A new way to determine correct depth of central venous catheter insertion using a real-time ultrasound guided insertion technique in pediatric patients.

In this paper, the authors have attempted to determine a practical way to predict the ideal CVC depth of insertion using an ultrasound-guided insertion technique. They retrospectively analysed the data from 386 patients with congenital heart defects undergoing surgery. Children had been cannulated using either the right internal jugular vein approach, left supraclavicular approach or right supraclavicular approach. The skin was punctured at the level of the thyroid cartilage in the right internal jugular vein approach. The puncture for the supraclavicular approaches occurred as close to the probe using the long-axis (in plane) view keeping the confluence of the internal jugular and ipsilateral subclavian vein in the centre of the image. The ideal CVC depth in this study was determined to be that whereby the CVC tip is at the level of the carina on the first post-operative chest x-ray.

The study demonstrated that the insertion depth using the right internal jugular and left supraclavicular approaches were similar, whereas the depth for the right supraclavicular approach was significantly shorter. The authors were able to identify an ideal insertion depth as a percentage of the patient’s height for every 10cm increase in body height (see Figure 3 within the article).

Take home message

This study shows that there is a relationship between the body height and insertion depth of CVCs in children with congenital heart defects having cardiac surgery. While children with no cardiac disease were not studied in this paper, the graph in figure 3 may be used as a guide for those who do not regularly insert CVCs in children.

Reviewed by: Dr Scott Ma