Document Detail


Blood pressure, but not cerebrospinal fluid fentanyl concentration, predicts duration of labor analgesia from spinal fentanyl.
MedLine Citation:
PMID:  19996953     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: There is a wide variability in dilution of drugs in cerebrospinal fluid after spinal injection, as measured near the site of injection. With local anesthetics, there is a wide variability in speed of onset, which correlates with block duration. The authors tested whether local cerebrospinal fluid drug concentrations and onset time would predict duration of analgesia from spinal fentanyl in laboring women. METHODS: After written informed consent, fentanyl (50 microg) was injected using the combined spinal epidural method in 56 women requesting analgesia for labor. The stylet was reinserted in the spinal needle, and 60 s later, the cerebrospinal fluid was aspirated for fentanyl assay. Time to analgesia and duration of analgesia were recorded, and data were analyzed by linear regression. RESULTS: Fifty-two women were included for data analysis. The cerebrospinal fluid fentanyl concentrations were 3.1 +/- 5.9 microg/ml, with a 7-fold range (0.9-5.9 microg/ml). Fentanyl concentration did not correlate with onset, initial sensory level at 5 and 10 min, or duration of analgesia. Decreased diastolic and increased systolic blood pressure and lower parity, but not fentanyl concentrations, correlated with longer labor analgesia. The resultant model was predictive when applied to data from four previous studies of spinal opioid analgesia duration. CONCLUSIONS: Contrary to our hypothesis, the local concentration of fentanyl in the cerebrospinal fluid 1 min after injection was not correlated with onset or duration of labor analgesia. The unexpected but consistent relationship between blood pressure and combined spinal epidural analgesia duration suggests that resting hemodynamic state affects the distribution and/or clearance of intrathecally administered opioids.
Authors:
Kenneth E Nelson; Timothy T Houle; James C Eisenach
Related Documents :
10071993 - Arterial oxygenation during one-lung ventilation: combined versus general anesthesia.
15933283 - Crisis management during anaesthesia: tachycardia.
1447103 - Ventilation is stimulated by small reductions in arterial pressure in the awake dog.
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural    
Journal Detail:
Title:  Anesthesiology     Volume:  112     ISSN:  1528-1175     ISO Abbreviation:  Anesthesiology     Publication Date:  2010 Jan 
Date Detail:
Created Date:  2009-12-24     Completed Date:  2010-01-12     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  1300217     Medline TA:  Anesthesiology     Country:  United States    
Other Details:
Languages:  eng     Pagination:  174-80     Citation Subset:  AIM; IM    
Affiliation:
Department of Anesthesiology, Wake Forest University School of Medicine, NC, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Analgesia, Epidural
Analgesia, Obstetrical*
Anesthetics, Intravenous / cerebrospinal fluid*,  pharmacokinetics*
Blood Pressure / physiology*
Female
Fentanyl / cerebrospinal fluid*,  pharmacokinetics*
Heart / drug effects,  physiology
Humans
Labor, Obstetric
Multivariate Analysis
Predictive Value of Tests
Pregnancy
Reproducibility of Results
Spinal Cord / metabolism*
Treatment Outcome
Grant Support
ID/Acronym/Agency:
GM48805/GM/NIGMS NIH HHS
Chemical
Reg. No./Substance:
0/Anesthetics, Intravenous; 437-38-7/Fentanyl

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Cerebrospinal Fluid and Spinal Cord Distribution of Hyperbaric Bupivacaine and Baclofen during Slow ...
Next Document:  Randomized study assessing the accuracy of cervical facet joint nerve (medial branch) blocks using d...