Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding

BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion.

A Comparison of Arterial Oxygenation between 60% O2 CPAP and 100% O2 CPAP during One-Lung Ventilation: A Prospective Randomized Controlled Study

Background: One-lung ventilation (OLV) is generally adopted for thoracic surgery. The systemic application of a high fraction of inspiratory oxygen (F1O2) and continuous positive airway pressure (CPAP) to the non-ventilated lung is useful for preventing arterial oxygen desaturation. The adverse effects of elevated F1O2 include oxidative lung injury, resorption atelectasis and coronary and peripheral vasoconstriction. It is preferable to avoid hyperoxemia in patients with complications such as chronic obstructive pulmonary disease, idiopathic pneumonia, and bleomycin-treated lungs. We aimed to determine whether the application of 60% O2 CPAP to the non-ventilated lung is sufficient to provide adequate oxygenation with 60% O2 to the ventilated lung. Methods: A total of 70 patients scheduled to receive elective thoracic surgery requiring OLV were recruited. Left double-lumen tubes were applicable in all surgeries. Patients were randomly allocated to one of two groups, to receive either 60% O2 CPAP (60% CPAP group, n = 35), or 100% O2 CPAP (100% CPAP group, n = 35) at a setting of 2 - 3 cmH2O, applied to the non-ventilated lung. Arterial blood gas analyses were obtained at the following stages: RA, spontaneous breathing under room air (RA);TLV, during total lung ventilation (TLV) prior to the initiation of OLV;T5, 5 min after the initiation of OLV;T15, 15 min after the initiation of OLV;T30, 30 min after the initiation of OLV. Results: The PaO2 value in 60% CPAP group vs. 100% CPAP group at each measurement were as follows: RA (mean [standard deviation: SD], 89.7 [8.2] mmHg vs. 85.8 [11.9] mmHg);TLV (277.9 [52.9] mmHg vs. 269.2 [44.0] mmHg);T5 (191.4 [67.9] mmHg vs. 192.3 [66.0] mmHg);T15 (143.2 [67.3] mmHg vs. 154.7 [60.8] mmHg) and T30 (95.6 [32.0] mmHg vs. 112.5 [36.5] mmHg), respectively. Among the five measurement points, T30 was the only time point at which the 100% CPAP group showed a significantly greater PaO2 value than the 60% CPAP group (p = 0.0495). The SaO2 at T30 in the 100% CPAP group (97.4 [2.0]%) was also significantly greater than that in the 60% CPAP group (96.3 [2.2]%, p = 0.039). No differences were found between the groups regarding changes to the overall PaO2 values (p = 0.44) and SaO2 values (p = 0.23) during the study period. Conclusions: Oxygenation could be safely maintained in relatively healthy patients with 60% O2 OLV and 60% O2 CPAP. The application of 60% O2 CPAP during OLV for patients who are not suited to exposure to high F1O2 may be an alternative form of respiratory management.

Clinical Study of P_(ET)CO_2 in One-lung Ventilation

Fourty-eight patients (ASA physical status Ⅰ - Ⅱ) undergoing selected thoracotomy and pulmonectomy were studied. They were divided into two groups according to different respiratory modes, two-lung ventilation (TLV) and onelung ventilation (OLV) or TLV and OLV with a Bain cyclic system for CPAP on the side of operated lung. PETCO2 and PaCO2 were measured after 30 min TLV,30 min and 60 min OLV, and repeated TLV (R-TLV) 30 min after pulmonectomy, to evaluate the difference between PETCO2 and PaCO2 in OLV and to observethe effect of abating hypoxemia and discharge of CO2 in OLV with Bain system.Our results showed that the PaCO2 and PETCO2 in different test groups were normal though the measured values in OLV were slightly higher than that in TLV (P<0. 05) , and then they were recovered after R-TLV (P>0. 05). There was nosignificant difference between group 1. and 2. in OLV (P>0. 05). There was aclose correlation between PETCO2 and PaCO2 (P<0. 05). The differences of the calculated P(a-ET)CO2 and radio of PETCO2/PaCO2 in different ventilation modes were not significant. Hypoxemia in OLV was corrected by Bain system, but the discharge of CO2 was not affected. The results showed that measurement of PET CO2 as a non-invasive procedure can be commonly used to monitor OLV.

