Hindawi Publishing Corporation
Case Reports in Anesthesiology
Volume 2015, Article ID 453547, 4 pages
http://dx.doi.org/10.1155/2015/453547

Case Report
Tracheal Intubation with Aura-i and aScope-2: How to Minimize
Apnea Time in an Unpredicted Difficult Airway
Vittorio Pavoni,1 Valentina Froio,1 Alessandra Nella,1 Martina Simonelli,1Lara Gianesello,1 Andrew Horton,2 Luca Malino,3 and Massimo Micaglio1
1Department of Anesthesia and Intensive Care, University-Hospital Careggi, Largo Brambilla 3,50134 Firenze, Italy
2Faculty Practice Group, University of California, Los Angeles, CA 90095, USA
3Ambu Srl, Via Paracelso 18, Agrate Brianza, 20041 Milano, Italy
Correspondence should be addressed to Vittorio Pavoni; pvv@unife.it
Received 23 July 2014; Revised 5 December 2014; Accepted 24 December 2014
Academic Editor: Pavel Michalek
Copyright © 2015 Vittorio Pavoni et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The supraglottic airway’s usefulness as a dedicated airway is the subject of continuing development. We report the case of anobese patient with unpredicted difficult airway management in which a new “continuous ventilation technique” was used with
the Aura-i laryngeal mask and the aScope-2 devices. The aScope-2/Aura-i system implemented airway devices for the managementof predictable/unpredictable difficult airway. The original technique required the disconnection of the mount catheter from Aurai, the introduction of the aScope-2 into the laryngeal mask used as a conduit for video assisted intubation and then towards thetrachea, followed by a railroading of the tracheal tube over the aScope-2. This variation in the technique guarantees mechanicalventilation during the entire procedure and could prevent the risk of hypoventilation and/or hypoxia.

1. Introduction
Supraglottic airway devices (SADs) play a critical role inthe management of difficult airway and their use in patientswith difficult face-mask ventilation or failed tracheal intubation is widely recommended [1, 2]. Furthermore, SADs arewell described as conduits to facilitate tracheal intubation[3], although most devices require fiber-optic bronchoscope(FOB) guidance to increase the rate of success [4–6]. With theaim of minimizing apnea time during the entire procedure,
improving patient’s safety, a continuous ventilation techniqueduring the intubation procedure has been described, using amount catheter with a fiber-optic cap attached to the tracheal
tube (TT) [7].
We report a case of unpredicted difficult airway in which
fiber-optic intubation was performed using a new “continuous ventilation technique” with combination of the Aura-i
disposable laryngeal mask (Ambu A/S, Ballerup, Denmark)and the aScope-2 (Ambu A/S, Ballerup, Denmark).

The precurved disposable laryngeal mask Aura-i (AmbuA/S, Ballerup, Denmark) is a SAD designed to facilitate onestep tracheal intubation with FOB guidance [8], due to its
anatomically correct curve and the presence of a navigation
mark for guiding flexible scope. Its role has become still moreinteresting since the development of the aScope-2 (AmbuA/S, Ballerup, Denmark), a flexible intubation scope with its
high-resolution specific monitor. Both devices are single use
in order to reduce cross contamination and cleaning or repair
costs [9].

2. Case Report
A 55-year-old female was scheduled to undergo elective
cholecystectomy. Past medical history was significant forobesity (body mass index 31.2 Kg/m2 , obesity class I), tobaccosmoking, and mild chronic obstructive pulmonary disease,treated with short-acting 𝛽2 -agonists. Preoperative arterial blood gas analysis showed PaO2 66 mmHg, PaCO2

