Skip to content


  • Letter
  • Open Access

Variability of response to the fluid bolus is again demonstrated

Critical Care201721:224

  • Published:

The original article was published in Critical Care 2017 21:103

The AFRIM study by Obonyo et al. [1] presents haemodynamic data worthy of closer analysis. The inferior vena cava collapsability index (IVCCI) was used as a surrogate measure of intravascular volume status. However, this measurement is of limited use in spontaneously breathing patients, as demonstrated by a recent meta-analysis [2]. According to Table 1 from [1], 100% of group 1 and group 2 demonstrated chest indrawing leading to the generation of significant negative intrathoracic pressures and making the measurements invalid.

The purpose of a fluid bolus is to increase stroke volume and hence cardiac output. Although these patients were dehydrated, only 5 out of 11 in group 1 and 5 out of 9 in group 2 demonstrated a 10% increase in stroke volume following the fluid boli. Two patients in group 1 demonstrated a 10% decrease in stroke volume index, with a decrease of 48% in one case! It would interest us what the authors believe the reason for this effect is.

We believe that the administration of fluid, even in hypovolaemic patients, is more complex than often appreciated, with an interaction of many factors related to vascular biology, and further investigation is required to enable an optimisation of fluid delivery and to avoid the detrimental effects of fluid overload.

Authors’ response

  • We are encouraged by the interest in fluid resuscitation in children with severe acute malnutrition and hypovolaemic shock, and have read with keen interest the contribution by Dr. Ellis Muggleton highlighting the limited utility of IVCCI in spontaneously breathing patients.

    In the manuscript, while presenting these data [1], the authors noted the limitations in interpretation of the IVCCI, especially with respiratory distress characterised by deep (Kussmaul’s) breathing and chest indrawing. Given the limited ability of IVCCI to predict fluid responsiveness (FR), it is important to underline the fact that a single negative test with recognised limited utility cannot be used to rule out FR [2] and more research on non-invasive assessment of FR is needed as there is still emerging research advocating utility of IVCCI [3].

    Reduction in stroke volume index following fluid bolus administration is indeed an unexpected finding. Nonetheless, our findings stimulate a new direction of inquiry investigating the mechanisms underlying the pathophysiology of hypovolaemia with severe malnutrition as well as the interpretation of the patients’ relative position on the Frank-Starling curve with respect to FR. This is particularly important in the context of little understanding on the effect that fluid administration has on the complex patho-biological interaction of intravascular hypovolaemia and severe malnutrition. Previous research has shown that hypovolaemia and dehydration are associated with higher mortality in severe malnutrition [4]. The AFRIM study showed no supportive evidence of increased risk of cardiac failure in severely malnourished children receiving fluid resuscitation for hypovolaemic shock [1]. The patient with a stroke volume reduction of 48% also had an increase in the systemic vascular resistance index of 56%, which could be indicative of an advanced stage of illness with extreme physiological compensation.




    Fluid responsiveness


    Inferior vena cava collapsability index






    Availability of data and materials

    Not applicable.

    Author’s contribution

    ERM wrote the manuscript.

    Ethics approval and consent to participate

    Not applicable.

    Consent for publication

    Not applicable.

    Competing interests

    The author declares that she has no competing interests.

    Publisher’s Note

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

    Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated.

    Authors’ Affiliations

    Rotkreuzklinikum München, Nymphenburgerstrasse 63, 80634 München, Germany


    1. Obonyo N, Brent B, Olupot-Olupot P, et al. Myocardial and haemodynamic responses to two fluid regimens in African children with severe malnutrition and hypovolaemic shock (AFRIM study). Crit Care. 2017;21:103.View ArticlePubMedPubMed CentralGoogle Scholar
    2. Long E, Oakley E, Duke T, Babl FE. Does respiratory variation in inferior vena cava diameter predict fluid responsiveness: a systematic review and meta-analysis. Shock. 2017;47(5):550–9.View ArticlePubMedGoogle Scholar
    3. Corl KA, George NR, Romanoff J, Levinson AT, Chheng DB, Merchant RC, Levy MM, Napoli AM. Inferior vena cava collapsibility detects fluid responsiveness among spontaneously breathing critically ill patients. J Crit Care. 2017;41:130–7.View ArticlePubMedGoogle Scholar
    4. Talbert A, Thuo N, Karisa J, Chesaro C, Ohuma E, Ignas J, Berkley JA, Toromo C, Atkinson S, Maitland K. Diarrhoea complicating severe acute malnutrition in Kenyan children: a prospective descriptive study of risk factors and outcome. PLoS One. 2012;7(6):e38321.View ArticlePubMedPubMed CentralGoogle Scholar


    © The Author(s). 2017