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Labor epidural analgesia without an intravascular "test dose"
M C Norris1, S T Fogel, H Dalman
1Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. Norrism@notes.wustl.edu
Anesthesiology
|June 24, 1998
Summary
Aspiration and observation effectively detect intravascular placement of epidural catheters, preventing local anesthetic toxicity. This method is safe for labor analgesia when using multiple-orifice catheters and dilute solutions.
Area of Science:
- Anesthesiology
- Obstetrics
- Pain Management
Background:
- Epidural catheter placement is crucial for labor analgesia.
- Intravascular catheter placement can lead to local anesthetic toxicity.
- Detecting intravascular placement is essential for patient safety.
Purpose of the Study:
- To prospectively evaluate the efficacy of aspiration in detecting intravascular placement of multiple-orifice epidural catheters.
- To assess the safety and effectiveness of labor analgesia using this detection method.
Main Methods:
- 1,029 laboring women received multiple-orifice, 20-gauge epidural catheters.
- Catheters were observed and aspirated for blood/CSF before testing with local anesthetic.
- Labor analgesia was induced with dilute local anesthetic and opioid if tests were negative.
Main Results:
- Aspiration and observation identified 60 intravenously placed catheters.
- The incidence of false-negative aspiration results was very low (0.2% to 0.4%).
- No patients experienced signs or symptoms of local anesthetic toxicity.
Conclusions:
- Aspiration and incremental drug injection are effective safeguards against intravascular epidural catheter placement.
- This technique is safe under the study conditions (multiple-orifice catheters, dilute solutions).
- Results require further study before extrapolation to different clinical settings.
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