BACKGROUND: High frequency jet ventilation (HFJV) via thin tracheal tube is a convenient method of ventilation in microlaryngosurgery, but the problem of the assessment of oxygen and carbon dioxide status during HFJV is yet to be studied. METHODS: Fifteen patients undergoing microlaryngosurgery under total intravenous anesthesia with HFJV were studied. The combined transcutaneous carbon dioxide (PtcCO2) and oxygen (PtcO2) levels were compared with arterial blood gas values (PaCO2, PaO2). RESULTS: The PtcCO2 values demonstrated a high degree of correlation with PaCO2 before intubation (r = 0.97), during HFJV (r = 0.96), and after anesthesia (r = 0.93). The PaO2 values demonstrated a generally good correlation with PaO2 before intubation (r = 0.78) and during HFJV (r = 0.83), but not after anesthesia (r = 0.54). CONCLUSION: Capnography values are invalid during HFJV, and an arterial catheter is not always indicated and feasible in microlaryngoscopy. The transcutaneous devices provide an effective method for non-invasive monitoring of PaCO2 in situations where continuous and precise control of CO2 levels is desired such as in perioperative period of microlaryngosurgery with HFJV.
BACKGROUND: High frequency jet ventilation (HFJV) via thin tracheal tube is a convenient method of ventilation in microlaryngosurgery, but the problem of the assessment of oxygen and carbon dioxide status during HFJV is yet to be studied. METHODS: Fifteen patients undergoing microlaryngosurgery under total intravenous anesthesia with HFJV were studied. The combined transcutaneous carbon dioxide (PtcCO2) and oxygen (PtcO2) levels were compared with arterial blood gas values (PaCO2, PaO2). RESULTS: The PtcCO2 values demonstrated a high degree of correlation with PaCO2 before intubation (r = 0.97), during HFJV (r = 0.96), and after anesthesia (r = 0.93). The PaO2 values demonstrated a generally good correlation with PaO2 before intubation (r = 0.78) and during HFJV (r = 0.83), but not after anesthesia (r = 0.54). CONCLUSION: Capnography values are invalid during HFJV, and an arterial catheter is not always indicated and feasible in microlaryngoscopy. The transcutaneous devices provide an effective method for non-invasive monitoring of PaCO2 in situations where continuous and precise control of CO2 levels is desired such as in perioperative period of microlaryngosurgery with HFJV.