滴定个体化呼气末正压对全麻俯卧位脊柱手术老年患者呼吸功能的影响

目的探讨滴定个体化呼气末正压(PEEP)对全麻俯卧位脊柱手术老年患者术中呼吸和循环的影响。方法选择择期全麻下行俯卧位脊柱手术老年患者80例,男39例,女41例,年龄≥65岁,ASAⅡ或Ⅲ级。根据术中是否滴定获取个体化PEEP将患者随机分为两组:滴定组和对照组,每组40例。滴定组从0 cmH_2O开始递增至20 cmH_2O,PEEP变化梯度为2 cmH_2O获取个体化PEEP;对照组PEEP恒定为5 cmH_2O并通气至手术结束。记录滴定过程中每个PEEP水平持续1 min时动态肺顺应性(Cdyn),将Cdyn最大时的PEEP定为个体化PEEP。记录俯卧位时(T_0)、PEEP通气10 min(T_1)、30 min(T_2)、60 min(T_3)、手术结束(T_4)、拔管后20 min(T_5)的MAP、HR、CVP,记录T_0—T_4时平均气道压(Pmean)和Cdyn。T_0—T_5时行血气分析,计算肺内分流率(Qs/Qt)和氧合指数(OI)。记录机械通气过程中去氧肾上腺素使用和术后肺部并发症情况。结果滴定组所获取的个体化PEEP为(12.38±2.67)cmH_2O。T_0—T_5时两组MAP、HR、CVP差异无统计学意义。T_0—T_4时两组Pmean差异无统计学意义。T_2—T_4时滴定组Cdyn明显高于对照组(P0.05),Qs/Qt明显低于对照组(P0.05)。T_2—T_5时滴定组OI明显高于对照组(P0.05)。滴定组去氧肾上腺素使用率明显高于对照组[10例(25%) vs 3例(8%),P0.05]。滴定组术后肺部并发症发生率明显低于对照组[2例(5%) vs 8例(20%),P0.05]。结论与恒定PEEP 5 cmH_2O比较,俯卧位脊柱手术老年患者术中滴定个体化PEEP,能够更好地改善氧合,降低肺内分流率,减少术后肺部并发症。     

呼气末正压通气对腹腔热灌注化疗患者呼吸力学及肺功能的影响

目的探讨不同呼气末正压通气对腹腔热灌注化疗患者呼吸力学及肺功能的影响。方法选择择期行腹膜癌热灌注化疗的患者90例,男55例,女35例,年龄40~70岁,ASAⅠ~Ⅲ级。随机分为三组,每组30例。A组为容量控制通气(VCV)组,VT10 ml/kg;B组为VCV+低PEEP组,VT6ml/kg,PEEP 5cm H_2O;C组为VCV+高PEEP组,VT6ml/kg,PEEP 10cm H_2O;术中调整RR维持PETCO2 35~45 mm Hg。于气管插管后5 min(T_1)、腹腔热灌注化疗开始前(T2)、化疗结束时(T_3)、气管拔管前(T4)记录气道峰压(Ppeak)、气道平台压(Pplat)和平均气道压(Pmean),计算动态肺顺应性(C_(dyn))。并取桡动脉血进行血气分析,计算氧合指数(OI)、呼吸指数(RI)、肺泡-动脉血氧分压差(A-aDO_2)及死腔率(VD/VT)。记录术后7d内肺部相关并发症情况。结果与A组比较,T_1~T_4时B、C组Ppeak、Pplat、A-aDO_2和RI明显降低,OI和VD/VT明显升高(P0.05);T_2~T_4时B、C组Pmean明显降低,Cdyn和PaO_2明显升高(P0.05)。与T_1比较,T_2~T_4时A组Ppeak、Pplat和Pmean明显升高,C_(dyn)明显降低(P0.05);T_3时B组Ppeak和Pplat明显升高(P0.05),T_2~T_4 Pmean明显升高(P0.05),T3、T4时C_(dyn)明显降低(P0.05);T_2~T_4时C组Ppeak、Pplat和Pmean明显升高(P0.05),T_3、T_4时Cdyn明显降低(P0.05)。与T0时比较,T2~T4时三组PaO_2和OI明显降低,A-aDO_2、RI和VD/VT明显升高(P0.05)。术后7d内B、C组肺部感染、低氧血症和肺不张的发生率明显低于A组(P0.05)。结论小潮气量(6ml/kg)联合PEEP(5cm H_2O)通气可以显著改善腹膜癌患者术中热灌注期间肺功能,降低围术期肺部并发症的发生风险。     

