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.