Short communication Received: 25 February 2014,
Revised: 22 May 2014,
Accepted: 29 May 2014
Published online in Wiley Online Library
(wileyonlinelibrary.com) DOI 10.1002/bmc.3281
Simultaneous determination of propofol and remifentanil in rat plasma by liquid chromatography–tandem mass spectrometry: application to preclinical pharmacokinetic drug–drug interaction analysis Mohamed A. El Hamda, Mitsuhiro Wadaa, Rie Ikedaa, Shigeru Kawakamia, Naotaka Kurodaa and Kenichiro Nakashimab* ABSTRACT: Propofol (Pro) is an ultra-short-acting hypnotic agent used for general anesthesia that has no analgesic properties. Remifentanil (Rem) is an ultra-short-acting opioid administered concomitantly as an analgesic with Pro. To evaluate the pharmacokinetic interactions between Pro and Rem, we developed and validated a method combining high-performance liquid chromatography with tandem mass spectrometry for simultaneous determination of Pro and Rem. The proposed method was successfully used to study the pharmacokinetic interactions of Pro and Rem coadministered to rats. Copyright © 2014 John Wiley & Sons, Ltd. Additional supporting information may be found in the online version of this article at the publisher’s web site. Keywords: propofol; remifentanil; LC-MS/MS; rat plasma; pharmacokinetic interactions
Introduction
Material and methods
Owing to their desirable pharmacologic properties, such as rapid onset and short duration of action, propofol (Pro) and remifentanil (Rem) can be used simultaneously for general anesthesia (Miekisch et al., 2008; Kapila et al., 1995) (Suppl. Fig. 1). Total intravenous anesthesia (TIVA) with Pro and Rem is frequently used to induce and maintain general anesthesia because it obviates the need for inhalation of unsatisfactory anesthetic volatile liquids and has well-documented effect, tolerability, and safety profiles (Schmidt et al., 2005). However, overdosing patients with Pro or Rem in TIVA can cause cardiovascular depression (Kishimoto et al., 2011). Clinically, Rem decreases the concentration of Pro required for loss of consciousness (Lysakowski et al., 2001) owing to pharmacodynamic interaction between the compounds (Yufune et al., 2011). Therefore, pharmacokinetic interaction studies would clearly add to the knowledge base of specialists in the field of anesthesiology. Several methods for the determination of Pro and Rem individually have been reported, but no methods for the simultaneous determination of these compounds in routine clinical pharmacokinetic evaluations have been published (Suppl. file). In this study, we developed a liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) method for the simultaneous measurement of Pro (acidic analyte) and Rem (basic analyte) in rat plasma. Furthermore, the method was used to study the pharmacokinetic interaction of Pro and Rem after co-administration to rats via intravenous infusion.
Chemicals
Biomed. Chromatogr. 2014
Pro, sodium carbonate, sodium hydrogen carbonate, ammonium acetate, acetic acid and acetonitrile were obtained from Wako Pure Chemicals (Osaka, Japan). Rem hydrochloride was obtained from Janssen Pharmaceuticals Inc. (Tokyo, Japan). Carbamazepine (internal standard, IS; Suppl. Fig. 1) and tert-butyl methyl ether (t-BME) were obtained from Sigma-Aldrich Inc. (St Louis, MO, USA). All other reagents were of analytical reagent grade.
Pretreatment of plasma To 200 μL of rat plasma, 20 μL of IS (11.1 μg/mL of spiked solution in acetonitrile) was added and the sample was vortex-mixed, * Correspondence to: Kenichiro Nakashima, Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch Sasebo, Nagasaki 859-3298, Japan. Email: [email protected] a
Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyomachi, Nagasaki 852-8131, Japan
b
Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch Sasebo, Nagasaki 859-3298, Japan Abbreviations used: Pro, propofol; Rem, remifentanil; t-BME, tert-butyl methyl ether; TIVA, total intravenous anesthesia.
Copyright © 2014 John Wiley & Sons, Ltd.
