We all know the gold standard for confirmation of a CVP catheter is a chest x-ray. However, if that is not immediately available, has anyone heard of:
Confirmation via ECG?
or
Confirmation via doppler while injecting 10mL air?
I found some info discussing the use of premature beats on the ECG monitor to confirm CVP catheter placement. Didn't read too much about it but it seems study results varied, and the sensitivity of such a method would be low. It is however, possible it seems.
I could not find ANYTHING about confirmation via doppler while injecting air. Anyone know about this?
The 10 mL of air comment really scares me here. I too have heard (and done) bubble studies with TTE or TEE's, in which we use 1 mL of air and 10 mL's of saline, agitated with 2 syringes and a stopcock. But never for placement of a line.
That study is more for vascular flow, specifically looking for R to L shunting...
10 mL of air is more than enough to kill someone.....
the clinical use of a new ECG-guided central venous catheter with regard to positioning in the superior vena caves (SVC) was tested in some studies.
most of researcher observed an intra-atrial p-wave (p-atriale). then for extra confirmation of
Study Objective: To evaluate the clinical use of a new ECG-guided central venous catheter with regard to positioning in the superior vena caves (SVC).
Design: Prospective study.
Setting: Operating rooms of a university hospital and a general hospital.
Patients: 89 elective and emergency adult surgical patients requiring central venous catheterization perioperatively.
Interventions: We performed ECG-guided placement of the central venous catheter from several insertion sites. After we observed an intra-atrial p-wave (p-atriale), the catheter was withdrawn 3 cm back into the SVC. Postoperative anterior-posterior chest radiographs were performed for verification of tip localization.
the result of their study showed that the Use of this wire-conducted intravascularECG signal is a reliable tool for positioning the central venous catheter via various insertion sites.
Upper extremity vessel: Obtain an A/P chest X-ray with the arms in adduction and the head turned away from the side of placement. Successful central placement in the superior vena cava, (SVC) is above the pericardial reflection line. If the tip cannot be clearly visualized a right posterior oblique film, 20 degrees off midline) should be taken.
Lower extremity vessel: Obtain two X-ray views of the abdomen, one A/P and one cross table lateral. Successful central tip placement is in the inferior vena cava, (IVC)
Monitoring PICC line tip location during line maintenance:
Weekly and as needed monitoring of PICC lines with appropriate X-ray studies with discussion of current tip location in rounds and documentation when appropriate in the progress note.
Documentation of tip location when seen on routine X-rays in progress notes.
There is no confirmation method that can be used with 100% certainty
Transduce: This option is only available in the ICU. The small catheter found in the CVC kit, if not held firmly in place, may slip out of the vessel, making the guidewire impossible to pass and necessitating a second puncture.
Hold up pressure tubing: This may be misleading in patients with very elevated CVPs and This may increase the risk of air embolus
ABG/VBG Comparison: This may be misleading in patients with low flow states or severe hypoxemia.
Ultrasound Confirmation of Guidewire Placement
air flush usally is not part of today cliniccal practice
Yeah, the 10mL of air was from a test question. Guess it was a trick question, lol.
The 10 mL of air comment really scares me here. I too have heard (and done) bubble studies with TTE or TEE's, in which we use 1 mL of air and 10 mL's of saline, agitated with 2 syringes and a stopcock. But never for placement of a line.
That study is more for vascular flow, specifically looking for R to L shunting...
10 mL of air is more than enough to kill someone.....
Of bigger concern to me is the question of where in the US would we be placing CL's without immediate use of a CXR machine...I mean, it is 2011 here...
And as far as the 10 ml of air question...I pity the soul stupid enough to even consider such a dumb idea!
aquaphone
46 Posts
Wow. Thanks for sharing, I had no idea!