Category: Trauma Resuscitation

Large bore IV access showdown – Round 2

We got a lot of questions after round 1 of the large bore IV access showdown, mainly about the effect of points of narrowing that may be introduced to your fluid administration lines.

So we set up round 2, testing the effect of a fluid warmer, an IV bung and a 3-way tap on flow rates through an 8.5Fr RIC line attached to a high pressure rapid infuser system.

We also dismantle an IV bung to see just why they slow flow so much!

Check out the video to see the results.

And here’s a summary of the results:

Posted in Circulation, Procedures, Trauma Education, Trauma Resuscitation, Vascular accessLeave a Comment

ETM Podcast Episode 10 – Bruce Paix & Andrew Perry – Haemorrhage control in trauma

In this episode Andrew Perry interviews Bruce Paix, a very experienced pre-hospital/retrieval (and military) Anaesthetist and trauma expert about haemorrhage control in trauma.

This is a great episode with some real pearls. Bruce challenges the traditional teaching in trauma by asking us to not be afraid of the hypotensive trauma patient, but rather to accept it as part of our adaptive response to controlling our own bleeding and rather than calling it “permissive hypotension” he introduces the concept of “therapeutic hypotension”. He also emphasises that the volume or choice of fluid in trauma is far less important than stopping the bleeding. Other topics covered include the utility of end-tidal carbon dioxide monitoring as a marker of cardiac output, there’s a brief discussion of tourniquets (with more on this topic coming soon) and more!

Shout out to SAAS MedSTAR (the South Australian Pre-hospital and Retrieval Service) for granting permission for us to use this interview. Thanks!

Posted in Haemorrhage control, Podcast, Trauma ResuscitationLeave a Comment

Large Bore IV Access Showdown: Do you know which IV cannula can deliver fluid to your patient the fastest?

For decades now we’ve all been reciting the mantra that any sick or shocked patient needs:

“2 large bore IVs”

We’ve also all been taught that “short and thick does the trick” due to Poiseuille’s Law which states that flow is directly proportional to the fourth power of the radius, and inversely proportional to the length:

But despite our best efforts we couldn’t find a direct comparison of the various types of IV cannulas and catheters we used at work to see which one is actually best. We had unanswered questions that needed answers.

Which IV cannula/catheter delivers IV fluid the fastest?
How much faster is a 14G compared to a 16G, 18G or 20G?
Is a standard 14G faster than a RIC line or sheath introducer?
And just how much slower is a central line at delivering fluid?

Behold, the Large Bore IV Access Showdown. We’ve hooked up all of the major types of IV lines you’re likely to find in an average Australian ED to a rapid infusor device, and timed how long it took to pump through a litre of saline.

So which line was best? You’ll have to watch the video and find out!
(If you can’t stand the wait, skip ahead to the results at the 10:40 mark)

So the 8.5Fr RIC line was the winner!

Here’s our video on how to insert a RIC line

Here’s our rather unscientific, but hopefully visually useful comparison of the relative speeds at which fluid can be pumped through the different lines in our test:

Click to enlarge

And here’s our table of results:

Please feel free to download, share, embed, or otherwise distribute the video and results. And feel free to run your own trials and let us know if they’re similar or different!

For more information on the various types of large bore IV access check out our post on large bore vascular access devices. The astute will have noticed that we didn’t use a MAC-line (multi-lumen access catheter) in this test. This was because we don’t stock them in the ED we did the test in, and they are rarely (if ever) found in your average Australian ED, however most if not all of the other lines are.

This video and post were made for our new site EDProcedures so please head over there and check out our ED Procedures Course.

Hey, are you interested in accessing more online learning from ETM? Then head over to ETM Online and check out our new online Toxicology Course!

Posted in Circulation, Trauma Education, Trauma Resuscitation, Vascular access2 Comments

Large bore vascular access devices

There are several large bore vascular access devices available for rapid fluid and blood administration in trauma and resuscitation settings, and depending on which country you are in, and where you work, these devices may be referred to by different names.

In this post we’ll take a look at some of the different devices, what they are used for, and some practical tips if you decide to put one in.

DISCLAIMER: I have absolutely no financial or other interest in any of the brands or products mentioned in this post.

COPYRIGHT NOTICE: I have used several proprietary images in this post, and have acknowledged the source where possible. If you are the copyright owner of any of these images and would like them removed, please contact me here.

1) Sheath introducers:

Commonly referred to as:

Cordis
Swann sheath
Angiography sheath

Sheath introducers are long, very wide bore, single lumen catheters with a wide plastic hub on the proximal end, which has a central smaller hole (one-way-valved to prevent back-flow of blood), through which various other vascular catheters can be inserted, including triple-lumen central lines, Swann-Ganz catheters (hence the name “Swann sheath”), temporary external pacing wires and coronary angiography catheters.

