An Inflatable Emergency Splint
A modification of the aviation antigravity garment (G-suit) was employed as a last resort in a case of nearly fatal uterine hemorrhage and proved dramatically effective.1 This demonstration in 1955 suggested that the same pneumatic principle should be equally effective in controlling bleeding from a traumatized limb. Experimental models consisting of a double-walled inflatable sleeve of uncleared, 8-mil vinyl film were made which would completely encompass an arm or a leg. Applied to the human subject, these sleeves unexpectedly were found to splint the limbs, and also, because of a tendency to elongate during inflation, to exert spontaneous traction in its long axis (Fig. 1). It was further discovered that no amount of additional traction would dislodge the sleeve from the limb.
Small models for the experimental animal then were made of transparent vinyl. They were open at both ends so that manual traction on the limb could be maintained during the application of the splint. Applied to the lacerated leg of an anesthetized dog and inflated to 20 mm. of Hg, i.e., below capillary pressure, these sleeves were observed to arrest completely venous bleeding. When the femoral artery was divided, bleeding from it did not completely cease until the pressure in the sleeve was higher than the animal’s systolic pressure. However, with the transparent sleeve inflated to diastolic pressure, only a tiny spurt of blood was seen to occur at the systolic peak. During the remainder of the pulse cycle, the cut end of the artery was entirely collapsed.