Effect of 3-hydroxybutyrate on posttraumatic metabolism in man.
Level 3 - non-randomized controlled study
Controlled clinical trial without explicit statement of randomization
What was done
In 20 patients with severe trauma (Injury Severity Score > 20), 11 received an intravenous infusion of DL-3-hydroxybutyrate (3-OHB) at 25 µmol/kg/min for 3 hours, while 9 control patients received sodium DL-lactate at the same rate. Arterial and femoral venous substrate concentrations were measured to assess extremity arteriovenous exchange of ketone bodies, free fatty acids, and amino acids.
What was found
Arterial ketone body increases correlated with increased femoral arteriovenous uptake in the 3-OHB group (R = 0.853, p < 0.001). Compared to controls, venous concentrations and femoral venous-minus-arterial concentration differences of nonesterified free fatty acids, alanine, glycine, and valine decreased significantly with 3-OHB. Specifically, venous alanine concentration fell by 102.3 ± 69.3 µmol/L and the femoral venous-arterial difference decreased by 32.6 ± 22.8 µmol/L (mean ± SD), reflecting suppressed extremity alanine release.
Why it matters
Acute infusion of ketone bodies directly suppresses skeletal muscle amino acid efflux, providing physiological evidence that ketosis may mitigate post-traumatic protein catabolism.
Limits
The study evaluated a very small cohort (n = 20) over a short 3-hour intervention. Randomization and blinding methods are not described in the abstract. Whole-body protein turnover, nitrogen balance, and clinical outcomes were not measured.
Cited by
- supports Elevating circulating ketone levels reduces the liberation of alanine from skeletal muscle during stress and gluconeogenic states.