They act as a “sheath” around these other catheters, providing a clean path and protected portal for these catheters to enter a vessel, whilst allowing simultaneous administration of fluid via the side-port or side-catheter, which runs perpendicular to the sheath, and has standard luer-lock connections to which IV giving sets can be connected. (Giving sets cannot be connected to the main sheath hub).

During procedures like coronary angiography, many angiography and stenting catheters are inserted and withdrawn through the sheath. During Swann Ganz catheter insertion it is sometimes necessary to move the catheter in or out to position it correctly. Using a sheath prevents multiple punctures of the skin, and it also prevents skin bacteria being carried into the vessel as long catheters are advanced and withdrawn.

In ED resuscitation settings, sheath introducers can be used alone for rapid fluid administration. IV fluid can only be administered via the side port tubing via a luer lock connection. Fluid cannot be administered via the main hub.

Brands:

Common brands of sheath introducer include Cordis, Arrow and Oscor. It seems our American colleagues have appropriated the name “Cordis” to refer to any sheath introducer. In Australia, many people refer to them as “Swann sheaths” (as they are used for Swann-Ganz or Pulmonary Artery catheters). These terms all refer to the same device!

Sizes:

Depending on the brand, these sheaths come in multiple diameters and lengths, ranging from 4Fr right up to the vein-busting 11Fr (i.e. very large!), and sheath lengths from from 5.5cm to 23cm.

A mid-range size of 8Fr would suffice in trauma resuscitation.

It is difficult to find documentation of the diameter of the side port tubing, or the connection point where the tubing joins the hub, and flow rates are not published. One would assume that the internal diameter of the side port is the same as the sheath, and that no narrowing would occur where the side port tubing joins the hub, but this is not clear.

Of some concern are these studies from the 1980’s:

Increasing the Functional Gauge of the Side Port of Large Catheter Sheath Introducers

Large Catheter Sheath Introducers and Their Side Port Functional Gauge

These articles look into flow rates through the side ports of sheaths. Whilst one would hope the designs have improved in the last 30 years, the article raises the issue that the point of connection of the side port tubing to the hub may be a point of narrowing, and therefore reduction in flow rate.

Insertion sites:

Due to their large size, sheath introducers should only be inserted into compressible, large veins (as they leave a large hole when removed that will require external compression to achieve post-removal haemostasis). These include:

External jugular vein
Internal jugular vein
Femoral vein

During angiography procedures, these may be inserted into the radial or femoral arteries, however this is not done in the Emergency Department!

Insertion technique:

Seldinger technique, with the dilator pre-loaded inside the sheath prior to starting, which allows for smooth insertion of the dilator-sheath complex in one movement, followed by removal of the wire and dilator.

Here’s Scott Weingart from EMCrit showing how to insert a “Cordis” (although it’s an Arrow branded line!)

UPDATE: Looks like Scott has deleted this video. D’oh!

Pros:

Very large access with very high flow rates possible

Cons:

It is actually very hard/impossible to find accurate product information on the actual diameter of the side-port tubing, and flow rates achievable through these devices
Flow is reduced if another catheter is placed through the hub into the sheath (e.g. a CVC or PA catheter)
Post removal complications:
- Bleeding
- Air embolism
Inadvertent large-bore arterial puncture (although these are inserted into arteries for angiographic procedures)

Complications:

As with any central access device, the potential complications include:

vessel wall perforation
pleural and mediastinal injuries
air embolism
sheath embolism
thoracic duct laceration
bacteremia/septicemia
thrombosis
inadvertent arterial puncture
nerve damage
hematoma
hemorrhage
dysrhythmias
occlusion

Air embolism

This is a real risk with these catheters. Air can enter the central haemostasis valve while in-situ, or the puncture site post removal. This can be avoided by keeping the haemostasis valve/hub covered with an “obturator” (the blue twist-lock cap), a sterile gloved finger, or by inserting another catheter (e.g. Swann/CVC). Also having the patient head-down during insertion/removal via jugular veins, or supine during insertion/removal via femoral vein will minimse the risk. An airtight/occlusive dressing should be applied for 24-72 hours post removal, as air can enter until the hole in the vein is sealed.

Arrow Haemostasis Valve Short Obturator

Image Source

More information on air embolism here and here.

What if I accidentally put one into an artery?

