I shall remember My devotee and take him back to My supreme abode!

“ Yadi vatadi doshena mad bhakto mam ”

“If My devotee is unable to remember Me at the time of death because of disturbances felt within the body at that time, then I shall remember My devotee and take him back to My supreme abode.”

– Varaha Purana

Although it is not considered good to die in a coma, for devotees it may still be a glorious way to go.

“If you practice, it is possible that when you are sleeping you will chant, because mind is not inactive even when you are sleeping. So if you become practiced up to the mind and intelligence platform of your life, then even when you are sleeping, even when you are dreaming, you will be chanting Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare.
And if this perfection is attained, then in the coma stage of life also, even if you cannot speak at the time of death, internally you will be able to chant Hare Kṛṣṇa mantra, and that will guarantee your transferring from this material world to the spiritual world. That is the process.” (SB class)

“Ordinary men, there is nothing to be lamented. This change of body is just like dress. But a devotee, his case is different. If he has finished his Kṛṣṇa consciousness, or at the time of being unconscious, in coma, he remembered Kṛṣṇa, then he has gone to Kṛṣṇa. ” (SB class)

“Sometimes, when a person is dying, he falls into a coma and lies unconscious. We do not know what kind of fearful test this person is undergoing. He may be dreaming so many things, or he may be crying. He cannot express what is going on. Those who are very sinful especially die in that way.” (TLK)