Comparison of the Speed and Success of Endotracheal Intubation between BOUGIE and Flexible Video Laryngoscope on the CPR on Manikin by Emergency Residents

Reza Yazdani, Mehrdad Vosough Rouhani and Seyed Ashkan Tabibzadeh Dezfuli^*

^*Correspondence: Seyed Ashkan Tabibzadeh Dezfuli, Trauma and Emergency Medicine Research Center, Hormozgan University of Medical Sciences, Iran, Email:

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Introduction

The permanent brain damage starts after 4 minutes oxygen deprivation and if this time prolongs to 5 minutes, heart failure also will happen [1]. The evaluation of airways is the first action and maybe it is the most important part of the emergency patient’s recovery and there would be a need for intubation in many cases [2]. Intubation is not an easy and safe task and it is one of the most stressful medical tasks even for expert anesthesiologists and it imposes high levels of stress to them [3].

The anesthesiologists encounter with hard intubation cases in 1%-5% to 8% of general anesthesia [4]. John Bis invented the first video laryngoscope according to Pott et al. [5]. Video laryngoscopes have a tiny special camera on their pier, which provides the possibility of indirect monitoring of glut on screen by entering into mouth or nose. Since video laryngoscopy systems allow for easier intubation in more complicated cases, ambulatory surgery centers can increase their patient base.

Clinical studies show that video laryngoscopy improves intubation success rate. Video laryngoscopy has significant advantages for treating more complicated cases, but also benefits average patients with less trauma and quicker intubation times. Their application has expanded during intubation or laryngoscopy since early 21^st century [6]. Since the invention of video laryngoscope, many of them have introduced into market which most of them are not available due to public acceptance. Some of them, which gained attention by anesthesiologists and emergency specialists, can be divided into major groups: the first group of video laryngoscopes which remained loyal to their ancestors such as C-MAC and McGrath. The second group has a rod shape pier for adjusting to the airway which variety of flexible and rigid video laryngoscopes are counted as the members of this group.

The third group is the video laryngoscopes, which have a channel for inserting ETT tube, which include Pentax and airtraq types [7]. One of other auxiliary devices in intubation is Bougie or plastic flexible tube. This device is a semi-rigid guide tool in different forms that helps the piping inside the chip by crossing the vocal cord and allowing the ETT tube to slip over itself. Its application was explained by Mackintosh about 60 years ago [8].

Although training the piping into chip is carried out by numerous intubations for the patients who demand reliable airways theoretically and practically, application of educational moulages and mannequins has also increased significantly which seems to be a suitable alternative because of lowering the educations risks and practice on the real patients [7]. Considering the need for an auxiliary device in these intubation condition and different access to video laryngoscope and Bougie in different emergency centers of the country and lack of budget and educational potential for preventing the awful consequences because of delay in opening reliable airway, this research was carried out to compare the speed and success of intubation on educational moulage by video laryngoscope with the help of Bougie.

The video laryngoscope is applied newly in Iran emergency centers and lack of sufficient articles for investigating their abilities for serving the patients, is another aims of this study.

Materials and Methods

This study was approved by the ethics committee of Hormozgan University of Medical Science (Ethics Code: A-10-3434-1). The participants in this interferential study were a non-homogeneous group comprised of all residents of Hormozghan medical school (18 residents) who finished their one-month medical training course with different experiences from managing airways.

Research protocol

At first and before intubation, the training course was carried out by medicine professors and also specialists who are expert in working with flexible video laryngoscope. The theoretical and practical intubations were thought to all residents by this device and after one practice intubation course, all residents were transferred to skill lab.

After this stage, they practiced intubation on the educational moulages by recording it by the project executive. All records were calculated in hundredth of a second. About Bougie in another session after displaying the related educational film and practical description on moulage, the intubation was done and the results were recorded by project executive. If the intubation prolonged more than 30 seconds, it did not end up due to risks but that case was recorded as a failed case. Each resident performed 5 intubation by each one of the investigated devices in the project.

In both researches, one practice moulage with standard airway Mallampati grade I and tube 7.5. The intubation time was considered since the positioning of laryngoscopes in the patients mouth until the observation of ventilated lungs.

Statistical analysis

The collected data were analyzed by SPSS21 software. The data were reported as mean ± standard deviation (Mean ± SD). The analysis of variance (ANOVA) and Tukey post-hoc test was used to compare difference between the groups. A level of p<0.05 was considered as significant.

Results

After investigating the data, the results revealed that 55.6% of the participants were female and 44.4% were male and 38.9% of them were fresh man residents, 33.3% were sophomore residents and 27.8% were junior residents. To compare the essential time for intubation with video laryngoscope for the residents in different entrance years, variance analysis was used. The results of this test are showed in Table 1.

