How to assess the adequate amount of air in an ET tube cuff
The authors of this clinical case report describe palpating the pilot
balloon to assess the pressure within the endotracheal tube cuff. This
technique has been reported elsewhere and the limitations of this
technique has been described (Briganti, Portela, Barsotti, Romano, &
Breghi, 2012; Veen & Grauw, 2022). Perhaps more sensitive techniques
such as auscultation over the larynx (Burns, 2020) or the use of
mechanical ventilation (Ferreira, Allen, De Gasperi, Buhr, & Morello,
2021) would be a better alternative. The latter is based on the fact a
mechanical ventilator will not cycle properly until there is an adequate
seal around the endotracheal tube cuff. Spirometry is another modality
that could be used for this purposed based upon this author’s clinical
experience in both small and large animal practice. In small animals, I
have detected differences between an unsealed and sealed endotracheal
tube cuff using as little as 0.2mL of air injected into the cuff based
upon the pressure-volume loop. Unfortunately, there is only one large
animal anaesthetic machine that has this capability11Tafonius,
Hallowell EMC, Pittsfield, MA 01201, USA. There is no current
consensus on the verification of the adequacy of a seal between the ET
tube cuff and tracheal wall.