We characterized the volume kinetics of crystalloid solutions (Ringer's lactate solution and 5% dextrose water) and colloid solutions (6% tetrastarch and 10% pentastarch) by nonlinear mixed-effects modeling in healthy volunteers. We also assessed whether the bioelectrical impedance analysis parameters are significant covariates for volume kinetic parameters. Twelve male volunteers were randomly allocated to four groups, and each group received the four fluid solutions in specified sequences, separated by 1-week intervals to avoid any carryover effects.
View Article and Find Full Text PDFBackground: In a previous study, the modified Marsh and Schnider models respectively showed negatively- and positively-biased predictions in underweight patients. To overcome this drawback, we developed a new pharmacokinetic propofol model-the Choi model-for use in underweight patients. In the present study, we evaluated the predictive performance of the Choi model.
View Article and Find Full Text PDFAlthough remifentanil is used widely by many clinicians during general anesthesia, there are recent evidences of opioid-induced hyperalgesia as an adverse effect. This study aimed to determine if intraoperative remifentanil infusion caused increased pain during the postoperative period in patients who underwent a thyroidectomy. A total of 7511 patients aged ≥ 20 years, who underwent thyroidectomy between January 2009 and December 2013 at the Asan Medical Center were retrospectively analyzed.
View Article and Find Full Text PDFConventional, intravenous, patient-controlled analgesia, which is only administered by demand bolus without basal continuous infusion, is closely associated with inappropriate analgesia. Pharmacokinetic model-based dosing schemes can quantitatively describe the time course of drug effects and achieve optimal drug therapy. We compared the efficacy and safety of a conventional dosing regimen for intravenous patient-controlled analgesia that was administered by demand bolus without basal continuous infusion (group A) versus a pharmacokinetic model-based dosing scheme performed by decreasing the dosage of basal continuous infusion according to the model-based simulation used to achieve a targeted concentration (group B) following robot-assisted laparoscopic prostatectomy.
View Article and Find Full Text PDFBackground: Although ultrasonography is recommended in internal jugular vein (IJV) catheterization, the landmark-guided technique should still be considered. The central landmark using the two heads of the sternocleidomastoid muscle is widely used, but it is inaccurate for IJV access. As an alternative landmark, we investigated the accuracy of the new landmark determined by inspection of the respiratory jugular venodilation and direct IJV palpation in right IJV access by ultrasonography.
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