呼气末正压通气对腹腔镜宫颈癌根治术患者眼压和视神经鞘直径的影响

目的观察腹腔镜下宫颈癌根治术中,5 cmH_2O的呼气末正压通气(PEEP)对患者眼内压(IOP)和颅内压的影响。方法选择我院择期行腹腔镜下宫颈癌根治术的患者60例,年龄45～65岁,BMI 20～25 kg/m~2,ASAⅠ或Ⅱ级。采用随机数字表法分为两组,PEEP为5 cmH_2O组(PEEP组)和无PEEP组(ZEEP组),每组30例。两组均采用静脉麻醉诱导气管插管,诱导完成机械通气后,PEEP组设置呼气末正压为5 cmH_2O,ZEEP组呼气末正压设置为0。记录麻醉诱导前(T_0)、麻醉后气腹前10 min平卧位(T_1)、气腹Trendelenburg体位后5 min(T_2)、30 min(T_3)、恢复平卧位气腹消失后(T_4)和术后30 min(T_5)时的IOP、视神经鞘直径(ONSD)、PaO_2、PaCO_2,同时记录T_1—T_4时肺动态顺应性(Cdyn)、气道峰压(Ppeek)和T_0—T_5时HR和MAP。结果与T_0时比较,T_1时两组IOP明显降低(P0.01),T_2—T_3时IOP明显延长(P0.01),T_2—T_3时ZEEP组ONSD明显延长(P0.01),T_3时PEEP组ONSD明显延长(P0.05)。T_1—T_4时PEEP组PaO_2、Cdyn明显高于ZEEP组(P0.05)。T_1时PEEP组Ppeek明显高于ZEEP组(P0.05)。结论在腹腔镜宫颈癌根治术手术中,气腹和Trendelenburg体位下应用5 cmH_2O的PEEP改善患者氧合的同时不引起IOP和颅内压的增高。     

肥胖患者腹腔镜结直肠癌根治术中实时食管压监测下呼气末正压通气对肺通气的影响

目的探讨实时食管压监测指导下设定呼气末正压(positive end expiratory pressure,PEEP)通气参数对肥胖腹腔镜结直肠癌根治术患者的临床价值。方法选择2016年1—12月收治的拟行腹腔镜结直肠癌根治术的肥胖患者90例,男50例,女40例,年龄40~65岁,BMI30kg/m2,ASAⅡ或Ⅲ级,采用随机数字表法将患者随机分为三组:P组、PEEP5组和PEEP10组,设置VT8ml/kg,分别在肺复张后给予个体化PEEP(采用实时食管压监测通过计算呼气末跨肺压=0cmH_2O和吸气末跨肺压=25cmH_2O确定最佳PEEP)、PEEP 5cmH_2O和10cmH_2O。观察气腹建立前(T0)、气腹建立后10min(T1)、气腹后头低40.5°足高位20 min(T2)和气腹结束(T3)时的呼吸力学指标。结果T1—T3时P组Ppeak、SBP明显低于,PaO_2/FiO_2明显高于PEEP5组和PEEP10组(P0.05);T2时P组Pplat、Raw明显低于PEEP5组(P0.05);T2、T3时P组Cst明显高于PEEP5组(P0.05);T1、T2时P组DBP明显低于PEEP5组和PEEP10组(P0.05)。结论实时食管压监测应用于PEEP通气的肥胖腹腔镜结肠癌手术患者,能够有效改善患者呼吸和循环功能。     

肺保护性通气策略对腹腔镜胃癌根治手术老年患者肺氧合功能及术后肺部并发症的影响

目的探讨肺保护性通气策略(lung protective ventilation strategy,LPVS)对腹腔镜胃癌根治手术老年患者肺氧合功能及术后肺部并发症(postoperative pulmonary complications,PPCs)的影响。方法选择接受腹腔镜胃癌根治手术的老年患者115例,男69例,女46例,年龄≥65岁,ASAⅠ—Ⅲ级,随机分为两组:常规容量控制通气组(CV组,n=57)和肺保护性通气组(PV组,n=58)。记录插管后10 min(T_1)、气腹后10 min(T_2)、气腹后60 min(T_3)、气腹结束10 min(T_4)时的气道峰压(Ppeak),计算肺顺应性(Cdyn),并在T_1—T_4时抽取动脉血进行血气分析,计算氧合指数(OI)、肺泡动脉血氧分压差(A-aDO_2);记录术后第2天改良肺部感染评分(mCPIS);记录术后7 d内PPCs发生情况。结果与T_1时比较,T_2时两组Cdyn均明显降低(P0.05);T_3—T_4时PV组Cdyn明显高于CV组(P0.05);T_3—T_4时PV组OI明显高于CV组、A-aDO_2明显低于CV组(P0.05)。术后第2天PV组mCPIS明显低于CV组(P0.05)。术后7 d内PV组PPCs发生率明显低于CV组(P0.05)。结论肺保护性通气策略能明显改善老年腹腔镜胃癌根治手术老年患者的肺氧合功能,降低术后肺部并发症,具有一定的肺保护作用。     

