Investigation of bone developmental and histopathologic changes from intraosseous infusion.

STUDY OBJECTIVE: To evaluate clinical and cellular changes of bone through the rapid growth phase of development after intraosseous infusion of hypertonic or isotonic solutions at slow or fast infusion rates in a pig model.

METHODS: This was a prospective, randomized, partially blinded, comparative study using a porcine model in an urban teaching hospital laboratory with further development in a local farm environment. Sixty pigs weighing 12 to 30 kg were anesthetized and endotracheally intubated, and a no. 15 Jamshidi bone marrow needle was inserted into a front forelimb. Hypertonic (mannitol) or isotonic (saline) solutions of 8 mL/kg were infused through the intraosseous site at a rapid or slow infusion rate. Animals were observed for approximately 6 months, after which they were killed and the front forelimbs harvested for gross pathologic and histologic evaluation.

RESULTS: No clinical complications were noted in any of the animal groups. No substantial histologic differences were found between the hypertonic and isotonic groups. Although gross pathologic lesions were found in 32% of the hypertonic groups and in fewer than 5% of the isotonic groups, this difference was not statistically significant. Equal bone changes were found in the slow- and rapid-infusion groups.

CONCLUSION: The rate of intraosseous infusion and the osmolarity of the infused fluid did not appear to be related to any gross pathologic or histologic cellular or marrow changes or to any clinical complications in animal development in this study.