The effect of postoperative intravenous iron in anaemic, older cardiac surgery patients on disability-free survival (AGE ANEMIA study): study protocol for a multi-centre, double-blind, randomized, placebo-controlled trial.

BACKGROUND: Postoperative anaemia is common in older cardiac surgery patients and often caused by iron deficiency. Anaemia may negatively affect recovery after cardiac surgery. This study aims to determine the efficacy of treatment of postoperative iron deficiency anaemia (IDA) with intravenous iron (IVI) on disability 90 days after cardiac surgery in older patients. METHODS: This is a randomized placebo-controlled double-blind multi-centre trial. In total, 310 patients aged ≥ 70 years with moderate IDA on postoperative day 1 (haemoglobin 85-110 g/L and ferritin concentration < 100 µg/L or iron saturation < 20%) after uncomplicated elective cardiac surgery (aortic valve repair or coronary artery bypass graft surgery) will be included. Patients will be randomly allocated to receive either IVI (ferric derisomaltose) or placebo (sodium chloride 0.9%) on postoperative day 1 in a 1:1 ratio, stratified by centre and type of cardiac surgery. The primary outcome is disability measured by the 12-item World Health Organization Disability Assessment score 2.0 after 90 days. Secondary outcome measures are the number of postoperative red blood cell (RBC) transfusions, change in reticulocyte haemoglobin content (pg) from randomization to hospital discharge, Hb levels at discharge, hospital complications, dyspnoea (assessed with the Rose Dyspnoea Scale) and health-related quality of life (HRQL) (assessed with The Older Persons and Informal Caregivers-Short Form (TOPICS-SF) questionnaire) after 90 days and days alive and out of hospital after 90 days. Lastly, the functional outcomes (e.g. steep ramp or 6-min walk test) and Hb level after 90 days will be assessed as an exploratory endpoint. DISCUSSION: The results of this study will demonstrate whether early treatment of postoperative IDA with IVI improves disability at 90 days in older cardiac surgery patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT04913649. Registered on June 4, 2021.

Quality of recovery after day care surgery with app-controlled remote monitoring: study protocol for a randomized controlled trial.

BACKGROUND: The majority of surgical interventions are performed in day care and patients are discharged after the first critical postoperative period. At home, patients have limited options to contact healthcare providers in the hospital in case of severe pain and nausea. A smartphone application for patients to self-record pain and nausea when at home after day care surgery might improve patient's recovery. Currently patient experiences with smartphone applications are promising; however, we do not know whether remote monitoring with such an application also improves the patient's recovery. This study aims to evaluate the experienced quality of recovery after day care surgery between patients provided with the smartphone application for remote monitoring and patients receiving standard care without remote monitoring. METHODS: This non-blinded randomized controlled trial with mixed methods design will include 310 adult patients scheduled for day care surgery. The intervention group receives the smartphone application with text message function for remote monitoring that enables patients to record pain and nausea. An anaesthesia professional trained in empathetic communication, who will contact the patient in case of severe pain or nausea, performs daily monitoring. The control group receives standard care, with post-discharge verbal and paper instructions. The main study endpoint is the difference in perceived quality of recovery, measured with the QoR-15 questionnaire on the 7th day after day care surgery. Secondary endpoints are the overall score on the Quality of Recovery-15 at day 1, 4 and 7-post discharge, the perceived quality of hospital aftercare and experienced psychological effects of remote monitoring during postoperative recovery from day care surgery. DISCUSSION: This study will investigate if facilitating patients and healthcare professionals with a tool for accessible and empathetic communication might lead to an improved quality of the postoperative recovery period. TRIAL REGISTRATION: The 'Quality of recovery after day care surgery with app-controlled remote monitoring: a randomized controlled trial' is approved and registered on 23 February 2022 by Research Ethics Committees United with registration number R21.076/NL78144.100.21. The protocol NL78144.100.21, 'Quality of recovery after day care surgery with app-controlled remote monitoring: a randomized controlled trial', is registered at the ClinicalTrials.gov public website (registration date 16 February 2022; NCT05244772).

Performance and usability of pre-operative prediction models for 30-day peri-operative mortality risk: a systematic review.

Estimating pre-operative mortality risk may inform clinical decision-making for peri-operative care. However, pre-operative mortality risk prediction models are rarely implemented in routine clinical practice. High predictive accuracy and clinical usability are essential for acceptance and clinical implementation. In this systematic review, we identified and appraised prediction models for 30-day postoperative mortality in non-cardiac surgical cohorts. PubMed and Embase were searched up to December 2022 for studies investigating pre-operative prediction models for 30-day mortality. We assessed predictive performance in terms of discrimination and calibration. Risk of bias was evaluated using a tool to assess the risk of bias and applicability of prediction model studies. To further inform potential adoption, we also assessed clinical usability for selected models. In all, 15 studies evaluating 10 prediction models were included. Discrimination ranged from a c-statistic of 0.82 (MySurgeryRisk) to 0.96 (extreme gradient boosting machine learning model). Calibration was reported in only six studies. Model performance was highest for the surgical outcome risk tool (SORT) and its external validations. Clinical usability was highest for the surgical risk pre-operative assessment system. The SORT and risk quantification index also scored high on clinical usability. We found unclear or high risk of bias in the development of all models. The SORT showed the best combination of predictive performance and clinical usability and has been externally validated in several heterogeneous cohorts. To improve clinical uptake, full integration of reliable models with sufficient face validity within the electronic health record is imperative.

