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Background: Many surgical adverse events, such as bile duct injuries during laparoscopic cholecystectomy (LC), occur due to errors in visual perception and judgment. Artificial intelligence (AI) can potentially improve the quality and safety of surgery, such as through real-time intraoperative decision support. GoNoGoNet is a novel AI model capable of identifying safe ("Go") and dangerous ("No-Go") zones of dissection on surgical videos of LC. Yet, it is unknown how GoNoGoNet performs in comparison to expert surgeons. This study aims to evaluate the GoNoGoNet's ability to identify Go and No-Go zones compared to an external panel of expert surgeons., Methods: A panel of high-volume surgeons from the SAGES Safe Cholecystectomy Task Force was recruited to draw free-hand annotations on frames of prospectively collected videos of LC to identify the Go and No-Go zones. Expert consensus on the location of Go and No-Go zones was established using Visual Concordance Test pixel agreement. Identification of Go and No-Go zones by GoNoGoNet was compared to expert-derived consensus using mean F1 Dice Score, and pixel accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV)., Results: A total of 47 frames from 25 LC videos, procured from 3 countries and 9 surgeons, were annotated simultaneously by an expert panel of 6 surgeons and GoNoGoNet. Mean (± standard deviation) F1 Dice score were 0.58 (0.22) and 0.80 (0.12) for Go and No-Go zones, respectively. Mean (± standard deviation) accuracy, sensitivity, specificity, PPV and NPV for the Go zones were 0.92 (0.05), 0.52 (0.24), 0.97 (0.03), 0.70 (0.21), and 0.94 (0.04) respectively. For No-Go zones, these metrics were 0.92 (0.05), 0.80 (0.17), 0.95 (0.04), 0.84 (0.13) and 0.95 (0.05), respectively., Conclusions: AI can be used to identify safe and dangerous zones of dissection within the surgical field, with high specificity/PPV for Go zones and high sensitivity/NPV for No-Go zones. Overall, model prediction was better for No-Go zones compared to Go zones. This technology may eventually be used to provide real-time guidance and minimize the risk of adverse events., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objective: Due to the COVID-19 pandemic, the Coalition for Physician Accountability's work group on Medical Students in the class of 2021 made the recommendation in May of 2020 that the upcoming residency recruitment cycle be conducted virtually. This flexibility may have allowed applicants to apply and interview at programs with less regard to geography, knowing that travel costs of interviewing would not be a factor. Alternatively, applicants who interviewed virtually could choose to remain in a close proximity to their home institutions where they likely have a greater comfort level and familiarity with the community both personally and professionally. We examine the distribution of applicants matched at general surgery residency programs in 2021 to those in 2020 to see if there was a change in geographic variability., Design: Retrospective review of general surgery residents SETTING: United States general surgery residency programs PARTICIPANTS: 2153 PGY1 categorical general surgery residents who were interviewed virtually and PGY2 categorical general surgery residents who interviewed in-person, who also attended residency programs and medical schools located in the continental United States with publicly accessible residency websites containing necessary biographical information., Results: A total of 2153 residents were included; 1124 in their PGY1 and 1029 in their PGY2. Average distance from attended medical school to matched program (634.2 vs 662.5), percentage of matched programs within 500 miles of attended medical school (57.3 vs 55.7), average price of flight, when available, from attended medical school to matched program (222.8 vs 230.4), and percentage of attended medical schools with non-stop flight to matched program (42.9 vs 42.9) did not significantly differ between PGY1 and PGY2 residents., Conclusions: The decision to adopt virtual interviewing practices compared to previous in-person interviews did not significantly alter the geographical distribution of students' matched programs. The distance from medical school to the matched program, flight availability, and flight pricing remained comparable between residents interviewed in-person and residents interviewed virtually., (Copyright © 2022 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)

