Paramedic confidence in estimating external blood loss


blood loss estimation
clinical decision making
emergency medical services
pre-hospital care

How to Cite

Harris W, Rotheram A, Pearson S, Lucas P, Edwards D, Bowerman L, Williams A-M. Paramedic confidence in estimating external blood loss. Australasian Journal of Paramedicine [Internet]. 2017Aug.7 [cited 2023May28];14(3). Available from:



Studies have identified that visual estimation of blood loss is highly inaccurate, however no research has investigated the relationship between this practice and the confidence of estimation by paramedics.

The aim of this study was to determine paramedic confidence in the estimation of, and reporting of external blood loss due to medical or trauma aetiology, within an Australasian paramedic context.


Between July and September 2015, a cross-sectional survey was distributed through Australasian paramedic professional bodies to determine confidence in estimating and documentation of external blood loss. Using Likert scale and free text responses, participants provided demographic information and their self-perceived confidence in estimating and documenting external blood loss.


Five thousand six hundred paramedics were invited to participate in an online survey. Two hundred and eight responses were received (3.8% response rate). A total of 86.6% of participants reported documenting blood loss in clinical reports, however only 47.8% of participants believed their estimation of external blood loss was accurate with 13% reporting underestimation and 33.5% reporting overestimation of blood loss. Additionally, only 51.6% of participants agreed to strongly agreed that they were confident in their estimation of blood loss.


This research demonstrates the majority of paramedics estimate and document external blood loss, yet nearly half do not feel confident in doing so, despite indicating its importance. Educational and organisational changes are recommended to reflect the clear evidence against this practice. Further research is recommended to identify appropriate physiological parameters and practical assessment tools to replace this inaccurate form of clinical assessment.


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