Comparison of Airway Management Methods in Entrapped Patients: A Manikin Study

Assessment of Success and Ease of Insertion of ProSeal™ Laryngeal Mask Airway versus I-gel™ Insertion by Paramedics in Simulated Difficult Airway Using Cervical Collar in Different Positions in Manikins

Background:

Tracheal intubation, a critical intervention, performed by paramedics for airway management in trauma, has an unacceptably low success rate due to difficult airway, restricted access, and inexperience. Thus, the use of supraglottic devices to achieve ventilation has gained popularity.

Aims:

We aimed to compare the success rate, time to achieve ventilation, and ease of insertion of two popular supraglottic devices, ProSeal™ laryngeal mask airway (PLMA) and I-gel™, in simulated difficult airway with limited access in manikins in different positions which were supine, head against the wall, and sitting position like in car seat.

Settings and Design:

This was a prospective interventional study.

Materials and Methods:

After a brief training, 35 paramedics were asked to insert I-gel™ and PLMA in a manikin with cervical collar in 3 positions: head end free (Group A), head against the wall (Group B), and sitting position (Group C), to simulate difficult airway. Success rate and time to achieve ventilation in each position were noted. Each participant graded ease of insertion.

Statistical Analysis:

Statistical analysis was performed using SPSS 24.0. Categorical variables were analyzed using a Pearson's Chi-square test. Continuous variables were analyzed using the Kolmogorov–Smirnov test. If there was a normal distribution, a paired t-test was performed. Otherwise, a Wilcoxon signed-rank test was performed. P < 0.05 was considered statistically significant.

Results:

Success rate with I-gel™ was significantly higher than PLMA, 91% versus 77% in Group A, 100% versus 88% in Group B, and 100% versus 74% in Group C. Time to achieve ventilation was shorter with I-gel™ than PLMA, 8.9 versus 15 s in Group A (P < 0.001), 13.1 versus 21.3 s in Group B (P < 0.01), and 18.5 versus 30.3 s in Group C (P < 0.001).

Conclusion:

I-gel™ can be an effective device to achieve ventilation in difficult airway with limited access in trauma. More studies are required to validate its success and safety.

Comparing Four Video Laryngoscopes and One Optical Laryngoscope with a Standard Macintosh Blade in a Simulated Trapped Car Accident Victim

Background

Tracheal intubation still represents the “gold standard” in securing the airway of unconscious patients in the prehospital setting. Especially in cases of restricted access to the patient, video laryngoscopy became more and more relevant.

Objectives

The aim of the study was to evaluate the performance and intubation success of four different video laryngoscopes, one optical laryngoscope, and a Macintosh blade while intubating from two different positions in a mannequin trial with difficult access to the patient.

Methods

A mannequin with a cervical collar was placed on the driver's seat. Intubation was performed with six different laryngoscopes either through the driver's window or from the backseat. Success, C/L score, time to best view (TTBV), time to intubation (TTI), and number of attempts were measured. All participants were asked to rate their favored device.

Results

Forty-two physicians participated. 100% of all intubations performed from the backseat were successful. Intubation success through the driver's window was less successful. Only with the Airtraq® optical laryngoscope, 100% success was achieved. Best visualization (window C/L 2a; backseat C/L 2a) and shortest TTBV (window 4.7 s; backseat 4.1 s) were obtained when using the D-Blade video laryngoscope, but this was not associated with a higher success through the driver's window. Fastest TTI was achieved through the window (14.2 s) when using the C-MAC video laryngoscope and from the backseat (7.3 s) when using a Macintosh blade.

Conclusions

Video laryngoscopy revealed better results in visualization but was not associated with a higher success. Success depended on the approach and familiarity with the device. We believe that video laryngoscopy is suitable for securing airways in trapped accident victims. The decision for an optimal device is complicated and should be based upon experience and regular training with the device.

A comparison of airway management devices in simulated entrapment-trauma: a prospective manikin study

INTRODUCTION

In the patient entrapped after a motor vehicle collision (MVC), advanced airway management may need to be performed before extrication. The aim of this study was to compare four airway management devices utilized by paramedics in a simulated entrapped patient.

METHODS

Twenty-six paramedics performed advanced airway management on a manikin seated in the driver's seat (right side) of a car. Access was through the opened door only. The airway devices were the Macintosh laryngoscope and the Airtraq optical laryngoscope to facilitate the endotracheal intubation (ETI), the laryngeal mask airway (LMA) Supreme and the laryngeal tube (LT). Time to first successful ventilation and number of attempts required for successful placement were measured. Following each placement, participants rated the degree of difficulty. For ETI, participants ranked the achieved glottic view using Cormack-Lehane grades (CLG). Finally, participants were asked which airway management device they preferred.

RESULTS

The LMA Supreme had the shortest mean time to first successful ventilation (16.7 s, CI [0.95] 14.9-18.6). Insertion of the LMA Supreme and ETI with the Macintosh laryngoscope had 100% first-attempt success. The LMA Supreme was rated least difficult to insert (mean score 1.7/10 (CI [0.95] 1.2-2.1)). Compared to the Macintosh, the Airtraq laryngoscope facilitated superior laryngoscopy (CLG I view 46.2% and 80.8%, respectively). Most participants (10/26; 38%) chose the Macintosh laryngoscope as their preferred technique, followed closely by the LMA Supreme (9/26; 35%).

CONCLUSION

The LMA Supreme took the least amount of time and was the easiest to be inserted. Extraglottic airway devices may be beneficial alternative airway management devices to be considered by paramedics in the entrapped patient. Endotracheal intubation using the Macintosh laryngoscope was performed competently by participating paramedics. The Airtraq enabled superior laryngoscopy but resulted in poorer first-pass success rate.