Increased circulating Ia-bearing T cells in HBsAg-positive chronic active hepatitis

Brain death

Since the Harvard report of 1968, the concept of brain death has become widely recognized throughout the world. Most developed countries have accepted brain death as constituting death of the individual, and allow such patients to be used as ‘heart-beating’ organ donors. Although the US and most other countries accept a ‘whole-brain’ definition of brain death, the concept of brainstem death has been adopted in the UK. This article describes the UK diagnostic criteria in detail, and compares these with the criteria used in other countries. Management of the brain dead organ donor is described, and controversies relating to the concept of brain death are also discussed.

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.

Movements in brain death: a systematic review

Brain death is the irreversible lost of function of the brain including the brainstem. The presence of spontaneous or reflex movements constitutes a challenge for the neurological determination of death. We reviewed historical aspects and practical implications of the presence of spontaneous or reflex movements in individuals with brain death and postulated pathophysiological mechanisms. We identified and reviewed 131 articles on movements in individuals with confirmed diagnosis of brain death using Medline from January 1960 until December 2007, using 'brain death' or 'cerebral death' and 'movements' or 'spinal reflex' as search terms. There was no previous systematic review of the literature on this topic. Plantar withdrawal responses, muscle stretch reflexes, abdominal contractions, Lazarus's sign, respiratory-like movements, among others were described. For the most part, these movements have been considered to be spinal reflexes. These movements are present in as many as 40-50% of heart-beating cadavers. Although limited information is available on the determinants and pathophysiological mechanisms of spinal reflexes, clinicians and health care providers should be aware of them and that they do not preclude the diagnosis of brain death or organ transplantation.

The Lazarus phenomenon

Even though Lazarus phenomenon is rare, it is probably under reported. There is no doubt that Lazarus phenomenon is a reality but so far the scientific explanations have been inadequate. So far the only plausible explanation at least in some cases is auto-PEEP and impaired venous return. In patients with PEA or asystole, dynamic hyperinflation should considered as a cause and a short period of apnoea (30-60 seconds) should be tried before stopping resuscitation. Since ROSC occurred within 10 minutes in most cases, patients should be passively monitored for at least 10 minutes after the cessation of CPR before confirming death.

Some questions about brain death: a case report

A 13-year-old girl had an anaphylactic cardiac arrest with 45 minutes of resuscitation. After rewarming on day 3, a first examination was compatible with brain death, including an apnea test. Shortly thereafter, a stimulus to the trapezius muscle above the clavicles resulted in bilateral lower-limb withdrawal. A subsequent examination by another intensivist found, during vestibulo-ocular testing, bilateral lower-limb withdrawal. A radionuclide cerebral blood-flow test indicated no intracranial flow, and a computed tomography scan indicated diffuse severe cerebral edema. After these tests, stimulus to the trapezius muscle resulted in bilateral lower-limb extensor posturing. The next day, on repeated examination, the patient no longer had any response to stimulus, and was declared brain dead. This case raised two questions. Why should an intermittent lower-limb withdrawal response to supraclavicular stimulus be a more critical brain function, precluding a diagnosis of brain death (indicating that the patient has not lost integrative unity of the organism), than all other clinical and radiological findings? Was the withdrawal response of spinal origin or brainstem origin? How one chooses to interpret the withdrawal of lower limbs elicited by supraclavicular stimulus directly determines whether the patient in this case was dead.

Frequency of spinal reflex movements in brain-dead patients

Spontaneous and reflex movements may occur in brain-dead patients. These movements originate from spinal cord neurons and do not preclude a brain-death diagnosis. In this study, we sought to determine the frequency and characteristics of motor movements in patients who fulfilled diagnostic criteria for brain death. Patients admitted to our department between January 2000 and March 2003 and diagnosed as brain-dead were prospectively evaluated in terms of spinal reflexes. Clinical brain death was diagnosed according to our national law. We also prefer to document the diagnosis of brain death with an EEG and/or TCD. Spinal reflex movements were observed in 18 out of 134 (13.4%) brain-dead patients during the study period. Lazarus sign, the most dramatic and complex movement seen in brain-dead patients, was observed a few times in two patients during an apnea test, an oculocephalic test, after a painful stimulus, and after removal of a ventilator. The other reflex movements observed in our brain-dead patients were finger and toe jerks, extension at arms and shoulders, and flexion of arms and feet. The occurrence of spinal reflexes in brain-dead patients may certainly delay decision making, such as starting a transplantation procedure, because of difficulties in convincing the family or even a physician taking part in the diagnosis of brain death. An awareness of spinal reflexes may prevent delays in and misinterpretations of the brain-death diagnosis.

Complex spinal reflexes during transcranial Doppler ultrasound examination for the confirmation of brain death

OBJECTIVE

Complex sets of movements of the extremities can be seen in patients with brain death (BD), and are typically observed during apnea testing or removal of ventilatory support (also called the Lazarus sign). We here describe brain-dead patients who had not shown previous movements, even during apnea testing, but presented complex spinal reflexes during transcranial Doppler (TCD) examination elicited by neck flexion.

METHODS

We performed a prospective TCD study of patients with the clinical diagnosis of BD.

RESULTS

Four (2.5%) of 161 brain-dead patients presented complex spinal reflexes exclusively during TCD examination. TCD showed vertebro-basilar circulatory arrest in all four. Their systolic blood pressure was significantly lower than that of brain-dead patients not presenting movements during TCD examination.

CONCLUSIONS

Hypotension and mechanical stimulation play a role in the pathophysiology of complex spinal reflexes present in BD, which are not exclusively seen in terminal hypoxia. Intensive care personnel and neurologists who perform TCD to confirm BD should be aware of these movements.

Head turning in brain death

Criteria for determination of brain death in adults have been defined. Spinal cord reflexes may persist after brain death. We present the case of a brain dead patient who had a complex spinal automatism resulting in head shaking and arm extension. The report reviews guidelines for the diagnosis of brain death and discusses complex spinal cord reflexes in brain dead patients.

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.

Immunological studies in patients with HBsAg-positive chronic active hepatitis--spontaneous lymphocyte transformation and natural killer cell activity

The present study was to address the nature of cells which are responsible for enhanced spontaneous lymphocyte transformation (SLT) observed in patients with HBsAg-positive chronic active hepatitis (CAH). The subjects consisted of 34 cases with HBsAg-positive CAH (group I), 31 HBsAg carrier (group II), and 27 normal persons (group III) who had no serological evidence of hepatitis B virus (HBV) infection. SLT values and the number of cells bearing HLA-DR antigens in group I (1021.45±276.40 cpm, 36.94±4.90%) were significantly (p<0.01) elevated as compared to group II (103.74±30.44 cpm, 13.26± 4.72%) and III (118.92 ± 30.84 cpm, 14.93±5.10%), but there was no difference of the number of the IL-2 receptor-bearing cells among each groups. Though natural killer (NK) cell activity in both group I (65.42±15.77%) and II (59.14±14.89%) were significantly enhanced as compared to group III (46.25±20.20%), there was no difference in between group I and II. These findings indicate that the cells bearing HLA-DR antigen, but not NK cells, are responsible for the enhanced SLT in patients with CAH.