Brainstem encephalitis imitating brain death

Misinterpretations of Guidelines Leading to Incorrect Diagnosis of Brain Death: A Case Report and Discussion

Guidelines describe the process necessary for the diagnosis of brain death. We present a case of a 3-month-old former 36-week-gestation infant after a prolonged out-of-hospital cardiac arrest of 37 minutes who was clinically diagnosed as brain dead at 120 hours after the event. Unusual findings included a normal slightly sunken anterior fontanelle, normal cerebral blood flow perfusion scan at 73 hours after the event, only localized parieto-temporal edema on the latest computed tomographic (CT) scan of the brain at 48 hours after the event, and discussion of whether nonconvulsive seizures could have confounded the examination for brain death. In light of these unusual findings, we discuss and highlight what may be common misinterpretations of brain death guidelines that led to the mistaken diagnosis of death (as opposed to severe neurologic injury) in this child.

What to exclude when brain death is suspected

BACKGROUND

With advances in critical care and organ donation, diagnosis of brain death is gaining importance. We aimed to assess potential brain death confounders from the literature, elucidating clinical presentation and diagnostic approaches in these cases.

METHODS

PubMed and Embase were screened using 37 predefined search terms to identify suitable articles reporting cases, case series, or cohort studies in adults.

RESULTS

Out of 4769 articles, 40 case reports or case series describing 45 patients with 19 critical conditions were identified. Mortality was 11% and full recovery 33%. Intoxications (42%; mainly anti-seizure drugs and baclofen) and polyneuritis (37%) were most frequent. Brainstem reflex tests were reported in 96%, apnoea test in 16% and ancillary tests in all but one patient. Full recovery mainly occurred with intoxications. Quality of evidence regarding frequency of confounders is very low and risk of bias high.

CONCLUSIONS

Brain death confounders are infrequently reported and formal studies are lacking. Mainly younger patients with polyneuritis and intoxications are described. As outcome, especially in the latter, is often favourable, high awareness and strict adherence to guidelines is crucial. The importance of identifying pathologies compatible with extensive and irreversible brain damage before proceeding to diagnostic tests should be emphasized.

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.

Variability among hospital policies for determining brain death in adults*

OBJECTIVE

In the absence of federal requirements or state statutes, criteria to certify brain death are specified by medical staff and administrative policies in individual hospitals. Variability among such policies may allow inconsistency in the declaration of death by neurologic criteria. Our intent was to partially quantify diversity among hospital standards used in brain death certification.

DESIGN

Survey.

SETTING

Six hundred randomly selected hospitals.

PATIENTS

None.

INTERVENTIONS

A survey was conducted of 600 hospitals randomly selected from the American Hospital Association registry representing 200 hospitals each of <300 beds, 300-500 beds, and >500 beds. One hundred six policies submitted by these institutions comprised the final study group. Policies were reviewed for criteria of interest and were compared against variables recommended by the American Academy of Neurology.

MEASUREMENTS AND MAIN RESULTS

Significant variability in policy criteria was found compared with the American Academy of Neurology and other authoritative standards. Differences were greatest in specifying conditions to be excluded before testing and in specific testing methods during a detailed physical examination. The few differences noted between larger vs. smaller hospitals most likely reflect greater availability of resources in larger institutions.

CONCLUSIONS

Differences among hospital policies for certification of brain death may permit variability among hospitals throughout the United States in the pronouncement of death by neurologic criteria. Standardization and enforcement of policies that ensure the highest possible accuracy should be considered.

Brain death: resolving inconsistencies in the ethical declaration of death

PURPOSE

The first criteria for the determination of brain death were developed in 1968 in part to address concerns that had arisen with the retrieval of organs for transplantation. Despite over 30 years of application, some professional and public doubt persists over the validity of the theoretical construct underlying this method of determining death. Our review will address historical perspectives on the development of brain death criteria, and inconsistencies in current clinical criteria.

METHOD

Narrative review from selected MEDLINE references and other published sources.

PRINCIPLE FINDINGS

The primary construct of the determination of death is that either cardiopulmonary or neurological function irreversibly ceases. However, there is inconsistency in the neurological criteria for death between jurisdictions, between patient populations, and in the use of confirmatory tests. These inconsistencies may cause concern in the public or profession about the validity of the determination of death by neurological criteria.

CONCLUSIONS

Organ transplantation is premised on professional and public acceptance that the donor is dead. Given that the criteria for brain death or their application remain variable, we suggest that it is reasonable to consider a national consensus to address these inconsistencies. Alternatively, the standard use of confirmatory radiographic testing prior to the retrieval of organs from donors who meet clinical brain death criteria should be considered to provide conclusive evidence of permanent and irreversible loss of brain function.

Clinical deterioration in Bickerstaff's brainstem encephalitis caused by overlapping Guillain-Barré syndrome

A 37-year-old man developed an acute encephalitic condition after respiratory infection. His condition rapidly deteriorated, and he experienced ophthalmoplegia, tetraplegia, loss of brainstem reflexes and deep tendon reflexes, and deep coma. Electrophysiological evaluations indicated involvement of the peripheral nerve as well as the brainstem. Follow-up studies found acute progression of peripheral nerve damage. Serum anti-GQ1b IgG antibody was present. The initial condition was diagnosed as Bickerstaff's brainstem encephalitis, and subsequent overlapping of Guillain-Barré syndrome probably was responsible for the clinical deterioration. When unusual worsening is observed in clinically suspected encephalitis, neurologists must take into account the possibility of associated Guillain-Barré syndrome and related disorders.

Role of short latency evoked potentials in the diagnosis of brain death

OBJECTIVE

The aim of this study is to confirm the effectiveness of auditory brain-stem responses (ABRs) and somatosensory evoked potentials (SEPs) in the diagnosis of brain death (BD).

METHODS

ABRs and SEPs were recorded at the same session in 130 BD patients (age range 8-77 years, 81 male and 49 female). Twenty-four cases were submitted to serial recordings from preterminal conditions through BD.

RESULTS

ABRs were absent in 92 cases (70.8%), only waves I or I-II were present in 32 cases (24.6%), while in the remaining 6 patients (4.6%) waves V and/or III were still present, excluding the death of the brain-stem. In 4 cases (3.1%) SEPs showed the absence of all components following the cervical N9, preventing the diagnosis of BD. Among 126 cases (96.9%) with preserved cervical N9-N13 SEPs confirmed the absence of brain-stem activity in 122 cases (93.7%), in whom no waves following P11 or P13 were recordable. SEPs excluded the diagnosis of BD in the remaining 4 cases (3.2%) showing preserved P14 and/or N18. In all pre terminal patients the far-field P14-N18 were present, and their disappearance was closely related to the onset of BD.

CONCLUSIONS

The combined us of ABRs and SEPs was able to confirm BD in almost all patients, providing an objective confirmation of the diagnosis, and to exclude it in 7 cases, thus improving the reliability of diagnosis.