Spinal man after brain death. The unilateral extension-pronation reflex of the upper limb as an indication of brain death

[Irreversible brain death-Part 2. Spinalization phenomena]

Spinal automatisms and reflexes, peripheral neurogenic and myogenic reactions are common in patients with irreversible brain death. They are therefore compatible and are even understood by experienced investigators as confirmation of irreversible brain death. This article provides an overview of the phenomenology of irreversible brain death and discusses it from a neuropathological perspective. Furthermore, irreversible brain death is described in order to distinguish it from pathological movements and motor reactions in comatose patients or patients with disturbed consciousness due to severe brain disorders.

Factors Affecting the Time Taken to Determine Brain Death in Patients with Impending Brain Death

BACKGROUND AND PURPOSE

The increased demand for donor organs has made it crucial to keep the organs of patients with impending brain death (PWIBDs) suitable for transplantation during the process of determining brain death. This study aimed to identify the time taken to determine brain death (TT-BD) in PWIBDs and the associated influencing factors.

METHODS

This study analyzed data collected by the Korean Organ Donation Agency from 15 hospitals in the Yeongnam region of South Korea. There were 414 PWIBDs eligible for inclusion in this study. The data consisted of the TT-BD for PWIBDs and the potential variables influencing the TT-BD.

RESULTS

The mean age of the 414 PWIBDs was 48.9 years, and 120 of them were female (29.0%). The mean TT-BD was 8.5 days. The presence of spontaneous movements (SMs) and craniotomy significantly affected the TT-BD. The mean TT-BDs were 13.9 and 8.2 days in the PWIBDs with and without SMs, respectively, and 9.8 and 8.0 days in the PWIBDs with and without craniotomy, respectively.

CONCLUSIONS

The SMs in PWIBDs and a craniotomy performed immediately before starting the process of determining brain death seem to be related to lengthening the TT-BD.

Reflex and Spontaneous Movements in Adult Patients during the Process of Determining Brain Death in Korea

BACKGROUND

Brain death is a clinical diagnosis that implies irreversible loss of function of the entire brain, including the brainstem and both hemispheres. Based on previous reports, it is not rare for reflex and spontaneous movements to occur in patients during the process of determining brain death. However, reports of the frequency and common types of these movements vary from study to study. Thus, we evaluated adult patients with impending brain death in Korea to determine the frequency and characteristics of reflex and spontaneous movements.

METHODS

Brain dead patients who were admitted to 15 hospitals in the Yeongnam region (Southeast) of Korea were recruited prospectively from January 2013 to September 2016. All patients met the criteria for brain death as established by the Korea Medical Association. All body movements occurred during the process of diagnosing brain death and were assessed by physicians and trained organ transplant coordinators. The frequency and characteristics of these movements were identified and the demographic and clinical factors of impending brain dead patients with and without these movements were compared.

RESULTS

A total of 436 patients who met the criteria for brain death were enrolled during the study period. Of these patients, 74 (17.0%) exhibited either reflex or spontaneous movements. Of this subset, 45 (60.8%) exhibited reflex movements only, 18 (24.3%) exhibited spontaneous movements only, and 11 (14.9%) exhibited both reflex and spontaneous movements. The most common reflex movements were the flexor/extensor plantar response and spinal myoclonus. Of the 74 patients, 52 (70.3%) exhibited one movement of the same pattern and 22 (29.7%) exhibited two or more different movement patterns. In addition, 45 (60.8%) exhibited these movements only on a limited area of the body with the leg being most common (n = 26, 57.8%). Patients with hypoxic brain damage and a higher systolic blood pressure exhibited significantly more reflex or spontaneous movements.

CONCLUSION

Movements associated with brain dead patients are not rare and thus an awareness of these movements is important to brain death diagnosis. Physicians who perform brain death examinations should understand the frequency and characteristics of these movements to reduce delays in determining brain death.

Chronic Brain-Dead Patients Who Exhibit Lazarus Sign

Lazarus sign, a complex reflex movement of the upper limbs after brain death, is a rare occurrence. We report two patients who showed a Lazarus sign following a diagnosis of brain death. It has been accepted that cardiac arrest usually occurs within 1 week after brain death; however, the two patients described herein survived for over 100 days after brain death was diagnosed. This report is intended to examine the relationship between the Lazarus sign and long-term survival after brain death, as well as to share our rare experience.