Effect of sevoflurane pretreatment combined with propofol on cerebral oxygen metabolism and inflammatory response during one-lung ventilation

Objective:To study the effect of sevoflurane pretreatment combined with propofol on cerebral oxygen metabolism and inflammatory response during one-lung ventilation.Methods:A total of 92 patients who accepted pulmonary lobectomy under one-lung ventilation in Changzheng Hospital Affiliated to Second Military Medical University between August 2014 and March 2016 were selected and divided into sevoflurane group and control group. Before one-lung ventilation (T1), 30 min after one-lung ventilation (T2) and 60 min after one-lung ventilation (T3), cerebral oxygen metabolism indexes and serum inflammation indexes were determined;after surgical resection, the lung tissue was collected to determine the expression of inflammatory signaling molecules and hypoxia injury molecules.Results: CjvO2 and ajdDCO2 levels as well as serum ICAM-1, IL-1β and TNF-α contents were not significantly different between two groups of patients at T1;CjvO2 levels as well as serum ICAM-1, IL-1β and TNF-α contents of sevoflurane group at T2 and T3 were significantly lower than those of control group while ajdDCO2 levels were significantly higher than those of control group;after surgical resection, TLR4, NF-kB, AQP-4, p38MAPK, HO-1, GLUT-1, HIF-1毩 and CHOP protein expression in lung tissue of sevoflurane group were significantly lower than those of control group.Conclusion:Sevoflurane pretreatment combined with propofol can improve the cerebral oxygen metabolism and inhibit the inflammatory response during one-lung ventilation.

Effect of sevoflurane pretreatment on alveolar oxygenation function and systemic inflammatory response activation during one-lung ventilation

Objective:To study the effect of sevoflurane pretreatment before one-lung ventilation on pulmonary compliance, oxygenation function and systemic inflammatory response.Methods:104 patients who accepted one-lung ventilation operation in Mianyang Central Hospital between April 2014 and December 2015 were selected and randomly divided into the sevoflurane group who accepted sevoflurane pretreatment combined with routine anesthesia and the control group who accepted routine anesthesia, and the pulmonary compliance and oxygenation function parameters during one-lung ventilation as well as the contents of inflammatory mediators in serum and the contents of inflammation regulation molecules in alveolar lavage fluid were determined.Results: At T1, T2 and T3, Cdyn and PaO2/FiO2 levels of sevoflurane group were significantly higher than those of control group, and serum ICAM-1, IL-6, IL-8 and TNF-α contents were significantly lower than those of control group while IL-10 contents were significantly higher than those of control group;after operation, AQP-1, p38MAPK, TLR4 and NF-κB contents in collapsed alveolar lavage fluid of sevoflurane group were significantly lower than those of control group.Conclusion: Sevoflurane pretreatment before one-lung ventilation can improve the pulmonary compliance and oxygenation function, and inhibit the activation of inflammatory response.

Effect of sevoflurane pretreatment on cerebral oxygen saturation, pulmonary compliance and systemic stress response in patients with one-lung ventilation

