Vox Sanguinis最新文献

Background and objectives: Canadian Blood Services defers donors during and for 4 months after oral pre-exposure or post-exposure prophylaxis (PrEP/PEP) for human immunodeficiency virus (HIV) because of concerns about altered viral kinetics. We assessed the impact of the switch from a time-based deferral for men who have sex with men (MSM) to sexual risk behaviour criteria on PrEP/PEP deferrals.

Materials and methods: Data on PrEP/PEP deferral codes were extracted from our National Epidemiology Database for the 22 months before (Period 1) and after (Period 2) the criteria change.

Results: PEP deferrals remained stable (2.3 vs. 1.7 per 100,000 donations in Periods 1 and 2, p = 0.2892), about 45% and 33%, respectively, of these donors who reported a recent needle stick injury. PrEP deferrals increased from 5.9 to 12.4 per 100,000 (p = 0.0001); approximately 30% of donors in both periods had other HIV risk factor deferrals. Donors deferred for PrEP use alone were more likely to be male, first-time users and younger than other donors.

Conclusion: The switch to sexual risk behaviour led to a small increase in deferrals for PrEP. We may not be measuring the full impact of deferral criteria because potential donors may self-defer and PrEP use is increasing.

Background and objectives: In the setting of tissue hypoxia, S-nitrosylated haemoglobin (SNO-Hb) plays crucial roles in the control of blood flow. This is associated with decreased oxygen affinity to haemoglobin and increase in tissue oxygenation. Red blood cell (RBC) transfusion is primarily performed to improve tissue oxygenation in anaemic patients. RBCs after storage undergo a variety of biochemical and functional alterations, including deficiency of nitric oxide (NO) bioactivity. However, how donor characteristics affect NO levels during RBC storage is unclear. We sought to investigate the association of blood donor age, gender and storage duration with NO and SNO-Hb levels in blood units.

Materials and methods: Blood samples from 42 healthy younger (≤30 years) and older (≥45 years) donors were collected and stored for up to 42 days. Total NO kits were used to detect total nitrite and nitrate levels in blood storage solution. SNO-Hb levels in RBCs were detected and analysed by quantitative mass spectrometry.

Results: Total NO levels in the blood storage solution significantly increased with donor age and storage duration. Proteomic analysis revealed that RBCs from older donors, particularly older females, significantly lost SNO-Hb during storage. Our findings indicate that RBCs from older donors are associated with reduced SNO-Hb levels and increased NO metabolites in storage solution after ≥35 days storage.

Conclusion: The findings suggest stored RBCs from older donors may have reduced capacity to deliver oxygen to tissues under hypoxia. A shorter shelf life may be required for storing RBCs from older donors, particularly older females.

Background and objectives: Anaemia is a treatable common condition with various aetiologies and is prevalent in hospitalized patients. However, anaemia is inconsistently worked up and treated in the inpatient setting, in part because there is no standardized inpatient diagnostic and treatment approach to anaemia. Therefore, the objective of this study was to examine the diagnostic approach and prevalence of common aetiologies of anaemia in hospitalized patients and test for an association between aetiologies of anaemia and patient characteristics.

Materials and methods: This study is a prospective observational study of hospitalized adult patients with anaemia. Patient laboratory data were used to assess the frequency of anaemia diagnostic workup and common aetiologies of anaemia.

Results: In a sample of 945 patients (mean age 58 years, 57% female and 72% Black), 30% patients had chronic anaemia, 11% had multifactorial anaemia, 5% had iron deficiency and 37% had insufficient laboratory data to determine their anaemia aetiology (unidentified aetiology). Patients with an unidentified aetiology received fewer transfusions and were more likely to be White, have longer hospital stays and have higher nadir haemoglobin levels.

Conclusion: A significant portion of hospitalized patients with anaemia did not have an identified aetiology. A standardized diagnostic algorithm could decrease this number and help patients receive appropriate treatment.