If you accidentally insert a sheath introducer into an artery, don’t panic, as this is routinely done during coronary angiography procedures (via the femoral or radial artery), however upon removal they require at least 20 minutes (and often longer) of direct pressure, sometimes using a “femostop” direct femoral artery pressure device, and close monitoring for bleeding after this. This is not something you want to be doing during an ED/trauma resuscitation!

Mechanical femoral artery pressure devices:

Image source: 1, 2

2) Rapid Infuser Catheter (RIC) Exchange Sets

Commonly referred to as:

RIC set or RIC line

RIC lines are a superb invention, that allow for rapid upsizing of an IV as small as a 20G (pink) to a very large bore catheter, in a peripheral vein. The main advantages of RIC lines are:

- - Can be inserted in peripheral veins
  - Can “upsize” an existing IV cannula via seldinger technique using the wire in the kit
  - The kit only has 3 items: the RIC line/dilator, a wire, and a small scalpel, so there’s no rummaging around through a tray with lots of unnecessary pieces

Brands:

As far as I know, Arrow makes the only true RIC set

Image source: ETM Course Manual

Sizes:

The Arrow RIC sets come in:

7 Fr (internal diameter) x 2 inch (5.08cm)
8.5 Fr (internal diameter) x 2.5 inch (6.35cm)

The smallest IV that you can get the wire through is a 20G (pink).

Image source: ETM Course Manual

In shocked, peripherally shut down trauma patients, it is very hard to get 16G or 14G IV’s into these collapsed veins, but getting a 20G in is much easier. You can then insert the wire, take the 20G cannula out, and seldinger the RIC over the wire in about a minute.

Sites:

To insert a RIC, you ideally need at least 6-8cm of relatively straight peripheral vein

Common sites include:

- - Cubital fossa: cephalic or basilic vein
  - Cepahlic vein in forearm
  - Saphenous vein
  - External jugular vein

Image source: ETM Course Manual

The femoral vein is probably too deep, even in slim patients, for a RIC line. RIC’s are only 5-6cm long, so by the time you’ve gone through a couple of centimetres of subcutaneous fat and entered the femoral triangle, you’ll only have a couple of cm of catheter in the vein – very easy to dislodge. If you want femoral access, go for a sheath introducer or a MAC.

Hot Tip:

Avoid large bore/rapid infuser catheters in leg veins (e.g. saphenous or femoral) in major pelvic or abdominal injury.
All the infused blood will end up in the peritoneal/pelvic cavity and not in the heart/brain where you want it!

Insertion:

Here’s a video on how to insert a RIC line:

Pros:

- - 8.5Fr RIC likely has the fastest flow rates of available IV access devices
  - Relatively cheap compared to sheath/MAC sets
  - Easy to insert, only takes about a minute
  - Can upsize an existing cannula
  - Ultrasound not required

Cons:

- - Sterility can be an issue if upsizing an existing cannula or when inserting under duress in a resus
  - Too short for deeper/central veins

Update:

Check out our Large bore IV access device showdowns to see just how fast the flow rate through a RIC (and other commonly used devices) is!

Large bore IV access device showdown – Round 1

Large bore IV access device showdown – Round 2

3) Emergency Infusion Device

I haven’t seen one of these in use in an Australian ED, so won’t write a detailed comment, but thought I’d mention these for completeness.

They are a cross between a RIC line, and the single piece needle-catheter-sliding-wire arterial line kits, but are designed for venous access.

They comprise a small 20g needle, over which lies a dilator, over which lies the 6 or 8.5Fr catheter

Image source

Insertion is via the needle entering the vein, at which point a flashback should occur, the wire can then be advanced into the vein by sliding it down with the small proximal plastic tab. The dilator and catheter can then be fed along the wire.

I personally find the arterial line version of these very fidgety to put in. But some people love them. Have a look around your department and let me know if you have them, and what the pros and cons are!

Sizes:

6Fr x 1.5in (3.81cm)
8.5Fr x 3.5in (8.90cm)

4) Multi-Lumen Access Catheters

Commonly referred to as:

MAC line

The MAC (Multi-lumen Access Catheter) line is a (relatively, compared to a standard central line) short, 2-lumen line made by Arrow. Like the others it is inserted via seldinger technique. As it’s longer and much thicker than a RIC line, it should be inserted into a large vein.

Image source

It has a sheath introducer built in as well as a 9Fr and 12Ga lines. The main benefit of this line is the 9 Fr large lumen, which can be used as a rapid infusion device, while the 2nd 12Ga line can be used for other fluid and drug infusions, including any other incompatible fluids.

So it is essentially the same as a sheath introducer, with the 9Fr side port coming off at a more actute angle, (rather than perpendicular to the sheath, as the standard sheath introducer has) with an additional 12Ga line.

