Hypotensive epidural anesthesia in total knee replacement without tourniquet: reduced blood loss and transfusion

[corrected] For decades, hypotensive anesthesia has been used in an attempt to reduce intraoperative blood loss. Hypotensive epidural anesthesia (HEA) is a relatively new technique in hypotensive anesthesia. Use of a tourniquet has been shown to be associated with a higher risk of cardiovascular and thromboembolic complications. The effect of HEA on blood loss and need for transfusion in total knee replacement (TKR) is not known.

Thirty consecutive patients scheduled for TKR were randomized to HEA without tourniquet or spinal anesthesia with the use of a tourniquet (SPI). HEA was performed as an epidurally induced sympathetic block and there was an infusion of low-dose epinephrine to stabilize the circulation.

Intraoperative mean arterial blood pressure was 48 mm Hg (HEA) versus 83 mm Hg (SPI) (P <.001). Intraoperative blood loss was 146 mL (HEA) versus 13 mL (SPI) (P <.001). Postoperative blood loss at any time was significantly reduced in the HEA group, and total loss of blood was 1,056 mL (HEA) versus 1,826 mL (SPI) (P <.001). Half of the bleeding took place during the first 3 postoperative hours and 80% during the first 24 hours. In the HEA group, 57% of the patients went through surgery and the hospital stay without receiving blood transfusion versus 19% in the SPI group (P <.05). There was a significantly reduced amount of blood transfusion in the HEA group (193 mL) versus 775 mL in the SPI group (P <.005). No cardiopulmonary, cerebral, or renal complications were registered.

We conclude that HEA is a safe technique that allows TKR without a tourniquet. Compared with spinal anesthesia, the use of HEA for TKR significantly reduces blood loss and the need for blood transfusion.