Opposing effects of isoflurane and sevoflurane on neurogenic pulmonary edema development in an animal model.
BACKGROUND
The current study was undertaken to investigate the effects of pretreatment with isoflurane and sevoflurane on the development of neurogenic pulmonary edema in an animal model.


METHODS
Rats were exposed to room air (control), 1.5% isoflurane, or 2.5% sevoflurane for 4 h. They were then anesthetized with intraperitoneal injections of pentobarbital sodium, and fibrinogen and thrombin were injected into the cisterna magna to induce neurogenic pulmonary edema.


RESULTS
Consecutive injections of fibrinogen and thrombin caused increases in blood pressure, with the peak values obtained in the isoflurane and sevoflurane groups being lower than the control values. The incidence of significant neurogenic pulmonary edema was 58%, 100%, and 8% in the control, isoflurane, and sevoflurane groups, respectively. The lung water ratio, an index of severity of edema, was 4.86 +/- 0.78, 6.15 +/- 0.64, and 4.40 +/- 0.32 in the control, isoflurane, and sevoflurane groups, respectively. Furthermore, immunohistochemical staining for vascular endothelial growth factor demonstrated an increase of expression in the rat lungs exposed to isoflurane. Treatment with an anti-vascular endothelial growth factor antibody during exposure to isoflurane completely inhibited the effect of isoflurane to promote neurogenic pulmonary edema in this model.


CONCLUSIONS
Exposure to 1.5% isoflurane enhances the development of neurogenic pulmonary edema development in this animal model, most likely via release of vascular endothelial growth factor from bronchial epithelial cells, an effect not observed with sevoflurane.
Kandatsu
Nobuhisa
N
Aichi Medical University, Nagakute-cho, Aichi-gun, Aichi Prefecture, Japan.
Nan
Yong-Shan
YS
Feng
Guo-Gang
GG
Nishiwaki
Kimitoshi
K
Hirokawa
Mitsuru
M
Ishikawa
Kiyonori
K
Komatsu
Toru
T
Yokochi
Takashi
T
Shimada
Yasuhiro
Y
Ishikawa
Naohisa
N
D000818:Animals; D002478:Cells, Cultured; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D007530:Isoflurane / Q000008:administration & dosage / Q000633:toxicity*; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage*; D011654:Pulmonary Edema / Q000139:chemically induced* / Q000209:etiology* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D000077149:Sevoflurane
D008738:Methyl Ethers; D000077149:Sevoflurane; D007530:Isoflurane