Figure 1-16 One of Harvey Cushing's early anesthesia records shows systolic blood pressure (top tracing) and pulse rate (bottom tracing). The first rise in blood pressure occurred during the excitement phase of ether induction, and the second rise occurred during the release of adhesions of the sciatic nerve. Vertical lines take place 2.5 minutes apart. The systolic blood pressure rose to greater than 230 mm Hg during the operation. Cushing was an early proponent of regional anesthesia, possibly stemming from his observations on blood pressure and heart rate.^[382] (From Cushing H: On routine determination of arterial tension in operating room and clinic. Boston Med Surg J 148:250–256, 1903.)