Postoperative myocardial injury and platelet reactivity in patients undergoing vascular surgery: The platelet reactivity and postoperative myocardial injury after major vascular surgery (PROMISE) study.

BACKGROUND: Postoperative myocardial injury (PMI) after major vascular surgery, detected by elevated cardiac troponin (cTn), has been associated with morbidity and mortality. It is unclear whether the pathophysiology of PMI is determined by increased platelet activity. OBJECTIVE: To examine the relationship between platelet activation (P-selectin expression) and PMI in patients undergoing elective open abdominal aortic surgery. METHODS: This prospective, single-centre, observational, cohort study included 33 patients undergoing elective open abdominal aortic surgery between March 2018 and April 2021. Patients were routinely treated with aspirin. Unstimulated platelet activation was measured by platelet bound P-selectin expression (range 0-100 %). Explorative coagulation measurements were: stimulated platelet aggregation measured with the VerifyNow® assay (aspirin cartridge), with the Multiplate® analyzer (ASPI, ADP and TRAP) and stimulated coagulation status evaluated by the TEG® Hemostasis Analyzer System (global hemostasis cartridge). The primary outcome was cTn release assessed by the fifth generation high-sensitive cTn assay. Multivariable generalized linear mixed models were used to evaluate the association between platelet function and cTn concentrations over time. RESULTS: Ten patients (30.3 %) developed PMI. Increased P-selectin expression directly after surgery was associated with the cTn concentrations over 48 h (ß = 1.39 (1.1-1.75), P = 0.0064). No association was found between P-selectin measured later after surgery (at 24 h or 48 h) and cTn concentrations. Furthermore, there was no association between the explorative coagulation parameters and cTn release. CONCLUSION: Platelet reactivity, assessed by P-selectin expression measured directly after surgery is associated with PMI, assessed by elevated cTn concentrations in the early postoperative period in patients undergoing elective open abdominal aortic surgery.

The effect of remote ischaemic preconditioning on postoperative cardiac and inflammatory biomarkers in pancreatic surgery: a randomized controlled trial.

BACKGROUND: Cardiac and inflammatory biomarkers have been associated with adverse outcome after major abdominal surgery. This study investigated the effect of remote ischaemic preconditioning (RIPC) on perioperative concentrations of high-sensitive cardiac troponin (hs-cTn) T and interleukin (IL) 6. METHODS: Adult patients scheduled for elective pancreatic surgery between March 2017 and February 2019 were randomized to either three cycles of upper-limb ischaemia and reperfusion (each 5 min) or a sham procedure before surgery. The primary endpoint was the maximum postoperative hs-cTnT concentration within 48 h after surgery. Secondary endpoints were postoperative myocardial injury (PMI), defined as an absolute increase of hs-cTnT of at least 14 ng/l above baseline concentration, maximum concentration of IL-6 within 48 h after surgery and postoperative complications within 30 days of surgery. RESULTS: Of 99 eligible patients, 46 underwent RIPC and 46 a sham procedure. RIPC did not reduce the maximum hs-cTnT concentration after surgery (12.6 ng/l RIPC, 16.6 ng/l controls, P = 0.225), nor did it lessen the incidence of PMI (15/45 RIPC, 18/45 controls, P = 0.375). The maximum postoperative IL-6 concentration was 265 pg/ml after RIPC versus 385 pg/ml in controls (P = 0.108). Postoperative complications occurred in 23 RIPC and 24 control patients respectively. CONCLUSIONS: Remote ischaemic preconditioning did not reduce the maximum postoperative hs-cTnT concentration. Postoperative myocardial injury, IL-6 concentrations and postoperative complications were similar between RIPC patients and controls. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT03460938.

Different methods of modelling intraoperative hypotension and their association with postoperative complications in patients undergoing non-cardiac surgery.

BACKGROUND: Associations between intraoperative hypotension (IOH) and postoperative complications have been reported. We examined whether using different methods to model IOH affected the association with postoperative myocardial injury (POMI) and acute kidney injury (AKI). METHODS: This two-centre cohort study included 10 432 patients aged ≥50 yr undergoing non-cardiac surgery. Twelve different methods to statistically model IOH [representing presence, depth, duration, and area under the threshold (AUT)] were applied to examine the association with POMI and AKI using logistic regression analysis. To define IOH, eight predefined thresholds were chosen. RESULTS: The incidences of POMI and AKI were 14.9% and 14.8%, respectively. Different methods to model IOH yielded effect estimates differing in size and statistical significance. Methods with the highest odds were absolute maximum decrease in blood pressure (BP) and mean episode AUT, odds ratio (OR) 1.43 [99% confidence interval (CI): 1.15-1.77] and OR 1.69 (99% CI: 0.99-2.88), respectively, for the absolute mean arterial pressure 50 mm Hg threshold. After standardisation, the highest standardised ORs were obtained for depth-related methods, OR 1.12 (99% CI: 1.05-1.20) for absolute and relative maximum decrease in BP. No single method always yielded the highest effect estimate in every setting. However, methods with the highest effect estimates remained consistent across different BP types, thresholds, outcomes, and centres. CONCLUSIONS: In studies on IOH, both the threshold to define hypotension and the method chosen to model IOH affects the association of IOH with outcome. This makes different studies on IOH less comparable and hampers clinical application of reported results.