Timing of Low Molecular Weight Heparin Administration in Breast Surgery and Post-Operative Haematoma Formation.

Aims The aims of this study were to: identify current practice regarding low molecular weight heparin (LMWH) prophylaxis in elective breast surgery, to determine if timing of administration of LMWH prophylaxis or specific patient demographic factors impacts the rate of post-operative haematoma formation. Methods Retrospective cohort study involving 100 patients who underwent elective breast surgery in a tertiary centre in Ireland in 2017. Medical charts were reviewed to collect data on; timing of LMWH administration, incidence of post-operative haematoma and patient's age, BMI, smoking status and anti-coagulant use. Statistical analysis was then performed. Results Forty-two patients (42%) received enoxaparin pre-operatively and thirty-one patients (31%) post-operatively. Incidence of post-operative haematoma was 4% (n=4). Of the haematoma group, three patients (75%) received post-operative enoxaparin (p=0.166). Independent patient factors did not significantly impact rate of haematoma formation. Conclusions Post-operative haematoma rate is 4%. Timing of LMWH prophylaxis administration did not significantly affect this rate.