As "Baltimore" told me, Sacraments are "outward signs that give grace".  The emphasis is, I believe, on the "outward sign" and that the "giving grace" is the work of God and not limited to any "outward sign". 
If water or even a can of coke or, even, a hand to pour and tongue to say the words, a child dying alone is as "baptized" in Christ as is the frilly-white-gowned baby with "holy water", candle, exorcism and oil.