The management of peri-operative anaemia in patients undergoing major abdominal surgery in Australia and New Zealand: a prospective cohort study

Objectives: To assess the prevalence and management of anaemia in patients undergoing major abdominal surgery, and the influence of guideline adherence on patient outcomes. 

Design: Prospective observational cohort study. 

Setting: 56 hospitals in Australia and New Zealand. 

Participants: People aged 18 years or more who underwent major abdominal surgery during two 2-week periods in July 2021. 

Main outcome measures: Proportions of patients managed according to Australian National Blood Authority patient blood management guidelines. Secondary outcomes: anaemia prevalence, post-operative complications, length of hospital stay, re-admission within 30 days of discharge. 

Results: Data were available for 2730 eligible patients (mean age, 56.7 years; SD, 17.3 years), including 1558 women (57.1%). Haemoglobin levels prior to surgery were documented for 2461 of 2727 patients (90.2%), 689 of whom had anaemia (28.0%). Pre-operative anaemia assessment and management were associated with lower likelihood of intra-operative (adjusted odds ratio [aOR], 0.33; 95% CI, 0.19–0.57) and post-operative blood transfusion (aOR, 0.36; 95% CI, 0.25–0.53), and of post-operative complications (aOR, 0.79; 95% CI, 0.63–0.99). Tranexamic acid was administered during 128 of 2728 procedures (4.7%); a restrictive transfusion strategy was followed for 96 of the 167 patients who received post-operative blood transfusions (58%). Post-operative anaemia was identified in 1227 of 2069 patients (59.3%) in whom haemoglobin was assessed prior to discharge. The proportion of people re-admitted to hospital within 30 days was larger for patients with anaemia at discharge (169 of 1207 patients followed up, 14.0% v 61 of 825, 7.4%). Haemoglobin assessments were recorded by 30 days after discharge for only 288 patients with post-operative anaemia (24.3%). 

Conclusions: The management of peri-operative anaemia differs between hospitals in Australia and New Zealand, with consequences for patient outcomes. Patients are often discharged after surgery with anaemia, which is therefore a potential therapeutic target. Trial registration: Australian New Zealand Clinical Trials Registry, ACTRN12621001517864 (retrospective).