Low intraoperative end-tidal carbon dioxide levels are associated with improved recurrence-free survival after elective colorectal cancer surgery.

STUDY OBJECTIVE: Higher levels of carbon dioxide (CO2) increase the invasive abilities of colon cancer cells in vitro. Studies assessing target values for end-tidal CO2 concentrations (EtCO2) to improve surgical outcome after colorectal cancer surgery are lacking. Therefore, we evaluated whether intraoperative EtCO2 was associated with differences in recurrence-free survival after elective colorectal cancer (CRC) surgery. DESIGN: Single center, retrospective analysis. SETTING: Anesthesia records, surgical databases and hospital information system of a tertiary university hospital. PATIENTS: We analyzed 528 patients undergoing elective resection of colorectal cancer at Heidelberg University Hospital between 2009 and 2018. INTERVENTIONS: None. MEASUREMENTS: Intraoperative mean EtCO2 values were calculated. The study cohort was equally stratified into low-and high-EtCO2 groups. The primary endpoint measure was recurrence-free survival until last known follow-up. Groups were compared using Kaplan-Meier analysis. Cox-regression analysis was used to control for covariates. Sepsis, reoperations, surgical site infections and cardiovascular events during hospital stay, and overall survival were secondary outcomes. MAIN RESULTS: Mean EtCO2 was 33.8 mmHg ±1.2 in the low- EtCO2 group vs. 37.3 mmHg ±1.6 in the high-EtCO2 group. Median follow-up was 3.8 (Q1-Q3, 2.5-5.1) years. Recurrence-free survival was higher in the low-EtCO2 group (log-rank-test: p = .024). After correction for confounding factors, lower EtCO2 was associated with increased recurrence-free survival (HR = 1.138, 95%-CI:1.015-1.276, p = .027); the hazard for the primary outcome decreased by 12.1% per 1 mmHg decrease in mean EtCO2. 1-year and 5-year survival was also higher in the low-EtCO2 group. We did not find differences in the other secondary endpoints. CONCLUSIONS: Lower intraoperative EtCO2 target values in CRC surgery might benefit oncological outcome and should be evaluated in confirmative studies.

Cardiovascular-Kidney-Metabolic Syndrome: Association with Adverse Events After Major Noncardiac Surgery.

BACKGROUND: The American Heart Association (AHA) recently defined the cardiovascular-kidney-metabolic syndrome (CKM) as a new entity to address the complex interactions between heart, kidneys, and metabolism. The aim of this study was to assess the outcome impact of CKM syndrome in patients undergoing noncardiac surgery. METHODS: This is a secondary analysis of a prospective international cohort study including patients aged ≥45 years with increased cardiovascular risk undergoing noncardiac surgery. Main exposure was CKM syndrome according to the AHA definition. The primary end point was a composite of major adverse cardiovascular events (MACE) 30 days after surgery. Secondary end points included all-cause mortality and non-MACE complications (Clavien-Dindo class ≥3). RESULTS: This analysis included 14,634 patients (60.8% male, mean age = 72±8 years). MACE occurred in 308 patients (2.1%), and 335 patients (2.3%) died. MACE incidence by CKM stage was as follows: CKM 0: 5/367 = 1.4% (95% confidence interval [CI], 0.4%-3.2%); CKM 1: 3/367 = 0.8% (95% CI, 0.2%-2.4%); CKM 2: 102/7440 = 1.4% (95% CI, 1.1%-1.7%); CKM 3: 27/953 = 2.8% (95% CI, 1.9%-4.1%); CKM 4a: 164/5357 = 3.1% (95% CI, 2.6%-3.6%); CKM 4b: 7/150 = 4.7% (95% CI, 1.9%-9.4%). In multivariate logistic regression, CKM stage ≥3 was independently associated with MACE, mortality, and non-MACE complications, respectively (MACE: OR 2.26 [95% CI, 1.78-2.87]; mortality: OR 1.42 [95% CI: 1.13 -1.78]; non-MACE complications: OR 1.11 [95% CI: 1.03-1.20]). CONCLUSION: The newly defined CKM syndrome is associated with increased morbidity and mortality after non-cardiac surgery. Thus, cardiovascular, renal, and metabolic disorders should be regarded in mutual context in this setting.

Thoracic Epidural Analgesia Is Not Associated With Improved Survival After Pancreatic Surgery: Long-Term Follow-Up of the Randomized Controlled PAKMAN Trial.

