Cerebrovascular Autoregulation Monitoring in the Management of Adult Severe Traumatic Brain Injury: A Delphi Consensus of Clinicians.

BACKGROUND: Several methods have been proposed to measure cerebrovascular autoregulation (CA) in traumatic brain injury (TBI), but the lack of a gold standard and the absence of prospective clinical data on risks, impact on care and outcomes of implementation of CA-guided management lead to uncertainty. AIM: To formulate statements using a Delphi consensus approach employing a group of expert clinicians, that reflect current knowledge of CA, aspects that can be implemented in TBI management and CA research priorities. METHODS: A group of 25 international academic experts with clinical expertise in the management of adult severe TBI patients participated in this consensus process. Seventy-seven statements and multiple-choice questions were submitted to the group in two online surveys, followed by a face-to-face meeting and a third online survey. Participants received feedback on average scores and the rationale for resubmission or rephrasing of statements. Consensus on a statement was defined as agreement of more than 75% of participants. RESULTS: Consensus amongst participants was achieved on the importance of CA status in adult severe TBI pathophysiology, the dynamic non-binary nature of CA impairment, its association with outcome and the inadvisability of employing universal and absolute cerebral perfusion pressure targets. Consensus could not be reached on the accuracy, reliability and validation of any current CA assessment method. There was also no consensus on how to implement CA information in clinical management protocols, reflecting insufficient clinical evidence. CONCLUSION: The Delphi process resulted in 25 consensus statements addressing the pathophysiology of impaired CA, and its impact on cerebral perfusion pressure targets and outcome. A research agenda was proposed emphasizing the need for better validated CA assessment methods as well as the focused investigation of the application of CA-guided management in clinical care using prospective safety, feasibility and efficacy studies.

Research priorities in neurocritical care.

This summary of the last session of the First Neurocritical Care Research Conference reviews the discussions about research priorities in neurocritical care. The first presentation reviewed current projects funded by the National Institute of Neurological Disorders and Stroke at the National Institutes of Health and potential models to follow including an independent Neurocritical Care Network or the creation of such a network with the goal of collaborating with already existing ones. Experienced neurointensivists then presented their views on the most common and important research questions that need to be answered and investigated in the field. Finally, utility of clinical registries was discussed emphasizing their importance as hypothesis generators. During the group discussion, interests in comparative effectiveness research, the use of physiological endpoints from monitoring and alternate trial design were expressed.

Report of a National Conference on Donation after cardiac death.

A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.

Changes in severe accidental tetanus mortality in the ICU during two decades in Brazil.

INTRODUCTION: Tetanus is still a significant health hazard in developing countries, with high associated mortality. OBJECTIVE: Describe the management of patients with severe tetanus in intensive care units (ICUs), in two different periods. SETTING: ICUs of two general hospitals. DESIGN: Concurrent cohort study. METHODS: Follow-up of all patients hospitalized with the diagnosis of severe tetanus in the ICUs from October 1981 to March 2001. We collected data prospectively, regarding the site of injury, clinical features, frequent clinical and infectious complications, concomitant illnesses, and mortality. The patients were divided into two groups according to the treatment protocol used; before 1993 and after 1993. RESULTS: There were 126 patients in group 1 (93 males) with a mean age of 39.0 +/- 18.8 years. There were 110 patients in group 2 (95 males) with a mean age of 48.4+/-17.8 years. Incubation period, onset period, and symptomatic period were higher in group 2 ( P < or = 0.02). The duration of neuromuscular junction blockade, benzodiazepine administration, mechanical ventilation, and ICU stay were longer in group 2, P < 0.001. Infectious complications were more frequent in group 2 ( P < 0.001). The mortality rate in group 1 was 36.5% and in group 2, 18.0% ( P = 0.002). Mortality was directly associated with symptomatic period, acute renal failure cardiac arrest and hypotension, and inversely associated with onset period in the multivariate analyses. CONCLUSIONS: The reduced mortality in severe accidental tetanus patients in group 2 is probably related to advances in ICU management, despite the higher incidence of infectious complications, which are probably related to the longer ICU stay.

Propofol and midazolam in the treatment of refractory status epilepticus.

PURPOSE: To explore outcome differences between propofol and midazolam (MDL) therapy for refractory status epilepticus (RSE). METHODS: Retrospective chart review of consecutive patients treated for RSE between 1995 and 1999. RESULTS: We found 14 patients treated primarily with propofol and six with MDL. Propofol and MDL therapy achieved 64 and 67% complete clinical seizure suppression, and 78 and 67% electrographic seizure suppression, respectively. Overall mortality, although not statistically significant, was higher with propofol (57%) than with MDL (17%) (p = 0.16). Subgroup mortality data in propofol and MDL patients based on APACHE II (Acute Physiology and Chronic Health Evaluation) score did not show statistically significant differences except for propofol-treated patients with APACHE II score > or = 20, who had a higher mortality (p = 0.05). Reclassifying the one patient treated with both agents to the MDL group eliminated this statistically significant difference (p = 0.22). CONCLUSIONS: In our small sample of RSE patients, propofol and MDL did not differ in clinical and electrographic seizure control. Seizure control and overall survival rates, with the goal of electrographic seizure elimination or burst suppression rather than latter alone, were similar to previous reports. In RSE patients with APACHE II score > or = 20, survival with MDL may be better than with propofol. A large multicenter, prospective, randomized comparison is needed to clarify these data. If comparable efficacy of these agents in seizure control is borne out, tolerance with regard to hemodynamic compromise, complications, and mortality may dictate the choice of RSE agents.

