1.Effect of hyperbaric oxygen preconditioning on activation of plasma protein C in a rat model of asphyxial cardiac arrest-resuscitation
Zhongyan YAO ; Xiaoyun ZHOU ; Chao WANG
Chinese Journal of Anesthesiology 2015;(12):1495-1497
Objective To investigate the effect of hyperbaric oxygen ( HBO) preconditioning on activation of plasma protein C in a rat model of asphyxial cardiac arrest?resuscitation. Methods A total of 105 adult male Sprague?Dawley rats, aged 70-90 days, weighing 260-320 g, were randomly divided into 3 groups: cardiac arrest group ( group CA, n=5) , cardiac arrest?resuscitation group ( group CA∕R, n=50) , and hyperbaric oxygen preconditioning group ( group H, n=50 ) . Cardiac arrest was induced by campling the endotracheal tube at the end of expiration. The animals underwent HBO preconditioning once a day for 3 consecutive days before cardiac arrest was induced in group H. The rats were placed in the HBO chamber, 10 min later the pressure was increased at a constant rate until the hyperbaric oxygen reached 2 atmosphere absolute, and maintained at this level for 45 min, after the oxygen concentration>95%, and then the pressure was decreased at a constant rate ( within 20 min) until the normal pressure was reached. The rats underwent no resuscitation in group CA. Five rats were selected from CA∕R and H groups at 3, 6, 12 and 24 h after restoration of spontaneous circulation, and at 30 min of cardiac arrest in group CA, and blood samples were taken from the abdominal aorta for determination of the plasma activated protein C ( APC) concentrations. The time from asphyxia to cardiac arrest, time for spontaneous regular cardiac rhythm, and successful resuscitation were recorded. Results Compared with group CA, the plasma APC concentrations were significantly decreased at each time point after restoration of spontaneous circulation in CA∕R and H groups ( P<0.05) . Compared with group CA∕R, the time from asphyxia to cardiac arrest was significantly prolonged, the time for spontaneous regular cardiac rhythm was shortened, the success rate of resuscitation was increased, and the plasma APC concentrations were increased at each time point after restoration of spontaneous circulation in group H ( P<0. 05 ) . Conclusion HBO preconditioning can promote activation of plasma protein C after resuscitation in a rat model of asphyxial cardiac arrest, and is helpful in improving hypercoagulation.
2.Dynamic changes of thyroid function during gestation: A self-sequential longitudinal study
Xiaomei ZHANG ; Baoting YAO ; Danyang WANG ; Chenyan LI ; Zhongyan SHAN ; Weiping TENG
Chinese Journal of Endocrinology and Metabolism 2014;30(12):1053-1057
Objective To evaluate the trimester specific reference ranges and dynamic changes of thyroid functional indicators during gestation of healthy pregnant women.Methods According to the selection criteria,139 cases were selected as the normal pregnant population to establish a self-sequential longitudinal reference range.We collected samples eight times in every case throughout the gestation(including the 8th,12th,16th,20th,28th,36th week of prenatal,the 3rd and the 6th month postpartum) and detected the indicators of thyroid funciton.Meanwhile,301 healthy non-pregnant women of childbearing age were selected as the control group.Results The median of TSH was lowest in the first trimester,and then was increased in the second and third trimesters.The reference ranges of TSH were 0.20-4.01 mIU/L,0.43-3.97 mIU/L,and 0.57-3.96 mIU/L in the above trimesters.The free thyroxine (FT4) level from the 12th week of gestation to the 6th month of postpartum was gradually decreased and was lower than the non-pregnant level.The total thyroxine (TT4) was significantly increased at the 12th week of gestation and thereafter it was stable and returned to normal after childbirth.The free triiodothyronine(FT3) was gradually declined from the 12th week to the 28th week and returned to normal postpartum.Total triiodothyronine(TT3) was significantly increased at the 12th week and thereafter was stable,and returned to normal after childbirth.There was a significant negative correlation between TSH and FT4 in the first trimester(P<0.01).There was no correlation between TSH and TT4 during the whole gestation.There were positive correlations between FT4 and TT4,FT3 and TT3 since the 12th week of gestation (P < 0.01).Conclusions The gestational specific reference range of TSH based on the selfsequential longitudinal study was narrow,however,the upper limit was still higher than that recommended in foreign guidelines.
