Effects of tubeless superimposed high frequency jet ventilation on haemodynamic response and oxygenation in rigid bronchoscopy

Effects of tubeless superimposed high frequency jet ventilation on haemodynamic response and oxygenation in rigid bronchoscopyThe aim of this study is to investigate the effects of tubeless superimposed high frequency jet (SHFJV) ventilation on hemodynamic parameters and oxygenation in rigid bronchoscopy and compare with the conventional ventilation. ASA I-II 40 patients were randomly assigned to two equal groups. After patients received 1 mg/kg iv lidocaine, 2-2.5 mg/kg propofol, 0.6 mg/kg rocuronium, 0.2 µg/kg/min remifentanil, anesthesia was maintained using total intravenous anesthesia with propofol (4-10 mg/kg/h) propofol and remifentanil (0.05-0.2 µg/kg/min). Group I was ventilated with the conventional ventilation and Group II was ventilated with SHFJV. Superimposed high frequency jet ventilation?s normal frequency unit was set at 12 breath/min, I:E ratio=1:2; and high frequency unit at 600/min, I:E ratio=1:2. Heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure, peripheric oxygen saturation (SpO2), end tidal carbondioxide (ETCO2) levels, PaO2, PaCO2, pH, SO2, HCO3, peak inspiratory pressure (PIP), mean airway pressure and PEEP values were recorded at onset (control), induction, before, during and after bronchoscopy and postoperative first hour. SAP was found significant low at the 10th min in Group II (p<0.05). No significant difference was observed for SpO2 and PaO2 between the two groups. In SHFJV group, ETCO2 and PaCO2 values were lower (p<0.05), PEEP and MAP were found higher than the conventional group. Consequently, the model of SHFJV may increase PEEP and MAP. In conclusion, because of the advantage of achieving more effective CO2 elimination as well as hemodynamic stability and sufficient oxygenation, SHFJV should be prefered for rigid bronchoscopy.