Laser scalpel

The laser scalpel was a medical instrument employed by the humanoid surgeon Crozier, on Thoros Beta, during a brain transplant. (TV: Mindwarp) They cauterised as they cut. (AUDIO: The Burning Prince) The Seventh Doctor had one in his TARDIS; Hex once stole it for use in helping cure the sick of the Scutari barracks. He tried to get Florence Nightingale to use it on him after he was shot in the chest, but if was destroyed before she could use it (AUDIO: The Angel of Scutari). Princess Aliona of the Drashani Empire's Royal House of Gadarel used one to sever the hand of Prince Kylo of the rival House of Sorsha. (AUDIO: The Burning Prince)

According to the Sixth Doctor, a healing beam worked better than "the old laser scalpel". (TV: The Twin Dilemma)