By Samuel Nadler, MD, PhD

Critical Care, Pulmonary Medicine, The Polyclinic Madison Center, Seattle; Clinical Instructor, University of Washington, Seattle

Dr. Nadler reports no financial relationships relevant to this field of study.

SYNOPSIS: Catheter misplacement and pneumothorax after routine ultrasound-guided catheter placement are rare, and routine post-procedural chest radiographs may not be cost-effective.

SOURCE: Chui J, Saeed R, Jakobowski L, et al. Is routine chest X-ray after ultrasound-guided central venous catheter insertion choosing wisely? A population-based retrospective study of 6875 patients. Chest 2018 Feb 28. pii: S0012-3692(18)30341-6. doi: 10.1016/j.chest.2018.02.017. [Epub ahead of print].

Chest radiographs are performed routinely after central venous catheterization to confirm appropriate placement and evaluate for procedural complications such as pneumothorax. With the increased use of ultrasound-guided placement, the procedural risks have decreased, raising concerns about whether routine radiographs remain cost-effective.

Chui et al conducted a retrospective analysis of all adult patients in an academic center who received a central line in the operating room. Patients were excluded if they underwent cardiothoracic surgery, received a femoral line, or did not undergo a post-procedural chest radiograph.

The authors identified a cohort of 6,875 patients and determined the incidence of pneumothorax and catheter misplacement. The most common site of placement was the right internal jugular vein (85%), followed by the left internal jugular (6%), and the subclavian veins (4% each side). A short (15 cm) central venous line was used most commonly (99%), with few pulmonary artery catheters (< 1%) or large-bore central venous catheters placements (< 1%).

The overall rate of pneumothorax was 0.33%, with 0.12% of patients requiring chest tube placement. The strongest risk factor for pneumothorax with multivariate analysis was a left subclavian site (odds ratio, 6.58; P < 0.001). Catheter misplacement occurred in 1.91% of procedures, most commonly with coiling in superior vena cava/subclavian/innominate vein (53%), most of which did not require repeat chest radiograph for repositioning (82%). Use of a site other than the right internal jugular vein was associated with an increased risk of misplacement.

Assuming the cost of a chest radiograph of $115-$200 per film, the cost to diagnose one pneumothorax was $34,375-$59,783, while the cost to diagnose a misplaced catheter was $6,043-$10,496. When considering only post-procedural complications requiring interventions, the number needed to test for pneumothorax was 860 at a cost of $98,828-$171,875 per chest drainage. For catheter misplacement, the number needed to test was 286, with a cost of $32,942-$57,292 per catheter repositioning.

COMMENTARY

Chui et al examined the likelihood of complications from central venous catheterization and the costs associated with chest radiographs to screen for these complications. The relatively large number of patients examined is a strength of this study. However, generalizing this study creates a few limitations. First, all the central lines were placed in the operating room with ultrasound guidance under ideal conditions in surgical patients. Complication rates in other settings, such as the ICU or general medical ward, may be higher, and the need for interventions for pneumothorax or catheter misplacement may be greater with prolonged mechanical ventilation and catheter use. Second, a short central catheter (15 cm) was used, which reduces the likelihood of coiling. Third, this was a single institution study, with ultrasound guidance widely available for central line placement.

With these caveats, a few conclusions can be drawn. Catheterization in the right internal jugular vein using ultrasound appears to carry a low complication rate. When pneumothorax or catheter misplacement was noted, most complications did not require additional intervention. Furthermore, other techniques to determine pneumothorax and catheter placement, such as thoracic ultrasound, are available. For pneumothorax specifically, ultrasound may be more sensitive.

In short, the cost of routine chest radiographs that change management is quite high, and routine post-procedural chest radiography may be unnecessary and a poor use of resources.