3.Effects of penehyclidine hydrochloride on synthesis and release of HMGB1 in macrophages induced by lipopolysaccharide in mice
Qiang YANG ; Yulin CHANG ; Xiangge LIU ; Zhongyan YAO ; Qianjie WEI ; Zhaohui LIU
Chinese Journal of Anesthesiology 2014;34(2):245-248
Objective To evaluate the effects of penehyclidine hydrochloride on synthesis and release of high mobility group protein box 1 (HMGB1) in macrophages induced by lipopolysaccharide (LPS) in mice.Methods RAW264.7 cells obtained from mice were seeded in the culture dishes.After being cultured for 24 h,the cells were randomly divided into 5 groups (n =6 each) using a random number table.The cells were incubated routinely in group C.The cells were incubated in the presence of LPS 500 ng/ml (group LPS),LPS 500 ng/ml + penehyclidine hydrochloride 0.5 μg/ml (group P1),LPS 500 ng/ml + penehyclidine hydrochloride 2 μg/ml (group P2),or LPS 500 ng/ml + penehyclidine hydrochloride 5 μg/ml (group P3).All the cells were incubated for 24 h.The cells and supernatant were collected.The proliferation of the cells was measured by CCK-8 assay,HMGB1 mRNA expression in the cells was detected by RT-PCR,NF-κBp65 protein expression in the cells was detected by Western blot and the concentration of HMGB1 in the supernatant was detected by ELISA.Results Compared with group C,the expression of HMGB1 mRNA and NF-κBp65 protein in the cells was significantly upregulated,and the concentration of HMGB1 in the supernatant was increased in LPS,P1,P2 and P3 groups (P < 0.05).Compared with group LPS,the expression of HMGB1 mRNA and NF-κBp65 protein in the cells was significantly down-regulated,and the concentration of HMGB1 in the supernatant was decreased in P2 and P3 groups (P < 0.05).Compared with group P1,the expression of HMGB1 mRNA and NF-κBp65 protein in the cells was significantly down-regulated,and the concentration of HMGB1 in the supernatant was decreased in P2 and P3 groups (P < 0.05).There was no significant difference in the indicators mentioned above between group P2 and group P3 (P > 0.05).There was no significant difference in the proliferation of the cells among the 5 groups (P > 0.05).Conclusion Penehyclidine hydrochloride can reduce the synthesis and release of HMGB1 in macrophages induced by LPS through inhibiting NF-κB activation in mice.
4.Efficacy of acupuncture combined with tropisetron in treating nausea and vomiting induced by car-boprost tromethamine in cesarean section
Zhongyan YAO ; Yulin CHANG ; Lili YU ; Panpan SONG ; Qianjie WEI ; Zhiquan SHEN ; Qiang YANG
Chinese Journal of Anesthesiology 2017;37(10):1184-1187
Objective To evaluate the efficacy of acupuncture combined with tropisetron in treating nausea and vomiting induced by carboprost tromethamine in cesarean section. Methods Sixty-six patients aged 22-40 yr who received carboprost tromethamine and developed nausea and vomiting during cesarean section under lumbar anesthesia, were randomly divided into 3 groups(n=22 each): acupuncture group (group A), tropisetron group(group T)and acupuncture+ tropisetron group(group AT). In group A, 09% normal saline 2 ml was intravenously injected immediately, acupuncture was given at Renzhong, Neiguan and Hegu acupoints with lifting thrusting twirling the acupuncture needle for 10 min. In group T, tropisetron 10 mg was intravenously injected immediately, the needle was placed on Renzhong, Neiguan and Hegu skin surface. In group AT, tropisetron 10 mg was intravenously injected immediately, acupunc-ture was given at Renzhong, Neiguan and Hegu acupoints with lifting thrusting twirling the acupuncture nee-dle for 10 min. The nausea and vomiting score was assessed before anesthesia induction(T0), when nause-a or vomiting occurred(T1)and at 1, 3, 5 and 15 min after acupuncture or administration(T1-5). The degree of patient′s satisfaction with therapeutic effect was recorded. Results Compared with group A, the nausea and vomiting scores were significantly decreased at T4, and the patient's satisfaction score was in-creased in group AT(P<005). Compared with group T, the nausea and vomiting scores were significantly decreased at T2-4and the patient's satisfaction score was increased in group AT(P <005). Conclusion Acupuncture combined with ondansetron can quickly and effectively relieve the nausea and vomiting induced by carboprost tromethamine during cesarean section.
