Km. Silvers et al., Lipid peroxide and hydrogen peroxide formation in parenteral nutrition solutions containing multivitamins, J PARENT EN, 25(1), 2001, pp. 14-17
Background: Infusion of parenteral solutions containing peroxides may be de
trimental to premature infants. Intralipid frequently contains lipid peroxi
des and undergoes further peroxidation when exposed to light. Peroxidation
is inhibited by ascorbate, and we have proposed that administration of pero
xides could be minimized by mixing multivitamins with the Intralipid. In co
ntrast, others have reported that multivitamins generate peroxides and have
advised against mixing them with lipid. Our objective was to assess whethe
r light-dependent reactions in parenteral solutions containing MVI Pediatri
c (MVIP) generate hydrogen peroxide and establish whether addition of multi
vitamins to Intralipid is beneficial or detrimental. Results: We were unabl
e to make accurate peroxide measurements in MVIP using the ferrous oxidatio
n of xylenol orange (FOX) assay, even though others have used it for this p
urpose, because of interference by ascorbate. Therefore oxygen release on a
dding catalase was measured to assay for hydrogen peroxide. Freshly reconst
ituted solutions contained 250 to 500 mu mol/L hydrogen peroxide, and this
increased dramatically in ambient light. This is presumably due to light-de
pendent, riboflavin-catalyzed reduction of oxygen by ascorbic acid. The rat
e of peroxide generation was less for MVIP diluted in Intralipid than in de
xtrose solution. Conclusions: Taken together with our previous findings, we
conclude that multivitamins protect Intralipid against lipid peroxidation,
but light-dependent hydrogen peroxide production and ascorbate loss occur.
These latter changes are less than for multivitamins in other total parent
eral nutrition solutions, so there is an advantage in mixing multivitamins
with Intralipid. However, prevention of ascorbate loss and hydrogen peroxid
e formation in any multivitamin solution requires protection of the deliver
y system from light.