A case of severe pseudohyperkalaemia due to muscle contraction

Introduction: Severe hyperkalaemia is a serious medical condition requiring immediate medical attention. Before medical treatment is started, pseudohyperkalaemia has to be ruled out. Case description: A 10-month old infant presented to the emergency department with fever and coughing since 1 week. Routine venous blood testing revealed a severe hyperkalaemia of 6.9 mmol/L without any indication of haemolysis. Reanalysis of the plasma sample confirmed the hyperkalaemia (7.1 mmol/L). Based on these results, the clinical pathologist suggested to perform a venous blood gas analysis and electrocardiogram (ECG) which revealed a normal potassium of 3.7 mmol/L and normal ECG, ruling out a potentially life-treating hyperkalaemia. The child was diagnosed with pneumonia. The paediatrician had difficulty to perform the first venous blood collection due to excessive movement of the infant during venipuncture. The muscle contractions of the child in combination with venous stasis most probably led to a local increase of potassium in the sampled limbs. The second sample collected under optimal preanalytical circumstances had a normal potassium. Since muscle contraction typically does not cause severe hyperkalaemia, other causes of pseudohyperkalaemia were excluded. K3-EDTA contamination and familial hyperkalaemia were ruled out and the patient did not have extreme leucocytosis or thrombocytosis. By exclusion a diagnosis of pseudohyperkalaemia due to intense muscle movement and venous stasis was made. Conclusion: This case suggests that intense muscle contraction and venous stasis can cause severe pseudohyperkalemia without hemolysis. Once true hyperkalemia has been ruled out, a laboratory work-up can help identify the cause of pseudohyperkalaemia

Analyzing human factors in road accidents: TRACE WP5 Summary Report

The main objectives of TRACE WP5 'Human factors' deliverables are: i) To support a better standardization of accident analysis in Europe on a scientific background, ii) To provide operational models and methodological classification grids dealing with 'human factors' aspects involved in road accidents, iii) To promote a comprehensive analysis of the involvement of human beings, going further than the usual 'user-orientated causal analysis' often limited at establishing the driver 'at fault' and without searching for the background reasons of the problems met par road users. Such objectives involve analyzing accidents as the symptom of the difficulties met by drivers in certain driving situations, and as a revelatory of their needs in help. Two questions have to be asked in order to progress in the understanding of accident causation: 1) What are precisely and operationally the human failures in accidents? But also: 2) What are the reasons for these human failures? Keeping in mind that these reasons are of multiple natures and combine most of the time to produce the final event. By so doing, the definition of typical scenarios of 'human error' production can open to the definition of more appropriate countermeasures, well fitted to human needs

Which factors and situations for human functional failures? Developing grids for accident causation analysis

This report describes the work undertaken in Task 5.2 of the TRACE project. Human failures are explained by factors characterizing the state of the system and of their interactions. A grid of factors which could lead to these human functional failures is given along with a grid of pre-accident driving situations. In addition to this, an overview is included of the background work undertaken to establish a methodology for classification of these factors and situations. Factors related to the ‘User’, ‘Vehicle’ and ‘Environment’ are described and classifications for use at a ‘descriptive’, ‘generic’ and ‘in-depth’ level are determined, to allow analysis at different levels of detail of accident data. These factors and situations will be used along with the Task 5.1 functional failures to help identify typical failure generating scenarios in Task 5.3, and the subsequent analysis of real world accident data in other work packages in TRACE. They will also be a useful basis for future improvements in the collection of accident causation data, avoiding the common over simplification whereby road users are seen as the main reason for the ‘failure’ in the accident scenario

An analysis of speed related UK accidents using a human functional failure methodology

Accidents involving either illegal or inappropriate speeding play a part in a large proportion of accidents involving cars. The types of typical failure generating scenarios found in car accidents where illegal speeding or inappropriate speeding is contributory are compared using the detailed human functional failure methodology developed in the European TRACE project (TRaffic Accident Causation in Europe), funded by the European Commission. Using on-scene cases from the UK ‘On The Spot’ database (funded by the UK Department for Transport and Highways Agency), a sample of cases where speed is contributory have been analysed. An overview of speeding cases from the 4,000 in-depth cases available in the dataset is also presented. The results highlight not only the differences between inappropriate and illegal speeding cases, but also the differences in the functional failures experienced by both the ‘at fault’ and ‘not at fault’ road users in both types of speed-related accidents. The results form a unique base of knowledge for future work on the human-related issues associated with speeding of both types, for all crash participants. Also considered is how new technologies can address speeding accidents

Delayed diagnosis and treatment of extreme hypertriglyceridemia due to rejection of a lipemic sample

