Evaluation of 30-day outcomes for open ventral hernia repair using self-gripping versus nonself-gripping mesh.

BACKGROUND: The use of mesh is standard of care for large ventral hernias repaired on an elective basis. The most used type of mesh includes synthetic polypropylene mesh; however, there has been an increase in the usage of a new polyester self-gripping mesh, and there are limited data regarding its efficacy for ventral hernia. The purpose of the study is to determine whether there is a difference in surgical site occurrence (SSO), surgical site infection (SSI), surgical site occurrence requiring procedural intervention (SSOPI), and recurrence at 30 days after ventral hernia repair (VHR) using self-gripping (SGM) versus non-self-gripping mesh (NSGM). METHODS: We performed a retrospective study from January 2014 to April 2022 using the Abdominal Core Health Quality Collaborative (ACHQC). We collected data on patients over 18 years of age who underwent elective open VHR using SGM or NSGM and whom had 30-day follow-up. Propensity matching was utilized to control for variables including hernia width, body mass index, age, ASA, and mesh location. Data were analyzed to identify differences in SSO, SSI, SSOPI, and recurrence at 30 days. RESULTS: 9038 patients were identified. After propensity matching, 1766 patients were included in the study population. Patients with SGM had similar demographic and clinical characteristics compared to NSGM. The mean hernia width to mesh width ratio was 8 cm:18 cm with NSGM and 7 cm:15 cm with SGM (p = 0.63). There was no difference in 30-day rates of recurrence, SSI or SSO. The rate of SSOPI was also found to be 5.4% in the nonself-gripping group compared to 3.1% in the self-gripping mesh group (p < .005). There was no difference in patient-reported outcomes at 30 days. CONCLUSIONS: In patients undergoing ventral hernia repair with mesh, self-gripping mesh is a safe type of mesh to use. Use of self-gripping mesh may be associated with lower rates of SSOPI when compared to nonself-gripping mesh.

Application of machine learning to predict postoperative gastrointestinal bleed in bariatric surgery.

BACKGROUND: Postoperative gastrointestinal bleeding (GIB) is a rare but serious complication of bariatric surgery. The recent rise in extended venous thromboembolism regimens as well as outpatient bariatric surgery may increase the risk of postoperative GIB or lead to delay in diagnosis. This study seeks to use machine learning (ML) to create a model that predicts postoperative GIB to aid surgeon decision-making and improve patient counseling for postoperative bleeds. METHODS: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database was used to train and validate three types of ML methods: random forest (RF), gradient boosting (XGB), and deep neural networks (NN), and compare them with logistic regression (LR) regarding postoperative GIB. The dataset was split using fivefold cross-validation into training and validation sets, in an 80/20 ratio. The performance of the models was assessed using area under the receiver operating characteristic curve (AUROC) and compared with the DeLong test. Variables with the strongest effect were identified using Shapley additive explanations (SHAP). RESULTS: The study included 159,959 patients. Postoperative GIB was identified in 632 (0.4%) patients. The three ML methods, RF (AUROC 0.764), XGB (AUROC 0.746), and NN (AUROC 0.741) all outperformed LR (AUROC 0.709). The best ML method, RF, was able to predict postoperative GIB with a specificity and sensitivity of 70.0% and 75.4%, respectively. Using DeLong testing, the difference between RF and LR was determined to be significant with p < 0.01. Type of bariatric surgery, pre-op hematocrit, age, duration of procedure, and pre-op creatinine were the 5 most important features identified by ML retrospectively. CONCLUSIONS: We have developed a ML model that outperformed LR in predicting postoperative GIB. Using ML models for risk prediction can be a helpful tool for both surgeons and patients undergoing bariatric procedures but more interpretable models are needed.

Reconstruction of Scalp Wounds in Patients With Excoriation Disorder.

Excoriation or skin picking disorder is described as compulsive picking of the skin that cannot be explained by an underlying dermatological condition. There are unfortunately no clear guidelines in the literature for reconstruction of wounds in this patient population. The authors describe the cases of 2 patients with the skin picking disorder who underwent free flap reconstruction for scalp wounds, which were complicated by wound recurrence due to manipulation of the surgical site. The literature is reviewed in detail, and steps to potentially prevent recurrence in this patient population are discussed.

