Thanatology: respirator brain: practice question

A Forensic Medicine question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Forensic Medicine · Thanatology: respirator brain

Sample item

A man kept on a ventilator for several days after brain stem death is autopsied. The brain is soft and friable and disintegrates when removed, although the rest of the body shows no decomposition. What is this finding?

AContusional necrosis after head injuryBCerebral abscess with liquefactionCRespirator brain from autolysis without perfusionDEarly putrefaction of the brain

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

C. Respirator brain from autolysis without perfusion

When intracranial pressure exceeds perfusion pressure after brain death, blood flow to the brain stops while the rest of the body is kept oxygenated. The brain then undergoes autolysis and becomes soft and liquefied, termed respirator brain. The body shows no general putrefaction.

Option by option

A. Contusional necrosis after head injury
Contusional necrosis is focal and linked to the site of impact.
B. Cerebral abscess with liquefaction
An abscess would be a focal, encapsulated pus collection, not a diffuse softening.
C. Respirator brain from autolysis without perfusion (correct)
Correct. Absent cerebral perfusion allows autolysis in an otherwise preserved body.
D. Early putrefaction of the brain
Putrefaction would show in the whole body, with green discolouration and gas, which is absent.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Forensic Medicine question

What is the answer to this Forensic Medicine question?

The best answer is C, Respirator brain from autolysis without perfusion. When intracranial pressure exceeds perfusion pressure after brain death, blood flow to the brain stops while the rest of the body is kept oxygenated.

Why is "Contusional necrosis after head injury" not the answer?

Contusional necrosis is focal and linked to the site of impact.

Why is "Cerebral abscess with liquefaction" not the answer?

An abscess would be a focal, encapsulated pus collection, not a diffuse softening.

Why is "Early putrefaction of the brain" not the answer?

Putrefaction would show in the whole body, with green discolouration and gas, which is absent.

What concept does this question test?

It tests Thanatology: respirator brain in Forensic Medicine. The brain then undergoes autolysis and becomes soft and liquefied, termed respirator brain. The body shows no general putrefaction.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Thanatology: respirator brain?

Learn postmortem changes with their timelines, and toxicology as poison, sign, test and antidote. Then use the flashcards and the other Forensic Medicine questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.