Subtitled Understanding the special awareness, needs, and communications of the dying, this uses anecdotes to illustrate a set of general observations about the dying and the living.
Slow dying, as opposed to death by heart attack or accident, often follows a common pattern near the end. Some of these, such as unability to drink or the "death rattle" are more frightening to the family than painful to the dying. The family and the dying frequently react somewhere along Kubler-Ross' sequence: Denial, Anger, Bargaining, Depression, Acceptance--though they don't always "follow the sequence."
The authors' main contribution is to emphasize the need to listen carefully to the dying to discover what they are trying to say. People sometimes feel the need to wrap up their affairs, say goodbyes, reconcile with estranged family, or offer some encouragement themselves. Unfortunately, near the end, clear communication can become difficult. Probably most of us have been in the situation of wanting to say something, but, having forgeten the right word, trying to use a phrase that almost fits, or even trying to use some simile instead of clear prose. Apparently the dying are more aware of what is going on around them than one might expect given the closed eyes and lack of reaction.
If we pay careful attention to what they say, we can sometimes figure out what they mean despite some confusion. Some things are fairly clear: a man who laments that the trolley won't stop for him seems to be wondering why it is taking so long to die. Mentioning "Dad" in the middle of otherwise incomprehensible mumbles might mean that the woman wants to see her estranged father before she dies.
Or, of course, it might not. You have to know the person and their situation fairly well to figure out something like that.
The authors suggest that some people can "let go" at will. This is plausible: as the body begins shutting down functions, you might become more aware of the remaining ones--there's less distraction. And if with awareness of the action comes a little control, letting go seems more possible. We can all recall people who died after some milestone: Charles Schultz died days after his last Peanuts strip.
Some people want family around, while others, satisfied that they are loved, prefer not to be a bother and die when nobody is around. The authors say that many people blame themselves for not being there: "I just stepped out for a minute and he was gone!" Maybe the deceased wanted it that way.
Summary: The dying quite likely know what's going on (hearing is one of the last things to go), and you should pay attention to what they're saying. It may be in fragments, or even symbolic, but hear them out.