LF4/MOK and a CDK-related kinase regulate the number and length of cilia in Tetrahymena.

The length of cilia is controlled by a poorly understood mechanism that involves members of the conserved RCK kinase group, and among them, the LF4/MOK kinases. The multiciliated protist model, Tetrahymena, carries two types of cilia (oral and locomotory) and the length of the locomotory cilia is dependent on their position with the cell. In Tetrahymena, loss of an LF4/MOK ortholog, LF4A, lengthened the locomotory cilia, but also reduced their number. Without LF4A, cilia assembled faster and showed signs of increased intraflagellar transport (IFT). Consistently, overproduced LF4A shortened cilia and downregulated IFT. GFP-tagged LF4A, expressed in the native locus and imaged by total internal reflection microscopy, was enriched at the basal bodies and distributed along the shafts of cilia. Within cilia, most LF4A-GFP particles were immobile and a few either diffused or moved by IFT. We suggest that the distribution of LF4/MOK along the cilium delivers a uniform dose of inhibition to IFT trains that travel from the base to the tip. In a longer cilium, the IFT machinery may experience a higher cumulative dose of inhibition by LF4/MOK. Thus, LF4/MOK activity could be a readout of cilium length that helps to balance the rate of IFT-driven assembly with the rate of disassembly at steady state. We used a forward genetic screen to identify a CDK-related kinase, CDKR1, whose loss-of-function suppressed the shortening of cilia caused by overexpression of LF4A, by reducing its kinase activity. Loss of CDKR1 alone lengthened both the locomotory and oral cilia. CDKR1 resembles other known ciliary CDK-related kinases: LF2 of Chlamydomonas, mammalian CCRK and DYF-18 of C. elegans, in lacking the cyclin-binding motif and acting upstream of RCKs. The new genetic tools we developed here for Tetrahymena have potential for further dissection of the principles of cilia length regulation in multiciliated cells.

Inhibition of Osteocyte Membrane Repair Activity via Dietary Vitamin E Deprivation Impairs Osteocyte Survival.

Osteocytes experience plasma membrane disruptions (PMD) that initiate mechanotransduction both in vitro and in vivo in response to mechanical loading, suggesting that osteocytes use PMD to sense and adapt to mechanical stimuli. PMD repair is crucial for cell survival; antioxidants (e.g., alpha-tocopherol, also known as Vitamin E) promote repair while reactive oxygen species (ROS), which can accumulate during exercise, inhibit repair. The goal of this study was to determine whether depleting Vitamin E in the diet would impact osteocyte survival and bone adaptation with loading. Male CD-1 mice (3 weeks old) were fed either a regular diet (RD) or Vitamin E-deficient diet (VEDD) for up to 11 weeks. Mice from each dietary group either served as sedentary controls with normal cage activity, or were subjected to treadmill exercise (one bout of exercise or daily exercise for 5 weeks). VEDD-fed mice showed more PMD-affected osteocytes (+ 50%) after a single exercise bout suggesting impaired PMD repair following Vitamin E deprivation. After 5 weeks of daily exercise, VEDD mice failed to show an exercise-induced increase in osteocyte PMD formation, and showed signs of increased osteocytic oxidative stress and impaired osteocyte survival. Surprisingly, exercise-induced increases in cortical bone formation rate were only significant for VEDD-fed mice. This result may be consistent with previous studies in skeletal muscle, where myocyte PMD repair failure (e.g., with muscular dystrophy) initially triggers hypertrophy but later leads to widespread degeneration. In vitro, mechanically wounded MLO-Y4 cells displayed increased post-wounding necrosis (+ 40-fold) in the presence of H2O2, which could be prevented by Vitamin E pre-treatment. Taken together, our data support the idea that antioxidant-influenced osteocyte membrane repair is a vital aspect of bone mechanosensation in the osteocytic control of PMD-driven bone adaptation.

Failure to thrive, oral intake, and inpatient status prior to gastrostomy tube placement in the first year of life is associated with persistent use 1-year later.

