TY - JOUR

T1 - Depth to the airway lumen at the level of the cricothyroid membrane measured by ultrasound

AU - Athanassoglou, Vassilis

AU - Hughes-Jones, Hannah

AU - Hadjipavlou, George

AU - Teoh, Wendy Hl

AU - Kristensen, Michael S

AU - Vanner, Richard

N1 - This article is protected by copyright. All rights reserved.

PY - 2019/8/22

Y1 - 2019/8/22

N2 - BACKGROUND: Knowing the likely depth to the airway before emergency cricothyroidotomy may improve success in cases where it cannot be measured. Our aim was to measure the depth to the airway at the cricothyroid membrane by ultrasound in a large group of adult patients.METHOD: Prospective, observational study in two centres, Oxford and Gloucester. Patients presenting for a large variety of surgical operations were studied. Patients under 18 years old; pregnant; critically ill; had a history of neck surgery not included. Ultrasound examination was performed pre-operatively while participants lay supine with their head and neck extended, with light transducer pressure. We measured depth to the airway lumen in mm; age; weight; height and sex.RESULTS: In total 352 patients were studied. We found that depth to the airway lumen strongly correlated with weight (r=0.855, p<0.001) and to a lesser extent body mass index (r=0.781, p<0.001) but did not correlate to sex. Statistical analysis produced an equation to predict upper 95% CI of depth to the airway from the patient's weight: Depth to the airway lumen in mm = (0.13 x weight in kg) + 0.86.CONCLUSIONS: If ultrasound measurement is not possible before emergency cricothyroidotomy, the clinician could use our results to predict the depth to the airway by using the patient's weight. If the upper 95% CI were used as the depth of incision, it would enter the airway in 39 out of 40 patients of that weight, without damage to posterior structures in those with a shallower airway. This article is protected by copyright. All rights reserved.

AB - BACKGROUND: Knowing the likely depth to the airway before emergency cricothyroidotomy may improve success in cases where it cannot be measured. Our aim was to measure the depth to the airway at the cricothyroid membrane by ultrasound in a large group of adult patients.METHOD: Prospective, observational study in two centres, Oxford and Gloucester. Patients presenting for a large variety of surgical operations were studied. Patients under 18 years old; pregnant; critically ill; had a history of neck surgery not included. Ultrasound examination was performed pre-operatively while participants lay supine with their head and neck extended, with light transducer pressure. We measured depth to the airway lumen in mm; age; weight; height and sex.RESULTS: In total 352 patients were studied. We found that depth to the airway lumen strongly correlated with weight (r=0.855, p<0.001) and to a lesser extent body mass index (r=0.781, p<0.001) but did not correlate to sex. Statistical analysis produced an equation to predict upper 95% CI of depth to the airway from the patient's weight: Depth to the airway lumen in mm = (0.13 x weight in kg) + 0.86.CONCLUSIONS: If ultrasound measurement is not possible before emergency cricothyroidotomy, the clinician could use our results to predict the depth to the airway by using the patient's weight. If the upper 95% CI were used as the depth of incision, it would enter the airway in 39 out of 40 patients of that weight, without damage to posterior structures in those with a shallower airway. This article is protected by copyright. All rights reserved.

U2 - 10.1111/aas.13464

DO - 10.1111/aas.13464

M3 - Journal article

JO - Acta Anaesthesiologica Scandinavica

JF - Acta Anaesthesiologica Scandinavica

SN - 0001-5172

ER -