A novel allocation strategy for blood transfusions: investigating the tradeoff between the age and availability of transfused blood

The supply chain of blood products in the wake of the COVID-19 pandemic: Appointment scheduling and other restrictions

In this work, we formulate the blood products supply chain problem in the wake of disasters such as the COVID-19 (SARS-CoV-2) pandemic using two-stage stochastic programming where uncertainty of both demand and supply is considered. The products considered are red blood cells (RBCs), plasma, and platelets. Age-based demand and blood type substitution are included in our model. A heuristic is developed to solve the instances a commercial optimization software failed to solve in a reasonable amount of time. To obtain managerial insight a sensitivity analysis is conducted. Results of the analysis show that bigger capacities of permanent collection facilities are favored over the mobility of temporary facilities while accounting for blood substitution and age-based demand in the planning phase reduced shortages significantly. Moreover, different objective functions were considered to ensure fairness in distribution of the products among hospitals. The fairer distribution resulted in an increase in the total unmet demand.

Modeling the potential impact on the US blood supply of transfusing critically ill patients with fresher stored red blood cells

Background

Although some studies have suggested that transfusion recipients may have better medical outcomes if transfused with red blood cell units stored for a short time, the overall body of evidence shows mixed results. It is important to understand how using fresher stored red blood cell units for certain patient groups may affect blood availability.

Methods

Based on the Stock-and-Flow simulation model of the US blood supply developed by Simonetti et al. 2014, we evaluated a newly implemented allocation method of preferentially transfusing fresher stored red blood cell units to a subset of high-risk group of critically ill patients and its potential impact on supply.

Results

Simulation results showed that, depending on the scenario, the US blood total supply might be reduced between 2-42%, when compared to the standard of care in transfusion medicine practice. Among our simulated scenarios, we observed that the number of expired red blood cell units modulated the supply levels. The age threshold of the required red blood cell units was inversely correlated with both the supply levels and the number of transfused units that failed to meet that age threshold.

Conclusion

To our knowledge, this study represents the first attempt to develop a comprehensive framework to evaluate the impact of preferentially transfusing fresher stored red blood cells to the higher-risk critically ill patients on supply. Model results show the difficulties to identify an optimal scenario.

Where now for transfusion: the evolution of a paradigm and its logical progression

The development of transfusion over the past century and a half has been described as one of the blessings of modern medicine. But, in some ways, it is emerging as a decidedly mixed blessing, bringing epidemics as well as improved health. Given all the practice has been through, now is the right time to take a critical look at blood transfusion as it is practiced today, and whether it serves the individual patient as effectively as the interests of those who administer it.

Reducing the age of transfused red blood cells in hospitals: ordering and allocation policies

BACKGROUND

Although recent randomized controlled trials have not found increased risk of morbidity/mortality with older red blood cells (RBCs), several large trials will be completed soon providing power to detect smaller risks if indeed they exist. Hence, there may still be a need for inventory management policies that could reduce the age of transfused RBCs without compromising availability or resulting in excessive outdates.

MATERIALS AND METHODS

We developed a computer simulation model based on data from an acute care hospital in Hamilton, Ontario. We evaluated and compared the performance of certain practical ordering and allocation policies in terms of outdate rate, shortage rate and the distribution of the age of issued RBCs.

RESULTS

During the 1-year period for which we analysed the data, 10349 RBC units were transfused with an average issue age of 20·7 days and six units were outdated (outdate rate: 0·06%). Adopting a strict first in, first out (FIFO) allocation policy and an order-up-to ordering policy with target levels set to five times the estimated daily demand for each blood type, reduced the average issue age by 29·4% (to 14·6 days), without an increase in the outdate rate (0·05%) or resulting in any unmet demand. Further reduction of issue age without a significant increase in outdate rate was observed when adopting non-FIFO threshold-based allocation policies and appropriately adjusting the order-up-to levels.

