ISSN:
1432-1041
Keywords:
morphine
;
anesthesiology
;
epidural application
;
pharmacokinetics
;
plasma level
;
CSF level
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Medicine
Notes:
Summary Cerebrospinal fluid (CSF) and plasma morphine concentrations were determined in 5 patients after epidural administration of 6 mg morphine; plasma samples were collected frequently during the initial 6 h and 6–7 CSF samples were obtained from each patient over a 24 h period. Morphine was analysed using gas chromatography and electron capture detection. Individual morphine concentration-time curves were plotted for plasma and CSF and various pharmacokinetic variables were calculated. Plasma morphine concentrations after epidural injection were similar to those found after intramuscular administration; Cmax (66±8 mg/ml: mean±SEM) appeared within 12±3 min, and the terminal elimination half-life in plasma was 213±24 min. In CSF, morphine reached a peak (1575±359 ng/ml) after 135±40 min. The terminal elimination half-life for morphine in CSF was 239±10 min. The CSF bioavailability of morphine after epidural administration was calculated to be 1.9±0.5%. The study showed that epidural administration of morphine resulted in CSF concentrations many times higher than those in plasma, but still only 2% of the dose administered was available to the CSF compartment. Morphine was eliminated with similar speed from CSF and plasma.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00630291
