RT Journal Article
SR Electronic
T1 Varying association of laboratory values with reference ranges and outcomes in critically ill patients: an analysis of data from five databases in four countries across Asia, Europe and North America
JF BMJ Health & Care Informatics
JO BMJ Health Care Inform
FD BMJ Publishing Group Ltd
SP e100419
DO 10.1136/bmjhci-2021-100419
VO 28
IS 1
A1 Haoran Xu
A1 Louis Agha-Mir-Salim
A1 Zachary O’Brien
A1 Dora C Huang
A1 Peiyao Li
A1 Josep Gómez
A1 Xiaoli Liu
A1 Tongbo Liu
A1 Wesley Yeung
A1 Patrick Thoral
A1 Paul Elbers
A1 Zhengbo Zhang
A1 María Bodí Saera
A1 Leo Anthony Celi
YR 2021
UL http://informatics.bmj.com/content/28/1/e100419.abstract
AB Background Despite wide usage across all areas of medicine, it is uncertain how useful standard reference ranges of laboratory values are for critically ill patients.Objectives The aim of this study is to assess the distributions of standard laboratory measurements in more than 330 selected intensive care units (ICUs) across the USA, Amsterdam, Beijing and Tarragona; compare differences and similarities across different geographical locations and evaluate how they may be associated with differences in length of stay (LOS) and mortality in the ICU.Methods A multi-centre, retrospective, cross-sectional study of data from five databases for adult patients first admitted to an ICU between 2001 and 2019 was conducted. The included databases contained patient-level data regarding demographics, interventions, clinical outcomes and laboratory results. Kernel density estimation functions were applied to the distributions of laboratory tests, and the overlapping coefficient and Cohen standardised mean difference were used to quantify differences in these distributions.Results The 259 382 patients studied across five databases in four countries showed a high degree of heterogeneity with regard to demographics, case mix, interventions and outcomes. A high level of divergence in the studied laboratory results (creatinine, haemoglobin, lactate, sodium) from the locally used reference ranges was observed, even when stratified by outcome.Conclusion Standardised reference ranges have limited relevance to ICU patients across a range of geographies. The development of context-specific reference ranges, especially as it relates to clinical outcomes like LOS and mortality, may be more useful to clinicians.Data are available in a public, open access repository. Data are available upon reasonable request. MIMIC, eICU-CRD, and AUMCdb are freely accessible. Data from PLAGH-ICUdb and UCIHJ23db are available upon request.