Evidence-based surgery for laparoscopic cholecystectomy.

Background: Laparoscopic cholecystectomy is frequently performed for acute cholecystitis and symptomatic cholelithiasis. Considerable variation in the execution of key steps of the operation remains. We conducted a systematic review of evidence regarding best practices for critical intraoperative steps for laparoscopic cholecystectomy. Methods: We identified 5 main intraoperative decision points in laparoscopic cholecystectomy: (1) number and position of laparoscopic ports; (2) identification of cystic artery and duct; (3) division of cystic artery and duct; (4) indications for subtotal cholecystectomy; and (5) retrieval of the gallbladder. PubMed, EMBASE, and Web of Science were queried for relevant studies. Randomized controlled trials and systematic reviews were included for analysis, and evidence quality was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation framework. Results: Fifty-two articles were included. Although all port configurations were comparable from a safety standpoint, fewer ports sometimes resulted in improved cosmesis or decreased pain but longer operative times. The critical view of safety should be obtained for identification of the cystic duct and artery but may be obtained through fundus-first dissection and augmented with cholangiography or ultrasound. Insufficient evidence exists to compare harmonic-shear, clipless ligation against clip ligation of the cystic duct and artery. Stump closure during subtotal cholecystectomy may reduce rates of bile leak and reoperation. Use of retrieval bag for gallbladder extraction results in minimal benefit. Most studies were underpowered to detect differences in incidence of rare complications. Conclusion: Key operative steps of laparoscopic cholecystectomy should be informed by both compiled data and surgeon preference/patient considerations.

Evidence-based surgery for laparoscopic appendectomy: A stepwise systematic review.

INTRODUCTION: Appendectomy is a common emergency surgery performed globally. Despite the frequency of laparoscopic appendectomy, consensus does not exist on the best way to perform each procedural step. We identified literature on key intraoperative steps to inform best technical practice during laparoscopic appendectomy. METHODS: Research questions were framed using the population, indication, comparison, outcome (PICO) format for 6 key operative steps of laparoscopic appendectomy: abdominal entry, placement of laparoscopic ports, division of mesoappendix, division of appendix, removal of appendix, and fascial closure. These questions were used to build literature queries in PubMed, EMBASE, and the Cochrane Library databases. Evidence quality and certainty was assessed using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) definitions. RESULTS: Recommendations were rendered for 6 PICO questions based on 28 full length articles. Low quality evidence favors direct trocar insertion for abdominal entry and establishment of pneumoperitoneum. Single port appendectomy results in improved cosmesis with unclear clinical implications. There was insufficient data to determine the optimal method of appendiceal stump closure, but use of a specimen extraction bag reduces rates of superficial surgical site infection and intra-abdominal abscess. Port sites made with radially dilating trocars are less likely to necessitate closure and are less likely to result in port site hernia. When port sites are closed, a closure device should be used. CONCLUSION: Key operative steps of laparoscopic appendectomy have sufficient data to encourage standardized practice.

Mitohormesis reprogrammes macrophage metabolism to enforce tolerance.

Macrophages generate mitochondrial reactive oxygen species and mitochondrial reactive electrophilic species as antimicrobials during Toll-like receptor (TLR)-dependent inflammatory responses. Whether mitochondrial stress caused by these molecules impacts macrophage function is unknown. Here, we demonstrate that both pharmacologically driven and lipopolysaccharide (LPS)-driven mitochondrial stress in macrophages triggers a stress response called mitohormesis. LPS-driven mitohormetic stress adaptations occur as macrophages transition from an LPS-responsive to LPS-tolerant state wherein stimulus-induced pro-inflammatory gene transcription is impaired, suggesting tolerance is a product of mitohormesis. Indeed, like LPS, hydroxyoestrogen-triggered mitohormesis suppresses mitochondrial oxidative metabolism and acetyl-CoA production needed for histone acetylation and pro-inflammatory gene transcription, and is sufficient to enforce an LPS-tolerant state. Thus, mitochondrial reactive oxygen species and mitochondrial reactive electrophilic species are TLR-dependent signalling molecules that trigger mitohormesis as a negative feedback mechanism to restrain inflammation via tolerance. Moreover, bypassing TLR signalling and pharmacologically triggering mitohormesis represents a new anti-inflammatory strategy that co-opts this stress response to impair epigenetic support of pro-inflammatory gene transcription by mitochondria.