The advantage of having a sheath introducer built in is that a standard triple lumen central line (or the proprietary “MAC Companion single, double or triple lumen 7Fr catheter”) can be placed through the sheath hub, which can then allow for accurate CVP monitoring, and increases the total number of ports up to 5. This may sound excessive, but critically ill trauma patients, for example those with severe head injuries, may easily end up on 5 or more infusions in ICU. This makes the MAC a multi-purpose, resus and ICU line.

A MAC line with a triple lumen CVC through the sheath introducer
Image source

The tray for a MAC line – compared to a RIC line there’s a lot
Image source

Brands:

As far as I know, Arrow makes the only commercially available MAC line

Sizes:

The standard Arrow MAC line has 2 usable lumens: 9Fr Side port and a 12Ga line (the sheath introducer is not for fluid administration)

The main body of the catheter is 10cm long.

NB: Technically if you compare the sizes on a standard catheter sizing chart:

9 Fr = 3mm outer diameter

12Ga = 2.769mm outer diameter

i.e They are almost the same!

However once you get to the inside of the main catheter, things change:

Image source

This is a cross-section of a MAC line main catheter. It’s unclear what the flow dynamics are through the crescent-shaped 12Ga lumen.

Despite the similarities in the apparent side port external diameters, the flow rate through the 12Ga port is quoted at 11 litres per hour compared to 29+ litres per hour via the 9Fr port (this is for gravity flow rates).

And, just to confuse things, the actual diameter of the main catheter body is 14 Fr!

Image source

Sites:

External jugular
Internal Jugular
Subclavian*
Femoral

*Subclavian MAC lines – a cautionary note

Some Australian trauma centres use MAC lines via the subclavian route. This route is generally only preferred if the patient has a concurrent ipsilateral chest injury with an intercostal catheter already.

This is because if there is in inadvertent puncture of the pleura, or intercostal vessel injury during MAC insertion, the subsequent pneumothorax/haemothorax is “already treated”.

However there are other significant risks in placing a subclavian MAC line, mainly that they leave a large hole in non-compressible vessel when removed, which can bleed a lot, and act as a portal for an air embolus.

A recent case a colleague observed highlighted the dangers of subclavian MAC lines:

A man with a right sided chest injury (haemo-pneumothorax) had a right intercostal catheter inserted, and a small to moderate amount of blood drained. He then had a right subclavian MAC line inserted, with aspiration of blood, and a CVP trace was transduced. However the patient remained very unstable, and only partly responded to massive transfusion via the MAC line, whilst the amount of blood draining from the chest drain steadily increased. It was then found that the MAC line was in fact intra-pleural, not intravascular. The “CVP” trace was either correct and the catheter subsequently dislodged, or was in fact an unrecognised intra-pleural pressure trace. The massive transfusion was simply going into the pleural space, and out the chest drain.

These are not benign lines, and are best inserted by those experienced with large bore central venous access, ideally with ultrasound guidance.

So there you have it. A deep dive into the commonly used, very large bore vascular access devices used in trauma.

Do you have any pearls about big lines in trauma? Do you use any different types of lines? Leave a comment below.

Hey, are you interested in accessing more online learning from ETM? Then head over to ETM Online and check out our new online Toxicology Course!

Posted in Circulation, Trauma Procedures, Trauma Resuscitation, Vascular access3 Comments

ETM Radiology: That’s not a knife!

In true Aussie trauma style, we pay homage to Crocodile Dundee, with a case of penetrating chest injury. Can you troubleshoot the chest in this tricky case?

A 49 year old man presents after being stabbed multiple times in the left anterior chest.

Paramedics state that en-route he was tachycardic to 125 bpm, his oxygen saturations were dropping to 88% despite supplemental oxygen, he had absent breath sounds on the left, and they therefore decompressed his left chest with a pneumocath/pleurocath, placed in the left anterior 2nd intercostal space attached to a heimlich valve.

On arrival the patient was alert, GCS 15, with a persistent tachycardia and persistently low sats around 90-92% despite supplemental oxygen. He had 3 x 2cm stab wounds to his left anterior precordium, and the pneumocath was in situ.

