Society: SSAT

Background
The aim of this study was to assess the association between interval between nCRT and
surgery and oncological and surgical outcomes in esophageal cancer patients.

Methods:
Pubmed, Embase and Cochrane data base were searched to identify eligible studies from
their inception to December 31, 2021 and divided into early and delayed surgery group. A
total of 19 studies with 12 retrospective cohort study, one randomized control trial and 6
data base registry study were included. A total of 13600 participants with 6395 participants
in early group and 7205 participants in delayed group were analyzed.

Results:
Pooled analysis of cohort studies comparing delayed surgery versus early surgery
showed no difference in OS (Hazard ratio (HR) 1.03 95% CI 0.91,1.16), pCR rate(Odds
Ratio (OR) 0.98, 95% CI 0.80, 1.20), R0 resection rate(OR 0.90, 95% CI 0.55, I.45;
I2=43%), perioperative mortality(OR1.03, 95% CI 0.59, 1.77; I2=0%), pulmonary (OR 1.26
95% CI 0.97,1.64; I2=22%) or major complication rate (OR 1.29, 95% CI 0.96, 1.73;
I2=29%) but was however associated with an increased anastomotic leak rate(OR 1.48,
95%CI 1.11,1.97). Mean while pooled assessment of data base registry studies showed
Delayed surgery resulted in increased pCR rate (OR 1.12, 95%CI 1.01, 1.24) which
however failed to translate to increased overall survival(HR 1.01, 95%CI 0.92 , 1.10; I2
=0%). But delayed surgery was associated with increased perioperative mortality(OR 1.35,
95% CI 1.07, 1.69; I2=15%), and major complication rate (OR 1.55; 95% CI 1.20, 2.01 I2=
26%)compared to early surgery.
Conclusion:
Delayed surgery produces equivalent oncological and surgical outcome except increased
anastomotic leak rates in high volume center. However, the result should be interpreted
with caution because of contradictory results between cohort studies and data base
registry studies.

Introduction
Conversion gastrectomy is increasingly being considered for gastric cancer peritoneal metastases (GCPM) patients who have good response to intraperitoneal paclitaxel (IP-PTX) with systemic therapy. However, the outcomes of surgery are unclear. Our study aimed to evaluate surgical outcomes and prognostic factors for conversion surgery.
Methods
Patients with GCPM were recruited for a prospective phase II trial and received IP-PTX with oral capecitabine and intravenous oxaliplatin (XELOX) in 21-day cycles. Those with good response to chemotherapy, had negative peritoneal fluid cytology with no extraperitoneal metastases and no carcinomatosis peritonei on re-look diagnostic laparoscopy underwent conversion gastrectomy. Primary outcome was overall survival (OS) and secondary endpoint were morbidity and especially those with Clavien-Dindo IIIb & Above.
Results
Of 64 patients with synchronous GCPM, 20 (31.3%) underwent conversion gastrectomy. Median operative time was 316 minutes (IQR 279-368) and median length of stay was 9 days (IQR 7-15). Distal gastrectomy was performed in 45% (9/20) while 55% (11/20) underwent total gastrectomy, with 85% (17/20) performed as open procedure. No combined organ resection or 30-day mortality was noted. Median lymph node harvest was 37 (IQR 23-44) and R0 resection margin was achieved in 65% (13/20) of patients but did not significantly influence median OS (R0 vs. R1-2, median OS; 29.5 vs. 20.7 months, p=0.442). Overall morbidity was 35% (7/20) & major morbidity reported in 10% (2/20) of patients who underwent re-operation for duodenal stump leak and bleeding. The overall 12-month OS was 85% and 24-months OS was 50%. Patients with poorer response to pre-operative therapy (tumour response grading [TRG] <3, p=0.082) and presence of LVI (p=0.057) were found to be associated with OS <24 months although significance was not reached. On survival analysis, median OS for patients with good response to pre-operative treatment (TRG <3) and those who did not (TRG=3) were 28.1 months and 16.0 months respectively (TRG<3, HR 0.085, 95% CI 0.016-0.44).
Conclusions
Conversion gastrectomy is a safe and feasible option for select GCPM patients following IP-PTX with systemic treatment. Response to pre-operative treatment was a significant predictor in overall survival after conversion surgery.

