Secondary peristalsis and esophagogastric junction distensibility in symptomatic post-fundoplication patients.

BACKGROUND: The impact of esophageal dysmotility among patients with post-fundoplication esophageal symptoms is not fully understood. This study aimed to investigate secondary peristalsis and esophagogastric junction (EGJ) opening biomechanics using functional lumen imaging probe (FLIP) panometry in symptomatic post-fundoplication patients. METHODS: Eighty-seven adult patients post-fundoplication who completed FLIP for symptomatic esophageal evaluation were included. Secondary peristaltic contractile response (CR) patterns and EGJ opening metrics (EGJ distensibility index (EGJ-DI) and maximum EGJ diameter) were evaluated on FLIP panometry and analyzed against high-resolution manometry (HRM), patient-reported outcomes, and fundoplication condition seen on esophagram and/or endoscopy. KEY RESULTS: FLIP CR patterns included 14 (16%) normal CR, 30 (34%) borderline CR, 28 (32%) impaired/disordered CR, 13 (15%) absent CR, and 2 (2%) spastic reactive CR. Compared with normal and borderline CRs (i.e., CR patterns with distinct, antegrade peristalsis), patients with impaired/disordered and absent CRs demonstrated significantly greater time since fundoplication (2.4 (0.6-6.8) vs. 8.9 (2.6-14.5) years; p = 0.002), greater esophageal body width on esophagram (n = 50; 2.3 (2.0-2.8) vs. 2.9 (2.4-3.6) cm; p = 0.013), and lower EGJ-DI (4.3 (2.7-5.4) vs. 2.6 (1.7-3.7) mm2/mmHg; p = 0.001). Intact fundoplications had significantly higher rates of normal CRs compared to anatomically abnormal (i.e., tight, disrupted, slipped, herniated) fundoplications (9 (28%) vs. 5 (9%); p = 0.032), but there were no differences in EGJ-DI or EGJ maximum diameter. CONCLUSIONS & INFERENCES: Symptomatic post-fundoplication patients were characterized by frequent abnormal secondary peristalsis after fundoplication, potentially worsening with time after fundoplication or related to EGJ outflow resistance.

Increased bleeding risk with enoxaparin venothromboembolism prophylaxis compared with heparin in patients undergoing bariatric surgery.

BACKGROUND: Perioperative venothromboembolism (VTE) chemoprophylaxis is an established tenant of bariatric surgery; however, there is little comparative data to guide medication choice. The objective of this study was to determine if a change in VTE prophylaxis from heparin to enoxaparin was associated with differing rates of postoperative bleeding and VTE occurrence after bariatric surgery. METHODS: This retrospective cohort study included patients 18 years or older who underwent primary bariatric surgery (sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB)) at a single institution between March 2012 and December 2021. Subcutaneous unfractionated heparin was utilized for VTE prophylaxis from March 2012 through February 2018 and then enoxaparin was used from March 2018 through December 2021. Postoperative bleeding was defined as requiring a blood transfusion or reoperation for bleeding within 30 days of surgery. Chi-square test was used to test for differences between groups. RESULTS: There were 2159 patients who underwent bariatric surgery with 1324 (61.3%) patients in the heparin group and 835 (38.7%) in the enoxaparin group. Overall, 1,503 (69.6%) patients underwent SG and 656 (30.4%) RYGB. There was no difference in the ratio of SG to RYGB between the heparin and enoxaparin groups. Most patients were female (n = 1709, 79.2%) with a median age of 43.2 years (interquartile range (IQR): 35.6-52.2), and median BMI of 44.9 (IQR: 40.9-50.5). Overall postoperative bleeding occurred more frequently in the enoxaparin group (n = 26, 3.1%) compared with the heparin group (n = 12, 0.9%) (p < 0.01). Additionally, reoperation for bleeding was more frequent with enoxaparin (enoxaparin 0.8% vs. heparin 0.2%, p = 0.04). There was no difference in VTE occurrence between the two groups (heparin: n = 14, 1.1%, enoxaparin: n = 7, 0.8% (p = 0.61)). CONCLUSIONS: An institutional change from heparin to enoxaparin for bariatric surgery perioperative VTE prophylaxis was associated with a significant increase in postoperative bleeding, with no difference in VTE complications.

Preoperative Workup of Patients with Paraesophageal Hernias: Every Test for Every Patient?

