Anesthesia and analgesia
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Anesthesia and analgesia · Sep 2009
ReviewIntraoperative awareness during general anesthesia for cesarean delivery.
Intraoperative awareness is defined as the spontaneous recall of an event occurring during general anesthesia. A move away from rigid anesthetic protocols, which were designed to limit drug transmission across the placenta, has reduced the incidence of awareness during cesarean delivery to approximately 0.26%. Nevertheless, it remains an undesirable complication with potential for the development of posttraumatic stress disorder. ⋯ Because of its rapid uptake, nitrous oxide remains an important adjunct to reduce the risk of awareness during emergency cesarean delivery. In the absence of fetal compromise, there is no rationale for an inspired oxygen concentration above 0.33. Deeper levels of anesthesia reduce the incidence of awareness; current evidence does not suggest an increased risk of tocolysis or fetal morbidity.
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Anesthesia and analgesia · Sep 2009
An anatomical study of the transversus abdominis plane block: location of the lumbar triangle of Petit and adjacent nerves.
The transversus abdominis plane (TAP) block is a new technique for providing analgesia to the anterior abdominal wall. Most previous studies have used the lumbar triangle of Petit as a landmark for the block. In this cadaveric study, we determined the exact position and size of the lumbar triangle of Petit and identified the nerves affected by the TAP block. ⋯ The lumbar triangles of Petit found in the specimens in this study were more posterior than the literature suggests. The position of the lumbar triangle of Petit varies largely and the size is relatively small. The relevant nerves to be blocked had not entered the TAP in the specimens in this study at the point of the lumbar triangle of Petit. At the midaxillary line, however, all the nerves were in the TAP.
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Anesthesia and analgesia · Sep 2009
Deep hypothermia attenuates microglial proliferation independent of neuronal death after prolonged cardiac arrest in rats.
Conventional resuscitation of exsanguination cardiac arrest (CA) victims is generally unsuccessful. Emergency preservation and resuscitation is a novel approach that uses an aortic flush to induce deep hypothermia during CA, followed by delayed resuscitation with cardiopulmonary bypass. Minocycline has been shown to be neuroprotective across a number of brain injury models via attenuating microglial activation. We hypothesized that deep hypothermia and minocycline would attenuate neuronal death and microglial activation and improve outcome after exsanguination CA in rats. ⋯ Deeper levels of hypothermia induced by the IC versus RT flush resulted in better neurological outcome in survivors. Surprisingly, deep hypothermia attenuated microglial activation but not hippocampal neuronal death. Minocycline had modest benefit on neurologic outcome in survivors but did not attenuate microglial activation in brain. Our findings suggest a novel effect of deep hypothermia on microglial proliferation during exsanguination CA.
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Anesthesia and analgesia · Sep 2009
Ketamine inhibits maturation of bone marrow-derived dendritic cells and priming of the Th1-type immune response.
Dendritic cells (DCs) play a key role as antigen-presenting cells and growing evidence suggests that DCs influence T-cell activation and regulate the polarity of the immune response. Ketamine has been reported to have immunomodulatory properties that affect immune cells, including macrophages and natural killer cells. However, the effect of ketamine on DCs has not been characterized. We examined the immunomodulation of DCs by ketamine. ⋯ Our findings suggest that ketamine inhibits the functional maturation of DCs and interferes with DC induction of Th1 immunity in the whole animal. These novel findings provide new insight into the immunopharmacological role of ketamine.
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Anesthesia and analgesia · Sep 2009
The effect of a peripheral block on inflammation-induced prostaglandin E2 and cyclooxygenase expression in rats.
Peripheral inflammatory pain is associated with an upregulation of spinal cord COX-2 (cyclooxygenase-2), with a subsequent increase in central prostaglandin E2 (PGE2) levels associated with the development of hyperalgesia. In this study, we evaluated the effect of bupivacaine administered via a nerve block or via a systemic route on the spinal expression of PGE2 and COX in a model of peripheral inflammation in rats. ⋯ These results constitute a key element strongly suggesting that local anesthetics act at a different level when administered systematically or via a nerve block.