Spinal Decerebrate-Like Posturing After Brain Death

Introduction:

Criteria for establishing brain death (BD) require absence of all brainstem-mediated reflexes including motor (ie, decerebrate or decorticate) posturing. A number of spinal cord automatisms may emerge after BD, but occurrence of decerebrate-like spinal reflexes may be particularly problematic; confusion of such stereotypic extension–pronation movements with brain stem reflexes may confound or delay definitive diagnosis of BD. We present a case in which we verified the noncerebral (ie, likely spinal) origin of such decerebrate-like reflexes.

Methods:

Case report and systematic review of literature.

Results:

A 63-year-old woman presented with large pontine hemorrhage and complete loss of cerebral function, including no motor response to pain. Apnea testing confirmed death by neurologic criteria. Thirty-six hours after BD declaration, during assessment for organ donation, she began to exhibit spontaneous and stimulus-induced stereotypic extension–pronation of the upper extremities. The similarity of these movements to decerebrate posturing prompted concern for retained brain stem function, but repeat neurological examination of cranial nerves and apnea testing did not reveal any cerebral responses. Electrocerebral silence on electroencephalogram and absent perfusion on nuclear medicine brain imaging further confirmed BD. Review of PubMed yielded 5 additional case reports and 4 cohorts describing cases of decerebrate-like extension–pronation movements presenting in a delayed fashion after BD.

Conclusion:

Extension–pronation movements that mimic decerebrate posturing may be seen in a delayed fashion after BD. Verification of lack of any brain activity (by both examination and multiple ancillary tests) in this case and others prompts us to attribute these movements as spinal cord reflexes and propose they be recognized within the rubric of accepted post-BD automatisms that should not delay diagnosis or necessitate confirmatory testing.

Analytic Reviews : Organ Procurement and Brain Death in Trauma Patients

The success rates and effectiveness of transplantation programs continue to increase, as does the need for cadaveric organs. Increasing organ procurement is a worthwhile goal that can be fully justified on economic, humanistic, and ethical bases. Although a great deal of progress has been made in terms of public and political awareness of organ procurement problems, additional changes and further education will be necessary before the number of cadaveric organs that are needlessly wasted can be reduced.

Management of patients with unsurvivable head in juries or patients who are candidates for organ donation is a complex task involving critical care management, the declaration of brain death, and the identification of, and request for, organ donation from next of kin. This process involves the coordinated efforts of neurosur geons, critical care specialists, social workers, and the transplant team coordinators in organ procurement pro grams. Patients are best managed in tertiary centers that have staffs with the expertise and interest in performing these tasks. The time to cardiac death in brain-dead pa tients is frequently short and is hastened by the develop ment of rapidly progressive derangements in gas ex change, fluid and electrolyte homeostasis, temperature regulation, coagulation, and cardiovascular function. Premature death under these circumstances continues to be a major reason for organ-procurement failure. Ag gressive monitoring and treatment of the multiple med ical problems encountered, however, may reduce the number of patients who die prematurely and thus in crease organ procurement rates.

Analytic Reviews : The Diagnosis of Brain Death in the Adult Patient

The biological tenet upon which brain death is founded is absolute. The brain's inability to undergo cellular divi sion ensures that once individual neurons die they can not be replaced. Extrapolating this to the total brain, once the entire brain is dead no recovery can occur, and the patient's family can be guaranteed of that fact. The clinician, therefore, is faced primarily with a diagnostic challenge in determining that brain death is indeed pres ent. The components, procedures, and limitations of that diagnostic process in the adult patient are the sub jects of this discussion.

Continuing Care of Multiorgan Donor Patients

Preserving the optimal function of donor organs must be the primary goal of physicians caring for patients who have been certified brain dead and from whom organs will be transplanted. During the hours before organ removal, several significant medical challenges may emerge. These challenges include restoration and maintenance of intravascular volume and cardiac output to assure adequate oxygen delivery to donor tissue; re suscitation of the patient from spontaneous cardiac ar rest ; evaluation and reversal of polyuria; management of poikilothermia and the effects of hypothermia; and treat ment of hypopituitarism and other possible changes in circulating hormones. Individual organ function and the interdependency among donor organs must be carefully monitored and balanced to assure that the recipient re ceives organs that have the best opportunity for optimal primary function. Care of the multiorgan brain dead pa tient and his or her family requires a multidisciplinary team skilled not only in the medical and surgical aspects of transplantation but also in the care of families who have suffered loss.

