Effect of one-lung ventilation on pulmonary uptake of sevoflurane

Abstract

Objective To observe the effect of one-lung ventilation (OLV) or two-lung ventilation (TLV) on pulmonary uptake of sevoflurane.Methods Fifteen patients with esophageal tumorectomy and fifteen patients with stomach tumorectomy were selected for OLV and TLV during the operation,respectively.Sevoflurane was used for the general anesthesia.Bispectral index (BIS),Fi and Et were recorded at each measurement point,and Et/Fi was calculated.Results The BIS value of OLV group was higher than that of TLV group (P＜0.05),Et/Fi in OLV group was higher than TLV group (P＜0.01).OLV group:the BIS value gradually decreased and reached into an anesthetic state (BIS:60) at 5 min,and then enough anesthesia depth (BIS:40-60) was maintained during 5 min-120 min.Et gradually increased and reached into a steady state at 30 min.Et/Fi increased and reached into a steady state at 50 min,and the Et/Fi during 50 min-120 min had no statistical significance (P＞0.05).TLV group:the BIS value gradually decreased and reached into an anesthetic state at 2 min,and then enough anesthesia depth was maintained during 2 min-70 min.However,the BIS value was less than 40 after 70 min.Et gradually increased and reached into a steady state at 20 min.Et/Fi gradually increased and reached into a steady state at 2 min,and the Et/Fi during 2 min-120 min had no statistical significance (P＞0.05).Conclusions OLV had an effect on pulmonary uptake of sevoflurane.The total amount of sevoflurane uptake in OLV was less than that in TLV,while the uptake rate of OLV during 2 min-50 min was faster than that of TLV.Both OLV and TLV could supply a surgery-needed anesthetic depth with sevoflurane inhalant concentration 3％vol.However,inhalant concentration should be adjusted after 70 min to avoid excessive anesthesia during TLV.Furthermore,the anesthetic depth of OLV was less than that of TLV,and OLV needed a longer time to reach into a steady state compared with TLV. Key words: One-lung ventilation; Sevoflurane; Pulmonary uptake; Bispectral Index; Et