Comparison of hypotensive epidural anaesthesia and spinal anaesthesia on blood loss and coagulation during and after total hip arthroplasty

BACKGROUND: Hypotensive epidural anaesthesia (HEA) is a technique for reducing peroperative blood loss by significantly lowering mean arterial pressure (MAP). METHODS: Thirty patients scheduled for primary total hip arthroplasty were given HEA (n=15) or spinal anaesthesia (SPA) (n= 15) with bupivacaine in random order. The dose of bupivacaine was titrated to provide epidural blockade up to T1-T4 and spinal blockade at least to T10. Intravenous adrenaline infusion was adjusted to achieve a MAP of about 50-60 mmHg in the HEA group. During SPA MAP was maintained above 70 mmHg with ephedrine, as needed. RESULTS: Intraoperative blood loss (median and 25th and 75th percentiles) was 400 ml (163-575) in the HEA group and 900 ml (663-1,100) in the SPA group (P<0.05). At 3 h postoperatively cumulative blood loss was still smaller in the HEA group (600 ml versus 1,100 ml, P<0.05). The cumulative number of transfused packed red cell concentrate (PRC) units was smaller in the HEA group than in the SPA group during surgery and postoperatively. Prothrombin time value was smaller in the SPA than in the HEA group (69% versus 79%, P<0.05) at 3 h postoperatively. D-dimer concentrations increased more in the SPA group at the end of the surgery and 3 h postoperatively (P<0.05). CONCLUSIONS: HEA resulted in reduced blood loss due to hypotension and reduced number of transfused PRC units during total hip arthroplasty. Based on lower prothrombin time value and higher D-dimer concentrations in the SPA group, the coagulation system might be better preserved during HEA than SPA.