Objective:To investigate the effect of sevoflurane pretreatment on cerebral oxygen saturation, pulmonary compliance and systemic stress response in patients with one-lung ventilation. Methods:A total of 70 patients with lung cancer who accepted the selective pulmonary lobectomy in our hospital between January 2012 and December 2015 were collected and divided into observation group and control group (n=35) according to the single-blind randomized control method. After general anesthesia induction, the control group received air/oxygen mixed ventilation, and the observation group received sevoflurane pretreatment for 30 min and received one-lung ventilation after that. Immediately after anesthesia induction (T0), 30 min after sevoflurane pretreatment (T1), 60 min after sevoflurane pretreatment (T2) and at chest wall suture after operation (T3), the cerebral oxygen saturation monitor was used to determine the left and right regional cerebral oxygen saturation (rSO2);end-expiratory airway blocking method and related indexes were used to calculate the contralateral pulmonary static compliance (Cst) and pulmonary dynamic compliance (Cdyn);the RIA method was used to determine serum stress hormone levels.Results:At T0, differences in cerebral oxygen saturation, pulmonary compliance and systemic stress response were not statistically significant between two groups of patients;at T1, T2 and T3, left and right rSO2 levels of observation group were higher than those of control group, Cst and Cdyn levels were significantly higher than those of control group, and serum epinephrine (E), norepinephrine (NE), cortisol (Cor) and angiotensinⅡ (AngⅡ) levels were lower than those of control group.Conclusion:Sevoflurane pretreatment can promote the intraoperative cerebral oxygen saturation and pulmonary compliance, and reduce systemic stress response in patients with one-lung ventilation.

Oxygenation,inflammatory response and lung injury during one lung ventilation in rabbits using inspired oxygen fraction of 0.6 vs.1.0

Maintaining adequate oxygenation during one-lung ventilation（OLV） requires high inspired oxygen fraction（FiO_2）.However,high FiO_2 also causes inflammatory response and lung injury.Therefore,it remains a great interest to clinicians and scientists to optimize the care of patients undergoing OLV.The aim of this study was to determine and compare oxygenation,inflammatory response and lung injury during OLV in rabbits using FiO_2 of 0.6 vs.1.0.After 30 minutes of two-lung ventilation（TLV） as baseline,30 rabbits were randomly assigned to three groups receiving mechanical ventilation for 3 hours：the sham group,receiving TLV with 0.6 FiO_2;the 1.0 FiO_2 group,receiving OLV with 1.0 FiO_2;the 0.6 FiO_2 group,receiving OLV with 0.6 FiO_2.Pulse oximetry was continuously monitored and arterial blood gas analysis was intermittently conducted.Histopathologic study of lung tissues was performed and inflammatory cytokines and the mRNA and protein of nuclear factor kappa B（NF-κB） p65 were determined.Three of the 10 rabbits in the 0.6 FiO_2 group suffered hypoxemia,defined by pulse oximetric saturation（SpO_2） less than 90%.Partial pressure of oxygen（PaO_2）,acute lung injury（ALI） score,myeloperoxidase（MPO）,tumor necrosis factor-a（TNF-α）,interleukin-6（IL-6）,mRNA and protein of NF-kB p65 were lower in the 0.6 FiO_2group than in the 1.0 FiO_2 group.In conclusion,during OLV,if FiO_2 of 0.6 can be tolerated,lung injury associated with high FiO_2 can be minimized.Further study is needed to validate this finding in human subjects.

The Effect of Dexmedetomidine on Oxygenation and Intrapulmonary Shunt during One Lung Ventilation

Background: The effect of intravenously administered dexmedetomidine on oxygenation during one-lung ventilation has not been studied. The hypothesis of this prospective, randomized study was that dexmedetomidine would be associated with an improvement in oxygenation during one-lung ventilation. The secondary outcome was the change in the intrapulmonary shunt. Materials and Methods: Thirty patients undergoing one-lung ventilation were included. Patients in Group D (n = 15) received a bolus dose of 1 μg·kg-1 dexmedetomidine at 10 min after induction of anaesthesia followed by an infusion of 0.4 μg·kg-1·hr-1 that was stopped at the end of the surgery, and those in the control group(Group C, n = 15) were given saline at the same dosage. Vital signs, PaO2, and pulmonary shunting (Qs/Qt) were compared. Results: During one-lung ventilation, the PaO2 in Group D increased significantly and Qs/Qt significantly decreased compared to Group C (PaO2, 203.7 ± 42.3 mmHg vs. 173 ± 37.6 mmHg [P = 0.04] and Qs/Qt 19.8% ± 4.5% vs. 31% ± 2.4% [P < 0.0001], Group D and Group C, respectively). Conclusion: Intravenous administration of dexmedetomidine achieved an improvement in oxygenation during one-lung ventilation. This was associated with a decrease in pulmonary shunt. Use of intraoperative dexmedetomidine during thoracic surgery can be suggested.

