International Council for Standardization in Haematology (ICSH) recommendations for processing of blood samples for coagulation testing

This guidance document has been prepared on behalf of the International Council for Standardization in Haematology (ICSH). The aim of the document is to provide guidance and recommendations for the processing of citrated blood samples for coagulation tests in clinical laboratories in all regions of the world. The following areas are included in this document: Sample transport including use of pneumatic tubes systems; clots in citrated samples; centrifugation; primary tube storage and stability; interfering substances including haemolysis, icterus and lipaemia; secondary aliquots—transport, storage and processing; preanalytical variables for platelet function testing. The following areas are excluded from this document, but are included in an associated ICSH document addressing collection of samples for coagulation tests in clinical laboratories; ordering tests; sample collection tube and anticoagulant; preparation of the patient; sample collection device; venous stasis before sample collection; order of draw when different sample types are collected; sample labelling; blood-to-anticoagulant ratio (tube filling); influence of haematocrit. The recommendations are based on published data in peer-reviewed literature and expert opinion.     

Everyday technology use among older adults in Sweden and Portugal

Abstract

Background: Technology use is relevant for engaging in everyday occupations and aging in place and difficulties might limit participation.

Aim: The aim of the present study was two-fold: to investigate the internal scale validity of the Everyday Technology Use Questionnaire (ETUQ) in a matched Portuguese and a Swedish sample of older adults without known cognitive impairments and to compare everyday technology use (i.e., the relevance of Everyday Technology (ET) and perceived difficulty of using ET).

Methods: The Rasch rating scale model was used to investigate the psychometric properties of the data from the two countries. Analyses were then used to compare the samples.

Results: There is evidence of internal scale and person response validity in the Swedish and Portuguese ETUQ datasets. The Swedish sample demonstrated almost 25% more ETs to be relevant, as compared to the Portuguese sample (p?<?.05). The samples’ means of perceived difficulty in using ETs were similar.

Conclusions: The results support that the ETUQ is a valid assessment for measuring the relevance of and perceived difficulty of ET use and is able to detect differences and similarities between older adults in these European countries in relation to ET use in the home and society.     

Interpretation and management of INR results: A case history based survey in 13 countries

Introduction

Standardisation of treatment with vitamin K antagonists (VKAs) is still an issue after 60 years of use. The study aimed to explore aspects of VKA monitoring in primary and secondary care.

Methods

Two case histories were distributed to physicians in 13 countries. Case history A focused on a patient with atrial fibrillation on stable anticoagulation (latest INR 2.3). Physicians were asked about frequency of INR measurement, when to change the VKA dose, and the patient's annual risk of ischemic stroke and bleeding. Case history B focused on a patient with an unexpected INR of 4.8, asking for the patient's 48-hour bleeding risk, the immediate dose reduction and time until a repeat INR.

Results

Altogether, 3016 physicians responded (response rate 8 - 38%), of which 82% were from primary care and 18% from secondary care. Answers varied substantially within and between countries regardless of level of care and VKA used. Median number of weeks between INR measurements was 4 - 6 weeks. Median threshold INR for increasing or decreasing the VKA dose was 1.9 and 3.1, respectively. Risk of ischemic stroke and bleeding were overestimated 2 - 3 times. In case history B, the median dose reduction the two first days was 75% for GPs and 55% for specialists, irrespective of estimates of bleeding risk; with one week to a repeat INR.

Conclusion

Variation in VKA monitoring is substantial implying clinical consequences. Guidelines seem either unknown or may be considered impracticable. Further efforts towards standardisation of VKA management are needed.     

P-drive: assessment of driving performance after stroke.

OBJECTIVE: To investigate aspects of validity and stability of Performance Analysis of Driving Ability (P-Drive), for people with stroke when used in a driving simulator. DESIGN: A cross-sectional observational study. SUBJECTS: The study included a consecutive series of 101 participants with stroke referred for evaluation or selected from a stroke registry. METHODS: P-Drive was used to observe driving performance in order to assess driving ability. P-Drive comprises 20 items assessing the quality of the participant's driving performance. Aspects of validity and reliability in P-Drive were evaluated using Rasch statistics. RESULTS: The items (95%) and participants (97%) demonstrated acceptable goodness-of-fit and met statistical expectations according to the Rasch model. The results support internal scale validity and person response validity. P-Drive could separate the participants with different driving abilities and the standard errors were within reasonable criteria for drivers with a moderate-to-low ability to drive. CONCLUSION: The findings from this study indicated that P-Drive is an assessment tool with properties of internal scale validity, person response validity, and which also contains aspects of reliability in relation to precision of the estimates and separation. P-Drive seems to be a valid and stable assessment tool for assessing the driving ability in a simulator of people with stroke.     

