NoBlood

Jan B. Wade · #1 (**permalink**) 09-25-2005, 09:21 AM

http://www.rednova.com/news/display/...ource=r_health

Preoperative erythropoietin therapy
Canadian Journal of Anesthesia

April 2005

Erythropoietin (EPO) is a hormone that occurs naturally in the body and stimulates bone marrow to make red blood cells. It is produced by the kidneys (ie, 90%) and liver (ie, 10%) in response to anemia or low blood oxygen levels. Erythropoietin is available commercially and can be given as a treatment for a low red blood cell count and as an alternative to blood transfusion.

The efficacy of preoperative EPO therapy for increasing hemoglobin levels and reducing the need for blood transfusions in orthopedic surgery has been demonstrated. Currently, preoperative EPO therapy is not widely used in clinical practice, however, likely because of the impracticality of

* the dosing schedule recommended by efficacy trials that generally require a lead time of four weeks and

* the high cost of the recommended dose of four 40,000- international unit injections.

Beginning in July 1999, the preoperative EPO therapy dosing schedule was adjusted for eligible patients who were anemic and scheduled to undergo total joint arthroplasty (TJA) at a university hospital in Canada. Instead of the recommended four injections of EPO, a maximum of three were administered, and instead of using a dose of 600 international units kg^sup -1^, a total of 20,000 international units were administered to patients who weighed less than 70 kg, and 40,000 international units were administered to those who weighed more than 70 kg. The objective of this observational study was to assess the efficacy of this more practical dosing schedule for preoperative EPO therapy in reducing allogeneic red blood cells transfusion in patients undergoing TJA.4

Patients who underwent TJA from January 1999 through June 2003 were assessed by the Perioperative Blood Conservation Program and, depending on their baseline hemoglobin levels, were offered one of two blood conservation methods-either preoperative autologous donation or preoperative EPO therapy-as part of their routine care. Patients who met the hemoglobin level cutoff point, had sufficient time before surgery for preoperative EPO therapy, and opted for this treatment were designated as the treatment group. Patients in the treatment group who weighed less than 70 kg received 20,000 international units EPO, and those who were heavier than 70 kg received 40,000 international units EPO three days before surgery and seven days before surgery if that amount of time was available. In addition, they received dietary iron supplementation.

Patients who met the hemoglobin cutoff but did not have sufficient time for preoperative EPO therapy or who opted against this therapy were considered to be the control group. These patients also were advised to take dietary iron supplementation. Data collected on all patients included biographical data, American Society of Anesthesiologists (ASA) classification, baseline and postoperative hemoglobin and creatinine concentrations, duration of surgery, exposure to blood products, and postoperative length of hospital stay. Common statistical techniques, including frequencies and percentages, t tests, and analysis of variance were used to analyze the data.

Findings. Of the 1,782 patients who underwent TJA, 171 (10%) had preoperative autologous donation and were excluded from the analysis. The analysis was completed on 1,611 patients of whom 770 (48%) were anemic (ie, hemoglobin less than 130 gL ^sup -1^) and 503 (31%) received transfusion. Two hundred fourteen patients received preoperative EPO therapy, and their transfusion rate was 16% compared to a transfusion rate of 56% in those who did not receive preoperative EPO therapy (P < .0001). The adjusted odds ratio for transfusion with preoperative EPO therapy was 0.33, 95% CI 0.21- 0.49.

Clinical implications. The results of this observational study suggest that preoperative EPO therapy employing a more flexible dosing schedule is highly effective in reducing perioperative blood transfusions when used in anemic : patients undergoing elective TJA. Although this dosing schedule would appear to have a positive affect on cost, perioperative managers should consider gathering more cost- specific data.

This information is intended for general use only. The clinical implications are specific to the abstracted article only. Individuals intending to put these findings into practice are strongly encouraged to review the original article to determine its applicability to their setting.

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K Karkouti et al, "Erythropoietin is an effective clinical modality for reducing RBC transfusion in joint surgery," Canadian Journal of Anaesthesia 52 (April 2005) 362-368.