BACKGROUND: Perioperative thoracic epidural analgesia (EDA) and patient-controlled intravenous analgesia (PCIA) are common forms of analgesia after pancreatic surgery. Current guidelines recommend EDA over PCIA, and evidence suggests that EDA may improve long-term survival after surgery, especially in cancer patients. The aim of this study was to determine whether perioperative EDA is associated with an improved patient prognosis compared to PCIA in pancreatic surgery. METHODS: The PAKMAN trial was an adaptive, pragmatic, international, multicenter, randomized controlled superiority trial conducted from June 2015 to October 2017. Three to five years after index surgery a long-term follow-up was performed from October 2020 to April 2021. RESULTS: For long-term follow-up of survival, 109 patients with EDA were compared to 111 patients with PCIA after partial pancreatoduodenectomy (PD). Long-term follow-up of quality of life (QoL) and pain assessment was available for 40 patients with EDA and 45 patients with PCIA (questionnaire response rate: 94%). Survival analysis revealed that EDA, when compared to PCIA, was not associated with improved overall survival (OS, HR, 1.176, 95% HR-CI, 0.809-1.710, P = .397, n = 220). Likewise, recurrence-free survival did not differ between groups (HR, 1.116, 95% HR-CI, 0.817-1.664, P = .397, n = 220). OS subgroup analysis including only patients with malignancies showed no significant difference between EDA and PCIA (HR, 1.369, 95% HR-CI, 0.932-2.011, P = .109, n = 179). Similar long-term effects on QoL and pain severity were observed in both groups (EDA: n = 40, PCIA: n = 45). CONCLUSIONS: Results from this long-term follow-up of the PAKMAN randomized controlled trial do not support favoring EDA over PCIA in pancreatic surgery. Until further evidence is available, EDA and PCIA should be considered similar regarding long-term survival.

NT-proBNP or Self-Reported Functional Capacity in Estimating Risk of Cardiovascular Events After Noncardiac Surgery.

Importance: Nearly 16 million surgical procedures are conducted in North America yearly, and postoperative cardiovascular events are frequent. Guidelines suggest functional capacity or B-type natriuretic peptides (BNP) to guide perioperative management. Data comparing the performance of these approaches are scarce. Objective: To compare the addition of either N-terminal pro-BNP (NT-proBNP) or self-reported functional capacity to clinical scores to estimate the risk of major adverse cardiac events (MACE). Design, Setting, and Participants: This cohort study included patients undergoing inpatient, elective, noncardiac surgery at 25 tertiary care hospitals in Europe between June 2017 and April 2020. Analysis was conducted in January 2023. Eligible patients were either aged 45 years or older with a Revised Cardiac Risk Index (RCRI) of 2 or higher or a National Surgical Quality Improvement Program, Risk Calculator for Myocardial Infarction and Cardiac (NSQIP MICA) above 1%, or they were aged 65 years or older and underwent intermediate or high-risk procedures. Exposures: Preoperative NT-proBNP and the following self-reported measures of functional capacity were the exposures: (1) questionnaire-estimated metabolic equivalents (METs), (2) ability to climb 1 floor, and (3) level of regular physical activity. Main Outcome and Measures: MACE was defined as a composite end point of in-hospital cardiovascular mortality, cardiac arrest, myocardial infarction, stroke, and congestive heart failure requiring transfer to a higher unit of care. Results: A total of 3731 eligible patients undergoing noncardiac surgery were analyzed; 3597 patients had complete data (1258 women [35.0%]; 1463 (40.7%) aged 75 years or older; 86 [2.4%] experienced a MACE). Discrimination of NT-proBNP or functional capacity measures added to clinical scores did not significantly differ (Area under the receiver operating curve: RCRI, age, and 4MET, 0.704; 95% CI, 0.646-0.763; RCRI, age, and 4MET plus floor climbing, 0.702; 95% CI, 0.645-0.760; RCRI, age, and 4MET plus physical activity, 0.724; 95% CI, 0.672-0.775; RCRI, age, and 4MET plus NT-proBNP, 0.736; 95% CI, 0.682-0.790). Benefit analysis favored NT-proBNP at a threshold of 5% or below, ie, if true positives were valued 20 times or more compared with false positives. The findings were similar for NSQIP MICA as baseline clinical scores. Conclusions and relevance: In this cohort study of nearly 3600 patients with elevated cardiovascular risk undergoing noncardiac surgery, there was no conclusive evidence of a difference between a NT-proBNP-based and a self-reported functional capacity-based estimate of MACE risk. Trial Registration: ClinicalTrials.gov Identifier: NCT03016936.