Background
Endoscopic sleeve gastroplasty (ESG) is a minimally invasive intervention to address obesity and associated comorbidities. Previous studies have shown variable outcomes following bariatric surgery for patients who are privately insured, publicly insured, or self-pay. Differences include higher excess weight loss (%EWL) and earlier loss to follow up in self-pay patients, with variability in comorbidity resolution and complications. In this study we aim to review our institutional outcomes following ESG by payer.

Methods
A retrospective review of a prospective bariatric quality database included all patients who underwent ESG between 6/2016 and 10/2022 at a single institution. Post-procedure outcomes, including %EWL, comorbidity resolution, and complications were collected and compared by payer status. Group comparisons were made using two-tailed Wilcoxon rank-sum and Fisher’s exact test.

Results
During the study period, 57 patients underwent ESG; 22 (38.6%) were insured and 35 (61.4%) were self-pay. Of the 22 insured patients, 16 (72.7%) were MERIT trial participants and 6 (27.3%) were privately insured. There were no significant demographic differences between the three groups, including starting BMI. Comorbidities differed in more hypertensive trial patients compared to privately insured patients (56.3% vs 0%, p=0.027) and more diabetic trial patients compared to self-pay or privately insured patients (37.5% vs 8.6% vs 0%, p=0.025). Preoperative rates of smoking, hyperlipidemia, obstructive sleep apnea and GERD did not differ significantly between groups. There were no significant differences in number of endosutures, OR time, estimated blood loss, length of stay, postoperative hemorrhage, return to OR, or 30-day outcomes including ED visits, readmission, death, or treatment for dehydration between groups. Trial participants had significantly longer median follow-up at 29 months compared to 9 months for private insurance and 6 months for self-pay, p=0.001. Median %EWL was greater in insured patients (n=4, all MERIT trial) compared to self-pay patients (n=4) at the 4-year postoperative timepoint only (-39.2±20.6% vs +9.4±14.0%, p=0.021). Self-pay patients had weight regain beyond consultation weight at the 4-year postoperative timepoint [Fig 1]. There were no statistically significant differences in HbA1c, diabetes, obstructive sleep apnea, GERD, hyperlipidemia, or hypertension between groups at 6-month, 1-year, 2-year, or 3-year postoperative timepoints.

Conclusion
Following ESG, excess weight loss is sustained up to 2-years postop regardless of payer, and up to 4-years postop in insured patients. Differences in %EWL by payer may include more sustained %EWL at 4-year postop in insured patients than in self-pay patients.

Purpose: Since 2011, nationally-recognized guidelines have recommended the use of intraoperative esophagogastroduodenoscopy (iEGD) during minimally invasive heller myotomy (MHM) to detect intraoperative leaks and prevent esophageal narrowing. Data regarding the application of these guidelines have not been reported. The purpose of this study is to evaluate the frequency of guideline adherence and rates of complications in patients undergoing MHM with and without iEGD.
Methods: The 2011-2020 National Surgical Quality Improvement Program (NSQIP) registry was utilized to evaluate patients undergoing MHM with or without iEGD. Trends, perioperative outcomes, and 30-day complications were examined using univariable analysis and multivariable regression.
Results: A total of 4,631 MHM patients were identified; 895 (19.3%) with concomitant iEGD, and 3735 (80.7%) without iEGD. Patient demographics including age, body mass index, gender, and race/ethnicity were similar between groups (all p>0.05). In patient undergoing iEGD, operative time was longer 150 ± 65 minutes vs 137 ± 58 minutes (p<0.001), but there was no difference in mean length of stay 2.0 ± 2.7 days vs 1.7 ± 4.1 days (p=0.052), or overall complication rate 50 (5.6%) vs 197 (5.3%) (p=0.708). The frequency of iEGD during MHM did not increase during the study period (Figure 1, p=0.658). Postoperatively, fewer iEGD patients suffered from pneumonia 2 (0.2%) vs 36 (1.0%), p=0.027, which remained statistically significant after multivariable regression (OR 0.191, 95% CI 0.045-0.808, p=0.024).
Conclusion: Despite 10 years of national guidelines encouraging the use of intraoperative EGD during minimally invasive heller myotomy, practice patterns have not appeared to change. This robust database of 30-day outcomes suggests iEGD is associated with decreased postoperative pneumonia, so further efforts to promote adherence to the guidelines may be warranted.

