Page 58 - ANZCP Gazette May 2023

of calculating DAH30 for cardiac surgical patients in a single Australian centre, with a view to proposing its calculation at ANZCPR registry sites across Australasia.
The ANZCPR registry routinely collects date of procedure, date of discharge and, where relevant, date of death. To calculate DAH30, we prospectively collected readmission dates from 01/09/2019 to 31/05/2022 (approximately 1280 patients) from the hospital's eMR(HREC/15/SAC/341). This added less than two minutes per patient to our data collection workflow. DAH30 was calculated using a Visual Basic for Applications program in Microsoft Access.
DAH30 can be calculated easily and reliably at a single ANZCPR cardiac surgical centre. We conclude that it is feasible to calculate at other sites within the ANZCPR registry.
REFERENCES:
Myles PS, Shulman MA, Heritier S, et al. Validation of days at home as an outcome measure after surgery: a prospective cohort study in Australia BMJ Open 2017;7:e015828.
THE EFFECT OF EMBOLI EXPOSURE ON CEREBRAL AUTOREGULATION IN CARDIAC SURGERY REQUIRING CARDIOPULMONARY BYPASS
Ghazwan Jabur, Alan Merry, Alistair Mcgeorge, Alana Cavadino, Joseph Donnelly AND Simon Mitchell
Department of Clinical Perfusion, Auckland City Hospital, Auckland, Aotearoa New Zealand
PURPOSE: The risk of stroke in cardiac surgery has been associated with cerebral autoregulation impairment. We hypothesize that higher embolic exposure in open- chamber cardiac surgery patients might promote cerebral dysautoregulation.
METHODOLOGY: Bilateral middle cerebral artery flow velocities and embolic counts were recorded using transcranial Doppler in forty patients undergoing open- or closed-chamber surgery. An average mean velocity index was calculated to assess cerebral autoregulation over 30 minutes before and after the removal of the aortic cross-clamp.
RESULTS:Themajorityofemboli(median(interquartile range)) were detected after the release of the aortic cross-clamp (open-chamber: 1631 (606, 2296)), (closed- chamber: 229 (142, 384)), with a focus on the right hemisphere (open-chamber: 826 (371, 1622)), (closed- chamber 181 (66, 276)). No significant effect of group (0.08, 95% CI: -0.04, 0.21; P = 0.19) or side (0.01, 95% CI: -0.03, 0.05; P = 0.74) was observed in the change
mean velocity index using a linear mixed model analysis. There was an overall group-side interaction (P = 0.001), represented by a larger increase in mean velocity index in the right cerebral hemisphere in the open-chamber compared to closed-chamber group (mean difference: 0.15, 95 % CI: 0.02, 0.27; P = 0.03).
CONCLUSION: There was no overall difference between the groups in the change in mean velocity index before and after removing the aortic cross-clamp. However, this change was significantly greater in the right cerebral hemisphere in the open-chamber group where most of the emboli were detected, suggesting a possible association between exposure to emboli and cerebral dysautoregulation.
TETRALOGY OF FALLOT: 40 YEARS OF TRANSATRIAL REPAIR, HOW THINGS HAVE CHANGED
Clarke Thuys
The Royal Children's Hospital, Victoria
PURPOSE: The aim of this audit was to track changes in patient and bypass parameters from 1982 when the transatrial approach was adopted as the sole operative technique for Tetralogy of Fallot at the Royal Children’s Hospital.
METHODOLOGY: Data from bypass records and patient histories; where available, were collated on a year by year basis. Demographic and bypass data were analysed for changes in patient age, size, bypass time, cross clamp time, circulatory arrest time, prime volume, length of stay and rate of reoperation. Data from the Departments paper “Intersurgeon variability in long- term outcomes after transatrial repair in tetralogy of Fallot: 25 years’ experience with 675 patients” JTCVS 2014. 147(3): 880-888.
RESULTS: There have been changes in all measured parameters over the forty years. While patients have trended to being younger and smaller, bypass and cross clamp times have increased. Circulatory arrest has disappeared altogether. Length of Stay has increased while the rate of Reoperation has fallen. There is some variation in the type of re-operation although this could be due to differences in the information available.
CONCLUSION: Over 40 years the outlook for patients has improved. Changes in parameters measured, apart from the patient demographics, are due to a number of factors. The important changes are the elimination of circulatory arrest, minimisation of use of donor blood, and the reduction in reintervention.
55 MAY 2023 | www.anzcp.org