Safety of ultrarestrictive transfusion protocol as a blood preservation strategy during crisis

ABSTRACT

INTRODUCTION: Blood shortage have emerged as complicating and strategic hurdle during COVID-19 pandemic. We hypothesized that adopting an ultra-restrictive transfusion protocol to preserve blood products use in surgical intensive care units (SICU) is safe and effective compared to current practices. METHODS: Early in the COVID-19 pandemic (on 3/20/2020), our SICU adopted a protocol to change transfusion cutoff to hemoglobin (Hb) of 6 g/dl (or 6.5 g/dl for patients 65 years and older) instead of 7 g/dl. We excluded patients who were COVID+, actively bleeding, or had signs of cardiac ischemia on admission. We compared patients admitted to SICU during 2 months before (PRE) and 2 months after (POST) implementing the protocol who met the transfusion cutoff. Our primary outcome was in-hospital mortality. The Sequential Organ Failure Assessment (SOFA) score on the day of transfusion was calculated. Secondary outcomes were new ischemic changes and total number of packed red blood cells (PRBC) transfused. RESULTS: Our cohort had 261 patients (PRE n=93, POST n=168). Of those, 41 patients had Hb drop below 7 (16 in PRE, 17.2% and 27 in POST, 16.1%). In Post group, 12 patients had Hb drop below 6 and required transfusion (7.1%, p=0.02). There was no difference in gender or age between patients who met transfusion cutoff in either group. There was also no difference in mortality (PRE 5, 31.3% and POST 3, 25%, NS) or ischemic complications (PRE 2, 12.5% and POST 4, 33.3%, NS). Odds ratio of mortality in POST group was 0.62 (95%CI0.08-5.12) adjusted for age, gender, and SOFA score. Mortality rate in POST patients who had Hb>6 g/dl (n=15) was 13.3%. PRBC transfusion per patient was on average 4±3.8 units in PRE group and 2.4±1.5 units in POST group (NS). This represents a potential preservation of 60-100 PRBC units during the 2 months period of implementing the protocol and a potential reduction of 55-73% in blood product utilization. CONCLUSIONS: Ultra-restrictive transfusion protocol appears to be safe and effective in preserving blood products utilization during a shortage crisis. These results are limited by the small sample size and a large multi-center study is warranted. However, these results could present a promising option during a subsequent pandemic crises or other similar disasters.