Introduction: Paraesophageal hernias (PEH) represent a small subset of all hiatal hernias. PEHs are often found incidentally during radiographic or endoscopic studies performed for another reason. While asymptomatic or minimally symptomatic PEHs can be safely observed with nonoperative management, the majority of patients with symptomatic PEHs will benefit from surgical repair, typically via a laparoscopic approach. The decision to pursue surgical repair of PEHs is dependent on a thorough evaluation of the patient's symptoms as well as an appropriate workup of the relevant anatomy. This study aims to review components of the clinical workup of PEHs. Materials and Methods: A review of the contemporary literature addressing the issue of diagnostic workup of patients with PEHs was performed. Information from available studies were collected and organized into a brief review format. Results: Two key principles of the diagnostic evaluation of patients with PEHs include (1) establishing a link between patient symptoms and the PEH, and (2) identifying abnormal anatomy or physiology that may impact surgical repair (e.g., Barrett esophagus, esophageal stricture or diverticulum, delayed gastric emptying). While a multitude of radiographic, endoscopic, and functional testing options are available to evaluate PEH, selection of the appropriate test is dependent on patient clinical presentation. Conclusion: Successful management of PEHs depends on a thorough evaluation of patient symptoms and hernia anatomy. Therefore, patients with PEHs should undergo a history and physical examination, upper endoscopy, and obtain radiographic evaluation of the PEH (e.g., barium esophagram, computed tomography scan). Further testing should be directed by patient symptoms, especially in the case of discordance between symptoms and imaging findings.

Novel advances in surgery for Gallstone Disease.

PURPOSE OF REVIEW: Examine recent advances in the treatment of patients with complex gallstone disease. RECENT FINDINGS: Laparoscopic common bile duct exploration (LCBDE) has been shown to be an effective and safe treatment for choledocholithiasis, resulting in decreased hospital length of stay and costs when compared with ERCP plus laparoscopic cholecystectomy (LC). Novel simulator-based curricula have recently been developed to address the educational gap that has resulted in an underutilization of LCBDE. Patients with cholecystitis who are too ill to safely undergo LC have traditionally been treated with percutaneous cholecystostomy (PC). Endoscopic ultrasound (EUS) guided gallbladder drainage is a novel definitive treatment for such patients and has been shown to result in decreased complications and hospital readmissions compared to PC. The management of symptomatic gallstone disease during pregnancy has evolved over the last several decades. While it is now well established that laparoscopic procedures under general anesthesia are safe throughout a pregnancy, recent studies have suggested that laparoscopic cholecystectomy during the third trimester specifically may result in higher rates of preterm labor when compared with non-operative management. Finally, indocyanine green (ICG) fluorescence cholangiography is a novel imaging modality that has been used during laparoscopic cholecystectomy and may offer better visualization of biliary anatomy during dissection when compared with traditional intraoperative cholangiography. A number of recent technological, procedural, educational, and research innovations have enhanced and expanded treatment options for patients with complex gallstone disease.

Outcomes of 100 Patients More Than 4 Years After POEM for Achalasia.

OBJECTIVE: We aim to describe the long-term follow-up data from our institution's POEM experience. SUMMARY BACKGROUND DATA: Per-oral endoscopic myotomy (POEM) is a well-established endoscopic therapy for achalasia with excellent short-term efficacy, but long-term outcomes data are limited. METHODS: Patients older than 4 years removed from POEM for treatment of achalasia were studied. Clinical success was defined as an Eckardt Symptom (ES) score ≤3 and freedom from reintervention for achalasia. Patients underwent esophagogastroduodenoscopy (EGD), high-resolution manometry, impedance planimetry, and timed barium esophagram (TBE) preoperatively and at least 4 years postoperatively. Objective gastroesophageal reflux disease (GERD) was defined LA Grade B or worse esophagitis on EGD. RESULTS: One hundred and nineteen consecutive patients were included. Five patients died or had catastrophic events unrelated to achalasia or POEM. One hundred of the remaining patients (88%, 100/114) had long-term data available. Clinical follow-up for all patients was greater than 4 years postoperatively and the mean was 55 months. Mean current ES was significantly improved from preop (n = 100, 1 ±â€Š1 vs 7 ±â€Š2, P < 0.001). Overall clinical success was 88% and 92%. Five patients had a current ES >3 and 4 patients required procedural reintervention on the lower esophageal sphincter. Reinterventions were successful in 75% of patients (3/4), with current ES ≤3. The rate of objective GERD was 33% (15/45). Esophageal physiology was improved with a decrease in median integrated relaxation pressure (11 ±â€Š4 vs 33 ±â€Š15 mm Hg, P < 0.001), a decrease in median TBE column height (3 ±â€Š3 vs 13 ±â€Š8 cm, P < 0.001), and an increase in median distensibility index (5.1 ±â€Š2 vs 1.1 ±â€Š1 mm2/mm Hg, P < 0.001). CONCLUSIONS: POEM provides durable symptom relief and improvement in physiologic esophagogastric junction relaxation parameters over 4.5 years postoperatively. Reinterventions are rare and effective.