242 mmHg, HCO3− 29 mEq/L, pH 7.39, and BE −3.0. On
preoperative airway examination the Mallampati score oral
opening view was evaluated to be class 2, with mouth openingof approximately 4 cm, a thyromental distance of 6.5 cm, andjaw protrusion was estimated as grade B and we noted alsoslightly limited neck extension. The patient exhibited slightly
limited craniocervical extension. A borderline situation forpossible difficult intubation was identified, but except fora light increase of BMI, no predictor of difficult mask
ventilation was found. After routine monitoring, preoxygenation was performed and anesthesia was induced withpropofol 170 mg and fentanyl 150 mcg i.v. After confirmationof the ability to ventilate the patient’s lungs using a bagand mask, 80 mg of rocuronium was administered. Direct
laryngoscopy was then performed, which revealed a grade
III laryngeal view (Cormack and Lehane) due to a large
floppy epiglottis. One attempt of gum elastic bougie-assistedtracheal intubation technique was unsuccessful. A size 4
Aura-i laryngeal mask was then easily inserted and thecuff inflated up to a pressure of 50–60 cmH2 O. Satisfactory
ventilation was achieved in few seconds after connection tothe ventilator (Drager Primus, Dragerwerk AG & Co.) using a
volume controlled model (tidal volume 7 mL/kg, respiration
rate 10 per min, PEEP 5 cmH2 O) and we considered the useof the SAD to facilitate tracheal intubation. With the aim ofpreventing hypoxia during the procedure, reducing the timeof apnea, a variation in the intubation technique suggested
from the manufacturer was introduced. Without discontinuing mechanical ventilation, the aScope-2 was guided inside
the airway tube of Aura-i through a mount catheter with afiber-optic cap (DAR-Covidien) and both its position and its
anatomical relation with the glottis were checked. A partiallyobstructed view at the level of distal orifice of the Ambu-I LM
was noted during the initial view; this was probably caused
by malposition or downfolding of epiglottis. Following “upand down movements” of the LM, the view cleared up,
with full view of the glottis displayed on the monitor, andthe aScope-2 was withdrawn from the mask. The mountcatheter was disconnected from the ventilatory circuit for few
seconds to allow the distal end of a well lubricated 7.5 mm ID
TT to be partially inserted into the airway tube of Aura-i.
The TT cuff was inflated and the tube was connected toventilator with unchanged ventilation mode. Then TT cuff
was deflated and the TT was advanced over aScope-2 thatwas placed in the trachea and the TT connector hooked up
to the anaesthesia circuit (Figure 1). Without discontinuing
ventilation, the 630 mm insertion-cord of the aScope-2 was
first guided inside the TT through the fiber-optic cap of
the mount catheter and then into the airway tube of Aura-i
to gain a full view of the glottic opening from the end ofthe SAD.
The cuff of the tracheal tube was deflated and the tube wasthen advanced over the aScope-2 used as a guide. Connectorof the tracheal tube was attached to the anaesthesia circuit(Figure 1). Correct depth of the tracheal tube was checked andthe aScope-2 was subsequently withdrawn. The TT cuff wasinflated while the Aura-i cuff was deflated and kept in place,decreasing pressure on the pharyngeal mucosa. Anaesthesia
and surgery proceeded uneventfully.

Case Reports in Anesthesiology

MountcatheterTTAura-iFigure 1: The patient is mechanically ventilated through a tracheal
tube (TT) partially inserted in the airway tube of Aura-i and withthe cuff inflated.

3. Discussion
Hypoxia may complicate difficult airway management representing a life-threatening event [10]. Obese patients have anelevated risk of hypoxia as compared to the nonobese population. The use of a SAD has been recently recommendedin obese population instead of the face-mask ventilation inorder to ease airway management and administer PEEP, thus
preventing hypoxia [11].
Our patient did not show any feature that suggested
difficulty in face-mask ventilation; therefore the early placement of SAD appeared not essential. On the other hand,
our patient showed difficulty on direct laryngoscopy withtracheal intubation which was not predicted on the baseof preoperative airway evaluation, if we exclude Mallampati
class 2 and jaw protrusion grade B.
The usefulness of SADs both in unpredicted difficult
airway and in predicted difficult intubation with conventional
laryngoscopy was the subject of considerable interest [12, 13].
A number of studies have reported intubation through a SAD
using a blind technique or assisted by light wands, opticalstylets, and flexible fiber optic [14, 15]. Individual case reports
have also described a variety of techniques.
The aScope-2/Aura-i system implements airway devices
for the management of predictable/unpredictable difficult
airway. The light weight of the “ergonomically designed”
handle of the aScope-2 makes it easy to manipulate [16](Figure 2). Furthermore the aScope-2 is less rigid than afiberscope sparing the endotracheal tube to find resistance toprogression through the laryngeal mask and the vocal cords.
The portable monitor makes it easy to transport from one
operating room to the other one and makes the system evenmore simple and friendly to use. Both the Aura-i laryngeal
mask and the aScope-2 are disposable devices, so biologicalrisks are minimized and they can be used in patients with
infectious and transmissible diseases. They are always readyto use and there is no risk of damage during decontaminationand storage.

