Changes of Spinal Evoked Potentials in Acute Decompress ion Sickness of Rats

Changes of spinal evoked potentials (SEP) were observed in rats by stimulatingthe sciatic nerves on both sides under various pressure conditions (normal,hyperbaric,rapid decompression,safe decompression,and recompression treatment) and in acuteanoxia.It was observed that occurence of acute decompression sickhess (DCS) was relatedwith changes of SEP.The changes of SEP late components (N_3,P_3,N_2) occurred earlierthan SEP early components (P_2,N_1,P_4).It was shown that in using SEP method tomonitor DCS,late components were more sensitive as compared with early components andspecial attention should be given to the amplitudes of SEP.As soon as changes of latecomponents appeared,acute DCS would follow.If recompression would be given at thispoint,DCS could be reduced or eliminated.When early components showed changes,DCSwas in such a stage as to cause immediate death of the animals.Recompression had noeffects at this point.The late components and early components,therefore,were ofsignificantly different value in reflecting the level of DCS.N_2 wave was an important key.The results suggest that using the SEP method to monitor acute DCS is a sensitive andaccurate way.

Changes of Spinal Evoked Potentials in Acute Decompress ion Sickness of Rats

Changes of spinal evoked potentials (SEP) were observed in rats by stimulating the sciatic nerves on both sides under various pressure conditions (normal,hyperbaric, rapid decompression,safe decompression,and recompression treatment) and in acute anoxia.It was observed that occurence of acute decompression sickhess (DCS) was related with changes of SEP.The changes of SEP late components (N_3,P_3,N_2) occurred earlier than SEP early components (P_2,N_1,P_4).It was shown that in using SEP method to monitor DCS,late components were more sensitive as compared with early components and special attention should be given to the amplitudes of SEP.As soon as changes of late components appeared,acute DCS would follow.If recompression would be given at this point,DCS could be reduced or eliminated.When early components showed changes,DCS was in such a stage as to cause immediate death of the animals.Recompression had no effects at this point.The late components and early components,therefore,were of significantly different value in reflecting the level of DCS.N_2 wave was an important key. The results suggest that using the SEP method to monitor acute DCS is a sensitive and accurate way.