Minimally invasive assessment of hepatic function in children with indocyanine green elimination: a validation study

Abstract

Objectives: Pediatric liver disease (PLD) covers a variety of etiologies and severities, from mild temporary illness to diseases with fatal outcomes. There is a demand for minimally invasive and reliable measures for assessment of the severity of PLD. Indocyanine green (ICG) elimination kinetics to estimate hepatic function has been used in adults for decades, however, due to invasiveness, the use in PLD is still limited. The aim of the present study was to evaluate minimally invasive estimation of ICG elimination by pulse spectrophotometry (ICGLi), in comparison with traditional spectrophotometry using serial blood samples (ICGbs).

Methods: One hundred children aged 0–18 years were included in the study. ICG elimination kinetics was measured with ICGLi and ICGbs, and results compared by failure rates, mean difference, limits of agreement, Bland Altman plots and linear regression analysis. Plasma disappearance rates (PDRLi and PDRbs) were used for comparison.

Results: One hundred and twelve simultaneous measurements in 87 patients were performed successfully. Mean difference for PDR (%/min) was 3.58 (95% CI 2.69; 4.47). Limits of agreement were −5.06; 12.22. A linear correlation between the two methods with a regression coefficient of 0.83 (SE 0.02 95% CI 0.80; 0.87) was found. For conversion we computed the following equation; PDRbs = 0.83 × PDRLi.

Conclusions: The present study shows that ICG PDR can be obtained by a minimally invasive method and thus replace measures by serial blood samples in children with liver disease of different etiologies and severities. However, a systematic relative difference between the two methods exists. Our proposed correction factor needs to be validated in larger cohorts.

Trial registration: ClinicalTrials.gov identifier: NCT03509194.

Keywords:

• Pediatric liver disease
• biliary atresia
• autoimmune hepatitis
• liver transplantation
• indocyanine green
• liver function tests

Acknowledgements

The authors sincerely thank the technologists at Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet responsible for performing the examinations; Anna Viktoria Setterberg, Mariam Hassan, Britt Maria Tolstrup, and Birgit Krindel Beyer for logistics. Also, sincere thanks to the technologists Annemarie Engelbreth Hersland, Katrine Marie Lyngby, Bente Pedersen, Pernille Lemvig and physicist Stefan Fuglsang, Department of Clinical Physiology, Hvidovre Hospital for their work with blood analyses. We are very grateful for the Department of Anesthesiology, Copenhagen University Hospital, Rigshospitalet to provide the LiMON device available for this study.

Disclosure statement

No potential conflicts of interest was reported by the authors.

Additional information

Funding

The study was partly funded by The Research Fund of Copenhagen University Hospital Rigshospitalet