肺保护性通气在老年患者腹腔镜子宫内膜癌根治术中的应用

目的探讨肺保护性通气在老年患者腹腔镜子宫内膜癌根治术中的应用效果。方法选择2019年6月至2020年6月择期行腹腔镜子宫内膜癌根治术的老年女性患者60例,年龄65～80岁,BMI 20～28 kg/m~2,ASAⅠ或Ⅱ级。采用随机数字表法将患者分为两组:肺保护性通气组(P组)和常规机械通气组(R组),每组30例。P组设置V_T 7 ml/kg、呼气末正压通气(PEEP) 7 cmH_2O、每30分钟规律手法肺复张一次;R组仅设置V_T 9 ml/kg,未采用PEEP和肺复张。记录气腹前即刻、气腹后2 h、手术结束即刻的气道峰压(Ppeak)、气道平台压(Pplat)、肺动态顺应性(Cdyn)及血清IL-6、IL-8、TNF-α浓度。记录气腹前即刻和出复苏室即刻的氧合指数(PaO_2/FiO_2)。结果与气腹前即刻比较,气腹后2 h、手术结束即刻两组Pplat、Ppeak及血清IL-6、IL-8、TNF-α浓度均明显升高(P0.05),Cdyn明显降低(P0.05);出复苏室即刻两组PaO_2/FiO_2明显降低(P0.05)。与R组比较,P组气腹后2 h、手术结束即刻Pplat、Ppeak及血清IL-6、IL-8、TNF-α浓度明显降低(P0.05),Cdyn明显升高(P0.05);出复苏室即刻PaO_2/FiO_2明显升高(P0.05)。结论肺保护性通气可以减轻老年患者腹腔镜子宫内膜癌根治术围术期呼吸功能损伤和炎症反应,可安全用于老年患者腹腔镜子宫内膜癌根治术。     

肺超声评分评价肺保护性通气策略对老年开腹手术患者肺损伤的影响

目的通过肺超声评分探讨肺保护性通气策略减轻老年开腹手术患者肺损伤的作用。方法选择2019年8月至2020年6月择期开腹手术患者50例,男33例,女17例,年龄65～80岁,BMI 18～25 kg/m~2,ASAⅠ—Ⅲ级。采用随机数字表法将患者分为两组:对照组(C组)和肺保护性通气组(P组),每组25例。所有患者常规麻醉诱导,采用容量控制的通气模式。C组设置V_T 8 ml/kg,不使用呼气末正压(PEEP);P组设置V_T 6 ml/kg, PEEP 6 cmH_2O,每间隔30 min给予手法肺复张。采用床旁超声评估患者双侧共12个区域的肺部超声,各区域分数累积为肺超声评分(LUS)。记录入室时(T_0)、麻醉诱导气管插管后5 min(T_1)、手术开始后2 h(T_2)、手术结束时(T_3)、气管导管拔除后15 min(T_4)、2 h(T_5)、术后1 d(T_6)的LUS评分、HR、MAP、SpO_2、PaO_2和PaCO_2。记录T_1—T_3时的氧合指数(PaO_2/FiO_2)、气道峰压(Ppeak)、吸气末平台压(Pplat)和驱动压力(ΔP)。记录术后7 d内肺部并发症(PPCs)的发生情况。结果与T_0时比较,T_1—T_5时C组和P组LUS评分明显升高(P0.05)。与T_1时比较,T_2—T_3时C组PaO_2/FiO_2明显降低(P0.05),P组ΔP明显降低(P0.05)。与C组比较,P组T_2—T_5时LUS评分明显降低(P0.05),T_2—T_3时PaO_2/FiO_2明显升高(P0.05)、ΔP明显降低(P0.05)。C组术后7 d内PPCs发生率为20%,P组未发生PPCs(P0.05)。结论床旁肺超声监测下,老年开腹手术患者在全麻期间和术后早期LUS评分升高,肺通气丢失。肺保护性通气策略可降低患者围术期的肺超声评分,减少肺通气损失,降低术后7 d的肺部并发症发生率。     