A new focus for patient care is appropriate after the decision has been made that a patient is brain dead and will become an organ donor. Because preser vation of brain function is no longer possible, treat ment priorities should shift to maximize perfusion and function of the donor organs. Through careful management of the donor patient, the recipient will receive organs that are less likely to undergo pri mary failure. This discussion will review the physio logical support necessary to sustain brain dead pa tients and to optimize donor organ function until organ removal is completed. It is assumed that indi vidual organs will be assessed and accepted or re jected for donation using criteria established by lo cal organ procurement teams. Such criteria will not be discussed here.

The brain dead organ donor presents a variety of management challenges (Table 1) that may extend over many hours while members of transplant teams and organ recipients are assembled and tis sue testing is completed. The responsibility for care may remain with the admitting physician or critical care medicine specialists, or it may be transferred to the transplant service. Coordination, however, remains the key to a successful outcome. The avail ability and interest of a knowledgeable physician to supervise the donor patient's care continues to be crucial because a variety of problems, each capable of rendering donor organs useless, may develop in the hours between brain death and organ removal.

Heart Transplantation

Although the number of available donor hearts severely limits the epidemiologic impact of heart transplantation on patients with heart failure, patients with end-stage heart failure unresponsive to medical management currently have no other viable alternatives. Destination therapy with a ventricular assist device is the closest toward approaching clinical reality but has been plagued with problems of infection and stroke. The purpose of this review is to summarize recent developments in the field that may broaden the clinical impact of heart transplantation. For example, novel methods of cardiac preservation are being designed to safely evaluate and utilize “extended criteria” donors. Surgical techniques and medical management have reduced the incidence of postoperative right heart failure, and immunosuppressive regimens promise to limit chronic graft vascular disease.

Hypothalamic-Pituitary Function in Brain Death: A Review

The Uniform Determination of Death Act (UDDA) states that an individual is dead when "all functions of the entire brain" have ceased irreversibly. However, it has been questioned whether some functions of the hypothalamus, particularly osmoregulation, can continue after the clinical diagnosis of brain death (BD). In order to learn whether parts of the hypothalamus can continue to function after the diagnosis of BD, we performed 2 separate systematic searches of the MEDLINE database, corresponding to the functions of the posterior and anterior pituitary. No meta-analysis is possible due to nonuniformity in the clinical literature. However, some modest generalizations can reasonably be drawn from a narrative review and from anatomic considerations that explain why these findings should be expected. We found evidence suggesting the preservation of hypothalamic function, including secretion of hypophysiotropic hormones, responsiveness to anterior pituitary stimulation, and osmoregulation, in a substantial proportion of patients declared dead by neurological criteria. We discuss several possible explanations for these findings. We conclude by suggesting that additional clinical research with strict inclusion criteria is necessary and further that a more nuanced and forthright public dialogue is needed, particularly since standard diagnostic practices and the UDDA may not be entirely in accord.

Brain Death Determination

In the United States, each year 1% to 2% of deaths are brain deaths. Considerable variation in the practice of determining brain death still remains, despite the publication of practice parameters in 1995 and an evidence-based guideline update in 2010. This review is intended to give bedside clinicians an overview of definition, the causes and pitfalls of misdiagnosing brain death, and a focus on the specifics of the brain death determination process.

Fasciculations in brain death

OBJECTIVES

Brain death is the colloquial name for human death determined by tests showing irreversible cessation of the clinical functions of the brain. Spontaneous and reflex movements have been described in brain death. The aim of this report is to describe a brain-dead patient with unusual motor movements.

DESIGN AND SETTING

The patient was followed and her motor movements were videotaped.

PATIENT

We report the presence of extensive and long-lasting fasciculations in a patient who fulfilled the criteria for brain death.

MEASUREMENTS AND MAIN RESULTS

We describe and show on videotape a brain-dead patient with rare motor movements.

