Case presentation

A 68-year-old female patient with a body mass index of 31.2 kg/m² (height 160 cm; weight 80 kg) was planned for an elective incisional hernia repair under general anesthesia. Her underlying medical history included controlled type 2 diabetes mellitus, hypercholesterolemia (treated with atorvastatin), and mild persistent asthma (treated with salbutamol as needed). Additionally, she was a nonsmoker with no known drug allergies. Airway assessment was carried out preoperatively, which showed Mallampati Class II, clinically normal mouth opening, and unrestricted neck mobility; none of the standard criteria for predicted difficult intubation was met (Table 1).

Parameter | Finding/value
Mallampati classification | Class II: soft palate, major part of uvula and fauces visible
Thyromental distance | Grossly normal on clinical assessment
Interincisor gap | Clinically adequate mouth opening
Neck mobility | Full: unrestricted active flexion and extension
Body mass index | 31.2 kg/m² (Class I obesity)
Predicted difficult airway | No: standard assessment did not identify predictors of difficulty
ASA physical status | II: controlled type 2 diabetes, hypercholesterolemia, mild asthma

On directed questioning, the patient disclosed having received a general anesthetic around five years ago in Somalia for open cholecystectomy and reported that she experienced severe cough and throat pain that lasted for about 12 hours after the general anesthetic. No anesthetic records were available. The history was recorded but at first was not interpreted as being associated with structural airway difficulty, which became evident only during surgery.

Standard monitoring was used. The anesthetic induction drugs included midazolam 2 mg, fentanyl 150 μg, propofol 200 mg, and rocuronium 70 mg. Bag-mask ventilation was used to confirm appropriate mask seal and chest rise; ventilation was achievable with a proper seal around the facemask, though it required relatively high peak airway pressures of 28-32 cmH₂O with tidal volumes of 300-350 mL on the ventilator, and a normal capnograph waveform was present throughout.

Laryngoscopy with a video laryngoscope (McGrath blade, size 3) was performed by the primary anesthetist, which yielded a poor view (Cormack-Lehane Grade III, with only the epiglottis visible). With bimanual external laryngeal manipulation, the view improved to allow visualization of the arytenoids, but the vocal cords remained obscured. This was followed by advancing a gum-elastic bougie; direct visualization of glottic passage was not possible given the limited view. Hold-up was felt but was not relied upon as definitive confirmation of tracheal placement. A 7.5 mm endotracheal tube with a cuff was railroaded over the bougie but encountered subglottic resistance and failed to be advanced. Bag-mask ventilation was immediately restarted, and peripheral capillary oxygen saturation (SpO₂) was maintained between 97% and 99%.

Senior assistance was called in immediately, consistent with DAS 2025 guidance on early escalation within Plan A. A second attempt was made with a tube size 7.0 mm (by the primary anesthetist) over a newly inserted bougie, similarly failing at the subglottic resistance point. This bougie was left in situ following the failed attempt. The senior anesthetist arrived and proceeded with video laryngoscopy, using the previously placed bougie, which remained in tracheal position with hold-up (tracheal placement was not yet definitively confirmed at this stage). A 7.0 mm cuffed endotracheal tube was readvanced over this bougie to the point of subglottic resistance. Then, a deliberate rotational technique was performed: the tube was slowly rotated clockwise, then anticlockwise, while applying gentle concurrent axial pressure to make progressive advancement beyond the subglottic obstruction. Correct positioning was confirmed by continuous waveform capnography and bilateral chest auscultation. The overall time from induction to successful intubation was nine minutes, and SpO2 did not drop below 97%. Anesthesia was maintained with sevoflurane in oxygen-in-air, and the incisional hernia repair was carried out, lasting for 74 minutes without any bronchospasm and hemodynamic instability.

Following the completion of surgery, a sugammadex 200 mg (2.5 mg/kg) was injected intravenously. Extubation was performed in the semirecumbent position when the patient was fully awake, obeying instructions and with SpO₂ levels >97% on spontaneous ventilation. She awakened from anesthesia without complications, did not need any oxygen support after 20 minutes, and was moved to the surgical ward in stable condition. Prior to discharge from the hospital, she received both verbal and written difficult airway alerts, documented in the patient record.