Placing Central Venous Catheters: Gold Standard for Adult and Silver Standard for Pediatric Patients?

Abstract

In Response: Drs. Reich and Booke correctly describe the inaccuracy of our figure 1. (1) The arrow for site 1 indeed should be slightly more caudad to be exactly midway between the sternal notch and mastoid process, as we had intended, and where the central venous catheters (CVCs) were placed in our study. We dispute the assertion that the mastoid process and sternal notch are weak anatomical landmarks. They are well defined in patients of all ages, in contrast to muscular or cartilaginous landmarks in infants, which are often indistinct and obscured by adipose tissue. They refer to the ECG guided technique as the gold standard to assure correct placement of the CVC tip. A gold standard should be widely known, proven, utilized, and readily evident in textbooks. Perusal of the chapters on CVC placement in the most recent editions of two leading adult anesthesia textbooks, one general and one cardiac (2,3), reveals no mention of the technique. Thus it cannot, in our opinion, be considered the gold standard for placement of CVC in adult patients. Their cited references (4–8) document over 1000 CVC placements in pediatric patients with variations of the ECG guided technique, either by saline-filled catheter, or by using the J-wire to transmit the intra-atrial ECG. The largest series of 807 patients (6) contains very few details about the patients but does make the point that the ECG guided technique cannot be used in patients with “serious irregularities of rhythm or cardiac malformations.” None of the other references specifically mentions patients with congenital heart disease. Thus, although the success rate of intra-atrial ECG guidance for CVC placement is well over 90%, these patients had normal hearts. Although there are no controlled studies reported, the ECG guided method would not appear to be superior to our height and weight based formulae, which require no special equipment, (i.e sterile ECG leadwire with alligator clip to obtain an intracavitary ECG), and predict correct placement 97% and 98% of the time, respectively. To our knowledge, the ECG guided technique has not been validated in patients with enlarged atria, which the majority of our patients had. This gives rise to enlarged or biphasic P waves on surface ECG (9), which could change the progression of P wave enlargement as the guide wire is advanced into the atrium, rendering ECG guidance less useful. Dean B. Andropoulos, MD Stephen A. Stayer, MD