5.Relationship between mechanism underlying methylprednisolone-induced alleviation of ventilator-induced lung injury and p38MAPK/NLRP3 pathway in lung tissues of rats
Zhongyan YAO ; Min QU ; Wenbo SUN ; Ning LOU ; Peng CHEN ; Xiuwei SUN ; Dongdong HUANG
Chinese Journal of Anesthesiology 2021;41(12):1528-1531
Objective:To evaluate the relationship between the mechanism underlying methylprednisolone-induced alleviation of ventilator-induced lung injury (VILI) and p38 mitogen-activated protein kinase (p38 MAPK)/nucleotide binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3) pathway in lung tissues of rats.Methods:Sixty clean-grade male Sprague-Dawley rats, weighing 270-320 g, aged 4-5 months, were divided into 3 groups ( n=20 each) using a random number table method: control group (group C), mechanical ventilation group (group V), and methylprednisolone group (group M). Group C breathed air spontaneously for 4 h without mechanical ventilation.Group V was mechanically ventilated (RR 40 times/min, V T 40 ml/kg, I∶E 1∶1, PEEP 0, FiO 2 21%) for 4 h. Group M received intravenous methylprednisolone 10 mg/kg at 20 min before mechanical ventilation.At 4 h of mechanical ventilation, broncho-alveolar lavage fluid (BALF) was collected to measure the concentrations of interleukin-1beta (IL-1β), IL-18, and tumor necrosis factor-alpha (TNF-α) and wet/dry lung weight ratio (W/D ratio), and lung tissues were obtained for microscopic examination of the histopathological changes and for detection of the expression of p38MAPK, phosphorylated p38MAPK (p-p38MAPK), NLRP3, apoptosis-related speck-like protein containing a CARD (ASC), and cysteinyl aspartate-specific protease-1 (caspase-1) (using Western blot). Results:Compared with group C, the W/D ratio of lung tissues and concentrations IL-1β, IL-18 and TNF-α in BALF were significantly increased, and the expression of p-p38MAPK, NLRP3, ASC and caspase-1 was up-regulated in group V ( P<0.05), and no significant change was found in group M ( P>0.05). Compared with group V, the W/D ratio of lung tissues and concentrations of IL-1β, IL-18 and TNF-α in BALF were significantly decreased, and the expression of p-p38MAPK, NLRP3, ASC and caspase-1 was down-regulated in group M ( P<0.05). Conclusion:The mechanism by which methylprednisolone alleviates VILI may be related to inhibition of p38MAPK/NLRP3 pathway activity and reduction of inflammatory responses in lung tissues of rats.
6.Role of Akt/GSK3β signal pathway in baicalin improving the cognitive function of mice with brain injury induced by mechanical ventilation
Min QU ; Wenbo SUN ; Zhongyan YAO ; Xiuqing ZHANG ; Huiwu ZHANG ; Lei CHEN ; Zilong QI
Chinese Journal of Behavioral Medicine and Brain Science 2022;31(12):1073-1079
Objective:To investigate the effect of baicalin on cognitive function of mice with brain injury induced by mechanical ventilation and its mechanism.Methods:Seventy two C57BL6 mice, weighing 20-25 g, aged 8-12 weeks, were randomly divided into control group (group C), mechanical ventilation group (group V), baicalin group (group B), baicalin+ Akt inhibitor MK-2206 group (group BM) according to random number table method, with 18 in each group.Mice in group C did not have mechanical ventilation and breathed air independently for 6 hours.Mice in group V received mechanical ventilation for 6 hours.Mice in group B and group BM were intraperitoneally injected with baicalin 100 mg/kg 30 minutes before mechanical ventilation, and mice in group BM were injected intraventricular with Akt inhibitor MK-2206 300 μg/kg 60 minutes before mechanical ventilation.Six mice in each group were randomly selected to test their learning and memory abilities by Morris water maze test 1st day before mechanical ventilation and 3rd day and 7th day after mechanical ventilation.One day after mechanical ventilation, six mice in each group were killed, and the brain tissue was taken.TUNEL method was used to detect the neuronal apoptosis in hippocampal CA1 area, and the apoptosis index was calculated.One day after mechanical ventilation, six mice in each group were killed, and the hippocampus was taken, Western blot was used to detect the protein