Lal,
Thank you for these links, they do help to clarify a bit more. My confusion wasn’t about the concept of what is or isn’t an akusala anantariya kamma; I know that the workings of kamma is a complex subject. I was hoping to shed some light on the specific situation I was describing. The monk that I mentioned (the abbot) was adamant that a person must not “pull the plug” on an aging parent who is on life support and that doing so constitutes an akusala anantariya kamma and the person will go to Avecii hell. I’m not sure if he also meant that you must unequivocally put an aging parent on life support, because sometimes things get lost in translation between us. I disagree with him that either action constitutes an akusala anantariya kamma for 2 reasons:
1) the intention isn’t to kill and
2) there isn’t anyone doing any real “killing”; the person on life support is going to die on their own due to natural causes and their life is being prolonged in an unnatural way
Ultimately I suppose it’s just a niggling question that may not be possible to answer in a way that is 100% precise, and the noble thing to do is to take care of the person for as long as possible.