A comparative study of the effect of halothane, isoflurane and propofol on partial arterial oxygen pressure during one-lung ventilation in thoracic surgery.

BACKGROUND

Conducting one lung ventilation (OLV) in thoracic surgery highlights the issue of the onset (prevention and treatment) of clinically significant arrhythmogenic hypoxemia. The halogenated volatile anaesthetics are the drugs of choice in thoracic surgery despite the numerous experimental data showing their inhibiting effect on the hypoxic pulmonary vasoconstriction (HPV). The intravenous anaesthetic agent propofol has not been shown to influence this reflex mechanism. The object of the present study was to compare in clinical conditions the arterial oxygenation in patients undergoing noncardiac thoracic procedures, requiring a period of one lung ventilation during general anaesthesia with volatile anaesthetics halothane, isoflurane and total intravenous anaesthesia (TIVA) with propofol/fentanyl.

MATERIAL AND METHODS

The study included 45 patients divided in three groups consisting of 15 anaesthetized subjects each: group A--halothane; group B--isoflurane and group C--propofol/fentanyl. Arterial blood samples for blood-gas analysis were taken as follows: first probe (T1)--after two lung ventilation (TLV) was maintained for 15 min., second probe (T2)--after 45 min. of stable OLV and the third probe (T3)--during wound closure. The changes in PaO2 were statistically analyzed using the methods of descriptive and dispersion analyses.

RESULTS

A significant decrease in PaO2 during stable OLV compared with TLV (P < 0.05) was found in patients of all three groups. There was no significant difference in PaO2 between the subjects in the three groups during respective regimens of ventilation.

CONCLUSION

TIVA with propofol/fentanyl can be successfully applied in thoracic surgery as an alternative of general anaesthesia with halogenated volatile anaesthetics.