310 Comparison of Ideal Needle Insertion Location for Internal Jugular Central Venous Access: Anatomic Landmarks versus Ultrasonography Guidance Method

Abstract

Study Objectives: Ultrasonography-guided central venous access of the internal jugular vein is considered superior to landmark-guided line placement. The use of ultrasonography has resulted in fewer attempts at line placement, shorter time for line placement and fewer complications. Current practice almost excludes using the landmark approach, except for patients in extremis undergoing emergent line placement. Complications of central lines are not uncommon and can be significant. Preliminary studies have shown conflicting data regarding the utility of US-guided access when compared to the “blind” or landmark approach to access. We were interested in determining whether or not there is a significant difference in the ideal needle insertion sites for the 2 methods of line placement. Methods: Our aim was to measure the distance between landmark and ultrasonography-guided needle insertion sites for internal jugular central line placement in a convenience sample of patients in our Level II urban academic emergency department (ED). Actual central line placement was not required. A convenience sample of 45 patients seen in the emergency department at Christus Spohn Memorial Hospital and were enrolled in this study from June to August 2011. Eligible participants include ED patients between the ages of 18 and 65 who were medically stable and able to be placed in Trendelenburg position without risks or complications. A study investigator, using anatomic landmarks in accordance with standard practice, drew an × on the skin with an invisible marker representing the location where the needle would be placed. Next, the second investigator, blinded to the first investigator's placement location, used bedside ultrasonography to identify the most ideal location for anterior approach for initial needle puncture by placing an ink mark in the exact location the initial needle puncture would have been placed in an actual line placement. The invisible pen marks were then illuminated with a black light and the distance between the “invisible” × and the ink was measured. The second investigator then also made note of the anatomical relationship of the carotid artery as compared to the internal jugular vein as well as any other anatomic variations. Results: Of the 45 sampled patients, 45% were found to reflect “normal” anatomy where the internal jugular lies lateral as compared to the carotid artery, 0% demonstrated the carotid artery superficial to the internal jugular, 55% demonstrated the carotid artery immediately deep compared to the internal jugular, and finally 0% were found to have a carotid artery more lateral when compared to the internal jugular. Measurements taken were found to have a range from 2.0 mm to as much as 150.0 mm with an arithmetic mean of 23.2mm and a standard deviation of 23.9. Seven of the 45 (15.5%) samples fell within the 5mm margin while the other 38 (84.5%) were greater than the acceptable 5mm margin for ideal initial needle insertion. Test value of 5.1 with a 95% confidence interval (10.8 to 25.2) and a significance level of P<0.0001. Conclusion: Ultrasonography guidance continues to be proven as a safer, more reliable, and more accurate means of placing central lines. This study reinforces the benefits of direct visualization to recognize the structural arrangement of the anatomy of the neck specifically that of the carotid artery and internal jugular vein, as well as identifying the most desirable location for initial needle insertion.