Knowledge and attitude towards the use of pain medications according to WHO cancer pain analgesic ladder in tertiary care hospitals of Pakistan.

To assess the knowledge and attitude of practicing physicians and surgeons towards the use of pain medication according to the World Health Organisation cancer pain analgesic ladder, the current study was conducted at tertiary care hospitals of the four provinces of Pakistan. Professionals having experience of treating cancer patients for >2 years were included. Data was collected using a self-administered questionnaire sent to each participant using Google Forms. Of the 630 physicians approached, 133(21%) responded. Of them, 74(55.64%) participants were familiar with the World Health Organisation analgesic ladder. There was a significant difference in the frequency of using the ladder based on age (p<0.05). Most participants 31(23%) reported the nonavailability of the recommended drugs as the reason for not following the analgesic ladder. There is a strong need to educate physicians and surgeons about the World Health Organisation analgesic ladder, and to make strategies to improve opioid availability in Pakistan.

Prophylactic Mesh Reinforcement for Non-Midline Incisions: A Systematic Review.

Background: Many abdominal-pelvic surgeries utilize incisions not along the linea alba, such as transverse, laparoscopic, ostomy reversal, or ostomy formation incisions. The prevalence of ventral incisional hernias (VIH) at these sites and the efficacy of prophylactic mesh in preventing VIH remains unclear. Methods: PubMed, Embase, Scopus, and Cochrane databases were systematically reviewed from inception to September 2022. We included published randomized controlled trials (RCTs) that compared prophylactic mesh reinforcement versus no mesh. The primary outcome was the incidence of VIH at postoperative follow-up equal to or greater than 24 months. Secondary outcomes included surgical site infection (SSI) and surgical site occurrence (SSO). Results: Of 3186 screened articles, only 3 RCTs with at least an 80% 2-year follow-up, encompassing a total of 901 patients, were included for analysis of non-midline VIH. Fifteen additional RCTs were included for analysis of secondary outcomes. The rate of parastomal hernias with prophylactic mesh was 21%, while it ranged from 44%-64% in the control group. The rate of incisional hernia after ostomy reversal with prophylactic mesh was 10%, and 16% in the control group. No clear evidence of a difference was found in rates of SSI or SSO between groups. Conclusion: There is limited evidence on the role of prophylactic mesh in preventing non-midline VIH. More studies at low risk for bias are needed to elucidate the balance of the long-term risks and benefits of prophylactic mesh for non-midline incisions.

Impact of Epidural Catheter-Incision Congruency on Postoperative Analgesia after Major Abdominal Surgery: An Observational Study in a Teaching Hospital.

OBJECTIVE: To determine the frequency of appropriate epidural catheter-incision congruency in adult patients undergoing major abdominal surgeries, as well as the frequency of ineffective postoperative analgesia with continuous epidural infusion, side effects, and complications of epidural insertion and epidural catheter infusion. STUDY DESIGN: Observational study. Place and Duration of the Study: Department of Anaesthesiology, The Aga Khan University Hospital, Karachi, Pakistan, from September to November 2022. METHODOLOGY: All adult patients who underwent elective major abdominal surgery under general anaesthesia with epidural analgesia were included in this study. Data were collected by chart review of the patients enrolled in Acute Pain Service for the study period. Intraoperative anaesthesia form, epidural infusion form and all records of acute pain service for the postoperative period were reviewed and recorded. RESULTS: One hundred and eighty-two patients were included in this study. The epidural catheter was inserted congruent to the surgical incision i.e. T10-T11 level or above in 43 (23.6%) patients only. In the postoperative period, overall effective epidural analgesia was observed in 79 (43.4%) of the patients. Motor block in lower limbs was observed in 66 (36.26%) of patients in the immediate postoperative period. CONCLUSION: The present study shows appropriate epidural catheter-incision congruency in only 23.6% of the patients. This could be one of the common reasons for ineffective postoperative pain relief via epidural analgesia in 56.6% of patients. KEY WORDS: Epidural catheter insertion site, Major abdominal surgeries, Postoperative analgesia.

