Musnad Ahmad 33:1027

Hassan narrated to us, Zuhair narrated to us, from Abu al-Zubayr, from Jabir, who said: Sa’d ibn Mu’adh was struck in his median arm vein (akhal), and the Messenger of Allah (may Allah bless him and grant him peace) cauterized him with his own hand using a broad-headed arrow. He said: Then it swelled. He said: So he cauterized him a second time.