Background: National data show a trend favoring laparoscopic sleeve gastrectomy (SG) over Roux-en-Y gastric bypass (RYGB). Published data demonstrating the differences in weight loss between the two procedures are mixed., Objective: In this retrospective study using clinical data from 2010 to 2020, we compared the clinical and demographic characteristics of patients undergoing either SG or RYGB to evaluate their long-term weight loss outcomes., Setting: University hospital in the United States., Methods: A total of 3329 patients were identified in our institutional Metabolic and Bariatric Surgery Accreditation and Quality Improvement database using Current Procedural Terminology codes for either RYGB or SG. A general linear model was used for baseline characteristics. Logistic regression was used for factors favoring RYGB versus SG. A multivariable linear mixed model was used for weight-trajectory analysis. Cox regression was used for a cumulative hazard ratio of 10% weight regained from nadir., Results: Factors favoring RYGB were diagnoses of type 2 diabetes and gastroesophageal reflux disease, Hispanic ethnicity, and surgeon's preference. SG was favored among Black patients and smokers. RYGB was associated with more weight loss at all time points. The risk of weight regain was significantly higher after SG versus RYGB., Conclusions: The bariatric procedure choice is significantly influenced by race, medical history, and surgeon's experience. RYGB results in a significantly more durable weight loss compared with SG regardless of race or other stratification factors., (Copyright © 2022 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Gastrostomy placement is the preferred means of long-term enteral feeding for patients who cannot eat by mouth. During laparoscopic gastrostomy, it is standard to perform gastropexy, apposing visceral and parietal peritoneum. In some settings, due to altered anatomy from prior surgery, direct apposition of the stomach to the abdominal wall is not possible. This study reports a series of cases where laparoscopic gastrostomy was performed via a Witzel approach without gastropexy., Methods: A retrospective chart review was performed of all patients at a tertiary academic medical center who underwent Witzel gastrostomy without gastropexy over a 3-year period. In each case, an 18-French tube was placed into the fundus of the stomach and secured with a purse-string suture. A 5-cm serosalized Witzel tunnel was created around the tube using running silk suture. No gastropexy was performed., Results: Six patients underwent 7 Witzel gastrostomy procedures. In three cases, patients had undergone prior major upper abdominal surgery where adhesive disease prevented gastropexy. In the other four cases, the patients had undergone prior gastric bypass with antecolic antegastric position of the roux limb. No patient suffered leak of gastric contents into the peritoneum, and there were no postoperative complications or mortality related to the gastrostomy., Conclusion: In cases where enteral access is necessary, and where the stomach cannot reach the anterior abdominal wall for gastropexy due to prior surgeries, a Witzel gastrostomy without gastropexy is a safe option which resulted in no morbidity or mortality in our series.

Background: Medical student education is challenging, and concept maps (CMs) can help students link new and existing knowledge, promote critical thinking and identify knowledge gaps., Aims: To study the feasibility, acceptability, and effectiveness of CMs in problem-based learning (PBL) tutorials., Method: Students and tutors were randomized to tutorials that used or did not use CMs. A mixed-methods approach generated qualitative and quantitative results of participants' perspectives on and the effects of CMs in PBL tutorials., Results: Student survey response rate was 71% (122/172). Most students (82.6%) planned to use CMs in the future at least occasionally, and students in CM tutorials endorsed increased likelihood of using CMs in the future (p = 0.02) versus students in non-CM tutorials. Qualitative analyses identified consistent associations between CMs and recurrent themes: integration of physiological mechanisms, challenging students' knowledge of the material, and identification of knowledge gaps. Quantitative assessment of final exam scores revealed a statistically significant increase in the students' scores in CM tutorials versus students in non-CM tutorials with an a priori α of <0.10., Conclusions: CMs are well accepted by students and faculty, feasible to incorporate into PBL tutorials, and may result in improved exam performance and student learning of physiologic concepts.