CONCLUSION

We suggest that fasciculations outlined in this study has to be accepted as motor symptoms in brain death patients.

Maternal brain death--an Irish perspective

BACKGROUND

Brainstem death is a concept used in cases in which life-support equipment obscures the conventional cardiopulmonary criteria of death. Brainstem death during pregnancy is an occasional and tragic occurrence.

AIMS

To considerthe ethical, legal and medical issues raised by maternal brainstem death.

METHODS

Medline and Embase search.

RESULTS

The death of the mother mandates consideration of whether continuing maternal organ supportive measures in an attempt to attain foetal viability is appropriate, or whether it constitutes futile care. There is no theoretical limit to the duration of time for which maternal somatic function may be sustained. However, successful prolongation of maternal somatic function in pregnancies of less than 16 weeks gestation has not been reported to date. There is no legal imperative to continue maternal somatic support where there is little likelihood of a successful foetal outcome.

CONCLUSION

The difficult issues raised by maternal brainstem death mandates a consensus building approach to decision making in this context.

Maternal brain death and somatic support

Brain death is a concept used in situations in which life-support equipment obscures the conventional cardiopulmonary criteria of death, and it is legally recognized in most countries worldwide. Brain death during pregnancy is an occasional and tragic occurrence. The mother and fetus are two distinct organisms, and the death of the mother mandates consideration of the well-being of the fetus. Where maternal brain death occurs after the onset of fetal viability, the benefits of prolonging the pregnancy to allow further fetal maturation must be weighed against the risks of continued time in utero, and preparations must be made to facilitate urgent cesarean section and fetal resuscitation at short notice. Where the fetus is nonviable, one must consider whether continuation of maternal organ supportive measures in an attempt to attain fetal viability is appropriate, or whether it constitutes futile care. Although the gestational age of the fetus is central to resolving this issue, there is no clear upper physiological limit to the prolongation of somatic function after brain death. Furthermore, medical experience regarding prolonged somatic support is limited and can be considered experimental therapy. This article explores these issues by considering the concept of brain death and how it relates to somatic death. The current limits of fetal viability are then discussed. The complex ethical issues and the important variations in the legal context worldwide are considered. Finally, the likelihood of successfully sustaining maternal somatic function for prolonged periods and the medical and obstetric issues that are likely to arise are examined.

Undulating toe movements in brain death

For many years, death implied immobility. Nevertheless, there are anecdotal reports of spontaneous or reflex movements (SRMs) in patients with Brain death (BD). The presence of some movements can preclude the diagnosis of BD, and consequently, the possibility of organ donation for transplantation. McNair and Meador [(1992), Mov Dord7: 345-347] described the presence of undulating toe flexion movements (UTF) in BD patients. UTF consists in a sequential brief plantar flexion of the toes. Our aim was to determine the frequency, characteristics and predisposing factors of UTF movements in a prospective multicenter cohort study of patients with BD. Patients with confirmed diagnosis of BD were assessed to evaluate the presence of UTF using a standardized protocol. All patients had a routine laboratory evaluation, CT scan of the head, and EEG. Demographic, clinical, hemodynamic and blood gas concentration factors were analyzed. amongst 107 BD patients who fulfilled the AAN requirements, 47 patients (44%) had abnormal movements. UTF was observed in 25 (23%) being the most common movement (53%). Early evaluation (OR 4.3, CI95% 1.5-11.9) was a predictor of UTF in a multivariate regression model. The somato-sensory evoked potential (SSEPs) as well as brainstem auditory evoked potentials (BAEPs) did not elicit a cortical response in studied patients with UTF. This spinal reflex is probably integrated in the L5 and S1 segments of the spinal cord. Abnormal movements are common in BD, being present in more than 40% of individuals. UTF was the most common spinal reflex. In our sample, early evaluation was a predictor of UTF. Health care professionals, especially those involved in organ procurement for transplantation, must be aware of this sign. The presence of this motor phenomenon does not preclude the diagnosis of BD.

Facial myokymia in brain death

BACKGROUND

Brain death (BD) is the irreversible loss of all functions of the brain and brainstem. Spontaneous and reflex movements of the limbs have been described in this condition. However, facial myokymia (FM) in BD has not been previously reported. The origin of that motor phenomenon in alive patients is still uncertain, since supranuclear, nuclear and peripheral mechanisms have been proposed.

