[Relationship between driving pressure and tidal volume during high frequency jet ventilation for the tracheal resection].

ABSTRACT

BACKGROUND: High frequency jet ventilation (HFJV) is a method of ventilation for tracheal resection because it provides a good surgical field and decreases surgical complications. We should know ventilatory settings of HFJV to perform safe respiratory management. In this study we evaluated the relationship between tidal volume (VT) and driving pressure (DP) during HFJV for tracheal resection. METHODS: Twenty patients undergoing tracheal resection under total intravenous anesthesia were studied. Jet pulse was delivered through a 12 or 15 Fr feeding catheter connected to a jet ventilator. We set DP optionally and inspired oxygen concentration 100%, ventilatory frequency 100 x min(-1), and I/T ratio 0.3 or 0.5. In fourteen patients receiving HFJV with 15 Fr catheter we calculated VT by measured PaCO2, reported VCO2 value, and physiological dead space (1.1 x body weight) for each patient and evaluated relationship between VT and DP. RESULTS: HFJV was feasible in all patients. Pneumothrax occurred in one patient. Respiratory complications including pneumonia and respiratory failure were not observed after surgery in all patients. The calculated VT values showed a significant correlation with DP (VT = 48.1 DP + 44.7, r=0.73, P<0.01). CONCLUSIONS: In respiratory management for tracheal resection with HFJV, we can predict DP from VT calculated by expected PaCO2, reported VCO2 value, and physiological dead space. It enables us to perform safe respiratory management.