THRIVETransnasal Humidified Rapid- Insufflation Ventilatory Exchange

A physiological method of increasing apnoea time in patients with difficult airways

Anaesthesia, 2014. Patel & NouraeiJoanna Gordon, ST7

Mechanisms of action

• Warmth & humidification allows higher flows

• Flush dead space in nasopharynx CO2

• Mechanical splinting supraglottic resistance

• Warmed, humidified – less constriction, more compliance

• Distending pressure – up to 6cm H2O pharyngeal pressure

• Apnoeic oxygenation

• Reducing rates of intubation in resp failure

• Reducing rates of re-intubation on ITU and PACU

• Home device as alternative to CPAP/BiPAP for OSA

& CLD

• Areas of increasing interest:

– Pre-oxygenation in high risk pts (adults)

– Oxygenation during difficult airway management

Uses

Sample

• Case series• 25 adult patients• Difficult airways - anatomical or rapid SpO2 likely• Stenosis, vocal fold pathology, OSA,

hypopharyngeal obstruction

Methods

• 40 degrees head up tilt• Optiflow at 70L/min, 10 minutes• Prop 2-3mg/kg, Fent 1-2μg/kg, Roc 0.5mg/kg

• TIVA maintenance, propofol 0.2-0.3mg/kg/min

• Jaw thrust on LOC• BMV confirmed then discontinued

1. MAC laryngoscopy2. VL 3. VL difficult blade

• Apnoea time = NMB to PPV or jet vent or SV

Results

• 15M, 10F• Mean age 49 (25-81)• Median BMI 30 (18-52)• 10 benign larynx, 2 OSA, 4 head & neck masses• 9 had stridor• Median MP = 3• Median C&L = 3• Mean apnoea time = 17mins (5 – 65)

Results

• Airway management:–14 suspension laryngoscopy with jet vent–4 ETT–4 LMA–2 THRIVE only–1 Tracheostomy

No SpO2 <90%

THRIVE

Limitations

• Observational & cross sectional – routine clinical care

• Optiflow only until definitive airway secured• Airway expert management ? generalisable• Techniques not far from our practice• Conclusion – can extend safe apnoeic window

THRIVE To change difficult airway management?