Death Rattle

Widespread understanding of the significance of the death rattle has led to its common use in literature.

She sank more and more into uneasy delirium. At times she shuddered, turned her eyes from side to side, recognized everyone for a minute, but at once sank into delirium again. Her breathing was hoarse and difficult, there was a sort of rattle in her throat.
— Fyodor Dostoevsky, Crime and Punishment

In common parlance we call it a "death rattle." It is one of those terms that through use has passed into the realm of fantasy so that many no longer believe it is an actual biological phenomenon. In fact, it is. Forensics experts tell us that the death rattle is the result of involuntary spasms in the vocal box brought on by the increased acidity in the blood following death. The noise itself is alternately described as a loud bark or whooping rasp emitted by a victim sometime after death.
— Steve Martini, The Judge

"If we are really dying, let us hear the rattle in our throats and feel cold in the extremities; if we are alive, let us go about our business."
— Henry David Thoreau, Walden

Presently his fingers began to pick busily at the coverlet, and by that sign I knew that his end was at hand. With the first suggestion of the death rattle in his throat he started up slightly, and seemed to listen; then he said:
"A bugle?...It is the king! The drawbridge, there! Man the battlements!—turn out the—"
He was getting up his last "effect"; but he never finished it.
— Mark Twain, A Connecticut Yankee in King Arthur's Court.

"Next morning, around six o'clock, the servant entered the room with a candle. He found his master lying on the floor, the pistol beside him, and blood everywhere. He called, he touched him; no answer came, only a rattling in the throat."
— Johann Wolfgang von Goethe, "The Sorrows of Young Werther"

"Life, like a child, laughs, shaking its rattle of death as it runs."
— Rabindranath Tagore

"I think I may have dropped off into a light sleep, but my senses were still wide awake, and I suddenly startled into intense consciousness by a hurried, angry sound, the most awe-inspiring sound anyone can hear, the Death Rattle." — W. Somerset Maugham "The Razor's Edge"

"...but the baby's crying, and its death rattle were heard, and they were discovered."
— Wladyslaw Szpilman "The Pianist"

http://en.wikipedia.org/wiki/Death_rattle