Central nervous system involvement in Rickettsial diseases.

The Rickettsia are obligate intracellular parasites that are usually spread to humans by insects and typically produce vasculitides. The prototypic rickettsial disorder in the United States is Rocky Mountain spotted fever (RMSF). The differential diagnosis of RMSF and related disorders includes other conditions that produce vasculitis, most importantly meningococcemia. The rickettsial disorders are usually treated effectively with tetracycline derivatives.

Management approaches to prolonged seizures and status epilepticus.

Status epilepticus (SE) treatment should proceed on four fronts: termination of SE, prevention of recurrence, management of potential precipitating causes, and management of SE complications and underlying conditions. The intensity of the treatment should reflect the risk to the patient from SE, and drugs likely to depress respiration and blood pressure should initially be avoided. The Veterans Administration cooperative trial showed that when treating overt SE, first-line treatment success rates were: lorazepam 64.9%; phenobarbital 58.2%; diazepam/phenytoin 55.8%; and phenytoin alone 43.6%. The aggregate response rate to second-line agents for patients who did not respond to first-line agents was 7.0%, and it was 2.3% for third-line agents, raising the question of the efficacy of a second and third drug. The recommended treatment for generalized convulsive SE is to begin with lorazepam. As a second-line agent, phenytoin or fosphenytoin, is still recommended if SE control is not achieved within 5 to 7 min. Fosphenytoin achieves a free phenytoin level of about 2 micro/mL in 15 min, as opposed to 25 min with phenytoin itself. Moreover, fosphenytoin is safer and, despite higher cost, it may be cost-effective. High-dose barbiturates, high-dose benzodiazepines, and propofol are employed for major treatment for refractory SE. Patients at this stage should undergo continuous electroencephalogram monitoring. Once SE is controlled, prevention of seizure recurrence should be individualized to each patient. The major complications of generalized convulsive SE (GCSE), rhabdomyolysis and hyperthermia, should be watched for and treated.

Status epilepticus in children and adults.

Status epilepticus (SE) in children and adults is one of the most common neurology problems confronting the intensivist. Recognition of SE is usually straightforward, but may be complicated by the effects of other diseases or therapies. Emergent treatment is necessary to prevent further brain damage. This article reviews protocols for standard treatments of SE patients and includes recommendations for the management of refractory SE.

Status epilepticus.

Generalised convulsive status epilepticus is a medical emergency. Knowledge of the pathophysiology of status epilepticus and the pharmacology of the medications used to treat it allow one to devise a rational protocol for management. Anticipation of medical complications facilitates intervention when required. Prognosis depends largely on the underlying causes.

Medical management of subarachnoid hemorrhage.

The medical management of the subarachnoid hemorrhage patient has changed considerably over the past two decades. The widespread acceptance of early aneurysm obliteration allows the aggressive prophylaxis and treatment of many of the serious complications of this condition. Recognition of cerebral vasospasm and the prevention of the delayed ischemic deficits it can produce are the cornerstones of critical care for these patients. Analysis of their fluid and electrolyte disturbances is complex, but important for the optimization of intravascular volume and consequent cerebral blood flow. Recognition of the numerous infectious and other medical complications that can befall these patients aids in the attempt to restore them to as normal a functional capacity as is possible.

Seizures.

The ICU patient who develops seizures presents diagnostic and therapeutic dilemmas for the physician. The diagnostic studies required vary with the underlying disorders of the patient and with the other therapies in progress. For both individual seizures and status epilepticus, electroencephalography is essential, and a brain imaging study is usually necessary. Other diagnostic testing depends on the clinical situation and the results of these initial studies. Therapy for a single seizure or a few seizures remains controversial. Management of the patient in status epilepticus should proceed along parallel approaches to terminating status epilepticus, preventing its recurrence and treating its complications. Lorazepam appears to be the initial drug of choice; phenytoin is commonly used as a second choice. Phosphenytoin will probably replace intravenous phenytoin in this role. Although phenobarbital has long been used as a third-line agent, its utility has fallen into question. Refractory status epilepticus can usually be controlled with extraordinary doses of midazolam, propofol, or pentobarbital. Patients requiring treatment for refractory status epilepticus require excellent, multidisciplinary critical care.

Altered mental status in thrombotic thrombocytopenic purpura is secondary to nonconvulsive status epilepticus.

Thrombotic thrombocytopenic purpura (TTP) is a syndrome with numerous neurological manifestations including altered mental status and seizures. At least 10% of the patients with TTP seen at our institution had nonconvulsive status epilepticus as a cause of or associated with their altered mental status. We propose that altered mental status secondary to nonconvulsive status epilepticus requiring electroencephalographic diagnosis and antiepileptic medication occurs in a substantial proportion of patients with TTP.

Status epilepticus.

Status epilepticus is defined as a condition characterized by epileptic seizure prolonged or repeated so as to produce a lasting epileptic state. It is estimated that status epilepticus occurs in 50,000 to 60,000 individuals in the United States, with one third to one half of episodes occurring in patients with established epilepsy.