What Causes The Body To Be Under The Influence Of Anesthesia For 8 Hours?

i had my tubes tied which was suppose to be approximately 45 minutes surgery. however, afterward i was in a coma state for 8 hours because my body couldn't fight off the anesthia. i could hear everything and feel all the painful things they were doing to me but my body would not respond. is this because i have thalasemia minor