Posterior pericardiotomy and the prevention of post-operative atrial fibrillation and cardiac tamponade in isolated coronary artery bypass grafting - A retrospective analysis.

BACKGROUND: Post-Operative Atrial Fibrillation (POAF) is the most frequent complication of cardiac surgery and is associated with reduced survival, increased rates of cognitive changes and cerebrovascular accidents, heart failure, renal dysfunction, infection, length of stay and hospital costs. Cardiac tamponade although less common, carries high morbidity and mortality. Shed mediastinal blood in the pericardial space is a major source of intrapericardial oxidative stress and inflammation that triggers POAF. The utilisation of a posterior pericardiotomy (PP) aims to shunt blood from pericardium into the pleural space and have a role in the prevention of POAF as well as cardiac tamponade. METHODS: 2168 patients had undergone isolated Coronary Artery Bypass Grafting at Royal Hobart Hospital from 2008 to 2022. They were divided into PP group vs. control group. Patient baseline demographics, intraoperative data and post-operative outcomes were reviewed retrospectively. RESULTS: Total incidence of new POAF and cardiac tamponade was 24% and 0.74% respectively. Primary outcome of both the incidence of POAF (20.2% vs. 26.3%, p < 0.05) and Cardiac Tamponade (0% vs. 1.1%, p < 0.05) were less in the pericardiotomy group. A subgroup analysis of patients with recent myocardial infarction showed reduced incidence of POAF in the PP group (p < 0.05). Increasing age, Body Mass Index, poor left ventricular ejection fraction (EF < 30%) and return to theatre were independent predictors of developing POAF. There were similar rates of return to theatre for bleeding however, no cases of tamponade in the pericardiotomy group. There were no complications attributable to left posterior pericardiotomy and the time added to the duration of surgery was minimal. CONCLUSION: Posterior pericardiotomy is associated with a significant reduction in the incidence of POAF and cardiac tamponade which is safe and efficient.

Acute kidney injury, stroke and death after cardiopulmonary bypass surgery: the role of perfusion flow and pressure.

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.

Developing a benchmarking process in perfusion: a report of the Perfusion Downunder Collaboration.

Improving and understanding clinical practice is an appropriate goal for the perfusion community. The Perfusion Downunder Collaboration has established a multi-center perfusion focused database aimed at achieving these goals through the development of quantitative quality indicators for clinical improvement through benchmarking. Data were collected using the Perfusion Downunder Collaboration database from procedures performed in eight Australian and New Zealand cardiac centers between March 2007 and February 2011. At the Perfusion Downunder Meeting in 2010, it was agreed by consensus, to report quality indicators (QI) for glucose level, arterial outlet temperature, and pCOz management during cardiopulmonary bypass. The values chosen for each QI were: blood glucose > or =4 mmol/L and < or =10 mmol/L; arterial outlet temperature < or = 37 degrees C; and arterial blood gas pCO2 > or =35 and < or =45 mmHg. The QI data were used to derive benchmarks using the Achievable Benchmark of Care (ABC) methodology to identify the incidence of QIs at the best performing centers. Five thousand four hundred and sixty-five procedures were evaluated to derive QI and benchmark data. The incidence of the blood glucose QI ranged from 37-96% of procedures, with a benchmark value of 90%. The arterial outlet temperature QI occurred in 16-98% of procedures with the benchmark of 94%; while the arterial pCO2 QI occurred in 21-91%, with the benchmark value of 80%. We have derived QIs and benchmark calculations for the management of several key aspects of cardiopulmonary bypass to provide a platform for improving the quality of perfusion practice.