Imminent brain death: point of departure for potential heart-beating organ donor recognition

Abstract

Purpose: There is, in European countries that conduct medical chart review of intensive care unit (ICU) deaths, no consensus on uniform criteria for defining a potential organ donor. Although the term is increasingly being used in recent literature, it is seldom defined in detail. We searched for criteria for determination of imminent brain death, which can be seen as a precursor for organ donation.

Methods: We organized meetings with representatives from the field of clinical neurology, neurotraumatology, intensive care medicine, transplantation medicine, clinical intensive care ethics, and organ procurement management. During these meetings, all possible criteria were discussed to identify a patient with a reasonable probability to become brain dead (imminent brain death). We focused on the practical usefulness of two validated coma scales (Glasgow Coma Scale and the FOUR Score), brain stem reflexes and respiration to define imminent brain death. Further we discussed criteria to determine irreversibility and futility in acute neurological conditions.

Results: A patient who fulfills the definition of imminent brain death is a mechanically ventilated deeply comatose patient, admitted to an ICU, with irreversible catastrophic brain damage of known origin. A condition of imminent brain death requires either a Glasgow Coma Score of 3 and the progressive absence of at least three out of six brain stem reflexes or a FOUR score of E(0)M(0)B(0)R(0).

Conclusion: The definition of imminent brain death can be used as a point of departure for potential heart-beating organ donor recognition on the intensive care unit or retrospective medical chart analysis.

Fig. 1

Description of Full Outline of UnResponsivenes (FOUR) score. Eye response: E4 eyelids open or opened, tracking or blinking to command; E3 eyelids open but not tracking; E2 eyelids closed but open to loud voice; E1 eyelids closed but open to pain; E0 eyelids remain closed with pain. Motor response: M4 thumbs-up, fist or peace sign; M3 localising to pain; M2 flexion response to pain; M1 extension response to pain; M0 no response to pain or generalised myoclonus status. Brainstem reflexes: B4 pupil and corneal reflexes present; B3 one pupil wide and fixed; B2 pupil or corneal reflexes absent; B1 pupil and corneal reflexes absent; B0 absent pupil, corneal and cough reflex. Respiration pattern: R4 not intubated, regular breathing pattern; R3 not intubated, Cheyne-Stokes breathing pattern; R2 not intubated, irregular breathing; R1 breathes above ventilatory rate; R0 breathes at ventilator rate or apnea

Fig. 2

Flowchart of potential organ donors