The Police are in attendance and produce the weapon for inspection by the treating team. (iPhone used for size comparison)

[DDET What structures may be injured in stab wounds to the left anterior chest? Click for answer]

Stab wounds to the left anterior chest may cause:

Pneumothorax
Haemothorax: with bleeding from chest wall tissue or intercostal muscle, intercostal or internal mammary vessels, lung laceration, major vessel injury or cardiac injury
Cardiac injury with or without tamponade
Tracheo-bronchial injury

Depending on the length of the blade and angle of insertion, other structures that may be injured include:

Neck – airway, vessels & nerves
Thyroid (thymus in babies/kids)
Diaphragm (and sub-diaphragmatic organs)
Spine – it would have to be a very long knife!
Thoracic duct

[/DDET]

[DDET What rapid bedside investigations would you perform?(Click for answer)]
Chest x-ray
There is debate about the utility of chest x-ray in patients who will undergo a CT chest regardless of the x-ray findings, however it’s still recommended as a quick, low to no risk, non-invasive procedure, especially in penetrating chest trauma.

This is the patient’s first chest x-ray:

It shows an apparently inflated left lung (small residual apical pneumothorax) with a pneumocath in situ, and no haemothorax. The cardiac contour looks normal.
Do you notice anything else about this image?

Bedside ultrasound
E-FAST can detect pneumothorax, haemothorax and pericardial effusion/tamponade with greater sensitivity than chest x-ray.
However this is operator dependent and other factors such as obesity, subcutaneous emphysema and chest wall haemaotoma may hinder the views. In this case, there was poor views of the heart on bedside ultrasound. No massive pericardial effusion but we couldn’t exclude it.

[/DDET]

What happened next?
Given the obvious penetrating injuries, and pneumocath insertion, an intercostal catheter was inserted. Only 50 ml of blood drained on insertion.

[DDET Click to see the first post-chest drain x-ray]

Chest x-ray 2 - post ICC insertion — Chest x-ray 2 – post ICC insertion

It shows an apparently inflated lung, with a fairly well positioned chest tube (1 or 2 rib spaces higher is ideal)

[/DDET]

So he should get better now, right?

The patient remained tachycardic, the sats hovered around 92-94% on oxygen, and his blood pressure remained around 100 systolic. Not the fantastic response to decompression/ICC insertion we were hoping for!

[DDET What could be going on in this patient’s chest to explain the lack of improvement post chest tube insertion?]

1) Occult injury
Lung or treacheo-bronchial injury +/- ongoing air leak/tension could explain the ongoing hypoxia and haemodynamic compromise, but the lung looks well inflated! Doesn’t it?

Haemorrhage could explain the haemodynamic compromise but not the low sats. There’s no gross haemothorax on the film and only 50ml of blood was drained from the chest drain.

Tamponade? Could be causing the signs we’re seeing, but he’s remarkably “stably unstable”. i.e. He’s not deteriorating. One would expect a patient who is tamponading from a hole in the heart to deteriorate in front of you, or at least be more unstable. This patient’s vitals are relatively static.

2) Chest tube:
Malposition
The chest tube may not be in the pleural space, but the drain was seen to swing & bubble on insertion.

Malfunction
The drain was checked and it is filled/setup correctly.
Could it be kinked or blocked with clot? Possibly, but this is very rare.
Could the connection between tube and drain be loose? This was checked and found to be well connected with no leak/entrainment of air.

[/DDET]

What happened next?

The patient was taken to CT, and this is his scan

[radiologystack cats=18]

It shows a well positioned intra-pleural chest tube, a small haemothorax, and a persistent pneumothorax. Look closely at the pneumocath. It’s intra-ulmonary (i.e. it’s in the lung), possibly with the tip in a bronchus. This has created a fistula between the patient’s airway and the outside of the chest, which has impaired lung re-expansion. This also raises the possibility of an air leak from lacerated lung, that is allowing air to enter the pleural space faster than the chest tube can withdraw it. Look closely at the base of the heart as well. There is no large pericardial effusion, but there is some blood sitting near the apex.

[DDET The the lab rings. Can you guess what the troponin was?]

28,000! Yep, and that’s the new high sensitivity troponin (with a bad STEMI usually peaking around 2,000-3,000). Not only does this guy have a likely broncho-atmospheric fistula from the pneumocath, and/or lacerated lung causing a persistent air leak, but his myocardium is injured as well.

[/DDET]

On return to the resus cubicle, the pneumocath was promptly removed, the first chest drain was placed on suction with no effect, and a second chest tube was inserted. He went to theatre shortly thereafter for a median sternotomy.

[DDET Here’s the chest x-ray post 2nd chest tube insertion]

After the 2nd tube was inserted, the sats started coming up, the pulse slowed a bit, and the Thoracics Team arrived to whisk him off to theatre.