Comparison of preoperative, intraoperative, and follow-up functional luminal imaging probe measurements in patients undergoing myotomy for achalasia.

BACKGROUND AND AIMS: The functional luminal imaging probe (FLIP) is a novel catheter-based device that measures esophagogastric junction (EGJ) distensibility index (DI) in real time. Previous studies have demonstrated DI to be a predictor of post-treatment clinical outcomes in patients with achalasia. We sought to evaluate EGJ DI in patients with achalasia before, during, and after peroral endoscopic myotomy (POEM) and laparoscopic Heller myotomy (LHM) and to assess the correlation of DI with postoperative outcomes. METHODS: DI (defined as the minimum cross-sectional area at the EGJ divided by distensive pressure) was measured at 4 time points in patients undergoing surgical myotomy for achalasia: (1) during outpatient preoperative endoscopy (preoperative DI), (2) at the start of each operation after the induction of anesthesia (induction DI), (3) at the conclusion of each operation (postmyotomy DI), and (4) at routine follow-up endoscopy 12 months postoperatively (follow-up DI). Routine Eckardt symptom score, endoscopy, timed barium esophagram, and pH study were obtained 12 months postoperatively. RESULTS: Forty-six patients (35 POEM, 11 LHM) underwent FLIP measurements at all 4 time points. Preoperative and induction mean DI were similar for both groups (POEM, 1 vs .9 mm2/mm Hg; LHM, 1.7 vs 1.5 mm2/mm Hg). POEM resulted in a significant increase in DI (induction .9 vs postmyotomy 7 mm2/mm Hg, P < .001). There was a subsequent decrease in DI in the follow-up period (postmyotomy 7 vs follow-up 4.8 mm2/mm Hg, P < .01), but DI at follow-up was still significantly improved from preoperative values (P < .001). For LHM patients, DI also increased as a result of surgery (induction 1.5 vs postmyotomy 5.9 mm2/mm Hg, P < .001); however, the increase was smaller than in POEM patients (DI increase 4.4 vs 6.2 mm2/mm Hg, P < .05). After LHM, DI also decreased in the follow-up period, but this change was not statistically significant (5.9 vs 4.4 mm2/mm Hg, P = .29). LHM patients with erosive esophagitis on follow-up endoscopy had a significantly higher postmyotomy DI compared with those without esophagitis (9.3 vs 4.8 mm2/mm Hg, P < .05). CONCLUSIONS: EGJ DI improved dramatically as a result of both POEM and LHM, with POEM resulting in a larger increase. Mean DI decreased at intermediate follow-up but remained well above previously established thresholds for symptom recurrence. DI at the conclusion of LHM was predictive of erosive esophagitis in the postoperative period, which supports the potential use of FLIP for calibration of partial fundoplication construction during LHM.

Addressing the gap in laparoscopic common bile duct exploration training for rural surgeons: imparting procedural ability is not enough.

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) is an underutilized therapy for choledocholithiasis. The driving factors of this practice gap are poorly defined. We sought to evaluate the attitudes and practice patterns of surgeons who underwent training courses using an LCBDE simulator. METHODS: Surgeons completed a half-day simulator-based LCBDE curriculum at national courses, including the American College of Surgeons Advanced Skills Training for Rural Surgeons and the Society of American Gastrointestinal and Endoscopic Surgeons annual meeting. Attitudes were assessed with Likert surveys immediately before and after curriculum completion. Follow-up surveys were distributed electronically. RESULTS: 159 surgeons completed training during six courses. Surgeon attitudes regarding the overall superiority of LCBDE vs. ERCP shifted towards favoring LCBDE after course participation (4.0 vs 3.3; Likert scale 1-5, p < 0.001). 44% of surgeons completed follow-up surveys at a mean of 3 years post-course. Surgeons remained confident in their ability to perform LCBDE, with only 14% rating their skill as a significant barrier to practice, as compared with 43% prior to course participation (p < 0.01). However, only 28% of surgeons saw an increase in LCBDE volume. Deficiencies in operating room (OR) staff knowledge and instrument availability were the most significant barriers to post-course practice implementation and were inversely correlated with LCBDE case volume (ρ = - 0.44 and - 0.47, both p < 0.01). Surgeons for whom OR staff knowledge of LCBDE was not a significant barrier performed nearly 4 times more LCBDE than those who rated staff knowledge as a moderate, strong, or complete barrier. CONCLUSIONS: Surgeons trained at an LCBDE course retained long-term confidence in their procedural ability. Practice implementation was hindered by deficiencies in OR staff knowledge and instrument availability. Surgeons with knowledgeable operating room staff performed significantly more LCBDEs than those with less capable assistance. These barriers should be addressed in future curricula to improve procedural adoption.

