Laryngeal handshake technique in locating the cricothyroid membrane: a non-randomised comparative study

Abstract

Background: Evaluation of the anterior neck anatomy is used to identify the cricothyroid membrane (CTM) before front of neck airway access. This has been traditionally performed using palpation which results in misidentification of the CTM in a high proportion of subjects. The 'laryngeal handshake' is currently advocated by the Difficult Airway Society as the method to identify the CTM. We sought to investigate the accuracy of this technique in females. Methods: Five clinicians were asked to identify the CTM using the 'laryngeal handshake' technique in a total of 45 anaesthetised females (Group L) and by conventional palpation in 45 controls (Group P). We measured and analysed the distance to actual CTM using ultrasound, the time to identification, and perceived difficulty using a visual analogue scale. Results: Successful identification of the CTM occurred in 28/45 (62%) patients in Group L vs 15/45 (33%) in Group P [P¼0.006; mean difference, 29%; 95% confidence interval (CI), 21e39%]. Distance to the CTM (P¼0.012) and visual analogue scale (P¼0.012) were significantly reduced in Group L. Mean time to CTM identification was greater in Group L at 31 (5.6) s, compared with Group P, which took 18 (5.5) s (P<0.001). The midline was accurately identified more frequently in Group L than in Group P (39/45 vs 28/45, P¼0.008). Conclusions: The 'laryngeal handshake' method of palpation is more accurate but takes longer than conventional palpation technique in locating the CTM and the midline. This is of particular relevance if a vertical incision is required to perform front of neck access when anatomy is indistinct.

The effect of i-gel® insertion on the accuracy of cricothyroid membrane identification in adult females: a prospective observational study

“…8,24 Although the study designs are different, the accuracy rates reported with the i-gel ® in place are similar to that with the laryngeal handshake technique (66% vs 62%). 25 Combined, these studies reflect the fact that although optimising technique may increase success rates, palpation alone does not seem to result in accuracy rates of more than two-thirds in females, and although palpation techniques are pragmatic they are distinctly inferior to focused airway ultrasound in terms of accuracy.…”

The effectiveness of educational methods for cricothyroid membrane identification by dental students: A prospective study using neck photographs and tracheotomy trainers

“…The middle finger and thumb are made to rest on the cricoid cartilage, and the index finger is used for palpating the CTM (Frerk et al, ). Moreover, the laryngeal handshake method has been shown to result in a higher CTM identification rate (62%) than the conventional method (33%; Drew & AcCaul, ). For this reason, it seems better to teach students this method in future.…”

Cricothyroidotomy in the emergency setting: indications, techniques and outcomes

“…The management of CICO scenario is a critical time and delayed or failed emergency cricothyroidotomy leads to acute cerebral hypoxia and death [16].…”

“…As reported by this author, the maneuver is performed with the thumb and the middle finger of the dominant hand identifying the hyoid and thyroid laminae, stabilizing the larynx between these two fingers, and moving down the neck to palpate the cricothyroid membrane with the index finger. After that the index finger of the dominant hand is substituted by that of the non-dominant hand and the dominant hand stabilized on the sternum is used to make the procedure [16,34].…”