November 2016


Title: The incidence and importance of anaemia in patients undergoing cardiac surgery in the UK – the first Association of Cardiothoracic Anaesthetists national audit.


DOI: 10.1111/anae.13423

Published: 18th March 2016

Authors: Klein AA, Collier TJ, Brar MS, Evans C, Fletcher SN, Richards T, and on behalf of the Association of Cardiothoracic Anaesthetists (ACTA)

Study description and main objective:

The Association of Cardiothoracic Anaesthetists in UK carried out a national audit on anaemia and transfusion, and analysed data from 19,033 patients operated on in 12 cardiac surgical centres between 2010 and 2012; 5895 (31%) of them had pre-operative anaemia.

The association between anaemia and other pre-operative variables (including patients' characteristics, comorbid disease, pre-operative creatinine level and logistic EuroSCORE) was assessed. Additionally, the association between anaemia and the outcomes of transfusion at any point in the peri-operative period, ICU and hospital length of stay, and 30-day mortality were analysed using multivariable logistic regression model.

The research question is to assess the prevalence of pre-operative anaemia among UK cardiac surgery patients and evaluate the effect of anaemia on outcomes in UK cardiac surgery centres.

Main findings:

•    Centre-specific prevalence of anaemia varied from 23% to 45%.
•    Anaemia was associated with older patients, diabetes and surgical risk (EuroSCORE). Nevertheless, controlling for these factors, regional     variation  remained an independent effect (p < 0.001).
•    Multivariable analysis demonstrated an independent association of anaemia with (1) transfusion (odds ratio (95% confidence interval (CI) 2.75 (2.55–2.95)), (2) mortality (95% CI 1.42 (1.18–1.71),) and (3) hospital stay (geometric mean ratio (95% CI) 1.15 (1.13–1.17).
•    Haemoglobin concentration per se was also independently associated with worse outcomes.

Clinical impact and questions:

1)    Identification of pre-operative anaemia is one of the important actions to improve patient’s outcomes after cardiac surgery.
2)    There is a strong association between pre-operative anaemia and mortality and morbidity.
3)    In your practice, what is the haemoglobin concentration triggering for transfusion before cardiac surgery?
4)    Do you have a well-structured service at your centre to actively manage patients with anaemia before cardiac surgery? If yes, can you share your experience with the EACTA community?