Barrington's nucleus impacts on bladder and distal colon function and relays pelvic visceral information to the forebrain. This study investigated processing of information from the bladder and the distal colon by Barrington's nucleus in the rat. The responses of individual Barrington's nucleus neurons to bladder and/or colon distention were characterized using extracellular recording and the recorded neurons were identified using juxtacellular labelling. Most neurons within Barrington's nucleus (79%) were activated by bladder distention, consistent with its role as a pontine micturition centre. Although no neurons were selectively responsive to colon distention, the majority of bladder-responsive neurons (73%) were also activated by colon distention. In a second study, Barrington's nucleus neurons were characterized with respect to their response to colon distention and their immunoreactivity for the stress-related neuropeptide corticotropin-releasing factor (CRF). Of 30 labelled neurons in the central part of Barrington's nucleus, 53% were activated by colon distention and 63% of these were CRF-ir. This is the first report demonstrating that Barrington's nucleus neurons are responsive to colon distention. The results provide evidence for convergence of information from the bladder and the colon onto individual Barrington's nucleus neurons. Taken with evidence that many Barrington's nucleus neurons are synaptically linked to the bladder and colon, the present study suggests a role for these neurons in coordinating peripheral parasympathetic and central responses to both viscera and implicate CRF as a neurotransmitter in this function. Dysfunctions in this circuit may underlie the coexistence of colon and bladder symptoms observed in functional bowel disorders.

Basic and clinical studies suggest that neurokinin 1 (NK1) receptor antagonists have efficacy in the treatment of affective disorders through effects on the dorsal raphe nucleus (DR), a source of forebrain-projecting serotonin (5-HT) neurons that has also been implicated in affective disorders. To investigate the regulation of the DR-5-HT system by NK1 receptors, the effects of substance P (an NK1 agonist) on rat DR neuronal activity were characterized. Most of the DR neurons (83%; n = 47 total) were inhibited by substance P microinfusion into the DR, and in some cases (17%) this was preceded by a brief activation. Pure excitation was observed in a small population of neurons (17%) that were localized in the dorsal DR, where NK1 receptors are most dense. Sendide, a selective NK1 antagonist, attenuated the effects of substance P, indicating that they were mediated by NK1 receptor activation. The selective 5-HT1A antagonist, WAY 100635, administered systemically or into the DR, prevented the inhibitory effects of substance P, implicating DR 5-HT1A receptors in this response. Finally, microinfusion of the excitatory amino acid antagonist, kynurenic acid, into the DR prevented both excitatory and inhibitory effects. The results suggest that NK1 receptor activation in the DR excites a population of 5-HT neurons via glutamatergic transmission. This results in 5-HT release throughout the DR, activation of 5-HT1A receptors, and subsequent inhibition. Interactions between NK1 and 5-HT1A receptors within DR neural networks may contribute to the mechanism of action of novel antidepressants acting at NK1 receptors.

Corticotropin-releasing factor (CRF) has substantial effects on brain serotonergic activity, especially in limbic structures related to stress and anxiety. For example, relatively low doses of CRF administered into the dorsal raphe nucleus (DRN) decrease DRN unit activity and serotonin release in the lateral septum (LS), a limbic target of the DRN. In contrast, higher doses of CRF tend to be excitatory on both endpoints. The present experiment sought to establish the functional connection between CRF effects in the DRN and the ultimate effect on activity in the LS as a terminal region. We recorded the effects of CRF (3, 10, 30 and 100 ng in 100 nl of artificial cerebrospinal fluid) administered into the DRN upon LS unit activity. In general, the lower doses of CRF (3 and 10 ng) had a facilitatory effect on LS unit activity, peaking at about 15-20 min post-injection. The higher doses had a more complex effect with an early suppression of unit responding maximizing at about 5 min followed by a facilitatory rebound, especially at the 100 ng dose, maximizing at about 20 min. Taken with previous studies demonstrating an inhibitory effect of 5-HT on neuronal activity in LS, the findings suggest that CRF regulation of the DRN is translated to changes in LS activity. This effect may underlie certain coping behaviors in response to stress.