Associations between preoperative anaemia, transfusion and outcomes in older hip fracture patients

Abstract

Background: Anaemia in hip fracture patients has been associated with increased risk of allogenic blood transfusion (ABT), poorer functional outcomes and increased mortality. While incidence of anaemia after hip fracture surgery has been reported to be as high as 86%, few studies have reported the prevalence of anaemia on admission or it's progression prior to surgery in the older hip fracture population. Aims: To measure the prevalence of anaemia on admission in older persons who sustain a hip fracture, identify if anaemia progresses prior to surgery and report associations with ABT, length of stay (LOS) and in hospital mortality (IHM). Methods: A retrospective, observational study was undertaken in a regional hospital. All patients aged 60 and over, admitted with a primary hip fracture resulting from a simple fall, in the 12 months of 2014 were included. The world health organization (WHO) definition of anaemia was used. Pathology databases and clinical records were reviewed to collect the following data for the period between admission and surgery: demographics (age and sex), fracture type (intracapsular or extracapsular), use of anticoagulant or antiplatelet medication (excluding aspirin), pre-surgery serial haemaglobin (Hb) levels (as available), LOS, packed red blood cells (PBRC) transfusions during the admission, and IHM. Repeated measures ANOVA's were used to quantify the progression of anaemia prior to surgery, and Chi square and Fisher's exact tests were used to report associations with outcome variables. Results: A total of 261 patients were identified. The median (IQR) age was 84 years (11). There were twice as many females (n = 186) as males (n = 75) and just over half the sample had extracapsular fractures (n = 141). Anaemia was present on admission in 45% (n = 117),with mean Hb (SD) 122.9 g/L (16.5). The highest incidence of anaemia occurred in males 51% (n = 38), extracapsular fractures 53.8% (n = 77) and those aged over 80 years 52% (n = 95). Progression of anaemia prior to surgery was significant in all groups (P < 0.05). Mean time from admission to surgery was 1.23 days. The mean Hb decrease prior to surgery was 13 g/L with the greatest reduction (19 g/L) seen in extracapsular fractures. Pre-surgery reduction in Hb was recorded in 82.9% of patients between admission and day 1, and in 69.8% between day 1 and day 2. Overall the postoperative transfusion rate was 29.1% with the highest rate in extracapsular fractures (43.6%). There was significant association between anaemia on admission and PRBC transfusion (P < 0.05) and hospital mortality (P < 0.05). There was no association with the use of antiplatelet or anticoagulant medication, nor LOS. Summary/Conclusions: The findings demonstrate that pre surgical anaemia in older hip fracture patients is associated with a PRBC transfusion and increased hospital mortality. Importantly, it also identified that patients continue to bleed after admission, leading to the development of or worsening anaemia. Thus identification anaemia in the pre surgical period provides an opportunity for treatment to avoid transfusions and improve patient outcomes.L616917364 <br />