Case Reports in Anesthesiology

3

Conflict of Interests
The device laryngeal mask Aura-i and the aScope-2 areproducts of Ambu A/S (Ballerup, Denmark). Dr. L. Malino
is a technical representative employee of this company inItaly.

References

Figure 2: The aScope-2 with a transportable monitor.

The aScope-2 has a poor fiber-optic view comparing toa fiberscope and its tip is characterized by a lesser rangeof movement, with a limited angulation [9]. The aScope-2
has no suction port. Since outer diameter of the aScope-2(5.3 mm) is larger than that of adult reusable fiber-optic
scopes (3.5–4.2 mm), the Aintree Intubation Catheter, adevice specifically designed to aid fibrescope guided tube
placement through a laryngeal mask airway, cannot be usedwith it. When using a size 3 Aura-i laryngeal mask, amaximal ID size of the TT through this device is 6.5 mm.
Positive pressure ventilation may be difficult through combination of the 6.5 mm ID TT and the aScope-2 [17]. The
original technique needs the disconnection of the mountcatheter from Aura-i, the introduction of the aScope-2 into
the mask and then towards the trachea, followed by theintroduction of the tracheal tube through the aScope-2. The
variable time of apnea experienced during tracheal tube
positioning could become critical in situations where thepatient presents comorbidities that increase the risk related
to hypoventilation and/or hypoxia. As previously describedby Hammarskjöld et al. [18], conversion from laryngeal mask
to endotracheal tube may be difficult. In their paper, where
they intubated patients using a bougie guided techniquethrough a laryngeal mask with a fiber-optic bronchoscope,
the experienced time of apnoea was extremely variable: 17patients were intubated within 2 minutes, 11 patients wereintubated between 2 and 5 minutes, and one patient required
10 minutes. Variation of the intubation technique throughthe Aura-i laryngeal mask described in this case reportguarantees adequate ventilation during the entire procedureand could prevent this risk.

4. Conclusion
Applying positive pressure ventilation during fiber-optic
intubation through the SAD can reduce the potential risk ofhypoxia and hypercapnia in case of unanticipated difficult
airway.

ConsentWritten consent to publish this case report was obtaineddirectly from the patient described.

