Superficial Cervical Plexus Block POD

That’s right. Time to talk about my favorite nerve block.

The SCPB

This block is 

quick

and

easy

.

It makes

IJ central lines

painless procedures

.

It also provides excellent analgesia for

clavicle fractures

,

ear lobe lacerations

,

blind subclavian lines

, or

anything within this quadrilateral

:

How to do it

Find the

posterior aspect of the sternocleidomastoid (SCM) muscle

.

Position the probe half way down the SCM as you measure it from mastoid process to clavicle.

About at the level of the superior aspect of the thyroid cartilage, also about where the EJ crosses over the sternocleidomastoid.

The fascial plane under the posterior aspect of the sternocleidomastoid muscle is your target.

Like other

plane blocks

 you are not targeting any one nerve in particular. By infiltrating this tissue plane, you get the superficial plexus as it peeks out from behind the SCM at this level:

Inject 5-10 cc of local anesthetic.

Ensure it is spreading in the plane like this.

Safety:

• As with all ultrasound guided nerve blocks, visualize your needle tip always, especially prior to injection.

• When you begin injecting, inject one mL only to ensure you see it spreading in the fascial plane. Then inject the rest.

• Withdraw before you inject if there is even a slight possibility you are close to a vessel

• Throw some color on your site to ensure you identify any vessels.

• In general this is a very well tolerated and forgiving block.

• The incidence of phrenic nerve involvement is extremely low with SCPB, far lower than with the interscalene block. Phrenic nerve involvement will be avoided if ensure you don’t go too deep - a few cm, or about half way down the deep edge of the SCM. Going deeper than this results in a deep cervical plexus block which will result in some motor and sensory blockade of the arm.

• Horner’s syndrome is a rare and self-limiting complication.

• The amount of local anesthetic used in this block is nowhere near close to toxic levels, so local anesthetic systemic toxicity will not occur as long as you manage to avoid the IJ and carotid.

Tips and troubleshooting

• For a central line, you can set up, gown, drape, and set up your ultrasound like usual, then use the 5 cc lidocaine which come in the central line kit for your block. Place the block first, then flush your line/lay out your equipment, and your patient will likely be completely numb by the time you’re ready to start your line placement.

• The other option is to place your block while you’re doing your pre-scan. This way you can use 5-10 cc, but you have to get it out of the Pyxis. Just clean the probe and the skin with a chlorhexidine swab and use sterile gel.

• If it’s your first time doing a block, consider doing it as a 2 person block. Use some IV extender tubing and have another provider operate the syringe for you. I like slightly longer tubing than typical IV tubing, e.g. the one below. At Maimo, you can find it in the stock room between North and South sides, top shelf straight ahead when you first walk in.

• Can't visualize your needle? Make sure your ultrasound probe is directly above it and in-line with it. Next, make sure it is as close to parallel to the surface of the probe/perpendicular to the ultrasound beams as possible. If you are approaching a 45 degree angle, your needle will be close to invisible. At close to a 0 degree angle, it will shine like a laser beam.

• You can use the 27 gauge needles to make it more comfortable but they are a little harder to see.

Further reading and references:

http://highlandultrasound.com/superficial-cervical-plexus-block/

 - Highland crushes nerve block education with their website and their SCPB page is no exception

https://www.ultrasoundpodcast.com/2015/03/superficial-cervical-plexus-block-with-bedsidesono-trust-us-this-is-really-awesome-foamed/

 - Mike and Matt of ultrasound podcast also did an amazing episode on this where many of the images in this tutorial are from

https://www.nysora.com/cervical-plexus-block

 -

Another good resource

Cordis Placement POD

Today’s Pearl of the Day is onCordis Placement! This topic is geared more toward our interns and second-years who have less experience in big trauma (have not yet rotated at Shock).

The

cordis is the preferred central line in trauma

, unstable GI bleeds, ruptured AAAs, or any other situation in which the necessity for rapid transfusion of blood products is anticipated. It is a short, wide, single-lumen central venous catheter that is perfect for rapid large-volume infusions.

The kit looks like this.

(The kit in the picture above also has a sterile sleeve for transvenous pacer placement, but that plays no role in cordis placement for resuscitation).

