Acta neurochirurgica. Supplement
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Acta Neurochir. Suppl. · Jan 1998
Effects on intracranial pressure of fentanyl in severe head injured patients.
Despite opioids are routinely used for analgesia in head injured patients, the effects of such drugs on ICP and cerebral hemodynamics remain controversial. Cerebrovascular autoregulation (CAR) could be an important factor in the ICP increases reported after opioid administration. In order to describe the effects on intracranial pressure of fentanyl and correlated such effects with autoregulation status, we studied 30 consecutive severe head injury patients who received fentanyl (2 micrograms/kg) intravenously over one minute. ⋯ In patients with preserved CAR (34.5%), opioid-induced ICP increase was greater (but not statistically significant) than in those with impaired CAR (65.5%). We conclude than fentanyl moderately increased ICP and decreased MAP and CPP. Our data suggests that in patients with preserved CAR, potent opioids could cause greater increases of ICP, probably due to activation of the vasodilatadory cascade.
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Acta Neurochir. Suppl. · Jan 1998
Comparative StudyCerebral oxygenation in contusioned vs. nonlesioned brain tissue: monitoring of PtiO2 with Licox and Paratrend.
Brain tissue PO2 in severely head injured patients was monitored in parallel with two different PO2-microsensors (Licox and Paratrend). Three different locations of sensor placement were chosen: (1) both catheters into non lesioned tissue (n = 3), (2) both catheters into contusioned tissue (n = 2), and (3) one catheter (Licox) into pericontusional versus one catheter (Paratrend) into non lesioned brain tissue (n = 2). Mean duration of PtiO2-monitoring with both microsensors in parallel was 68.1 hours. ⋯ During a critical reduction in cerebral perfusion pressure (< 60 mm Hg), PtiO2 decreased measured with both microsensors. Elevation of inspired oxygen fraction, normally followed by a rapid increase in tissue PO2, only increased PtiO2 when measured in pericontusional and nonlesioned brain. To recognize critical episodes of hypoxia or ischemia, PtiO2-monitoring of cerebral oxygenation is recommended in nonlesioned brain tissue.
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Acta Neurochir. Suppl. · Jan 1998
External lumbar drainage in uncontrollable intracranial pressure in adults with severe head injury: a report of 7 cases.
The retrospective results of external lumbar drainage in 7 adult patients with severe closed head injury and intracranial pressure (ICP) refractory to aggressive management strategies are presented. All patients had Glasgow Coma Scale (GCS) scores of 8 or less within 24 hours after admission and were treated by a staircase protocol including sedation, ventricular drainage, hyperventilation and mannitol. In three cases barbiturate drugs and an artificially induced hypothermia were used. ⋯ Three patients made a good functional recovery, 2 were severely disabled and 2 patients died. In none of the patients clinical signs of cerebral herniation occurred. We recommend additional external lumbar drainage in adults with severe head injury unresponsive to aggressive ICP control with open basilar cisterns and absent focal mass lesions on computerized-tomography scan before drainage.
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Acta Neurochir. Suppl. · Jan 1998
Continuous monitoring of cerebrovascular pressure-reactivity in head injury.
Cerebrovascular vasomotor reactivity reflects changes in smooth muscle tone in the arterial wall in response to changes in transmural pressure or concentration of carbon dioxide in blood. We have investigated whether slow waves in ABP and ICP may be used to derive an index which reflects reactivity of vessels to changes in arterial blood pressure. ⋯ Computer analysis of slow waves in ABP and ICP is able to provide a continuous index of cerebrovascular reactivity to changes in arterial pressure, which is of prognostic significance.
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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.