A model of spinal cord dysbarism to study delayed treatment: II. Effects of treatment.

Using the spinal cord decompression sickness model described in Part I, we explored the effects of delay to treatment on the recovery of spinal evoked potentials (SEP). The primary treatments of oxygen at 60 fsw (2.8 bar) and air at 165 fsw (6.0 bar) were studied. In this exploratory study the results were surprisingly poor in all treatments applied. There is evidence that in this model a delay of 15-18 min between diagnosis and start of therapy would generally allow some recovery of SEP, which would rarely be complete. Supporting experiments involving cord ischemia are described. The results from this study enabled us to design a set of practicable experimental criteria for the purpose of discovering the optimal combinations of oxygen and pressure for the treatment of spinal cord decompression sickness.