Volume 19 Supplement 2

Eighth International Symposium on Intensive Care and Emergency Medicine for Latin America

Open Access

Prognostic value of the hemolysis index in patients with significant hemolysis

  • Diego O Cortés1,
  • Arthur Cezar M Xavier1,
  • Bruno R Almeida1,
  • Érica C Vieira1,
  • Jacques Creteur1,
  • Jean-Louis Vincent1,
  • Joao Claudio Lyra1 and
  • Sylmara Zandona1
Critical Care201519(Suppl 2):P10


Published: 28 September 2015


Hemolysis is a frequent complication of different extracorporeal circulation and membrane oxygenation (ECMO) support systems. Usually it is assessed by measuring the levels of haptoglobin or the concentrations of free hemoglobin in the plasma, but automated biochemical laboratory analyzers now detect the hemolysis index (HI) of all blood samples as a measure of sample quality. We studied whether this simple index could detect populations at high risk of active hemolysis and whether it is correlated with outcome.


We evaluated all admissions to our department of intensive care during 2013 and collected relevant demographic and organ dysfunction data during the first 24 hours as required for the SOFA score (not the neurological component). We also collected data on whether or not the patients needed renal replacement therapy during the ICU stay. Patients were classified into three groups: those who needed ECMO support during the ICU stay, those who were admitted after cardiac surgery and had cardiopulmonary bypass (CPB), and other patients. We compared the initial and median (throughout the ICU stay) HI values in the different groups and the survivors with the nonsurvivors. We used SPSS 22.0 (IBM, USA) for all analyses and a p value < 0.05 was considered as significant.


We studied 2021 patients with the characteristics presented in Table 1. Patients treated with ECMO and cardiac surgery patients had higher initial and median HI values than the other patients. The nonsurvivors in the ECMO group had higher median HI values than survivors (4 (2-21) vs. 2 (1-3), p < 0.01). There were no differences in the initial or median HI values between patients treated or not with renal replacement therapy.
Table 1

Characteristics and hemolysis index in different groups.


ECMO (n= 56)

CBP (n= 246)

Others (n= 1719)


Age (years)

53 (38-61)

68 (59-78)

59 (45-70)


Emergency surgery, n (%)

4 (7)

10 (4)

177 (10)


Lowest mean arterial pressure in first 24 hours (mmHg)

64 (60-69)

65 (61-69)

71 (64-82)


Norepinephrine use in first 24 hours, n (%)

49 (88)

143 (58)

363 (21)


Renal replacement therapy during ICU stay, n (%)

22 (39)

13 (5)

109 (6)


Transfusion during first 48 hours, n (%)

41 (73)

76 (31)

223 (13)


Renal failure at admission, n (%)

35 (63)

51 (21)

440 (26)


SOFA score at admission

9 (7-11)

6 (4-7)

3 (1-5)


Mortality, n (%)

26 (46)

15 (6)

186 (11)


Initial hemolysis index

7 (2-18)

11 (4-21)

2 (0-4)


Median hemolysis index

2 (1-4)

3 (1-5)

2 (0-3)



Patients undergoing CBP for cardiac surgery and those treated with ECMO support had higher HI values measured automatically in contemporary analyzers. The HI had prognostic value in patients treated with ECMO.

Authors’ Affiliations

Department of Intensive Care, Hôpital Erasme


© Cortés et al. 2015

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 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.