i definately say take the 4 weeks if you can. i wouldnt risk it. especially since as a tech we are the ones that get killed the most. i know i do, especially working in an ER when we have a new patient rolling thru the door every few minutes that have to be moved onto cart or onto an xray or ct table. Just listen to your body, you will know when its too much. the first week back i made myself useful in other ways by having the room ready with equipment, monitoring, vitals and blood draws and i secretly avoided lifting because i also didnt tell my job about the surgery. and the 12 hours isnt bad just take your breaks but be mindful of the lifting. i surprisingly didnt have issues pushing the cart around the hospital but definately didnt lift anyone.