1037 Early Detection and Management of Preoperative Anaemia in An Elective Vascular Surgery Cohort

Introduction Iron deficiency anaemia is the most common cause of anaemia in the surgical population. Patients receiving transfusions during major surgery encounter more adverse outcomes compared to those that do not, indicating the early management of pre-operative anemia is likely to reduce major surgical patient morbidity and mortality. Previous studies have demonstrated that 33% of patients undergoing major vascular surgery operations are anaemic (haemaglobin, Hb, <130g/L). Aim We aim to reduce the proportion of anaemic patients undergoing major vascular surgery by 50%. Method A point-of-care HemoCue machine was used to measure Hb in patients who were referred for elective major surgery in 11 vascular clinics. Patients with Hb < 130g/L were prescribed a 1-month course of Ferrous Sulfate (200mg TDS), and a letter was sent to their GP requesting iron function tests. Post-intervention Hb levels were rechecked following the preoperative anaesthetics review. Results 11 patients were referred for major surgery, of which 4 were identified as anaemic (36%). The mean Hb concentration was 121.3g/L, which increased to 137.3g/L following oral iron therapy. The mean duration of follow up was 36 days (range 0-94 days). Conclusions The implementation of a HemoCue machine to identify and manage preoperative anaemia was successful in our pilot study. Further work should include full integration of our pathway into current vascular clinics without student support. This will enable evaluation of the impact of our intervention on a wider scale.

Protective ventilation measures improve outcomes during major vascular surgery

Background: In major endovascular and open vascular surgery cases, pulmonary complications remain persistently high and the most prevalent. Despite strong evidence from intensive care unit (ICU) practices demonstrating benefits of ventilation management with low tidal volume and high positive end expiratory pressure (PEEP), no consensus exists regarding protective ventilation use intraoperatively. Methods: A single institute, patient and surgeon blinded, prospective, randomized study design was used. Patients undergoing major vascular surgery (vascular surgery scheduled for >120 minutes and requiring general anesthesia) from 2015-2016 were randomized to pre-defined control (n = 14) or intervention (n =19) intraoperative ventilation arms. As described later, intervention consisted of a combination of low tidal volume, optimized positive end expiratory pressure (PEEP) and low intraoperative FiO2. Primary outcomes included all-cause mortality, myocardial infarction (MI) and reintubation within 7 post-operative days (POD). Secondary outcomes included atelectasis, pulmonary function measures, hospital length of stay and post-operative complications of re-intubation, pneumonia, sespsis, unplanned readmission or return to operating room, and/or mortality. Results: The intervention arm had significantly reduced post-operative atelectasis ((p <0.02) and increased post-operative SpO2 (p< 0.02). The intervention arm also had a significantly lower length of hospital stay (6.9±5.5 vs 3.3±1.8, p < 0.016). This was corroborated by a multivariate regression analysis that showed therapy was independently correlated with decreased length of stay (p<0.007). Conclusion: Our data indicate a combination of low tidal volumes, optimized PEEP and low FiO2 improves outcomes of patients undergoing major vascular surgery. Importantly, our study demonstrates that these study parameters for evaluation of intraoperative ventilation management are feasible in a busy academic center and a larger clinical trial is worthy. Protective intraoperative ventilation measures could have significant effects on vascular surgery outcomes.

Preoperative Levels of the Soluble Urokinase-Type Plasminogen Activator Receptor as Predictor for New Episodes of Atrial Fibrillation After Vascular Surgery

Introduction: The soluble urokinase-type plasminogen activator receptor (suPAR) in uPAR soluble form is produced when the uPAR is cleaved from the cell membrane during the inflammatory process. Postoperative atrial fibrillation (AF) is the most common perioperative cardiac arrhythmia. It is speculated that elevated suPAR has a role in the development of AF. The aim of our study was to investigate the predictive role of preoperative suPAR in the occurrence of AF during the first 6 months after major vascular surgery. Methods: We included 119 male and 63 female patients with an average age of 67.19 ± 6.02 years, without permanent/persistent AF. Basic predictive model (BASIC) included traditional risk factors for AF: age, gender, body mass index-BMI, smoking status, presence of arterial hypertension, diabetes mellitus and dyslipidemia. Results: Over the 6-month period, 19 (10.4%) patients had one new episode of atrial fibrillation and 2 patients (1.1%) had 2 episodes of paroxysmal atrial fibrillation. Paroxysms of AF were significantly more frequent in patients who had a resection of an abdominal aneurysm than in patients with other types of major vascular surgery. BASIC had good discriminatory ability in the prediction of AF paroxysms during the first 6 months after surgery (AUC = 0.715, 95%CI 0.590-0.840). Adding suPAR to the basic model significantly improved the discriminative ability of the predictive model for AF episodes (ΔAUC = 0.238, p < 0.001). The predictive performance of the model BASIC+CRP+suPAR, measured using AUC, NRI and IDI statistics, was very similar to the model BASIC+suPAR. Conclusion: AF is a common complication in surgical patients with high mortality and morbidity. suPAR could improve the ability of traditional risk factors to predict its occurrence up to 6 months after major vascular surgery.