Trends if iEGD in MHM over 10 years

Introduction
Esophagectomy is a complex procedure performed for malignant and benign conditions. Procedural variations exist (including open vs laparoscopic vs robotic, two-stage Ivor-Lewis vs three-stage McKeown), but all involve the formation of a largely-thoracic gastric conduit. These may be associated with conduit dysfunction, early and/or persistent delayed gastric emptying, reflux and pain with no mechanical cause. There is emerging evidence that gastric electrical abnormalities contribute to this conduit dysfunction. A non-invasive medical device for body surface gastric mapping (BSGM) was recently developed to evaluate gastric electrical activity and function. This study aims to assess the feasibility of the novel BSGM device in the post-oesophagectomy stomach.

Methods
Patients who had undergone an esophagectomy at Auckland City Hospital (Auckland, New Zealand) between 2017-2022 were recruited following ethics approval. Exclusions comprised of patients undergoing adjuvant therapy or mechanical obstructions. The Gastric Alimetry System® (Auckland, New Zealand) was employed, comprising a stretchable array (8x8 electrodes; 196cm²) and cloud-based analytics platform. Following an overnight fast, 30 minutes of baseline recording was performed, followed by a meal challenge and 4 hours of post-prandial recordings. Symptoms were logged on a validated App. Spectral analysis of BSGM data was performed, with quantitative analysis including gastric frequency, BMI-adjusted amplitude, Gastric Alimetry Rhythm Index (a measure of rhythm stability) and meal response, compared to reference intervals in 110 healthy volunteers. Adverse events were also recorded.

Results
6 patients were recruited, including one who subsequently had a total gastrectomy and colonic interposition. Array placement was based on post-operative cross-sectional imaging. Only one patient was symptomatic during the session, with nausea, pain and early satiation. Gastric activity was successfully captured in all patients except the patient who had the colonic interposition (negative control), having no discernible gastric activity. 4/5 patients with gastric conduits showed abnormalities on Gastric Alimetry: 3 with low amplitude activity (<22μV), 3 had low gastric frequency (<2.65 cycles/min), 2 had low Gastric Alimetry Rhythm Index associated with unstable pacemaking. There were no adverse events.

Conclusion
Gastric Alimetry is a safe and feasible technique to non-invasively assess the gastric myoelectrical activity and motility following esophagectomy, identifying changes in gastric function. The significance for the management of post-oesophagectomy gastric dysfunction can now be evaluated.

<b>Figure 1</b> A. Patient who developed mild symptoms with normal gastric slow wave activity. B. Patient who developed sensorimotor symptoms after the meal challenge with abnormal gastric rhythm stability, low frequency, low BMI-adjusted amplitude and low meal response amplitude ratio.

Figure 1 A. Patient who developed mild symptoms with normal gastric slow wave activity. B. Patient who developed sensorimotor symptoms after the meal challenge with abnormal gastric rhythm stability, low frequency, low BMI-adjusted amplitude and low meal response amplitude ratio.

Introduction: One of the most debated issues in the practice of sleeve gastrectomy (SG) is the size of the bougie used during procedures. While larger size (50-Fr to 60-Fr) bougies initially used in SG are generally avoided these days, it has been suggested that the optimal size should be well below 40-Fr. The aim of this study was to compare the outcomes of choosing smaller versus larger bougies.

Methods: Literature search was done according to the PRISMA guidelines. 11 Observational cohort studies were included in the analysis. Meta-analysis was done using the RevMen 5.4.1 software. Statistical method used was Mantel-Haenszel. Analysis model used was random effects regardless of the heterogeneity (I²). The 11 studies compared different sets of sizes which is a limitation for this study. This study doesn’t compare between specific sizes but compare between outcomes of choosing smaller versus larger bougies regardless of the exact sizes.

