Development and validation of a scoring system to predict vasovagal reaction upon whole-blood donation.

BACKGROUND AND OBJECTIVES: Risk factors for vasovagal reaction (VVR) have been extensively studied. With knowledge of the relative importance of these risk factors for VVR, collection staff could take care of blood donors from the same standpoint, leading to improved donor safety. We therefore developed a scoring system to predict VVR, which incorporates registration information. MATERIALS AND METHODS: Pre-syncopal and syncopal symptoms, as well as on- and off-site reactions, are included in this analysis as VVR. We defined the donor status as follows: first-time donors, repeat donors with no history of reaction and repeat donors with a history of reaction. We prepared two datasets: whole-blood donations at a blood donation site in Tokyo between January 2019 and December 2019 were included in training data (n = 361,114), and whole-blood donations between January 2020 and August 2020 were included in testing data (n = 216,211). RESULTS: The most important variable was the donor status, followed by age, estimated blood volume and height. We integrated them into a scoring system. Training and testing datasets were combined (n = 577,325), and VVR rates in groups with scores of 0, 1, 2, 3, 4 and 5 or more were 0.09% (95% CI: 0.081%-0.10%), 0.33% (95% CI: 0.31%-0.36%), 0.87% (95% CI: 0.78%-0.96%), 1.17% (95% CI: 1.05%-1.30%), 2.15% (95% CI: 1.98%-2.32%) and 3.11% (95% CI: 2.90%-3.34%), respectively. CONCLUSION: The scoring system enables staff to significantly predict VVR and may help them to identify donors at increased risk of experiencing syncope, thereby mitigating the negative impact of VVR on donor safety and return by paying close attention to high-risk donors.

Syncopal-type reactions tend to be delayed and result in falls among elderly blood donors.

BACKGROUND: Delayed syncopal-type complications are infrequent among blood donors, but sometimes have critical consequences, such as severe injury. We retrospectively investigated the characteristics of donors with delayed syncopal-type complications or falls. STUDY DESIGN AND METHODS: We defined a delayed reaction (DR) as syncopal-type complications occurring >20 min after needle removal. Subjects were stratified by sex, age, estimated blood volume (EBV), body mass index (BMI) and frequency of donation. Multiple logistic regression analysis and propensity score weighted M estimation were performed to evaluate the covariate-adjusted risk of syncopal DRs among donors giving 400 ml of whole blood (WB). The DR rate was calculated as the number of DRs divided by the number of all syncopal-type reactions after needle removal. The risk of falls was assessed similarly. Donors who discontinued before completing phlebotomy (donation of 400 ml) were excluded. RESULTS: Among 3818 syncopal-type reactions after needle removal, there were 359 DRs and 93 falls. Elderly donors and female donors with syncopal-type reactions had a significantly higher risk of DRs (P for trend < 0·001). Elderly donors with syncopal-type reactions also had a higher risk of falls (P for trend < 0·001). Among all donors with syncopal-type reactions, the risk of DRs or falls was not correlated with EBV, BMI or donation frequency. CONCLUSION: In female donors and elderly donors (donating 400 ml of WB), syncopal-type reactions tended to be delayed. Elderly donors with syncopal-type reactions had a significantly higher risk of falls.

Blood Donor Deferral among Students in Northern Japan: Challenges Ahead.

BACKGROUND: As Japan's aging society needs more blood, young students comprise a progressively smaller portion of the donor pool. To ensure a safe and sustainable blood supply, it is crucial to select suitable donors. This study aims to evaluate donor deferral rates, causes of deferral, and characteristics of deferred Japanese students. METHODS: Computerized records of blood centers in northern Japan (Miyagi and Fukushima Prefectures) from March 2010 through March 2011 were retrospectively analyzed. RESULTS: Among 231,361 individuals visiting during the 12-month period, 24,778 were students. Of these, 19,193 (77%) attempted donation, and 5,585 (23%) were deferred. Low hemoglobin, questionnaire-based interview decisions, and medication were the main reasons for temporary deferral. Age, sex, and blood center location were associated with low hemoglobin; donation history and blood center location were associated with medication-based deferral. The odds ratio among female students deferred for low hemoglobin was 35.48 with a 95% CI of 27.74-45.38. CONCLUSIONS: These results suggest that continued efforts are needed to motivate deferred potential donors to return, to prevent low hemoglobin especially among females, and to review medical interview decisions, while paying close attention to regional differences.

Comparative in vitro evaluation of apheresis platelets stored with 100% plasma versus bicarbonated Ringer's solution with less than 5% plasma.

BACKGROUND: The major strategy for reducing the frequency of adverse reactions to platelet (PLT) transfusions is PLT washing with PLT additive solutions (PASs). In Japan, a mixture of medical infusion solutions such as acetate Ringer's solution, sodium bicarbonate, magnesium sulfate, and ACD-A is currently used as a PAS because none of the common types of PASs are officially permitted for clinical use. Recently, a bicarbonated Ringer's solution (BRS) was developed using bicarbonate as an alkaline agent. The aim of this study was to evaluate whether a BRS can effectively be utilized as a PAS for clinical use. STUDY DESIGN AND METHODS: The washing and storage solution was prepared by adding 25 mL ACD-A to 500 mL of BRS (BRS-A), consisting of 95.2 mmol/L NaCl, 3.8 mmol/L KCl, 0.9 mmol/L MgCl2 ,1.4 mmol/L CaCl2 , 26.6 mmol/L NaHCO3 , 5.8 mmol/L glucose, 4.2 mmol/L trisodium citrate, and 1.8 mmol/L citric acid. The in vitro properties of apheresis PLTs suspended in BRS-A with low concentration of plasma (<5%) were compared with those suspended in 100% plasma during 7-day storage. RESULTS: The in vitro properties of pH, hypotonic shock response, glucose consumption rate, lactate production rate, swirling, CD62P, and CD42b expression in PLTs suspended in BRS-A were comparable or superior to those suspended in 100% plasma during 7-day storage. CONCLUSION: BRS-A, prepared by mixing the only two solutions permitted for clinical use in Japan, has a positive capability to maintain PLT function. These results indicate that PLT washing and storage with BRS-A is feasible.