Abdominal surgery induces long-lasting changes in expression and binding of CTCF with impact on Major Histocompatibility Complex II transcription in circulating human monocytes.

BACKGROUND: Postoperative immunosuppression has been recognized as an important driver of surgery-related morbidity and mortality. It is characterized by lymphocyte depression and impaired monocyte capability to present foreign antigens to T-cells via Major Histocompatibility Complex, Class II (MHC-II) molecules. In patients with postoperative abdominal sepsis, we previously detected a persisting differential binding of the CCCTC-Binding Factor (CTCF), a superordinate regulator of transcription, inside the MHC-II region with specific impact on human leucocyte antigen (HLA) gene expression. In this prospective exploratory study, we investigated to which extent major surgery affects the MHC-II region of circulating CD14+-monocytes. RESULTS: In non-immunocompromised patients undergoing elective major abdominal surgery, a postoperative loss of monocyte HLA-DR surface receptor density was accompanied by a decline in the transcription levels of the classical MHC-II genes HLA-DRA, HLA-DRB1, HLA-DPA1 and HLA-DPB1. The surgical event decreased the expression of the transcriptional MHC-II regulators CIITA and CTCF and led to a lower CTCF enrichment at an intergenic sequence within the HLA-DR subregion. During the observation period, we found a slow and only incomplete restoration of monocyte HLA-DR surface receptor density as well as a partial recovery of CIITA, HLA-DRA and HLA-DRB1 expression. In contrast, transcription of HLA-DPA1, HLA-DPB1, CTCF and binding of CTCF within the MHC-II remained altered. CONCLUSION: In circulating monocytes, major surgery does not globally affect MHC-II transcription but rather induces specific changes in the expression of selected HLA genes, followed by differential recovery patterns and accompanied by a prolonged reduction of CTCF expression and binding within the MHC-II region. Our results hint toward a long-lasting impact of a major surgical intervention on monocyte functionality, possibly mediated by epigenetic changes that endure the life span of the individual cell.

Risk assessment for major adverse cardiovascular events after noncardiac surgery using self-reported functional capacity: international prospective cohort study.

BACKGROUND: Guidelines endorse self-reported functional capacity for preoperative cardiovascular assessment, although evidence for its predictive value is inconsistent. We hypothesised that self-reported effort tolerance improves prediction of major adverse cardiovascular events (MACEs) after noncardiac surgery. METHODS: This is an international prospective cohort study (June 2017 to April 2020) in patients undergoing elective noncardiac surgery at elevated cardiovascular risk. Exposures were (i) questionnaire-estimated effort tolerance in metabolic equivalents (METs), (ii) number of floors climbed without resting, (iii) self-perceived cardiopulmonary fitness compared with peers, and (iv) level of regularly performed physical activity. The primary endpoint was in-hospital MACE consisting of cardiovascular mortality, non-fatal cardiac arrest, acute myocardial infarction, stroke, and congestive heart failure requiring transfer to a higher unit of care or resulting in a prolongation of stay on ICU/intermediate care (≥24 h). Mixed-effects logistic regression models were calculated. RESULTS: In this study, 274 (1.8%) of 15 406 patients experienced MACE. Loss of follow-up was 2%. All self-reported functional capacity measures were independently associated with MACE but did not improve discrimination (area under the curve of receiver operating characteristic [ROC AUC]) over an internal clinical risk model (ROC AUCbaseline 0.74 [0.71-0.77], ROC AUCbaseline+4METs 0.74 [0.71-0.77], ROC AUCbaseline+floors climbed 0.75 [0.71-0.78], AUCbaseline+fitnessvspeers 0.74 [0.71-0.77], and AUCbaseline+physical activity 0.75 [0.72-0.78]). CONCLUSIONS: Assessment of self-reported functional capacity expressed in METs or using the other measures assessed here did not improve prognostic accuracy compared with clinical risk factors. Caution is needed in the use of self-reported functional capacity to guide clinical decisions resulting from risk assessment in patients undergoing noncardiac surgery. CLINICAL TRIAL REGISTRATION: NCT03016936.

Biomarker-guided intervention to prevent acute kidney injury after major surgery (BigpAK-2 trial): study protocol for an international, prospective, randomised controlled multicentre trial.

