Investigation of perioperative hidden blood loss of unstable intertrochanteric fracture in the elderly treated with different intramedullary fixations.

OBJECTIVE: Our aim was to investigate perioperative hidden blood loss (PHBL) of unstable intertrochanteric fracture (UIF) in the elderly treated with different intramedullary fixations.

PATIENTS AND METHODS: 120 consecutive elderly patients with UIF treated by intramedullary nails between January 2013 and September 2016 were enrolled in the retrospective study, including 52 patients (mean age 79.6±6.3) for the Third generation Gamma Nail (TGN), 51 patients (mean age 79.3±7.4) for the Proximal Femoral Nail Anti-rotation (PFNA), 17 patients (mean age 76.2±5.8) for the Intertrochanteric Antegrade Nail (InterTan). The PHBL and total blood loss (TBL) were calculated based on the haematocrit change from admission to 72h after the operation. The differences of perioperative visible blood loss (PVBL), PHBL, and TBL among TGN, PFNA, and InterTan were compared. The statistical analysis was made using One-way ANOVA for comparison among groups, and Mann-Whitney U test was conducted to a direct comparison between two procedures.

RESULTS: The mean TBL of all patients was 911.3mL (range, 446.8-1697.3mL), whereas the mean PHBL was 771.8mL (range, 331.5-1756.5mL), being about 84.5% of TBL. The PVBL in the TGN group was 201.4±101mL, the TBL was 871.3±196.1mL, the PHBL was 709.4±181mL. In the PFNA group, the PVBL was 147.3±81.6mL, the TBL was 892.6±234.8mL, and the PHBL was 787.7±250.9mL. The InterTan group had a PVBL of 246.5±89.7mL, the TBL was 1086.1±198.1mL where the PHBL was 910±167.9mL. The patients in the InterTan group had the largest amount of PHBL and TBL among three groups (P<0.01), there was no difference between TGN and PFNA group (P=0.2141).

CONCLUSIONS: Elderly patients with UIF treated by intramedullary fixations always have a significant amount of PHBL, which is much greater than that observed intra-operatively. Regular perioperative measurements of full blood count are necessary to avoid anaemia. InterTan nail is associated with a significantly higher PHBL than that of TGN and PFNA, which needs to be monitored carefully in usual clinical practice.