Ranking the effectiveness of autologous blood conservation measures through validated modeling of independent clinical data

Supportive Care of Hematopoietic Stem Cell Donors

Supportive care needs for hematopoietic stem cell recipients have been studied. Less is known about the care needs of stem cell donors. Care challenges arise at donor selection, preparation for the donation, the donation procedure and the immediate and long-term after-care. Care needs were analyzed for 1,831 consecutive bone marrow and peripheral stem cell donors at MedStar Georgetown University Hospital between January 2018 and August 2023 in support of a review of the current literature. During the selection, related donors may experience psychological pressures affecting their motivation, while donation centers may be willing to accept co-morbidities in these donors which might preclude donation in unrelated peers. For bone marrow donations, it is important to select donors not only according to optimal genetic matching criteria but also according to suitable donor/recipient weight ratios, to facilitate sufficient stem cell yields. During the donation preparation phase, side effects and complications related to stem cell stimulation must be anticipated and managed for peripheral cell donors, while the pros and cons of autologous blood donation should be evaluated carefully for bone marrow donors. The stem cell donation procedure itself carries potential side effects and complications as well. Peripheral cell donors may require a central line and may encounter hypocalcemia, thrombocytopenia, and anemia. Bone marrow donors face risks associated with anesthesia, blood loss and pain. Post-procedure care focusses on pain management, blood cell recovery and the psychological support necessary to regain a high quality-of-life existence. Hematopoietic stem donors are giving part of themselves to save another's life. They deserve comprehensive supportive care to accompany them throughout the donation process.

Developing a predictive risk score for perioperative blood transfusion: a retrospective study in patients with oral and oropharyngeal squamous cell carcinoma undergoing free flap reconstruction surgery

Background

A simple and accurate scoring system to predict risk of blood transfusion in patients having surgical tumor resection with immediate free flap reconstruction primary surgery for oral and oropharyngeal squamous cell carcinoma (OOSCC) is lacking. Anticipating the blood transfusion requirements in patients with oral cancer is of great clinical importance. This research aimed to propose a valid model to predict transfusion requirements in patients undergoing surgery with free flap reconstruction for an OOSCC.

Methods

This retrospective study consisted of 385 patients who underwent oncologic surgery with immediate free flap reconstruction for locally advanced OOSCC from 2012 to 2019. The primary outcome measured was the exposure of patients to perioperative allogeneic blood transfusion. Based on a multivariate model of independent risk variables and their odds ratio, a blood transfusion risk score (TRS) was developed to predict the likelihood of the perioperative blood transfusion. The discriminatory accuracy of the model was evaluated using the area under the receiver operating characteristic (ROC) curve, and Youden index was used to identify the optimal cut-point.

Results

Logistic regression analyses identified lymph node status, preoperative hemoglobin (Hb) levels, bone resection, osseous free tissue transfer, and operative duration were identified as independent predictors of blood transfusion. A TRS integrating these variables was separated into three categories. The TRS assessed the transfusion risk with good predictive ability, with an overall area under the ROC curve (AUC) was 0.826. At the optimal cut-point of 5.5, the TRS had a sensitivity of 72.3% and a specificity of 78.2%. The ROC analysis showed that patients with a TRS of 5.5 or more had a greater requirement for perioperative transfusion.

Conclusions

The use of the integer-based TRS allowed the identification of high-risk patients who may require perioperative transfusion undergoing tumor resection surgery for the treatment of OOSCC.

Predictive factors for the development of anemia after hematopoietic stem cell donation

BACKGROUND

Although Hematopoietic Stem Cells (HSC) donation through bone marrow (BM) and peripheral blood (PB) are usually safe procedures, adverse events are expected. One of the most common events especially among BM donors (BMD) is the development of anemia. To protect the BMD and preserve the hemoglobin levels, many centers collect autologous pre-procedure blood, but the actual benefits of this procedure is controversial.

METHODS AND MATERIALS

This study analyzed retrospectively data to observe what factors may influence the occurrence of post-donation anemia and also evaluate the relevance of autologous red blood cell pre procedure donation (PAD).

RESULTS

The development of immediately post donation anemia (IP) was higher in BMD than in PB donors (64.2% BMD and 10.7% PBD, P < .001) and also in late post donation (LP) (28.4% BMD and 3.6% PBD, P = .007). The study demonstrated an association between PAD and anemia in IP (72.7% with anemia and 27.3% without anemia, P = .006) and an association between the volume of red blood cells in the donated hematopoietic product and the development of anemia in LP (356.3 mL and 297.8 mL, P = .037).