expressions of caspase-3, caspase-9, Akt, p-Akt, GSK-3β and p-GSK-3β.SPSS 22.0 software was used for statistical analysis of data, repeated measure ANOVA and one-way ANOVA were used for comparison between multiple groups.LSD- t test was used for further pairwise comparison. Results:The results of water maze test showed that the time and group interaction of the four groups were not significant ( F=1.14, P>0.05), the main effect of time and group were both significant ( F=47.36, 59.65, both P<0.05). At 3rd day and 7th day after mechanical ventilation, the escape latencies of mice in group V were higher than those in group C (both P<0.05), and the numbers of platform crossing were lower than those in group C (both P<0.05). And 3 days and 7 days after mechanical ventilation, the escape latencies of mice in group B were lower than those in group V (both P<0.05) and the numbers of platform crossing were higher than those in group V (both P<0.05). The escape latenies of mice in BM group on the 3rd and 7th day were higher than those in group B (both P<0.05), and the numbers of platform crossing were lower than those in group B on the 3rd day and 7th day after mechanical ventilation(both P<0.05). TUNEL and Western blot results showed that apoptosis index of hippocampal neurons and expression levels of apoptosis-related proteins caspase-3 and caspase-9 were significant different in the four groups ( F=51.42, 41.21, 40.19, all P<0.05). The apoptosis index of hippocampal neurons ((40.6±3.9)%), the expression levels of caspase-3 (4.93±0.92) and caspase-9 (4.81±0.88) in the hippocampus of mice in group V were higher than those in group C ((13.7±1.4)%, (1.87±0.27), (1.71±0.25), all P<0.05), the apoptosis index of hippocampal neurons ((15.6±1.6)%), the expression levels of caspase-3 (1.95±0.30) and caspase-9 (1.76±0.28) in group B were lower than those in group V ((40.6±3.9)%, (4.93±0.92), (4.81±0.88), all P<0.05), the apoptosis index of hippocampal neurons ((27.8±2.7)%), the expression levels of caspase-3 (3.58±0.61) and caspase-9 (3.49±0.57) in BM group were higher than those in group B ((15.6±1.6)%, (1.95±0.30), (1.76±0.28), all P<0.05). Expression level of p-Akt, p-GSK-3β in hippocampal tissues of the four group of mice were significantly different ( F=37.54, 43.23, both P<0.05). The expression level of p-Akt (0.51±0.06) and p-GSK-3β (0.47±0.05) of hippocampal tissues of mice in group V were lower than those of group C ((1.07±0.10), (1.11±0.12), both P<0.05), the expression level of p-Akt (0.99±0.10) and p-GSK-3β (1.08±0.09) of hippocampal tissues of mice in group B were higher than those of group V (both P<0.05), the expression level of p-Akt (0.83±0.08) and p-GSK-3β (0.81±0.07) of hippocampal tissues of mice in group BM were lower than those in group B (both P<0.05). Conclusion:Baicalin can improve the cognitive function of mice with brain injury induced by mechanical ventilation, which is related with activation of Akt/GSK-3β signaling pathway and inhibition of hippocampal neuron apoptosis.
7.Effects of dexmedetomidine on alveolar epithelial barrier function in rats with VILI and the role of PKC
Min QU ; Wenbo SUN ; Zhongyan YAO ; Cuili JIAO ; Xiuqing ZHANG ; Shuhua LI ; Dongdong HUANG
Chinese Journal of Anesthesiology 2022;42(6):695-699
Objective:To evaluate the effects of dexmedetomidine on alveolar epithelial barrier function in rats with ventilator-induced lung injury (VILI), and the role of protein kinase C (PKC).Methods:One hundred clean-grade male Sprague-Dawley rats, weighing 270-320 g, aged 4-5 months, were divided into 5 groups ( n=20 each) using a random number table method: control group (group C), VILI group (group V), PKC inhibitor group (group B), dexmedetomidine group (group D), and dexmedetomidine plus PKC agonist group (DP group). The VILI model was developed by mechanical ventilation with a tidal volume of 40 ml/kg for 4 h in anesthetized animals.Group C breathed air autonomously for 4 h without mechanical ventilation.Group V was mechanically ventilated for 4 h. In group B, bisindolvlmaleimide I 0.12 mg/kg was injected intramuscularly 1 h before mechanical ventilation.In D and DP groups, dxmedetomidine 5.0 