Complications and Readmissions Associated with First Assistant Training Level Following Elective Bariatric Surgery.

BACKGROUND: Little is known regarding the variation in training level and potential clinical impact of the first assistant in bariatric surgery. We describe the postoperative 30-day complications and readmissions following elective bariatric procedures by training level of the first assistant. METHODS: The ACS-MBSAQIP database was queried to identify patients who underwent elective sleeve gastrectomy, Roux-En-Y gastric bypass, duodenal switch, band placement, and revision from 2015 to 2016. Patients were divided into cohorts based on training level of the first assistant (attending, fellow, resident, physician assistant/nurse practitioner, none). Outcomes included 30-day death or serious morbidity (DSM) and readmission. Multivariable logistic regression models, adjusting for patient and procedure characteristics, were estimated to examine differences in outcomes by first assistant training level. RESULTS: Of 410,535 procedures performed between 2015 and 2016, the training level of the first assistant included 21.3% attending, 8.7% fellow, 16.5% resident, 37.6% PA/NP, and 15.9% none. Operative time was significantly longer in the fellow and resident first assistant cohorts when compared with all other cohorts. Overall rates of 30-day DSM were low, ranging from 3.2 to 3.8%, while 30-day readmission rates ranged from 5.1 to 5.9%. Following adjustment for patient characteristics and type of procedure, first assistant training level had no significant impact on DSM or readmission. CONCLUSIONS: Variation in training level of the first assist during bariatric surgery had no influence on DSM or readmissions. This provides reassurance that the inclusion of a wide range of first assistants in bariatric procedures does not negatively impact patient outcomes.

Intraoperative use of FLIP is associated with clinical success following POEM for achalasia.

BACKGROUND: Esophagogastric junction distensibility index (DI), measured using the functional luminal imaging probe (FLIP), correlates with symptomatic outcomes after interventions for achalasia. The objective of this study was to determine if the intraoperative measurement of DI using FLIP was associated with improved clinical outcomes following per-oral endoscopic myotomy (POEM) for achalasia when compared with procedures in which FLIP was not utilized. METHODS: Patients undergoing POEM from 2012 to 2017 at a single institution by a single surgeon were studied. Use of FLIP during this time period was based on catheter and technician availability, resulting in two patient cohorts. In patients in whom FLIP was used, operative video recordings were reviewed to determine when DI measurements led to the performance of additional myotomy. Postoperative Eckardt symptom scores (ES) at 12 months and postoperative physiologic studies were compared between patients with and without intraoperative FLIP. Associations were assessed using Mann-Whitney U and Chi-square tests. RESULTS: 143 patients were included in the analysis (61 with intraoperative FLIP and 82 without FLIP). Video recordings were available for 85% of the FLIP cohort. Review of these operative recordings revealed that 65% of patients who underwent FLIP had additional myotomy performed following the initial postmyotomy FLIP measurement. At 12 months after POEM, the FLIP cohort had significantly more clinical successes (defined as ES ≤ 3) than patients in whom FLIP was not used (93% vs. 81%, p < 0.05). CONCLUSIONS: Use of intraoperative FLIP during POEM resulted in the surgeon performing additional myotomy in over half of cases and was associated with improved clinical outcomes. This study demonstrates the potential for a FLIP-tailored myotomy to improve outcomes in patients undergoing surgical myotomy for achalasia.

Intraoperative FLIP distensibility during POEM varies according to achalasia subtype.