Results: Significant difference in favor of smaller bougies was observed in ED visit due to dehydration (OR 0.92, CI 0.86, 0.98), and in excess weight loss % (EWL%) at 12 months (MD 5.92, CI 1.73, 10.11). However, significant difference in favor of larger bougies was observed in postoperative leaks (OR 1.20, CI 1.08, 1.33). No significant difference was observed in length of stay (MD -0.36, CI -1.24, 0.52), readmissions (OR 0.96, CI 0.72, 1.28), reoperations (OR 0.98, CI 0.55, 1.72), luminal complications (stenosis, strictures, kinks, obstructions) (OR 0.91, CI 0.04, 11.89), surgical site occurrences (infection, abscess, hematoma) (OR 1.36, CI 0.41, 4.48), or total complications (OR 1.74, CI 0.78, 3.9).

Conclusion: Smaller bougies decrease ED visit due to dehydration and increase EWL% at 12 months. However, they increase the risk of leaks. Further studies are warrented.

Purpose: Recently, bariatric and foregut surgery have become distinct entities under the minimally invasive surgery specialty, which has led some surgeons to subspecialize and focus solely on one or the other. There is currently a paucity of data to suggest this may lead to improved outcomes; therefore, the purpose of this study is to evaluate the outcomes of patients undergoing bariatric surgery and concurrent paraesophageal hernia repair (PEHR) by the same surgeon or by separate surgeons.
Materials and Methods: The 2015-2020 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) Registry was used to evaluate patients undergoing laparoscopic sleeve gastrectomy (LSG) or Roux-en-y gastric bypass (RNYGB) and PEHR done by the same or by separate surgeons. Outcomes were evaluated using descriptive statistics and multivariable regression.
Results: A total of 142,799 patients underwent LSG or RNYGB with concurrent PEHR, 139,742 (98%) by the same surgeon and 2,767 (2%) done by separate surgeons. Patients with PEHR done by separate surgeons were younger 44.8y vs 46.8y, with a lower BMI 42.4kg/m²vs 43.4, greater proportion of males 485(17.5%) vs 21,972(15.6%) and white patients 2442(88.3%) vs 102,751(73.1%). Univariate analysis demonstrated reduced complications in patients undergoing PEHR by separate surgeon in both SG and RNYGB, albeit increased readmissions in those undergoing RNYGB Table 1. On multivariable regression, PEHR by a separate surgeon was independently associated with fewer reinterventions (OR 0.53, C.I. 0.31-0.90, p=0.019), reduced case duration (RC -4.216, p<0.001), and shorter length of stay (RC -0.174, p<0.001). While more readmissions were noted in the RNYGB group with PEHR performed by a separate surgeon, this was not significant on multivariable analysis.
Conclusion: In this national database study, concomitant bariatric surgery and PEHR by separate surgeons was associated with reduced operating time, shorter length of stay, and fewer reinterventions. While this study suggests a benefit with collaboration between bariatric surgeons and foregut surgeons; additional studies are needed to further evaluate the indication and specialty of the separate surgeon to refine the observed results.