预先单肺通气联合呼吸暂停对支气管封堵器用于胸腔镜手术单肺通气时肺萎陷的影响

目的 探讨预先单肺通气(OLV)联合呼吸暂停对支气管封堵器(BB)用于胸腔镜手术行OLV时肺萎陷的影响。方法 选择择期行胸腔镜下左肺段或肺叶切除术的患者75例,随机分为预先OLV组(A组)、呼吸暂停组(B组)和预先OLV联合呼吸暂停组(C组),每组25例。记录3组打开胸膜到肺完全萎陷的时间、外科医生满意度、进胸前准备时间、OLV时间、手术时间和OLV开始至胸膜打开后20 min内低氧血症[经皮动脉血氧饱和度(SpO_(2))<90%]的发生情况;记录3组胸膜腔开放即刻(T_0)、胸膜腔开放后1 min (T_1)、5 min (T_2)、10 min (T_3)和20 min (T_4)的肺萎陷评分(LCS)。结果 与A组和B组比较,C组肺完全萎陷时间明显缩短,外科医生满意度明显提高,差异均有统计学意义(P <0.05),A组和B组肺完全萎陷时间和外科医生满意度比较,差异均无统计学意义(P> 0.05);与A组比较,B组T0时点LCS低于A组,而在T_1时点,则明显高于A组,C组T_(1)、T_(2)、T_(3)和T_(4)时点LCS明显高于A组和B组,差异均有统计学意义(P <0.05);C组T2时点SpO_(2)明显低于A组和B组,差异有统计学意义(P <0.05)。结论 对于用BB行OLV的胸腔镜手术患者,预先使用OLV联合呼吸暂停,可以改善非通气侧肺的肺萎陷效果,缩短了肺完全萎陷时间,提高了外科医生满意度,且OLV的早期LCS更高,但仍需监测OLV期间的SpO_(2)。

连续气道正压通气对胸腔镜肺部手术患者呼吸功能的影响

目的探讨连续气道正压(CPAP)通气对胸腔镜肺部手术患者呼吸功能的影响。方法选择2021年6月至2022年12月于广西壮族自治区人民医院择期行胸腔镜肺部手术的60例患者,采用随机数字表法将其分为观察组和对照组,每组30例,经剔除后,最终两组各有29例纳入分析。在单肺通气时,观察组术侧肺持续给予CPAP通气,压力为5 cmH_(2)O,对照组术侧肺无特殊干预措施。于双肺通气20 min(T_(0))、单肺通气30 min(T_(1))、单肺通气1 h(T_(2))时间点进行动脉血气分析,比较两组各时间点氧合指数(OI)水平。比较两组术前及术后24 h中性粒细胞比率、白细胞计数。比较两组术后72 h内肺部并发症发生情况。结果在T_(0)~T_(2)时间点,两组OI均呈下降趋势(P<0.05),且在T_(1)、T_(2)时间点,对照组的OI水平较观察组更低,差异有统计学意义(P<0.05)。在手术后,两组白细胞计数、中性粒细胞比率较术前显著升高(P<0.05),两组间比较差异无统计学意义(P>0.05)。观察组术后肺部并发症发生率低于对照组,差异有统计学意义(13.79%vs 37.93%;χ^(2)=4.406,P=0.036)。结论对胸腔镜肺部手术患者的术侧肺实施CPAP通气能有效提高患者单肺通气时的氧合,降低术后肺部并发症发生率。