OBJECTIVE

We describe the presence of FM in a patient who fulfilled the criteria for BD. A 40-year-old-man had right-sided weakness and impaired consciousness. After 14 h admission, he fulfilled the criteria for BD. A CT scan of the head showed a large putaminal hemorrhage. The EEG was isoelectric. At that time, fine spontaneous twitches of the left cheek were noticed. They consisted of repetitive and rhythmic movements in groups of 3-5 lasting for < 5 s. These movements appeared every 2-10 min during 6 h.

DISCUSSION

Spinal reflexes have been described in BD. The presence of any movements other than the recognized reflexes may question this diagnosis and limit organ procurement for transplantation. The recognition of FM as an accepted movement in BD patients has practical and legal implications.

Course of neurological recovery and cerebral prognostic signs during cardio-pulmonary resuscitation

The recovery of cranial nerve reflexes was evaluated sequentially in time during the efforts at resuscitation in 111 victims of circulatory arrest of primary cardiovascular or pulmonary origin. Fifty-seven patients had some brain function when life support was initiated (Group I) while 54 had at first no such function (Group II). Recovery occurred in a fixed order, irrespective of the initial neurological status or subsequent outcome: spontaneous respiratory movements were either present or were the first function to return; thereafter followed pupillary light reflexes, coughing-swallowing, and ciliospinal reflexes, in that order. Orderly recovery was featured by a time-related return of reflexes and consciousness while abnormal courses were characterized by stagnation of the recovery process, lack of time-related return of and loss of function. Prognostic rules were similar for the two population groups. Reflex tests at 10-60 min of resuscitation differentiated patients who would regain consciousness from those remaining unconscious with sensitivities and specificities > or = 80. A positive pupillary response or coughing-swallowing at 10 min, or ciliospinal reflex at 20 min predicted return of consciousness with positive predictive values of 0.85-1.00 (prior odds 0.29) while negative tests at 20-30 min indicated failure of complete recovery with values of 0.94-100 (prior odds 0.89).

Novel actions of thyroid hormone: the role of triiodothyronine in cardiac transplantation

In clinical heart transplantation, the heart is procured from brain dead (BD) organ donors who acutely experienced a variety of critical illnesses. In all of these conditions, a profound derangement of the thyroid profile has been observed. Although the plasma levels of thyroid stimulating hormone (TSH) remain unchanged, there is a rapid decline in free triiodothyronine (FT3) levels (p < 0.0001) as well as an elevation of reverse triiodothyronine (rT3) (p < 0.001). Following induction of experimental brain death, the heart exhibits a progressive significant hemodynamic-biochemical deterioration (reduction of cardiac contractility, depletion of high energy phosphates, glycogen, and accumulation of tissue lactate). The administration of T3 to BD animals resulted in rapid reversal of the hemodynamic and metabolic derangements. The impact of T3 therapy to unstable human brain dead organ donors has resulted in rapid hemodynamic stability allowing significant reduction of inotropic support (p < 0.001). These hearts, following cardiac transplantation, exhibited excellent hemodynamic function in the recipients. The low FT3 state has also been observed during and following open heart surgery on cardiopulmonary bypass (CPB). Therefore, at the completion of the heart transplant procedure, T3 was also administered to the recipient to prevent relapse of the hemodynamic-metabolic abnormality observed in the donor. The impact of T3 therapy to initially unstable donors allowed for rapid inotropic reduction and recovery of the heart, thus enlarging the donor organ pool and improving the outcome of the recipients following cardiac transplantation.

Concepts and diagnosis of brain death

The different concepts of brain death are subject to controversial debate. It is outlined that only the whole-brain concept, that is the irreversible loss of all functions of the entire brain, is consistent with the death of man. Cortical death or brain-stem death should not be considered in this respect. The operational procedure for determining brain death is outlined with special regard to those cases in which a definite diagnosis cannot be made clinically. It is shown that apnea testing must be accompanied by blood-gas analysis, as it may take 15 min for the PaCO2 to achieve the desired level of 8 kPa. The problem with CNS-depressing drugs and their metabolites interfering with the clinical diagnosis--e.g. sedatives, barbiturates, opioids--is described, and it is stressed that, in these cases, the cerebral panangiography (digital subtraction angiography with catheter tip in the aortic arch) is the gold standard for the final and definite proof of brain death.