[/DDET]

Injuries found at operation:

Lacerated lung from knife wounds – repaired

Hole in lung from pneumocath – repaired

Lacerated myocardium – heart chambers not penetrated – repaired

Lessons from this case:

1) Chest X-ray has limitations in trauma
Go back to the initial chest x-ray. What’s wrong with it? It’s supine. In fact all of them are. In pentrating chest trauma with a systolic BP > 90, don’t be afraid to sit the patient up for the chest x-ray. It may have shown the non-inflated lung, and moved the team to the 2nd chest tube more quickly. Supine chest x-rays can easily miss a pneumo or haemothorax. Ultrasound is better, however in this case, it didn’t help due to the overlying tissue damage, and subcutaneous emphysema.

For a great discussion on the utility of chest x-rays in trauma – head over to St Emlyn’s where Simon Carley does a great podcast, and engages in some lively debate in the comments section on ditching superfluous, low sensitivity, time-wasting procedures and processes in resus.

If you’re going to bother to get a chest x-ray in penetrating chest trauma, and the patient can tolerate sitting up without fainting from hypotension – sit them up!

2) A non-inflating lung with an adequately positioned chest tube means there’s an air leak

A broncho-pleural connection will allow air to continue to enter the pleural space, sometimes faster than a chest tube can get it out. The management for this is to apply wall suction to the drain (NOT the tube!), and if this doesn’t work, insert a 2nd chest drain. A broncho-atmospheric connection (eg from a pneumocath) means the inhaled air will bypass the pleural space, and the trapped pleural air won’t escape, rendering the pneumocath useless. If there is a hole in the chest wall that has not closed over you can get a broncho-atmospheric connection, however the pressures in the airway and atmosphere should be roughly the same, so you shouldn’t get tension. Without a broncho-pleural connection, a non-sealed chest wall hole will act as an open pneumothorax, and draw air from outside inwards during inspiration, (the “sucking chest wound”), and you may see bubbling from the wound on exhalation as some of the air in the pleural space is expelled. The treatment for this is either a 3-sided dressing (which are notoriously hard to get to work), or insert a chest tube elsewhere in the hemithorax (not in the hole) and repair/close/seal the sucking wound.

3) Knives are dangerous

As the London HEMS know all to well, with their case series of roadside thoracotomies for penetrating chest injury, knives vs chests all too often ends in tragedy. As demonstrated by the lack of utility of chest x-rays in this case, your threshold for getting a CT scan for anyone stabbed in the chest should be very low. Wound exploration of thick chest walls with intercostal muscles that close over the tract can be falsely reassuring. Patients can bleed and deteriorate slowly, so initially normal vital signs can be falsely reassuring. And as in this case, chest x-ray (even with an adequately positioned ICC) can fail to detect significant pneumothoraces.

4) Pneumocaths/pleurocaths don’t always work, and may cause problems

There are various commercially available pleural drainage kits used by ambulance and pre-hospital services. Most involve a seldinger type kit, usually fitted to a heimlich valve (a one way valve with a rubber sleeve inside a clear plastic chamber). Complications of pneumocaths/pleurocaths include:

Too shallow – failure to reach the pleural space – subcutaneous air may be aspirated giving a false positive result without treating the pneumothorax
Too deep – can penetrate the lung/other organs
They can get blocked with blood or kink – leads to re-accumulation of pneumothorax
Intercostal vessel injury – haemorrhange

In this case the intrapulmonary insertion rendered the pleurocath ineffective.

pleurocath heimlich

Posted in Trauma Radiology, Trauma Resuscitation, Uncategorized2 Comments

ETM Journal Club: Pressure, perfusion, and compartments

This is a review article (available free online over at The Journal of Trauma and Acute Care Surgery) that covers compartment syndrome by body region, reviewing the latest evidence and challenging some dogma related to this fascinating condition.

Ivatury RR. Pressure, perfusion, and compartments: Challenges for the acute care surgeon. J Trauma Acute Care Surg. 2014 Jun;76(6):1341-8

As the article is available free online, I won’t do a full analysis of it, but anyone who manages trauma, burns, or other critically ill patients should read this article as there’s some great learning points about compartment syndrome.

