PubMed1978
Lesions (thrombosis, intimal damage, perivascular inflammation) of the marginal ear vein of domestic rabbits were studied 48 hours after infusions of parenteral feeding solutions administered through a butterfly-type 25 needles. Six-hour infusions with a rather diluted solution (12 g dextrose, 1.25 g. aminoacids, 1.5 mEq., Na, Cl, K and PO4 and 1.5 mEq. Ca and Mg per 100 ml.) with osmolality of 930 and pH of 6.9 were slightly harmful, while the lesions were considerable after 12-hours infusions. A more concentrated solution (15.83 g. dextrose, 2.08 g. aminoacids, 2.5 mEq. Na, Cl, K and PO4 0.2 MEq. Ca and Mg per 100 ml.) with osmolality of 1,600 and pH 6.7 produced severe lesions both after 6 and 12-hours infusions. Similar results were obtained with a mixture of this solution with intralipid at clinical doses (4 g. fat for 100 ml. of solution). This mixture had 1,280 mOsm/1. and pH of 6.7. Rather surprisingly the lesions were even more marked when intralipid alone was infused (osmolality 317, pH 7.5). These results lead to the conclusion that practically all fluids used for parenteral feeding purposes either centrally or peripherally, are considerably harmful for the venous wall after a few hours of infusion, probably due to their shifts from isoosmolality and chemical neutrality. Specially puzzling was the harmful local effect of the otherwise well tolerated intralipid.