Most laboratories routinely determine haemolysis, icterus and lipemia indices to identify lipemic samples and reject potentially affected results. Hypertriglyceridemia is the most common cause of lipemia and severe hypertriglyceridemia (≥ 11.3 mmol/L) is a major risk factor of acute pancreatitis. A 56-year-old woman attended the outpatient clinic for a follow-up visit 1 month after a kidney transplantation. Her immunosuppressive therapy consisted of corticosteroids, cyclosporine, and mycophenolic acid. The routine clinical chemistry sample was rejected due to extreme lipemia. The comment “extreme lipemic sample” was added on the report, but the requesting physician could not be reached. The Cobas 8000 gave a technical error (absorption > 3.3) for the HIL-indices (L-index: 38.6 mmol/L) which persisted after high-speed centrifugation. The patient was given a new appointment 2 days later. The new sample was also grossly lipemic and gave the same technical error (L-index: 35.9 mmol/L). The second sample was manually diluted 20-fold after centrifugation to obtain a result for triglycerides within the measuring range (0.10–50.0 mmol/L). Triglycerides were 169.1 mmol/L, corresponding to very severe hypertriglyceridemia. This result was communicated to the nephrologist and the patient immediately recalled to the hospital. She received therapeutic plasma exchange the next day and did not develop acute pancreatitis. This case illustrates the delicate balance between avoiding the release of unreliable results due to lipemia and the risk of delayed diagnosis when results are rejected. Providing an estimate of the degree of hypertriglyceridemia might be preferable to rejecting the result

Trip related factors

WP3 of the European Project TRACE is concerned with Types of Factors to analyse the causation of road traffic accidents from a factors' point of view. In task 3.3 'Trip-related Factors' it was tried to characterise accidents that are caused by certain contributing factors found on a trip level. This was done by applying one statistical method to existing databases of the WP3 Partners on the one hand and on the other hand by performing an in-depth case analysis using the WP5 method. The analysed factors stem from the Human Component of the accident causation classification, namely "alcohol", "vigilance", and "experience", from the Vehicle Component, namely "vehicle condition/maintenance", and from the Environment component, namely "road layout" and "road condition". This selection resulted from the task 3.1 conclusions and feasibility reasons. Due to inhomogeneous results for the databases from Austria, France, Germany, Great Britain, and Spain the detailed results will be pictured in an Internal TRACE Report by Sub-reports of the WP3 Partners, in this task report the main results are discussed with respect to findings and data in other databases available to the TRACE partners as requested from WP8. Both methods applied show that trip-related factors are possible to prevent not on a trip level only, but also from a background level and as well on a level closer to the accident (driving task level). However, only some suggestions are possible to give by these results. A more detailed view for preventing the different accidents that result from trip-related factors is necessary, as shown by the results of BASt with the statistic method, as well as by INRETS with the ultra in-depth WP5 method

Driving task-related factors

Driving task-related factors by definition are ‘directly and causally contributing to the accident occurrence, very specific and detailed, are short-term lasting or dynamic in nature, and refer to the actual conditions of the components’. The aim was to analyse specific driving task-related factors to investigate how these type of factors affect the driver undertaking their tasks within driving. A selection of driving task-related factors were chosen and analysed using two types of analysis; by a statistical method and by an in-depth methodology developed in TRACE. Typical characteristics of these accidents were identified, and for a number of factors, typical failure generating scenarios were also identified. From this, a list of possible countermeasures were defined with the aim of preventing such accidents occurring. These included driver education, in-vehicle technologies and design issues. Finally, benefits and limitations of the analysis undertaken are given, with recommendation for future work on driving task-related factors

Summary report on work package 3 "Types of Factors"

This summary report presents the main results of Work Package 3 "Types of Factors" of the TRACE Project. The work as performed in the tasks 3.1 (accident related factors), 3.2 (sociological and cultural factors), 3.3 (trip-related factors), and 3.4 (driving-task associated factors) and presented in the Deliverables 3.1 to 3.4 and an additional internal TRACE Report (Collection of Sub-Reports for task 3.3) is summarized and discussed. The objective of defining relevant accident related factors first and the objective of analysing traffic accident causation - from a factor's point of view while taking traditional views into account - on different levels - by using statistic methods for existing databases as provided by the Work Package 3 Partners and - by using new (developed in Work Package 5 of the TRACE project) methods on new case analysis in order to gain new knowledge on accident causation was possible to reach. The scope of the identified key aspects as found by the Partners in their work for the relevance in EU27 is discussed. In accordance, even further, appropriate suggestions for prevention of traffic accidents can be derived