Take home messages:

Recent evidence suggests that the relationship between intracranial pressure (ICP), cerebral perfusion pressure (CPP), cerebral blood flow and the risk of death is not as simple as once postulated, and there are likely pathologic processes in the injured brain that do not directly involve increases in ICP and decreases in CPP.
Orbital compartment syndrome occurs in facial trauma, but may also occur in major burns patients who receive too much crystalloid fluid during resuscitation.
Post cardiac surgery (for example open heart surgery, or post repair of penetrating cardiac injury), too much intravenous fluid causes cardiac dilation, which causes raised intra-thoracic pressures if the chest is closed, resulting in impaired cardiac filling and hypotension. This may manifest intra-operatively during closure, or days later in ICU with increasing airway pressures and haemodynamic instability.
World Society of the Abdominal Compartment Syndrome (WSACS) have published clinical practice guidelines for the management of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS), available free open access at Intensive Care Medicine. The guidelines cover issues such as abdominal pressure monitoring, sedation and paralysis, role of renal replacement therapy, decompressive laparotomy, open abdomen management, negative pressure wound therapy and more. You can also download free algorithms on ACS assessment and management from WSACS.
Poly-compartment syndrome reflects the interplay between pressures in the intracranial, thoracic and abdominal compartments. Examples include increasing ventilator pressures to manage injured lungs which can increase intracranial pressure (negatively impacting on concurrent brain injury), and the relatively new technique of reducing intracranial pressure by opening the abdomen. (There is a great lecture by the pioneer of this technique, Thomas Scalea, over at EMCrit).
The classic clinical signs of compartment syndrome in the extremities are specific but not sensitive and the definitive way to diagnose it is with invasive compartment pressure monitoring. However the threshold pressure or exact indication for fasciotomy remains unclear! What is very clear is that delays to fasciotomy result in worse outcomes if the diagnosis is delayed or missed.
Newer techniques such as Near Infra-Red Spectroscopy and Raman Spectroscopy are showing promise in being able to diagnose extremity compartment syndrome, but are likely to only be available in tertiary centres.
There is an extensive discussion about compartment syndrome in the extremities in the article – well worth a read.

This is a succinct, up to date review that has some very salient learning points for anyone who manages critically ill or injured patients.

ETM Rating: Highly recommended

Posted in General Trauma, Trauma Education, Trauma Resuscitation, UncategorizedLeave a Comment

Thoracotomy Critique

Question:

[DDET What are the most feared procedures in Emergency Medicine? (Click for answer)]
1) Perimortem C-Section
This is actually the number 1 answer, a truly nerve-jangling experience for all involved, and sure to leave a deep mental impression. There are some great posts about this topic over at EMCrit, StEmlyns and Broome Docs that cover this topic, and I’d recommend you view all of them, twice…

2) Manual faecal disempaction
Isn’t this what medical students are for?

3) ED Thoracotomy
Like the peri-mortem C-section, this is a rarely encountered, invasive procedure that you may never need to do, but you must know how to, just in case, one day, you’re the one holding the Finochietto. Haven’t had to do one yet? Worried you’ll bugger it up when your turn comes? Then hopefully this post will help you overcome some of that fear.
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Read on as we watch others go elbows-deep in the thorax, in real-time, and critique their performance from the comfort of our armchairs, so that if and when we are faced with this situation, we remember how to do it right.

We’ll use the plus/delta method of critiquing, which is a great way to do succinct, rapid feedback on a scenario.

WARNING: All of the following videos contain graphic material, intended for medical professionals only.

VIDEO 1: “Slow is smooth, smooth is fast”

This is a classic “amateur thoracotomy”, video but it still contains useful learning points (and is one of my all time favourite movie scenes…)

httpv://www.youtube.com/watch?v=KBIdcUxdgo0

Click on the Plus/Delta below for the feedback/critique.

[DDET Plus]

“Slow is smooth, and smooth is fast”. The slow, steady hand movement and calm concentration meet the Scott Weingart recommended mode for performing any difficult procedure: “Slow is smooth, and smooth is fast” is a mantra from Scott’s Crack to Cure talk that I use all the time, at home and at work. What you think is slow in these settings, is actually very fast due to the time distorting effects of adrenaline. If you rush you will cut yourself or your assistant, or make a big mistake.
Complete evacuation of the pericardium. In real-life, you don’t want to remove the heart entirely to inspect it for injuries, but it is important to remember that the pericardium may appear externally normal despite the presence of tamponade, so if you are opening the chest, you are opening the pericardium and delivering the heart.

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[DDET Delta]

Ensure patient meets indications for thoracotomy. These are still debated, but my indications are:
- Cardiac tamponade in haemodynamically distressed patient with blunt or penetrating truncal trauma
- Defined as SBP < 70mmHg (which is the pressure needed for coronary perfusion in diastole) despite pleural decompression & IV fluid replacement
- Traumatic cardiac arrest:
  - Blunt: Arrests in the ED/Dies in front of you
  - Penetrating: Arrested but has “signs of life”
    - Pupil reaction
    - Gag reflex
    - Electrical activity on monitor (includes PEA)
    - Cardiac motion on echo/ultrasound
Work on sterile technique. There’s not point getting an output back if the patient dies or has major complications from a wound infection. Pour the betadine on. Sterile gloves. Sterile tray of instruments.

