Reassessing the Need for Preoperative Transfusions in Sickle Cell Disease Patients With an Elevated Baseline Hemoglobin-A Retrospective Study

Background: Current guidelines recommend a preoperative hemoglobin of 10.0 g/dL in patients with sickle cell disease [SCD], however, this threshold continues to be an area of controversy. Previous studies demonstrating the benefits of preoperative transfusions have largely not captured patients with elevated baseline hemoglobin, in part due to low hydroxyurea uptake and exclusion of nonhemoglobin SS SCD.

Materials and methods: We conducted a retrospective chart review of patients with SCD <18 years of age undergoing low and medium-risk procedures at 2 academic medical centers in Canada between 2007 and 2017. The primary objective was to study the association of preoperative transfusion on postoperative complications in patients with SCD with baseline hemoglobin between 9.0 and 10.0 g/dL. Multivariable logistic regression was used to estimate the adjusted effect of preoperative transfusion on the risk of developing postoperative complications.

Results: In all, 159 procedures in patients with hemoglobin <9.0 g/dL [Hb <9.0 ] and 173 procedures in patients with hemoglobin between 9.0 and 10.0 g/dL [Hb 9.0-10.0 ] were analyzed. In the absence of preoperative transfusion, Hb 9.0-10.0 patients had lower overall complications [23% vs. 34%] compared with Hb <9.0 patients [OR 0.29, 95% CI 0.12-0.72, P =0.008]. In total, 75% of Hb <9.0 and 21% of Hb 9.0-10.0 patients received a preoperative simple transfusion. Transfusion was associated with increased risk of postoperative complications in Hb 9.0-10.0 [OR 3.02, 95% CI 1.26-7.23, P =0.013], but not Hb <9.0 patients [OR 0.64, 95% CI 0.28-1.45, P =0.30].

Conclusions: Simple transfusion may not be warranted in Hb 9.0-10.0 patients undergoing low-risk procedures. Prospective studies validating these findings are needed.