Weve done many columns supporting more restrictive transfusion policies. Our most recent column (see our December 2017 What's New in the Patient Safety World column ) showed that even for cardiac surgery these more restrictive policies should apply. But maybe that does not apply to all cardiac surgery. A new study shows that the transfusion requirement for cardiac revision surgery may be considerably higher than previously reported.
Previous studies had shown transfusion requirements were about 75% higher in cardiac revision surgeries. But a new study shows that, when compared with first-time cardiac surgery, blood product utilization for revision cases was two to four times greater. Analyzing cases between January 2009 and June 2016, researchers at Johns Hopkins (Hensley 2017a, Doyle 2017) found that with CAB (coronary artery bypass) surgeries, the mean transfusion requirements for redo patients were two- to fourfold greater than the non-redo CAB patients. For non-CAB cardiac surgeries the mean transfusion requirements for redo cases were two times greater.
Dr. Hensley noted that microvascular bleeding, when layers of scar tissue from a primary sternotomy are dissected, is common in revision cases but is not easily seen or repaired by surgeons. Revision cases also showed significant increases in bypass or aortic cross-clamping time, which has been linked to increased blood transfusion requirements.
So anesthesiologists must be prepared for the increased transfusion need in revision cases. Blood conservation strategies are important and these patients should also be targeted ahead of surgery, when there is time to increase hemoglobin with erythropoietin or iron supplementation, or by correcting coagulopathies.
Hensley and colleagues had also published some of their findings separately (Hensley 2017b). They note that prior studies comparing these cohorts were performed before patient blood management (PBM) and blood conservation measures were commonplace. Compared to the primary cardiac surgery patients, revision surgery patients required approximately twofold more transfused units intraoperatively and approximately two- to threefold more transfused units for the whole hospital stay. Moreover, intraoperative massive transfusion (>10 RBC units) was substantially more frequent with revision versus primary cardiac surgery (2.6% vs. 0.1% for isolated CAB or valve surgery and 6.1% vs. 1.9% for all other cardiac surgeries). Revision surgery was an independent risk factor for both moderate (6-10 RBC units) and massive intraoperative transfusion.
With all our attention to restrictive transfusion policies, this is an important wake-up call that such restrictive approaches do not apply to revision surgeries (at least cardiac revisions).
Prior columns on potential detrimental effects related to red blood cell transfusions:
Hensley NB, Gupta PB, Yang WW, Frank SM, Brown C. Blood Product Utilization in Revision vs. First-Time Cardiac Surgery: An Update in The Era Of Patient Blood Management. International Anesthesia Research Society 2017 annual meeting (abstract 1879)
As discussed in:
Doyle C. Transfusion Requirements Significantly Increased in Revision Cardiac Surgery
Anesthesiology News 2017; December 15, 2017
Hensley NB, Kostibas MP, Yang WW, et al. Blood utilization in revision versus first-time cardiac surgery: an update in the era of patient blood management. Transfusion 2017; Epub ahead of print 8 October 2017