Anesthesia and analgesia
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Anesthesia and analgesia · Feb 2012
Comparative StudyThe impact on drug mass flow rate of interrupting and resuming carrier fluid flow: an in vitro study on a very low dead-space volume infusion set.
Stopping and resuming carrier fluid flow can lead to potentially dangerous transient disturbances in drug mass flow rate. We compared the impact of 2 infusion sets, one with very low dead-space volume and the other with greater dead-space volume, on the amount of drug delivered during stop-and-go carrier fluid flows. ⋯ The use of a very low dead-space volume set attenuates disturbances in drug delivery caused by interrupting and resuming carrier fluid flow.
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Anesthesia and analgesia · Feb 2012
Intravenous fluids cause systemic bias in a conductivity-based point-of-care hematocrit meter.
Point-of-care (POC) devices measuring hematocrit rely on determination of electrical conductivity of whole blood. We hypothesized that some frequently administered IV fluids independently alter blood conductivity and confound hematocrit determination. ⋯ Dilution of blood with frequently used IV solutions affects whole blood conductivity determinations and thereby decreases hematocrits measured by a POC device relying on this method as compared with spun hematocrit. Conductivity-based hematocrit POC devices should be cautiously interpreted when hemodilution is present.
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Anesthesia and analgesia · Feb 2012
Comparative StudyR(+)-, Rac-, and S(-)-bupivacaine stereostructure-specifically interact with membrane lipids at cardiotoxically relevant concentrations.
It remains questionable whether local anesthetics can interact with membrane lipids at clinically relevant concentrations to show the difference between enantiomers. We compared the effects of bupivacaine stereoisomers on biomimetic membranes containing cardiolipin and cholesterol. ⋯ Such differences became greater with decreasing drug concentrations, possibly explaining the inconsistent cardiotoxic potencies of bupivacaine stereoisomers reported previously. The interactivity with biomembranes may in part contribute to the mode of toxic action of local anesthetics.
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Anesthesia and analgesia · Feb 2012
Editorial Historical ArticleRegional analgesia for postoperative pain: then & now.