EUS-guided radiofrequency ablation of solid pancreatic lesions: An updated review.

Recent years have brought to light newly developed therapeutic modalities for the treatment of premalignant and malignant pancreatic lesions. The role of EUS-guided radiofrequency ablation (EUS-RFA) as a treatment modality for malignant pancreatic lesions is still under evaluation. Several animal studies and human studies have demonstrated the safety and efficacy of EUS-RFA in the management of premalignant and malignant pancreatic lesions. EUS-RFA therapy can potentially ablate these lesions safely and with minimally invasive techniques. In this article, we provide an updated review of the application of EUS-RFA of pancreatic lesions. We also review the clinical efficacy and safety of this technique and future directions.

Infectious Extensor Tenosynovitis of the Hallucis Longus Tendon: A Case Report.

Infectious tenosynovitis can involve both flexor and extensor tendons of the extremities. If left untreated, it can lead to high morbidity and mortality. Most emergency providers recognize the signs and symptoms of flexor and extensor tenosynovitis of the hand. However, extensor tenosynovitis of the hallucis longus tendon is a rare condition with a risk of complications similar to infectious tenosynovitis of the hand. This case report describes a presentation of extensor tenosynovitis of the hallucis longus tendon. Clinical suspicion is essential to help the provider not miss this rare condition, which can lead to significant morbidity if not treated promptly or appropriately.

Age is a predictor of elbow stiffness after type III or IV supracondylar humerus fractures.

PURPOSE: Supracondylar humerus (SCH) fractures account for approximately 30% of injuries for those younger than 7 years of age (Cheng et al. in J Pediatr Orthop 19:344-350, 1999). Recent studies examining the association of patient age and SCH fracture outcomes have provided conflicting findings. The purpose of this study is to investigate SCH fracture outcomes in children at different ages of skeletal development. METHODS: Retrospective review of a Level I pediatric trauma center between 2010 and 2014 was conducted. 190 patients with SCH fractures, age < 14 years, fracture type Gartland III or IV (AO/OTA 13-M 3.1 III and IV) were included. Patients were sorted into age groups: < 2 years, 4-6 years, and > 8 years. Patients were treated with either a closed or open reduction with percutaneous fixation. Clinical outcomes including postoperative elbow range of motion, nerve palsy, compartment syndrome, infection, and cubitus varus were assessed. RESULTS: Patients in younger age groups were more likely to obtain postoperative full elbow flexion (< 2 years = 77%; 4-6 years = 66%; > 8 years = 43%) and full elbow extension (< 2 years = 96%; 4-6 years = 88%; > 8 years = 64%). Age was a significant predictor of nerve palsy on admission, mean operative time (< 2 years = 21.8 min; 4-6 years = 43.0 min; > 8 years = 80.7 min), and mean fluoroscopy time (< 2 years = 22.9 s; 4-6 years = 59.5 s; > 8 years = 171.9 s). There were no differences in rates of open reduction, compartment syndrome, pin tract infection, cubitus varus, or reoperation among groups. CONCLUSION: Increasing age is associated with increased elbow stiffness after percutaneous fixation of Gartland Type III and Type IV SCH fractures. Older patients with SCH fractures may benefit from formal rehabilitation. LEVEL OF EVIDENCE: III.

Mechanistic insight into the mode of inhibition of dietary flavonoids; targeting macrophage migration inhibitory factor.

