Preanalytical venous blood sampling practices demand improvement — A survey of test-request management, test-tube labelling and information search procedures

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Abstract

Background

Most errors in laboratory medicine are preanalytical in nature. In the present study, we aimed to survey preanalytical steps in venous blood sampling, prior to actual sample collection. These steps included test-request management and test-tube labelling, as well as information search procedures.

Methods

Venous blood sampling staff (n = 314, response rate 94%) in hospital wards and laboratories completed a questionnaire related to clinical chemistry testing.

Results

Instructions for test-request management and test-tube labelling were not always followed. For example, only 66% of the ward staff reported always checking the test-request if someone else completed it, compared to 90% of the laboratory staff (p = 0.003). As few as 16% of the ward staff reported desirable practices regarding test-tube labelling, compared to 100% of the laboratory staff (p < 0.001). Furthermore, 18% of the ward staff reported always using online manuals (the only source of updated information), compared to 63% of the laboratory staff (p < 0.001).

Conclusions

Our results indicate a substantial risk of preanalytical error in test-request management, test-tube labelling, and information search practices, particularly in the wards. Our findings thus underscore the importance of quality control in venous blood sampling, in order to increase patient safety in modern health care.

Introduction

Medical errors cause a large number of deaths annually and lead to excess economic burden [1], [2]. Laboratory tests can have a major impact on medical decisions [3], and a large number of analyses are conducted each year. However, up to 0.5% of all laboratory test-results have estimated to be erroneous [4], [5]. Of these, the majority are of preanalytical origin, occurring before the laboratory analysis [4], [5], [6], [7], [8], [9]. Thus, in order to improve patient safety, reduction of the frequency of preanalytical errors should be an important issue for all health care providers.

The majority of preanalytical errors can be related to incorrect information on the test-request or test-tube label [10], [11]. Despite the apparent importance of these sources of error, relatively little is known about how they occur, and thus what could be done to prevent them.

In modern laboratories, information about venous blood sampling (VBS) is generally provided to VBS staff through online manuals, which are much easier to update than paper-based manuals. Indeed, incomplete and/or infrequent revision of paper-based laboratory manuals has been reported [12], [13]. However, data concerning whether such on-line manuals are the primary means by which staff obtain VBS information, and if VBS is performed according to such instructions, are limited.

Clinical laboratories are often accredited [14], meaning that daily work is documented and performed according to strict routines, aimed at reducing errors. In contrast, such quality control measures are still uncommon in hospital wards. Not surprisingly, VBS performed by laboratory staff is therefore associated with fewer errors, compared to VBS performed by other personnel categories [8], [15], [16], [17], [18], [19], [20].

Research addressing the preanalytical phase of VBS has predominantly focused on quantifying the actual error rates, rather than investigating the practices potentially leading to errors. The aim of the present study was thus to investigate practical test-request management, test-tube labelling, and information search procedures with respect to VBS across all wards in two hospitals, and to compare the results with those for the VBS staff in two hospital laboratories.

Section snippets

Subjects and setting

Internationally, the staff performing VBS are varied, and can include physicians, registered nurses, enrolled nurses (also called assistant nurses, the approximate equivalent of licensed-to-practice nurses, LPNs, in North America), specific VBS staff employed by the laboratory, or other staff categories. In hospital wards in Sweden, enrolled nurses or psychiatric orderlies most often perform VBS. These staff categories also perform basic patient care, as well as other tasks such as blood

Results

The results regarding test-request management, test-tube labelling and information search procedures in the wards are presented in Table 3. In the wards, 90% of the subjects reported the DP of always comparing the patient's name and Swedish identification number with the corresponding information on the test-request. This should always be done, in order to ensure correct patient identification. Only 75% of the ward staff reported the DP of always signing the test-request. Similarly, 66%

Discussion

In this questionnaire study of preanalytical VBS practices, we aimed to investigate the steps prior to actual sample collection in the wards of two hospitals. Our findings suggest that test-requests and test-tube labels were often not handled correctly, and that information on VBS procedures was generally obtained from unreliable sources. This indicates a substantial risk of errors that should be addressed with quality control measures.

A secondary aim of the study was to compare the results for

Acknowledgements

We would like to thank: Johan Hultdin, Andreas Jonsson, Birgitta Nilsson, Birgitta Berglund, Terry Persson and Åsa Lundsten at Medical Biosciences, Umeå University; Inger Rautio, Susanna Hermansson and Ann-Britt Lindström at the Clinical Chemistry Laboratory, Umeå University Hospital; Ulf Jansson at Laboratory Medicine, Västernorrland County Council; the heads of the examined units; the enrolled nurses, psychiatric orderlies and the biomedical technicians in the units surveyed; and the enrolled

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  • Cited by (0)

    Research funding: This study was funded by the Faculty of Medicine, Umeå University, Umeå, Sweden and the National Board of Health and Welfare in Sweden.

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