Archive for the ‘vascular access’ Category

Conventional teaching for treatment of confirmed or suspected tension pneumothorax in an unstable patient is immediate chest decompression with a large bore angiocatheter [1]. New generation angiocaths feature blood control technology, which allows a flash of blood to rise into the hub but will not transmit that blood out the end, which increases safety and decreases messes. Half of the departments I work in now stock blood control angiocaths; since this device is more expensive than its predecessors, you can expect all american hospitals will soon move to them. Notice the blood control valve, which adds length to the hub compared to the same catheter without this feature.     The blood control valve prevents blood from flowing out the hub but also prevents any other fluid from flowing through the catheter, including air. So stabbing your pneumothorax patient with this device will not decompress the chest. Fortunately the valve opens permanently when it is pushed down by IV tubing, or by attaching a syringe.   So place the angiocath as usual, then take a syringe, pull out the plunger, and twist it firmly onto the hub, until you hear your rush of air. There are all sorts of problems with using any needle or angiocath to decompress pneumothorax, especially if you use the usual anterior approach, and you are better off in most cases performing a finger thoracostomy or quickly placing a chest tube. But if you do use an angiocath, be mindful of blood control technology, because if you place a catheter thinking you’ve relieved tension but…

Most of us were taught to place central lines using the wire through needle Seldinger technique, but using the introduction catheter instead of the needle makes successful wire insertion more likely and facilitates venous confirmation. A 7 minute screencast. on vimeo operating room video of wire through catheter technique. recommend viewing at 2x speed. Update 1 Lee 2015 compares wire through needle and wire through catheter and shows that wire through needle is (slightly) better. The operators were anesthesiologists very experienced in central line insertion, which may account for their results. In the less controlled ED environment, with providers who don’t place a lot of lines (especially learners), the tendency of the needle to move before the wire can be transmitted may be more important. Also they did not confirm venous location in this study, which should be done whenever feasible and is greatly facilitated by the wire through catheter technique. Still, I’m aware of no data comparing the two techniques other than this (which appeared a few weeks after I posted the video), so though my success rate is definitely higher since I switched to wire through catheter, your mileage may vary. Update 2  There are two advantages of the wire through needle (conventional approach): the needle is functionally slightly longer than the catheter, and the needle doesn’t kink. Neither of these advantages make a difference at the IJ site, and where I work almost all lines are IJ, so I didn’t mention this in the video. Based on feedback, I am surprised (and pleased) at how many non-IJ lines are…

Peripheral line in central vein

November 26th, 2009
by reuben in vascular access

Does a 48 mm single-lumen angiocath in a central vein assume the infection risk of a central line or a peripheral line? Stated differently, does the infection risk of a central line stem from the line itself, the vein, or some other factor? Many of us who trained without ultrasound are very adept at cannulating the subclavian vein by landmarks. To be able to place a simple angiocath into a central vein in non-sterile fashion would be very convenient in difficult access patients. I can’t advocate for this unproven maneuver at large, but it may have a role in patients who need vascular access expediently but don’t need a central line, perhaps as a bridge to a conventional peripheral line or a formal central line. Journal of Emergency Medicine 37:4 p419

Excerpted from MSSM M&M teaching points: * Accidental arterial cannulation is usually benign but should be detected before dilation to avoid significant vessel injury. When performing an ultrasound-guided central line, the point where the needle tip enters the vein must be in the visualized ultrasound field. This may be accomplished by entering the skin with the needle a short distance away from the probe, rather than immediately adjacent to the probe, which will lead to the tip entering the vein out of the vertical plane visualized on the screen. Alternatively, the tip of the needle can be tracked into the vein by sliding the probe along the skin as the needle tip approaches the vein, keeping the tip in the visualized ultrasound field. * If venous placement is not certain, verification may be performed using a number of techniques. **A quick blood gas may be helpful if the PaO2/SaO2 values are conclusive; unfortunately blood gas results may lie in between definitively arterial and venous values. ** Transducing the pressure waveform is effective but takes time to set up. ** A brief and definitive technique uses a quick pressure column setup as follows: 1. Insert the guidewire, remove the needle. 2. Slide the conventional angiocath that comes in all central line kits over the wire, remove the wire. 3. Attach an extension set to the angiocath. An extension set comes in the introducer kit for this purpose. For triple lumen kits, ask the nurse to give you an extension set, or use the circular plastic sheath…

Intraosseous Tips

November 25th, 2009
by reuben in vascular access

Agree with previous rave reviews in terms of ease of use, success rates, reliability. I would add, as far as pain is concerned, that I have used this device in quite a few awake infants and young children. We see a tertiary population, often with underlying disease making PIV access difficult; I have personally watched the pain response in these patients to PIV attempts, and have found it much LESS painful to insert an EZ IO in awake patients. We have done this without local infiltration with lidocaine. One key is NOT to start and stop the drill as it goes through the skin – I have seen residents do this and it twists the skin which hurts. As long as the trigger is held until the needle is in the bone, patients cry much less than they do with PIV placement. The caveat, however, is that infusion through the IO definitely appears painful. We now routinely instill 1cc of 1% lidocaine through the IO, then wait 2 minutes before pushing fluids (this isn’t necessary, of course, in an emergent resuscitation of an unconscious patient). Another technique is to put 2-3 cc of 1% lidocaine in the bag of IVF that you are infusing which seems to decrease infusion pain well. Garth Meckler, MD, MSHS Fellowship Director and Assistant Section Chief Pediatric Emergency Medicine Oregon Health & Science University       For adult patients that respond to painful stimuli, slowly administer 40 mg of lidocaine (2 ml) of 2% lidocaine for cardiac use prior…

standard pink IV: 20 gauge (.8 mm) x 30 mm angiocath max flow rate = 60 ml / minute standard green IV: 18 gauge (1 mm) x 30 mm angiocath max flow rate = 105 ml / minute standard grey IV: 16 gauge (1.3 mm) x 30 mm angiocath max flow rate = 220 ml/min procedural IV: 18 gauge x 64 mm angiocath max flow rate = 85 ml/min medial (blue) & proximal (white) lumen of triple lumen catheter: 18 gauge x 190 / 180 mm max flow rate = 26 ml/min distal (brown) lumen of triple lumen catheter: 16 gauge x 200 mm max flow rate = 52 ml/min cordis / introducer: 8.5 french (2.8 mm) x 100 mm max flow rate = 126 ml / minute max flow rate with pressure bag @ 300 mmHg: 333 ml / minute   from ETM course large bore IV access showdown      

  blood draws and peripheral lines if necessary distal to a fistula, preferably on hand. from “I am not aware of any studies dealing with this issue. With respect to the extremity with a functioning access, the general recommended practice by Fistula First is that blood draws should be done in the non-access hand, to preserve veins that may be needed for future access. The next place to consider would be the access extremity hand, or possibly higher but below the access, depending on the circumstances.”