A high frequency linear probe was used to find an area of the subclavian (or sometimes axillary) vein in long axis (more on axis choice later) that was amenable to catheterization and that passed over a thoracic rib.Ultrasound evaluation of the ipsilateral and contralateral subclavian and axillary veins, both with infraclavicular and supraclavicular approaches looking for anatomic findings which may portend difficult placement.The study included four key steps that may have contributed to the few mechanical complications experienced: These results are obviously impressive and prompt a close look at the description of their technique (important to note: all providers had >6 years’ experience in central line placement). Pneumothorax occurred 4.9% of the time in the landmark group and zero times in the ultrasound group. So, can ultrasound reduce the feared mechanical complications of the subclavian site? A 2011 randomized controlled trial compared just this: landmark vs ultrasound-guided subclavian central catheter placement. Of note, ultrasound guidance was not protocolized for this trial, a significant number of the lines were placed by landmark technique, and the analysis showed an interaction between mechanical complications and not using ultrasound. Pneumothorax accounted for most of the mechanical complications with occurrences of 1.5% (subclavian), 0.5% (IJ), and 0% (femoral). This was significantly more than the femoral site but not statistically significant when compared to the IJ. These complications did occur more frequently for the subclavian site when compared to both other sites. Mechanical complications were treated as a composite as well, and included pneumothorax, arterial injury, and hematoma. Interestingly, the subclavian site was significantly better when compared to both the IJ and femoral sites for this outcome. The randomized controlled trial, 3SITES, compared femoral vs internal jugular vs subclavian venous access, with the primary outcome being a composite of blood stream infection and DVT. Is this what the evidence shows? Why does the CDC recommend the subclavian site as the site of choice for temporary non-tunneled central lines, 3 and why don’t we follow this advice? 1,2 Interns and medical students are often taught that the femoral site has higher rates of infections, and the subclavian is technically difficult and risks the development of a pneumothorax. Is there a “best” site? Looking at some retrospective studies and meta-analyses, there is a suggestion that the internal jugular (IJ) is by far the most common site for central venous cannulation. Is a C-collar in place? Are the endotracheal tube straps in the way? Is there an overlying cellulitis of the groin? Will a large pannus make a femoral approach difficult? Is this line emergent and is an ultrasound readily available? Does the patient already have a pneumothorax or chest tube? Suffice to say, there are many reasons a site may or may not be ideal - so it is good to have choices. Often logistical concerns can contribute to our choice as well. Infection rates, risk of bleeding, risk to surrounding structures, incidence of deep venous thrombosis (DVT), and specific complications such as pneumothorax are all things to consider. When deciding which of the three typical sites (internal jugular, femoral, and subclavian) to choose for central venous access, much can go into the site selection. The need for a central line is commonplace in the emergency department and critical care units.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |