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Determination of the optimal angle for needle insertion during caudal block in children using ultrasound imaging
1Department of Anaesthesiology and Pain Medicine, Kangdong Sacred Heart Hospital, Hallym University, Seoul, Korea.
Insights
Determining the optimal needle angle for pediatric caudal epidural injections is crucial. Ultrasound imaging suggests a 20-degree insertion angle to prevent bone puncture and intra-osseous injection in children.
Area of Science:
- Pediatric Anesthesiology
- Medical Imaging
- Interventional Pain Management
Background:
- Caudal epidural injections are common in pediatric pain management.
- Accurate needle placement is essential to avoid complications.
- Ultrasound guidance can improve procedural accuracy.
Purpose of the Study:
- To determine the optimal needle insertion angle for pediatric caudal epidural injections using ultrasound.
- To identify anatomical landmarks for safe needle entry.
- To correlate needle angle with patient demographics.
Main Methods:
- Ultrasound imaging of the sacral hiatus in 130 children (2-84 months) under general anesthesia.
- Measurement of intercornual distance, caudal space depth, and skin-to-bone distance.
- Calculation of the optimal needle insertion angle.
Main Results:
- Median intercornual distance: 17.0 mm, caudal space depth: 3.5 mm, skin-to-bone distance: 21.0 mm.
- Optimal needle insertion angle: 21.0 degrees.
- No significant correlation found between optimal angle and patient age, weight, height, or body surface area.
Conclusions:
- A needle insertion angle of approximately 20 degrees is recommended for pediatric caudal epidural injections.
- This angle aims to prevent bone puncture and potential intra-osseous injection.
- Ultrasound is a valuable tool for guiding needle placement in this procedure.
Abstract:
Using ultrasound imaging, the optimal angle for needle insertion during caudal epidural injection in children was estimated. After general anaesthesia, ultrasonography was performed at the sacral hiatus in 130 children aged 2-84 months positioned in the lateral position. The median [range] values for the intercornual, caudal space depth and the distance from skin to the posterior sacral bony surface were 17.0 [9.6-24] mm, 3.5 [1-8] mm and 21.0 [10-39] mm, respectively. The optimal angle showed no significant correlation with age, weight, height or body surface area. The median [range] calculated optimal angle for the needle was 21.0 [10-38] degrees. We conclude that the needle should be inserted at about 20 degrees to the skin to avoid puncture of the bone and potential intra-osseous injection.
