Then war broke out in heaven; Michael and his angels battled against the dragon. The dragon and its angels fought back, but they did not prevail and there was no longer any place for them in heaven. Revelation 12: 7-8
I just found out that St. Michael the Archangel is the patron saint of paramedics! Who better than this heavenly warrior to guard those who are looking after the lives of others? I wonder if St Michael was named patron of paramedics in 1884 when Pope Leo XII had his vision of the battle between Satan and Jesus. The Pope had finished saying Holy Mass, and he collapsed. Those around him could not find a pulse and thought the Pope had died, but he was actually in ecstasy.
From in front of the Tabernacle, Pope Leo XII had heard a confrontation between Jesus and Satan. Satan was bragging to Jesus that if he had enough time and enough power, he could destroy the Church. Jesus asked him "How much time and how much power?" Satan replied he would need a century and more influence over those that would give themselves to him. Jesus said "So be it."
The Pope immediately composed the Laentein Exorcism Prayer, of which the well known Prayer to St. Michael the Archangel is the short version. He also composed thirteen encyclicals on the Holy Rosary, knowing that this is the greatest weapon there is to defeat Satan.
St. Michael the Archangel, defend us in the day of Battle; Be our safeguard against the wickedness and snares of the Devil. May God rebuke Him, we humbly pray, and do Thou, O Prince of the Heavenly Host, by the power of God, cast into Hell, Satan and all the other evil spirits, who prowl through the world, seeking the ruin of souls. Amen.
1)To fight against Satan and his host of fallen angels
2)To rescue the souls of the faithful from the power of the enemy, especially at the hour of death
3)To be the champion of God's people, the Jews in the Old Law, the Christians in the New Testament; therefore he was the patron of the Church, and of the orders of knights during the Middle Ages.
4)To call away to heaven those who have died, and bring their souls to Judgment
Looking at the above list, maybe it's number two that is the reason St. Michael is the patron of paramedics.