INTRODUCTION: Previous studies demonstrated that the implementation of the Kidney Disease Improving Global Outcomes (KDIGO) guideline-based bundle, consisting of different supportive measures in patients at high risk for acute kidney injury (AKI), might reduce rate and severity of AKI after surgery. However, the effects of the care bundle in broader population of patients undergoing surgery require confirmation. METHODS AND ANALYSIS: The BigpAK-2 trial is an international, randomised, controlled, multicentre trial. The trial aims to enrol 1302 patients undergoing major surgery who are subsequently admitted to the intensive care or high dependency unit and are at high-risk for postoperative AKI as identified by urinary biomarkers (tissue inhibitor of metalloproteinases 2*insulin like growth factor binding protein 7 (TIMP-2)*IGFBP7)). Eligible patients will be randomised to receive either standard of care (control) or a KDIGO-based AKI care bundle (intervention). The primary endpoint is the incidence of moderate or severe AKI (stage 2 or 3) within 72 hours after surgery, according to the KDIGO 2012 criteria. Secondary endpoints include adherence to the KDIGO care bundle, occurrence and severity of any stage of AKI, change in biomarker values during 12 hours after initial measurement of (TIMP-2)*(IGFBP7), number of free days of mechanical ventilation and vasopressors, need for renal replacement therapy (RRT), duration of RRT, renal recovery, 30-day and 60-day mortality, intensive care unit length-of-stay and hospital length-of-stay and major adverse kidney events. An add-on study will investigate blood and urine samples from recruited patients for immunological functions and kidney damage. ETHICS AND DISSEMINATION: The BigpAK-2 trial was approved by the Ethics Committee of the Medical Faculty of the University of Münster and subsequently by the corresponding Ethics Committee of the participating sites. A study amendment was approved subsequently. In the UK, the trial was adopted as an NIHR portfolio study. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and will guide patient care and further research. TRIAL REGISTRATION NUMBER: NCT04647396.

[Anesthesia in spinal surgery]. / Anästhesie bei Wirbelsäulenoperationen.

Over the past 20 years improvements in surgical techniques and perioperative patient care have led to a considerable increase in surgical procedures of the spine worldwide. Therefore, the spectrum was extended from minimally invasive procedures up to complex operations over several segments of the spinal column with high loss of blood and complex perioperative management. This article presents the principal pillars of preoperative, intraoperative and postoperative management relating to spinal surgery. Furthermore, procedure-specific features, such as airway management in cervical spine instability or implementation of intraoperative neuromonitoring are dealt with in detail.

Perioperative prothrombin complex concentrate and fibrinogen administration are associated with thrombotic complications after liver transplant.

Background: Use of intraoperative prothrombin complex concentrates (PCC) and fibrinogen concentrate administration has been linked to thrombotic events. However, it is unknown if its use is associated with thrombotic events after liver transplant. Methods and analysis: We conducted a post hoc analysis of a prospectively conducted registry database study on patients who underwent liver transplant between 2004 and 2017 at Heidelberg University Hospital, Heidelberg, Germany. Univariate and multivariate analyses were used to determine the association between PCC and fibrinogen concentrate administration and thrombotic complications. Results: Data from 939 transplantations were included in the analysis. Perioperative PCC or fibrinogen administration was independently associated with the primary composite endpoint Hepatic artery thrombosis (HAT), Portal vein thrombosis (PVT), and inferior vena cava thrombosis [adjusted HR: 2.018 (1.174; 3.468), p = 0.011]. PCC or fibrinogen administration was associated with the secondary endpoints 30-day mortality (OR 4.225, p < 0.001), graft failure (OR 3.093, p < 0.001), intraoperative blood loss, red blood cell concentrate, fresh frozen plasma and platelet transfusion, longer hospitalization, and longer length of stay in intensive care units (ICUs) (all p < 0.001). PCC or fibrinogen administration were not associated with pulmonary embolism, myocardial infarction, stroke, or deep vein thrombosis within 30 days after surgery. Conclusion: A critical review of established strategies in coagulation management during liver transplantation is warranted. Perioperative caregivers should exercise caution when administering coagulation factor concentrate during liver transplant surgery. Prospective randomized controlled trials are needed to establish causality for the relationship between coagulation factors and thrombotic events in liver transplantation. Further studies should be tailored to identify patient subgroups that will likely benefit from PCC or fibrinogen administration.