M. A. El Hamd et al. after which 100 μL of acetonitrile was added for deproteinization. Next, 100 μL of sodium carbonate buffer (100 mM, pH 10) was added and the sample was vortex-mixed, after which 700 μL of t-BME was added for liquid–liquid extraction. After vortexmixing, the mixture was centrifuged (2000g) for 10 min at 4°C. The organic phase was then evaporated to dryness under nitrogen gas at room temperature. The resulting residue was dissolved in 50 μL of acetonitrile and analyzed by LC-MS/MS. LC-MS/MS system and conditions A Waters 2695 separation module (Waters Co., Milford, MA, USA) was used for the separation of analytes. Chromatographic separation was achieved using a Chromolith Performance RP-18e monolithic column (100 × 4.6 mm i.d.; Merck, Darmstadt, Germany) (Suppl. file), operated at a column temperature of 30°C and eluted with a mixture of acetonitrile–ammonium acetate buffer (10 mM, pH 3.5; 90:10, v/v) pumped at a flow rate of 0.5 mL/min as the mobile phase. A variable negative- and positive-ionization Quattro micro™ triple-quadrupole mass spectrometer (Waters) equipped with an electrospray ionization source was used for mass analysis. Mass spectrometric analysis was set up in the selected reaction monitoring mode; analyses were performed in negative-ion mode for Pro and positive-ion mode for Rem and the IS. Detailed mass spectrometry conditions were as follows: electrospray ionization capillary voltage (kV) was 3 for Pro and +3 for Rem and the IS; cone voltage (V) was 3, +15 and +20 for Pro, Rem and the IS, respectively; and the collision energy (eV) was 11, 14 and 17, for Pro, Rem and the IS, respectively. The following selected reaction monitoring transitions were optimized: m/z 176.94 [M H] → 160.87 (Pro), m/z 377.04 [M + H]+ → 317.04 (Rem) and m/z 237.07 [M + H]+ → 220.01 (IS) (Suppl. Fig. 2). Method validation Method validation was carried out according to US Food and Drug Administration (2001) guidelines and included validation of selectivity with respect to endogenous and exogenous substances, selectivity towards all analytes present in the assay sample, linearity, sensitivity, accuracy and precision. The matrix effect was calculated as the IS-normalized matrix factor, which was determined as the peak area ratio in the presence of matrix for each plasma sample divided by the mean of the peak area ratio in the absence of matrix.
differences between the area under the curve (AUC) for the two analysis periods was determined using Student’s t-test at a statistical significance level of p < 0.05.
Results and discussion Establishment of assay conditions The effects of ammonium acetate buffer (concentration and pH) and mobile phase acetonitrile content on analyte peak area were examined. Optimal separation of analytes was achieved using 10 mM ammonium acetate buffer at pH 3.5 with an acetonitrile content of 90% (v/v). To prevent ion suppression owing to the plasma matrix effect, all samples were deproteinized with acetonitrile (100 μL). The organic extractor for liquid–liquid extraction was determined to be t-BME, which provided low- and high-concentration extraction efficiencies of 86 ± 7% (0.5 μg/mL) and 95 ± 6% (10 μg/mL) for Pro, 79 ± 12% (1 ng/mL) and 86 ± 9% (50 ng/mL) for Rem, and 80 ± 5% for the IS. Method validation The proposed method was found to be selective, as potential interfering substances were controlled for by analyzing blank plasma samples obtained from 10 different rats (Suppl. Fig. 3). Pro and Rem analytical curves were linear in the ranges of 0.27–10 μg/mL (Pro) and 0.17–50 ng/mL (Rem), with correlation coefficients ≥0.976 (Suppl. file). The lower limits of detection for Pro and Rem were 0.16 μg/mL and 0.10 ng/mL, whereas the lower limit of quantitation was 0.27 μg/mL for Pro and 0.17 ng/mL for Rem. The sensitivity for Rem was sufficient for its determination in plasma samples, as the concentration ratio of Pro to Rem in clinical use is 1000:1. The calculated accuracy of Pro and Rem determination was between 19.4 ± 5.6 and 0.0 ± 5.4% (calculated as relative error ± standard deviation). Intra- and inter-day precisions of analysis were expressed in terms of percentage relative standard deviation of the peak area values (Table 1). The IS-normalized matrix factors at low and high concentrations in plasma were 1.08 ± 0.12 (0.5 μg/mL) and 1.11 ± 0.09 (10 μg/mL) for Pro and 1.14 ± 0.17 (1 ng/mL) and 1.15 ± 0.13 (50 ng/mL) for Rem. Thus, despite observance of a slight IS-normalized matrix factor, the present method was found to be reliable and reproducible for the determination of Pro and Rem in rat plasma.