Table 1: Statistical indexes for the time needed for intubation by video laryngoscope for the residents in different entrance year

The results of variance analysis in Table 1 present that there is a significant difference between the average required time for intubation by video laryngoscope for the residents with different entrance year to the hospital. By Tukey test, the results presented that the average required time for intubation by video laryngoscope is the longest for the fresh man residents and the average time for the sophomore and junior residents did not reveal a significant difference (p˃0.05).

The results of the variance analysis in Table 2 present that there is a significant difference between the required time for intubation by Bougie for the residents with different entrance year to the hospital. In the following, in order to understand these differences, Tukey test was applied. The results show that the essential required time for intubation by Bougie is the longest for the freshman residents and it has a significant difference with other residents (p<0.05). The average time for the sophomore residents has a remarkable difference with other residents and it stands in the second rank (p<0.05). In addition, the average time for the junior residents is the shortest among all others and it stands in the third rank (p<0.05). To compare the required time for intubation by video laryngoscope and Bougie for the residents with different entrance year, the paired t-test was used. The results of this test are shows in Table 3.

Table 2: The statistical indexes of the required time for intubation by Bougie for the residents with different entrance year

Table 3: The statistical indexes of the required time for intubation by Bougie and video laryngoscope for the residents with different entrance year

The findings of paired t-test in Table 4 indicate that p-value is less than 0.05 for each 3 different entrance years and in total which shows a significant difference between the average required time of intubation for the residents with different entrance years by video laryngoscope and Bougie. Figure 1 represents this significant difference clearly.

Table 4: The statistical indexes of the successful intubation times by Bougie and video laryngoscope for the residents with different entrance year

Figure 1. The average required time for comparing intubation by video laryngoscope and Bougie for the residents with different entrance year

To compare the successful intubation times by video laryngoscope and Bougie for the residents with different entrance year, the ratio test was applied. The results of this test are presented in Table 4.

The findings of the ratio test in Table 4 reveal that pvalue in each 3 different entrance years and total are less than 0.05 which indicate for the significant difference between the successful intubation times by video laryngoscope and Bougie for the residents with different entrance years. Considering the frequency percentage of successful intubation, it was clarified that Bougie method is much more successful than the video laryngoscope method.

Discussion

There are numerous articles about the application of different video laryngoscope types for piping inside the chip [9]. In a study done by Lim et al. on educational Mannequins with Mallampati grade III which only epiglottis was visible, two rigid video laryngoscope and Macintosh laryngoscope methods were compared with each other. Anesthesiologist observed that rigid video laryngoscope needs less time for intubation. 23.5 seconds versus 70.5 seconds (p=0.001) [10]. Furthermore, another research by Jungbauer et al. was carried out to compare video laryngoscopy and direct laryngoscopy on 200 patients with Mallampati grade 3 to 4. In this article also the required intubation time by video laryngoscope was shorter obviously. 40 seconds versus 60 seconds (p=0.017) [11]. In the present study, the average total times were 23.75 seconds and 16.37 seconds for video laryngoscope and Bougie among all residents respectively which present intubation by Bougie takes less time. Contrary to these results, there are also some other studies that did not discover any advantage for video laryngoscope in front of conventional laryngoscope. For example, in a study done by Kim et al. on practice and educational Moulage for comparing rigid video laryngoscope and conventional laryngoscope, 4 scenarios were evaluated; the first one: normal shape of airways, second: Moulage, imitating the physical constraints of cervical vertebrae, third: simulation of tongue edema and then combinational model of tongue edema and physical constraints of cervical vertebrae. In all 4 models, the research of video laryngoscope could not have a clear advantage on laryngoscopes regarding speed and position [12]. The researches have revealed that video laryngoscope can create a better gothic image [11]. However, having a clear gothic image does not guarantee for fast and successful intubation because transmitting the ETT tube throw vocal cords needs stereoscopic and psychomotor skills which will increase by practice for sure [10,13]. Furthermore, Curtis carried out a study on awake overweight patients by flexible video laryngoscope in 2012. He found out that the presence of blood and mucus along the respiratory makes the application of this scope for piping inside the chip so hard or even impossible [14]. In contrast, those researches which have done on the Bougie’s potentials in patients intubation who have problems in their airways, have mentioned the advantage of this method over other methods such as direct laryngoscopy mostly. For example: A research done by Noguchi et al. which was published in Insensoil journal, application of Bougie by means of stylet in the patients who feel pressure on Cricoid cartilage while intubation was compared for the convenience of these patients. He observed that pressure on Cricoid cartilage can make the intubation too hard and application of Bougie can make it more convenient while it is not true for stylet. In that research, the required time for intubation by Bougie was measured 33 seconds [15] while this time is low with 16.37 seconds as the total average but it was in agreement regarding the increased speed and success rate. In addition, another research was done by Komatsu et al., which was entitled “comparing the rigid scope of airway and Bougie for intubation of the patients with cervical vertebrae complications ” . The average intubation speed by Bougie was measured 49 seconds [16] which was longer than our findings but it was shorter than the time required for rigid scope. In this research, the success of intubation by Bougie was calculated 95.8% which this amount was 97.8% in our research. Another research by Messa et al. which was entitled “ the success of conventional and Bougie laryngoscopy by educational Moulage and simulation of difficult airways ” [17]. The success of intubation by Bougie was 94% and it was much higher than conventional laryngoscopy [15,16]. The average required time for intubation by Bougie was calculated 20.4 seconds [17].

