Background: Preoperative poor nutrition greatly raises the risk of complications and increases
length of stay (LOS). Glutamine deficiency may impair immune functions, reduce myocardial
adenosine triphosphate–adenosine diphosphate (ATP-ADP) substrate and decrease myocardial
glutathione level. We evaluated the effects of preoperative glutamine administration in
patients undergoing mitral valve replacement surgery upon cardiac and renal outcomes or
hospital/ICU LOS.
Methods: This prospective randomized double-blinded study included 60 patients above 18
up to 60 years undergoing mitral valve replacement. For 3 days preoperatively, Group
N patients received glutamine intravenously 0.4 g/kg/day while Group C patients received
intravenous normal saline as placebo. The primary outcome was to assess the effects of
glutamine on cardiac function as reflected on proBNP (brain natriuretic peptide) during 4
postoperative days. Secondary outcomes included renal function, vasoactive inotropic score,
duration of mechanical ventilation, and hospital/ICU stays.
Results: Postoperative proBNP was significantly lower in Group N during the entire period. It
was significantly decreased on the first postoperative day in both groups in comparison to the
preoperative values. No significant changes were recorded regarding renal functions, and
duration of mechanical ventilation between groups. Also, there was signifiacant difference
between the two studied groups regarding the vasoactive inotropic score at the 12th, 18th,
24th and 48th hours with lower scores in Group N. ICU and hospital stays were significantly
lower in Group N than Group C.
Conclusion: Short term of preoperative intravenous glutamine 0.4 g/kg/day decreased the
postoperative proBNP level and hospital/ICU stays in mitral valve replacement surgery. No
significant implication was reported upon postoperative human NGAL level or kidney
functions.