Study protocol of REpeat versus SIngle ShoT Antibiotic prophylaxis in major Abdominal Surgery (RESISTAAS I): a prospective observational study of antibiotic prophylaxis practice for patients undergoing major abdominal surgery.

INTRODUCTION: Surgical site infections (SSIs) are among the most common complications after abdominal surgery and develop in approximately 20% of patients. These patients suffer a 12% increase in mortality, underlying the need for strategies reducing SSI. Perioperative antibiotic prophylaxis is paramount for SSI prevention in major abdominal surgery. Yet, intraoperative redosing criteria are subjective and whether patients benefit from it remains unclear. METHODS AND ANALYSIS: The REpeat versus SIngle ShoT Antibiotic prophylaxis in major Abdominal Surgery (RESISTAAS I) study is a single-centre, prospective, observational study investigating redosing of antibiotic prophylaxis in 300 patients undergoing major abdominal surgery. Adult patients scheduled for major abdominal surgery will be included. Current practice of redosing regarding number and time period will be recorded. Postoperative SSIs, nosocomial infections, clinically relevant infection-associated bacteria, postoperative antibiotic treatment, in addition to other clinical, pharmacological and economical outcomes will be evaluated. Differences between groups will be analysed with analysis of covariance. ETHICS AND DISSEMINATION: RESISTAAS I will be conducted in accordance with the Declaration of Helsinki and internal, national and international standards of GCP. The Medical Ethics Review Board of Heidelberg University has approved the study prior to initiation (S-404/2021). The study has been registered on 7 February 2022 at German Clinical Trials Register, with identifier DRKS00027892. We plan to disseminate the results of the study in a peer-reviewed journal. TRIAL REGISTRATION: German Clinical Trials Register (DRKS): DRKS00027892.

Editor's Choice - Association Between Peri-OPerative Aspirin ResisTance and CardioVascular Outcome (POPART-CVO): a Prospective Non-Interventional Cohort Study.

OBJECTIVE: New onset aspirin resistance during surgery, known as peri-operative aspirin resistance, is observed in up to 30% of vascular surgery patients and is associated with post-operative myocardial damage; questioning aspirin effectiveness towards peri-operative cardiovascular events. The objective of this study was to prospectively evaluate whether peri-operative aspirin resistance in vascular surgery is associated with an adverse cardiovascular outcome. METHODS: Based on a sample size calculation, 194 adult elective vascular or endovascular surgery patients receiving aspirin were analysed in this prospective, single centred, non-interventional cohort study. Platelet function was measured before surgery, one hour after incision, four hours post-operatively, and on the morning of the first and second post-operative days using the Multiplate analyser. The primary outcome was myocardial injury after non-cardiac surgery (MINS). Secondary outcomes included major bleeding, admission to intensive care unit, length of hospital stay, and major adverse cardiac and cerebrovascular events. Subgroup analyses were performed for patients with different cardiovascular risk and for patients who underwent endovascular surgery. RESULTS: Peri-operative aspirin resistance was observed in 27.8% of patients but was not associated with MINS (27.8% vs. 32.1%, aspirin resistance vs. no aspirin resistance, OR 0.812, 95% CI 0.406 - 1.624, p = .56) or with any of the secondary endpoints (all p > .050). In nine of the 10 subgroup analyses, aspirin resistance was not associated with a difference in MINS rate. However, in patients with a low cardiovascular risk profile (RCRI 0-2), MINS occurred more frequently in patients without aspirin resistance (p = .049). CONCLUSION: This study confirmed previous reports demonstrating that peri-operative aspirin resistance is common in patients undergoing vascular or endovascular surgery. However, in patients who continue aspirin throughout the peri-operative period, aspirin resistance is a phenomenon, which does not appear to be related to MINS. Measuring peri-operative platelet function using the Multiplate analyser with the intention to identify and potentially prevent or treat peri-operative aspirin resistance seems to be dispensable.

Effect of Intraoperative Handovers of Anesthesia Care on Mortality, Readmission, or Postoperative Complications Among Adults: The HandiCAP Randomized Clinical Trial.

