PURPOSE: Cervical subcutaneous fat thickness (SCFT) separating the skin and the internal jugular vein (IJ) varies widely between patients, with values ranging from less than one cm, up to 5 cm. There are no studies assessing the need to adjust the depth of insertion (DI) of central venous catheter (CVC) in relation to SCFT for safe placement. The aim of this study is to evaluate the effect of SCFT and other factors on IJ CVC placement.
METHODS: This is a prospective observational study done at the intensive care units of the University of Oklahoma Medical Center. All patients requiring CVC placement in the IJ position were eligible. Safe placement was defined as a catheter tip above pericardial reflection or 2.7 cm above carina.SCFT was measured using Site∼Rite® 4 (Bard Access Systems, Salt Lake City). Weight, height, DI, distances between skin insertion and ipsilateral clavicle, as well as the radiographic distance between tip of the catheter and the carina were recorded.
RESULTS: A total of 25 patients were enrolled (13 males, 12 females). The average age was 53±15 years. Twenty IJ catheters were inserted on the right. Mean BMI was 31.4±10.5 Kg/m2. Mean SCFT was 2.1±0.8 cm (range: 1–4.5 cm). The DI ranged from 13 to 20 cm (average 15.6±1.6 cm), with the distance to the ipsilateral clavicule ranging from 2 to 7 cm.The SCFT significantly correlated with BMI (R2=0.59). The catheter tip to carina distance (DisT-Ca) did not correlate with the DI (R2=0.09). Correcting for the distance to clavicle did not improve this correlation. However, the correlation improved after correcting the DI for the SCFT (R2=0.28), and the BMI [DisT-Ca = −0.95(DI-BMI/5) + 8.7, R2=0.42].
CONCLUSION: Central line placement in the IJ position is best achieved when the depth of insertion is adjusted to the BMI. Measuring the Cervical subcutaneous fat does not improve the accuracy of the line placement.
CLINICAL IMPLICATIONS: To achieve a safe IJ central venous line placement, the depth of insertion should not exceed 6+BMI/5 cm.
DISCLOSURE: Houssein Youness, No Financial Disclosure Information; No Product/Research Disclosure Information