CONCLUSION

In conclusion, collection of HSC through BM is a risk factor for anemia and PAD is a risk factor for IP anemia.

The Effect of Antifibrinolytic Use on Intraoperative Cell Salvage: Results from a National Registry of Surgical Procedures

Intraoperative cell salvage (ICS) is a critical component of any blood management program involving surgery with a high potential for blood loss. The introduction of antifibrinolytics (AF) may reduce blood loss. The purpose of this study was to evaluate the use of AF on ICS in non-cardiac surgical procedures. Following institutional review board approval, 69,935 consecutive case records between January 2016 and September 2019 from a national registry of adult surgical patients were reviewed. Procedure types were stratified into one of nine surgical categories: general (GN, n = 1,525), neurosurgical (NS, n = 479), obstetric (OB, n = 1,563), cervical spine (CS, n = 2,701), lumbar spine (LS, n = 38,383), hip arthroplasty (HA, n = 13,327), knee arthroplasty (KA, n = 596), vascular (VA, n = 9,845), or orthopedic other (OO, n = 1,516). The primary endpoint was the use of AF with the secondary endpoints ICS shed blood volume and volume available for return. The overall use of AF across all surgical procedures increased from 21.4% in 2016 to 25.4% in 2019. The greatest increases were seen in NS (4.4% to 16.2%), LS (13.7% to 23.1%), and HA (55.8% to 61.9%). For several procedure types, there was an initial increase then either a leveling off or a decline in AF use: OB initially increased from 6.2% to 10.8% in 2018, whereas GN (9.4% to 7.2%) and VA surgery declined slightly (9.9% to 5.7%). When comparing patients who did not receive AF with those who did, there were similar volumes of ICS available for return in all groups, except for LS, GN, and VA, where lower volumes were seen in the No-AF groups. The use of AF has increased each year over the 4-year period in most of the surgical categories, but several have declined. There may be a beneficial effect of AF with lower ICS volumes available for return in a few groups.

Preoperative autologous blood donation in adult bone marrow donors: reappraisal of a single-centre experience

To avoid risk for allogeneic transfusions in healthy bone marrow (BM) donors, 1-2 preoperative autologous blood donations (PAD) are usually collected before the BM harvest. We analysed the haematological parameters in BM donors before and after the harvest, to assess the efficacy of this practice in limiting the postharvest anaemia. Overall, 102 consecutive donors underwent BM harvest preceded by one (26 cases) or two PAD (76 cases), which were infused during BM collection. We analysed the parameters related to donors, PAD timing and BM graft characteristics. PAD induced a significant decrease in Hb (from 14·6 g/dl, IQ range 13·3-15·5 to12·9 g/dl, IQ range 11·8-13·9; P < 0·0001) in all donors, with a median Hb loss at day -1 of 10·9% (IQ range 6·8-14·2). The PAD-related Hb decrease was independent of sex or number of PAD, and was inversely related to the time elapsed from first or last PAD. In comparison with values recorded at day-1, BM harvest produced an additional Hb decrease, accounting for a median Hb loss of 18·9% (IQ range 14·9-24·4). Overall, in comparison with pre-PAD values, Hb levels at day +1 were reduced of 28·9% (IQ range 23·6-32·2), independently if donors had 1 or 2 PAD reinfused. In conclusion, these data show that two PAD do not carry any advantage over one PAD. An eventual benefit of PAD can be achieved only if an adequate interval between PAD and BM harvest elapses. Prospective randomized studies could be worth to establish if any role for PAD does exist in BM donors.

The effectiveness of acute normolvolemic hemodilution and autologous prime on intraoperative blood management during cardiac surgery

Objective:

Intraoperative blood management during cardiac surgery is a multifaceted process incorporating various interventions directed at optimizing oxygen delivery and enhancing hemostasis. The purpose of this study was to evaluate the effects of acute normovolemic hemodilution (ANH) and autologous priming (AP) on preserving the hematocrit during cardiopulmonary bypass (CPB).

Method:

Case records from a national registry of adult patients who underwent cardiac surgery between January and October 2016 were reviewed. Groups were determined as follows: ANH, AP, ANH+AP or Neither. Primary endpoint was first the hematocrit on CPB with secondary endpoints of hematocrit drift and red blood cell (RBC) transfusion rate.

Results:

Eighteen thousand and twenty-four (18,024) consecutive patients were reviewed. The first CPB hematocrit was lowest in the ANH group (26.5%±4.4%) and highest in ANH+AP patients (27.5%±4.8%) (p<0.001). The change in hematocrit was greatest in the ANH group (8.3%±3.9%) compared to both the AP (6.4%±3.8%) and ANH+AP (6.9%±4.1%) groups (p<0.001). Intraoperative RBC transfusions were as follows: ANH 26 (7.8%), AP 2,531 (20.0%), ANH+AP 287 (10.3%) and Neither 592 (26.7%) (p<0.001).

