An Investigation Into the Risk Factors for Transfusion Need After Neck of Femur Fracture Surgery.

BACKGROUND

A common surgical procedure in the elderly is the operation on neck of femur fractures, with a primary complication being the need for a postoperative blood transfusion. Consequently, current standard practice involves cross-matching two units of red blood cells for each patient preoperatively. This incurs significant costs and is associated with blood product complications for transfused patients who are at low risk. This study aims to identify factors that could increase the risk of requiring a blood transfusion, thereby facilitating the adaptation of preoperative cross-matching practices to reflect individual patient risks rather than using a generalised approach.

METHODS

A retrospective analysis was conducted of 319 patients from a major acute teaching hospital between June 2023 and January 2024, examining risk factors including preoperative haemoglobin levels, age, gender, type and duration of surgery, type of fracture, BMI, use of anticoagulants, and comorbidities (diabetes, hypertension, cancer, chronic obstructive pulmonary disease (COPD)/asthma, heart disease). Binary logistic regression and odds ratios were used to assess their impact on blood loss and transfusion need.

RESULTS

Ninety-nine patients (31%) in our cohort received a blood transfusion. Preoperative haemoglobin (p<0.001) and age (p=0.039) were the only factors found to be significant predictors of the likelihood of needing a blood transfusion. The exponentiation of the B coefficient (Exp(B)) values were 0.920 and 1.040, respectively, indicating a negative correlation for preoperative haemoglobin and a positive correlation for age. Statistical analysis between the group receiving a transfusion versus those who did not showed that patients were significantly older (p<0.001), had lower BMI (p=0.037), and had lower preoperative haemoglobin (p<0.001) in the transfused group. Odds ratios indicated that females (1.34) and patients with hypertension (1.19), cancer (1.09), COPD or asthma (1.06), and heart disease (1.45) were more likely to receive transfusions. Intracapsular fractures (undisplaced 0.12, displaced 0.38) and arthroplasty (0.38) showed lower odds compared to intramedullary (IM) nailing (3.13). The odds ratio changes to less than one for haemoglobin values >110 g/L (<0.7) and increases to values greater than one for age above 80 (>1.27).

CONCLUSION

Increased age and low preoperative haemoglobin significantly raise the risk of hidden blood loss and transfusion need following neck of femur surgery. We suggest further development of a risk prediction model to improve surgical outcomes, reduce healthcare costs, and optimise resource utilisation.