ABSTRACT
Malnutrition, particularly amino acid deficiency, decreases the ventilatory response to hypoxemia43. The immune system responds to malnutrition with decreased cell-mediated immunity, altered IgG turnover, and impaired macrophage function44. In 47 patients who received mechanical ventilation for 3 days or more, 93% of those with adequate nutritional support could be weaned; however, only half of those with inadequate nutritional support could be weaned45. Among 14 'unweanable' medical patients, all those who responded with increases in albumin and transferrin during parenteral nutrition were eventually weaned, but those who showed no biochemical response to nutrition remained unweanable46. Amino acids are an essential part of parenteral nutrition, and have been shown to restore ventilatory drive and improve both minute ventilation and respiratory rate43.
