Wim de Kort

Effects of skin disinfection method, deviation bag, and bacterial screening on clinical safety of platelet transfusions in the Netherlands

BACKGROUND:  Bacterial contamination of blood products is a great hazard for development of fatal transfusion reactions. Bacterial screening of platelet concentrates (PC) by aerobic and anaerobic culturing (BacT/ALERT, bioMérieux) was introduced in the Netherlands in October 2001.

Exploring the pattern of blood donor beliefs in first-time, novice, and experienced donors: differentiating reluctant altruism, pure altruism, impure altruism, and warm glow

BACKGROUND: Using constructs from the Theory of Planned Behavior and theories of altruism, this article explores how multiple motivations and beliefs for blood donation are clustered and change across the donor career. In so doing important distinctions, for blood donation, between impure altruism, pure altruism, and warm glow are explored.

Platelet ADP response deteriorates in synthetic storage media

BACKGROUND:  During storage under blood bank conditions, platelets (PLTs) are known to secrete ADP. PLT stimulation by ADP results in refractoriness to restimulation, making this response one of the most unstable PLT reactions. The goal of this study was to evaluate the ADP‐induced responses of PLTs stored in full plasma or in plasma and additive solution (AS).

Exploring the dynamics of the theory of planned behavior in the context of blood donation: does donation experience make a difference?

BACKGROUND: This study investigates the influence of different variables from the theory of planned behavior (TPB) on intention within multiple donation categories, covering the entire range of lifetime number of donations (LND). Does the same set of variables predict intention equally strong throughout the donor career?

High prevalence of subclinical iron deficiency in whole blood donors not deferred for low hemoglobin

Blood donors that meet the hemoglobin (Hb) criteria for donation may have undetected subclinical iron deficiency. The aim of this study was to assess the prevalence of subclinical iron deficiency in whole blood donors with Hb levels above cutoff levels for donation by measuring zinc protoporphyrin (ZPP) levels. In addition, prevalence rates based on other iron variables were assessed for comparison.

Adverse reactions, psychological factors, and their effect on donor retention in men and women

BACKGROUND: This study investigates the effect of a vasovagal reaction (VVR) or needle reaction (NR) on the risk of stopping as a blood donor, taking into account variables from the Theory of Planned Behavior (TPB). Is stopping risk solely related to the adverse reaction itself, or do the TPB variables play a role as well? Emphasis is placed on possible sex differences.

Hemoglobin Level Is Positively Associated With Blood Pressure in a Large Cohort of Healthy Individuals

It has been hypothesized that an increased hemoglobin level elevates blood pressure. The present study investigated the association between hemoglobin level and systolic blood pressure and diastolic blood pressure in healthy persons. The study population was composed of 101 377 whole blood and plasma donors, who made 691 107 visits to the blood bank. At each visit, hemoglobin level and blood pressure were measured as part of the standard procedure before a blood donation. We used repeated measurement analysis to analyze the data. We used generalized estimating equation models to assess the between-person effect and linear mixed models to assess the within-person effect. All of the analyses were done separately for men and women. In the study population, 50% were men. The mean age in men was 49.3 years (±12.5 years), and in women it was 42.4 years (±13.7 years). Hemoglobin level was positively associated with both systolic and diastolic blood pressures. With respect to the between-person effect, regression coefficients for systolic blood pressure were 1.3 mm Hg per millimole per liter increase in hemoglobin level for men and 1.8 mm Hg per millimole per liter increase in hemoglobin level for women. With respect to the within-person effect, regression coefficients for systolic blood pressure were 0.7 mm Hg and 0.9 mm Hg per millimole per liter increase in hemoglobin level, for men and women, respectively. For diastolic blood pressure, results were comparable. The results show that hemoglobin level is positively associated with both systolic and diastolic blood pressures in healthy individuals. We observed consistent effects between persons but also within persons.

Development and validation of a prediction model for low hemoglobin deferral in a large cohort of whole blood donors

BACKGROUND: Each year, approximately 5% of the invited blood donors is eventually deferred from donation because of low hemoglobin (Hb) levels. Estimating the risk of Hb deferral in blood donors can be helpful in the management of the donation program. We developed and validated a prediction model for Hb deferral in whole blood donors, separately for men and women.

Unexpected predictor–outcome associations in clinical prediction research: causes and solutions

Clinical prediction models aim to predict individual clinical outcomes using multiple predictor variables. Prediction models are abundant in the medical literature and their number is increasing.[1][1]–[3][2] Established causal risk factors are often good predictors. For example, the Framingham

Platelet pool inventory management: theory meets practice

BACKGROUND: The shelf life of platelet concentrates (PCs) is a matter of days. Simultaneously, the demand is highly variable, shortages are not allowed, and producing too many results in outdating. Concurrently, younger PCs, implying an extended time till outdating (TTO), are preferred. Common PC inventory management relies on experience‐based order‐up‐to rules. This study aimed at minimizing outdating and shortages, while extending the TTO through a theoretical approach. It focuses on PCs processed from whole blood donations.