- Cricothyroid membrane identification is frequently inaccurate with landmark technique1. Faster power-up times and increasing availability of portable US mean ultrasound is joining the arsenal of airway rescue technologies available for elective and emergency settings 2,3,4,5.
- We analysed usefulness and acceptability of a 3-step US technique teaching bundle “Guildford Cricothyroid membrane Ultrasound Technique (G-CUT)” to senior anaesthetists (ST5+).
Methods: Local R&D approval was gained; participants read and signed consent forms.
- CTM of an NHS staff member (BMI 32) was marked with invisible UV pen and covered a with Tegaderm™.
- Participants marked CTM needle puncture site with pen; 1st using landmark technique, 2nd US assisted (untrained), 3rd with US (post “G-CUT” training).
- Training (10 minutes) focussed on pattern recognition: rapid stepwise identification of 3 key midline structures cepahalad to caudal using transverse US.
- Anaesthetists graded confidence, ease of CTM identification and preferred method, completing an anonymous questionnaire between each of the attempts in the cycle.
- 27 anaesthetists (8 ST5-7s, 3 SAS and 16 Cons)
- 33% correctly identified CTM with landmark technique. Average self rated confidence and ability was 6.6/10 (range 2-9).
- 96% correctly identified CTM with US after “G-CUT” training. Average self rated confidence and ability was 7.7/10 (range 4-10). P<0.001
Figure 1i) Successful Identification of CTM (%) ii) Confidence in CTM identification (x/10)
- Average ease of use of rating for “G-CUT” was 7.6/10 (0 = very difficult, 10 = very easy)
- Median increases in self rated ability from 7 to 8/10 was significant. (P= 0.009)
- ST5-7s reported greater increases in confidence (+1.4) vs SAS (+1.3) or Consultants (+0.97).
- Participants would “definitely (55%)” or “may (44%)” consider using “G-CUT” method.
- Despite small study numbers, this training method pilot demonstrated a positive impact in a short timeframe and resulted in high user preference.
- “G-CUT” could help improve success in elective or emergency cricothyroidotomy.
References: 1. Can J Anesth/J Can Anesth DOI 10.1007/s12630-015-0326-y
2. Am J Emerg Med 2008; 26: 852-6 3. Ann Fr Anesth Reanim 2014; 33: 163-6 J.
4. Anaesth. (2015) 114 (6):1003-1004.doi: 10.1093/bja/aev123
5. Anaesthesia, 2010, 65, pages 889–894 doi:10.1111/j.1365-2044.2010.06425.x