ABC of brain stem death. From brain death to brain stem death.
Authors: C Pallis
Journal: BMJ (1982)

Historical backgroundBrain death was first described clinically in 1959 when two French physicians' identified a condition they called "coma depasse"-literally, a state beyond coma.Twenty of their 23 patients were suffering from primary intracranial disorders and the other three from the cerebral sequelae of -; cardiorespiratory arrest.All the classic features of brain death are found in this early report.Articles published in the early 1960s already suggested that the cerebral circulation was "blocked" by raised intracranial pressure in most of these cases. .: .; ; *. .The report of the Ad Hoc Committee of the Harvard Medical School in yrcptivity ad OSnIVIIy y .19682 brought awareness of brain death to a much wider audience.The --i ^*i--~*~-a >-:Harvard criteria demanded that the patient should be unreceptive and 2; N je'mo h unresponsive, the most intensely painful stimuli evoking "no vocal or other ;-* .s-+ response, not even a groan, withdrawal of a limb or quickening of 3 Ap!noeQ (rrun 4tff > ,respiration."There had to be no movements during observation for one -' ' -f.9hour.Apnoea was to be confirmed by three minutes off the respirator (the 4 Absence o elicitable.reflexes .; centrality of apnoea, properly defined and tested for, had already been appreciated).The Harvard criteria also required that there should be "no val ri (at SjuVEEG.1mmf)eatl reflexes," the emphasis being on brain stem reflexes.A flat or isoelectric -~..l-s-e~c EEG electroencephalogram at high gain was of "great confirmatory value."All the tests were to be repeated at least 24 hours later, with no change in the.All e t-eabove t 5hci)btefrd findings.at leQst '21 h'*~rs JQteI" With no ellange *The report unambiguously proposed that this clinical state should be w * .s.,, -; ~^. . _accepted as death; recognised the moral, ethical, religious, and legal implications; and boldly saw itself as preparing the way "for better insight into all these matters as well as for better law than is currently applicable."A year later Beecher, the chairman of the Harvard committee, stated that this body was "unanimous in its belief that an electroencephalogram was not essential to a diagnosis of irreversible coma," although it could provide "valuable supporting data."3...m................Within three years of this radical yet humane proposal two neurosurgeons from Mlinneapolis made the challenging suggestion that "in patients with known but irreparable intracranial lesions" irreversible damage to the brain 0 ., ~, stem was the "point of no return."The diagnosis "could be based on clinical judgment."14p ig ' a ~The Minnesota workers introduced the notion of aetiological preconditions.(Twenty of their 25 patients had sustained massive craniocerebral trauma and the others were suffering from other primary irreversible damage to the intracranial disorders.)They emphasised the importance of apnoea to the determination of brain death; in fact, they insisted on four minutes of V ,. brain stem the point ofdisconnection from the respirator.They demanded absent brain stem no retUrn.~~~~~~reflexes., stated that the findings should not change for at least 12 hours., and emphasised that the electroencephalogram was not mandatory for the diagnosis.Their recommendations later became known as the MUinesota criteria and were to influence thinking and practice in the UK considerably.