Plasma transfusion practices: A multicentre electronic audit

The historical origins of modern international normalized ratio targets

Prothrombin time (PT) and its derivative international normalized ratio (INR) are frequently ordered to assess the coagulation system. Plasma transfusion to treat incidentally abnormal PT/INR is a common practice with low biological plausibility and without credible evidence, yet INR targets appear in major clinical guidelines and account for the majority of plasma use at many institutions. In this article, we review the historical origins of INR targets. We recount historical milestones in the development of the PT, discovery of vitamin K antagonists (VKAs), motivation for INR standardization, and justification for INR targets in patients receiving VKA therapy. Next, we summarize evidence for INR testing to assess bleeding risk in patients not on VKA therapy and plasma transfusion for treating mildly abnormal INR to prevent bleeding in these patients. We conclude with a discussion of the parallels in misunderstanding of historic PT and present-day INR testing with lessons from the past that might help rationalize plasma transfusion in the future.

Reducing blood product wastage through the inter-hospital redistribution of near-outdate inventory

BACKGROUND

Hospital transfusion services order blood products to satisfy orders and maintain inventory levels during unexpected periods of increased blood demand. Surplus inventory may outdate before being allocated to a recipient. Blood product outdating is the largest contributor to blood wastage.

STUDY DESIGN

A province-wide redistribution program was designed and implemented to redistribute near-outdate plasma protein and related blood products from low-usage to high-usage hospitals. Program operations and details are described in this paper. Two transport container configurations were designed and validated for transport of all blood products. A cost-analysis was performed to determine the effectiveness of this redistribution program.

RESULTS

A total of 130 hospital transfusion services contributed at least one near-outdate blood product for redistribution between January 2012 and March 2020. These services redistributed 15,499 products through 3412 shipments, preventing the outdating of $17,570,700 CAD worth of product. Program costs were $14,900 for shipping and $30,000 for staffing. Failed time limits or non-compliance with packing configurations resulted in $388,200 worth of blood products (97 shipments containing 816 products) being discarded. Courier transport delays was the most common reason (42/97; 43%) for transport failure.

CONCLUSION

Redistributing near-outdate blood products between hospitals is a feasible solution to minimize outdating. Despite heterogeneity of Canadian blood product inventory, all products (each with unique storage and transport requirements) were successfully redistributed in one of two validated and simple containers. Total operation costs of this program were small in comparison to the $17.6 million in savings associated with preventing the discard of outdated products.

A review and analysis of outcomes in randomized clinical trials of plasma transfusion in patients with bleeding or for the prevention of bleeding: The BEST collaborative study

BACKGROUND

Previous systematic reviews have revealed an inconsistency of outcome definitions as a major barrier in providing evidence-based guidance for the use of plasma transfusion to prevent or treat bleeding. We reviewed and analyzed outcomes in randomized controlled trials (RCTs) to provide a methodology for describing and classifying outcomes.

STUDY DESIGN AND METHODS

RCTs involving transfusion of plasma published after 2000 were identified from a prior review (Yang 2012) and combined with an updated systematic literature search of multiple databases (July 1, 2011 to January 17, 2023). Inclusion of publications, data extraction, and risk of bias assessments were performed in duplicate. (PROSPERO registration number is: CRD42020158581).

RESULTS

In total, 5579 citations were identified in the new systematic search and 22 were included. Six additional trials were identified from the previous review, resulting in a total of 28 trials: 23 therapeutic and five prophylactic studies. An increasing number of studies in the setting of major bleeding such as in cardiovascular surgery and trauma were identified. Eighty-seven outcomes were reported with a mean of 11 (min-max. 4-32) per study. There was substantial variation in outcomes used with a preponderance of surrogate measures for clinical effect such as laboratory parameters and blood usage.

CONCLUSION

There is an expanding literature on plasma transfusion to inform guidelines. However, considerable heterogeneity of reported outcomes constrains comparisons. A core outcome set should be developed for plasma transfusion studies. Standardization of outcomes will motivate better study design, facilitate comparison, and improve clinical relevance for future trials of plasma transfusion.

Plasma: indications, controversies, and opportunities

Plasma is overused as a blood product worldwide; however, data supporting appropriate use of plasma is scant. Its most common utilization is for treatment of coagulopathy in actively bleeding patients; it is also used for coagulation optimization prior to procedures with specific coagulation profile targets. A baseline literature review in PUBMED and Google Scholar was done (1 January 2000 to 1 June 2023), utilizing the following search terms: plasma, fresh frozen plasma, lyophilized plasma, indications, massive transfusion protocol, liver disease, warfarin reversal, cardiothoracic surgery, INR < 2. An initial review of the titles and abstracts excluded all articles that were not focused on transfusional medicine. Additional references were obtained from citations within the retrieved articles. This narrative review discusses the main indications for appropriate plasma use, mainly coagulation factor replacement, major hemorrhage protocol, coagulopathy in liver disease, bleeding in the setting of vitamin K antagonists, among others. The correlation between concentration of coagulation factors and INR, as well as the proper plasma dosing with its volume being weight-based, is also discussed. A high value approach to plasma utilization is supported with a review of the clinical situations where plasma is overutilized or unnecessary. Finally, a discussion of novel plasma products is presented for enhanced awareness.