Xiao Ying, Wen Jian, Bai Yanxia, Duan Na, Jing G X
Department of Anesthesiology, The First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, P.R.China.
Department of Otolaryngology, The First Affiliated Hospital of Medical College of Xi'an Jiaotong University, Xi'an, P.R.China.
PLoS One. 2014 May 12;9(5):e96861. doi: 10.1371/journal.pone.0096861. eCollection 2014.
To investigate the effects of isoflurane and propofol on mean arterial pressure (MAP), cochlear blood flow (CoBF), distortion-product otoacoustic emission (DPOAE), and the ultrastructure of outer hair cells (OHCs) in guinea pig cochleae.
Forty-eight male guinea pigs were randomly assigned to one of six treatment groups. Groups 1 to 3 were infused (i.v.) with a loading dose of propofol (5 mg/kg) for 5 min and three maintenance doses (10, 20, or 40 mg kg-1·h-1, respectively) for 115 min. Groups 4 to 6 were inhaled with isoflurane at concentrations of 1.15 vol%, 2.30 vol% or 3.45 vol% respectively for 120 min. CoBF and MAP were recorded prior to and at 5 min intervals during drug administration. DPOAE was measured before, immediately after, and 1 h after administration. Following the final DPOAE test, cochleae were examined using scanning electron microscopy.
Propofol treatment reduced MAP in a dose-dependent manner. CoBF and DPOAE showed increases at propofol maintenance doses of 10 and 20 mg kg-1·h-1. Inhalation of isoflurane at concentrations of 2.30 vol% and 3.45 vol% reduced MAP and CoBF. DPOAE amplitude increased following inhalation of 1.15 vol% isoflurane, but decreased following inhalations of 2.30 vol% and 3.45 vol%. Cochlear structure was changed following inhalation of either 2.30 vol% or 3.45 vol% isoflurane.
Propofol could decrease MAP and increase both CoBF and DPOAE without affecting OHC structure. Inhalation of isoflurane at concentrations >2.30 vol% decreased CoBF and DPOAE, and produced injury to OHCs.
研究异氟烷和丙泊酚对豚鼠耳蜗平均动脉压（MAP）、耳蜗血流量（CoBF）、畸变产物耳声发射（DPOAE）以及外毛细胞（OHC）超微结构的影响。
48只雄性豚鼠被随机分为六个治疗组之一。第1至3组静脉输注丙泊酚负荷剂量（5mg/kg）5分钟，然后分别以三个维持剂量（10、20或40mg kg-1·h-1）输注115分钟。第4至6组分别吸入浓度为1.15%、2.30%或3.45%的异氟烷120分钟。在给药前及给药期间每隔5分钟记录CoBF和MAP。在给药前、给药后立即及给药后1小时测量DPOAE。在最后一次DPOAE测试后，使用扫描电子显微镜检查耳蜗。
丙泊酚治疗以剂量依赖性方式降低MAP。在丙泊酚维持剂量为10和20mg kg-1·h-1时，CoBF和DPOAE增加。吸入浓度为2.30%和3.45%的异氟烷会降低MAP和CoBF。吸入1.15%异氟烷后DPOAE幅度增加，但吸入2.30%和3.45%异氟烷后DPOAE幅度降低。吸入2.30%或3.45%异氟烷后耳蜗结构发生改变。
丙泊酚可降低MAP并增加CoBF和DPOAE，而不影响OHC结构。吸入浓度>2.30%的异氟烷会降低CoBF和DPOAE，并对OHC造成损伤。