Introduction: The Macrophage Migration Inhibitory Factor (MIF), a key pro-inflammatory mediator, is responsible for modulating immune responses. An array of inflammatory and autoimmune diseases has been linked to the dysregulated activity of MIF. The significance in physiological as well as pathophysiological phenomena underscores the potential of MIF as an attractive target with pharmacological relevance. Extensive research in past has uncovered a number of inhibitors, while the ISO-1, or (S, R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester being recognized as a benchmark standard so far. Recent work by Yang and coworkers identified five promising dietary flavonoids, with superior activity compared to the standard ISO-1. Nevertheless, the exact atomic-level inhibitory mechanism is still elusive. Methods: To improve the dynamic research, and rigorously characterize, and compare molecular signatures of MIF complexes with ISO-1 and flavonoids, principal component analysis (PCA) was linked with molecular dynamics (MD) simulations and binding free energy calculations. Results: The results suggest that by blocking the tautomerase site these small molecule inhibitors could modify the MIF activity by disrupting the intrinsic dynamics in particular functional areas. The stability matrices revealed the average deviation values ranging from 0.27-0.32 nm while the residue level fluctuations indicated that binding of the selected flavonoids confer enhanced stability relative to the ISO-1. Furthermore, the gyration values extracted from the simulated trajectories were found in the range of 1.80-1.83 nm. Discussion: Although all the tested flavonoids demonstrated remarkable results, the one obtained for the potent inhibitors, particularly Morin and Amentoflavone exhibited a good correlation with biological activity. The PCA results featured relatively less variance and constricted conformational landscape than others. The stable ensembles and reduced variation in turns might be the possible reasons for their outstanding performance documented previously. The results from the present exploration provide a comprehensive understanding of the molecular complexes formed by flavonoids and MIF, shedding light on their potential roles and impacts. Future studies on MIF inhibitors may benefit from the knowledge gathered from this investigation.

Mechanical Behavior of Selective Laser Melting (SLM) Parts with Varying Thicknesses in a Saline Environment under Different Exposure Times.

A promising method for additive manufacturing that makes it possible to produce intricate and personalized parts is selective laser melting (SLM). However, the mechanical properties of as-corroded SLM parts are still areas of concern. This research investigates the mechanical behavior of SLM parts that are exposed to a saline environment containing a 3.5% NaCl solution for varying lengths of time. The exposure times chosen for this study were 10 days, 20 days, and 30 days. The results reveal that the tensile strength of the parts is significantly affected by the duration of exposure. Additionally, the study also examined the influence of porosity on the corrosion behavior of the parts. The analysis included studying the mass loss of the parts over time, and a regression analysis was conducted to analyze the relationship between exposure time and mass loss. In addition, the utilization of scanning electron microscopy (SEM) and X-ray photo spectroscopy (XPS) techniques yielded valuable insights into the fundamental mechanisms accountable for the observed corrosion and mechanical behavior. It was found that the presence of corrosion products (i.e., oxide layer) and pitting contributed to the degradation of the SLM parts in the saline environment. This research emphasizes the importance of considering part thickness in the design of SLM components for corrosive environments and provides insights for enhancing their performance and durability.

Predicting FFAR4 agonists using structure-based machine learning approach based on molecular fingerprints.

Free Fatty Acid Receptor 4 (FFAR4), a G-protein-coupled receptor, is responsible for triggering intracellular signaling pathways that regulate various physiological processes. FFAR4 agonists are associated with enhancing insulin release and mitigating the atherogenic, obesogenic, pro-carcinogenic, and pro-diabetogenic effects, normally associated with the free fatty acids bound to FFAR4. In this research, molecular structure-based machine-learning techniques were employed to evaluate compounds as potential agonists for FFAR4. Molecular structures were encoded into bit arrays, serving as molecular fingerprints, which were subsequently analyzed using the Bayesian network algorithm to identify patterns for screening the data. The shortlisted hits obtained via machine learning protocols were further validated by Molecular Docking and via ADME and Toxicity predictions. The shortlisted compounds were then subjected to MD Simulations of the membrane-bound FFAR4-ligand complexes for 100 ns each. Molecular analyses, encompassing binding interactions, RMSD, RMSF, RoG, PCA, and FEL, were conducted to scrutinize the protein-ligand complexes at the inter-atomic level. The analyses revealed significant interactions of the shortlisted compounds with the crucial residues of FFAR4 previously documented. FFAR4 as part of the complexes demonstrated consistent RMSDs, ranging from 3.57 to 3.64, with minimal residue fluctuations 5.27 to 6.03 nm, suggesting stable complexes. The gyration values fluctuated between 22.8 to 23.5 nm, indicating structural compactness and orderliness across the studied systems. Additionally, distinct conformational motions were observed in each complex, with energy contours shifting to broader energy basins throughout the simulation, suggesting thermodynamically stable protein-ligand complexes. The two compounds CHEMBL2012662 and CHEMBL64616 are presented as potential FFAR4 agonists, based on these insights and in-depth analyses. Collectively, these findings advance our comprehension of FFAR4's functions and mechanisms, highlighting these compounds as potential FFAR4 agonists worthy of further exploration as innovative treatments for metabolic and immune-related conditions.

