Impact of gender parity on preoperative anaemia prevalence and Patient Blood Management practice

Abstract

Background: Anaemia is a common finding in the preoperative setting, affecting around one-third of patients for whom major surgery is programmed. Moreover, preoperative anaemia has been shown to worsen patient outcome and increase length of hospital stay and costs. In the field of preoperative anaemia correction, a recent Consensus statement suggested reviewing the classic World Health Organization (WHO) criteria in adults by aligning the haemoglobin cut-off to 13 g/dL for both genders. The aim of our study was to assess the differences in terms of prevalence, transfusion rate, transfusion trigger, and blood losses according to gender in a mixed population of surgical patients.

Material and methods: We reviewed data of 610 consecutive patients undergoing elective major surgery at a tertiary care hospital during a 9-month period. Transfusion rate and transfusion triggers were recorded, analysed and stratified by haemoglobin class, with a particular focus on the 12.0-12.9 g/dL range.

Results: Since the anaemia threshold was redefined at 13 g/dL for both genders, its prevalence rose from 26.4 to 39.5% (161/610 vs 241/610; p<0.001) in the overall population and from 22.7 to 49.3% (68/300 vs 148/300; p<0.001) in women. Eighty women (26.7%) fell in the haemoglobin 12.0-12.9 g/dL range, and this category was the most represented among transfused women (34.0%). There was no statistical difference in transfusion triggers or overall transfusion rate between genders. Subjects of both genders were transfused at the same haemoglobin level (8.1 g/dL), but women reached the transfusion trigger after less red cell mass loss than men, i.e. 377 mL (249-472 mL) vs 528 mL (356-717 mL), respectively (p<0.001).

Discussion: Treatment of pre-surgical anaemia is one of the core principles of Patient Blood Management. Aligning the haemoglobin threshold between genders in the management of pre-surgical anaemia may result in a lower transfusion rate, but in an increased workload for medical staff in the preoperative phase.

Figure 1. Prevalence of preoperative anaemia

WHO: World Health Organization anaemia criteria (anaemia thresholds: 13 g/dL for males; 12 g/dL for women). PBM: Patient Blood Management guidelines; Hb: haemoglobin; PBM-Hb: anaemia classification according to PBM (anaemia threshold: Hb<13.0 g/dL for both sexes). Numbers at top of each column represent absolute numbers of patients.