Metabolomic Fingerprinting Offers Insight on ICU Length of Stay and Mortality

Research study background 

A study published in 2018 evaluated metabolic changes in infants 120 days old or younger undergoing cardiopulmonary bypass. The prospective cohort study sought to identify individual metabolites that could potentially be biomarkers for post-operative mortality and intensive care unit (ICU) length of stay. 

Study authors, including Children’s Hospital Colorado researchers Jesse Davidson, MD, MPH, and Benjamin Frank, MD, used tandem mass spectrometry to measure 165 serum metabolites across multiple metabolic pathways.

Sample collection included 82 infants with preoperative samples, and 57 also had rewarming and 24-hour samples.

Sample analysis  

• Review changes in metabolome  
• Assess altered metabolic pathways  
• Differentiate between survivors, non-survivors; longer, shorter ICU length of stay  

Findings 

• Pre-operative metabolic fingerprint of neonates significantly different than in older infants  
• Cardiopulmonary bypass led to substantial changes in both younger and older infants’ metabolic fingerprints
  • 84% of metabolites dysregulated postoperatively 
  • Spanned more than 24 hours
  • Included age-dependent, ongoing depletion of amino acid levels 
  • Biomarkers most impacted after surgery: arginine/proline, glutathione, alanine/aspartate/glutamate, nicotinamide metabolism
• Imbalances in aspartate, nicotinamide, and tryptophan metabolism distinguished between survivors and non-survivors and identified patients with prolonged ICU length of stay

Conclusions

While additional research is needed, preliminary evidence found an association between changes in specific metabolites and outcomes, which may help identify high-risk patients.