Postanalytical external quality assessment of warfarin monitoring in primary healthcare

BACKGROUND: An increasing number of patients are treated with warfarin worldwide, and many are monitored in general practice, often with office instruments. Bleeding or thromboembolic episodes may be consequences of inadequate treatment. We have therefore examined some important aspects of general practitioners' (GPs') knowledge of warfarin treatment. METHODS: A questionnaire including 2 case histories with familiar indications for warfarin treatment (mechanical heart valve prosthesis and pulmonary embolism) was circulated to 3781 GPs in Norway as a postanalytical quality assessment. RESULTS: A total of 1547 GPs (41%) responded. There were substantial variations among GPs concerning the frequency of international normalized ratio (INR) monitoring, stated therapeutic ranges for arterial (but not venous) indications for anticoagulation therapy, and handling of a moderately high INR result of 5.9. Most GPs estimated an unrealistically high risk of serious bleeding in the latter situation (median, 15%; 10th and 90th percentiles, 4% and 50%, respectively). The critical difference necessary to change the warfarin dose was highly dependent on perceived therapeutic intervals, and about half of the GPs suggested a critical difference of 0.8 INR, which is attainable with office instruments. Sex and age of the GPs, practice size, and availability of an INR instrument in the office laboratory did not influence the results to any substantial degree, as variations within subgroups were similar. CONCLUSIONS: Gross variations in practice were found, especially for aspects of warfarin treatment that lacked uniform guidelines. Evidence-based and practicable recommendations for treatment and monitoring of these patients are still needed.     

Negative energy balance in male and female rangers: effects of 7 d of sustained exercise and food deprivation

BACKGROUND: A challenging 7-d ranger field exercise (FEX) by cadets in the Norwegian Military Academy provided a venue in which to study the effects of negative energy balance. OBJECTIVE: We quantified total energy expenditure (TEE), food intake, and changes in body composition in male and female cadets. DESIGN: TEE (measured by doubly labeled water), food intake, activity patterns (measured by accelerometry), and body composition (measured by dual-energy X-ray absorptiometry) were measured in 16 cadets (10 men and 6 women aged 21-27 y). RESULTS: The physically active (approximately 23 h/d) and semistarved (0.2-2.2 MJ/d) cadets lost weight (x +/- SD: men, -7.7 +/- 1.1 kg; women, -5.9 +/- 1.1 kg; P < 0.05). Absolute TEE differed by sex (men, 26.6 +/- 2.0 MJ/d; women, 21.9 +/- 2.0 MJ/d; P < 0.05) but body weight-specific TEE did not (men, 343 +/- 26 kJ . kg(-1) . d(-1); women, 354 +/- 18 kJ . kg(-1) . d(-1); NS). Fat-free mass (FFM) loss differed significantly by sex (men, -4.0 +/- 1.2 kg; women, -2.5 +/- 1.1 kg; P < 0.05), but percentage FFM loss did not (men, -6.3 +/- 1.9%; women, -5.6 +/- 2.4%). In contrast, absolute FM loss did not differ significantly by sex (men, -3.45 +/- 0.72 kg; women, -3.42 +/- 0.22 kg), but fat oxidation (men, 5.2 +/- 1.0 mg . min(-1) . kg FFM(-1); women, 7.3 +/- 0.5 mg . min(-1) . kg FFM(-1)) and the relative contribution of FM to TEE (men, 74 +/- 14%; women, 89 +/- 6%) were significantly greater in women than in men (P < 0.05). CONCLUSION: Female cadets maintained a significantly more fat-predominant fuel metabolism than did male cadets in response to sustained exercise and semistarvation.     

Endocrinology: Human chorionic gonadotrophin self-administered by the subcutaneous route to induce oocyte maturation in an in-vitro fertilization and embryo transfer programme

This study was initiated to evaluate oocyte maturation and theoutcome of in-vitro fertilization (IVF) cycles following thes.c. administration of human chorionic gonadotrophin (HCG) bythe patient herself or her partner. A group of 104 women whoentered our IVF embryo transfer programme were prospectivelyrandomized to have 5000 IU or 10 000 IU HCG s.c. or i.m. TheHCG was administered for induction of the final oocyte maturationin cycles with pituitary down-regulation with a gonadotrophin-releasinghormone agonist according to a long protocol and where ovarianstimulation had been achieved with pure follicle stimulatinghormone. The mean concentration of HCG in serum 12 and 36 hafter the HCG injection was significantly higher in the womenreceiving 5000 IU i.m. compared to the s.c. route. However,in women receiving 10 000 IU HCG there were no significant differencesin the mean concentrations 12 and 36 h after the injection,irrespective of the route of administration. Furthermore, therewere no significant differences in the relative numbers of retrievedmature oocytes between the groups. When comparing the clinicaloutcome in the different groups, no significant differenceswere found between those receiving 5000 IU or 10 000 IU HCG,i.m. or s.c. Our data indicate that HCG can be given s.c. withoutreducing the chance of retrieving a mature oocyte and that theclinical outcome with regard to pregnancies is not negativelyaffected.