30 Day Complication in Bariatric Surgery Patients Undergoing Concomitant PEHR by the Same or Separate Surgeon

30 Day Complication in Bariatric Surgery Patients Undergoing Concomitant PEHR by the Same or Separate Surgeon

Introduction: Sleeve gastrectomy (SG) improves obesity and Type 2 diabetes (T2D). The added therapeutic potential of post-operative dietary interventions on obesity and T2D are understudied. Following SG, patients increase dietary protein consumption, however, protein restriction induces weight loss, improves metabolic health, and extends lifespan in mice and humans. We hypothesized reducing dietary protein intake following SG would improve post-operative weight loss, glucose tolerance, and metabolism.
Methods: Sixty-four, C57BL/6J mice were preconditioned on high-fat, western diet (WD) starting at 5 weeks of age. At 17 weeks, mice were weight-matched and received SG or sham surgery. After recovery, mice were placed into 1 of 4 dietary groups: High (36%), medium (21%), low protein (7%), or WD. All protein diets were isocaloric. A separate control group of 16 mice were preconditioned on normal chow diet (NCD; 5% fat, 24% protein), received SG or sham, and were maintained on NCD. Weights and food intake were tracked longitudinally. Glucose tolerance and insulin sensitivity were assessed via oral glucose and insulin tolerance testing, respectively. Body composition was determined through MRI spectroscopy. Energy expenditure (EE) was quantified using indirect calorimetry and normalized to lean mass. Grip strength was assessed using an inverted cling assay. Area under the curve analysis, one-way ANOVA with Dunnett corrections, and t-tests were used.
Results: SG induced weight loss across all groups compared to their respective Shams. SG mice on 7% protein had higher percent weight loss compared to other SG groups (Figure 1A) despite having increased daily food intake compared to SG mice on 36% protein (p=0.02) or WD (p=0.01). SG mice on 36% protein and NCD had the lowest fat mass (Figure 1B) and 36% SG mice had significantly elevated lean mass (Figure 1C) compared to other SG groups. Notably, 7% SG mice had equivalent lean mass to NCD and 21% SG groups. All SG mice had improved glucose tolerance compared to their respective shams (Figure 1D). 7% SG mice trended toward improved glucose tolerance and had significantly reduced fasting glucose compared to all SG groups (Figure 1E). This occurred independent of changes in insulin sensitivity, which was similar across all groups (Figure 1F). EE was increased in all mice consuming 36% compared to 7% protein in light and dark cycles. EE did not differ between sham and SG mice within the same diet group. Cling time did not differ between sham and SG mice in any diet group or when comparing 36% and 7% SG mice.
Conclusions: Protein restriction enhances weight loss and improves T2D control after SG. This occurs independent of changes in insulin sensitivity and has minimal effects on overall lean mass or grip strength. Controlling protein consumption may improve metabolic health outcomes for patients following SG.

Introduction:
In the United States, recreational and medicinal cannabis use has continually increased in recent years, including in patients undergoing bariatric surgery. However, the effects of cannabis use on morbidity and mortality after bariatric surgery are uncertain, and the current literature is limited by a paucity of studies. The purpose of this study is to evaluate the effects of cannabis use disorder on medical complications, in-hospital mortality, and length of stay (LOS) in a nationally representative cohort of patients undergoing bariatric surgery.
Methods:
The Nationwide Inpatient Sample 2016 - 2019 was queried for all patients ≥18 years who underwent roux-en-y gastric bypass (RYGB), vertical sleeve gastrectomy (VSG), or adjustable gastric band (AGB) surgery. Severe cannabis use was defined using ICD-10 coding for cannabis use disorder. Three outcomes were evaluated: medical complications, in-hospital mortality, and length of stay. Complications were defined as experiencing ≥1 myocardial infarction, cardiac arrest, venous thromboembolism (VTE), pulmonary embolism (PE), respiratory arrest, pneumonia, sepsis, stroke, and/or urinary/renal complication. Logistic regressions were used to evaluate effects of cannabis use disorder on medical complications and in-hospital mortality. Linear regression was used to determine an association with length of stay. All models controlled for race, age, sex, income, procedure type, and various medical comorbidities (hypertension, history of cancer, diabetes, and respiratory conditions).
Results:
A total of 713,290 patients were included in this study, with 1,870 (0.26%) having documented cannabis use disorder. Cannabis use disorder was significantly associated with the likelihood of experiencing a medical complication (OR: 2.24; 95% CI: 1.31 - 3.82; P=0.003) and longer lengths of stay (β: 1.3; SE: 0.297; P<0.001), but not in-hospital mortality (OR: 3.29; CI: 0.94 - 11.5); P=0.062).
Conclusions:
Severe cannabis use was associated with a higher risk for complications and extended length of stay. Future investigations are needed to better elucidate the relationship between cannabis use and bariatric surgery, including effects of dosage, chronicity, and method of ingestion.

