Plasma Amino Acid Profiles and Clinical Outcome in Patients with Traumatic Brain Injury: A Study Protocol

Plasma Amino Acids and TBI Patients


  • Alireza Gheflati Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
  • Mostafa Shahraki Jazinaki Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
  • Mahlagha Nikbaf-Shandiz Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
  • Pegah Rahbarinejad Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
  • Hamid Rezaee Department of Neurosurgery, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
  • Saeid Eslami 1-Department of Medical Informatics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran/ 2-Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
  • Majid Khadem-Rezaian Department of Community Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
  • Alireza Sedaghat Department of Anesthesiology, Mashhad University of Medical Sciences, Mashhad, Iran
  • Mohsen Nematy 1-Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran/ 2-Metabolic Syndrome Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
  • Mahdi Shadnoush Department of Clinical Nutrition, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Ali Jafarzadeh Esfehani Metabolic Syndrome Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
  • Fatemeh Keyfi 1-Department of Medical Laboratory Sciences, Varastegan Institute for Medical Sciences, Mashhad, Iran/ 2-Division of Metabolic Disorder, Pardis Clinical and Genetic Laboratory, Mashhad, Iran
  • Zachary S. Clayton Department of Integrative Physiology, University of Colorado, Boulder, CO, USA
  • Abdolreza Norouzy 1-Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran/ 2-Metabolic Syndrome Research Center, Mashhad University of Medical Sciences, Mashhad, Iran


Traumatic Brain Injury, Mortality, Amino Acid, Clinical Protocols


The most common cause of cognitive and behavioral impairments, disability, and mortality around the world is traumatic brain injury (TBI). The imbalance between cerebral metabolism and inflammation leads to protein breakdown and induces altered concentrations of serum amino acids, which can serve as a diagnostic and prognostic sign in patients with TBI. This study aimed to examine the alterations in plasma amino acid concentrations and their relation to clinical outcomes in patients with TBIs.
Materials and Methods: At completion, this study will assess 107 patients suffering from TBI aged 18 to 65. Plasma amino acid concentrations, anthropometric indices, and clinical outcome parameters including Acute Physiology and Chronic Health Evaluation (APACHE) II, Sequential Organ Failure Assessment (SOFA), Nutrition Risk in the Critically ill (Nutric) score, Glasgow coma scale (GCS), Intensive Care Unit (ICU) discharge time, mechanical ventilator duration, and mortality rate will be assessed at the beginning of the study, day 7, and day 14.
Conclusion: This longitudinal study will provide evidence for further clinical trials and observational studies on amino acid supplementation and TBI. The results of this study could inform future treatment strategies for TBI patients.


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Study Protocol