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Currently 30-day mortality is commonly used as a quality indicator for cardiac surgery; however, prediction models have not included the role of cardiopulmonary bypass (CPB). We hypothesized that reproducing currently utilised prediction model methods of 30-day mortality using the Australian and New Zealand Collaborative Perfusion Registry (ANZCPR) would identify relevant CPB predictors. Nine centers in Australia and New Zealand collected data using the ANZCPR between 2011–2020. CPB parameter selection was determined by evaluating association with 30-day mortality. Data were divided into model creation (n = 15,073) and validation sets (n = 15,072). Bootstrap sampling and automated variable selection methods were used to develop candidate models. The final model was selected using prediction mean square error and Bayesian Information Criteria. The average receiver operating characteristic (ROC), p -value for Hosmer—Lemeshow chi-squared test and MSE were obtained from multifold validation. In total, 30,145 patients were included, of which 735 (2.4%) died within 30 day of surgery. The area under the ROC curve for the model including CPB parameters was significantly greater than preoperative risk factors only (0.829 vs 0.783, p < 0.001). CPB parameters included in the predictive model were CPB time, red blood cell transfusion, mean arterial pressure <50 mmHg, minimum oxygen delivery, cardiac index <1.6 L/min/m2. CPB parameters improve the prediction of 30-day mortality. Randomised trials designed to evaluate modifiable CPB parameters will determine their impact on mortality. [ABSTRACT FROM AUTHOR]

Background: del Nido cardioplegia has been adopted for use in adult cardiac surgery, despite a lack of robust randomised evidence supporting equivalence or superiority to conventional hyperkalaemic blood cardioplegia. We investigated the clinical surrogates of myocardial protection, and performed an extensive analysis of post‐operative high‐sensitivity Troponin T (hs‐TnT) values in a general adult cardiac surgery population receiving del Nido, in comparison to a historical hyperkalaemic blood cohort. Method: 171 consecutive patients of a single surgeon from between November 2018 and June 2020 received del Nido, and were compared to a historical cohort of 326 patients between January 2016 and November 2018 who received hyperkalaemic blood cardioplegia. Clinical markers of myocardial protection were compared, as were hs‐TnT values at 6, 12, 24, and 72‐h post‐operatively. Equivalence between groups was determined using the two one‐sided tests procedure. Results: There was no difference between the groups in the incidence of post‐operative low cardiac output state, inotropic support, or myocardial infarction. Del Nido patients had less defibrillation requirement, and more spontaneous resumption of normal sinus rhythm. High‐sensitivity Troponin T values were similar at all time‐points including in a coronary artery bypass graft subgroup, and in those patients with elevated pre‐operative hs‐TnT. Conclusion: In a broad cohort of adult cardiac surgery patients, including those undergoing coronary artery bypass surgery and those with recent myocardial infarction, del Nido provides equivalent myocardial protection and clinical outcomes when compared to hyperkalemic blood cardioplegia. Post‐operative high‐sensitivity Troponin T values were also equivalent between the groups. [ABSTRACT FROM AUTHOR]

Introduction: Acute kidney injury after cardiopulmonary bypass surgery is associated with morbidity and mortality. This study aims to evaluate the role of low perfusion flow and pressure in the development of cardiopulmonary bypass–associated acute kidney injury, stroke and death, using multicentre registry data. Methods: We identified patients from the Australian and New Zealand Collaborative Perfusion Registry who underwent coronary artery bypass grafting and/or valvular surgery between 2008 and 2018. Primary predictor variables were the length of time the perfusion flow was <1.6 L/min/m2 and the length of time perfusion pressure was < 50mmHg. The primary outcome was new postoperative acute kidney injury defined by the risk-injury-failure-loss-end stage criteria. Secondary outcomes were stroke and in-hospital death. The influence of perfusion flow and pressure during cardiopulmonary bypass on the primary and secondary outcomes was estimated using separate multivariate models. Results: A total of 16,356 patients were included. The mean age was 66 years and 75% were male. Acute kidney injury was observed in 1,844 patients (11%), stroke in 204 (1.3%) and in-hospital death in 286 (1.8%). Neither the duration of the time spent for perfusion flow (<1.6 L/minute/m2) nor the duration of the time spent for perfusion pressure (<50 mmHg) was associated with postoperative acute kidney injury, stroke or death in adjusted models. Conclusions: Neither low perfusion pressure nor low perfusion flow during cardiopulmonary bypass were predictive of postoperative acute kidney injury, stroke or death. [ABSTRACT FROM AUTHOR]

The desire to optimize techniques and interventions that comprise clinical practice will inevitably involve the implementation of change in the process of care. To confirm the intended benefits of instituting clinical change, the process should be undertaken in a scientific manner. Although implementing changes in perfusion practice is limited by the availability of evidence based practice guidelines, we have the opportunity to audit our current practice according to institutional guidelines using quality improvement methods. Current electronic data collection technology is a useful tool available to facilitate the reporting of both clinical and process outcome improvements. The model of clinical effectiveness can be used as a systematic approach to introducing change in clinical practice, which involves reviewing the literature, acquiring appropriate skills and resources, auditing the change, and implementing continuous quality improvement to standardize the process. Finally, reporting the findings allows dissemination of the knowledge that can be generalized. Reporting change strengthens our efforts in clinical effectiveness, highlights the importance of perfusion practice, and increases the influence of the profession.

Neurological deficits such as stroke and subtle psychological, cognitive, and behavioral changes are known risks associated with cardiac surgery. These altered neurologic outcomes have a significant impact on patients and their quality of life postoperatively. Perioperative events, such as cerebral embolism and decrease in cerebral oxygenation and hypoperfusion have been identified as factors causal in producing adverse neurologic outcomes. More importantly, a number of mechanisms related to operative techniques have been found to cause these adverse events. Identifying practices associated with adverse outcomes and implementing practice changes may benefit clinical outcomes for cardiac surgery patients. Standardizing techniques among clinicians will also achieve continuous quality improvement in the process of care. Optimal intra-operative management systems contribute significantly to ensuring good patient outcomes (i.e., avoiding neurological injury in patients which is an important cause of post-operative morbidity and mortality). Groom and colleagues (2004) have developed a system to obtain a thorough understanding and redesign of the process of care associated with cardiac surgery. They have developed a system that simultaneously measures some embolic activity, cerebral oxygen saturation, and physiologic parameters, as well as uses a video recording device during cardiac surgery. To date, the evaluation of this methodology in a rigorous, prospective manner has not been reported. Our aim is to conduct a randomised clinical trial to evaluate the influence of continuous quality improvement in cardiac surgery using biofeedback (i.e., real time information on physiologic functioning from an integrated monitoring system) to reduce the incidence of potentially adverse events during surgery. By achieving the outcomes of this project, we plan to be able to not only introduce change in our own practice, but provide a framework for other units to introduce change.