Spawk
You can always drill. Worst case is that as soon as you loss the mud circulation,is that you pump down cement!!!
Or drill with air so you have no mud or drill with casing as the drill string.
If you can imagine a way of doing it then the oil industry has used that method.
cheers
PC43
PS Lost circulation a pain but you can cope with it. Conversly it give you a very good flow rate.