VL, SGA, FOB, lung isolation, cricothyroidotomy, exchange catheter, jet ventilation
Stem
Airway scenario (illustrative; the ABA has not published this station's format). A 66-year-old man, 82 kg, 178 cm, with prior neck radiation and a documented difficult airway, has just been intubated awake with a flexible bronchoscope using an 8.0 single-lumen tube. He needs a left upper lobectomy by thoracoscopy, so the surgeon asks for left lung isolation. A videolaryngoscope, bronchial blocker, left double-lumen tubes and a long exchange catheter are on the cart.
Question
How will you isolate his left lung, and why that device?
Ideal answer
HeadlineI will not lose an airway I have just secured: a bronchial blocker through the existing single-lumen tube, because blockers go through a tube already in place.1
- Blocker through the multiport adapter beside the bronchoscope. I steer it into the left main bronchus under direct vision.
- Balloon just below the carina, seen before and after turning. He goes lateral, and a blocker dislodges easily, so it is deflated during positioning and rechecked with the scope.
- Know its limits. No suction or lavage of the isolated lung through it, and trials conflict on how fast the lung collapses.1
- DLT needed: exchange over a ≥83 cm catheter.1 A videolaryngoscope lifts the tissues and guides the tube; 41 French left-sided, since he is taller than 170 cm.2
- Confirm any device with the bronchoscope. Auscultation is not enough.1
Breaking down the answer
The 2027 outline lists every device below, from laryngoscopy to jet ventilation, under airway management.3 The ABA has announced only that a 2027 unscored pilot station may test airway management; how devices will be presented has not been published.4
| Device | When I reach for it | The step that is graded |
|---|---|---|
| Videolaryngoscope | Predicted or encountered difficult laryngoscopy | Better views and first-pass success in difficult airways;5 angulated blades need a shaped stylet or bougie6 |
| Second-generation SGA | Rescue oxygenation, Plan B | Maximum three attempts; remove cricoid pressure to place it6 |
| Intubation through an SGA | Oxygenating via SGA, tube still needed | Use a flexible scope, not blind passage5 |
| Flexible bronchoscope | Awake intubation; confirming DLT or blocker position | See the carina before advancing the tube |
| DLT or bronchial blocker | Lung isolation | Bronchoscopic confirmation1 |
| Airway exchange catheter | Tube change or staged extubation | 92% success in staged difficult extubation5 |
| Cricothyroidotomy | Can't intubate, can't oxygenate | Scalpel, bougie, 6.0 cuffed tube;6 vertical skin incision by default unless the membrane is clearly palpable or ultrasound-marked7 |
| Jet ventilation | Narrow-bore access only | High-pressure source; barotrauma risk6 |
- Why left-sided — the right upper lobe takeoff makes a right tube harder to seat.1
- Combine before abandoning — a videolaryngoscope plus a flexible bronchoscope achieves higher first-attempt success than the videolaryngoscope alone.5
- A wide cuffed tube beats a cannula — it protects against aspiration, lets him exhale, allows ventilation with a standard circuit and gives a capnogram, which is why scalpel cricothyroidotomy is the DAS default.6
- Blind SGA intubation is outdated — DAS calls blind techniques through a supraglottic airway not recommended.6
- Know the exchange catheter's harms — misplacement into the esophagus and intolerable cough are reported.5
Follow-up question
At the end of the case you extubate over a staged airway exchange catheter, which he tolerates. Fifteen minutes later he develops stridor and his saturation falls to 85% despite face-mask oxygen. What do you do?
Follow-up answer
HeadlineFailed extubation in a known difficult airway; I call for help and the airway cart now.
Oxygen, then reintubation over the catheter still in place: a smaller tube railroaded over it, a videolaryngoscope lifting the tongue so the tube does not catch on the arytenoids,6 and capnography to confirm.5 Jet ventilation through the catheter only as a last resort, because high-pressure oxygen through a narrow lumen carries a serious risk of barotrauma.6 If the catheter is out and mask or supraglottic airway cannot oxygenate, I declare can't intubate, can't oxygenate and perform a scalpel cricothyroidotomy.6 Then I find the cause of the stridor, edema or a hematoma, before the next extubation.
Pitfalls that cost points
- Pulling the hard-won 8.0 tube to place a double-lumen tube without exchanging over a catheter.
- Pulling the exchange catheter before the airway has proved itself.
Rapid-fire
Q: DLT size for a woman 158 cm tall? A: Usually 35 French; taller women often take 37.1
Q: When is a right-sided DLT indicated? A: For left pneumonectomy or surgery on the proximal left main bronchus.1
Q: What color is the bronchial cuff? A: Blue.1
Q: Which scalpel blade for cricothyroidotomy? A: A number 10, broad enough to admit the tube.6
Q: What does transtracheal jet ventilation achieve? A: In one retrospective study it restored saturation above 90%, but evidence is limited.5
Numbers to know
| Item | Value |
|---|---|
| DLT, men | 39 Fr under 170 cm; 41 Fr if taller2 |
| DLT, women | 35 Fr under 160 cm; 37 Fr if taller2 |
| Exchange catheter for DLT | ≥83 cm1 |
| Staged extubation success | 92%5 |
| SGA attempts | Maximum 36 |
| Surgical airway tube | 6.0 mm cuffed6 |
Links
- Airway station: exam, algorithm, device choice (2027), Double-lumen tubes and bronchial blockers, Anticipated difficult airway and the ASA algorithm, Cannot intubate, cannot oxygenate, Awake fiberoptic intubation: topicalization and sedation
- Atlas: Airway ultrasound structures (2027); Tracheostomy, laser surgery and jet ventilation
- ASA Practice Guidelines for Management of the Difficult Airway (2022); DAS unanticipated difficult intubation guideline (2015)
Sources
- 1.Lung Isolation Anesthesia · StatPearls · statpearls.com
- 2.Deciding how to decide the correct double-lumen tube: a narrative review of methods and evidence · Journal of Anesthesia, Analgesia and Critical Care (Rispoli et al.), 2025 · europepmc.orgHeight-and-sex rule (Slinger): women under 160 cm 35 Fr, taller 37 Fr (32 Fr under 150 cm); men under 170 cm 39 Fr, taller 41 Fr (37 Fr under 160 cm).
- 3.APPLIED Exam Objective Structured Clinical Examination (OSCE) Content Outline · ABA · theaba.orgSection B.4, Airway Management (testing to start 2027): device list.
- 4.ABA Announces 8th OSCE Station Pilot for 2027 APPLIED Exams · ABA, 2026 · theaba.orgUnscored pilot; airway management or team-based scenario. Format and equipment not published.
- 5.2022 American Society of Anesthesiologists Practice Guidelines for Management of the Difficult Airway · ASA, 2022 · asa2.silverchair.com
- 6.Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults · DAS, 2015 · ebi.ac.ukFull text via Europe PMC (PMC4650961).
- 7.Difficult Airway Society 2025 guidelines for management of unanticipated difficult tracheal intubation in adults · DAS, 2025 · sea.org.ecAhmad et al., Br J Anaesth 2026;136:283-307 (online 7 Nov 2025), doi 10.1016/j.bja.2025.10.006; full English text hosted by the Sociedad Ecuatoriana de Anestesiología. Plan D: vertical skin incision (up to 8 cm) is the default eFONA incision unless the cricothyroid membrane is clearly palpable or ultrasound-marked; number 10 blade, bougie, 6.0 cuffed tube.
Facts on this page were checked against these sources on Oct 15, 2026. Guidelines change; confirm doses against current institutional protocols.