Optimal insertion depth of subclavian vein catheterization via the right supraclavicular approach in children

Background Methods to determine the optimal insertion depth of ultrasound-guided supraclavicular approach to the subclavian vein (SCV) catheterization, alternatively used for central venous access, are debatable in children. Aim We investigated the applicability and reliability of the modified formula for determining the depth of SCV catheterization using an ultrasound-guided supraclavicular approach in children. Methods This prospective observational study included 36 children (age <6 years; weight >= 5 kg) scheduled to undergo congenital heart disease surgery. After intubation, ultrasound-guided supraclavicular approach to the SCV catheterization was performed. Actual insertion depth was determined by real-time transesophageal echocardiography. Insertion depth was calculated by subtracting 1 cm from the sum of the distance from the insertion point to the sternal head of the right clavicle and that from the latter point to the midpoint of a perpendicular line drawn from the sternal head of the right clavicle to the line connecting the nipples. Results Insertion depth calculated with the modified formula and actual insertion depth of the SCV catheter correlated strongly (r = .806, 95% confidence interval [CI]: 0.658-0.908; p < .001). Bland-Altman analysis showed a mean bias and precision of 0.36 and 0.65 cm, respectively (95% CI: 0.14-0.58, 95% limits of agreement: -0.92, 1.64). All plots were above the -1.0 line, indicating no catheter tip insertion into the right atrium. Conclusions Optimal insertion depth for an ultrasound-guided supraclavicular approach to the SCV catheterization can be calculated using modification of a surface landmark formula in children younger than 6 years and weight heavier than 5 kg.