Introduction
Critically ill patients have considerable inflammatory response which
affects metabolism and metabolic changes may occur due to different
etiologies including stroke, sepsis, multiple trauma, burns, and
respiratory failure. Metabolic changes are associated with systemic
inflammatory response that leads to increased multi-organ failure,
sepsis, immunosuppression, duration of mechanical ventilation, length of
hospital stay, and higher mortality rate (1-3). Various reasons are
considered for malnutrition during hospitalization including severe
inflammation, increased metabolic requirements, oxidative stress,
delayed or stop in enteral and parenteral nutrition for medical
intervention treatment that may worsen catabolic status (4, 5).
L-Carnitine (B-hydroxy- γ- trimethyl l- aminobutyric acid, LC) is an
essential compound that is synthesized from lysine and methionine in the
liver and kidney or its mainly supplied from animal diet sources such as
meat and dairy product (6). L-Carnitine is necessary for beta-oxidation
of long-chain fatty acids and fatty acid transport via Carnitine
palmitoyltransferase I (CPT1) into the inner membrane of mitochondria.
Therefore, L-Carnitine plays a critical role in energy metabolism (7).
L-Carnitine deficiency may result in mitochondrial dysfunction and
failure in lipid utilization by vital organs (8, 9). L-Carnitine
deficiency leads to beta-oxidation disorder due to depletion in fatty
acyl coenzyme A (CoA), which is required for lipid oxidation, and
depletion of CoA enzyme pool. Therefore, mitochondrial dysfunction will
occur and result in metabolic changes and multi-organ dysfunction. Oamiet al. showed that carnitine deficiency occurs in 23.4 % of
critically ill patients (10). It has been shown that L-Carnitine
supplementation at a dose of 1-3 gr decreases the effect of inflammation
in non-communicable disease (11-13). Therefore, L-Carnitine may have the
potential effect in inflammatory disease by reducing inflammatory
markers, including C - reactive protein (CRP) and interlukin-6 (IL-6).
To the best of our knowledge, the anti-inflammatory effect of
L-Carnitine supplementation in critically ill patients was poorly
investigated. In addition, there is no published study, which assessed
the effects of L-Carnitine supplementation for seven days on
inflammatory and clinical outcomes of the intensive care unit (ICU)
patients who fed only with enteral nutrition Therefore, the purpose of
this study was to evaluate the effects of L-Carnitine supplementation
(with dose 3000 mg/day) on clinical status, inflammatory markers, and
28-days mortality in critically ill patients who admitted to the ICU.