The role of halogenated inhalation anesthetics in the organization of gas exchange function of the lungs in thoracic surgery

Abstract

Introduction: Impact on pulmonary gas exchange during anesthesia occurs not only due to respiratory technologies, but the influence of inhalation anesthetics.

Objective: To assess the effect of inhalation anesthetics (desflurane, sevoflurane) on gas exchange during thoracic operations under conditions of artificial one-lung ventilation (OLV).

Materials and methods: 37 patients were studied. General anesthesia was performed with OLV, the main hypnotic component: desflurane (DF) - 23 patients, sevoflurane (SF) - 14 patients. We analyzed the indicators of systemic, pulmonary, intracardiac hemodynamics (Swan-Ganz), gas exchange and metabolism of arterial and mixed venous blood. Research stages: Stage 1 - after anesthesia induction, two-lung ventilation; Stage 2 - OLV 30 minutes; 3 and 4 stages - OLV 60 and 80-120 minutes respectively; Stage 5 - 30 minutes after two-lung ventilation restart.

Results: The severity of changes in systemic, pulmonary hemodynamics and gas exchange, as well as pre- and postcapillary resistances (Ra, Rv) in the DF and SF groups didn’t have significant differences. Significantly lower total peripheral resistance of DF from SF at stages 3 and 4 of OLV, a better indicator of the pumping ratio of the right ventricle (RVPR) and physiological dead space (VD) in the DF group at all stages of the study were noted.

Conclusion: In the conditions of OLV, DF shows a marked vasodilating effect, which extends to the reserve regions of gas exchange blood flow in the lungs: bronchial and bronchopulmonary blood flows, vessels of extracapillary diffusion, which are vessels of systemic blood flow. This, in turn, provides a higher RVPR.