Auckland HEMS video laryngoscopy trial

By Dr James LeFevre

Auckland HEMS is currently trialling the Storz C-MAC Videolaryngoscope (VL), and we are also aiming to trial this device in the Auckland Adult Emergency Department soon.

https://i1.wp.com/www.carolinashealthcare.org/images/CMC/Storz-Video-LaryngoscopeMd.jpg

There is much debate in the FOAMEd community regarding the place of the VL in Emergency airway management, with often quite polarised views, and the published literature is yet to catch up with the uptake of the various multitude of VL devices.

There are many different Videolaryngoscopes out there, but they generally boil down to two basic types:

Those that use hyperangulated blades to “see around the corner” (such as the Glidescope that is currently available in Auckland ED), and those that use Macintosh-style blades that are connected to a video screen (Such as the Storz C-MAC).

Hyperangulated VL blades often allow superb laryngeal visualisation, with the downside that tube delivery requires a different technique with an angulated stylet, whereas Macintosh-style blades allow for the use of the same tube delivery technique through direct laryngoscopy (looking directly at the larynx) or indirect laryngoscopy (looking at the screen to see the larynx).

Although the literature is still not clear on this issue, it would appear that some patients are more easily intubated with direct laryngoscopy with a standard blade, and others are more easily intubated with a hyperangulated blade, so intuitively it makes sense to have both options available.

The C-MAC we are trialling has a Mac-3, Mac-4, and a hyperangulated D-Blade option. Potential advantages include the ability to turn the screen away from the airway operator whilst using the Mac blade to allow teaching and the resuscitation team to see what sort of actual view is being obtained (sometimes this info just ain’t forthcoming in real time!), allow assistants other than the airway operator to perform suction under visualisation, and has a hyperangulated blade should a poor view be obtained with a standard Mac blade.

Attached below are some FOAM links which discuss the differences between VL and DL, how intubation techniques differ, and some of the pros and cons to each technique. There is also some published literature in the password protected section, happy reading.

Lifeinthefastlane.com on Videolaryngoscopy at:

http://lifeinthefastlane.com/education/ccc/direct-versus-video-laryngoscopy/

http://lifeinthefastlane.com/education/ccc/video-laryngoscopy/

PHARM (Prehospital and Retrieval Medicine) at:

http://prehospitalmed.com/2012/09/07/why-video-will-never-kill-the-direct-laryngoscope-star/

EMCRIT Scott Weingart versus Paul Mayo Debate – Direct versus Video laryngoscopy at:

http://emcrit.org/podcasts/has-video-laryngoscopy-killed-the-dl-star/

Richard Levitan at:

http://www.epmonthly.com/subspecialties/technology/video–direct-laryngoscopy-/

http://www.epmonthly.com/features/current-features/four-secrets-to-video-laryngoscopy-/

Relevant literature:

A Comparison of the C-MAC Video Laryngoscope
to the Macintosh Direct Laryngoscope for Intubation in the Emergency
Department

The C-MAC videolaryngoscope for prehospital emergency intubation: a prospective, multicentre, observational study

Comparison of video laryngoscopy and direct laryngoscopy in a critical care transport service

Assessing the efficacy of video versus direct laryngoscopy through retrospective comparison of 436 emergency intubation cases

A systematic review of the role of videolaryngoscopy in successful orotracheal intubation

Glidescope video-laryngoscopy versus direct laryngoscopy for
endotracheal intubation: a systematic review and meta-analysis

Effect of video laryngoscopy on trauma patient survival: A
randomized controlled trial

Variables associated with successful intubation attempts using video laryngoscopy: a preliminary report in a helicopter emergency medical service

Click HERE for full text version of the articles above (secure area limited to ADHB staff)

Emergency Medicine = Combat Aviation!

There is currently a huge amount of interest in lessons that medicine can learn from aviation, including concepts like CRM and the use of checklists. Efforts are being made to select and integrate these concepts into a form specific to emergency medicine – Andy Buck’s blog Resus Room Management is a great example of this, and is well worth a read.

Joe-NovakJoe Novak, an emergency physician who is a former F15 pilot (!) feels that due to its chaotic nature emergency medicine is analogous to combat aviation! These concepts are discussed in a lecture presented on Scott Weingart’s emcrit.org

Click HERE for the show notes and podcast

 

.

In combat aviation:

  1. Aviate
  2. Navigate
  3. Communicate

In EM & Critical Care:

  1. Resuscitate
  2. Differentiate
  3. Communicate

Have we been taught all wrong?…A new location of needle decompression?

Where do you insert the needle for pneumothorax decompression?

Easy!

