VAFI and FARSI

OVERVIEW

Definitions

• VAFI is video-assisted flexible intubation, also termed FAVL or fiberoptic-assisted video laryngoscopy
• FARSI is flexiscope-assisted rapid sequence intubation
• Note that in clinical practice the terms flexiscope and flexible bronchoscopy are often used interchangeably with the older terminology of fiberoptic scope – most modern flexiscopes are not fiberoptic and use digital chip‑on‑tip cameras instead.

VAFI and FARSI are hybrid airway techniques that combine:

• Videolaryngoscopy (VL): airway exposure and creation of a pathway to the laryngeal inlet
• Flexible bronchoscopy (flexiscope): definitive navigation into and down the trachea. 

They were developed to address two distinct airway challenges:

• VAFI addresses difficulty reaching or traversing the vocal cords – supraglottic pathology – the videolaryngoscope is primarily a delivery tool for the scope, not necessarily a visualisation tool for the cords.
• FARSI address pathology below the cords (e.g. tracheal injury) – subglottic pathology – it designed to be fast and controlled, minimising airway manipulation

VAFI and FARSI are not substitutes for awake intubation when it is indicated.

USES

VAFI  is used for situations where awake intubation is not appropriate or infeasible (e.g. agitated, non-cooperative, or obtunded patients) AND either:

• Anticipated difficult intubation due to difficulty getting to or through the cords, e.g.
  • Anterior larynx
  • Crowded pharynx (loss of view when introducing tube)
  • Obstructing or friable supraglottic lesions
• Failed intubation due to:
  • VL alone fails (poor view and/or can’t pass tube)
  • Flexiscopy alone is difficult (unable to navigate to vocal cords)

FARSI is used for situations requiring rapid sequence intubation with controlled tube placement below the vocal cords

• Trauma (e.g. hanging, blunt/penetrating injury) with:
  • suspected or confirmed tracheal disruption
  • risk of false passage or worsening tracheal tear

DESCRIPTION

VAFI

• VL is inserted to:
  • displace soft tissues
  • open the airway
  • create a pathway to the laryngeal inlet
• A flexible bronchoscope (with preloaded ETT) is used as a steerable bougie that:
  • identifies the vocal cords
  • advances into the trachea
  • guides tube placement

FARSI

• Performed as a standard RSI until ETT reaches the level of the cords
• The tube is then paused at the glottis
• A flexiscope is passed:
  • through the tube
  • beyond any tracheal disruption
• Tube is advanced using a “railroading” technique over the flexiscope

METHOD OF INSERTION/ USE

VAFI

• Insert videolaryngoscope and perform laryngoscopy
  • optimise space, not necessarily view
  • hyperangulated blade preferred
• Introduce flexiscope with ETT preloaded
  • advance alongside VL blade
  • VL maintains space for flexiscope delivery
• Identify vocal cords using flexiscope
• Advance flexiscope into trachea
  • Confirm endotracheal location by identification of tracheal rings, trachealis muscle, and carina
• Railroad ETT over scope
  • Once ETT positioned, remove flexiscope while stabilising the ETT
• Confirm placement
  • bronchoscope view (and secondary confirmation with VL view)
  • ETCO₂
• Secure the ETT

Video demonstration of VAFI by Cliff Reid and the Sydney HEMS team:

FARSI

• Prepare for RSI (preoxygenate, optimise patient position, ensure team and equipment readiness)
• Perform rapid induction and paralysis
  • Administer RSI drugs (e.g. thiopentone and suxamethonium)
  • Avoid positive‑pressure ventilation unless required to prevent or correct significant  hypoxaemia
  • Maintain manual in‑line stabilisation if indicated
• Perform laryngoscopy
  • Suction airway if needed
  • Identify laryngeal inlet and vocal cords
  • Insert ETT to laryngeal inlet, but do not advance distal tip beyond the vocal cords
• Introduce the flexiscope through the ETT into the trachea
  • Confirm endotracheal location by identification of tracheal rings, trachealis muscle, and carina
  • Inspect trachea for trauma (e.g. tracheal ring disruption or false passage)
  • Advance bronchoscope to the carina for definitive confirmation
• Railroad ETT over scope
  • Ensure bevel orientation avoids mucosal injury
  • Once ETT positioned, remove flexiscope while stabilising the ETT
• Confirm placement
  • bronchoscope view (and secondary confirmation with VL view)
  • ETCO₂
• Secure the ETT

