About Mike Olshansky, DO, RN

Emergency Medicine Resident
Staten Island University Hospital
Northwell Health

Trick of the Trade: Ultrarapid adenosine push for SVT with a pressure bag

With some things in life, speed is everything. Adenosine is one of those things. With an ultrafast half-life estimated to be between 0.6 to 10 seconds [1], parenterally administered adenosine needs to reach the cells of the AV-node and cardiac pacemaker cells in an expedited fashion to facilitate the termination of supraventricular tachycardias (SVTs).

Known Techniques of Adenosine Administration

Currently, there are 2-syringe and 1-syringe methods that are widely accepted for the administration of adenosine. Recent data suggests that they are non-inferior to each other [2].

Classic 2-syringe method: Benefit = undiluted adenosine to the heart; Limitation = limited by the syringe flush volume [3]

1-syringe method: Benefit = large volume; Limitation = dilution of adenosine with IV fluid. Read more about the single syringe trick of the trade.

Trick of the Trade: Pressure bag setup

We propose administering undiluted adenosine in an ultra-rapid fashion via an in-line, primed saline tubing with a pressure bag setup.

adenosine iv tubing in y-injection site port

The unique aspect of the trick is to incorporate a high-pressure, unidirectional IV fluid administration system. It is similar to the 2-syringe system except that the flush syringe is replaced with high-pressure IV fluids.

How to set-up

Setup a pressure bag with a primed saline line in the standard fashion.
Close the roller clamp so that no IV fluid is flowing through the tubing.
Attach the IV line to the patient’s angiocatheter.
Attach a syringe with undiluted adenosine to the Y-site port as close to the patient’s IV as possible.
Open the roller clamp to start the high-pressure IV fluid administration.
Rapidly push the adenosine into the tubing.

Video demonstration

In this video, adenosine is the colored fluid for demonstration purposes. Notice how quickly the adenosine reaches the patient.

References

Parker RB, McCollam PL. Adenosine in the episodic treatment of paroxysmal supraventricular tachycardia. Clin Pharm. 1990 Apr;9(4):261-71. PMID: 2184971.
Miyawaki IA, Gomes C, Caporal S Moreira V, et al. The Single-Syringe Versus the Double-Syringe Techniques of Adenosine Administration for Supraventricular Tachycardia: A Systematic Review and Meta-Analysis. Am J Cardiovasc Drugs. 2023;23(4):341-353. doi:10.1007/s40256-023-00581-w. PMID 37162718
Kotruchin P, Chaiyakhan I, Kamonsri P, et al. Abstract 10470: Comparison between the double-syringe technique and the single-syringe diluted with normal saline technique of adenosine for a termination of supraventricular tachycardia: A pilot, randomized, single-blind controlled trial (DO-single trial). Circulation. 2021;144(Suppl_1). doi:10.1161/circ.144.suppl_1.10470

By Mike Olshansky, DO, RN|2024-06-19T23:51:46-07:00Jun 24, 2024|Cardiovascular, Tox & Medications, Tricks of the Trade|

Trick of the Trade: Gel-free ultrasound-guided peripheral IV technique

Ever finally step away from a busy resuscitation and someone stops you for peripheral IV access? You set up everything, have the patient positioned, and then notice there is no sterile ultrasound gel. No gel? No problem. The trick is to eliminate anything of poor acoustic impedance between the ultrasound probe and the patient’s skin.

Trick of the Trade

1. Apply a transparent adhesive dressing with a thin alcohol layer on the probe

Instead of using gel, we squeeze alcohol pads to create a thin alcohol layer and place a transparent adhesive cover, such as Tegaderm ©. The thin alcohol layer serves to eliminate any air bubbles under the adhesive cover as well as minimizes residual adhesive material sticking to the probe when removing the cover. The adhesive cover itself serves as a sterile barrier and a slick surface to improve probe maneuverability. Note that some ultrasound manufacturers do not recommend the use of isopropyl alcohol on their transducers. Therefore check your specific ultrasound’s recommendations before trying [1, 2].

2. Use sterile saline instead of gel on the patient’s skin

Squirt normal saline flush on the patient’s skin to create a coupling medium between the probe and the patient.

Why it works:

Ultrasound procedures use a range of frequencies (1.5-20 MHz) to visualize internal structures and require a medium to replace air, which has a poor acoustic impedance for the ultrasound waves [3]. Acoustic impedance is defined as the resistance of the propagation of ultrasound waves through tissues and is the product of the density and speed of sound in the tissue [4]. Ultrasound gel has an acoustic impedance that is similar to soft tissue and is therefore considered the ideal medium [3]. Because most soft tissue is comprised of water, the acoustic impedance of water, and therefore 0.9% saline, is actually pretty similar [5], as demonstrated by water bath techniques for ultrasounding distal extremity injuries [6].

We find great visual clarity for performing ultrasound-guided peripheral IVs using this trick, as shown in Figure 1.

Peripheral IV ultrasound screen without gel

Figure 1: Peripheral IV ultrasound using alcohol under transparent film dressing and topical saline flush – all without ultrasound gel

Read other Tricks of the Trade articles.

References

Cleaning and Disinfecting FUJIFILM SonoSite Products User Guide [PDF]. Sonosite. 2015. Accessed April 5, 2023.
Disinfectants and Cleaning Solutions for Ultrasound Systems and Transducers [PDF]. Philips. 2021. Accessed April 5, 2023
Afzal S, Zahid M, Rehan ZA, et al. Preparation and Evaluation of Polymer-Based Ultrasound Gel and Its Application in Ultrasonography. Gels. 2022 Jan 6;8(1):42. doi: 10.3390/gels8010042. PMID: 35049577; PMCID: PMC8774352
Suzuko S, Peter G, Philipp L. 20 – Local Anesthetics, Ed(s): Hugh C. Hemmings, Talmage D. Egan, Pharmacology and Physiology for Anesthesia (Second Edition), Elsevier, 2019, Pages 390-411, ISBN 9780323481106. DOI: 10.1016/B978-0-323-48110-6.00020-X
R. Alkins, K. Hynynen, 10.08 – Ultrasound Therapy, Editor(s): Anders Brahme, Comprehensive Biomedical Physics, Elsevier, 2014, Pages 153-168, ISBN 9780444536334. DOI 10.1016/B978-0-444-53632-7.01010-8
LeDonne S, Sengupta D. US Probe: Ultrasound Water Bath for Distal Extremity Evaluation. Alerhand S, Singh M, editors. emDOCs.net – Emergency Medicine Education. 2017.

By Mike Olshansky, DO, RN|2023-04-06T20:53:38-07:00Apr 12, 2023|Radiology, Tricks of the Trade, Ultrasound|