Conclusions

Considering the results of this research, it can be concluded that both video laryngoscope and Bougie devices have been shown as a reliable and effective auxiliary devices. Due to the availability, fast education and safety, it is a unique device which is one of the best devices and it is suggestible in emergency unit for opening reliable airways during hard intubations. It seems BOUGIE with high rate of success and availability can be a good auxiliary device in hard intubation cases in emergency.

Acknowledgments

The authors would like to appreciate the contribution of all the participants as well as the consulting services of the Center for the Development of Clinical Research at Shahid Mohammadi Hospital in Bandar Abbas.

Author Contributions

All authors contributed toward data analysis, drafting and revising the paper and agreed to be responsible for all the aspects of this work.

Conflict of Interest

The authors declare that there is no conflict of interest regarding the publication of this manuscript.

References

1. Hosseinkhan Z, Ebrahim SA, Arbabi S. Airway: Historical background, preoperative assessment and management of elective and emergency airway problems. Tehran Univ Med J 2007; 65:1-12.
2. Stone DJ, Gal TJ. Airway management, Anesthesia. 7th ed. Philadelphia: Churchill Livingstone 2009; 1414-52.
3. Birnbach DJ, Browne IM. Anesthesia for Obstetrics In: Miller’s Anesthesia. Miller RD. Philadelphia: Churchill Livingstone 2005; 13:2310-30.
4. Lee A, Fan LT, Gin T, et al. A systematic review (meta-analysis) of the accuracy of the Mallampati tests to predict the difficult airway. Anesth Analg 2006; 102:1867-78.
5. Pott LM, Murray WB. Review of video laryngoscopy and rigid fiberoptic laryngoscopy. Curr Opin Anaesthesiol 2008; 21:750-8.
6. Nouruzi-Sedeh P, Schumann M, Groeben H. Laryngoscopy via macintosh blade versus glidescopesuccess rate and time for endotracheal intubation in untrained medical personnel. Anesthesiology. J Am Soc Anesthesiol 2009; 110:32-7.
7. Behringer EC, Kristensen MS. Evidence for benefit vs novelty in new intubation equipment. Anaesthesia 2011; 66:57-64.
8. Macintosh R. An aid to oral intubation. Br Med J 1949; 1:28-35.
9. Timmermann A, Cal C, Nickel E, et al. Simulation and airway management. Anesthetist 2005; 54:582-7.
10. Lim TJ, Lim Y, Liu EH. Evaluation of ease of intubation with the GlideScope or Macintosh laryngoscope by anaesthetists in simulated easy and difficult laryngoscopy. Anaesthesia 2005; 60:180-93.
11. Jungbauer A, Schumann M, Brunkhorst V, et al. Expected difficult tracheal intubation: A prospective comparison of direct laryngoscopy and video laryngoscopy in 200 patients. Br J Anaesth 2009; 102:546-50.
12. Kim HJ, Chung SP, Park IC, et al. Comparison of the GlideScope video laryngoscope and Macintosh laryngoscope in simulated tracheal intubation scenarios. Emerg Med J 2008; 25:279-82.
13. Kaplan MB, Hagberg CA, Ward DS, et al. Comparison of direct and video-assisted views of the larynx during routine intubation. J Clin Anesth 2006; 18:357-62.
14. Curtis R. Awake video laryngoscopy-assisted tracheal intubation in the morbidly obese. Anesthesia 2012; 67:796-807.
15. Noguchi T, Koga K, Shiga Y, et al. The gum elastic bougieasestracheal intubation while applying cricoid pressure comparedto a stylet. Can J Anesth 2003; 50:712-21.
16. Komatsu R, Kamata K, Hoshi I, et al. Airway scope and gumelasticbougie with Macintosh laryngoscope for tracheal intu-bation in patients with simulated restricted neck mobility. Br J Anaesth 2008; 101:863-79.
17. Messa MJ, Kupas DF, Dunham DL. Comparison of bougie-assisted intubation with traditional endotracheal intubation in a simulated difficult airway. Prehosp Emerg Care 2011; 15:30-45.