Administration study Male Wistar rats (n = 6, weight 280–310 g) were used for the administration study. Pro in Intralipid® 10% emulsion (Fresenius Kabi, Tokyo; 125 μg/kg/min) and Rem in 0.9% saline (125 ng/kg/min) were administrated to the rats via intravenous infusion for 60 min using a CMA/100 microinjection pump (Carnegie Medicine, Stockholm, Sweden). After administration, blood samples (300 μL each) were collected at 10, 15, 25, 30–40, 45, 50, 55, 60 and 65 min (5 min after administration stopped). To avoid Rem degradation, 30 μL of 0.2 M citric acid was immediately added to each blood sample upon collection (Schmitt-Hoffmann et al., 2006). Two experiments were performed; the first experiment involved sole administration of Pro or Rem. The second experiment was divided into two parts; in the first part (0–30 min), Pro or Rem was administered independently, and in the second part (30–60 min), the drugs were coadministered. The significance of
wileyonlinelibrary.com/journal/bmc
Coadministration of Pro and Rem In sole-administration experiments, the plasma concentrations of Pro and Rem appeared to be constant (Fig. 1 A). The AUC15–30min and AUC45–60min were 7.19 ± 0.58 and 7.95 ± 1.08 μg/mL × min, respectively, for Pro and 4.42 ± 0.11 and 4.91 ± 0.19 ng/mL × min, respectively, for Rem. In concentration–time profiles of rats administered one drug independently for 30 min and then coadministered Pro and Rem from 30 to 60 min (Fig. 1B), a significant increase in the concentration of Rem was observed (p = 0.01), whereas the Pro concentration was stable (p = 0.44). The AUC15–30min and AUC45–60min were 8.40 ± 1.22 and 8.70 ± 1.42 μg/mL × min, respectively, for Pro and 5.49 ± 0.99 and 8.76 ± 0.94 ng/mL × min, respectively, for Rem. Rem did not alter the AUC of Pro, whereas Pro caused an increase in the concentration of Rem. These results are in
Copyright © 2014 John Wiley & Sons, Ltd.
Biomed. Chromatogr. 2014
Simultaneous determination of propofol and remifentanil in rat plasma Table 1. Accuracy and precision of the proposed method Drug
Spiked concentration (ng/mL)
Pro
Rem
Accuracy (%) (RE ± SD, n = 5)
500 2000 10000 1.0 10 50
19.4 ± 5.6 0.0 ± 5.4 7.0 ± 2.8 0.3 ± 5.1 1.9 ± 8.4 6.2 ± 2.1
Precision RSD (%) (n = 5) Intra-day
Inter-day
6.4 1.3 3.2 5.0 3.7 2.3
10.2 11.4 8.2 11.9 12.7 9.8
RE, relative error; RSD, relative standard deviation; Pro, propofol; Rem, remifentanil.
References
Figure 1. Plasma concentration–time profiles after sole administration of propofol (Pro) and remifentanil (Rem) (A) and sole and coadministration of Pro and/or Rem (B).
agreement with previously reported data (Martijin et al., 2001; Bouillon et al., 2002). Our data clearly indicate that Rem is affected by the presence of Pro when coadministered during general anesthesia. Our LC-MS/MS method, which enables the simultaneous determination of Pro and Rem, might be useful for rapidly identifying interactions between these drugs. However, further studies to elucidate the particular mechanism of action are necessary.
