Invited commentary: “Identifying traumatic significant haemorrhage is challenging for patient with low and intermediate risk, not when bleeding is obvious”

Abstract

We would like to thank the authors for their valuable comments on our study, wherein we investigated how pre-hospital lactate (P-LACT) measurements could be used to predict the need for (ongoing) in-hospital blood product transfusion in patients attended by HEMS with major traumatic haemorrhage.

As mentioned in our article, the algorithm we developed is a decision support tool, which means that it should be used in conjunction with other parameters, such as clinical gestalt in a heuristic approach to estimate transfusion requirements. The cut-off value of a P-LACT < 2.5 mmol/l used in our population yielded a sensitivity of 80% (corresponding to a low probability of major haemorrhage as the authors rightly mention), and hence was inadequate to be used in isolation. The SOP in our service states that a P-LACT < 2.5 mmol/l is used in conjunction with an SBP > 100mmHg to identify patients who have a low probability of major hemorrhage. This is supported by a recent publication of Gaessler et al. (2023) wherein the authors show that P-LACT and SBP are complimentary in terms of predictive probability [1].

To identify patients with a high likelihood of major haemorrhage requiring in-hospital transfusion, a P-LACT of 6.0 mmol/l was used, as at this this point the predicted probability curve (Fig. 2 in our original article) starts to flatten: using a higher cut-off would not have yielded a higher specificity, whereas a lower cut-off would have dropped specificity whilst not yielding a much higher proportion of the population meeting the cut-off criteria (n = 13, 6.7% for a lactate of 6.0 mmol/l vs. n = 17, 8.7% for a lactate of 5.5 mmol/l). Although we agree that it is likely that many patients with a lactate > 6.0 mmol/l will show clinical signs of shock, 5/13 patients had an SBP > 100 mmHg on first occasion, two of whom also did not exhibit tachycardia. In these patients P-LACT may still be a useful tool. Despite this however, the major challenge remains to identify the bleeding patients in the P-LACT group of 2.5-6 mmol/l, and serial measurements may be the way forward in this group.

Finally, we acknowledge that transfusion requirement is not always a good surrogate to use for outcome, especially not when confounding by indication may be present: using lactate may result in transfusing more patients in the pre-hospital setting, which again may result in a lower threshold to continue transfusion in-hospital. However, as 2/3 of the patients in our cohort received a massive transfusion (> 10 units PRBC within 24 h) rather than a major transfusion, we think transfusion requirement was a reasonable surrogate for risk of death from bleeding in our population. We agree however, that ideally outcome studies should be performed using hard endpoints to confirm this.

Not applicable.

1. Gaessler H, Helm M, Kulla M, et al. Prehospital predictors of the need for transfusion in patients with major trauma. Eur J Trauma Emerg Surg. 2023;49:803–12.

   Article PubMed Google Scholar

Download references

None.

No external funding was received for this study.

Authors and Affiliations

1. Air Ambulance Charity Kent Surrey Sussex, Hanger 10 Redhill Aerodrome, Redhill, RH1 5YP, UK

   Joanne E Griggs, Richard M Lyon, Gary Wareham & Ewoud Ter Avest

2. School of Health Sciences, University of Surrey, Priestley Rd, Guildford, GU2 7YH, UK

   Joanne E Griggs & Richard M Lyon

3. Bristol Dental School, Faculty of Health Sciences, University of Bristol, Child Dental Health, Lower Maudlin Street, Bristol, BS1 2LY, UK

   Martyn Sherriff

4. South East Coast Ambulance NHS Foundation Trust, Neptune House, Gatwick, RH10 9BG, Surrey, UK

   Jack W Barrett

5. Department of Emergency Medicine, University Medical Center Groningen, Groningen, The Netherlands

   Ewoud Ter Avest

Authors

1. Joanne E GriggsView author publications

   You can also search for this author in PubMed Google Scholar

2. Richard M LyonView author publications

   You can also search for this author in PubMed Google Scholar

3. Martyn SherriffView author publications

   You can also search for this author in PubMed Google Scholar

4. Jack W BarrettView author publications

   You can also search for this author in PubMed Google Scholar

5. Gary WarehamView author publications

   You can also search for this author in PubMed Google Scholar

6. Ewoud Ter AvestView author publications

   You can also search for this author in PubMed Google Scholar

Contributions

JG/EtA initiated the original project. EtA drafted the comment. All authors read and approved the final version.

Corresponding author

Correspondence to Joanne E Griggs.

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

None.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and Permissions

Cite this article

Griggs, J.E., Lyon, R.M., Sherriff, M. et al. Invited commentary: “Identifying traumatic significant haemorrhage is challenging for patient with low and intermediate risk, not when bleeding is obvious”. Scand J Trauma Resusc Emerg Med 31, 98 (2023). https://doi.org/10.1186/s13049-023-01162-1

Download citation

• Received: 26 November 2023

• Accepted: 27 November 2023

• Published: 12 December 2023

• DOI: https://doi.org/10.1186/s13049-023-01162-1

Share this article

Anyone you share the following link with will be able to read this content:

Get shareable link

Sorry, a shareable link is not currently available for this article.

Copy to clipboard

Provided by the Springer Nature SharedIt content-sharing initiative