Here it is with all the components taken out, in order of use.

Note that when you first open the kit, the dilator sits BACKWARDS in the cordis catheter.

So the first step in setting up for this line is to take the dilator out of the front end of the cordis and place it in the back end of the cordis so it looks like this.

Flush the line (unless you need to draw blood off of it immediately) and lock it so it doesn’t bleed everywhere.

The rest of cordis placement is fairly straightforward.

Cordis placement: wire in, dilator-cordis in, wire and dilator out (while cordis catheter stays in).

Contrast that with

triple lumen catheter placement: wire in, dilator in, dilator out, triple lumen catheter in, wire out (while triple lumen catheter stays in).

For a more detailed explanation of cordis placement, READ ON!

By this point the patient has already been prepped/draped/anesthetized (if time permits).

The next step is to 

get your wire into the vessel

. To achieve this you can either use the wire-through-needle technique or wire-through-catheter technique. For a review of the wire through catheter technique, please see Dr. Strayer’s video on this topic: 

https://vimeo.com/133254469

I will focus on the wire through needle technique in this guide.. Note that this kit has a special

blue syringe: the introducer syringe.

 It has a hole in the back of the plunger that allows you to advance the needle directly through the syringe and out the needle. Using this feature allows you to skip the step of taking the syringe off the needle which can lead to the needle slipping out of the vessel.

If using ultrasound, note depth of vessel, position in center of ultrasound screen, visualize vessel, and advance needle tip directly into the center of the vessel (see my PIV POD email/Maimo Blog post 

http://mmcedrco.w02.wh-2.com/EMBlog/2018/08/23/

 for description of this technique).

If using landmarks (this guide will focus on the femoral vein site), place a thumb on the pubic symphysis and index finger on ASIS. The line between them is the inguinal ligament. Half-way between them is the femoral artery and 1cm more medial is the femoral vein. 

If you can’t remember which side the vein is on, remember “

venous is toward the penis

”. The

puncture site should be 1-2cm distal to the inguinal ligament

.

 If the artery is palpable, enter 1cm medial to it. If it isn’t easily palpable, enter just above the webspace between your thumb and index finger as they are positioned on pubic symphysis and ASIS respectively.

Always aspirate the plunger while you advance.

Once you get flash, keep needle/syringe perfectly still in non-dominant hand braced on patient. Check once more that blood can be aspirated, then reach for wire with your dominant hand;

advance wire through syringe

(assuming you’re using the blue introducer syringe). It should advance smoothly. If it doesn’t, take out the wire, check that blood is still easily aspirated, reposition or drop your angle as needed and try to advance wire again.

Wire is now in place.

Needle/syringe are removed

over the wire. Make a 

skin-nick with the scalpel

in the direction of the wire.

Advance the dilator-cordis-unit over the wire

, stabilizing the wire from behind the dilator-cordis with your non-dominant hand and advancing the dilator-cordis with your dominant hand.

Advance sequentially with small twisting motions

 always

gripping the cordis close to the skin

, until it is “hubbed” (cannot advance any further). 

Wire comes out, then dilator comes out.

(Or wire and dilator can come out together if you can grab them both comfortably). Flush your line, suture in place, cover with sterile dressing kit, and you’re done.

Image credit:

Brown EM Educational Blog Website

(

http://blogs.brown.edu/emergency-medicine-residency/the-central-line-part-2-technique-procedural-steps/)

Slideshare.net

Google image search

Visualize the Vessel: Jonas Pologe's Guide to US-Guided PIV Placement

Ultrasound-Guided PIV: Tricks of the Trade

That’s right, time to talk about one of my favorite topics ever: the ultrasound-guided PIV!

These are tricks of the trade that I have picked up from our amazing ultrasound faculty at Maimonides as well as concepts I have learned based on trial and error. I hope this guide provides some short-cuts to ultrasound-guided PIV expertise to newer trainees!

Procedure:

Scan the area with a tourniquet up to identify your best candidate vein. Look for the largest, most superficial, and most distal. It should ideally be greater than 3mm in diameter.

Visualize the trajectory of your vessel in both short axis and long axis.

Probe marker should be to YOUR left (the same side as the “Z” indicator at the top of the screen). That way when you move your needle left or right, it will go the same direction on the screen.