Biomed. Chromatogr. 2014
Bouillon T, Bruhn J, Radu-Radulescu L, Bertaccini E, Park S and Shafer S. Non-steady state analysis of the pharmacokinetic interaction between propofol and remifentanil. Anesthesiology 2002; 97: 1350–1362. Kapila A, Glass PS, Jacobs JR, Muir KT, Hermann DJ, Shiraishi M, Howell S and Smith RL. Measured context-sensitive half-times of remifentanil and alfentanil. Anesthesiology 1995; 83: 968–975. Kishimoto N, Koyama SH, Nagata N and Kotani J. Optimal concentration of sevoflurane to prevent cardiovascular depression after induction of general anesthesia with remifentanil and propofol. Journal of Anesthesia and Clinical Research 2011; 2: 1–7. Lysakowski C, Dumont L, Pellegrini M, Clergue F and Tassonyi E. Effects of fentanyl, alfentanil, remifentanil and sufentanil on loss of consciousness and bispectral index during propofol induction of anaesthesia. British Journal of Anaesthesia 2001; 86: 523–527. Martijn JM, Jaap V, Erik O, James GB and Anton GLB. Propofol alters the pharmacokinetics of alfentanil in healthy male volunteers. Anesthesiology 2001; 94: 949–957. Miekisch W, Fuchs P, Kamysek S, Neumann C and Schubert JK. Assessment of propofol concentrations in human breath and blood by means of HSSPME-GC-MS. Clinica Chimica Acta 2008; 395: 32–37. Schmidt J, Hering W and Albrecht S. Total intravenous anesthesia with propofol and remifentanil. Results of a multicenter study of 6,161 patients. Anaesthesist 2005; 54: 17–28. Schmitt-Hoffmann A, Roos B, Heep M, Schleimer M, Weidekamm E, Brown T, Roehrle M and Belinger C. Single-ascending-dose pharmacokinetics and safety of the novel broad-spectrum antifungal triazole BAL4815 after intravenous infusions (50, 100, and 200 milligrams) and oral administrations (100, 200, and 400 milligrams) of its prodrug, BAL8557, in healthy volunteers. Antimacrobial Agents and Chemotherapy 2006; 50: 279–285. US Food and Drug Administration. Guidance for Industry: Bioanalytical Method Validation. US Department of Health and Human Services, Food and Drug Administration, 2001. Available from: http://www.fda.gov/downloads/Drugs/Guidances/ucm070107.pdf (accessed 10 December 2013). Yufune S, Takamatsu I, Masui K and Kazama T. Effect of remifentanil on plasma propofol concentration and bispectral index during propofol anaesthesia. British Journal of Anaesthesia 2011; 106: 208–214.
Supporting information Additional supporting information may be found in the online version of this article at the publisher’s web site.
Copyright © 2014 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/bmc
Revised: 22 May 2014,
Accepted: 29 May 2014
Published online in Wiley Online Library
(wileyonlinelibrary.com) DOI 10.1002/bmc.3281
Simultaneous determination of propofol and remifentanil in rat plasma by liquid chromatography–tandem mass spectrometry: application to preclinical pharmacokinetic drug–drug interaction analysis Mohamed A. El Hamda, Mitsuhiro Wadaa, Rie Ikedaa, Shigeru Kawakamia, Naotaka Kurodaa and Kenichiro Nakashimab* ABSTRACT: Propofol (Pro) is an ultra-short-acting hypnotic agent used for general anesthesia that has no analgesic properties. Remifentanil (Rem) is an ultra-short-acting opioid administered concomitantly as an analgesic with Pro. To evaluate the pharmacokinetic interactions between Pro and Rem, we developed and validated a method combining high-performance liquid chromatography with tandem mass spectrometry for simultaneous determination of Pro and Rem. The proposed method was successfully used to study the pharmacokinetic interactions of Pro and Rem coadministered to rats. Copyright © 2014 John Wiley & Sons, Ltd. Additional supporting information may be found in the online version of this article at the publisher’s web site. Keywords: propofol; remifentanil; LC-MS/MS; rat plasma; pharmacokinetic interactions
Introduction
Material and methods
Owing to their desirable pharmacologic properties, such as rapid onset and short duration of action, propofol (Pro) and remifentanil (Rem) can be used simultaneously for general anesthesia (Miekisch et al., 2008; Kapila et al., 1995) (Suppl. Fig. 1). Total intravenous anesthesia (TIVA) with Pro and Rem is frequently used to induce and maintain general anesthesia because it obviates the need for inhalation of unsatisfactory anesthetic volatile liquids and has well-documented effect, tolerability, and safety profiles (Schmidt et al., 2005). However, overdosing patients with Pro or Rem in TIVA can cause cardiovascular depression (Kishimoto et al., 2011). Clinically, Rem decreases the concentration of Pro required for loss of consciousness (Lysakowski et al., 2001) owing to pharmacodynamic interaction between the compounds (Yufune et al., 2011). Therefore, pharmacokinetic interaction studies would clearly add to the knowledge base of specialists in the field of anesthesiology. Several methods for the determination of Pro and Rem individually have been reported, but no methods for the simultaneous determination of these compounds in routine clinical pharmacokinetic evaluations have been published (Suppl. file). In this study, we developed a liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) method for the simultaneous measurement of Pro (acidic analyte) and Rem (basic analyte) in rat plasma. Furthermore, the method was used to study the pharmacokinetic interaction of Pro and Rem after co-administration to rats via intravenous infusion.