Pancreatic Walled-Off Necrosis: Cross-Sectional Imaging Depiction of Debris Predicts the Success of Endoscopic Drainage Using Lumen-Apposing Metal Stents.

INTRODUCTION: The use of endoscopic ultrasound (EUS)-guided transmural stent placement for pancreatic walled-off necrosis (WON) drainage is widespread. This study retrospectively analyzed imaging parameters predicting the outcomes of WON endoscopic drainage using lumen-apposing metal stents (LAMS). METHODS: This study analyzed the data of 115 patients who underwent EUS-guided debridement using LAMS from 2011 to 2015. Pre-intervention CT or MRI was used to analyze the total volume of WON, percentage of debris, multilocularity, and density. Success measures included technical success, the number of endoscopic sessions, the requirement of percutaneous drainage, long-term success, and recurrence. RESULTS: The primary cause of pancreatitis was gallstones (50.4%), followed by alcohol (27.8%), hypertriglyceridemia (11.3%), idiopathic (8.7%), and autoimmune (1.7%). The mean WON size was 674 mL. All patients underwent endoscopic necrosectomy, averaging 3.1 sessions. Stent placement was successful in 96.5% of cases. Procedural complications were observed in 13 patients (11.3%) and 6 patients (5.2%) who needed additional percutaneous drainage. No patients reported recurrent WON posttreatment. Univariate analysis indicated a significant correlation between debris percentage and the need for additional drainage and long-term success (p < 0.001). The number of endoscopic sessions correlated significantly with debris percentage (p < 0.001). CONCLUSION: Pre-procedural imaging, particularly debris percentage within WON, significantly predicts the number of endoscopic sessions, the need for further percutaneous drainage, and overall long-term success.

Lateralizing calcaneal osteotomy performed with a percutaneous burr results in a significantly lower increase in tarsal tunnel pressure.

PURPOSE: Tarsal tunnel syndrome is well documented following lateralizing calcaneal osteotomy to manage varus hindfoot deformity. Traditionally, calcaneal osteotomy is performed with an oscillating saw. No studies have investigated the effect of alternative surgical techniques on postoperative tarsal tunnel pressure. The purpose of this study was to investigate the difference in tarsal tunnel pressures following lateralizing calcaneal osteotomy performed using a high-torque, low-speed "minimally invasive surgery" (MIS) Shannon burr versus an oscillating saw. METHODS: Lateralizing calcaneal osteotomy was performed on 10 below-knee cadaveric specimens. This was conducted on 5 specimens each using an oscillating saw (Saw group) or MIS burr (Burr group). The calcaneal tuberosity was translated 1 cm laterally and transfixed using 2 Kirschner wires. Tarsal tunnel pressure was measured before and after osteotomy via ultrasound-guided percutaneous needle barometer. Mean pre/post-osteotomy pressures were compared between groups. Differences were analyzed using Student's t test. RESULTS: The mean pre-procedure tarsal tunnel pressure was 25.8 ± 5.1 mm Hg in the Saw group and 26.4 ± 4.3 mm Hg in the Burr group (p = 0.85). The mean post-procedure pressure was 63.4 ± 5.1 in the Saw group and 47.8 ± 4.3 in the Burr group (p = 0.01). Change in tarsal tunnel pressure was significantly lower in the Burr group (21.4 ± 4.5) compared to the Saw group (37.6 ± 12.5) (p = 0.03). The increase in tarsal tunnel pressure was 43% lower in the Burr group. CONCLUSION: In this cadaveric study, tarsal tunnel pressure increase after lateralizing calcaneal osteotomy was significantly lower when using a burr versus a saw. This is likely because the increased width ("kerf") of the 3 mm MIS burr, compared to the submillimeter saw blade width, causes calcaneal shortening. Given the smaller increase in tarsal tunnel pressure, using the MIS burr for lateralizing calcaneal osteotomy may decrease the risk of postoperative tarsal tunnel syndrome. Future research in vivo should explore this.

