Ultrasound to Confirm Central Venous Catheter Placement
Dr. Daniel Eggeman
edited by Ilyas Taraki
Background
In the intensive care units and emergency department, it is crucial to confirm central line placement to rule out procedural complications (pneumothorax, carotid injury, etc.) and to begin administration of life-saving medications (pressors to improve end organ perfusion). The faster this can occur, the better for the patient.
Recently, I was frustrated by my reliance on the portable x-ray for confirmation, because it was often gone from the ICU for prolonged periods of time.
Is there a way I can confirm central line placement at the bedside using ultrasound?
Article
Saul T, Doctor M, Kaban NL, Avitabile NC, Siadecki SD, Lewiss RE. The Ultrasound-Only Central Venous Catheter Placement and Confirmation Procedure. J Ultrasound Med. 2015 Jul;34(7):1301-6. doi: 10.7863/ultra.34.7.1301. PMID:26112635
Study Design
Literature review of multiple studies. This paper focused on developing point-of-care ultrasound protocol for 3 aspects of central venous catheter placement above the diaphragm:
Dynamic procedural guidance
Evaluation for pneumothorax
Confirmation of the catheter tip location
Results
Dynamic procedure guidance resulted in fewer complications (eg. arterial puncture and pneumothorax), fewer cannulation attempts, and decreased procedure duration.
Multiple studies demonstrate that lung US is more sensitive than supine AP CXR for pneumothorax.
Injection of microbubbles can confirm that the catheter tip is in the inferior third of the superior vena cava (see figures left).
Summary
US allows for faster confirmation of line placement at a decreased cost to patient.
Patient is not subjected to ionizing radiation and does not need repositioning.
US shown to be better than CXR for detection of pneumothorax.
Saline flush will reveal line in venous systems, even in distorted anatomy.
Application
Due to its novelty/comfort level, I will continue to use chest x-ray as a confirmatory test for central lines as I practice this protocol.
The goal will be to have a backup in times of crisis when the x-ray is not available and critical medications are needed emergently.
Ideally one day, this will be my primary method to confirm central lines are in the correct location.