Chemicals
Biomed. Chromatogr. 2014
Pro, sodium carbonate, sodium hydrogen carbonate, ammonium acetate, acetic acid and acetonitrile were obtained from Wako Pure Chemicals (Osaka, Japan). Rem hydrochloride was obtained from Janssen Pharmaceuticals Inc. (Tokyo, Japan). Carbamazepine (internal standard, IS; Suppl. Fig. 1) and tert-butyl methyl ether (t-BME) were obtained from Sigma-Aldrich Inc. (St Louis, MO, USA). All other reagents were of analytical reagent grade.
Pretreatment of plasma To 200 μL of rat plasma, 20 μL of IS (11.1 μg/mL of spiked solution in acetonitrile) was added and the sample was vortex-mixed, * Correspondence to: Kenichiro Nakashima, Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch Sasebo, Nagasaki 859-3298, Japan. Email: [email protected] a
Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyomachi, Nagasaki 852-8131, Japan
b
Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch Sasebo, Nagasaki 859-3298, Japan Abbreviations used: Pro, propofol; Rem, remifentanil; t-BME, tert-butyl methyl ether; TIVA, total intravenous anesthesia.
Copyright © 2014 John Wiley & Sons, Ltd.
M. A. El Hamd et al. after which 100 μL of acetonitrile was added for deproteinization. Next, 100 μL of sodium carbonate buffer (100 mM, pH 10) was added and the sample was vortex-mixed, after which 700 μL of t-BME was added for liquid–liquid extraction. After vortexmixing, the mixture was centrifuged (2000g) for 10 min at 4°C. The organic phase was then evaporated to dryness under nitrogen gas at room temperature. The resulting residue was dissolved in 50 μL of acetonitrile and analyzed by LC-MS/MS. LC-MS/MS system and conditions A Waters 2695 separation module (Waters Co., Milford, MA, USA) was used for the separation of analytes. Chromatographic separation was achieved using a Chromolith Performance RP-18e monolithic column (100 × 4.6 mm i.d.; Merck, Darmstadt, Germany) (Suppl. file), operated at a column temperature of 30°C and eluted with a mixture of acetonitrile–ammonium acetate buffer (10 mM, pH 3.5; 90:10, v/v) pumped at a flow rate of 0.5 mL/min as the mobile phase. A variable negative- and positive-ionization Quattro micro™ triple-quadrupole mass spectrometer (Waters) equipped with an electrospray ionization source was used for mass analysis. Mass spectrometric analysis was set up in the selected reaction monitoring mode; analyses were performed in negative-ion mode for Pro and positive-ion mode for Rem and the IS. Detailed mass spectrometry conditions were as follows: electrospray ionization capillary voltage (kV) was 3 for Pro and +3 for Rem and the IS; cone voltage (V) was 3, +15 and +20 for Pro, Rem and the IS, respectively; and the collision energy (eV) was 11, 14 and 17, for Pro, Rem and the IS, respectively. The following selected reaction monitoring transitions were optimized: m/z 176.94 [M H] → 160.87 (Pro), m/z 377.04 [M + H]+ → 317.04 (Rem) and m/z 237.07 [M + H]+ → 220.01 (IS) (Suppl. Fig. 2). Method validation Method validation was carried out according to US Food and Drug Administration (2001) guidelines and included validation of selectivity with respect to endogenous and exogenous substances, selectivity towards all analytes present in the assay sample, linearity, sensitivity, accuracy and precision. The matrix effect was calculated as the IS-normalized matrix factor, which was determined as the peak area ratio in the presence of matrix for each plasma sample divided by the mean of the peak area ratio in the absence of matrix.
differences between the area under the curve (AUC) for the two analysis periods was determined using Student’s t-test at a statistical significance level of p < 0.05.