Analysis of blood donor deferral in Japan: characteristics and reasons.

BACKGROUND AND OBJECTIVES: To ensure an adequate and safe blood supply, it is crucial to select suitable donors according to stringent eligibility criteria. This study aims to evaluate donor deferral rates, causes of deferral, and characteristics of deferred Japanese donors. MATERIALS AND METHODS: Computerized records of blood centers in Miyagi and Fukushima Prefectures from March 2010 through March 2011 were retrospectively analyzed. RESULTS: Among 231,361 individuals presenting during this period, 186,513 had complete data. Of these 160,763 (86%) attempted donation and 25,750 (14%) were deferred. The overall proportion of deferrals was higher among those less than 20 years old (24% vs 13%, P<0.0001), female (26% vs 7%, P<0.0001), and first-time donors (28% vs 12%, P<0.0001). Factors that were significantly associated with deferral status were female sex [Odds ratio (OR)=4.40], first-time donation attempt (OR=2.42), and donation at Fukushima blood centers (OR=0.57). Main reasons for temporary deferral were low hemoglobin and questionnaire-based interview decisions. CONCLUSIONS: First-time and female were more frequently deferred whereas those presented at Fukushima blood centers were less frequently deferred. Low hemoglobin was the major contributor for female donors. Strategies to minimize deferral are needed to ensure an adequate and safe blood supply.

Successful surgical management of patients with infective endocarditis associated with acute neurologic deficits.

Subjects were 2 patients with neurologic deficits due to infective endocarditis. The first, a 30-year-old woman with acute ischemic stroke, was found to have vegetation from infective endocarditis as the embolic source. Two weeks after she experienced an acute ischemic stroke, we conducted elective cardiac surgery. The second, a 16-year-old girl with infective endocarditis, suffered a ruptured mycotic aneurysm in the left carotid system complicated by intracranial hemorrhage. We conducted a successful staged mitral valve replacement following craniotomy.

Surgical repair for tracheo-innominate artery fistula with a muscle flap.

A 70-year-old woman was quickly diagnosed as having tracheo-innominate artery fistula by three-dimensional computed tomography. Immediate surgical exploration was performed to control the bleeding using a temporary shunt. After the damaged artery was excised, vascular reconstruction was performed to preserve the connection between the proximal and distal ends of the innominate artery with the interposition of a saphenous vein graft. A pedicled sternocleidomastoid muscle flap was successfully used for the tracheal reconstruction.

Preoperative MDCT evaluation of the artery of Adamkiewicz and its origin.

OBJECTIVE: To assess the usefulness of MDCT in the preoperative evaluation of the artery of Adamkiewicz (ARM) and its parent artery. METHODS: Ten patients with thoracoabdominal vascular diseases underwent MDCT of the entire aorta and iliac arteries. The visualization of the ARM, and its branching level and site of origin, and the continuity of the intercostal/lumbar arteries with the ARM were investigated. RESULTS: In 9 of the 10 patients, the ARM was clearly visualized. The entire length from the intercostal/lumbar arteries to the ARM could be traced in 8 of the 10 patients. Surgical treatment or stentgraft insertion was based on a consideration of the vascular supply to the ARM. No postoperative ischemic spinal complications occurred. CONCLUSIONS: MDCT permits the evaluation of the ARM for its entire length and provides information on the intercostal and lumbar arteries and entire aorta.

Demonstration of the artery of Adamkiewicz at multi- detector row helical CT.

PURPOSE: To assess the ability of multi-detector row helical computed tomography (CT) to depict the artery of Adamkiewicz. MATERIALS AND METHODS: Seventy patients with vascular diseases underwent multi-detector row helical CT of the entire aorta and iliac arteries. The artery of Adamkiewicz was examined on multiplanar and curved planar reformation images and on cine-mode displays. The visualization of the artery of Adamkiewicz, as well as its branching level and side of origin, was investigated. RESULTS: In 63 (90%) of the 70 patients, at least a single artery of Adamkiewicz was clearly visualized from the intervertebral foramen to the hairpin-shaped union with the anterior spinal artery. Two arteries of Adamkiewicz were identified in 15 (24%) of 63 patients. Fifty-five arteries of Adamkiewicz (71%) originated from the left side. Seventy-two (92%) originated between T8 and L1. Neither the intercostal vein nor the posterior spinal vein were visualized in 57 of 63 patients. Continuity of the entire length, starting from the stem of the intercostal or lumbar artery and proceeding to the artery of Adamkiewicz and finally to the anterior spinal artery, was traceable on cine-mode displays or on curved planar reformation images in 20 of 63 patients. CONCLUSION: Multi-detector row helical CT depicts the artery of Adamkiewicz in a high percentage of patients.