CONCLUSION

A significant reduction of issue age could be possible, without compromising availability or resulting in excessive outdates, by properly adjusting the ordering and allocation policies at the hospital level.

Risk factors for transfusion-associated complications and nonsurvival in dogs receiving packed red blood cell transfusions: 211 cases (2008-2011)

OBJECTIVE

To determine whether the number, volume, or age of transfused packed RBC units; volume of other blood products; or pretransfusion PCV was a risk factor for transfusion-associated complications or nonsurvival in dogs.

DESIGN

Retrospective case series.

ANIMALS

211 client-owned dogs receiving stored packed RBC transfusions.

PROCEDURES

Information collected or calculated from the medical record of each dog included the total number, volume, and dose of packed RBC units; mean age of packed RBC units; number of packed RBC units > 14 days old; age of oldest packed RBC unit; volume and dose of other blood products used; pretransfusion PCV; acute patient physiologic and laboratory evaluation score; transfusion-associated complications; and outcome.

RESULTS

The dose (mL/kg) of other blood products transfused was a risk factor for transfusion-associated complications (OR, 1.03; 95% confidence interval [CI], 1.01 to 1.05). The pretransfusion PCV (OR, 1.13; 95% CI, 1.06 to 1.21) and dose of packed RBCs administered (OR, 1.04; 95% CI, 1.02 to 1.07) were risk factors for nonsurvival. Age of transfused packed RBC units was not identified as a risk factor for transfusion-associated complications or nonsurvival, but the study was statistically underpowered to detect this finding.

CONCLUSIONS AND CLINICAL RELEVANCE

Administration of larger doses of other non-packed RBC blood products was a risk factor for transfusion-associated complications, and a higher pretransfusion PCV and larger dose of packed RBCs administered were risk factors for nonsurvival. Prospective randomized studies are needed to determine whether conservative transfusion strategies will reduce transfusion-associated complications and improve outcome in dogs.

Red blood cell storage: how long is too long?

Red blood cells (RBCs) undergo biochemical and structural changes during storage, commonly referred to as the "storage lesion." Evidence suggests that the longer the RBC product is stored, the less effective is the transfused blood. Many studies linking morbidity to transfusion have not considered duration of RBC storage as a variable that may modulate the effect. In addition, the effects of supply and demand and RBC inventory management strategies have been incompletely investigated. It is possible to envision a blood management system based on modern inventory management strategies that could greatly reduce storage duration.

A stock-and-flow simulation model of the US blood supply

BACKGROUND

Lack of reporting requirements for the amount of blood stored in blood banks and hospitals poses challenges to effectively monitor the US blood supply. Effective strategies to minimize collection and donation disruptions in the supply require an understanding of the daily amount of blood available in the system.

STUDY DESIGN AND METHODS

A stock-and-flow simulation model of the US blood supply was developed to obtain estimates of the daily on-hand availability of blood, with uncertainty and by ABO/Rh type. The model simulated potential impact on supply of using different blood management practices for transfusion: first in-first out (FIFO), using the oldest stored red blood cell units first; non-FIFO likely oldest, preferentially selecting older blood; and non-FIFO likely newest, preferentially selecting younger blood.

RESULTS

Simulation results showed higher estimates of the steady-state of the blood supply level for FIFO (1,630,000 units, 95% prediction interval [PI] 1,610,000-1,650,000) than non-FIFO scenarios (likely oldest, 1,530,000 units, 95% PI 1,500,000-1,550,000; and likely newest, 1,190,000 units, 95% PI 1,160,000-1,220,000), either for overall blood or by blood types.

CONCLUSION

To our knowledge, this model represents a first attempt to evaluate the impact of different blood management practices on daily availability and distribution of blood in the US blood supply. The average storage time before blood is being issued was influenced by blood management practices, for preferences of blood that is younger and also that use specific blood types. The model also suggests which practice could best approximate the current blood management system and may serve as useful tool for blood management.