Total intravenous anesthesia(TIVA) is desirable technique for a number of reasons. The first is that it implies all the components of general anesthesia: hypnosis, amnesia, analgesia, and muscle relaxation by combination of several drugs and the
lungs
are ventilated with oxygen-enriched air.
A combination of fentanyl-propofol were used as TIVA for laryngomicrosurgery (LMS) with high frequency jet ventilation(HFJV). 41 patients were studied. Glycopyrrolate was given 1 hour before anesthetic induction. Propofol 2 mg/kg was
intravenously
administered 1 minute after fentanyl 1.5 ug/kg intravenously injection for induction. Endotracheal intubation was performed after succinylcholine administration with internal diameter 4.0-6.0 mm LASER tube through oral cavity or 8 fr.
Polyethylene
catheter through nasal airway. After then, HFJV was started with frequency 108-120 cycles/minute and driving pressure 2.0-2.5 kg/cm². The adequacy of ventilation was evaluated with arterial blood gas analysis. For maintenance a continuous
propofol
infusion of 10 mg/kg/hour was used for the first 10 minutes, followed by 8 mg/kg/hour for the next 10 minutes and 6 mg/kg/hour, thereafter. Continuous dripping of succinylcholine was used for muscle relaxation.
The patients showed relatively stable hemodynamic status during procedure (Fig-1). Two recovery times were as followed: the interval from cessation of infusion until opening eyes on command(4.90±3.41 min), and that until correct response to
simple
question (5.50±3.49 min). There was a correlation between total amount of propofol given to patients and recovery times(P<0.05)(Table 1). Interestingly. A group of patients weighed over 70 kg showed carbon dioxide retension on arterial blood gas
analysis(Fig. 2).
In conclusion, fentanyl-propofol combination with muscle relaxant is proper regimen for TIVA in LMS with HFJV. More stable and better recovery are the main reasons. However, carbon dioxide retension should be consider to the patients weighed over
70 kg
with the HFJV.
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