Comparative changes of pre-operative autologous transfusions and peri-operative cell salvage in the United States.

BACKGROUND: With improved safety of allogeneic blood supply, the use of preoperative autologous donations (PADs) and perioperative autologous cell salvage (PACS) has evolved. This study evaluated temporal trends in PAD and PACS use in the United States. METHODS: The National Inpatient Sample database, a stratified probability sample of 20% of hospitalizations in the United States, was used to compare temporal trends in hospitalizations reporting use of PADs and PACS from 1995 to 2015. Factors associated with their use were examined between 2012 and 2015 with use of multivariable Poisson regression. Sampling weights were applied to generate nationally representative estimates. RESULTS: There was a steady decrease in hospitalizations reporting PAD transfusions from 27.90 per 100 000 in 1995 to 1.48 per 100 000 hospitalizations in 2015 (P-trend <.001). In contrast, PACS increased from a rate of 1.16 per 100 000 in 1995 to peak of 20.51 per 100 000 hospitalizations in 2008 and then steadily declined (P-trend<.001). Higher odds of PACS and PADs were observed in older patients, elective procedures (vs urgent), and urban teaching/nonteaching hospitals (vs rural hospitals) (P < .001). PACS was more common in hospitalizations in patients with higher levels of severity of illness as compared to those with minor severity (adjusted prevalence ratio [adjPR], 2.39; 95% confidence interval [CI], 2.08-2.73; P<.001), while PADs were performed less often in patients with higher underlying severity of illness (All Patient Refined Diagnosis Related Groups, 4 vs 1, adjPR, 0.61; 95% CI, [0.39-0.95]; P = .028). CONCLUSIONS: There was a significant decrease in PAD red blood cell transfusions, while PACS has increased and subsequently decreased; PACS plays an important role in surgical blood conservation. The subsequent decline in PACS likely reflects further optimization of transfusion practice through patient blood management programs and improvement of surgical interventions.

Clinical Practice Guidelines From the AABB: Red Blood Cell Transfusion Thresholds and Storage.

Importance: More than 100 million units of blood are collected worldwide each year, yet the indication for red blood cell (RBC) transfusion and the optimal length of RBC storage prior to transfusion are uncertain. Objective: To provide recommendations for the target hemoglobin level for RBC transfusion among hospitalized adult patients who are hemodynamically stable and the length of time RBCs should be stored prior to transfusion. Evidence Review: Reference librarians conducted a literature search for randomized clinical trials (RCTs) evaluating hemoglobin thresholds for RBC transfusion (1950-May 2016) and RBC storage duration (1948-May 2016) without language restrictions. The results were summarized using the Grading of Recommendations Assessment, Development and Evaluation method. For RBC transfusion thresholds, 31 RCTs included 12 587 participants and compared restrictive thresholds (transfusion not indicated until the hemoglobin level is 7-8 g/dL) with liberal thresholds (transfusion not indicated until the hemoglobin level is 9-10 g/dL). The summary estimates across trials demonstrated that restrictive RBC transfusion thresholds were not associated with higher rates of adverse clinical outcomes, including 30-day mortality, myocardial infarction, cerebrovascular accident, rebleeding, pneumonia, or thromboembolism. For RBC storage duration, 13 RCTs included 5515 participants randomly allocated to receive fresher blood or standard-issue blood. These RCTs demonstrated that fresher blood did not improve clinical outcomes. Findings: It is good practice to consider the hemoglobin level, the overall clinical context, patient preferences, and alternative therapies when making transfusion decisions regarding an individual patient. Recommendation 1: a restrictive RBC transfusion threshold in which the transfusion is not indicated until the hemoglobin level is 7 g/dL is recommended for hospitalized adult patients who are hemodynamically stable, including critically ill patients, rather than when the hemoglobin level is 10 g/dL (strong recommendation, moderate quality evidence). A restrictive RBC transfusion threshold of 8 g/dL is recommended for patients undergoing orthopedic surgery, cardiac surgery, and those with preexisting cardiovascular disease (strong recommendation, moderate quality evidence). The restrictive transfusion threshold of 7 g/dL is likely comparable with 8 g/dL, but RCT evidence is not available for all patient categories. These recommendations do not apply to patients with acute coronary syndrome, severe thrombocytopenia (patients treated for hematological or oncological reasons who are at risk of bleeding), and chronic transfusion-dependent anemia (not recommended due to insufficient evidence). Recommendation 2: patients, including neonates, should receive RBC units selected at any point within their licensed dating period (standard issue) rather than limiting patients to transfusion of only fresh (storage length: <10 days) RBC units (strong recommendation, moderate quality evidence). Conclusions and Relevance: Research in RBC transfusion medicine has significantly advanced the science in recent years and provides high-quality evidence to inform guidelines. A restrictive transfusion threshold is safe in most clinical settings and the current blood banking practices of using standard-issue blood should be continued.