BACKGROUND: Gastrostomy tube (GT) placement is a common procedure in infants (≤1-year-old). There is variation in patient selection and a paucity of studies examining which patients require long term enteral access. The objective of this study was to assess demographic and clinical factors associated with persistent GT use (PGU) at 1-year after placement. METHODS: We performed a single-institution retrospective review of patients ≤1-year-old who underwent GT placement from January 31, 2014, and January 31, 2020, using institutional NSQIP-P data supplemented with chart review. Multivariable logistic regression analysis was performed to identify factors associated with PGU. Clinical predictors were selected a priori, and a p-value less than 0.05 was used to detect a significant association. RESULTS: 140 patients were included, and 118 had a 1-year follow-up. At 1-year following GT placement, 38 patients had weaned from their GT (32.2%). Failure to thrive (FTT), and inpatient admission prior to surgery are associated with increased odds of PGU at 1-year after surgery, OR: 5.19 and 6.02, respectively. There is an inverse association between the percentage of feeds taken by mouth at the time of surgery and the odds of PGU at 1-year (OR: 0.03). CONCLUSION: Patients who have FTT (documented prior to surgery) or an inpatient admission prior to GT had a higher odds of PGU at 1-year post-op. Additionally, the amount taken by mouth at the time of GT placement was inversely related to PGU. These factors are important in determining the need for a surgical gastrostomy tube. LEVEL OF EVIDENCE: II.

Bradycardia resulting in cardiac arrest in a critically ill patient receiving dexmedetomidine.

Dexmedetomidine is an alpha-2 agonist sedative and analgesic used in anesthesia practice, and it has become more prevalent in the critically ill patients requiring short-term mechanical ventilation. While dexmedetomidine is known to have minimal effects on respiratory drive, it has been well-documented to cause bradycardia and hypotension, especially in patients with existing comorbidities. We present a patient without cardiovascular comorbidities who was in the surgical ICU under dexmedetomidine sedation. The patient went into asystole cardiac arrest after vagal stimulation. Return of spontaneous circulation was achieved using ACLS protocol. We offer a review of reported cases and make recommendations on the management of similar situations that may arise given the increasing use of dexmedetomidine.

A case report of a patient with gallbladder agenesis resulting in a common bile duct injury.

INTRODUCTION: Congenital agenesis of the gallbladder is a rare embryological defect of the biliary system. While occurring equally in men and women, gallbladder agenesis is found clinically twice as often in women. Patients present with symptoms suggesting biliary colic. Abdominal ultrasound and cholecintigraphy or HIDA scan are usually inconclusive and, in some cases, may be read as positive for biliary colic. Patients can undergo surgery based on characteristics of pain. PRESENTATION OF CASE: We report the case of a 60-year-old female presenting with symptoms of recurrent biliary colic and subsequently undergoing laparoscopic cholecystectomy after inconclusive workup. DISCUSSION: We offer a review of past reported cases as well as a new approach to such patients during the intraoperative period. An intraoperative decision should be made whether to continue and search for a possible ectopic gallbladder or investigate further with imaging studies. CONCLUSION: Gallbladder agenesis is a rare clinical presentation that the surgeon must be aware of. With inconclusive studies, the surgeon should consider congenital absence of the gallbladder and pursue further imaging if the gallbladder cannot be localized during the intraoperative period.

Mechanical loading disrupts osteocyte plasma membranes which initiates mechanosensation events in bone.

Osteocytes sense loading in bone, but their mechanosensation mechanisms remain poorly understood. Plasma membrane disruptions (PMD) develop with loading under physiological conditions in many cell types (e.g., myocytes, endothelial cells). These PMD foster molecular flux across cell membranes that promotes tissue adaptation, but this mechanosensation mechanism had not been explored in osteocytes. Our goal was to investigate whether PMD occur and initiate consequent mechanotransduction in osteocytes during physiological loading. We found that osteocytes experience PMD during in vitro (fluid flow) and in vivo (treadmill exercise) mechanical loading, in proportion to the level of stress experienced. In fluid flow studies, osteocyte PMD preferentially formed with rapid as compared to gradual application of loading. In treadmill studies, osteocyte PMD increased with loading in weight bearing locations (tibia), but this trend was not seen in non-weight bearing locations (skull). PMD initiated osteocyte mechanotransduction including calcium signaling and expression of c-fos, and repair rates of these PMD could be enhanced or inhibited pharmacologically to alter downstream mechanotransduction and osteocyte survival. PMD may represent a novel mechanosensation pathway in bone and a target for modifying skeletal adaptation signaling in osteocytes. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:653-662, 2018.