The Skin-to-epidural distance of parturients by ultrasonography: sitting position versus left lateral position.
10.17085/apm.2017.12.2.132
- Author:
Eun Hee CHUN
1
;
Rack Kyung CHUNG
;
Youn Jin KIM
;
So Hee JIN
Author Information
1. Department of Anesthesiology and Pain Medicine, Ewha Womans University College of Medicine, Seoul, Korea. rkchung@ewha.ac.kr
- Publication Type:Original Article
- Keywords:
Epidural;
Obstetric;
Ultrasound
- MeSH:
Body Mass Index;
Observational Study;
Skin;
Spine;
Transducers;
Ultrasonography*
- From:Anesthesia and Pain Medicine
2017;12(2):132-136
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: Pre-procedural lumbar ultrasound scanning is a reliable tool to estimate the skin to epidural distance (SED). We conducted an observational study to compare the SED between the sitting position and lateral position using pre-procedural ultrasound imaging of the lumbar spine in parturients. METHODS: Using a 2–5 MHz curvilinear transducer, we obtained images of the lumbar interspaces from L2-3 to L5-S1 in the paramedian sagittal oblique view. The individual distance from the skin to the ligamentum flavum-dura mater unit was measured at the level of L2-3, L3-4, L4-5, and L5-S1 in the left lateral position (distance in lateral position; D-lat). Subsequently, participants were placed in the sitting position, and the distance was measured in the same manner (distance in sitting position; D-sit). Data were grouped according to body mass index (BMI; kg/m²) measurements of ≥ 25 or < 25 and analyzed. The primary outcome was the change determined by ultrasound between D-lat and D-sit at the same lumbar level according to position. RESULTS: Thirty parturients were studied. The difference between D-lat and D-sit in the same lumbar level was not statistically significant. The mean changes between D-lat and D-sit in the same lumbar level were less than 0.18 cm. In BMI ≥ 25 group, the difference between D-lat and D-sit were greater than that of BMI < 25 group at L3-4 level (P = 0.042). CONCLUSIONS: It is important for clinicians to consider that position change is associated with greater differences in SED in obese parturients (BMI ≥ 25) compared with thin parturients (BMI < 25). For obese parturients, the sitting position may be helpful.