Importance: Intraoperative handovers of anesthesia care are common. Handovers might improve care by reducing physician fatigue, but there is also an inherent risk of losing critical information. Large observational analyses report associations between handover of anesthesia care and adverse events, including higher mortality. Objective: To determine the effect of handovers of anesthesia care on postoperative morbidity and mortality. Design, Setting, and Participants: This was a parallel-group, randomized clinical trial conducted in 12 German centers with patients enrolled between June 2019 and June 2021 (final follow-up, July 31, 2021). Eligible participants had an American Society of Anesthesiologists physical status 3 or 4 and were scheduled for major inpatient surgery expected to last at least 2 hours. Interventions: A total of 1817 participants were randomized to receive either a complete handover to receive anesthesia care by another clinician (n = 908) or no handover of anesthesia care (n = 909). None of the participating institutions used a standardized handover protocol. Main Outcomes and Measures: The primary outcome was a 30-day composite of all-cause mortality, hospital readmission, or serious postoperative complications. There were 19 secondary outcomes, including the components of the primary composite, along with intensive care unit and hospital lengths of stay. Results: Among 1817 randomized patients, 1772 (98%; mean age, 66 [SD, 12] years; 997 men [56%]; and 1717 [97%] with an American Society of Anesthesiologists physical status of 3) completed the trial. The median total duration of anesthesia was 267 minutes (IQR, 206-351 minutes), and the median time from start of anesthesia to first handover was 144 minutes in the handover group (IQR, 105-213 minutes). The composite primary outcome occurred in 268 of 891 patients (30%) in the handover group and in 284 of 881 (33%) in the no handover group (absolute risk difference [RD], -2.5%; 95% CI, -6.8% to 1.9%; odds ratio [OR], 0.89; 95% CI, 0.72 to 1.10; P = .27). Nineteen of 889 patients (2.1%) in the handover group and 30 of 873 (3.4%) in the no handover group experienced all-cause 30-day mortality (absolute RD, -1.3%; 95% CI, -2.8% to 0.2%; OR, 0.61; 95% CI, 0.34 to 1.10; P = .11); 115 of 888 (13%) vs 136 of 872 (16%) were readmitted to the hospital (absolute RD, -2.7%; 95% CI, -5.9% to 0.6%; OR, 0.80; 95% CI, 0.61 to 1.05; P = .12); and 195 of 890 (22%) vs 189 of 874 (22%) experienced serious postoperative complications (absolute RD, 0.3%; 95% CI, -3.6% to 4.1%; odds ratio, 1.02; 95% CI, 0.81 to 1.28; P = .91). None of the 19 prespecified secondary end points differed significantly. Conclusions and Relevance: Among adults undergoing extended surgical procedures, there was no significant difference between the patients randomized to receive handover of anesthesia care from one clinician to another, compared with the no handover group, in the composite primary outcome of mortality, readmission, or serious postoperative complications within 30 days. Trial Registration: ClinicalTrials.gov Identifier: NCT04016454.

Routine Postoperative Antibiotic Prophylaxis Offers No Benefit after Hepatectomy-A Systematic Review and Meta-Analysis.

BACKGROUND: Prophylactic antibiotics are frequently administered after major abdominal surgery including hepatectomies aiming to prevent infective complications. Yet, excessive use of antibiotics increases resistance in bacteria. The aim of this systematic review and meta-analysis is to assess the efficacy of prophylactic antibiotics after hepatectomy (postoperative antibiotic prophylaxis, POA). METHOD: This systematic review and meta-analysis were completed according to the current PRISMA guidelines. The protocol has been registered prior to data extraction (PROSPERO registration Nr: CRD42021288510). MEDLINE, Web of Science and CENTRAL were searched for clinical reports on POA in hepatectomy restrictions. A random-effects model was used for synthesis. Methodological quality was assessed with RoB2 and ROBINS-I. GRADE was used for the quality of evidence assessment. RESULTS: Nine comparative studies comprising 2987 patients were identified: six randomized controlled trials (RCTs) and three retrospectives. POA did not lead to a reduction in postoperative infective complications or have an effect on liver-specific complications-post-hepatectomy liver failure and biliary leaks. POA over four or more days was associated with increased rates of deep surgical site infections compared to short-term administration for up to two days (OR 1.54; 95% CI [1.17;2.03]; p = 0.03). Routine POA led to significantly higher MRSA incidence as a pathogen (p = 0.0073). Overall, the risk of bias in the studies was low and the quality of evidence moderate. CONCLUSION: Routine POA cannot be recommended after hepatectomy since it does not reduce postoperative infection or liver-specific complications but contributes to resistance in bacteria. Studies into individualized risk-adapted antibiotic prophylaxis strategies are needed to further optimize perioperative treatment in liver surgery.