Is it time to rethink 2nd intercostal space, mid clavicular line for site of needle decompression?

Is it time to rethink 2nd intercostal space, mid clavicular line for site of needle decompression?

“2nd intercostal space (ICS), mid-clavicular line (MCL)” – this has been drilled into all of us since we began training and caring for critically ill patients. Ever since we began as pre-hospital care providers or took our first  Advanced Trauma Life Support have we used the 2nd ICS, MCL and assumed it to be optimal.

Well recently some studies have started looking at whether we should consider an alternative location. There is some evidence to suggest that the traditional anterior approach may reduce kinking and in the combat environment, it might be preferred (Beckett A et al. J Trauma 2011). However, if it will never enter into the pleural space then kinking becomes irrelevant.  While the utility of needle decompression vs. simple finger thoracostomy followed by chest tube insertion can be debated, in the pre-hospital setting, needle decompression remains within the realm of paramedics and may at times be most practical. Also, unless you’re rapidly prepared to perform a chest tube with sterility in mind, needle decompression may be a better option. Thus, such studies remain important.

A recently published study (from the USC trauma surgeons in Los Angeles who seem to publish everything related to trauma) compared the 2nd ICS , MCL with the 5th intercostal space, anterior axillary line (AAL).

CT chest exams of 120 trauma patients were used in the study. Measurements were taken at both sites and compared. Interestingly, the authors stratified patients into 4 BMI categories then analyzed the data based on these groupings.

Results

  • Overall, the 5th ICS AAL was a superior site for needle decompression based on chest wall measurement
  • Chest wall thickness was thicker at the 2nd ICS MCL compared to the 5th ICS AAL (by 0.5cm)
  • As only 16% of patients had chest walls thicker than the standard 5cm needle commonly used. Compared to 42% probable failures if placed at the 2nd ICS MCL.
  • Based on BMI stratification, needle decompression at the 5th ICS AAL would be possible for all but the highest BMI while at the 2nd ICS MCL would likely fail except in the lowest group

Take home message – given this was not a clinical study (only based on CT scans) it’s not quite practice changing. We don’t know the potential risks of cardiac injury using the 5th ICS AAL or whether it can be feasibly performed without kinking. However, this technique could be considered if the 2nd ICS MCL fails, especially in high BMI patients and clearly any benefits outweigh the risks – for instance if the patient has already arrested.

STUDY ABSTRACT

Inaba K et al Radiologic evaluation of alternative sites for needle decompression of tension pneumothorax. Arch Surg 2012;147:813-8

OBJECTIVE: To compare the distance to be traversed during needle thoracostomy decompression performed at the second intercostal space (ICS) in the midclavicular line (MCL) with the fifth ICS in the anterior axillary line (AAL).

DESIGN: Patients were separated into body mass index (BMI) quartiles, with BMI calculated as weight in kilograms divided by height in meters squared. From each BMI quartile, 30 patients were randomly chosen for inclusion in the study on the basis of a priori power analysis (n = 120). Chest wall thickness on computed tomography at the second ICS in the MCL was compared with the fifth ICS in the AAL on both the right and left sides through all BMI quartiles.

SETTING: Level I trauma center.

PATIENTS: Injured patients aged 16 years or older evaluated from January 1, 2009, to January 1, 2010, undergoing computed tomography of the chest.

RESULTS: A total of 680 patients met the study inclusion criteria (81.5% were male and mean age was 41 years [range, 16-97 years]). Of the injuries sustained, 13.2% were penetrating, mean (SD) Injury Severity Score was 15.5 (10.3), and mean BMI was 27.9 (5.9) (range, 15.4-60.7). The mean difference in chest wall thickness between the second ICS at the MCL and the fifth ICS at the AAL was 12.9 mm (95% CI, 11.0-14.8; P < .001) on the right and 13.4 mm (95% CI, 11.4-15.3; P < .001) on the left. There was a stepwise increase in chest wall thickness across all BMI quartiles at each location of measurement. There was a significant difference in chest wall thickness between the second ICS at the MCL and the fifth ICS at the AAL in all quartiles on both the right and the left. The percentage of patients with chest wall thickness greater than the standard 5-cm decompression needle was 42.5% at the second ICS in the MCL and only 16.7% at the fifth ICS in the AAL.

CONCLUSIONS: In this computed tomography-based analysis of chest wall thickness, needle thoracostomy decompression would be expected to fail in 42.5% of cases at the second ICS in the MCL compared with 16.7% at the fifth ICS in the AAL. The chest wall thickness at the fifth ICS AAL was 1.3 cm thinner on average and may be a preferred location for needle thoracostomy decompression