CONTRA-INDICATIONS

• Situations where awake intubation is indicated (e.g. suspected or known difficult airway in a cooperative patient)

VAFI

• Extremely limited access (e.g. severe trismus) preventing use of a laryngoscope
• Inability to pass bronchoscope (e.g. gross contamination, severe bleeding)

FARSI

• No suspicion of tracheal injury (no added benefit over standard RSI)
• RSI not required (e.g. fasted and negligible risk of aspiration)

COMPLICATIONS

General

• Failed intubation
• Loss of airway control
• Hypoxia
• Airway trauma

VAFI specific risks

• Bronchoscope obscured by blood/secretions
• Tube impingement during railroading

FARSI specific risks

• Creation of false passage
• Worsening tracheal disruption
• Subcutaneous emphysema if ventilation before cuff inflation

OTHER INFORMATION

Tips and traps

• When performing VAFI watch the VL screen when advancing the flexiscope to the laryngeal inlet, then watch the flexiscope screen when advancing through and beyond the vocal cords.
• Rotate the bevel of the ETT anticlockwise when advancing through the laryngeal inlet over a flexiscope to avoid hang up or injury at the arytenoids
• Once through the vocal rotate the ETT back if anterior tracheal injury is suspected to decrease the risk of the ETT hanging up on, and extending, a tracheal tear

VAFI versus FARSI comparison

Feature	VAFI	FARSI
Problem	Above cords	Below cords
ETT  preloaded on flexiscope	Yes	No
Timing	Controlled	Rapid
Purpose	Facilitate passage of flexiscope to laryngeal inlet	Facilitate safe passage below the laryngeal inlet and beyond site of injury

See also the video of Adam Rehak’s talk on VAFI and FARSI from the 2022 Safe Airway Society meeting:

REFERENCES AND LINKS

Journal articles

• Gunasekaran K, Joshi R, Karunagaran P, Yachendra VSG. A Hybrid Technique Using Video Laryngoscope-assisted Flexible Bronchoscopy to Facilitate Endotracheal Intubation in Children with Anticipated Difficult Airway: A Case Series. Turk J Anaesthesiol Reanim. 2025 Mar 21;53(2):77-81. doi: 10.4274/TJAR.2024.241587. PMID: 40116470; PMCID: PMC11931264.
• Lenhardt R, Burkhart MT, Brock GN, Kanchi-Kandadai S, Sharma R, Akça O. Is video laryngoscope-assisted flexible tracheoscope intubation feasible for patients with predicted difficult airway? A prospective, randomized clinical trial. Anesth Analg. 2014 Jun;118(6):1259-65. doi: 10.1213/ANE.0000000000000220. Erratum in: Anesth Analg. 2015 Feb;120(2):495. PMID: 24842175.
• Mercer SJ, Lewis SE, Wilson SJ, Groom P, Mahoney PF. Creating airway management guidelines for casualties with penetrating airway injuries. J R Army Med Corps. 2010 Dec;156(4 Suppl 1):355-60. doi: 10.1136/jramc-156-04s-15. PMID: 21302656.
• Mercer SJ, Jones CP, Bridge M, Clitheroe E, Morton B, Groom P. Systematic review of the anaesthetic management of non-iatrogenic acute adult airway trauma. Br J Anaesth. 2016 Sep;117 Suppl 1:i49-i59. doi: 10.1093/bja/aew193. PMID: 27566791.
• Reddy A, Bansal R, Kaloria N, Patel S, Gowda PK. Utility of the Awake Video Laryngoscopy Assisted Fibreoptic Intubation Technique in Maxillofacial Gunshot Injury – A Case Report. Ann Maxillofac Surg. 2023 Jan-Jun;13(1):120-122. doi: 10.4103/ams.ams_31_23. Epub 2023 Jul 25. PMID: 37711543; PMCID: PMC10499282.
• Saunders TG, Gibbins ML, Seller CA, Kelly FE, Cook TM. Videolaryngoscope-assisted flexible intubation tracheal tube exchange in a patient with a difficult airway. Anaesth Rep. 2019 Apr 11;7(1):22-25. doi: 10.1002/anr3.12007. PMID: 32051940; PMCID: PMC6931294.

FOAM and web resources

• Airway Innovators 2 – VAFI and FARSI (Adam Rehak): https://www.youtube.com/watch?v=Qw6FB29rSf4 (12 min video) 
• The Protected Airway – Learn Fiberoptic-assisted Video Laryngoscopy (FAVL)