BACKGROUND: The functional luminal imaging probe (FLIP) can be used to measure the esophagogastric junction distensibility index (DI) during myotomy for achalasia and increased DI has been shown to predict superior clinical outcomes. The objective of this study was to determine if the intraoperative DI and the changes produced by per oral endoscopic myotomy (POEM) differed between achalasia subtypes. METHODS: FLIP measurements were performed during POEM for achalasia at a single institution. DI (defined as the minimum cross-sectional area (CSA) at the EGJ divided by distensive pressure) was measured at three time points: after induction of anesthesia, after submucosal tunneling, and after myotomy. Measurements were reported at the 40 mL fill volume for the 8 cm FLIP (EF-325) and at the 60 mL fill volume for the 16 cm FLIP (EF-322). Measurements were compared using chi-square and Kruskal-Wallis tests. RESULTS: 142 patients had intraoperative FLIP performed during POEM for achalasia between 2012 and 2019 (30 type I, 68 type II, 27 type III, and 17 variant). Patients with type I achalasia had a significantly higher induction DI (median 1.7 mm2/mmHg) than type II (0.8 mm2/mmHg), type III (0.9 mm2/mmHg), and variants (1.1 mm2/mmHg; p < 0.001). These differences persisted after submucosal tunneling and final DI after myotomy was also significantly higher in type I patients (median 8.0 mm2/mmHg) compared to type II (5.8 mm2/mmHg), type III (3.9 mm2/mmHg), and variants (5.4 mm2/mmHg; p < 0.001). Achalasia subtypes were found to have similar CSA at all time points, whereas pressure differed with type I having the lowest pressure and type III the highest. CONCLUSION: The DI at each operative step during POEM was found to differ significantly between achalasia subtypes. These differences in DI were due to pressure, as CSA was similar between subtypes. Achalasia subtype should be accounted for when using FLIP as an intraoperative calibration tool and in future studies examining the relationship between DI and clinical outcomes.

Achalasia subtypes can be identified with functional luminal imaging probe (FLIP) panometry using a supervised machine learning process.

BACKGROUND: Achalasia subtypes on high-resolution manometry (HRM) prognosticate treatment response and help direct management plan. We aimed to utilize parameters of distension-induced contractility and pressurization on functional luminal imaging probe (FLIP) panometry and machine learning to predict HRM achalasia subtypes. METHODS: One hundred eighty adult patients with treatment-naïve achalasia defined by HRM per Chicago Classification (40 type I, 99 type II, 41 type III achalasia) who underwent FLIP panometry were included: 140 patients were used as the training cohort and 40 patients as the test cohort. FLIP panometry studies performed with 16-cm FLIP assemblies were retrospectively analyzed to assess distensive pressure and distension-induced esophageal contractility. Correlation analysis, single tree, and random forest were adopted to develop classification trees to identify achalasia subtypes. KEY RESULTS: Intra-balloon pressure at 60 mL fill volume, and proportions of patients with absent contractile response, repetitive retrograde contractile pattern, occluding contractions, sustained occluding contractions (SOC), contraction-associated pressure changes >10 mm Hg all differed between HRM achalasia subtypes and were used to build the decision tree-based classification model. The model identified spastic (type III) vs non-spastic (types I and II) achalasia with 90% and 78% accuracy in the train and test cohorts, respectively. Achalasia subtypes I, II, and III were identified with 71% and 55% accuracy in the train and test cohorts, respectively. CONCLUSIONS AND INFERENCES: Using a supervised machine learning process, a preliminary model was developed that distinguished type III achalasia from non-spastic achalasia with FLIP panometry. Further refinement of the measurements and more experience (data) may improve its ability for clinically relevant application.

Constructing Learning Curves to Benchmark Operative Performance of General Surgery Residents Against a National Cohort of Peers.

OBJECTIVE: No method or data exist to allow surgical trainees or their programs to contextualize their technical progress. The objective of this study was to create peer benchmarks for Cumulative Sum (CUSUM) charts based upon operative evaluations from a national cohort of general surgery residents. DESIGN, SETTING, PARTICIPANTS: In 2016-2018, faculty from 26 general surgery residency programs nationwide rated 328 residents' operative performance on a case-by-case basis using a validated 5-point Likert scale. An individual case was considered a "misstep" if scoring below the national median score for that procedure in that postgraduate year (PGY). We constructed 2-sided observed-expected CUSUM charts to capture each resident's cumulative performance over time relative to the national medians. Upper (failure) and lower (positive outlier) benchmarks were established based on the PGY-specific 75th percentile and median misstep rates; consistent/repeated missteps are reflected by crossing of the upper boundary. Procedures with ≤10 observations and residents who were evaluated <10 times for each PGY were excluded. RESULTS: Around 8,161 evaluations on 76 procedure types were analyzed. The individual misstep rate was lowest among PGY-3s at 13.3% and highest among PGY-4s at 28.6%. No interns had curves that crossed the failure boundary. 8.7% of PGY-2s and 8.9% of PGY-3s finished the year past the failure boundary. PGY-2s had the most positive outliers, with 28.3% of them demonstrating an outlying success performance beyond the lower boundary for at least once. PGY-5s most frequently failed, with 16.7% ever crossing the upper boundary and 11.1% remaining above it at graduation. CONCLUSIONS: CUSUM is a valid statistical approach for benchmarking individual residents' operative performance against national peers as they progress through the year in real-time. With further validation, CUSUM could be used to set progression and/or graduation standards and objectively identify residents who might benefit from remediation.

