Anesthesia and analgesia
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Predicting flow through an IV cannula is useful to clinicians if changes in flow are required and to guide selection of cannula. We sought the usefulness of manufacturers' quoted flows in predicting actual flow and to characterize that flow. ⋯ Flow through cannulae is not laminar at the upper range of clinically used flows, therefore Poiseuille's law is not useful in predicting flow and the effect of changing radius is less than commonly believed. The quoted maximum flows are also not useful. There are many conditions for laminar flow apart from Reynolds number. Further work would determine useful predictors of flow.
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Anesthesia and analgesia · Apr 2009
ReviewA systematic review of randomized controlled trials that evaluate strategies to avoid epidural vein cannulation during obstetric epidural catheter placement.
In this systematic review, we evaluated the evidence for seven strategies which have been proposed to minimize the incidence of epidural vein cannulation during lumbar epidural catheter placement in pregnant women. ⋯ The risk of intravascular placement of a lumbar epidural catheter in pregnancy may be reduced with the lateral patient position, fluid predistension, a single orifice catheter, a wire-embedded polyurethane epidural catheter and limiting the depth of catheter insertion to 6 cm or less. In general, low manuscript quality weakens the strength of these conclusions.
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Anesthesia and analgesia · Apr 2009
Comparative StudyIntralipid infusion diminishes return of spontaneous circulation after hypoxic cardiac arrest in rabbits.
Infusion of lipid emulsion has been shown to reverse lipophilic drug-induced cardiovascular collapse in laboratory models and humans. The effect of high dose lipid in nondrug-induced cardiac arrest is, however, uncertain. In a rabbit model of asphyxial pulseless electrical activity (PEA) we compared lipid augmented with standard advanced cardiac life support (ACLS) resuscitation. ⋯ In this model of hypoxia-induced PEA, standard ACLS resulted in greater coronary perfusion pressure and increased ROSC compared with ACLS plus lipid infusion. Lipid emulsion may be contraindicated in cardiac arrest complicated by significant hypoxia.