Skip to main content
Log in

Context-Sensitive Half-Times

What Are They and How Valuable Are They in Anaesthesiology?

  • Leading Article
  • Published:
Clinical Pharmacokinetics Aims and scope Submit manuscript

Abstract

The context-sensitive half-time is the time required for blood or plasma concentrations of a drug to decrease by 50% after discontinuation of drug administration. The context-sensitive half-time often cannot be predicted by the elimination half-life (a measure of the time needed for actual drug metabolism or elimination) since it also depends on drug distribution. The context-sensitive half-time is a function of the duration of drug administration and may only be estimated by computer simulation. It is more relevant than other isolated pharmacokinetic parameters to understanding the kinetics of drug concentrations. However, understanding the kinetics of drug effect requires concomitant consideration of pharmacodynamics.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3

Similar content being viewed by others

References

  1. Price HL. A dynamic concept of the distribution of thiopental in the human body. Anesthesiology 1960; 21: 40–5

    Article  PubMed  CAS  Google Scholar 

  2. Shafer SL, Varvel JR. Pharmacokinetics, pharmacodynamics, and rational opioid selection. Anesthesiology 1991; 74:53–63

    Article  PubMed  CAS  Google Scholar 

  3. Hughes MA, Glass PSA, Jacobs JR. Context-sensitive half-time in multicompartment pharmacokinetic models for intravenous anesthetic drugs. Anesthesiology 1992; 76: 334–41

    Article  PubMed  CAS  Google Scholar 

  4. Shafer SL, Stanski DR. Improving the clinical utility of anesthetic drug pharmacokinetics. Anesthesiology 1992; 76: 327–30

    Article  PubMed  CAS  Google Scholar 

  5. Youngs EJ, Shafer SL. Pharmacokinetic parameters relevant to recovery from opioids. Anesthesiology 1994; 81: 833–42

    Article  PubMed  CAS  Google Scholar 

  6. Kapila A, Glass PS, Jacobs JR, et al. Measured context-sensitive half-times of remifentanil and alfentanil. Anesthesiology 1995; 83: 968–75

    Article  PubMed  CAS  Google Scholar 

  7. Egan TD, Minto CF, Hermann DJ, et al. Remifentanil versus alfentanil: comparative pharmacokinetics and pharmacodynamics in healthy adult male volunteers. Anesthesiology 1995; 84: 821–33

    Article  Google Scholar 

  8. Bouillon T, Kietzmann D, Port R, et al. Population pharmacokinetics of piritramide in surgical patients. Anesthesiology 1999; 90: 7–15

    Article  PubMed  CAS  Google Scholar 

  9. Schickendantz J, Funk W, Ittner KP, et al. Elimination of methohexitone after long-term high-dose infusion in patients with critically elevated intracranial pressure. Critical Care Medicine 1999; 27: 1570–6

    Article  PubMed  CAS  Google Scholar 

  10. Ericsson H, Bredberg U, Eriksson U, et al. Pharmacokinetics and arteriovenous differences in clevidipine concentration following a short- and a long-term intravenous infusion in healthy volunteers. Anesthesiology 2000; 92: 993–1001

    Article  PubMed  CAS  Google Scholar 

  11. Bailey JM. Context-sensitive half-times and other decrement times of inhaled anesthetics. Anesth Analg 1997; 85: 681–6

    PubMed  CAS  Google Scholar 

  12. Bailey JM, Mora CT, Shafer SL. The pharmacokinetics of propofol in adult patients undergoing coronary revascularization. Anesthesiology 1996; 84: 1288–97

    Article  PubMed  CAS  Google Scholar 

  13. Vuyk J, Lim T, Engbers FHM, et al. The pharmacodynamic interaction of propofol and alfentanil during lower abdominal surgery in women. Anesthesiology 1995; 83: 8–22

    Article  PubMed  CAS  Google Scholar 

  14. Vuyk J, Engbers FHM, Lemmens HJM, et al. Pharmacodynamics of propofol in female patients. Anesthesiology 1992; 77: 3–9

    Article  PubMed  CAS  Google Scholar 

  15. Dwyer R, Bennett HL, Eger EI, et al. Effects of isoflurane and nitrous oxide in subanesthetic concentrations on memory and responsiveness in volunteers. Anesthesiology 1992; 77: 888–98

    Article  PubMed  CAS  Google Scholar 

  16. Glass PS, Bloom M, Kearse L, et al. Bispectral analysis measures sedation and memory effects of propofol, midazolam, isoflurane, and alfentanil in healthy volunteers. Anesthesiology 1997; 86: 836–47

    Article  PubMed  CAS  Google Scholar 

  17. Chortkoff BS, Eger EI, Crankshaw DP, et al. Concentrations of desflurane and propofol that suppress response to command in humans. Anesth Analg 1995; 81: 737–43

    PubMed  CAS  Google Scholar 

  18. McEwan AI, Smith C, Dyar O, et al. Isoflurane minimum alveolar concentration reduction by fentanyl. Anesthesiology 1993; 78: 864–9

    Article  PubMed  CAS  Google Scholar 

  19. Schraag S, Mohl U, Hirsch M, et al. Recovery from opioid anesthesia: the clinical implication of context-sensitive half-times. Anesth Analg 1998; 86: 184–90

    PubMed  CAS  Google Scholar 

  20. Bailey JM. A technique for quantifying the duration of intravenous anesthetic effect. Anesthesiology 1995; 83: 1095–103

    Article  PubMed  CAS  Google Scholar 

Download references

Acknowledgements

No sources of funding were used to assist in the preparation of this manuscript. The author has no conflicts of interest that are directly relevant to the content of this manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to James M. Bailey.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bailey, J.M. Context-Sensitive Half-Times. Clin Pharmacokinet 41, 793–799 (2002). https://doi.org/10.2165/00003088-200241110-00001

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.2165/00003088-200241110-00001

Keywords

Navigation