State of a kernel when it's running?

Exist any way to know the state of a kernel when it’s running??

I’m not sure about the meaning of your question, but if you get the event returned by clEnqueueNDRangeKernel, you can get the status of the command with clGetEventInfo with CL_EVENT_COMMAND_EXECUTION_STATUS.
Note however that you get the status of the command, not the status of the kernel, which is slightly different (the command can still be running while the kernel has not yet started or has already finished).