Anesthesia and analgesia
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Anesthesia and analgesia · Apr 2012
Multicenter StudyIncreases in electroencephalogram and electromyogram variability are associated with an increased incidence of intraoperative somatic response.
sBIS, the variability of the Bispectral Index (BIS), sEMG, the variability of facial electromyogram power (EMG), and the Composite Variability Index (CVI) are 3 new measures of electroencephalogram and EMG variability. CVI is a single measure of the combined variability in BIS and EMG. We investigated whether increases in these variables are associated with intraoperative somatic responses. ⋯ sBIS, sEMG, and CVI, measures of electroencephalogram and EMG variability, increased when intraoperative somatic events occurred. sBIS, sEMG, and CVI discriminated between 10-minute segments that contained a somatic event and those segments that did not contain an event better than changes in HR and mean arterial blood pressure. Furthermore, CVI increases before somatic events began earlier than HR changes and may provide caregivers with an early warning of potentially inadequate antinociception.
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Anesthesia and analgesia · Apr 2012
Noninvasive autoregulation monitoring in a swine model of pediatric cardiac arrest.
Cerebrovascular autoregulation after resuscitation has not been well studied in an experimental model of pediatric cardiac arrest. Furthermore, developing noninvasive methods of monitoring autoregulation using near-infrared spectroscopy (NIRS) would be clinically useful in guiding neuroprotective hemodynamic management after pediatric cardiac arrest. We tested the hypotheses that the lower limit of autoregulation (LLA) would shift to a higher arterial blood pressure between 1 and 2 days of recovery after cardiac arrest and that the LLA would be detected by NIRS-derived indices of autoregulation in a swine model of pediatric cardiac arrest. We also tested the hypothesis that autoregulation with hypertension would be impaired after cardiac arrest. ⋯ In a swine model of pediatric hypoxic-asphyxic cardiac arrest with confirmed brain damage, the LLA did not differ 1 and 2 days after resuscitation. The NIRS-derived indices accurately detected the LLA in comparison with laser-Doppler flow measurements at those time points. Autoregulation remained functional during hypertension.
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Anesthesia and analgesia · Apr 2012
Case ReportsThe effect of lipid emulsion infusion on postmortem ropivacaine concentrations in swine: endeavoring to comprehend a soldier's death.
Lipid emulsion (20%) is advocated as a rescue drug for local anesthetic toxicity. No study has measured the impact of lipid emulsion therapy on postmortem local anesthetic serum levels. ⋯ Our data show that postmortem blood samples in swine that experience local anesthetic cardiovascular collapse and are treated with lipid emulsions will result in measurements that cannot be directly extrapolated to premortem drug concentrations.