Results and discussion Establishment of assay conditions The effects of ammonium acetate buffer (concentration and pH) and mobile phase acetonitrile content on analyte peak area were examined. Optimal separation of analytes was achieved using 10 mM ammonium acetate buffer at pH 3.5 with an acetonitrile content of 90% (v/v). To prevent ion suppression owing to the plasma matrix effect, all samples were deproteinized with acetonitrile (100 μL). The organic extractor for liquid–liquid extraction was determined to be t-BME, which provided low- and high-concentration extraction efficiencies of 86 ± 7% (0.5 μg/mL) and 95 ± 6% (10 μg/mL) for Pro, 79 ± 12% (1 ng/mL) and 86 ± 9% (50 ng/mL) for Rem, and 80 ± 5% for the IS. Method validation The proposed method was found to be selective, as potential interfering substances were controlled for by analyzing blank plasma samples obtained from 10 different rats (Suppl. Fig. 3). Pro and Rem analytical curves were linear in the ranges of 0.27–10 μg/mL (Pro) and 0.17–50 ng/mL (Rem), with correlation coefficients ≥0.976 (Suppl. file). The lower limits of detection for Pro and Rem were 0.16 μg/mL and 0.10 ng/mL, whereas the lower limit of quantitation was 0.27 μg/mL for Pro and 0.17 ng/mL for Rem. The sensitivity for Rem was sufficient for its determination in plasma samples, as the concentration ratio of Pro to Rem in clinical use is 1000:1. The calculated accuracy of Pro and Rem determination was between 19.4 ± 5.6 and 0.0 ± 5.4% (calculated as relative error ± standard deviation). Intra- and inter-day precisions of analysis were expressed in terms of percentage relative standard deviation of the peak area values (Table 1). The IS-normalized matrix factors at low and high concentrations in plasma were 1.08 ± 0.12 (0.5 μg/mL) and 1.11 ± 0.09 (10 μg/mL) for Pro and 1.14 ± 0.17 (1 ng/mL) and 1.15 ± 0.13 (50 ng/mL) for Rem. Thus, despite observance of a slight IS-normalized matrix factor, the present method was found to be reliable and reproducible for the determination of Pro and Rem in rat plasma.
Administration study Male Wistar rats (n = 6, weight 280–310 g) were used for the administration study. Pro in Intralipid® 10% emulsion (Fresenius Kabi, Tokyo; 125 μg/kg/min) and Rem in 0.9% saline (125 ng/kg/min) were administrated to the rats via intravenous infusion for 60 min using a CMA/100 microinjection pump (Carnegie Medicine, Stockholm, Sweden). After administration, blood samples (300 μL each) were collected at 10, 15, 25, 30–40, 45, 50, 55, 60 and 65 min (5 min after administration stopped). To avoid Rem degradation, 30 μL of 0.2 M citric acid was immediately added to each blood sample upon collection (Schmitt-Hoffmann et al., 2006). Two experiments were performed; the first experiment involved sole administration of Pro or Rem. The second experiment was divided into two parts; in the first part (0–30 min), Pro or Rem was administered independently, and in the second part (30–60 min), the drugs were coadministered. The significance of
wileyonlinelibrary.com/journal/bmc
Coadministration of Pro and Rem In sole-administration experiments, the plasma concentrations of Pro and Rem appeared to be constant (Fig. 1 A). The AUC15–30min and AUC45–60min were 7.19 ± 0.58 and 7.95 ± 1.08 μg/mL × min, respectively, for Pro and 4.42 ± 0.11 and 4.91 ± 0.19 ng/mL × min, respectively, for Rem. In concentration–time profiles of rats administered one drug independently for 30 min and then coadministered Pro and Rem from 30 to 60 min (Fig. 1B), a significant increase in the concentration of Rem was observed (p = 0.01), whereas the Pro concentration was stable (p = 0.44). The AUC15–30min and AUC45–60min were 8.40 ± 1.22 and 8.70 ± 1.42 μg/mL × min, respectively, for Pro and 5.49 ± 0.99 and 8.76 ± 0.94 ng/mL × min, respectively, for Rem. Rem did not alter the AUC of Pro, whereas Pro caused an increase in the concentration of Rem. These results are in
Copyright © 2014 John Wiley & Sons, Ltd.
