Anesthesia and analgesia
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Anesthesia and analgesia · Jul 2009
Comparative StudyA comparison of the effects on respiratory carbon dioxide response, arterial blood pressure, and heart rate of dexmedetomidine, propofol, and midazolam in sevoflurane-anesthetized rabbits.
Dexmedetomidine, propofol, and midazolam are commonly used sedative-hypnotic drugs. Using a steady-state method, we examined the CO2 ventilatory response, mean arterial blood pressure (MAP) and heart rate (HR) effects of these three drugs in sevoflurane-anesthetized rabbits. ⋯ The major finding is that, during sevoflurane anesthesia in rabbits, dexmedetomidine slightly altered the ventilatory response to CO2. It decreased MAP more than propofol and midazolam, which both significantly depressed the ventilatory response to CO2.
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Anesthesia and analgesia · Jul 2009
Comparative StudyOxygen and glucose deprivation in an organotypic hippocampal slice model of the developing rat brain: the effects on N-methyl-D-aspartate subunit composition.
Organotypic hippocampal slices (OHS) are commonly used to screen for neuroprotective effects of pharmacological agents relevant to pediatric brain injury. The importance of donor rat pup age and N-methyl-D-aspartate (NMDA) receptor subunit composition have not been addressed. In this study, we evaluated the age-dependent effect of oxygen-glucose deprivation (OGD) in the developing rat brain and determined whether OGD modulates the NMDA receptor subunit composition. ⋯ This in vitro neonatal rat pup investigation using OHS supports both an age and an NMDA receptor subunit composition-dependent relationship between OGD and neuronal cell death.
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Anesthesia and analgesia · Jul 2009
Comparative StudyThe shivering threshold in rabbits with JM-1232(-), a new benzodiazepine receptor agonist.
JM-1232(-) is a novel isoindoline derivative which shows sedative and hypnotic activities through the benzodiazepine site of gamma-aminobutyric acid type A (GABAA) receptors. Typical doses of midazolam, another GABAA receptor agonist, slightly reduce the shivering threshold in humans. We thus determined the extent to which JM-1232(-) decreases the shivering threshold. ⋯ A low dose of JM-1232(-) reduced the shivering threshold in rabbits approximately 0.8 degrees C which is similar to the effects in humans given premedication doses of midazolam. In contrast, a 10-fold larger dose reduced the threshold more than 2.5 degrees C. This is a substantial decrement and might facilitate induction of therapeutic hypothermia.
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Anesthesia and analgesia · Jul 2009
Comparative StudyPredicted propofol effect-site concentration for induction and emergence of anesthesia during early pregnancy.
Pregnancy is associated with decreased hypnotic requirement, allegedly related to progesterone. However, the effects of pregnancy and progesterone on propofol requirement have not been thoroughly investigated. We conducted this study to determine whether propofol dose and predicted effect-site concentration for loss of consciousness (LOC) during induction of anesthesia, and eye opening during emergence from anesthesia, are decreased during early pregnancy. We also investigated whether blood progesterone was correlated with propofol dose and effect-site concentration for LOC. ⋯ Propofol dose and predicted propofol effect-site concentration at LOC are decreased during early pregnancy. Progesterone does not explain this result.
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Anesthesia and analgesia · Jul 2009
Case ReportsHelmet ventilation for acute respiratory failure and nasal skin breakdown in neuromuscular disorders.
Noninvasive ventilation (NIV) has been widely used to decrease the complications associated with tracheal intubation in mechanically ventilated patients with neuromuscular diseases in acute respiratory failure. However, nasal ulcerations might occur when masks are used as an interface. ⋯ Helmet pressure support ventilation caused significant patient-ventilator asynchrony, leading to NIV intolerance. Thus, biphasic positive airway pressure delivered by helmet was applied, which improved gas exchange and patient-ventilator interaction, allowing successful NIV.