Telemedicine has grown exponentially in health assistance. However, the safety and efficacy of this technology, and specifically the robot assisted telepresence (RAT), is still under scrutiny. We aimed to compare the use of RAT in surgical ward rounds versus traditional in-person rounds, to evaluate and discharge patients admitted after metabolic and bariatric surgery (MBS).
Methods:
We conducted a prospective, open-label, non-inferiority randomized controlled trial to investigate if the use of RAT during ward rounds and hospital discharge is non-inferior to in-person hospital ward round and hospital discharge, in patients admitted after MBS. All patients undergoing MBS were consecutively randomized, at the first postoperative day, and the discharge was planned to occur on the second day. Patients were seen during ward rounds by the multidisciplinary team (nurse, dietitian, physical therapist) physically present. The surgeon was either physically present (in-person) or remotely present via RAT. Telepresence robot used was a PadBot U2 (iPresence ltd., Japan) through a secure wi-fi connection. The primary endpoint was the rate of successful hospital discharges by the randomized method on the second postoperative day. Secondary endpoints included number of visits to the emergency department, hospital readmission, and patients’ perceptions evaluated by a validated questionnaire utilizing a Likert’ scaled evaluating 4 domains (communication, dignity and confidentiality, content, and timing).
Results:
Ninety-six patients meeting the inclusion criteria, who underwent laparoscopic MBS between February 2020 and May 2022, were randomly assigned to receive their discharge performed by a surgeon on RAT (n = 48) or in-person (n = 48). Table 1 shows clinical and demographic data from the study population. Hospital discharge assisted by a telepresence robot had no inferior rate of success than in-person (100% vs 100%, p < 0.001). There were no differences in number of patients seen in emergency (2.1% vs 2.1% p = 0.99), no readmission or reoperation were observed. The median score of the 4 questionnaires were similar in both groups for all domains evaluated communication [in-person: 5 (5-10) vs. RAT: 5 (5-10), P=0.75]; dignity and confidentiality [in-person: 2 (2-4) vs. RAT: 2 (2-4), P=0.99]; content [in-person: 5 (5-10) vs. RAT: 5 (5-10), P=0.8]; timing [in-person: 1 (1-2) vs. RAT: 1 (1-2), P=0.99].
Conclusions:
The use of RAT in ward rounds to discharge patients after MBS is non-inferior to the in-person visit. Additionally, the patients’ perception of communication, dignity and confidentiality, content, and timing was similar between groups. The use of telepresence in ward rounds might help the surgeon in patient management.

Introduction:
Bariatric surgery is widely performed to manage clinically severe obesity and its associated medical conditions. Though generally safe, complications can be difficult to manage, and rarely, catastrophic. Hospital characteristics may affect outcomes in bariatric surgery patients. The present study intends to evaluate effects of geographic region, hospital teaching status, and number of beds on outcomes after bariatric surgery using data sourced from the Nationwide Inpatient Sample (NIS) 2016 - 2019.
Methods:
Patients undergoing Roux-en-Y gastric bypass (RYGB), vertical sleeve gastrectomy (VSG), or adjustable gastric band (AGB) surgery were identified with ICD-10 coding. Hospitals were grouped by location/teaching status as “urban non-teaching,” “urban teaching,” and “rural.” Hospitals were trichotomized as low-volume, medium-volume, and high-volume. Geographic regions were Northeast, Midwest, South, and West. Outcomes were medical complications (≥1 myocardial infarction, cardiac arrest, venous thromboembolism, pulmonary embolism, respiratory arrest, pneumonia, sepsis, stroke, or urinary/renal complications), in-hospital mortality, and length of stay (LOS). Multivariate logistic regressions evaluated effects on medical complications and mortality, and generalized linear modeling was used for LOS. All models controlled for race, age, sex, household income, insurance, hypertension comorbidity, hospital teaching status, and hospital case volume.
Results:
A total of 713,290 patients were included (average age: 45.0 years, 79.2% female). Patients in high-volume hospitals were more likely to experience a medical complication than those in low-volume hospitals (OR: 1.23; 95% CI: 1.07 - 1.42). Patients treated in the Midwest (OR: 1.29; CI: 1.09 - 1.52) and South (OR: 1.27; CI: 1.07 - 1.51) were more likely to have a medical complication than those in the Northeast. Hospital location/teaching status did not have an effect. There was no effect of geographic region, hospital location/teaching status, and case volume on mortality. Medium-volume (β: 0.12; SE: 0.034; P<0.001) and high-volume (β: 0.38; SE: 0.065; P<0.001) had longer LOS. Hospitals in the Midwest (β: 0.08; SE: 0.038; P=0.033) and West (β: 0.11; SE: 0.040; P=0.006) had longer LOS. There was no effect of hospital location/teaching status.
Conclusions:
Patients treated in high-volume hospitals and in the Midwest were more likely to have a medical complication and longer LOS. However, it is important to note the relatively small effect sizes in this study. Future studies should use national data to better understand and address potential disparities in medical treatment based on hospital characteristics.

Shiv Patel

Appearances