Intestinal dysbiosis as an intraoperative predictor of septic complications: evidence from human surgical cohorts and preclinical models of peritoneal sepsis.

Major surgery exposes the intestinal microbiota to inflammatory and antibiotic stressors, which alter the microbiota composition of the intestinal lumen and fecal contents. However, it is not sufficiently understood, if such dysbiosis develops already during surgery and if alterations in microbiota may be the cause of surgical complications. End-of-surgery composition of the microbiota in the rectum was assessed in 41 patients undergoing either rectal or duodenopancreatic resection and was compared to baseline before surgery using 16S-rRNA sequencing. A subset of patients developed severe dysbiosis at the end of surgery, which was characterized by an overgrowth of the Proteobacteria phylum that includes the facultative pathogen E. coli. To test if dysbiosis impacts on surgical outcomes, dysbiosis was modeled in mice by a single oral administration of vancomycin prior to cecal ligation and puncture. Dysbiosis was associated with impaired post-surgical survival, dysregulation of the host's immune response, elevated bacterial virulence and reduced bacterial metabolism of carbon sources. In conclusion, dysbiosis can be detected already at the end of surgery in a fraction of patients undergoing major surgery. Modelling surgery-associated dysbiosis in mice using single-shot administration of vancomycin induced dysbiosis and resulted in elevated mortality.

Empyema after image-guided percutaneous intercostal drainage of subdiaphragmatic collection: a case series.

Background: Treatment of subdiaphragmatic collection by intercostal image-guided drain placement is associated with a risk of pleural complications including potentially life-threatening pleural empyema. Descriptions of patient characteristics and clinical course of postinterventional pleural empyema are lacking. We aim to present characteristics, clinical course and outcomes of patients with empyema after intercostal approach of drain placement. Methods: Data was collected as a retrospective single center case series and included adult patients with decortication for treatment of pleural empyema after image-guided percutaneous intercostal drainage of a subdiaphragmatic collection between 01.01.2009 and 31.01.2021. Results: We identified ten patients, nine male and one female, all suffering from subdiaphragmatic collection treated with intercostal drain. All patients developed pleural empyema after drain placement and received surgical decortication. Similarities between patients were drain placement under computed tomography (CT)-guidance (eight of ten patients), lateral position of the drain (seven of ten patients), drain insertion in the eighth intercostal space (ICS) (six of ten patients) and existing comorbidities as malnutrition (six of ten patients), diabetes (four of ten patients) and cancer (three of ten patients). The majority of patients had a prolonged length of hospital stay (LOS) with an average duration of 40 days. Nearly half of the patients needed intensive care unit (ICU) treatment and one patient died postoperatively from respiratory exhaustion. Conclusions: In this series, empyema after intercostal drainage was associated with prolonged LOS and was potentially life-threatening. The most commonly shared features in our cohort were the high prevalence of comorbidities, drain insertion above ninth ICS as well as lateral position of the drain. These factors should be addressed in prospective studies to evaluate potential correlation with postinterventional empyema. For optimal management of patients with subdiaphragmatic collection treated by intercostal drainage, awareness of potential associated complications is crucial.

No impact of sex on surgical site infections in abdominal surgery: a multi-center study.

OBJECTIVE: Male sex is controversially discussed as a risk factor for surgical site infections (SSI). The aim of the present study was to evaluate the impact of sex on SSI in abdominal surgery under elimination of relevant confounders. METHODS: Clinicopathological data of 6603 patients undergoing abdominal surgery from a multi-center prospective database of four Swiss hospitals including patients between 2015 and 2018 were assessed. Patients were stratified according to postoperative SSI and risk factors for SSI were identified using univariate and multivariate analysis. RESULTS: In 649 of 6603 patients, SSI was reported (9.8%). SSI was significantly associated with reoperation (22.7% vs. 3.4%, p < 0.001), increased mortality rate (4.6% vs. 0.9%, p < 0.001), and increased rate of length of hospital stay > 75th percentile (57.0% vs. 17.9%, p < 0.001). In univariate analysis, male sex was a significant risk factor for SSI (p = 0.01). In multivariate analysis including multiple confounders' such as comorbidities and perioperative factors, there was no association between male sex and risk of SSI (odds ratio (OR) 1.1 [CI 0.8-1.4]). Independent risk factors for SSI in multivariate analysis were BMI ≥ 30 kg/m2 (OR 1.8 [CI 1.3-2.3]), duration of surgery > 75th percentile (OR 2.3 [1.8-2.9]), high contamination level (OR 1.3 [1.0-1.6]), laparotomy (OR 1.3 [1.0-1.7]), previous laparotomy (OR 1.4 [1.1-1.7]), blood transfusion (OR 1.7 [1.2-2.4]), cancer (OR 1.3 [1.0-1.8] and malnutrition (OR 2.5 [1.8-3.4]). CONCLUSION: Under elimination of relevant confounders, there is no significant correlation between sex and risk of SSI after abdominal surgery.

Sterile Injury Repair and Adhesion Formation at Serosal Surfaces.

Most multicellular organisms have a major body cavity containing vital organs. This cavity is lined by a mucosa-like serosal surface and filled with serous fluid which suspends many immune cells. Injuries affecting the major body cavity are potentially life-threatening. Here we summarize evidence that unique damage detection and repair mechanisms have evolved to ensure immediate and swift repair of injuries at serosal surfaces. Furthermore, thousands of patients undergo surgery within the abdominal and thoracic cavities each day. While these surgeries are potentially lifesaving, some patients will suffer complications due to inappropriate scar formation when wound healing at serosal surfaces defects. These scars called adhesions cause profound challenges for health care systems and patients. Therefore, reviewing the mechanisms of wound repair at serosal surfaces is of clinical importance. Serosal surfaces will be introduced with a short embryological and microanatomical perspective followed by a discussion of the mechanisms of damage recognition and initiation of sterile inflammation at serosal surfaces. Distinct immune cells populations are free floating within the coelomic (peritoneal) cavity and contribute towards damage recognition and initiation of wound repair. We will highlight the emerging role of resident cavity GATA6+ macrophages in repairing serosal injuries and compare serosal (mesothelial) injuries with injuries to the blood vessel walls. This allows to draw some parallels such as the critical role of the mesothelium in regulating fibrin deposition and how peritoneal macrophages can aggregate in a platelet-like fashion in response to sterile injury. Then, we discuss how serosal wound healing can go wrong, causing adhesions. The current pathogenetic understanding of and potential future therapeutic avenues against adhesions are discussed.