The Role of Magnetic Resonance Imaging in the Prediction of Minimally Conscious State After Traumatic Brain Injury.

OBJECTIVE: To establish a simple and feasible model of magnetic resonance imaging (MRI) for prediction of minimally conscious state in unconscious patients (≥2 weeks) after severe traumatic brain injury (TBI). METHODS: MRI examinations were performed in 73 patients 4.5 weeks ± 1.6 (range, 2-8 weeks) after TBI. Brain lesions on MRI, age, sex, cause of injury, Glasgow Coma Scale (GCS) score, and decompressive craniectomy were retrospectively analyzed. Outcome was assessed at 12 months from the onset of TBI. RESULTS: Of 73 patients, 39 were minimally conscious and 34 were unconscious at the endpoint. Binary logistic regression demonstrated that cause of injury (P = 0.036), GCS score (P = 0.011), and lesions of the thalamus (P = 0.002) and brainstem (P = 0.012) shown on MRI were closely associated with the outcome of minimally conscious state. The overall correct prediction of the logistic model was 90.4%. CONCLUSIONS: The combination of MRI findings and other clinical data offers neurosurgeons substantial information about primary and secondary injuries of the patients with TBI, which allows a more accurate prediction of prognosis than a single GCS score or MRI findings alone. The regression model established in this study is simple and effective in predicting long-term unconscious state and minimally conscious state in patients after severe TBI.

Cardiac arrest and post resuscitation of the brain.

Primary out-of-hospital cardiac arrest in childhood is rare but survival is a little better for children than for adults, although the prognosis for infants is very poor. Hypoxic-ischaemic encephalopathy after in-hospital cardiac arrest in children undergoing complicated treatment for previously untreatable conditions is now a common problem and is probably increasing. An additional ischaemic insult worsens the prognosis for other encephalopathies, such as that occurring after accidental or non-accidental head injury. For near-drowning, the prognosis is often good, provided that cardiopulmonary resuscitation (CPR) is commenced immediately, and the child gasps within 40 minutes of rescue and regains consciousness soon afterwards. The prognosis is much worse for the nearly drowned child admitted to casualty or the emergency room deeply unconscious with fixed dilated pupils, requiring continuing CPR and with an arterial pH <7, especially if there is little recovery by the time of admission to the intensive care unit. The use of adrenaline, sodium bicarbonate and calcium appears to worsen prognosis. Neurophysiology, specifically serial electroencephalography and evoked potentials, is the most useful tool prognostically, although neuroimaging and biomarkers may play a role. In a series of 89 patients studied after cardiac arrest in three London centres between 1982 and 1985, 39% recovered consciousness within one month. Twenty seven percent died a cardiac death whilst in coma, and the outcome in the remainder was either brain death or vegetative state. EEG and initial pH were the best predictors of outcome in this study. Seizures affected one third and were associated with deterioration and worse outcome. The advent of extracorporeal membrane oxygenation (ECMO) and the positive results of hypothermia trials in neonates and adults have rekindled interest in timely management of this important group of patients.

Prognostication after cardiac arrest and hypothermia: a prospective study.

OBJECTIVE: Current American Academy of Neurology (AAN) guidelines for outcome prediction in comatose survivors of cardiac arrest (CA) have been validated before the therapeutic hypothermia era (TH). We undertook this study to verify the prognostic value of clinical and electrophysiological variables in the TH setting. METHODS: A total of 111 consecutive comatose survivors of CA treated with TH were prospectively studied over a 3-year period. Neurological examination, electroencephalography (EEG), and somatosensory evoked potentials (SSEP) were performed immediately after TH, at normothermia and off sedation. Neurological recovery was assessed at 3 to 6 months, using Cerebral Performance Categories (CPC). RESULTS: Three clinical variables, assessed within 72 hours after CA, showed higher false-positive mortality predictions as compared with the AAN guidelines: incomplete brainstem reflexes recovery (4% vs 0%), myoclonus (7% vs 0%), and absent motor response to pain (24% vs 0%). Furthermore, unreactive EEG background was incompatible with good long-term neurological recovery (CPC 1-2) and strongly associated with in-hospital mortality (adjusted odds ratio for death, 15.4; 95% confidence interval, 3.3-71.9). The presence of at least 2 independent predictors out of 4 (incomplete brainstem reflexes, myoclonus, unreactive EEG, and absent cortical SSEP) accurately predicted poor long-term neurological recovery (positive predictive value = 1.00); EEG reactivity significantly improved the prognostication. INTERPRETATION: Our data show that TH may modify outcome prediction after CA, implying that some clinical features should be interpreted with more caution in this setting as compared with the AAN guidelines. EEG background reactivity is useful in determining the prognosis after CA treated with TH.

[The brain hypothermia therapy for prevention of vegetation after severe brain injury].

We have presented a new concept of brain hypoxia oriented brain hypothermia treatments. All severe brain injury patients (148 cases) were GCS < 6. The masking brain hypoxia by brain thermo pooling, catecholamine surge induced cardiac dysfunction and intestinal vasodilatation, reduction of Hb-2.3 diphosphoglyserate were major target of initial treatment. These specific brain hypoxia was only controlled by brain hypothermia (34-32 degrees C), oxygen delivery > 800 ml/min. and AT-III > 100%. 2. The brain hypothermia were very successful to prevent masking brain hypoxia, selective radical attack to A10 dopamine nervous system, and brain edema. However, metabolic shift to lipid metabolism and lower growth hormone related immune crisis were recorded as a negative factors. Clinical results were so advanced. The mortality were 44 in 148 cases (30%), good recovery were 59 in 148 cases (40%), mild disability were 20 in 148 cases (13%) and vegetate state were only 15 in 148 cases (10%). The combination of brain hypothermia and replacement of cerebral dopamine were very successful to prevent the vegetation in severe brain injury.