Intraoperative haemodynamic optimisation using the Hypotension Prediction Index and its impact on tissular perfusion: a protocol for a randomised controlled trial.

INTRODUCTION: Intraoperative arterial hypotension is associated with poor postoperative outcomes. The Hypotension Prediction Index (HPI) developed using machine learning techniques, allows the prediction of arterial hypotension analysing the arterial pressure waveform. The use of this index may reduce the duration and severity of intraoperative hypotension in adults undergoing non-cardiac surgery. This study aims to determine whether a treatment protocol based on the prevention of arterial hypotension using the HPI algorithm reduces the duration and severity of intraoperative hypotension compared with the recommended goal-directed fluid therapy strategy and may improve tissue oxygenation and organ perfusion. METHODS AND ANALYSIS: We will conduct a multicentre, randomised, controlled trial (N=80) in high-risk surgical patients scheduled for elective major abdominal surgery. All participants will be randomly assigned to a control or intervention group. Haemodynamic management in the control group will be based on standard haemodynamic parameters. Haemodynamic management of patients in the intervention group will be based on functional haemodynamic parameters provided by the HemoSphere platform (Edwards Lifesciences), including dynamic arterial elastance, dP/dtmax and the HPI. Tissue oxygen saturation will be recorded non-invasively and continuously by using near-infrared spectroscopy technology. Biomarkers of acute kidney stress (cTIMP2 and IGFBP7) will be obtained before and after surgery. The primary outcome will be the intraoperative time-weighted average of a mean arterial pressure <65 mm Hg. ETHICS AND DISSEMINATION: Ethics committee approval was obtained from the Ethics Committee of Hospital Gregorio Marañón (Meeting of 27 July 2020, minutes 18/2020, Madrid, Spain). Findings will be widely disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT04301102.

Goal-Directed Fluid Therapy and Postoperative Outcomes in an Enhanced Recovery Program for Colorectal Surgery: A Propensity Score-Matched Multicenter Study.

INTRODUCTION: Goal-directed fluid therapy (GDFT) has increasingly been utilized in major surgery as a key component to ensure fluid optimization and adequate tissue perfusion, showing improvements in the rate of morbidity and mortality under conventional care. It is unclear if patients derive similar benefit as part of an enhanced recovery program (ERP). Our group sought to assess the association between GDFT and postoperative outcomes within an ERP for colorectal surgery. METHODS: A propensity score-matched analysis, based upon demographic characteristics, comorbidities, and ERP components, was utilized to assess the association between GDFT and outcomes in a multicenter prospective ERP for colorectal surgery cohort study. Outcomes included pulmonary edema, acute kidney injury (AKI), ileus, surgical site infection (SSI), and anastomotic dehiscence. The calipmatch module was used to match patients who received GDFT to non-GDFT in a 1-to-1 propensity score fashion. RESULTS: A total of 151 matched pairs were included in the analysis (n = 302, 23%). Both groups had comparable baseline demographics, as well as similar rates of compliance with enhanced recovery after surgery (ERAS) components. Goal-directed fluid therapy patients received significantly more colloid (237 ± 320 mL vs. 140 ± 245 mL, P < .01) than non-GDFT counterparts. Goal-directed fluid therapy was not associated with improved rates of postoperative AKI (odds ratios (OR) 1.00, 95% confidence intervals (CI) .39-2.59, P = 1.00), ileus (OR 1.40, 95% CI .82-2.41, P = .22), SSI (OR 1.06, 95% CI .54-2.08, P = .86), or length of hospital stay (LOS) (10.8 ± 8.9 vs. 11.1±13.2 days, P = .84). CONCLUSIONS: There was no associated between GDFT and major postoperative outcomes within an ERAS program for colorectal surgery. Additional large-scale or pragmatic randomized trials are necessary to determine whether GDFT has a role in ERP for colorectal surgery.

Risk factors for acute kidney injury in an enhanced recovery pathway for colorectal surgery.

PURPOSES: Enhanced recovery pathways (ERPs) have been disseminated worldwide to improve the perioperative patient outcomes while lowering direct healthcare costs. Recent evidence has revealed a potential association between ERPs for colorectal surgery and acute kidney injury (AKI). We, therefore, sought to identify the risk factors associated with postoperative AKI among patients in an ERP for colorectal surgery. METHODS: We analyzed the data resulting from a large multicenter, prospective cohort study of patients in an ERP for colorectal surgery. A multivariable analysis was performed to identify factors independently associated with postoperative AKI. The receiver operating characteristic (ROC) curves and contour representations were plotted for the diagnostic prediction analysis. RESULTS: Among those patients included in the analysis (n = 1652), the overall incidence of postoperative AKI was 7.7% (95% CI 6.5-9.1%). After adjustment, the independent risk factors for AKI included age > 60 (OR 1.03, 95% CI 1.01-1.05), male gender (OR 2.33, 95% CI 1.36-4.02), ASA III-IV (OR 2.43, 95% CI 1.39-4.26), CKD (OR 2.45, 95% CI 1.42-4.23), open surgical approach (OR 2.62, 95% CI 1.63-4.21) and serum albumin < 3.5 g/dL (OR 1.68, 95% CI 1.02-2.79). An ROC analysis revealed that the composite of albumin, creatinine and age was a strong predictor of postoperative AKI [area under the curve (AUC) 0.756; 95% CI 0.705-0.808]. CONCLUSION: Postoperative AKI is common in the setting of ERPs for colorectal surgery and it is associated with a poor clinical outcome. Of those characteristics associated with postoperative AKI, one modifiable factor is a low preoperative albumin level. Screening for malnourished patients or optimizing the nutritional status may be a useful preoperative intervention to prevent postoperative AKI and associated complications.