Conclusions:

Regression results show that the use of ANH will result in the greatest decline in hematocrit values. When combined with AP, higher hematocrits and lower transfusions were seen.

Indications and organisational methods for autologous blood transfusion procedures in Italy: results of a national survey

INTRODUCTION

Pre-operative donation of autologous blood is a practice that is now being abandoned. Alternative methods of transfusing autologous blood, other than predeposited blood, do however play a role in limiting the need for transfusion of allogeneic blood. This survey of autologous blood transfusion practices, promoted by the Italian Society of Transfusion Medicine and Immunohaematology more than 2 years after the publication of national recommendations on the subject, was intended to acquire information on the indications for predeposit in Italy and on some organisational aspects of the alternative techniques of autotransfusion.

MATERIALS AND METHODS

A structured questionnaire consisting of 22 questions on the indications and organisational methods of autologous blood transfusion was made available on a web platform from 15 January to 15 March, 2013. The 232 Transfusion Services in Italy were invited by e-mail to complete the online survey.

RESULTS

Of the 232 transfusion structures contacted, 160 (69%) responded to the survey, with the response rate decreasing from the North towards the South and the Islands. The use of predeposit has decreased considerably in Italy and about 50% of the units collected are discarded because of lack of use. Alternative techniques (acute isovolaemic haemodilution and peri-operative blood salvage) are used at different frequencies across the country.

DISCUSSION

The data collected in this survey can be considered representative of national practice; they show that the already very limited indications for predeposit autologous blood transfusion must be adhered to even more scrupulously, also to avoid the notable waste of resources due to unused units.Users of alternative autotransfusion techniques must be involved in order to gain a full picture of the degree of use of such techniques; multidisciplinary agreement on the indications for their use is essential in order for these indications to have an effective role in "patient blood management" programmes.

[Impact of acute normovolemic hemodilution on primary hemostasis]

BACKGROUND

Acute normovolemic hemodilution (ANH) is performed with the intention to reduce the requirement for allogeneic blood transfusions. After preoperative withdrawal of whole blood, corresponding amounts of crystalloids and/or colloids are infused to maintain normovolemia. The main benefit of ANH is the availability of whole blood containing red blood cells, clotting factors and platelets for reinfusion after removal during the dilution process. Until retransfusion whole blood components are stored at the patient's bedside in the operating theatre.

AIM

It was the aim of the present investigation to analyze potential changes in ex vivo induced platelet aggregation in stored blood components.

MATERIAL AND METHODS

After obtaining approval 15 patients undergoing complex cardiac surgery were enrolled into this prospective observational study. Acute normovolemic hemodilution (ANH) was routinely performed in this collective based on institutional standards. Besides analyses of pH and plasma concentrations of ionized calcium and hemoglobin, hematological analyses included aggregometric measurements using multiple electrode aggregometry (MEA, Multiplate®, Roche, Grenzach, Germany). Ex vivo platelet aggregation was induced using arachidonic acid (ASPI test), as well as thrombin receptor activating peptide (TRAP test) and adenosine diphosphate (ADP test). Laboratory analyses were performed before beginning ANH (baseline), as well as immediately (T1), 30 min (T2), 60 min (T3), 90 min (T4), 120 min (T5), 150 min (T6) and 180 min (T7) after beginning of storage. The areas under the aggregation curves (AUC) in the MEA were defined as primary (ASPI test) and secondary endpoints (ADP test, TRAP test).

RESULTS

As compared to baseline, arachidonic acid induced platelet aggregation was significantly reduced at T1 [77 U (68/94 U) vs. 53 U (25/86 U), p = 0.003] and each consecutive measuring point. As compared to T1 (begin of storage), arachidonic acid induced platelet aggregation was significantly reduced at T4 [26 U (14/54 U); p = 0.002], T5 [30 U (21/36 U); p = 0.007], T6 [25 U (17/40 U); p = 0.004] and T7 [28 U (17/39 U); p < 0.001]. The extent of ex vivo induced platelet aggregation in the TRAP test and ADP test remained unchanged during the study period. The pH as well as the concentrations of ionized calcium and hemoglobin remained unchanged in the blood component during storage.

CONCLUSION

The results of the present study indicate that disturbances of platelet aggregation may occur during storage of whole blood components prepared for the purpose of ANH. Further investigations are needed to analyze whether the observed phenomena are of hemostatic relevance.