It doesn't matter because you will never be able to aspirate air.What Is the correct location of central venous catheter tip for a VAE?
What Is the correct location of central venous catheter tip for a VAE?
Miller states that if it is a multi orifice it should be placed 2cm below the junction and if single orifice it should be 3cm above the junction. pg 1908I hear you. Unfortunately I've seen this topic on my last 4 intraining examinations. I bet I'll see it next week.
I think what they are getting at is if you have an "air lock" and consequently acute right heart failure. So IVC is incorrect. Junction of IVC and RA is also incorrect as it will do nothing. Now other options would be
2. RV outflow tract
I'm wanting to say RVOT, but I'm not sure and I have not read this anywhere.
Then there was this oneA flexible Silastic casting of the human right atrium was developed to correspond to some in vivo human right atrium hemodynamic characteristics including chamber pressures, pulsatility, fluid output, and flow velocity. Using an infusion pump, air was introduced (10 ml in 30 s) into the superior vena cava of the model and aspirated via a catheter from different positions within the model atrial chamber. The tests were carried out at atrial inclinations of 60 degrees, 80 degrees, and 90 degrees from the horizontal and compared the aspiration efficiency of a single-orificed 16-gauge catheter to a 16-gauge multiorified (5 aperatures) catheter. Optimal air aspiration occurred with the multiorificed catheter tip positioned within the area 2.0 cm below the junction of the superior vena cava (SVC) and the atrial chamber at an inclination of 80 degrees. As much as 80 per cent of the incoming air could be aspirated under these conditions. At its optimal position the single-orificed catheter gave a maximal yield of 45 to 50 per cent aspiration when the tip was positioned 3.0 cm above the SVC and atrial chamber junction. Aspiration of air from mid right atrium (4.5 cm below the SVC-atrial junction) was poor regardless of the type of catheter used or atrial inclination. These data suggest a need for reappraisal of catheter design and placement.
Personally, I think that if you have an air embolism you should advance the catheter as far as is reasonable and suction on the way out. Stop when you find a pocket of air and suction until you only get blood back. Repeat.STUDY OBJECTIVE: To test the relative efficiency of balloon-tipped and plain catheters for aspiration of venous air embolism.
DESIGN: The following four single-lumen central venous catheters were studied in a silastic model of the right atrium, tricuspid valve, and vena cavae: (1) the 16-gauge single-orifice catheter; (2) the 14-gauge Bunegin-Albin multiorifice catheter; (3) the 7-Fr pulmonary angiography catheter with balloon distal to orifices; (4) the 7-Fr pulmonary angiography catheter with balloon proximal to orifices. A 10% glycerol-water solution was circulated at 3.7 to 4.0 L/min. Catheter tips were positioned at 1 cm increments from -3 to +3 cm around the superior vena cava-right atrial junction with cardiac inclinations of 65 degrees and 80 degrees. Air (10 ml) was infused over 30 seconds; aspiration from the test catheter began 5 seconds later at 40 ml/min for 75 seconds. The balloon catheters were evaluated with the balloons inflated and deflated.
MEASUREMENTS AND MAIN RESULTS: Amounts of air aspirated were compared by analysis of variance and Tukey's multiple comparison, p less than 0.05, for all combinations. The 16-gauge single-orifice catheter tested best at a 65 degrees cardiac inclination with 86% of the venous air embolism recovered, while the 14-gauge Bunegin-Albin multiorifice catheter tested best at an 80 degrees cardiac inclination with 62% of the venous air embolism recovered. Both catheters functioned most efficiently at or above the superior vena cava-right atrial junction.
CONCLUSIONS: This study demonstrated that efficacy of air recovery depends on catheter type, catheter tip position, and cardiac inclination. No benefit was derived from positioning the catheter tip inside the atrium or from using balloon-tipped catheters.
Damn.In dire circumstances, a needle can be inserted through the anterior chest wall and into the right ventricle to aspirate the air. (This can be accomplished by inserting a long needle in the 4th intercostal space just to the right of the sternum and advancing the needle under the sternum at a 45 degree angle until there is blood return.)