Transnasal Humidified Rapid‐Insufflation Ventilatory Exchange (THRIVE): a physiological method of increasing apnoea time in patients with difficult airways

Abstract

Emergency and difficult tracheal intubations are hazardous undertakings where successive laryngoscopy–hypoxaemia–re-oxygenation cycles can escalate to airway loss and the ‘can't intubate, can't ventilate’ scenario. Between 2013 and 2014, we extended the apnoea times of 25 patients with difficult airways who were undergoing general anaesthesia for hypopharyngeal or laryngotracheal surgery. This was achieved through continuous delivery of transnasal high-flow humidified oxygen, initially to provide pre-oxygenation, and continuing as post-oxygenation during intravenous induction of anaesthesia and neuromuscular blockade until a definitive airway was secured. Apnoea time commenced at administration of neuromuscular blockade and ended with commencement of jet ventilation, positive-pressure ventilation or recommencement of spontaneous ventilation. During this time, upper airway patency was maintained with jaw-thrust. Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) was used in 15 males and 10 females. Mean (SD [range]) age at treatment was 49 (15 [25–81]) years. The median (IQR [range]) Mallampati grade was 3 (2–3 [2–4]) and direct laryngoscopy grade was 3 (3–3 [2–4]). There were 12 obese patients and nine patients were stridulous. The median (IQR [range]) apnoea time was 14 (9–19 [5–65]) min. No patient experienced arterial desaturation < 90%. Mean (SD [range]) post-apnoea end-tidal (and in four patients, arterial) carbon dioxide level was 7.8 (2.4 [4.9–15.3]) kPa. The rate of increase in end-tidal carbon dioxide was 0.15 kPa.min−1. We conclude that THRIVE combines the benefits of ‘classical’ apnoeic oxygenation with continuous positive airway pressure and gaseous exchange through flow-dependent deadspace flushing. It has the potential to transform the practice of anaesthesia by changing the nature of securing a definitive airway in emergency and difficult intubations from a pressured stop–start process to a smooth and unhurried undertaking.

Intra‐oral ignition of monopolar diathermy during transnasal humidified rapid‐insufflation ventilatory exchange (THRIVE)

“…At our institution, we use HFNO to deliver a lower F I O 2 during laser airway surgery. However, here we used HFNO to provide 100% oxygen in a spontaneously breathing, sedated, obese patient to prevent desaturation in the event of apnoea from over-sedation [5]. With the benefit of hindsight, an air/oxygen mixture could have been used to reduce, but not eliminate [6], the risk of airway fire.…”

Nasal high flow therapy: a novel treatment rather than a more expensive oxygen device

“…Even without lung expansion, oxygen diffusion from the alveoli to the capillaries decreases alveolar pressure, and by increasing pharyngeal oxygen content a flow of air is generated from the pharynx to the distal airway, which is called apnoeic oxygenation [61]. High flow rates with NHF create a great oxygen reservoir in nasopharyngeal area, which together with carbon dioxide elimination by flushing of the dead space [11,12] and the generated CPAP [3][4][5][6][7][8] make NHF a promising oxygenation device in the peri-intubation period, which maintains oxygenation without a rapid and dangerous rise in carbon dioxide concentration [62].…”

Obstructing pathology of the upper airway in a post-NAP4 world: time to wake up to its optimal management

“…This includes equipment for primary and alternative intubation techniques, a supraglottic airway sized for the patient, attention to preoxygenation, and delivery of apneic oxygenation during attempts at laryngoscopy and tracheal intubation. 27,28 As always, the CTM should be identified and marked, equipment for emergency surgical airway should be available, and there should be an individual designated to proceed rapidly with a surgical airway, if required.…”