Background and objectives: In the setting of trauma and suspected critical bleeding, indications to commence blood transfusions remain unclear, with high rates of potentially avoidable transfusions. Prehospital blood lactate measurements could help predict the need for blood transfusions. The aim of this study was to compare measurements detected by a point-of-care (POC) lactate device with laboratory measured lactate levels.

Materials and methods: This was a cross-sectional study conducted in the emergency department. Eligible patients were those with suspected major trauma and critical bleeding. Venous or arterial blood samples were collected. POC measurements of lactate levels were conducted using a StatStrip Xpress® lactate meter and compared with laboratory values.

Results: Among 70 patients, the mean difference between the POC and laboratory lactate results was -0.19 mmol/L, with limits of agreement at -1.9 and 1.5. Most measurements (n = 66; 94.3%) were within the limits of agreement. A POC lactate level of >3.3 mmol/L had >90% specificity for transfusion, whereas a level <1.4 mmol/L had 90% sensitivity to rule out a transfusion.

Conclusion: The level of agreement of POC lactate with the laboratory lactate was high. Research on clinical decision rules for pre-hospital transfusion that incorporate POC lactate measures is therefore feasible.

Background and objectives: Routine coagulation screens at birth are still standard in some European neonatal intensive care units (NICUs), although interpretation of these results is complex in preterm infants. It is unclear to what extent local coagulation assay results agree with published reference ranges when using different analysers and reagents. We aimed to assess coagulation assay results on day 1 of life in very preterm infants admitted to the NICU.

Materials and methods: We included all preterm infants born below 32 weeks gestational age (GA) admitted to the Leiden University Medical Center between 2004 and 2020 in whom coagulation assays (prothrombin time [PT] and activated partial thromboplastin time [APTT]) were obtained during the first 24 h of life. Infants either diagnosed with major intraventricular haemorrhage or who received plasma transfusion before coagulation assay were excluded. We assessed coagulation assay results and compared the results between <28 weeks (extremely preterm) and 28-32 weeks (very preterm) GA groups.

Results: Coagulation assays were obtained at birth in 144 infants (144/2577; 5.5%) of whom 104 fulfilled the inclusion criteria. We found similar median PT and APTT values for extremely and very preterm infants (PT: 18.1 vs. 18.7 s [p-value = 0.400]; APTT: 44.2 vs. 47.7 s [p-value = 0.252], respectively).

Conclusion: We found similar coagulation assay results at birth for extremely and very preterm infants; however, results deviated considerably from some of the published reference ranges. This may be due to differences between analysers and reagents, underlining the need for reference ranges calibrated to the equipment used per NICU.

Background and objectives: Wrong blood in tube (WBIT) continues to be a preventable cause of unintended harm to the patient. The literature describing extent of the problem, its consequences and factors leading to WBIT from the perspective of lower middle-income countries (LMICs) is limited. The present study describes WBIT and its outcome in a hospital-based blood centre from an LMIC.

Materials and methods: WBIT events occurring during the study period were analysed to identify the root cause. In addition, they were analysed according to discipline, department and time of sample draw. Root causes were divided and compared with standard operating procedure (SOP) for sample collection for blood requests. All WBIT events were followed and their outcomes analysed.

Results: WBIT events occurred at a rate of 4.8/10,000 blood requests, with a higher rate in urgent requests (5.2/10,000 requests). The average rate of WBIT was higher in surgical disciplines compared to medical and acute care services (6.58 vs. 4.43 vs. 3/10,000 requests). The highest rate of WBIT was observed when requests were received during 8:00 PM-2:00 AM (p = 0.02). Deviations from SOP with contribution from human and organizational elements were identified as the root cause. The consequences ranged from delay in providing blood to acute haemolytic transfusion reactions.

Conclusion: We found that WBITs occurred at a rate comparable to that reported from developed countries. Use of software and automation may reduce the rate of WBIT but not eliminate it completely. Strict adherence to SOPs and continuous training of phlebotomy staff would help reduce it to a minimum. Blood centres need to develop specific strategies with respect to their root causes.