胸科手术中单肺通气肺萎陷技术的应用进展

相较于传统的开胸手术,胸腔镜手术(video-assisted thoracoscopic surgery,VATS)在手术视野范围较小、操作空间较窄的情况下进行,为了成功进行VATS手术,需要最大程度地优化肺隔离和肺萎陷的质量,延迟肺萎陷的麻醉技术可能阻碍胸外科手术。为了提高肺萎陷的速度和质量,临床上采取了诸多措施。该文就胸外科手术中单肺通气肺萎陷技术的应用和进展进行综述。

PCV中吸气流速对OLV患者呼吸功能及炎症因子的影响

目的比较压力控制通气(PCV)中不同吸气流速对单肺通气(OLV)患者呼吸功能及炎症因子的影响。方法本研究为2018—2019年对75例单肺通气患者的前瞻性研究。患者在麻醉和单肺通气(OLV)后随机分为吸气流量30 L/min(A组)、50 L/min(B组)或70 L/min(C组)。比较OLV前(T0)、OLV后30 min(T1)、60 min(T2)和120 min(T3)的呼吸力学、呼吸功能、血流动力学和血气分析,中心静脉血检测分析IL-6、IL-8、TNF-α和sICAM-1,观察术后3天肺部并发症和ARDS的发生情况。结果三组一般情况、血流动力学指标差异均无统计学意义(P>0.05);B组、C组PaCO2较A组降低(P<0.05);与T0时比较,T1-T3时三组PaO2、SVO2均降低(P<0.05);三组PH、SO2和HB差异均无统计学意义(P>0.05)。与A组比较,B组、C组ΔVT增大(P<0.05);三组Ppeak差异无统计学意义;与A组比较,B组、C组PEEP均增大(P<0.05);与A组比较,T1-T3时B组、C组VD/VT减少(P>0.05);与T0比较,T1-T3时三组Qs/Qt增加(P<0.05);与A组比较,T1-T3时B组、C组Cdyn增大(P<0.05);与T0相比,T1-T3时三组PaO2/FiO2降低(P<0.05);与T0相比,T1-T3时三组IL-6、IL-8、TNF-α和sICAM-1的浓度增多(P<0.05),但A组、B组低于C组(P<0.05)。三组患者发生术后肺部并发症和ARDS差异均无统计学意义。结论在PCV模式下通过增加吸气流速能增加VT,减少死腔率,促进CO2的交换,并且改善肺动态顺应性,但并不能很好的改善氧合及肺内分流。吸气流速50 mL/L在较小炎症反应的情况下达到上述改善呼吸功能和呼吸力学,可推荐应用于进行OLV患者。

术中碳酸氢钠林格液对单肺通气患者的临床观察

目的探讨术中碳酸氢钠林格液对单肺通气(one-lung ventilation,OLV)患者血气指标、炎性因子及电解质的影响。方法选取2020年7月至2022年12月合肥市第二人民医院胸外科拟择期行胸腔镜手术且术中行OLV的患者40例,随机分为试验组和对照组,每组20例,试验组采用碳酸氢钠林格液,对照组采用乳酸钠林格液。比较两组OLV前后不同时刻血气指标、电解质指标、炎性因子指标和不良反应发生率。结果40例患者中男24例,女16例,年龄18~65岁,平均(48.5±12.1)岁。OLV期间试验组SpO_(2)<90%的次数及时间均低于对照组。与入室时(T0)相比,气管插管后双肺通气时(T1)、OLV 30 min(T2)、手术结束前双肺通气时(T3)两组PaO_(2)和SaO_(2)均升高,且T2试验组SaO_(2)高于对照组;T1、T2和T3两组pH和BE均下降,其中T2和T3试验组pH和BE均高于对照组,差异均有统计学意义(P<0.05)。与T0相比,T1、T2和T3两组K^(+)均下降、Cl^(-)均升高;T1、T2和T3试验组Mg^(2+)低于对照组,差异均有统计学意义(P<0.05)。术毕和术后6 h试验组TNF-a、IL-6低于对照组,差异均有统计学意义(P<0.05)。结论碳酸氢钠林格液可改善OLV患者术中呼吸系统的稳定性,维持电解质平衡,减少炎症应激反应。

