Acta neurochirurgica. Supplement
-
Acta Neurochir. Suppl. · Jan 1998
Multimodal hemodynamic neuromonitoring--quality and consequences for therapy of severely head injured patients.
Fifty-five head injured patients (GCS < 8) were studied at an average of 7.5 +/- 3.4 days on the ICU to check quality of hemodynamic monitoring and the consequences for therapy. Multimodal neuromonitoring included intracranial pressure (ICP), mean arterial pressure (MAP), cerebral perfusion pressure (CPP), endtidal CO2 (EtCO2) as well as brain tissue--pO2 (p(ti)O2), regional oxygen (rSO2) and jugular venous oxygen saturation (SjO2). Regional p(ti)O2 as well as global SjO2 were sensitive technologies to detect hemodynamic changes. ⋯ Longterm-measurements of rSO2 using near infrared spectroscopy reached, if possible, a restricted reliability (good data quality up to 70%) and sensitivity in comparison to p(ti)O2. Especially p(ti)O2 enabled detection of critical p(ti)O2 (< 15 mm Hg) in up to 50% frequency during the first days after trauma and a second peak after day 6 to 8 according to evidence of CPP insults. Knowledge of baseline p(ti)O2 and CO2-reactivity allowed minimizing risk of ischemia by induced hyperventilation and improvement on cerebral microcirculation after mannitol administration could be individually recognized.
-
Acta Neurochir. Suppl. · Jan 1998
Relationship of neuron specific enolase and protein S-100 concentrations in systemic and jugular venous serum to injury severity and outcome after traumatic brain injury.
Neuron specific enolase (NSE) and protein S-100 have previously been described as markers of brain injury. We aimed to discover whether concentrations of either were raised in arterial and jugular venous serum after traumatic brain injury, and whether serum profiles were related to injury severity and neurological outcome. We recruited 22 patients with a traumatic brain injury who were admitted to the intensive care unit. ⋯ There was a small, but significant difference between jugular venous and arterial concentrations of S-100 (p = 0.022). High NSE and S-100 concentrations were significantly related to poor neurological outcome (p = 0.004 and p < 0.001 respectively). Both serum NSE and S-100 may be of some value in helping to predict outcome after a traumatic brain injury.
-
Acta Neurochir. Suppl. · Jan 1998
Effects of systemic hypothermia and selective brain cooling on ischemic brain damage and swelling.
The present study investigates the neuroprotective effects of temporary mild systemic hypothermia and selective brain cooling against focal cerebral infarction in the rat and the changes of cortical blood flow, and compares these two treatment modalities. In permanent middle cerebral artery (MCA) model, the treatments were induced 15 min following the artery occlusion. The animals were kept at the desired rectal or brain temperature (about 32 degrees C) for 30 min; (each, n = 6) and for 1 hr (each, n = 6), and then allowed to rewarm spontaneously, whereas control animals were kept at normothermia throughout the experiment. ⋯ However, in the selective brain cooling, the reduced blood flow increased from 40% to 70% of baseline value while the brain was rewarmed. The present study indicates that mild systemic hypothermia has much stronger protective effects against focal cerebral infarction and edema than selective brain cooling. The lack of protective effects of selective brain cooling may be caused by post-cooling cerebral hyperemia in the ischemia area.
-
Acta Neurochir. Suppl. · Jan 1998
Interhemispheric pressure gradients in severe head trauma in humans.
Interhemispheric pressure gradients may occur following severe head trauma in patients even in the absence of intracranial space occupying lesions. A higher ICP of the contralateral hemisphere may escape routine unilateral ICP monitoring. ⋯ According to our data with a limited number of patients, interhemispheric pressure gradients seem to occur in the initial posttraumatic phase in some patients, and they seem to resolve following adequate ICP treatment after several hours. Therefore, simultaneous bilateral ICP measurement may be warranted in the initial posttraumatic phase.
-
Acta Neurochir. Suppl. · Jan 1998
Increase in transcranial Doppler pulsatility index does not indicate the lower limit of cerebral autoregulation.
Transcranial Doppler pulsatility index was reported clinically to increase when cerebral perfusion pressure decreased, hypothetically marking the lower limit of cerebral autoregulation. We sought to investigate the relationship between pulsatility index, cerenbrovascular resistance, and cerebral perfusion pressure in various states of autoregulation in an animal model of moderate intracranial hypertension. ⋯ The increase in transcranial Doppler pulsatility index when cerebral perfusion pressure falls cannot be interpreted as a phenomenon able to mark the lower limit of cerebral autoregulation.