Anesthesiology
-
Randomized Controlled Trial Comparative Study Clinical Trial
Paravertebral analgesia with levobupivacaine increases postoperative flap tissue oxygen tension after immediate latissimus dorsi breast reconstruction compared with intravenous opioid analgesia.
Directly measured tissue oxygen tension (Pto2) reflects the adequacy of local tissue oxygenation and influences surgical wound healing. Epidural analgesia increases Pto2 compared with intravenous morphine analgesia after abdominal surgery. The authors tested the hypothesis that paravertebral regional anesthesia and analgesia would increase Pto2 compared with intravenous opioid-based anesthesia and analgesia. ⋯ The postoperative latissimus dorsi flap Pto2 was higher for 20 h after breast reconstruction with paravertebral analgesia compared with intravenous morphine analgesia.
-
Randomized Controlled Trial Clinical Trial
Antichemical protective gear prolongs time to successful airway management: a randomized, crossover study in humans.
Airway management is the first step in resuscitation. The extraordinary conditions in mass casualty situations impose special difficulties in airway management, even for experienced caregivers. The authors evaluated whether wearing surgical attire or antichemical protective gear made any difference in anesthetists' success of airway control with either an endotracheal tube or a laryngeal mask airway. ⋯ This first report in humans shows to what extent anesthetists' wearing of antichemical protective gear slows the time to intubate but not to insert a laryngeal mask airway compared with wearing surgical attire. Laryngeal mask airway insertion is faster than tracheal intubation when wearing protective gear, indicating its advantage for airway management when anesthetists wear antichemical protective gear. If chances for rapid and successful tracheal intubation under such chaotic conditions are poor, laryngeal mask airway insertion is a viable choice for airway management until a proper secured airway is obtainable.
-
Randomized Controlled Trial Clinical Trial
An investigation to dissociate the analgesic and anesthetic properties of ketamine using functional magnetic resonance imaging.
Anatomic sites within the brain, which activate in response to noxious stimuli, can be identified with the use of functional magnetic resonance imaging. The aim of this study was to determine whether the analgesic effects of ketamine could be imaged. ⋯ The analgesic effect can be measured within a more global effect of ketamine as shown by auditory and motor tasks, and the analgesia produced by ketamine occurs with a smaller degree of cortical processing in pain-related regions.
-
Clinical Trial
Mixed-effects modeling of the intrinsic ventilatory depressant potency of propofol in the non-steady state.
Despite the ubiquitous use of propofol for anesthesia and conscious sedation and numerous publications about its effect, a pharmacodynamic model for propofol-induced ventilatory depression in the non-steady state has not been described. To investigate propofol-induced ventilatory depression in the clinically important range (at and below the metabolic hyperbola while carbon dioxide is accumulating because of drug-induced ventilatory depression), the authors applied indirect effect modeling to Paco2 data at a fraction of inspired carbon dioxide of 0 during and after administration of propofol. ⋯ Propofol at common clinical concentrations is a potent ventilatory depressant. An indirect response model accurately described the magnitude and time course of propofol-induced ventilatory depression. The indirect response model can be used to optimize propofol administration to reduce the risk of significant ventilatory depression.
-
Anatomic and physiologic data show that multiple regions of the forebrain are activated by pain. However, the effect of anesthetic level on nociceptive input to these regions is not well understood. ⋯ These data show that propofol has a dose-dependent effect on thalamocortical transfer of nociceptive information but that some pain-evoked cortical activity remains after loss of consciousness.