Influence of Tracheal Obstruction on the Efficacy of Superimposed High-frequency Jet Ventilation and Single-frequency Jet Ventilation
2015 (English)In: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175, Vol. 123, no 10, 799-809 p., doi:10.1097/ALN.0000000000000818Article in journal (Refereed) Published
Superimposed high frequency jet ventilation (SHFJV) has been used successfully in selected patients with severe central airway obstruction undergoing airway interventions.
We sought to systematically describe the efficacy of SHFJV in relation to obstruction and the high frequency component (fHF) in a model of tracheal stenosis.
Ten anesthetized animals (25-31.5kg) were alternately ventilated with SHFJV (low frequency 16min-1, random fHF) at a set of different fHF from 50-600min-1. Tracheal obstruction was created using exchangeable stents with different inner diameter (2, 4, 6, 8mm) that were inserted into the trachea. Chest wall volume was measured using optoelectronic plethysmography, airway pressures were recorded and blood gases were analyzed repeatedly.
Stent ID reduction from 8 to 2mm resulted in an increase of ∆EEVCW by up to 3x (e.g. 323 [255 - 410] ml vs 106 [81 - 138] ml at fHF=100 min-1). At the same time, VT decreased by up to 4.2x (e.g. 477 [434 – 524] ml vs 114 [79 – 165] ml). PaO2 and paCO2 remained at acceptable levels for 4-8 mm stent ID but CO2 removal became suddenly impaired at 2mm stent ID (paCO2>12 kPa). Pre-stenotic airway pressure monitoring was accurate at 8mm stent ID, but overestimation of peak inspiratory pressure (PIP) up to 2x and underestimation of PEEP up to 19x was observed at 2mm stent ID.
SHFJV was able to maintain oxygenation and carbon dioxide removal over a wide range of obstructions, despite decreasing VT and successive air trapping. At 2 mm stent ID, only carbon dioxide removal became insufficient.
Place, publisher, year, edition, pages
2015. Vol. 123, no 10, 799-809 p., doi:10.1097/ALN.0000000000000818
jet ventilation, airway obstruction, tracheal stenosis, HFJV, SHFJV
Anesthesiology and Intensive Care
Research subject Anaesthesiology and Intensive Care
IdentifiersURN: urn:nbn:se:uu:diva-229061OAI: oai:DiVA.org:uu-229061DiVA: diva2:735506
FunderSwedish Research CouncilSwedish Heart Lung Foundation