[1] American Society of Anesthesiologists Task Force on Management of the Difficult Airway, “Practice guidelines for management of the difficult airway: an updated report by the American
Society of Anesthesiologists Task Force on Management of theDifficult Airway,” Anaesthesiology, vol. 118, pp. 251–270, 2013.
[2] F. Petrini, A. Accorsi, E. Adrario et al., “Recommendationsfor airway control and difficult airway management,” Minerva
Anestesiologica, vol. 71, no. 11, pp. 617–657, 2005.
[3] A. Timmermann, “Supraglottic airways in difficult airway
management: successes, failures, use and misuse,” Anaesthesia,
vol. 66, no. 2, pp. 45–56, 2011.
[4] K. B. Greenland, H. Tan, and M. Edwards, “Intubation via
a laryngeal mask airway with an Aintree catheter—not all
laryngeal masks are the same,” Anaesthesia, vol. 62, no. 9, pp.
966–967, 2007.
[5] M. Carron, U. Freo, and C. Ori, “Bronchoscope-guided intubation through a laryngeal mask airway supreme in a patient witha difficult-to-manage airway,” Journal of Anesthesia, vol. 23, no.
4, pp. 613–615, 2009.
[6] P. Michalek, P. Hodgkinson, and W. Donaldson, “Fiberopticintubation through an I-Gel supraglottic airway in two patientswith predicted difficult airway and intellectual disability,” Anesthesia and Analgesia, vol. 106, no. 5, pp. 1501–1504, 2008.
[7] M. Weiss, A. C. Gerber, and A. Schmitz, “Continuous ventilation technique for laryngeal mask airway (LMA) removal after
fiberoptic intubation in children,” Paediatric Anaesthesia, vol.
14, no. 11, pp. 936–940, 2004.
[8] F. McAleavey and P. Michalek, “Aura-i laryngeal mask as aconduit for elective fibreoptic intubation,” Anaesthesia, vol. 65,no. 11, p. 1151, 2010.
[9] V. Krugel, I. Bathory, P. Frascarolo, and P. Schoettker, “Comparison of the single-use Ambu aScope 2 vs the conventional
fibrescope for tracheal intubation in patients with cervical spine
immobilisation by a semirigid collar,” Anaesthesia, vol. 68, no. 1,pp. 21–26, 2013.
[10] T. M. Cook and S. R. Macdougall-Davis, “Complications andfailure of airway management,” British Journal of Anaesthesia,
vol. 109, supplement 1, pp. i68–i85, 2012.
[11] A. Sinha, L. Jayaraman, D. Punhani, and B. Panigrahi, “ProSeal
laryngeal mask airway improves oxygenation when used as aconduit prior to laryngoscope guided intubation in bariatricpatients,” Indian Journal of Anaesthesia, vol. 57, no. 1, pp. 25–30,
2013.
[12] D. G. Mathew, R. Ramachandran, V. Rewari, A. Trikha, andChandralekha, “Endotracheal intubation with intubating laryngeal mask airway (ILMA), C- Trach , and Cobra PLA in
simulated cervical spine injury patients: a comparative study,”
Journal of Anesthesia, vol. 28, no. 5, pp. 655–661, 2014.
[13] J. A. Law, N. Broemling, R. M. Cooper et al., “The difficult
airway recommendations for management—part 2—the anticipated difficult airway,” Canadian Journal of Anesthesia, vol. 60,
no. 11, pp. 1119–1138, 2013.

4[14] D. T. Wong, J. J. Yang, H. Y. Mak, and N. Jagannathan, “Useof intubation introducers through a supraglottic airway tofacilitate tracheal intubation: a brief review,” Canadian Journalof Anesthesia, vol. 59, no. 7, pp. 704–715, 2012.
[15] P. Michalek, W. Donaldson, C. Graham, and J. D. Hinds, “Acomparison of the I-gel supraglottic airway as a conduit fortracheal intubation with the intubating laryngeal mask airway:
a manikin study,” Resuscitation, vol. 81, no. 1, pp. 74–77, 2010.
[16] T. Piepho, C. Werner, and R. R. Noppens, “Evaluation of thenovel, single-use, flexible aScope for tracheal intubation inthe simulated difficult airway and first clinical experiences,”
Anaesthesia, vol. 65, no. 8, pp. 820–825, 2010.
[17] K. Aoyama, E. Yasunaga, I. Takenaka, T. Kadoya, T. Sata, andA. Shigematsu, “Positive pressure ventilation during fibreoptic
intubation: comparison of the laryngeal mask airway, intubating laryngeal mask and endoscopy mask techniques,” British
Journal of Anaesthesia, vol. 88, no. 2, pp. 246–254, 2002.
[18] F. Hammarskjöld, G. Lindskog, and P. Blomqvist, “An alternative method to intubate with laryngeal mask and see-throughbougie,” Acta Anaesthesiologica Scandinavica, vol. 43, no. 6, pp.
634–636, 1999.

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