When Are You Ready to Pull the Plug against the Wishes of the Family?

On his blog, End of Life - Thoughts from an MD, Dr. Jim deMaine describes a recent case in which a conflicted family could not reach a treatment decision.  So, the patient with metastatic cancer spent three weeks in the ICU.  Her heart then stopped "and the nurses, much against their wishes, had to perform fruitless CPR. Mary thus died in a traumatic way, ribs broken from chest compressions, suffering the kind of technological imperative that's sarcastically referred to by the staff as 'medical last rites.'"  Dr. deMaine also asks how the case might have reached a better resolution, for example, through unilateral withdrawal.