A 77-year-old woman was scheduled for aortic valve replacement because of severe aortic stenosis and the preoperative anesthesiological evaluation was suggestive for a possible difficult airway, as the patient was overweight (BMI 31.2 kg/m2), presented a Mallampati score of 3, a thyromental distance of 2.5cm, and mouth opening was 3cm. Furthermore, she referred history of difficult endotracheal intubation during two previous surgeries.

We planned elective intubation under fiberoptic guide and we administrated midazolam 5mg i.v. to reduce patient's anxiety and discomfort associated with awake intubation under fiberoptic guidance, and to maintain at the same time spontaneous breathing and collaboration for simple commands, such as coughing and breathing.

Baseline SpO2 was 97% in room air, and respiratory rate was 16 breaths/min.

We delivered CPAP (PEEP 5cmH2O) plus a pressure support of 10cmH2O through the new full-face “Janus” mask in order to support ventilation and maintain oxygenation.

After obtaining an Observer's Assessment of Alertness/Sedation scale score of 4 (lethargic response to name spoken in normal tone),5 an inexperienced anesthesiologist under expert supervision performed the procedure inserting the fiberoptic probe together with the endotracheal tube through the Janus mask central port into patient's mouth. The procedure was successful and uneventful, but required three attempts and lasted 12min.

The Janus mask was then removed simply separating its two halves, without compromising in any way the correct position and depth of the endotracheal tube. We then administered fentanyl (250mcg), propofol (150mg) and rocuronium (50mg), and set the mechanical ventilation for volume control continuous mechanical ventilation. Anesthesiological management and surgery were performed as usual and no complications were recorded. The procedure is also shown as a video in the supplementary material.

Two weeks later we treated another patient, a 69 year-old woman scheduled for thoracoabdominal aortic aneurysm repair surgery, with the same approach. On physical examination, the patient was overweight (BMI 33 kg/m2) and displayed a Mallampati score of 3, an interincisive distance of 4cm, loose inferior incisors, mandibular prognathism, and a reduced cervical spine range of motion. We programmed a Janus mask-aided elective awake fiberoptic intubation to manage this predicted difficult airway scenario. Baseline SpO2 was 98% in room air, and respiratory rate was 15 acts/min.

The patient received topical lidocaine, i.v. midazolam 2mg to reduce the discomfort associated with the procedure, and CPAP ventilation was started. An expert anesthesiologist performed the procedure in 5min. After the orotracheal intubation was successfully accomplished and confirmed, we induced general anesthesia with propofol i.v. 100mg, fentanyl 150mcg i.v., rocuronium 40mg i.v. The surgical operation was performed as planned.

We reported a new strategy to approach one of the worst scenarios that anesthesiologists may face, that is to say, the “planned difficult intubation” situation. Such strategy can also be extended to all the intensive care unit (ICU) patients and all acute critically ill patients, who are not intubated, need to undergo endoscopic procedures (fibroscopy, transesophageal echocardiography, etc.), and present nevertheless a reduced respiratory reserve or respiratory failure.6,7 In critically ill patients the intubation maneuver is hazardous due to factors related to the patients (hemodynamic instability, decreased oxygen and physiologic reserve, full stomach, coagulopathy, low platelet count, anticoagulants) and factors associated to the setting itself (inability of head extension, environment, attending physicians with variable levels of expertise in difficult intubation). Therefore the incidence of difficult intubation and the severity of desaturation is higher in ICU compared to the operating room.8 As a more profound desaturation is associated with higher risk of cardiac arrest,9 devices able to “gain time” during challenging intubation may improve outcome.