Biomarkers and Cellular Biology in Perioperative Medicine.

Surgical procedures alter tissue integrity; are associated with pain and activation of the sympathetic nervous system; and sometimes, cause exposure to foreign materials used during the surgery or implanted perioperatively [...].

Intraoperative visualisation of pancreatic leakage (ViP): study protocol for an IDEAL Stage I Post Market Clinical Study.

INTRODUCTION: Pancreatic resections are an important field of surgery worldwide to treat a variety of benign and malignant diseases. Postoperative pancreatic fistula (POPF) remains a frequent and critical complication after partial pancreatectomy and affects up to 50% of patients. POPF increases mortality, prolongs the postoperative hospital stay and is associated with a significant economic burden. Despite various scientific approaches and clinical strategies, it has not yet been possible to develop an effective preventive tool. The SmartPAN indicator is the first surgery-ready medical device for direct visualisation of pancreatic leakage already during the operation. Applied to the surface of pancreatic tissue, it detects sites of biochemical leak via colour reaction, thereby guiding effective closure and potentially mitigating POPF development. METHODS AND ANALYSIS: The ViP trial is a prospective single-arm, single-centre first in human study to collect data on usability and confirm safety of SmartPAN. A total of 35 patients with planned partial pancreatectomy will be included in the trial with a follow-up of 30 days after the index surgery. Usability endpoints such as adherence to protocol and evaluation by the operating surgeon as well as safety parameters including major intraoperative and postoperative complications, especially POPF development, will be analysed. ETHICS AND DISSEMINATION: Following the IDEAL-D (Idea, Development, Exploration, Assessment, and Long term study of Device development and surgical innovation) framework of medical device development preclinical in vitro, porcine in vivo, and human ex vivo studies have proven feasibility, efficacy and safety of SmartPAN. After market approval, the ViP trial is the IDEAL Stage I trial to investigate SmartPAN in a clinical setting. The study has been approved by the local ethics committee as the device is used exclusively within its intended purpose. Results will be published in a peer-reviewed journal. The study will provide a basis for a future randomised controlled interventional trial to confirm clinical efficacy of SmartPAN. TRIAL REGISTRATION NUMBER: German Clinical Trial Register DRKS00027559, registered on 4 March 2022.

Intraoperative Fractions of Inspiratory Oxygen Are Associated With Recurrence-Free Survival After Elective Cancer Surgery.

Background: Choice of the fraction of inspiratory oxygen (FiO2) is controversial. The objective of this analysis was to evaluate whether intraoperative FiO2 was associated with recurrence-free survival after elective cancer surgery. Methods and Analysis: In this single-center, retrospective study, we analyzed 1,084 patients undergoing elective resection of pancreatic (n = 652), colorectal (n = 405), or hepatic cancer (n = 27) at Heidelberg University Hospital between 2009 and 2016. Intraoperative mean FiO2 values were calculated. For unstratified analyses, the study cohort was equally divided into a low- and a high-FiO2 group. For cancer-stratified analyses, this division was done within cancer-strata. The primary outcome measure was recurrence-free survival until the last known follow-up. Groups were compared using Kaplan-Meier analysis. A stratified log rank test was used to control for different FiO2 levels and survival times between the cancer strata. Cox-regression analyses were used to control for covariates. Sepsis, reoperations, surgical-site infections, and cardiovascular events during hospital stay and overall survival were secondary outcomes. Results: Median FiO2 was 40.9% (Q1-Q3, 38.3-42.9) in the low vs. 50.4% (Q1-Q3, 47.4-54.7) in the high-FiO2 group. Median follow-up was 3.28 (Q1-Q3, 1.68-4.97) years. Recurrence-free survival was considerable higher in the high-FiO2 group (p < 0.001). This effect was also confirmed when stratified for the different tumor entities (p = 0.007). In colorectal cancer surgery, increased FiO2 was independently associated with increased recurrence-free survival. The hazard for the primary outcome decreased by 3.5% with every 1% increase in FiO2. The effect was not seen in pancreatic cancer surgery and we did not find differences in any of the secondary endpoints. Conclusions: Until definite evidence from large-scale trials is available and in the absence of relevant clinical conditions warranting specific FiO2 values, perioperative care givers should aim for an intraoperative FiO2 of 50% in abdominal cancer surgery as this might benefit oncological outcomes.

