An ultrasonic surgical instrument, comprising: (a) an end effector configured to actuate from a first configuration to a second configuration, including: (i) an ultrasonic blade configured to selectively to apply ultrasonic energy to a tissue, and (ii) an RF electrode configured to selectively to apply RF energy to the tissue, wherein the RF electrode is further configured to measure a tissue impedance of the tissue engaged by the end effector; (b) a shaft assembly projecting proximally from the end effector; (c) a body proj ecting proximally from the shaft assembly, wherein the body includes an energy input (36, 68, 40) operatively connected to the ultrasonic blade; and (d) a power controller operatively connected to the ultrasonic blade, the RF electrode, and the energy input, wherein the power controller is configured to selectively direct activation of at least one of the ultrasonic blade or the RF electrode, wherein the power controller is further configured to interrogate the tissue with an electrical signal via at least one of the ultrasonic blade or the RF electrode to provide a tissue feedback, wherein the power controller is further configured to determine a relative size of the interrogated tissue based on the tissue feedback, and wherein the power controller is further configured to adjust an electrical parameter (632, 634, 636) of at least one of the ultrasonic energy or the RF energy in response to the determined relative size of the interrogated tissue based on the tissue feedback to inhibit transecting the tissue. (a) an end effector configured to actuate from a first configuration to a second configuration, including: (i) an ultrasonic blade configured to selectively to apply ultrasonic energy to a tissue, and (ii) an RF electrode configured to selectively to apply RF energy to the tissue, wherein the RF electrode is further configured to measure a tissue impedance of the tissue engaged by the end effector; (i) an ultrasonic blade configured to selectively to apply ultrasonic energy to a tissue, and (ii) an RF electrode configured to selectively to apply RF energy to the tissue, wherein the RF electrode is further configured to measure a tissue impedance of the tissue engaged by the end effector; (b) a shaft assembly projecting proximally from the end effector; (c) a body proj ecting proximally from the shaft assembly, wherein the body includes an energy input (36, 68, 40) operatively connected to the ultrasonic blade; and (d) a power controller operatively connected to the ultrasonic blade, the RF electrode, and the energy input, wherein the power controller is configured to selectively direct activation of at least one of the ultrasonic blade or the RF electrode, wherein the power controller is further configured to interrogate the tissue with an electrical signal via at least one of the ultrasonic blade or the RF electrode to provide a tissue feedback, wherein the power controller is further configured to determine a relative size of the interrogated tissue based on the tissue feedback, and wherein the power controller is further configured to adjust an electrical parameter (632, 634, 636) of at least one of the ultrasonic energy or the RF energy in response to the determined relative size of the interrogated tissue based on the tissue feedback to inhibit transecting the tissue. wherein the power controller is further configured to interrogate the tissue with an electrical signal via at least one of the ultrasonic blade or the RF electrode to provide a tissue feedback, wherein the power controller is further configured to determine a relative size of the interrogated tissue based on the tissue feedback, and wherein the power controller is further configured to adjust an electrical parameter (632, 634, 636) of at least one of the ultrasonic energy or the RF energy in response to the determined relative size of the interrogated tissue based on the tissue feedback to inhibit transecting the tissue.