Janus mask applied during difficult airway management can significantly improve both pre-oxygenation and oxygenation during fibroscopic intubation maintaining an adequate oxygen saturation even in the event of prolonged or complex maneuvers. Although the pre-oxygenation is essential to avoid desaturation in the operating room, several authors have shown that it is not effective in ICU patients due to the coexistence of pulmonary and cardiac diseases, anemia, low cardiac output syndrome, sepsis, ventilation/perfusion mismatch, acute respiratory distress syndrome, pathologic states associated with increased consumption of oxygen.10,11 The rationale of the use of the Janus mask is supported also by the data from Miguel-Montanes,12 who observed a higher saturation at the end of pre-oxygenation in critical ill patients with mild to moderate respiratory failure with the use of a high flow nasal cannula oxygen (HFNO) compared to a non-rebreathing facemask. Several differences between HFNO and Janus mask have to be addressed: first, HFNO improves oxygenation “washing out” the pharyngeal deadspace with high oxygen concentration and a modest PEEP effect, while with Janus mask can be adopted increasing the end expiratory lung volume. Then, HFNO was not superior to facemask in improving oxygenation in patient with severe hypoxia who needed intubation,13 while Janus mask maintained an adequate oxygenation in fragile patients undergoing prolonged TEE for appendage closure, procedure which required more than an hour. Finally, although there is no experience with HFNO and fibroscopy in the context of difficult intubation, the possibility to perform the CPAP with Janus mask may maintain a better gas exchange during the entire procedure.

For all the reasons mentioned above we believe that the critical ill patients who may benefit from the use of this device are several in everyday clinical intensive care practice.

In addiction, the Janus mask may have a role in the training of junior colleagues with endoscopic maneuvers, as it supports ventilation and maintain oxygenation during the procedure. Therefore, long maneuvers can be tolerated, avoiding desaturation episodes.

We are aware that nowadays many simulation technologies are available and allow the acquisition of basic skills about fiberoptic intubation in a safe non-clinical scenario. However, the simulation is not fully representative of the real clinical life, which is often more complicated and stressful.

Furthermore, the Janus mask can be applied also during the endoscopy in case of oversedation or respiratory worsening of the patient, as it can be opened and then closed around the probe.

Other strategies do exist to perform intubation in a planned or unplanned difficult airway scenario and were reported in literature: overall, they involve the use of existing devices (laryngeal mask, videolaringoscopes, etc.) or tracheal puncture.14–18

Teteura and colleagues, for example, sperimented successfully Intubation Using a Double-lumen Tube with a Combination of Fiberoptic Bronchoscope and the Glidescope in a Patient with difficult airway,14 but this technique required the contemporary presence of 4 anesthesiologists, which is not generally possible in routine clinical practice (especially if the difficult airway situation is unexpected).

Furthermore, intubation with a videolaryngoscope requires a deep level of sedation, and eventually the administration of a neuromuscular blocking agents. Our strategy, on the contrary, can be performed also without curarization and with a mild/moderate level of sedation.

The I-gel laryngeal mask also proved to be a useful tool, when used in combination with a lightwand15 or the Aintree intubation catheter.16

Tracheal puncture at the level of the chricothyroid membrane to perform retrograde intubation17 and the use of a tracheal introducer18 were also reported as useful strategies in this context, but they are highly invasive.

In our opinion the use of such invasive approaches cannot be encouraged, now that modern, non-invasive, and safe devices such as the Janus mask are available. Furthermore, none of the previously reported strategies is able to support the spontaneous ventilation with a positive pressure during intubation maneuver.

In conclusion, we believe that the Janus mask may have an extraordinary potential in clinical practice. In particular, the use of this device has a strong rational as a bridge to awake fiberoptic intubation, as a rescue ventilator therapy during interventional procedures, and as an educational tool for the anesthesiologists without experience in fiberoptic intubation, who can improve their confidence with this procedure in a safe real life scenario.

MP: collection, analysis and interpretation of data, writing of the manuscript and final revision.

SS: study design, collection of data, writing of the manuscript and final revision.

CVD: study design, collection of data, writing of the manuscript and final revision.

GF: collection, analysis and interpretation of data, final revision of the manuscript.

AO: analysis and interpretation of data, final revision of the manuscript.

AZ: study design, collection and interpretation of data, final revision of the manuscript.

FM: study design, collection, analysis and interpretation of data, final revision of the manuscript.

The authors have no conflicts of interest concerning the publication of this manuscript. The study was supported by departmental funds. The founding sources had no role in the study design, collection, analysis and interpretation of data, and no role in the writing of the manuscript and the decision to submit it.