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Thermography in Anesthetic Peripheral Nerve Blocks When Using Different Local Anesthetics.
Andrejs Ernests Zirnis1,2, Aleksejs Miščuks1,2, Iveta Golubovska1,2
1Faculty of Medicine and Life Sciences, University of Latvia, LV-1004 Riga, Latvia.
Diagnostics (Basel, Switzerland)
|November 13, 2025
Summary
Thermography offers an objective way to assess nerve block success, showing temperature changes indicate effectiveness. This method requires at least 15 minutes post-block for reliable results in regional anesthesia.
Area of Science:
- Anesthesiology
- Medical Imaging
- Regional Anesthesia
Background:
- Peripheral nerve blocks are operator-dependent, with variable success rates.
- Current assessment methods rely on subjective patient feedback, which can be delayed or inaccurate.
- Objective, quantitative assessment of nerve block efficacy is needed.
Purpose of the Study:
- To evaluate thermography as an objective tool for assessing sciatic nerve block success.
- To compare the efficacy of different local anesthetics using thermography.
- To determine the optimal timing for thermographic assessment.
Main Methods:
- 55 patients undergoing sciatic nerve block with lidocaine, bupivacaine, or ropivacaine.
- Equipotent doses of local anesthetics were administered.
- Thermographic imaging of the anesthetized region for 45 minutes post-block.
Main Results:
- No significant differences in temperature changes were observed among the local anesthetics.
- Thermography requires a minimum of 15 minutes post-block for reliable assessment.
- Thermography's reliability is reduced in cases of acute bone fractures.
- Lower initial skin temperature correlated with a faster temperature increase.
Conclusions:
- Thermography provides an objective, quantitative measure of nerve block success.
- A 15-minute post-block interval is recommended for thermographic assessment.
- Thermography may be a valuable adjunct in regional anesthesia, with considerations for specific clinical scenarios like fractures.
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