Prospective randomized double‐blind trial of branched chain amino acid enriched versus standard parenteral nutrition solutions in traumatized and septic patients

Abstract

The addition of branched chain amino acids (BCAA) to total parenteral nutrition (TPN) solutions of balanced aminoacid composition has been reported to result in improved nitrogen balance, preservation of plasma protein levels, and improved immune function; however, only a few large clinical studies have been performed, yielding conflicting results. We, therefore, studied in a prospective, randomized double blind trial, the effects of BCAA enrichment of an otherwise isonitrogenous and isocaloric TPN solution on plasma protein levels in 101 traumatized and septic patients. TPN-derived nitrogen intake was similar in both study groups. Nitrogen balances in the BCAA group (n = 49) were not different from those in the standard group (n = 52). Plasma total protein levels increased significantly in the standard group resulting in a significant difference between study groups on day 7. Pre-albumin levels increased significantly in the BCAA group and in the standard group. The number of neutrophils (rods) was significantly lower in the standard group compared to the BCAA group on day 7. Lymphocytes increased significantly in the standard group as did the number of platelets, resulting in a significant difference between study groups on day 7. We conclude that BCAA enrichment of standard TPN solutions does not result in more efficient nitrogen metabolism in septic or traumatized patients.

Extracellular Branched-Chain Amino Acids, Especially Valine, Regulate Maturation and Function of Monocyte-Derived Dendritic Cells

“…In clinical situations, the administration of BCAA was reported to increase the number of peripheral lymphocytes and improve opportunistic infections or immune functions (9,10). In advanced cirrhosis, long-term nutritional supplementation with oral BCAA has been shown to be useful to prevent progressive hepatic failure and to improve surrogate markers and the perceived health status (7).…”

“…BCAA granules (a mixture of L-leucine, L-valine, and L-isoleucine) have been used to effectively reverse the hypoalbuminemia and hepatic encephalopathy in patients with decompensated liver cirrhosis (6, 7), but little is known about the impact of changes in the BCAA levels on the immune system (8). In previous cohort studies, the BCAA-supplemented groups demonstrated elevations in the absolute lymphocyte count (9,10). In previous in vitro studies, the omission of a single BCAA from the medium of cultured lymphocytes resulted in the complete abolition of protein synthesis or proliferation (11)(12)(13).…”

Beneficial effects of supplementation with branched-chain amino acids on postoperative bacteremia in living donor liver transplant recipients

“…Previous studies have shown the impact of changes in BCAA levels on the immune system. In previous cohort studies,27, 28 the BCAA supplementation groups showed elevated absolute lymphocyte counts. Bassit et al29 reported that BCAA supplementation restored the ability of peripheral blood mononuclear cells to proliferate in response to mitogens after long‐distance intensive exercise.…”

Pharmaconutrition Review

“…In burn patients, BCAA supplementation sustained mild inhibition of protein catabolism in some studies, as assessed by reduced urinary 3‐methylhistidine/creatine ratios, but these studies were confounded by small sample size and the use of all 3 BCAAs 89 , 90 . Likewise, some larger studies in trauma, ICU, and septic patients have shown improvements in nitrogen balance or the half‐life of visceral proteins but few improvements in mortality 91 – 94 . Furthermore, the vast majority of these studies used valine and isoleucine, in addition to leucine, and we now know that these other BCAAs do not stimulate protein synthesis and instead compete with leucine for transport into muscle cells and use shared metabolic pathways 95 .…”