Uncovering PPAR-γ agonists: An integrated computational approach driven by machine learning.

Peroxisome proliferator-activated receptor gamma (PPAR-γ) serves as a nuclear receptor with a pivotal function in governing diverse facets of metabolic processes. In diabetes, the prime physiological role of PPAR-γ is to enhance insulin sensitivity and regulate glucose metabolism. Although PPAR-γ agonists such as Thiazolidinediones are effective in addressing diabetes complications, it is vital to be mindful that they are associated with substantial side effects that could potentially give rise to health challenges. The recent surge in the discovery of selective modulators of PPAR-γ inspired us to formulate an integrated computational strategy by leveraging the promising capabilities of both machine learning and in silico drug design approaches. In pursuit of our objectives, the initial stage of our work involved constructing an advanced machine learning classification model, which was trained utilizing chemical information and physicochemical descriptors obtained from known PPAR-γ modulators. The subsequent application of machine learning-based virtual screening, using a library of 31,750 compounds, allowed us to identify 68 compounds having suitable characteristics for further investigation. A total of four compounds were identified and the most favorable configurations were complemented with docking scores ranging from -8.0 to -9.1 kcal/mol. Additionally, the compounds engaged in hydrogen bond interactions with essential conserved residues including His323, Leu330, Phe363, His449 and Tyr473 that describe the ligand binding site. The stability indices investigated herein for instance root-mean-square fluctuations in the backbone atoms indicated higher mobility in the region of orthosteric site in the presence of agonist with the deviation peaks in the range of 0.07-0.69 nm, signifying moderate conformational changes. The deviations at global level revealed that the average values lie in the range of 0.25-0.32 nm. In conclusion, our identified hits particularly, CHEMBL-3185642 and CHEMBL-3554847 presented outstanding results and highlighted the stable conformation within the orthosteric site of PPAR-γ to positively modulate the activity.

Adjuvant Radiofrequency Ablation Along With Stenting Versus Stenting Alone for Biliary Tree Drainage in Patients With Malignant Biliary Strictures: A Systemic Review and Meta-analysis.

OBJECTIVE: This metanalysis aims to assess the efficacy and safety of biliary stenting along with radiofrequency ablation compared with stents alone to treat malignant biliary obstruction (MBO) due to extrahepatic biliary strictures secondary to cholangiocarcinoma, pancreatic cancer, and metastatic cancer. METHODS: A systemic search of major databases through April 2022 was done. All original studies were included comparing radiofrequency ablation with stenting versus stenting alone for treating malignant biliary strictures. The primary outcomes of interest were the difference in the mean stent patency and overall survival (OS) days between the 2 groups. The secondary outcome was to compare the adverse events of the 2 groups. The mean difference in the stent patency and OS days was pooled by using a random-effect model. We calculated the odds ratio to compare the adverse events between the 2 groups. RESULTS: A total of 13 studies with 1339 patients were identified. The pooled weighted mean difference in stent patency was 43.50 days (95% CI, 25.60-61.41), favoring the RFA plus stenting. Moreover, the pooled weighted mean difference in OS was 90.53 days (95% CI, 49.00-132.07), showing improved survival in the RFA group. Our analysis showed no statistically significant difference in adverse events between the 2 groups OR 1.13 (95% CI, 0.90-1.42). CONCLUSION: Our analysis showed that RFA, along with stent, is safe and is associated with improved stent patency and overall patient survival in malignant biliary strictures. More robust prospective studies should assess this association further.

