The Method to Increase the Ratio of Location of a Catheter in the Superior Vena Cava by Subclavian Cannulation / 대한마취과학회지

BACKGROUND: Subclavian cannulation is useful for the patients who need long-term maintenance of central venous catheters, but the inadequate location of catheters produces some complications. In pediatric populations, the abnormal placement of subclavian catheters in the internal jugular vein (IJV) is frequent because the angle formed by the subclavian vein and IJV is much larger than in adults. We would therefore propose a technique which will increase the location ratio of subclavian catheters in the superior vena cava (SVC). METHODS: One hundred twenty three patients who received elective or emergent operations were divided into 4 groups which consisted of the 'neck rotation away from the cannulation site' group (RA), 'neck rotation toward the cannulation site' group (RT), 'neck tilt away from the cannulation site' group (TA), 'neck tilt toward the cannulation site' group (TT). We cannulated each group and verified the location of the catheter tip in chest PA for each group. RESULTS: The calculation for the ratio of SVC location to the total cannulation of each group (%SVC) was done and the X2 test was done. Total %SVC was 73.2% and %SVC of each group were 64.9% for the RA group, 77.3% for the RT group, 61.8% for the TA group, and 93.3% for the TT group. A considerable difference was found for total %SVC in the X2 test. The location ratio of the TT group was higher than the others and there was no difference found between the RA, RT, TA groups. CONCLUSIONS: We can conclude that tilting the neck toward the cannulation site would produce a higher ratio of SVC location of the subclavian catheter than other neck positions.

Estimation of the Optimal Depth of Subclavian Catheterizations in Pediatric Patients / 대한마취과학회지

BACKGROUND: The optimal depth of subclavian catheterization is not clearly and simply defined in the pediatric population. The aim of this study is to examine the relationship between the depth of the subclavian catheter and easily measured body-size variables, such as weight and height, and then to formulate a guide for the optimal depth of subclavian catheterization in the pediatric population. METHODS: We cannulated eighty-five pediatric cardiac patients via the left or right subclavian approach. The position of the catheter tip was determined by postoperative AP chest x-ray, and the length from the skin to the point of the border of superior vena cava and the right atrium (SK-SVCRA) was measured. RESULTS: Significant correlations with SK-SVCRA were found for weight and height. For the right approach, SK-SVCRA is calculated as 0.28xweight (kg) + 4.86 or 0.07 x height (cm)+1.70. For the left approach, SK-SVCRA is calculated as 0.22xweight (kg)+6.51 or 0.06xheight (cm)+3.94. CONCLUSIONS: Simple equations for the placement of the catheter tip at the border of the superior vena cava and right atrium as a function of patients' weight and height were formulated. These data may provide a useful guide to determine how deeply the subclavian catheter should be located.