The undulating toe flexion sign in brain death

Brain-dead patients may exhibit gross spontaneous and reflex movements (e.g., Babinski sign, stereotypic flexion of one or more limbs, and Lazarus sign). We report three brain-dead patients who had unusual complex sequential movements of the toes. Undulating toe flexion was elicited by noxious stimuli to the lower extremities, and consisted of initial plantar flexion of the great toe, followed by sequential brief plantar flexion of the second, third, fourth, and fifth toes. The undulating toe flexion sign differs from previously described responses characterized by plantar flexion of the toes (e.g., Rosselimo's sign and the Mendel-Bechterew sign) in that it consists of complex patterned sequential movements of the digits rather than brief simultaneous flexion and/or fanning of the toes. Neurologists should be aware of this unusual finding, which should not preclude the diagnosis of brain death.

Hemodynamic responses to noxious stimuli in brain-dead organ donors

The case report presents evidence for the spinal origin of the marked hypertensive responses to noxious stimuli that may occur in organ donors who fulfill the commonly accepted criteria of brain death. Cardiovascular spinal reflex activity does not invalidate these criteria. For the first time, the catecholamine plasma concentrations have been determined during spinal pressor reflex activity. Circulating epinephrine increased more markedly than norepinephrine in both cases, rising to 4.7 and 44 times the baseline concentration respectively. The relation between plasma norepinephrine and epinephrine suggests involvement of the adrenal medulla in the reflex arc. The literature on spinal hemodynamic reflexes is reviewed.

Preserved spinal dorsal horn potentials in a brain-dead patient with Lazarus' sign. Case report

The case of a brain-dead patient with complex movements of the extremities (Lazarus' sign) is reported. This is the first description in the literature of short-latency somatosensory evoked potentials (SSEP's) following median-nerve stimulation by a noncephalic reference method. The scalp P14 wave (a far-field positivity with a peak latency around 14 msec that originates from the cervicomedullary junction) disappeared, and the spinal N13 wave (a near-field negativity with a 13-msec peak recorded on the posterior neck and generated by the cervical dorsal horn) was preserved. Respiratory-like movement was also seen in this case. The SSEP. findings support the hypothesis that both Lazarus' sign and respiratory-like movement have a spinal origin.

Organ procurement in patients with fatal head injuries. The fate of the potential donor

A 46-month, retrospective review of all victims of fatal head injury at a level 1 trauma center was undertaken to estimate donor organ availability, determine causes of procurement failure, and analyze the functional results of organs transplanted from this group of donors. Causes of procurement failure in 126 patients who died principally from their head injuries included failure of initial resuscitation (14%), ineligibility (28%), failure of physiologic support (14%), and denial of consent (20%). Of 73 eligible donors, 29 (41%) were able to donate one or more vascular organs (heart, liver, kidney). In only one instance was an eligible donor not appropriately identified as such. Failure of physiologic support to prevent early death (25%), and denial of consent (34%) were found to be the two major, potentially remediable causes of procurement failure in this series. Based on this data, an estimated 29 patients/million population/year will survive initially and meet all eligibility requirements for organ donation. Data on 47 kidneys transplanted from the donor group demonstrated a 77% overall graft survival rate at a follow-up period averaging 23 months. Prolonged donor hypotension, but not the use of high-dose vasopressors, adversely affected allograft survival. The current limitations of organ procurement in victims of fatal head injury stem from a limited ability to maintain cardiopulmonary function long enough for the procurement process to be completed and a high overall rate (46%) of denial of consent for organ harvest by next of kin.