μg/kg was injected intravenously at 20 min before mechanical ventilation, and dexmedetomidine was intravenously infused at the rate of 5.0 μg·kg -1·h -1 during mechanical ventilation.In group DP, PKC agonist phorbol-12-myristic acid-13-acetate 15 μg/kg was intraperitoneally injected at 30 min before mechanical ventilation.At 4 h of mechanical ventilation, oxygenation index (OI), lung permeability index (LPI) and wet/dry lung weight (W/D) ratio were measured, the pathological changes of lung tissues were observed, and lung injury was assessed and scored.The expression of PKC, occludin and ZO-1 protein was detected by Western blot, and the expression of PKC mRNA, occludin mRNA and ZO-1 mRNA was determined by real-time polymerase chain reaction. Results:Compared with group C, OI was significantly decreased, LPI, W/D ratio and lung injury score were increased, the expression of PKC protein and mRNA was up-regulated, and the expression of occludin and ZO-1 protein and mRNA was down-regulated in V and DP groups ( P<0.05), and no significant change was found in the parameters mentioned above in B and D groups ( P>0.05). Compared with group V, OI was significantly increased, LPI, W/D ratio and lung injury score were decreased, the expression of PKC protein and mRNA was down-regulated, and the expression of occludin and ZO-1 protein and mRNA was up-regulated in B, D and DP groups ( P<0.05). Compared with group D, OI was significantly decreased, LPI, W/D ratio and lung injury score were increased, the expression of PKC protein and mRNA was up-regulated, and the expression of occludin and ZO-1 protein and mRNA was down-regulated in group DP ( P<0.05). Conclusions:Dexmedetomidine can reduce the damage to alveolar epithelial barrier function in rats with VILI, and the mechanism is related to inhibition of PKC activation and up-regulation of the expression of occludin and ZO-1.
8.Comparison of internal jugular vein diameter and brachial artery peak velocity variation in predicting fluid responsiveness
Zhongyan YAO ; Wenbin LIU ; Min QU ; Zhaohui LIU ; Jing LI ; Qiang YANG
Chinese Journal of Anesthesiology 2018;38(2):215-218
Objective To compare internal jugular vein diameter and brachial artery peak velocity variation (VVp) in predicting fluid responsiveness.Methods Sixty American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients,of New York Heart Association I,aged 18-64 yr,scheduled for elective gastrointestinal surgery under general anesthesia,were included in this study.Six percent hydroxyethyl starch 130/0.47 ml/kg was infused at a rate of 0.4 ml · kg-1 · min-1 after induction of anesthesia.The patients with the changing rate of stroke volume variation (ASVV) more than or equal to 15% were included in responsiveness group and patients with ASVV less than 15% were included in non-responsiveness group after volume expansion.Immediately after volume expansion and at 3 min after volume expansion,mean arterial pressure,central venous pressure and heart rate were recorded,the maximum diameter of the internal jugular vein at the end of inspiration (IJVmax) and the minimum diameter of the internal jugular vein at end of expiration (IJVmin) and brachial artery peak velocity were measured using an ultrasonic instrument,and the variation of internal jugular vein respiration (VIJV) and VVp were calculated.The receiver operating characteristic curve was used to evaluate the accuracy of IJV IJVmin,VIJV and VVp in predicting fluid responsiveness.Results There were 31 patients in responsiveness group and 29 patients in non-responsiveness group.Compared with non-responsiveness group,mean arterial pressure,central venous pressure,IJVmax and IJVmin were significantly decreased and heart rate,VIJV and VVp were increased immediately after volume expansion in responsiveness group (P<0.05).The areas under receiver operating characteristic curve (AUC) of IJV IJVmin,VIJV and VVp were 0.753,0.948,0.837 and 0.832,respectively.AUC IJVmax,AUCVIJV and AUCVVp were significantly decreased when compared with AUC IJVmin (P<0.05).Conclusion The accuracy of IJVmax is higher than that of VVp in predicting intraoperative fluid responsiveness in the patients.