Can Dexmedetomidine Improve Arterial Oxygenation and Intrapulmonary Shunt during One-lung Ventilation in Adults Undergoing Thoracic Surgery？ A Meta-analysis of Randomized, Placebo-controlled Trials

Background：One-lung ventilation （OLV） is a common ventilation technology during thoracic surgery that can cause serious clinical problems.We aimed to conduct a meta-analysis to compare oxygenation and intrapulmonary shunt during OLV in adults undergoing thoracic surgery with dexmedetomidine （Dex） versus placebo to assess the influence and safety of using Dex.Methods：Randomized controlled trials comparing lung protection in patients who underwent thoracic surgery with Dex or a placebo were retrieved from PubMed,EMBASE,MEDLINE,Cochrane Library,and China CNKI database.The following information was extracted from the paper：arterial oxygen partial pressure （PaO2）,PaO2/inspired oxygen concentration （PaO2/FiO2,oxygenation index [OI]）,intrapulmonary shunt （calculated as Qs/Qt）,mean arterial pressure （MAP）,heart rate （HR）,tumor necrosis factor-α （TNF-α）,interleukin （IL）-6,superoxide dismutase （SOD）,and malondialdehyde （MDA）.Results：Fourteen randomized controlled trials were included containing a total of 625 patients.Compared with placebo group,Dex significantly increased PaO2/FiO2 （standard mean difference [SMD] =0.98,95% confidence interval [CI] [0.72,1.23],P 〈 0.00001）.Besides,Qs/Qt （SMD=-1.22,95% CI [-2.20,-0.23],P =0.020）,HR （SMD=-0.69,95% CI [-1.20,0.17],P =0.009）,MAP （SMD=-0.44,95% CI [-0.84,0.04],P =0.030）,the concentrations ofTNF-α （SMD =-1.55,95% CI [-2.16,-0.95],P 〈0.001）,and IL-6 （SMD =-1.53,95% CI [-2.37,-0.70],P =0.0003） were decreased in the treated group,when compared to placebo group.No significant difference was found in MDA （SMD =-1.14,95% CI [-3.48,1.20],P =0.340） and SOD （SMD =0.41,95% CI [-0.29,1.10],P =0.250） between the Dex group and the placebo group.Funnel plots did not detect any significant publication bias.Conclusions：Dex may improve OI and reduce intrapulmonary shunt during OLV in adults undergoing thoracic surgery.However,this conclusion might be weakened by the limited number of pooled studies and patients.

Investigation of one-lung ventilation postoperative cognitive dysfunction and regional cerebral oxygen saturation relations

Objective： To explore the relationship of postoperative cognitive dysfunction （POCD） in one-lung ventilation （OLV） patients and regional cerebral oxygen saturation （rSO2）. Methods： Twenty-nine male and twenty-one female cases of OLV received thoracic surgery, with American Standards Association （ASA） physical status being at Grades Ⅰ-Ⅲ. Neuropsychological tests were performed on the day before operation and 7 d after operation, and there was an intraoperative continuous monitoring of rSO2. The values of rSO2 before anesthesia induction （t1）, at the beginning of OLV （t2）, and at the time of OLV 30 min （t3）, OLV 60 min （t4）, the end of OLV （t5）, and the end of surgery （t6） were recorded. The intraoperative average of rSO2 （ rSO2 ）, the intraoperative minimum value of rSO2 （rSO2, rn=n）, and the reduced maximum percentage of rSO2 （rSO2, %max） when compared with the baseline value were calculated. The volume of blood loss, urine output, and the amount of fluid infusion was recorded. Results： A total of 14 patients （28%） in the 50 cases suffered from POCD. The values of mini-mental state examination （MMSE）, the digit span and the digit symbol on the 7th day after the operation for POCD in OLV patients were found to be significantly lower than those before the operation （P〈0.05）. The values of MMSE and vocabulary fluency scores were significantly lower than those in the non-POCD group （P〈0.05）. The values of rSO2 in the POCD group of OLV patients at t2 and t3 and the values of rSO2 in the non-POCD group at t2 were found to be significantly higher than those at tl （P〈0.05）. The values of rSO2, %max in the POCD group were significantly higher than those in the non-POCD group （P〈0.05）. When the value of rSO2, %max is more than 10.1%, it may act as an early warning index for cognitive function changes, Conclusions： POCD after OLV may be associated with a decline in rSO2.