International Consensus Recommendations for Safe Use of LAMS for On- and Off-Label Indications Using a Modified Delphi Process.

INTRODUCTION: The study aimed to develop international consensus recommendations on the safe use of lumen-apposing metal stents (LAMSs) for on- and off-label indications. METHODS: Based on the available literature, statements were formulated and grouped into the following categories: general safety measures, peripancreatic fluid collections, endoscopic ultrasound (EUS)-biliary drainage, EUS-gallbladder drainage, EUS-gastroenterostomy, and gastric access temporary for endoscopy. The evidence level of each statement was determined using the Grading of Recommendations Assessment, Development, and Evaluation methodology.International LAMS experts were invited to participate in a modified Delphi process. When no 80% consensus was reached, the statement was modified based on expert feedback. Statements were rejected if no consensus was reached after the third Delphi round. RESULTS: Fifty-six (93.3%) of 60 formulated statements were accepted, of which 35 (58.3%) in the first round. Consensus was reached on the optimal learning path, preprocedural imaging, the need for airway protection and essential safety measures during the procedure, such as the use of Doppler, and measurement of the distance between the gastrointestinal lumen and the target structure. Specific consensus recommendations were generated for the different LAMS indications, covering, among others, careful patient selection, the preferred size of the LAMS, the need for antibiotics, the preferred anatomic location of the LAMS, the need for coaxial pigtail placement, and the appropriate management of LAMS-related adverse events. DISCUSSION: Through a modified international Delphi process, we developed general and indication-specific experience- and evidence-based recommendations on the safe use of LAMS.

Safety and adverse events of EUS-guided gallbladder drainage using lumen-apposing metal stents and percutaneous cholecystostomy tubes: a systematic review and meta-analysis.

BACKGROUND AND AIMS: EUS-guided gallbladder drainage using lumen-apposing metal stents (EUS-GBD-LAMSs) and percutaneous cholecystostomy for gallbladder drainage (PTGBD) are the alternative treatment modalities in high-risk surgical patients with acute cholecystitis (AC). The aim of this study was to compare the safety of these procedures for AC in surgically suboptimal candidates. METHODS: Six studies compared the 2 groups' early, delayed, and overall adverse events; they also compared length of hospital stay, re-interventions, and re-admissions rate. A random effect model calculated odds ratios (ORs) with a 95% confidence interval (CI). RESULTS: The 2 groups had similar early adverse events; however, EUS-GBD-LAMS was associated with a lower rate of delayed (OR, .21; 95% CI, .07-.61; P ≤ .01) and overall (OR, .43; 95% CI, .30-.61; P ≤ .01) adverse events. Patients with EUS-GBD-LAMSs had a shorter hospital stay than PTGBD. CONCLUSIONS: EUS-GBD-LAMS is a safer option than PTGBD and is associated with a shorter hospital stay in nonsurgical candidates with AC.

Dedicated Early Morning Orthopaedic Trauma Operating Room Is Associated With Shorter Time to Surgery and Decreased Length of Hospital Stay for Children Undergoing Surgical Treatment of Supracondylar Humerus Fractures: A Retrospective Cohort Study.