Triiodothyronine in the recovery of stunned myocardium in dogs

Two groups of dogs were subjected to a 15-minute period of regional myocardial ischemia by snaring the left anterior descending coronary artery proximal to its first diagonal branch. After release of the snare, the dogs were given either placebo (group 1: n = 7) or triiodothyronine (T3) therapy (group 2: n = 6). The dose of T3 given was 0.2 microgram/kg at 30-minute intervals to a total of six doses. Plasma free T3 level fell significantly during the ischemic period in both groups and continued to fall after reperfusion in group 1. In both groups, cardiac function deteriorated significantly during the period of ischemia and rapidly returned to control level after reperfusion. After 90 minutes of reperfusion, however, deterioration of left ventricular function was observed in group 1 and was significantly worse than in group 2, in which hemodynamic function was maintained and, in fact, improved to levels superior to control. It is suggested that T3 therapy may be worthy of trial in patients in whom reperfusion of the myocardium takes place after a relatively short ischemic period (the "stunned myocardium").

Anaesthetic management of the brain dead for organ donation

An increasing number of anaesthetists is being called upon to manage organ donors during organ retrieval procedures. We briefly describe the technical aspects of the surgical procedure together with a guide to the anaesthetic management. The aims of the latter may be summarized as the "Rule of 100": systolic blood pressure greater than 100 mmHg, urine output greater than 100 ml.hr-1, PaO2 greater than 100 mmHg, haemoglobin concentration greater than 100 g.L-1. Common management problems (hypotension, arrhythmias, diabetes insipidus, oliguria, and coagulopathy) are discussed in detail. The intraoperative management of the brain-dead organ donor provides the anaesthetist with the challenge of a major surgical procedure in a subject with important physiological derangements.

Changes in spinal reflex excitability in brain-dead humans

The excitability of proprio- and exteroceptive spinal reflexes was monitored electrophysiologically and clinically during the occurrence of brain death (BD) in 8 patients. After a period of total reflex unresponsiveness, the soleus H reflex attained a steady-state excitability level in 2-6 h. The recovery cycle of this response regained its normal shape at 10-20 h. The threshold of the cutaneous reflex evoked in the biceps femoris by electrical stimulation of the sural nerve had become normal in 4-13 h, although the response displayed an abnormal multi-component pattern. Digital responses to mechanical stimulation of the foot sole were evident after 6-8 h. Knee and ankle jerks were never evoked during the time of monitoring. The time-courses of the changes in excitability were not directly correlated with the fall in the blood pressure which may occur during BD. It is concluded that the human spinal cord reacts to BD with a spinal shock, characterized by sequential recovery of reflex transmission. The overall timing of this process appears to be much shorter than that previously described for the spinal shock following traumatic transection of the cord, but the latter was never studied in the earliest phases.

Lazarus sign and extensor posturing in a brain-dead patient. Case report

A man was declared brain dead after having sustained a gunshot wound to the head. All clinical criteria for the diagnosis of brain death were met. The electroencephalogram was isoelectric, and four-vessel angiography demonstrated the absence of cerebral blood flow. However, stereotypic spontaneous movements were observed which persisted for several hours. The possible mechanism is discussed and a short review of the literature is given.

Viscero-somatic and viscero-visceral reflexes in brain death

Little is known about spinal visceral reflexes in brain-dead man, although they have been described in experimental animals. In 1983, 25 brain-dead individuals were observed during donor nephrectomy. It was confirmed that some of these donors, without higher centre modulation and not under significant pharmacological influence, had viscero-somatic motor reflexes and viscero-visceral cardiovascular reflexes.

Brain death

Following the research of Giessen Neurosurgery on primary and secondary lesions of the hypothalamo-pituitary system and the brainstem over a period of more than 30 years, cerebral failure and death does not represent a uniform syndrome but consists of several, well characterized syndromes of irreversible hypothalamo-pituitary, mesencephalic and bulbar failure. The specific syndromes are described in detail. The diagnosis is based on establishing complete irreversible damage of specific vital basal functions such as hypothalamo-pituitary transmission, water- and electrolyte metabolism, temperature regulation, circulation and respiration. The common feature of all types is the irreversible break-down of the complex central neurogenous and/or neurohumoral regulatory system. The permanent and irreversible loss of central regulation and modulation means at the same time the complete cessation of the specific human cortical function, the death of the whole brain. Only in bulbar failure with primary irreversible cessation of respiration artificial respiration can maintain the autonomous functions of the heart for a limited time. It is indicated when organ explantation is to be considered. Complete and irreversible isolated loss of cortical function abolishes the normal human life, but does not mean death of the remaining vegetating human being.

