ABSTRACT
In patients who require a permanent central venous catheter (PCVC), the usual aim is to put the catheter tip at the superior vena cava and right atrium (SVC-RA) junction. However, there is no study regarding how to guide the positioning of the catheter tip when the SVC-RA junction cannot be identified on chest radiograph. The objectives of this prospective study were: (1) to investigate the incidence and etiologies of radiographically undetermined SVC-RA junctions in cancer patients undergoing PCVC implantation; and (2) to evaluate the feasibility, effectiveness and safety of combined transesophageal echocardiography (TEE) and laryngeal mask airway (LMA) to guide the positioning of catheters during implantations in patients without this radiographic landmark. Over a 1-year study period, 83 consecutive patients with oncologic diseases who required implantation of a PCVC in a tertiary center were screened. Their preoperative chest radiographs were examined by radiologists to identify the presence of the SVC-RA junction. Patients without a radiographically identifiable SVC-RA junction were classified as cancer-related or cancer-unrelated in terms of etiology. For patients without this landmark, we used TEE with a pediatric biplane transducer and a LMA under intravenous general anesthesia during PCVC implantation to guide the positioning of the catheter tip at the SVC-RA junction. We found that in 16% (13/83) of patients, the SVC-RA junction could not be identified on radiograph. Among the 13 patients, only three (23%) had cancer-related etiologies. In all of the 13 patients, the LMA was successfully placed after the TEE transducer was inserted. No episode of air leak from the LMA was found during surgery. All had the catheter tip positioned in the anatomic SVC-RA junction under TEE guidance. In conclusion, 16% of cancer patients requiring PCVC implantation had no identifiable SVC-RA junction on chest radiograph and most causes were cancer-unrelated. In patients without a radiographically identifiable SVC-RA junction, guidance by TEE under LMA general anesthesia is a feasible, safe and effective management to position a PCVC at the SVC-RA junction.