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VIDEO 2: A “successful” thoracotomy

In this video you see a chest get cracked, with return of ROSC, which is technically a “success”, but there are many learning points here – the “Delta” section is longer than the “Plus”…

httpv://www.youtube.com/watch?v=8BlPxQI2C90

[DDET Plus]

Finichietto placed the correct way, handle DOWN. This means you can extend to a “clamshell” thoracotomy by extending the incision across to a right sided thoracotomy. NB To do this you need to cut through the sternum with a special device (options include a Lebsche knife/chisel, a Gigli saw, a pneumatic or battery powered sternal saw, or good ol’ trauma shears – see below). Clamshell is indicated if you find a cardiac injury, or the left thoracotomy is negative and you have large volume blood loss from the right chest ICC.
Right side of chest decompressed with ICC. This is a must. If you do a left thoracotomy, but don’t find tamponade, the cause of the arrest may be in the right chest. Decompress with finger then tube thoracostomy. Ideally this would have already been done, but of it hasn’t, you need to do it.

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[DDET Delta]

Where do we start? OK, not to be too critical, as stated this is in the top 3 most stressful things you can ever do in your career, and it’s easy when you’re not the one in the hot-seat, but there’s some important things that should not be replicated in this video.

Stop the CPR: I lost count how many times the guys with the knife/scissors nearly cut their own or someone else’s fingers off. Whilst it may theoretically give some small volume of cardiac output, if you think about the physiology here – ie heart can’t pump because it can’t fill, because the pericardium full of blood is squashing it – then CPR is useless, and very, very dangerous. It also makes the rib spreaders fall out at one point. Ideally you’ll have the chest open, and pericardium incised in under 2 minutes in a patient who is intubated and receiving 100% oxygen. The best thing you can do for their brain is open the chest, and it’s very hard to do this while it’s bouncing up and down.
Personal protective gear: This is a bloody, messy procedure with sharp things (including pointy fractured ribs) flying everywhere. Full length gown, with sterile double-gloves pulled over the cuffs, with eye protection and a mask is the minimum.
Right equipment. At the 22-second mark you hear someone say “he needs a bigger knife”. If you see how it’s done in videos 3 and 4, you’ll see a non-CPR chest with a large scalpel, and it doesn’t take that many cuts to get where you want.
Indication: Blunt trauma with pre-hospital arrest – prognosis close enough to zero to not warrant the risk. Remember, indication for thoracotomy in blunt trauma = DIES IN FRONT OF YOU, IN THE ED.

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Video 3: In contrast…

Contrast this with video 2, in particular the general atmosphere in the room, and the technique of the operator.

[DDET Plus]

Setup: Wide application of antiseptic (“baptised with betadine”), giving a wide sterile field, good lighting, assistant holding retractor and a nice big scalpel.
Technique: 4 cuts and he’s into the chest. A quick run up and down with the scissors and the rib spreader’s in. From scalpel touching skin to heart being exposed is under a minute and a half. Slick.

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[DDET Delta]

Not much to criticise here. Lack of face shield.
Hard to see how the pericardium is opened, however it’s apparently not a big deal as they get ROSC.

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Video 4: Cadaveric demonstration video

The producers of the following video have very generously given us permission to use their videos in our course manual, so if you sign up to the ETM Course, you’ll get this video and some other procedure videos from the same team that you can watch, in your manual, in iBook format!

httpv://www.youtube.com/watch?v=A57ZB_J4FuY

[DDET Plus]

Good scalpel technique – long, slow, deliberate but firm strokes, with assistant’s hand well out the way and providing retraction of breast tissue.
Identifies phrenic nerve before incising the pericardium. They use the word “above” in the commentary, but I think they mean above as in “toward the ceiling” (which is medial), rather than above meaning superior. If you go as far toward the sternum as you can reach to make the incision, you’ll avoid the phrenic nerve.

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[DDET Delta]

Could possibly have extended the incision in the intercostals a bit more posteriorly, as it seems he has trouble getting the rib spreaders in.

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Conclusion

So there you have it, an armchair critique of a few ED resuscitative thoracotomies. I think it’s really important to use this video critique method, and to watch these videos several times, visualising how you’d perform this procedure. As you can see, it doesn’t need to be a situation defined by panic or fear. Knowing who to do it on, how to do it methodically and calmly, and what to do once you’re in there are key to mastering this rarely performed procedure.

If you want more practical tips on thoracotomy in the ED, I can’t recommend Scott Weingart’s Crack to Cure talk enough. It’s the definitive talk on ED thoracotomy, and is full of practical tips and tricks.

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