Intravenous Infusion of Dexmedetomidine Combined Isoflurane Inhalation Reduces Oxidative Stress and Potentiates Hypoxia Pulmonary Vasoconstriction during One-Lung Ventilation in Patients.
Inhalation anesthetic isoflurane inhibits hypoxia pulmonary vasoconstriction (HPV), while dexmedetomidine (Dex) could reduce the dose of isoflurane inhalation and potentiate HPV, but the mechanism is unclear. Inhibition of reactive oxygen species (ROS) production can favor HPV during one-lung ventilation (OLV). Similarly, nitric oxide (NO), an important endothelium-derived vasodilator in lung circulation, can decrease the regional pulmonary vascular resistance of ventilated lung and reduce intrapulmonary shunting. We hypothesized that Dex may augment HPV and improve oxygenation during OLV through inhibiting oxidative stress and increasing NO release. Patients undergoing OLV during elective thoracic surgery were randomly allocated to either isoflurane + saline (NISO, n = 24) or isoflurane + dexmedetomidine (DISO, n = 25) group. Anesthesia was maintained with intravenous remifentanil and inhalational isoflurane (1.0-2.0%), with concomitant infusion of dexmedetomidine 0.7 μgkg(-1)h(-1) in DISO and saline 0.25 mL kg(-1)h(-1) in NISO group. Hemodynamic variables or depth of anesthesia did not significantly differ between groups. Administration of Dex significantly reduced Qs/Qt and increased PaO2 after OLV, accompanied with reduced lipid peroxidation product malondialdehyde and higher levels of SOD activity as well as serum NO (all P < 0.05 DISO versus NISO). In conclusion, reducing oxidative stress and increasing NO release during OLV may represent a mechanism whereby Dex potentiates HPV.
Department of Anesthesiology, First Affiliated Hospital, Yangtze University, Jingzhou 434000, China.
Rui
R
Xia
Department of Anesthesiology, Wuhan University Renmin Hospital, Wuhan 430060, China.
Jinjin
J
Xu
Department of Anesthesiology, First Affiliated Hospital, Yangtze University, Jingzhou 434000, China.
Hong
H
Yin
Department of Cardiothoracic Surgery, Fifth Affiliated Hospital of Zunyi Medical College, Zhuhai 519100, China.
Huozhi
H
Wu
Department of Anesthesiology, The Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China ; Department of Anesthesiology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China ; Department of Anesthesiology, The University of Hong Kong, Hong Kong.
Zhengyuan
Z
Xia
Department of Anesthesiology, Guangdong No. 2 Provincial People's Hospital, Guangdong Provincial Emergency Hospital, Guangzhou, Guangdong 510317, China.
Daiwei
D
Zhou
Department of Anesthesiology, Wuhan University Renmin Hospital, Wuhan 430060, China.
Zhong-yuan
ZY
Xia
Department of Anesthesiology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China ; Department of Anesthesiology, The University of Hong Kong, Hong Kong.
Liangqing
L
Zhang
Department of Anesthesiology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China ; Department of Anesthesiology, The University of Hong Kong, Hong Kong.
Haobo
H
Li
Department of Anesthesiology, Guangdong No. 2 Provincial People's Hospital, Guangdong Provincial Emergency Hospital, Guangzhou, Guangdong 510317, China.
Xiaoshan
X
Xiao
D000328:Adult; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D020927:Dexmedetomidine / Q000008:administration & dosage* / Q000494:pharmacology*; D006801:Humans; D007262:Infusions, Intravenous; D007530:Isoflurane / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D061810:One-Lung Ventilation; D018384:Oxidative Stress / Q000187:drug effects*; D014661:Vasoconstriction / Q000502:physiology
D018685:Anesthetics, Inhalation; D020927:Dexmedetomidine; D007530:Isoflurane