Objective

Pre-operative anaemia (PA) is associated with red blood cell (RBC) transfusion need and increased mortality. However, its relationship with total post-operative morbidity burden has not previously been assessed. Thus, we sought to determine the association between pre-operative anaemia, RBC transfusion need and post-operative morbidity using the Cardiac Post-Operative Morbidity Score (C-POMS).

Methods

442 cardiac surgery patients were prospectively studied. Presence of anaemia (females, Hb<12g/dL; males <13 g/dL) and RBC transfusion given pre- or intra-operatively, were documented. Morbidity was assessed by C-POMS, scored by the presence or absence of 13 individual domains and total morbidity burden (TMB; total summative score) on each post-operative day (3, 5, 8 & 15 (D3-D15)). Groups were compared by Mann-Whitney-U tests (TMB) and logistic regression (transfusion, domains).

Results

PA (n=139, 31.5%), was associated with renal (p<0.001) & ambulation (p=0.0026) morbidity. PA patients had higher TMB on D3 & D5 than non-PA patients (5 vs 3 and 3 vs 2, both p<0.0001). They were three times more likely to be transfused than non-PA patients (OR 3.08, 95%CI 1.88-5.06, p<0.001; 14.1% vs. 33.6%). Transfusion was associated with pulmonary, renal, GI, neurological, endocrine and ambulation morbidities (p 0.026 to <0.001). Both PA and RBC need were independently associated with TMB.

Conclusion

PA and RBC transfusion use are both associated with significant morbidity after cardiac surgery. Whether such associations are due to the anaemia, the processes driving that anaemia, or to adverse effects of transfusion itself remain to be explored. Nevertheless, implementing strategies to reduce pre-operative anaemia and RBC transfusion may improve patient well-being and recovery, organisational productivity and health care provider financial efficiency.