Modulation of Peripheral CD4+CD25+Foxp3+ Regulatory T Cells Ameliorates Surgical Stress-Induced Atherosclerotic Plaque Progression in ApoE-Deficient Mice.

Systemic inflammation associated with major surgery rapidly accelerates atherosclerotic plaque progression in mice. Regulatory T cells (Tregs) have emerged as important modulators of atherogenesis. In coronary artery disease patients, low frequency of Tregs constitutes an independent risk factor for cardiovascular complications after non-cardiac surgery. In this exploratory analysis, we investigate whether preoperative Treg levels affect surgery-induced atherosclerotic lesion destabilization in a murine model of perioperative stress. After 9 weeks of high-cholesterol diet, atherosclerotic apolipoprotein E-deficient mice with modulated Treg levels were subjected to a 30-minute surgical procedure consisting of general isoflurane anesthesia, laparotomy and moderate blood loss. Controls underwent general anesthesia only. Brachiocephalic arteries were harvested 3 days after the intervention for histomorphological analyses of atherosclerotic plaques. Tregs were depleted by a single dose of anti-CD25 monoclonal antibody (mAb) administered 6 days prior to the intervention. Expansion of Tregs was induced by daily injections of IL-2/anti-IL-2 complex (IL-2C) on three consecutive days starting 3 days before surgery. Isotype-matched antibodies and PBS served as controls. Antibody-mediated modulation was Treg-specific. IL-2C treatment resulted in an eight-fold elevation of peripheral CD4+CD25+Foxp3+ Tregs compared to mice administered with anti-CD25 mAb. In mice treated with PBS and anti-CD25 mAb, surgical stress response caused a significant increase of atherosclerotic plaque necrosis (PBS: p < 0.001; anti-CD25 mAb: p = 0.037). Preoperative Treg expansion abrogated perioperative necrotic core formation (p = 0.556) and significantly enhanced postoperative atherosclerotic plaque stability compared to PBS-treated mice (p = 0.036). Postoperative plaque volume (p = 0.960), stenosis (p = 0.693), lesional collagen (p = 0.258), as well as the relative macrophage (p = 0.625) and smooth muscle cell content (p = 0.178) remained largely unaffected by preoperative Treg levels. In atherosclerotic mice, therapeutic expansion of Tregs prior to major surgery mitigates rapid effects on perioperative stress-driven atherosclerotic plaque destabilization. Future studies will show, whether short-term interventions modulating perioperative inflammation qualify for prevention of cardiovascular events associated with major non-cardiac surgery.

Prospective evaluation of preoperative lung ultrasound for prediction of perioperative outcome and myocardial injury in adult patients undergoing vascular surgery (LUPPO study).

BACKGROUND: Myocardial injury after non-cardiac surgery (MINS) is a frequent perioperative event in vascular surgery, associated both with worse outcome and subsequent cardiovascular events. Current guidelines advocate troponin (hs-cTnT) and NT-proBNP measurements in selected patients before surgery, but accurate preoperative identification of patients at risk for MINS is an unmet clinical need. Focused lung ultrasound (LUS) might help to select patients at increased risk for MINS, because it can visualize B-line artifacts correlating to cardiopulmonary disease. Therefore, we investigated whether quantification of B-line artifacts improves perioperative risk predictive accuracy for MINS. METHODS: In this prospective single-center observational study, 136 consecutive open vascular surgery patients underwent conventional preoperative assessment expanded by lung ultrasound. Lung ultrasound B-lines were counted in each of 28 bilateral scan fields of the anterior and lateral chest. Improvement of risk predictive accuracy was quantified with area under receiver operating characteristic (ROC) curve analysis and net reclassification improvement (NRI). RESULTS: We included 118 patients into the final analysis. Twenty-three (19%) patients fulfilled the criteria for the primary endpoint MINS. Three or more bilateral positive B-line fields were calculated as the best ROC-derived cutoff associated with an increased incidence of MINS (odds ratio: 4.4; 95% confidence interval [CI]: 1.5 to 12.7; P=0.007). Adding LUS to hs-cTnT measurements improved risk predictive accuracy for MINS (NRI: 0.36, P=0.043). CONCLUSIONS: Lung ultrasound in combination with hs-cTnT showed a better test accuracy than hs-cTnT alone and might guide clinicians to identify vascular patients at increased risk for MINS.