INTRODUCTION: The purpose of this study was to investigate whether the use of a dedicated early morning orthopaedic trauma operating room (OR) resulted in shorter wait times, decreased surgical times, decreased length of stay (LOS), and decreased complications in children treated with urgent surgical intervention for supracondylar humerus fractures. METHODS: This retrospective comparative cohort study at a level I pediatric trauma center included patients younger than 12 years with supracondylar humerus fractures urgently treated with closed or open reduction and percutaneous pinning. Index surgical cases from April 28, 2013, to February 26, 2020, were included. Patients with prior humerus fracture, concomitant injuries, open fracture, pulseless supracondylar fracture, or missing data were excluded. Patients were analyzed based on the type of OR: dedicated early morning orthopaedic trauma OR or typical daytime orthopaedic OR. The primary outcome was time from presentation to surgery. Secondary outcomes included surgical time, complications, and LOS. RESULTS: A total of 401 patients with a mean age of 5 ± 2 (range: 1 to 11) years and a mean follow-up of 2.0 ± 2.1 (range: 0.5 to 25.0) months were included, of whom 137 patients (34%) underwent surgery in the early morning dedicated orthopaedic trauma OR. The dedicated early morning orthopaedic OR group had significantly less time from presentation to surgery (7.5 versus 9.4 hours; P = 0.0002) and shorter LOS (21.0 versus 24.0 hours; P = 0.004) compared with children treated in the typical daytime orthopaedic OR. Surgical time (31.1 versus 32.6 minutes; P = 0.40) and complication rates (5.8% versus 4.9%; P = 0.65) were similar between the groups. No revision surgery was required in either group. DISCUSSION: Surgical wait times were diminished with use of the dedicated early morning OR, as was LOS. Surgical times and complication rates were similar between groups. Institutions may consider adopting a dedicated early morning orthopaedic trauma OR to improve surgical wait times and decrease LOS. LEVEL OF EVIDENCE: III.

Arctic freshwater impact on the Atlantic Meridional Overturning Circulation: status and prospects.

Arguably, the most conspicuous evidence for anthropogenic climate change lies in the Arctic Ocean. For example, the summer-time Arctic sea ice extent has declined over the last 40 years and the Arctic Ocean freshwater storage has increased over the last 30 years. Coupled climate models project that this extra freshwater will pass Greenland to enter the sub-polar North Atlantic Ocean (SPNA) in the coming decades. Coupled climate models also project that the Atlantic Meridional Overturning Circulation (AMOC) will weaken in the twenty-first century, associated with SPNA buoyancy increases. Yet, it remains unclear when the Arctic anthropogenic freshening signal will be detected in the SPNA, or what form the signal will take. Therefore, this article reviews and synthesizes the state of knowledge on Arctic Ocean and SPNA salinity variations and their causes. This article focuses on the export processes in data-constrained ocean circulation model hindcasts. One challenge is to quantify and understand the relative importance of different competing processes. This article also discusses the prospects to detect the emergence of Arctic anthropogenic freshening and the likely impacts on the AMOC. For this issue, the challenge is to distinguish anthropogenic signals from natural variability. This article is part of a discussion meeting issue 'Atlantic overturning: new observations and challenges'.

Mesh Type With Ventral Hernia Repair: A Systematic Review and Meta-analysis of Randomized Trials.

INTRODUCTION: Synthetic mesh is widely utilized for clean ventral hernia repair; however, it is unclear if synthetic mesh provides the same benefits with high-risk patients or during contaminated cases. Many surgeons use biologic mesh in these settings, but there is little evidence to support this practice. Our objective was to compare the clinical outcomes of utilizing biologic mesh versus synthetic mesh during ventral hernia repair. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a review of the literature was conducted using Cochrane library, EMBASE, Clinicaltrials.gov, and PubMed for randomized controlled trials published that compared biologic versus synthetic mesh during ventral hernia repair. The primary outcome was major complications defined as deep or organ space surgical site infection, reoperations, and hernia recurrences. RESULTS: Of 1889 manuscripts screened, four publications were included. The four studies included a total of 758 patients, with 381 receiving biologic mesh and 377 receiving synthetic mesh. Compared to biologic mesh, synthetic mesh had lower rates of major complications (38.6% versus 23.4, risk ratio = 0.55, 95% confidence interval = 0.35 to 0.86, P = 0.009) and hernia recurrence (24.5 % versus 10.3%, risk ratio = 0.44, 95% confidence interval = 0.28 to 0.69, P = 0.004). In addition, there was a lower percentage of surgical site infection and reoperation in the synthetic mesh group. CONCLUSIONS: Contrary to current surgical teaching, placement of permanent synthetic mesh into a contaminated field yielded rates of complications that were comparable or reduced compared to biologic mesh.