9.Accuracy of lung recruitment maneuver combined with brachial artery peak velocity variation in predicting fluid responsiveness
Min QU ; Zhongyan YAO ; Tianlin LIU ; Jing LI ; Juan WANG ; Ning YAN ; Qiang YANG ; Mingyuan LIU
Chinese Journal of Anesthesiology 2020;40(2):217-220
Objective:To evaluate the accuracy of lung recruitment maneuver (LRM) combined with brachial artery peak velocity variation (ΔVp) in predicting fluid responsiveness.Methods:Sixty-four patients of both sexes, aged 18-64 yr, with body mass index 19-26 kg/m 2, of American Society of Anesthesiologists physical status Ⅰor Ⅱ, with New York Heart Association class Ⅰor Ⅱ, scheduled for elective open gastrointestinal surgery under general anesthesia, were enrolled in this study.LRM (positive airway pressure was maintained at 30 cmH 2O for 10 s) and volume loading test were performed in sequence after anesthesia induction.ΔVp was measured by ultrasonography at the beginning of LRM.Mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP) and stroke volume (SV) were recorded before LRM (T 1), during LRM (T 2), before volume expansion (T 3) and after volume expansion (T 4). The changing rate of each index before and after LRM (ΔMAP LRM, ΔHR LRM, ΔCVP LRM, ΔSV LRM) and before and after volume expansion (ΔMAP VE, ΔHR VE, ΔCVP VE, ΔSV VE) were calculated.ΔSV VE≥15% was considered to be a positive response after volume expansion, and patients were divided into response group (≥ 15%, R group) and non-response group (< 15%, NR group). Results:There were 34 cases in R group and 30 cases in NR group.Compared with NR group, MAP at T 2 and SV at T 1, 2 were significantly decreased, ΔMAP LRM, ΔMAP VE, ΔSV LRM and ΔSV VE were increased, and ΔVp was increased in group R ( P<0.05). There was a positive correlation between ΔVp and ΔSV VE ( r=0.829, P<0.05), a negative correlation between ΔSV LRM and ΔSV VE ( r=-0.876, P<0.05), and a negative correlation between ΔVp and ΔSV LRM ( r=-0.819, P<0.05). The area under the receiver operating characteristic curve of LRM combined with ΔVp was 0.808, and the cut-off value was 32.3%, the sensitivity 75.3%, and the specificity 88.2%. Conclusion:LRM combined with ΔVp (≥32.3%) can accurately predict the intraoperative fluid responsiveness in patients.
10.Efficacy of ultrasound-guided superior laryngeal nerve block combined with intravenous anesthesia for improving pediatric fiberoptic bronchoscopy
Zhongyan YAO ; Ning LOU ; Manman QI ; Yu WANG ; Wang LIU ; Xiuwei SUN ; Guoliang TANG
Chinese Journal of Anesthesiology 2023;43(10):1197-1200
Objective:To evaluate the efficacy of ultrasound-guided superior laryngeal nerve block(SLNB) combined with intravenous anesthesia for improving pediatric fiberoptic bronchoscopy.Methods:Forty pediatric patients of either sex, aged 3-6 yr, of American Society of Anesthesiologists Physical Status classificationⅠor Ⅱ, with body mass index of 18-24 kg/m 2, undergoing fiberoptic bronchoscopy in Cangzhou Central Hospital in 2022, were divided into 2 groups ( n=20 each) by a random number table method: ultrasound-guided SLNB plus intravenous anesthesia group (group A) and topical anesthesia plus intravenous anesthesia group (group B). After sedation with dexmedetomidine and esketamine, ultrasound-guided bilateral SLNB was performed with 1% lidocaine 0.5 ml (for each side)in group A, and topical anesthesia was performed with 1% lidocaine in nasal and pharyngeal cavities in group B. After completion of the surgery procedure, propofol was continuously infused at 5 mg·kg -1·h -1 until completion of diagnosis and treatment. An increment of propofol 1 mg/kg was intravenously given if severe bucking or body movement occurred during operation. Mean arterial pressure (MAP), heart rate (HR) and SpO 2 were recorded on admission to the operating room (T 0), immediately after sedation (T 1), immediately after bronchoscopy entering the glottis (T 2), 5 min after start of treatment (T 3) and at the end of examination (T 4). The occurrence of intraoperative hypoxemia, HR <60 bpm, and MAP <50 mmHg were recorded, and the additional dose of propofol was recorded. The venous blood samples were collected at T 0 and T 4 to determine plasma cortisol concentrations by chemiluminescence.The surgeon′s satisfaction score was recorded. The complications of SLNB were also recorded within 2 h after operation in group A. Results:Compared with group B, HR was significantly decreased at T 2 and T 3, SpO 2 was increased, the intraoperative additional dosage of propofol and incidence of hypoxemia were decreased, and the surgeon′s satisfaction score was increased, and the concentrations of cortisol were decreased at T 4 in group A ( P<0.05). No HR<60 bpm and MAP<50 mmHg were found in two groups. No SLNB-related complications were observed after operation in group A. Conclusions:Ultrasound-guided SLNB combined with intravenous anesthesia is safer for pediatric fiberoptic bronchoscopy and can improve the analgesic effect and is more helpful in inhibiting intraoperative stress responses when compared with conventional anesthesia.