Concordance Between Expert and Nonexpert Ratings of Condensed Video-Based Trainee Operative Performance Assessment.

OBJECTIVE: We examined the impact of video editing and rater expertise in surgical resident evaluation on operative performance ratings of surgical trainees. DESIGN: Randomized independent review of intraoperative video. SETTING: Operative video was captured at a single, tertiary hospital in Boston, MA. PARTICIPANTS: Six common general surgery procedures were video recorded of 6 attending-trainee dyads. Full-length and condensed versions (n = 12 videos) were then reviewed by 13 independent surgeon raters (5 evaluation experts, 8 nonexperts) using a crossed design. Trainee performance was rated using the Operative Performance Rating Scale, System for Improving and Measuring Procedural Learning (SIMPL) Performance scale, the Zwisch scale, and ten Cate scale. These ratings were then standardized before being compared using Bayesian mixed models with raters and videos treated as random effects. RESULTS: Editing had no effect on the Operative Performance Rating Scale Overall Performance (-0.10, p = 0.30), SIMPL Performance (0.13, p = 0.71), Zwisch (-0.12, p = 0.27), and ten Cate scale (-0.13, p = 0.29). Additionally, rater expertise (evaluation expert vs. nonexpert) had no effect on the same scales (-0.16 (p = 0.32), 0.18 (p = 0.74), 0.25 (p = 0.81), and 0.25 (p = 0.17). CONCLUSIONS: There is little difference in operative performance assessment scores when raters use condensed videos or when raters who are not experts in surgical resident evaluation are used. Future validation studies of operative performance assessment scales may be facilitated by using nonexpert surgeon raters viewing videos condensed using a standardized protocol.

Intraoperative assessment of esophageal motility using FLIP during myotomy for achalasia.

BACKGROUND: The functional luminal imaging probe (FLIP) can evaluate esophagogastric junction (EGJ) distensibility and esophageal peristalsis in real time. FLIP measurements performed during diagnostic endoscopy can accurately discriminate between healthy controls and patients with achalasia based on EGJ-distensibility and distinct motility patterns termed repetitive antegrade contractions (RACs) and repetitive retrograde contractions (RRCs). We sought to evaluate real-time motility changes in patients undergoing surgical myotomy for achalasia. METHODS: FLIP measurements using a stepwise volumetric distention protocol were performed at three time points during assessment and performance of laparoscopic Heller myotomy and POEM: (1) During preoperative outpatient endoscopy, (2) Intraoperatively following induction of anesthesia, and (3) Intraoperatively after myotomy completion. EGJ-distensibility, contractility, RACs, and RRCs were measured. RESULTS: FLIP measurements were performed in 32 patients. The EGJ-distensibility index was similar between the preoperative and initial operative measurements (1.1 vs 1.4 mm2/mmHg, p = NS). There was a significant increase in distensibility following surgical myotomy (1.4 to 4.7 mm2/mmHg, p < 0.01). Intraoperative contractile patterns varied between achalasia subtypes. Contractility was seen in < 20% of assessments in patients with types I and II achalasia. Type III patients demonstrated contractility in 100% of assessments, with 70% exhibiting RRCs and 60% RACs. There was a reduction in the frequency of RRC presence (70% to 20%), and contractile vigor (80% to 0% of patients with lumen occluding contractions) in type III patients following surgical myotomy. CONCLUSIONS: This first report of real-time intraoperative measurement of esophageal motility using FLIP demonstrates the feasibility of such assessments during surgical myotomy for achalasia. Patients with type I and II achalasia exhibited rare intraoperative contractility, while the presence of motility was the norm in those with type III. Patients with type III achalasia demonstrated an immediate reduction in repetitive contraction motility patterns and contractile vigor following myotomy.

Post-Operative Complications and Readmissions Associated with Smoking Following Bariatric Surgery.