As you scan, note nerves and arteries which must be avoided.

The patient/extremity should be positioned such that the vessel is straight, and the probe as upright as possible on the patient’s arm.

Prep with chlorhexidine, prep the probe as well or cover the probe with a tegaderm, use sterile gel (“surgilube”).

Get your angiocath ready. Your go-to is a long 20 gauge. If it’s superficial and big and you are already confident in your PIV skills, you may consider placing a short 18, especially if needed for a CT angio. We don’t stock long 18s at this time but may stock them again in the future; these were an excellent option for larger but deeper vessels.

Find the vessel again in short axis at the point you have chosen to cannulate.

Press the Bx button to drop a guide line down the center of your screen. Position the vessel right in the center of that line.

This center line corresponds to the center of the probe:

The “0” on the probe with no notch on it is the center of the probe.

Note how deep the vessel is by looking at the hash marks at the R side of the screen. My vessel above is  about 0.75 cm down.

Now keep the probe still and look back at the patient’s arm.

Y

ou know exactly where the vessel is. Right under the center of your probe. You know its trajectory as well. VISUALIZE IT COURSING UNDER THE SKIN. That’s where your angiocath will go.

Now you are ready to enter the skin with your angiocath. Glance up at the screen one more time to make sure your vessel is still perfectly centered on your guide line. Look down at the arm and visualize the vessel again. Enter the skin a little ways back from your probe at a 30-45 degree angle. You know how long your angiocath since you’re looking at it and exactly where the vessel is since you are visualizing it. Using this information,

advance the needle with the aim of positioning your needle tip just over the vessel

, right at the vessel wall. As you do this,

look back up at the screen and you should see your needle tip coming into view

.

Confirm that you’re really seeing the needle tip

: Move the probe back (away from the direction of your needle) and watch the needle tip disappear; move it back toward the needle and watch it come into view again. Do this whenever you have any doubt that you’re actually looking at the tip.

Adjust left/right as needed so that your needle tip is perfectly above the vessel.

Enter the vessel by advancing downward a millimeter.

Sometimes a tiny “jab” will help get through the vessel wall.

Confirm that you’re looking at needle tip again.

You may have flash at this point but don’t look for it; it does not matter.

Drop the angle of your needle at this poin

t. The patient should be positioned so you can effectively drop the angle (arm should be straight if using AC fossa).

Then

advance the probe and needle sequentially millimeter by millimeter

: Advance the probe (needle disappears on the screen), advance the needle (needle tip reappears on the screen), advance the probe again (needle disappears on the screen), advance the needle again (needle tip reappears on the screen), etc.

The needle tip should be centered in the vessel prior to each advancement.

This is demonstrated beautifully by Dr. Cameron Kyle-Sidell in this 4-minute video.

https://emin5.com/2016/04/24/ultrasound-guided-iv-placement/

Once you have “walked” the needle tip into the vessel 5mm or more, keep the needle perfectly still, take the probe off the patient and put it down. Now with your non-dominant hand free, reach over and gently advance the angiocath over the needle while keeping the needle still with your dominant hand. It should advance smoothly.

————

A few last teaching points:

• Practice this skill on a model whenever you have a chance.

• Use the trick of dropping the Bx line, noting depth, and visualizing the vessel under the skin before starting a central line; if you are good at it with PIVs, you will find this part of central line placement extremely easy.

• Needle tip visualization is more difficult with deeper vessels and at steeper needle angles.

• If you are more than 1cm deep and have lost your needle tip, you may find it by switching to long axis

• Practice the microskill of “twisting” on a vessel in order to convert your short axis to a long axis view; practice this on your own radial artery as often as possible until it becomes second nature.

• You can do the entire procedure in long axis. This is a very powerful technique, especially for deeper vessels, but is technically more challenging and requires more practice.

• Use regular 22-gauge angiocaths with the “hockey stick” probe for babies and toddlers. If you are comfortable with this by the time you rotate on PICU, they will love you forever.

• An US-guided a-line is essentially the same procedure as an US-guided PIV.

Jonas Pologe, PGY3, Emergency Medicine, Maimonides Medical Center