Category Archives: Procedures

Podcasts – needle versus knife

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Still listening to the Backstreet Boys on the way to work? Clearly urgent intervention is required.

Here are some excellent podcasts, with blog pages including discussion, videos, and references:

Needle versus knife I – discussion between Minh Le Cong (prehospitalmed.com) and Scott Weingart (emcrit.org) about interventions for can’t intubate/can’t ventilate

“One of the best things Minh expressed is the need to say OUT LOUD: “This is a can’t intubate/can’t oxygenate situation.” Saying it out loud lets everyone in the room know, there will be no more screwing around with attempts at direct laryngoscopy.”

Podcast is here

Needle versus knife II – chest decompression – from Scott Weingart

“Anterior approach is not where you think it is”

“ED Docs got it wrong a lot!”

Podcast is here

Is there more to meets the eye to pre-hospital intubation than just a tube?

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In a recent review of the literature about pre-hospital intubation in traumatic brain injury (TBI) and the potential impact of hyperventilation, Gaither et al. explore the potential confounders for outcomes in previous studies. 

The authors provide a nice overview about the “old school” rationale for hyperventilation in TBI and why it is unlikely a good idea!

Why hyperventilation thought to be beneficial in TBI: 1) decreases arterial PaCO2 with CNS vasoconstriction 2) decreased cerebral blood flow. Net result is improved cerebral perfusion pressure (CPP). However, hyperventilation after intubation may increase intrathoracic pressure, increase JVP and subsequently decrease CPP. Hypocarbia may also lead to free radical formation and cellular damage. So net result is PaCO2 of 25 isn’t a good idea! Probably best to target into something like 35.

The authors then outline the historical concerns about pre-hospital intubation (low success rates, long scene times and complications like hypoxia). However, they argue that perhaps its not the intubation itself that may confound these “worse” outcomes, but perhaps the greater potential for hyperventilation! And the detrimental effects may in fact occur post-intubation.

There’s some evidence that in pre-hospital settings where end-tidal CO2 is closely regulated (assuming high intubation success…which probably requires well-trained personnel) that patients do better if they’re intubated…just so long as we keep their ETCO2 under control! The following is a direct quote from the article:

“There is a strong possibility that the negative effects of intubation that have been identified in several clinical trials may be due to a paradox: intubation may protect the airway and prevent hypoxia, but it also makes it easier to inadvertently hyperventilate. Consequently, although intubation is intended to reduce secondary brain injury, it may enhance it if specific, intentional measures are not taken to ensure proper post intubation ventilation“

A nice conclusion is provide (which I fits well within the general tone of the article).

“When properly performed, intubation is effective for airway protection and ensures adequate oxygenation; it also makes hyperventilation (and associated negative outcomes) easier and more likely. Optimal outcomes require choosing the right patients, achieving the highest success rates through training, and avoiding hyperventilation after intubation in patients with traumatic brain injury”

This article makes a great case for well trained medical personnel who perform pre-hospital intubations and then provide the best post-intubation care possible.

Full text pdf is available here (secure area limited to ADHB staff only – ADHB has subscription access for staff to these journals through the Philson Library at the University of Auckland School Of Medicine)

Pre-hospital thoracotomy in the Journal of Trauma

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Recently Scott put up a post on this topic and given it’s infrequent occurrence, we don’t mean to spend lots of time but this editorial/article came up so I couldn’t resist mentioning it once more (plus, let’s be serious emergency thoracotomies are pretty awesome especially given they can be life-saving).

I’m not sure how I feel about the idea of pre-hospital thoracotomy (followed by helicopter transport), especially given the often dismal outcomes and the potential for considerable harm. Nevermind the fact that once you performed the procedure, you then have to pack up the patient who has an open chest and get them via helicopter to the ED (wow…).  I have to say I’m not particularly in favor of it, but willing to look at the evidence, which this article presents. The authors review the literature and summarize that among those with penetrating trauma (a key distinction), that there’s a survival rate of 11%. Looking at this superficially, that means that there’s a bunch of people that were actually dead who were subsequently saved. What we don’t know is much about the potential for harm (e.g needlestick injuries to healthcare provides, prolonged ICU stays without benefit). In summary, the authors cite the successes from London HEMS and they are clear supporters of this procedure but correctly address the minimal role in blunt trauma. Furthermore they suggest that additional research is needed…realistically, probably hard to gather much more than case series unfortunately. I won’t hold my breath for a large randomized trial in the New England Journal.

An editorial critique follows the article by Dr. Ken Mattox (the world renowed surgeon from Houston of permissive hypotension fame). In looking at both sides he uses the Altemeier axiom “sometimes a solution to a problem creates 4 times as many problems” and I think that definitely could be applied to this procedure. However, he doesn’t exclude the possibility that pre-hospital thoracotomies might have a role in the correct circumstances. He mentions the following overriding principles that would have to be applied

  • Protocol overseen by established trauma program and approved by IRB
  • Adequate training and appropriate instruments and equipment
  • Ability to have communication with the trauma center and trauma surgeon in case of any “surprises”
  • All cases must be carefully reviewed by the trauma program for quality assurance

So while it remains controversial, there’s some new discussion among the leaders in trauma resuscitation about pre-hospital thoracotomy. As Scott, has pointed out that it unlikely has much role in Auckland, its definitely interesting to see what’s being discussed.

Source: Roberton and Bulstrode,  Emergency department thoracotomies: Is it time we took them to the field? J Trauma vol 73 (no 5): 1070.

Full text pdf is available here (secure area limited to ADHB staff only – ADHB has subscription access for staff to these journals through the Philson Library at the University of Auckland School Of Medicine)