Irreversible cessation of brain-stem function

Absence of brain stem reflexes

  1. The pupils are fixed and do not respond to sharp changes in the intensity of incident light.
  2. There is no corneal reflex; care should be taken to avoid damage to the cornea.
  3. The oculo-vestibular reflexes are absent.
  4. No motor responses within the cranial nerve distribution can be elicited by adequate stimulation of any somatic area.
  5. There is no cough reflex response to bronchial stimulation by a suction catheter placed down the trachea to the carina, or gag response to stimulation of the posterior pharynx with a spatula.
  6. The process for testing the respiratory response to hypercarbia (apnoea test) should be the last brain-stem reflex to be tested and should not be performed if any of the preceding tests confirm the presence of brain-stem reflexes.

Repetition of testing See Fig 3.

  1. The diagnosis of death by brain-stem testing should be made by at least two medical practitioners who have been registered for more than five years and are competent in the conduct and interpretation of brain-stem testing. At least one of the doctors must be a consultant.
  2. Those carrying out the tests must not have, or be perceived to have, any clinical conflict of interest and neither doctor should be a member of the transplant team.
  3. Testing should be undertaken by the nominated doctors acting together and must always be performed on two occasions. A complete set of tests should be performed on each occasion, i.e., a total of two sets of tests will be performed.
  4. Doctor A may perform the tests while Doctor B observes; this would constitute the first set. Roles may be reversed for the second set. The tests, in particular the apnoea test, are therefore performed only twice in total.
  5. If the first set of tests shows no evidence of brain-stem function, there need not be a lengthy delay prior to performing the second set.
  6. A brief period will be necessary after reconnection to the ventilator to allow return of the patient’s arterial blood gases and baseline parameters to the pre-test state, rechecking of the blood sugar concentration and for the reassurance of all those directly concerned.
  7. Although death is not confirmed until the second test has been completed the legal time of death is when the first test indicates death due to the absence of brain-stem reflexes.

Fig 3: Procedure for Diagnosis & Confirmation of cessation of brain-stem function by neurological testing of brain-stem reflexes.

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