Total intravenous anaesthesia- Target Controlled Infusion and Superimposed High-Frequency Jet Ventilation – an anaesthetic protocol for interventional bronchoscopy in cancer patients

Abstract

Introduction: Diagnostic or therapeutic bronchoscopy may be performed under general anaesthesia in special circumstances aiming for patient safety and operator comfort. Tracheobronchial instrumentation requires an open system ventilatory support. We report the first case series of oncologic patients managed with Total Intravenous Anaesthesia–Target Controlled Infusion (TIVA-TCI) and Superimposed High-Frequency Jet Ventilation (SHFJV) during flexible and rigid bronchoscopy in our institution. We evaluated the safety profile of this technique in cancer patients. Methods: We analysed 24 oncological patients requiring bronchoscopy under general anaesthesia during a 9 months period. The anaesthetic protocol consisted in TIVA-TCI with propofol, Schnider model, site effect concentration, with standard intra-anaesthetic monitoring plus hypnosis and neuromuscular function monitoring and SHFJV using Twin StreamTM ventilator. Results: A number of 25 interventions were performed - 19 flexible and 6 rigid bronchoscopy. During the procedures, optimal anaesthesia depth (bispectral index=40-60) was maintained with a mean propofol site effect concentration Ce=3.1 (+/-0.6) µg/ml. Hemodynamic parameters varied +/-10-20% of preoperative values. SpO2 was stable with a mean value of 98.5% (FiO2=0.5-1) and intermittently measured etCO2 had a mean value of 32 (+/-5.4) mmHg. Airway pressures varied according to procedural particularities with a safety upper limit of 25 mmHg. We recorded no intra-anaesthetic or post-interventional complications. Conclusion: The anaesthetic protocol including TIVA-TCI and SHFJV is a safe and effective method of maintaining adequate depth of anaesthesia, cardiovascular stability and gas exchange during diagnostic or therapeutic bronchoscopy in cancer patients.