乌司他丁对术中单肺通气患者白介素-8的影响

背景与目的:乌司他丁是一种从健康男子尿液中提取的广谱水解酶抑制剂。目前尚未有乌司他丁对单肺通气时肺泡炎性反应是否有影响的研究。本研究拟观察肺叶切除术中患者单肺通气时肺泡白介素-8(IL-8)水平的改变,以及乌司他丁对单肺通气时肺泡IL-8的影响。方法:术中需行单肺通气肺叶切除术、ASAⅡ～Ⅲ级患者60例,随机分为术前使用5000u/kg乌司他丁的试验组(Ⅰ组)以及对照组(Ⅱ组),每组30例。在单肺通气开始、单肺通气1h、单肺通气2h、手术结束时分别进行支气管肺泡灌洗(bronchoalveolarlavage,BAL)。检测肺泡灌洗液中IL-8浓度水平,并观察其变化,进行统计学分析。结果:(1)对照组单肺通气2h后肺泡灌洗液中IL-8浓度水平为(160.85±46.58)ng/L,较单肺通气前犤(128.26±35.35)ng/L犦上升,表明单肺通气和/或手术刺激导致肺泡炎性反应;(2)试验组肺泡灌洗液中IL-8浓度水平在单肺通气2h以及手术结束分别为(140.32±41.25)ng/L、(156.74±43.58)ng/L,较对照组犤(134.48±40.51)ng/L、(160.85±46.58)ng/L、(172.41±52.60)ng/L犦明显降低,差异有统计学意义(P<0.05)。结论:乌司他丁能减轻单肺通气患者肺泡炎性反应。

单肺通气对胸科手术患者肺内分流和血气的影响

目的:观察静吸复合麻醉下单肺通气对肺内分流和血气的影响。方法:10例择期胸科手术患者,ASA～级,分别在单肺通气前1min(T1)、单肺通气30min(T2)、单肺通气结束前1min(T3)各时刻抽取动脉血和混合静脉血行血气分析,并根据血气分析结果计算肺内分流率(Qs/Qt)。结果:T2、T3时刻,肺内分流率较T1时刻显著增加,动脉血氧分压较T1时刻显著下降,T3时刻的动脉血氧分压较T2时刻有所回升。结论:单肺通气时肺内分流及血气将发生显著变化,总体上胸科手术行单肺通气是安全的。

