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• In the Surgicric 2 study, the authors noted the uncertainty In a meta-analysis, Hubble et al. identified prehospital surgi-
concerning the best cricothyrotomy technique: cal cricothyrotomy success rates between 84.8% and 94.2%.
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Of 34 patients who had a cricothyrotomy attempted in the
We know that in two studies comparing the Melker tech- combat prehospital setting, Barnard et al. reported a success
nique with other cricothyroidotomy devices and surgical rate of 82%. Two of the failed procedures were found to have
techniques, 70,71 the Melker technique was rated highest by had the cricothyrotomy tube placed in the wrong location.
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anaesthetists and had a higher success rate than a sur- During a 22-month period in the CENTCOM AOR, Mabry
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gical technique. However, in cases reported to NAP4 (4th and colleagues found a cricothyrotomy success rate of 62%
National Audit Project of The Royal College of Anaesthe- among battlefield medics at the POI (15/45). 65
tists and The Difficult Airway Society), cannula techniques
were associated with a worryingly high failure rate. In End-tidal carbon dioxide (EtCO ) monitoring has shown to be
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contrast, a more recent study and a meta-analysis have a highly effective adjunct in confirming ETT placement and
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found surgical techniques to have a high success rate. could likewise be used to confirm proper cricothyroidotomy
This was also demonstrated when surgical techniques tube placement. 82–85 EtCO monitoring is superior to relying
2
were used as a rescue technique in morbidly obese man- solely on clinical observations (breath sounds, O saturation)
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ikins. As highlighted by these opposing findings, it re- when confirming correct positioning of the cricothyrotomy
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mains unclear as to which cricothyroidotomy technique is tube.
superior. This is further supported by a systematic review Level of Evidence: B-NR (Nonrandomized)
by Langvad and colleagues which showed no clear ad-
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vantage of any device and no significant difference in suc- What are the advantages of using digital EtCO
cess rates. The recent Difficult Airway Society guidelines devices over colorimetric ones in the battlefield?
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have advocated a (bougie assisted) surgical technique as
the default technique for cricothyroidotomy. Digital capnography devices provide prehospital providers
with improved EtCO monitoring capability over colorimet-
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Studies analyzing the utilization of a bougie compared to stan- ric devices. 86,87 EtCO detection colorimetric devices provide
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dard surgical techniques have varied results. 73,77,78 The Diffi- cost efficient alternatives to digital capnography but with sig-
cult Airway Society promotes the use of a bougie, but there are nificant drawbacks. However, several breaths are required be-
notable risks such as prolonging the surgical technique proce- fore colorimetric will provide feedback, are sensitive to high
dure and perforating the bronchial tree from over insertion of humidity and can be prone to false positive conditions such
the bougie. 79 as exposure to gastric contents, cardiac arrest and esophageal
Level of Evidence: B-NR (Nonrandomized) placement. 86,87
Digital EtCO offers multiple advantages over colorimetric
What are the recommendations for cricothyrotomy 2
on the battlefield? monitoring, such as precision and continuous long-term moni-
toring, immediate results/feedback, respiration rate data, reus-
The bougie-aided open surgical technique has the most robust ability with disposable adapters, and, on some models, preset
justification for continued use. The existing TCCC guidelines alarms, graphing, and integration with electronic documen-
already provide evidence-based verbiage for this technique, tation. Digital EtCO confirmation and monitoring offers
2
and it should be the cricothyrotomy method of choice. Al- superior confirmation capability and is a must-do step when
ternatively, those that find difficulty adapting to a bougie aid performing cricothyrotomy.
technique may find an open surgical technique without bou- Level of Evidence: B-NR (Nonrandomized)
gie to be preferable. Pre-curved, cuffed, and flanged tracheos- Airway Change Wording
tomy-style cannulas provide optimal securing capability and 2023/2024 TCCC Guidelines for Airway Management and
success of insertion.
Respirations (changes in red text)
It is imperative that medics increase training proficiency of the Care Under Fire/Thread
cricothyrotomy technique as current military prehospital cri- N/A
cothyrotomy success rates are unacceptably low. Additionally,
it is critical that medics reliably confirm successful placement Tactical Field Care (Airway Management)
of a cricothyrotomy tube.
Level of Evidence: B-NR and C-LD (Nonrandomized and Lim- • Assess for unobstructed airway
ited Data) • If there is a traumatic airway obstruction or impending
traumatic obstruction, prepare for possible direct airway
What is the success rate of cricothyrotomy and intervention
does EtCO monitoring assist in confirming • Allow a conscious casualty to assume any position that
best protects the airway, to include sitting up and leaning
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cricothyrotomy placement? forward
As cricothyrotomy is the last option in the battlefield airway • Place unconscious casualty in the recovery position, head
management algorithm, it is critical that the procedure be tilted back; chin away from chest
trained to a “No-Fail” level of readiness. The New York Times • Use suction if available and appropriate
highlighted a U.S. Military incident in Africa involving a fail- • If the previous measures are unsuccessful, and the casualty’s
ure on the part of POI medic and CASEVAC PJ to identify a airway obstruction (e.g., facial fractures, direct airway in-
missed cricothyrotomy attempt, likely contributing to a Green jury, blood, deformation, burns) is unmanageable, perform
Beret’s death in 2018. 80 a cricothyrotomy using one of the following methods:

TCCC Change 24-1 | 53