients developed either a distal unifocal ectopic pacemaker with retrograde propagation (50%) or bioelectrical quiescence (50%). Propagation velocity was abnormally rapid after LSG (12.5 ± 0.8 vs baseline 3.8 ± 0.8 mm s-1; p = 0.01), whereas frequency and amplitude were unchanged (2.7 ± 0.3 vs 2.8 ± 0.3 cpm, p = 0.7; 1.7 ± 0.2 vs 1.6 ± 0.6 mV, p = 0.7). In the patient with chronic dysmotility after LSG, mapping also revealed a stable antral ectopic pacemaker with retrograde rapid propagation (12.6 ± 4.8 mm s-1). CONCLUSION: Resection of the gastric pacemaker during LSG acutely resulted in aberrant distal ectopic pacemaking or bioelectrical quiescence. Ectopic pacemaking can persist long after LSG, inducing chronic dysmotility. The clinical and therapeutic significance of these findings now require further investigation.

Differential Acute Impacts of Sleeve Gastrectomy, Roux-en-Y Gastric Bypass Surgery and Matched Caloric Restriction Diet on Insulin Secretion, Insulin Effectiveness and Non-Esterified Fatty Acid Levels Among Patients with Type 2 Diabetes.

BACKGROUND: Bariatric surgery is an increasingly common option for control of type 2 diabetes (T2D) and obesity. Mechanisms underlying rapid improvement of T2D after different types of bariatric surgery are not clear. Caloric deprivation and altered levels of non-esterified fatty acid (NEFA) have been proposed. This study examines how sleeve gastrectomy (SG), Roux-en-Y gastric bypass (GBP) or matched hypocaloric diet (DT) achieves improvements in T2D by characterising components of the glucose metabolism and NEFA levels before and 3 days after each intervention. METHODS: Plasma samples at five time points during oral glucose tolerance test (OGTT) from subjects with T2D undergoing GBP (N = 11) or SG (N = 12) were analysed for C-peptide, insulin and glucose before surgery and 3-day post-intervention or after DT (N = 5). Fasting palmitic, linoleic, oleic and stearic acid were measured. C-peptide measurements were used to model insulin secretion rate (ISR) using deconvolution. RESULTS: Subjects who underwent GBP surgery experienced the greatest improvement in glycaemia (median reduction in blood glucose (BG) from basal by 29 % [IQR -57, -18]) and the greatest reduction in all NEFA measured. SG achieved improvement in glycaemia with lower ISR and reduction in all but palmitoleic acid. DT subjects achieved improvement in glycaemia with an increase in ISR, 105 % [IQR, 20, 220] and stearic acid. CONCLUSIONS: GBP, SG and DT each improve glucose metabolism through different effects on pancreatic beta cell function, insulin sensitivity and free fatty acids.

Crohn's disease presenting as gastric outlet obstruction.

We present a unique presentation of Crohn's disease in a 25-year-old male with a 3-month history of progressive gastric outlet obstruction symptoms including reflux, vomiting, postprandial pain and weight loss, with no other symptoms. Multiple imaging investigations as well as gastroscopic biopsies revealed a non-specific prepyloric lesion, without evidence of malignancy. A distal gastrectomy was performed. Subsequent histological evaluation revealed gastroduodenal Crohn's disease. Follow-up revealed no evidence of disease elsewhere in the gastrointestinal system or systemically. While it is not uncommon for Crohn's disease to involve the stomach and duodenum, it is rare for gastroduodenal disease to be the initial presentation. Isolated gastroduodenal Crohn's disease typically presents with non-specific gastritis-like symptoms over a number of years. This patient had a unique course of Crohn's disease with rapid onset of symptoms, predominantly relating to gastric outlet obstruction and no prior or subsequent history of gastrointestinal symptoms.

Lower fetuin-A, retinol binding protein 4 and several metabolites after gastric bypass compared to sleeve gastrectomy in patients with type 2 diabetes.

BACKGROUND: Bypass of foregut secreted factors promoting insulin resistance is hypothesized to be one of the mechanisms by which resolution of type 2 diabetes (T2D) follows roux-en-y gastric bypass (GBP) surgery. AIM: To identify insulin resistance-associated proteins and metabolites which decrease more after GBP than after sleeve gastrectomy (SG) prior to diabetes remission. METHODS: Fasting plasma from 15 subjects with T2D undergoing GBP or SG was analyzed by proteomic and metabolomic methods 3 days before and 3 days after surgery. Subjects were matched for age, BMI, metformin therapy and glycemic control. Insulin resistance was calculated using homeostasis model assessment (HOMA-IR). For proteomics, samples were depleted of abundant plasma proteins, digested with trypsin and labeled with iTRAQ isobaric tags prior to liquid chromatography-tandem mass spectrometry analysis. Metabolomic analysis was performed using gas chromatography-mass spectrometry. The effect of the respective bariatric surgery on identified proteins and metabolites was evaluated using two-way analysis of variance and appropriate post-hoc tests. RESULTS: HOMA-IR improved, albeit not significantly, in both groups after surgery. Proteomic analysis yielded seven proteins which decreased significantly after GBP only, including Fetuin-A and Retinol binding protein 4, both previously linked to insulin resistance. Significant decrease in Fetuin-A and Retinol binding protein 4 after GBP was confirmed using ELISA and immunoassay. Metabolomic analysis identified significant decrease of citrate, proline, histidine and decanoic acid specifically after GBP. CONCLUSION: Greater early decrease was seen for Fetuin-A, Retinol binding protein 4, and several metabolites after GBP compared to SG, preceding significant weight loss. This may contribute to enhanced T2D remission observed following foregut bypass procedures.

Bariatric surgery makes dramatic difference to health-related quality of life.

AIM: To explore the impact of bariatric surgery on health-related quality of life (HRQoL). METHODS: An audit of patients referred for bariatric procedures. Patients completed Short Form-36 questionnaires at their first pre-operative clinic and at their 6-month follow up appointment after surgery. SF-36 scores were compared with standard parametric tests. RESULTS: 40 patients completed baseline SF-36 questionnaires and underwent bariatric surgery, 28 were surveyed again 6 months post-procedure during the audit period between December 2008 and December 2010. Twenty-three patients underwent laparoscopic Roux-en-Y gastric bypass and five underwent laparoscopic sleeve gastrectomy. The patients were predominantly New Zealand European, female, with a body mass index greater than 40 kg/m2. Significant improvements in health-related quality of life were observed. The physical and mental component summary scores were initially well below the population norms, but increased to the norm 6 months after surgery. CONCLUSION: The HRQoL of morbidly obese patients significantly improves after bariatric surgery. Services including the SF-36 in their measurement armamentarium can demonstrate the Service's impact on patient-perceived outcomes in addition to clinically-focused outcomes.

Indigenous child health in New Zealand: some surgical issues.

New Zealand Maori make up nearly 15% of the population of New Zealand, and their population has increased significantly in the last 20 years. Because of this, the average age of Maori is only 22.7 years with 35% of Maori aged 15 years or less. In spite of this youthful profile, the Maori population has high health needs with trauma, ear disease, respiratory disease and infectious diseases as significant causes of hospitalisation and death. The role of surgery in the management of three potentially preventable but significant health issues affecting Maori children - trauma, cutaneous sepsis (cellulitis and superficial abscess) and obesity - is reviewed.