老年食管癌患者单肺通气期间局部脑氧饱和度的变化及影响因素分析

目的研究老年食管癌患者开胸手术单肺通气期间局部脑氧饱和度(rSO_2)的变化及影响因素。方法随机选取20例年龄大于65岁,拟静吸复合全身麻醉下行左后外切口开胸食管癌根治术的患者,采用双腔支气管导管进行开胸后单肺通气(SLV)管理,应用脑氧饱和度监测仪监测从清醒状态到气管拔管阶段的脑氧饱和度变化,并观察记录脑电双频指数(BIS)和标准监测参数,在对应时间点进行血气分析。结果①清醒状态时测定局部脑氧饱和度(rSO_2)为66.5%±2.2%,麻醉诱导后侧卧位双肺通气时rSO_2为56.2%±2.6%,在SLV期间rSO_2降为50.4%±2.2%,拔管时rSO_2为62.2%±2.1%;在SLV期间,所有患者rSO_2下降≥18%,70%(14/20)的患者降幅超过20%,30%(6/20)的患者降幅超过25%;SLV期间rSO_2绝对值低于50%的患者占30%(6/20)。②rSO_2的降低与SLV时间、BIS值、SpO_2、MAP、体温、PaCO_2、PaO_2、Hct、Hgb、SaO_2等临床监测参数均无相关性。结论老年食管癌患者单肺通气期间均发生脑氧饱和度的降低,有30%的患者rSO_2绝对值低于50%;rSO_2的降低与常规临床监测参数间无明显相关性。

自制CPAP装置用于单肺通气对动脉氧分压及肺内分流的影响

目的观察自制持续气道正压通气（CPAP）装置用于单肺通气（OLV）对动脉血氧分压及肺内分流的影响。方法 40例择期肺叶切除术患者,ASAⅠ~Ⅱ级,随机分为CPAP组（A组）和肺萎陷组（B组）,每组20例。A组单肺通气时在患侧肺使用自制CPAP装置给予5cm H2O纯氧持续呼吸道正压通气,B组未予任何干预措施。分别于单肺通气前（T0）、单肺通气后30min（T1）、单肺通气后60 min（T2）测定动脉及混合静脉血进行血气分析,并根据公式计算肺内分流率（Qs/Qt）。结果两组T0时点PaO2相比较差异无统计学意义（P〉0.05）,T1、T2时点A组的PaO2均较B组高（P〈0.01）,而Qs/Qt两组间各时点对比差异均无统计学意义（P〉0.05）。结论单肺通气期间,在患侧肺使用该自制CPAP装置给予5 cm H2O CPAP,可增加动脉血氧分压,但对肺内分流无明显影响。

5%碳酸氢钠对单肺通气患者血气的影响

目的评价5％碳酸氢钠（NaHCO3）对开胸单肺通气（OLV）患者术中血气的影响。方法择期开胸手术患者60例。男44例，女16例。年龄18～65岁。体重55～80kg。随机等分3组。I组：空白对照；II组：5％NaHC0330mL；III组：5％NaHCO360mL。连续监测血压（BP）、心率（I-IR）、动脉氧饱和度（SpO2）等。3组均采用静吸复合麻醉，诱导静注芬太尼3μg/kg、丙泊酚1．5～2．0mg／kg、琥珀胆碱1．5mg／kg，维持吸入1．0％-2．0％异氟烷，持续输注瑞芬太尼0．1～0．2μg／（kg·min）和间断静注维库溴铵0．02～0．03mg／kg。OLV后应用5％NaHCO3（Ⅱ组：1mL/min；Ⅲ组：2mL/min），分别在麻醉前（T0）、麻醉诱导后双肺通气时（T1）、单肺通气30分钟时（T2）、手术完毕前双肺通气时（L）采外周动脉血1mL进行血气分析。结果麻醉后组内比较：SpO2、动脉氧分压（PaO2）、血氧饱和度（SaO2）和CL^-3组麻醉后均有升高，与T0比较（P〈0．05或P〈0．01）；pH值、碱剩余（BE）和K‘3组在麻醉后均有下降，与T0比较（P〈0．05或P〈0．01）。麻醉后同时间段组间比较：SaO2在T2时间段Ⅲ组比I组和Ⅱ组高（P〈0．05）；BE在T2时间段、T3时间段Ⅲ组比I组高（P〈0．05和P〈0．01）。Ⅲ组患者苏醒最快，与I组比较（P〈0．05）。结论Ⅲ组患者呼吸系统相对平稳，保持较高的SaO2，pH值和BE值下降幅度减小，苏醒迅速，有高氯代酸倾向，但是不会影响CO2的排除。