Surgical, medical, dental and veterinary instruments, namely, powered intraosseous access system, namely, comprising a needle used to access bone marrow spaces during diagnostic surgical procedures, and namely, a reservoir to automatically inject or aspirate fluid from the intraosseous space, namely, bone marrow biopsy needles for obtaining samples for bone marrow transplants, namely, diagnostic instruments in the nature of intraosseous needles to sample marrow for medical diagnostics and cancer, and namely, pressure sampling instruments in the nature of pressure probes to measure intracranial pressure in cases of head trauma and other intracranial pathology