BACKGROUND: The link between smoking and poor postoperative outcomes is well established. Despite this, current smokers are still offered bariatric surgery. We describe the risk of postoperative 30-day complications and readmission following laparoscopic sleeve gastrectomy and laparoscopic Roux-En-Y gastric bypass in smokers. METHODS: The National Surgical Quality Improvement Program database was queried to identify patients who underwent laparoscopic sleeve gastrectomy and Roux-En-Y gastric bypass from 2012 to 2017. Patient outcomes were compared based on smoking status. Primary outcomes included 30-day readmission and death or serious morbidity. Secondary outcomes included wound and respiratory complications. Multivariable logistic regression was used to determine the association between smoking status and measured outcomes. RESULTS: Of the 133,417 patients who underwent bariatric surgery, 12,424 (9.3%) were smokers. Smokers more frequently experienced readmission (4.9% v 4.1%, p < 0.001), death or serious morbidity (3.8% v 3.4%, p = 0.019), wound complications (2% v 1.4%, p < 0.001), and respiratory complications (0.8% v 0.5%, p < 0.001). The likelihood of death or serious morbidity (OR 1.13, 95% CI 1.01-1.26), readmission (OR 1.21, 95% CI 1.10-1.33), wound (OR 1.44, 95% CI 1.24-1.68), and respiratory complications (OR 1.69, 95% CI 1.34-2.14) were greater in smokers. The adjusted ORs remained significant on subgroup analysis of laparoscopic sleeve gastrectomy and Roux-En-Y gastric bypass patients, with the exception of death or serious morbidity in laparoscopic Roux-En-Y gastric bypass (OR 1.04, 95% CI 0.89-1.24). CONCLUSIONS: Smokers undergoing bariatric surgery experience significantly worse 30-day outcomes when compared with non-smokers. There should be a continued emphasis on perioperative smoking cessation for patients being evaluated for bariatric surgery.

Can Impedance-pH Testing on Medications Reliably Identify Patients with GERD as Defined by Pathologic Esophageal Acid Exposure off Medications?

INTRODUCTION: Impedance-pH testing (MII-pH) while patients are on acid suppression medications is frequently used to evaluate persistent reflux symptoms. The aim of this study was to determine whether MII-pH on medications can reliably identify patients with gastroesophageal reflux disease (GERD) as defined by pathologic esophageal acid exposure off medications, and to determine if there is a threshold of total reflux episodes on medications where pH testing off medications may be unnecessary. METHODS: A retrospective review identified all patients between 1/2010 and 4/2017 who underwent MII-pH testing on PPI medications and subsequently had pH testing off medications. GERD was defined on pH testing off medications by an abnormal DeMeester Score (DMS) and on MII-pH on medications by ≥ 48 total reflux episodes. Patients with an abnormal DMS by MII-pH on medications were excluded. RESULTS: There were 71 patients, (22 males; 49 females), with a median age of 52 years. Based on ≥ 48 total reflux episodes by MII-pH testing on medications, 42 patients (59%) had GERD. When tested off medications, an abnormal DMS was present in 44 patients (62%). Among those with GERD based on impedance testing on medications, 31% did not have GERD based on pH testing off medications. Further, in the 29 patients with ≤ 48 total reflux episodes on MII-pH (normal test), 15 patients (52%) had pathologic acid exposure off medications. When there were > 73 reflux events with MII-pH on medications, all 15 patients in our series had pathologic acid exposure on pH testing off medications. CONCLUSION: MII-pH testing on medications in patients with refractory GERD symptoms does not reliably correlate with a diagnosis of GERD as defined by pathologic esophageal acid exposure off medications. The commonly used abnormal MII-pH test value of ≥ 48 total reflux episodes is not validated and should not be used. However, in our series, patients with > 73 total reflux episodes had a high likelihood of having pathologic acid exposure off medications. Overall, the preferred strategy to evaluate patients with persistent GERD symptoms on acid suppression therapy should be pH testing off medications.

The Role of Novel Functional Probes in the Evaluation and Treatment of Esophageal Disease.

The understanding of esophageal function and dysfunction in a variety of disease states has been driven largely by the introduction of a variety of measurement technologies. Included in these are contrast esophagram, computed tomography, high-resolution manometry, and 24-hour pH monitoring. Two novel measurement technologies, the functional lumen imaging probe (FLIP) and mucosal impedance (MI) catheter have recently introduced and studied. This review will discuss the technological basis of these tools and the evidence behind their application in the measurement of esophageal anatomy, physiology, and histology pertaining to a number of diseases, including gastroesophageal reflux disease, achalasia, and esosinophilic esophagitis.

Submucosal surgery: novel interventions in the third space.