Biomed. Chromatogr. 2014
Simultaneous determination of propofol and remifentanil in rat plasma Table 1. Accuracy and precision of the proposed method Drug
Spiked concentration (ng/mL)
Pro
Rem
Accuracy (%) (RE ± SD, n = 5)
500 2000 10000 1.0 10 50
19.4 ± 5.6 0.0 ± 5.4 7.0 ± 2.8 0.3 ± 5.1 1.9 ± 8.4 6.2 ± 2.1
Precision RSD (%) (n = 5) Intra-day
Inter-day
6.4 1.3 3.2 5.0 3.7 2.3
10.2 11.4 8.2 11.9 12.7 9.8
RE, relative error; RSD, relative standard deviation; Pro, propofol; Rem, remifentanil.
References
Figure 1. Plasma concentration–time profiles after sole administration of propofol (Pro) and remifentanil (Rem) (A) and sole and coadministration of Pro and/or Rem (B).
agreement with previously reported data (Martijin et al., 2001; Bouillon et al., 2002). Our data clearly indicate that Rem is affected by the presence of Pro when coadministered during general anesthesia. Our LC-MS/MS method, which enables the simultaneous determination of Pro and Rem, might be useful for rapidly identifying interactions between these drugs. However, further studies to elucidate the particular mechanism of action are necessary.
Biomed. Chromatogr. 2014
Bouillon T, Bruhn J, Radu-Radulescu L, Bertaccini E, Park S and Shafer S. Non-steady state analysis of the pharmacokinetic interaction between propofol and remifentanil. Anesthesiology 2002; 97: 1350–1362. Kapila A, Glass PS, Jacobs JR, Muir KT, Hermann DJ, Shiraishi M, Howell S and Smith RL. Measured context-sensitive half-times of remifentanil and alfentanil. Anesthesiology 1995; 83: 968–975. Kishimoto N, Koyama SH, Nagata N and Kotani J. Optimal concentration of sevoflurane to prevent cardiovascular depression after induction of general anesthesia with remifentanil and propofol. Journal of Anesthesia and Clinical Research 2011; 2: 1–7. Lysakowski C, Dumont L, Pellegrini M, Clergue F and Tassonyi E. Effects of fentanyl, alfentanil, remifentanil and sufentanil on loss of consciousness and bispectral index during propofol induction of anaesthesia. British Journal of Anaesthesia 2001; 86: 523–527. Martijn JM, Jaap V, Erik O, James GB and Anton GLB. Propofol alters the pharmacokinetics of alfentanil in healthy male volunteers. Anesthesiology 2001; 94: 949–957. Miekisch W, Fuchs P, Kamysek S, Neumann C and Schubert JK. Assessment of propofol concentrations in human breath and blood by means of HSSPME-GC-MS. Clinica Chimica Acta 2008; 395: 32–37. Schmidt J, Hering W and Albrecht S. Total intravenous anesthesia with propofol and remifentanil. Results of a multicenter study of 6,161 patients. Anaesthesist 2005; 54: 17–28. Schmitt-Hoffmann A, Roos B, Heep M, Schleimer M, Weidekamm E, Brown T, Roehrle M and Belinger C. Single-ascending-dose pharmacokinetics and safety of the novel broad-spectrum antifungal triazole BAL4815 after intravenous infusions (50, 100, and 200 milligrams) and oral administrations (100, 200, and 400 milligrams) of its prodrug, BAL8557, in healthy volunteers. Antimacrobial Agents and Chemotherapy 2006; 50: 279–285. US Food and Drug Administration. Guidance for Industry: Bioanalytical Method Validation. US Department of Health and Human Services, Food and Drug Administration, 2001. Available from: http://www.fda.gov/downloads/Drugs/Guidances/ucm070107.pdf (accessed 10 December 2013). Yufune S, Takamatsu I, Masui K and Kazama T. Effect of remifentanil on plasma propofol concentration and bispectral index during propofol anaesthesia. British Journal of Anaesthesia 2011; 106: 208–214.
Supporting information Additional supporting information may be found in the online version of this article at the publisher’s web site.
Copyright © 2014 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/bmc