ABC of brain stem death. From brain death to brain stem death

Images

Clinical and anatomical observation of a patient with a complete lesion at C1 with maintenance of a normal blood pressure during 40 minutes after the accident

The authors report on their clinical observations concerning a patient with a complete spinal cord injury at the level of C1, followed by a cardiac hypoxic arrest, due to immediate respiratory paralysis after the accident. Normal cardiac activity was obtained as a result of rapid resuscitation measures, using only intubation and external cardiac massage without any drug administration. The blood pressure was maintained without any drugs at a level of 130 Torr during 40 minutes before it fell to a permanent level of 50--40 Torr on ventilation alone. The diagnosis during the first hours was believed to be that of an irreversible coma with no evidence of vertebral injury. The patient started to recover consciousness after a few days but died on the 15th day. The case is discussed in the light of the literature and of the recent physiological experiments concerning the rapid changes of blood pressure after spinal cord section in animals.

Natural history of global and critical brain ischaemia. Part III: cerebral prognostic signs after cardiopulmonary resuscitation. Cerebral recovery course and rate during the first year after global and critical ischaemia monitored and predicted by EEG and neurological signs

The monitoring and predictive value of the electroencephalography (EEG) and neurological signs was evaluated in 125 patients who had sustained critical brain ischaemia during circulatory arrest of primary cardiovascular aetiology. Cranial nerve areflexia with mydriasis or extension of the upper limb in response to cutaneous stimulation reliably indicated brain death and appearance of the flexion reflex or of intermittent spikes and sharp waves in the EEG predicted an unfavourable outcome; but other EEG configurations and nuerological signs per se were inaccurate variables to assess the outcome. By contrast, the recovery course and rate were accurately assessed by the time for appearance of cerebral functions; the caloric vestibular reflex, decorticate posturing, stereotypic reactivity, intermittent and continuous electrocortical activity were regained within ultimate time limits of 900, 540, 455, 450, and 1020 min, respectively, corresponding to the longest delay compatible with recovery of function at all, and within critical time limits of 165, 180, 180, 200, and 630 min, respectively, corresponding to the longest delay compatible with recovery of consciousness. Moreover, intermittent electrocortical activity, consciousness, speech and ability to cope with personal necessities were regained within supercritical time limits of 3, 47, 156, and 336 h, respectively, corresponding to the longest delay compatible with complete restoration of post-awakening faculties within 1 year of resuscitation. Prognosis was currently ascertained during the period of unconsciousness as cephalic reactivities, and electrocortical activities were regained in an exponential relationship to time. Bradycardia or asystole prior to resuscitation and metabolic acidosis, hypotensive heart failure, recurrent circulatory arrest and pneumonia thereafter influenced the cerebral recovery adversely.

Natural history of global and critical brain ischaemia. Part II: EEG and neurological signs in patients remaining unconscious after cardiopulmonary resuscitation

Of 125 patients who had no detectable cortical activity (DCA) on the electroencephalograph (EEG) immediately upon resuscitation from circulatory arrest of primary cardiovascular aetiology, 88 remained unconscious; these patients had their EEG and neurological status serially investigated until they died. Immediately upon re-establishment of circulation all cerebral functions could be absent; the brain death (irreversible loss of functions) was then signified by the appearance of poikilothermia, diabetes insipidus and reflex extension of the upper limb. Most often, some cranial nerve reflexes were present; the EEG configurations and related neurological signs then appeared in a sequence which resembled orderly postischaemic recovery: A phase without DCA was at first characterized by an exclusive presence of cranial nerve reflexes and then by the appearance of decerebrate posturing this phase was followed by another phase of intermittent cortical activity (ICA) with decorticate and stereotypic motor responses and a phase of continuous cortical activity (CCA) accompanied by stereotypic reactivity. These phases were most often incomplete due to failure of recovery of some cranial nerve reflexes or were abnormal due to the appearance of intermittent spikes and sharp waves. Progressive recovery could stagnate at any step and the cerebral functions be lost abruptly or gradually in reverse order of recovery. The decay was invariably due to cardiovascular or pulmonary complications. Brain autopsy revealed extensive neuronal loss and intravital autolytic changes in patients who had fulfilled clinical criteria of brain death for more than 72 h, but the histopathology showed no relationship to other clinical findings during the postischaemic course.