Traditional surgeries involve accessing body cavities, such as the abdomen and thorax, via incisions that divide skin and muscle. These operations result in postoperative pain and convalescence, and a risk of complications such as wound infection and hernia. The development of flexible endoscopy allowed diseases as varied as gastrointestinal bleeding and colon adenomas to be treated without incisions, but this technique is restricted by its endoluminal nature. A novel category of surgical endoscopic procedures has recently been developed that uses flexible endoscopic techniques to enter and access the submucosa of the gastrointestinal tract. Through this approach, the advantages of incisionless endoscopy can be applied to areas of the body that previously could only be reached with surgery. This Review introduces this new class of interventions by describing two examples of such submucosal surgeries for the treatment of benign gastrointestinal disease: per-oral endoscopic myotomy and per-oral pyloromyotomy. The approach to pre-procedure patient evaluation, operative technique, and the published outcomes are discussed, as well as potential future applications of similar techniques and procedures in this so-called third space.

Effect of Ongoing Assessment of Resident Operative Autonomy on the Operating Room Environment.

OBJECTIVE: We have previously demonstrated the feasibility and validity of a smartphone-based system called Procedural Autonomy and Supervision System (PASS), which uses the Zwisch autonomy scale to facilitate assessment of the operative performances of surgical residents and promote progressive autonomy. To determine whether the use of PASS in a general surgery residency program is associated with any negative consequences, we tested the null hypothesis that PASS implementation at our institution would not negatively affect resident or faculty satisfaction in the operating room (OR) nor increase mean OR times for cases performed together by residents and faculty. METHODS: Mean OR times were obtained from the electronic medical record at Northwestern Memorial Hospital for the 20 procedures most commonly performed by faculty members with residents before and after PASS implementation. OR times were compared via two-sample t-test. The OR Educational Environment Measure tool was used to assess OR satisfaction with all clinically active general surgery residents (n = 31) and full-time general surgery faculty members (n = 27) before and after PASS implementation. Results were compared using the Mann-Whitney rank sum test. RESULTS: A significant prolongation in mean OR time between control and study period was found for only 1 of the 20 operative procedures performed at least 20 times by participating faculty members with residents. Based on the overall survey score, no significant differences were found between resident and faculty responses to the OR Educational Environment Measure survey before and after PASS implementation. When individual survey items were compared, while no differences were found with resident responses, differences were noted with faculty responses for 7 of the 35 items addressed although after Bonferroni correction none of these differences remained significant. CONCLUSIONS: Our data suggest that PASS does not increase mean OR times for the most commonly performed procedures. Resident OR satisfaction did not significantly change during PASS implementation, whereas some changes in faculty satisfaction were noted suggesting that PASS implementation may have had some negative effect with them. Although the effect on faculty satisfaction clearly requires further investigation, our findings support that use of an autonomy-based OR performance assessment system such as PASS does not appear to have a major negative influence on OR times nor OR satisfaction.

Impedance-pH monitoring on medications does not reliably confirm the presence of gastroesophageal reflux disease in patients referred for antireflux surgery.

INTRODUCTION: The gold standard for the objective diagnosis of gastroesophageal reflux disease (GERD) is ambulatory-pH monitoring off medications. Increasingly, impedance-pH (MII-pH) monitoring on medications is being used to evaluate refractory symptoms. The aim of this study was to determine whether an MII-pH test on medications can reliably detect the presence of GERD. METHODS: Patients referred for persistent reflux symptoms despite pH confirmed adequate acid suppression (DeMeester score ≤14.7) were reviewed retrospectively. All patients who originally had MII-pH testing on medications were re-evaluated with an off medication Bravo-pH study. Acid exposure results (defined by off medication Bravo) were compared to the original on medication MII-pH. RESULTS: There were 49 patients who met study criteria (median age 51). Patients had normal acid exposure during their MII-pH test on medications (average DMS 4.35). Impedance was abnormal (normal ≤47) in 25 of the 49 patients (51%). On subsequent Bravo-pH off medications, 37 patients (75.7%) showed increased esophageal acid exposure (average DMS 36.4). Bravo-pH testing was abnormal in 84% of patients with abnormal MII testing and in 67% with normal MII testing. The sensitivity and specificity of an abnormal MII-pH on medications for increased esophageal acid exposure off medications was 56.8 and 66.7%, respectively. The positive predictive value of confirming GERD from an abnormal MII-pH on medications is 84%, while the negative predictive value is 33.3%. A receiver operating characteristic (ROC) curve was generated and the area under the curve was 0.71, indicating that MII-pH on medications is a fair test (0.7-0.8) in diagnosing pathologic GERD. CONCLUSION: Compared to the gold standard, MII-pH on medications does not reliably confirm the presence of GERD. Excellent outcomes with antireflux surgery are dependent on the presence of GERD; thus, patients should not be offered antireflux surgery until GERD is confirmed with pH testing off medications.