不同通气模式对老年患者腹腔镜结直肠手术呼吸参数的影响

目的观察小潮气量容量控制通气(VCV)联合呼气末正压通气(PEEP)和压力控制通气(PCV)联合PEEP对老年患者呼吸参数的影响。方法选择行腹腔镜直肠、乙状结肠手术患者51例,男25例,女26例,年龄65~80岁,BMI 18~30kg/m2,ASAⅠ或Ⅱ级,随机分为两组:VP组(VCV+PEEP)和PP组(PCV+PEEP),每组25例。气腹期间VP组以VT6 ml/kg+5cmH2O PEEP模式通气,PP组将VT设为6 ml/kg通气3 min后切换为PCV并加用5cmH2O PEEP进行通气。记录气管插管VCV通气5min(T1)、建立人工气腹5 min(T2)、建立人工气腹35min(T3)、建立人工气腹65min(T4)、手术结束(T5)、拔管前(T6)时VT、动态肺顺应性(Cdyn)、RR、气道峰压(Ppeak)、气道平台压(Pplat)和PETCO2。记录T1、T3、T4和离开PACU(T7)时PaO2、PaCO2,并计算肺泡-动脉血氧分压差(PA-aDO2)、氧合指数(OI)、呼吸指数(RI);记录术后5d内肺部并发症(PPCs)情况。结果与VP组比较,T2-T4时PP组VT明显升高、Cdyn明显增大(P0.05),T3-T5时PP组RR明显减慢(P0.05),T2-T5时PP组Ppeak和Pplat明显降低(P0.05),T4时PP组PETCO2和PA-aDO2明显降低、PaO2明显升高、RI明显减小、OI明显增大(P0.05)。术后随访两组患者PPCs差异无统计学意义。结论PCV联合PEEP通气模式明显降低Ppeak和Pplat、增高VT和增大Cdyn,同时明显改善气腹65min时肺氧合功能,所以老年患者腹腔镜结直肠手术术中应优先考虑使用。     

最佳呼吸末正压肺保护通气策略对腹腔镜下结直肠癌根治术患者氧合功能的影响

目的探讨最佳呼吸末正压(PEEP)肺保护通气策略对腹腔镜下结直肠癌根治术患者围术期氧合功能的影响。方法择期行腹腔镜下结直肠癌根治术患者54例,男36例,女18例,年龄65～85岁,ASAⅡ或Ⅲ级。随机分为两组:传统组(T组)和保护组(P组),每组27例。T组设置V_T 9 ml/kg且无PEEP和肺复张(RMs);P组通过肺动态顺应性(Cdyn)PEEP滴定确定患者最佳PEEP值,设置低V_T 7 ml/kg联合最佳PEEP,每30分钟RMs一次。于麻醉诱导后10 min(T_1)、每次RMs后30 min(T_2、T_3、T_4)记录Cdyn及气道平台压(Pplat)、并在T_1—T_4、拔管后30 min(T_5)及术后第3天(T_6)采集动脉血样本,计算氧合指数(OI),记录术前和T_6时的改良临床肺部感染评分(mCPIS)。结果与T组比较,T_3、T_4时P组Cdyn明显升高(P0.05),T_4—T_6时P组OI明显升高(P0.05),T_6时P组mCPIS明显降低(P0.05)。结论最佳PEEP联合低V_T和RMs的肺保护通气策略可改善腹腔镜结直肠癌根治术患者围术期氧合,降低mCPIS。     

甲基强的松龙对肺叶切除术患者单肺通气时肺功能和炎症反应的影响

目的探讨甲基强的松龙(甲强龙)对肺叶切除术患者单肺通气时肺功能和炎症反应的影响。方法选择择期拟行肺叶切除术患者60例,男46例,女14例,年龄18~60岁,ASAⅠ或Ⅱ级,采用随机数字表法分为两组:甲强龙组(M组)和对照组(C组),每组30例。M组于麻醉诱导前30min静脉注射甲强龙2mg/kg,C组于相同时点静脉注射等量生理盐水。分别记录单肺通气前(T_0)、单肺通气30min(T_1)、单肺通气1h(T_2)、恢复双肺通气10min(T_3)及术毕(T_4)时的MAP、气道峰压(Ppeak)、气道平台压(Pplat)及动态肺顺应性(Cdyn),并于上述时间点抽取桡动脉血行血气分析,检测PaO_2和PaCO_2,计算氧合指数(OI)、肺泡-动脉血氧分压差(A-aDO_2)及呼吸指数(RI)。分别于T_0、T_4、术后6h(T_5)及术后24h(T_6)采集中心静脉血样,采用ELISA法检测血清TNF-α、IL-6及IL-10的浓度。记录术后72h肺部并发症的发生情况。结果与T_0时比较,T_1、T_2时两组MAP、Cdyn明显降低,Ppeak、Pplat明显升高(P0.05);T_1~T_4时OI明显降低,A-aO_2、RI明显升高(P0.05);T_4~T_6时血清TNF-α、IL-6及IL-10浓度明显升高(P0.05)。与C组比较,T_1、T_2时M组Ppeak、Pplat明显降低,Cdyn明显升高(P0.05);T_4~T_6时M组血清TNF-α、IL-6浓度明显降低,IL-10浓度明显升高(P0.05)。两组患者术后72h肺部并发症发生率差异无统计学意义。结论甲强龙可有效改善肺叶切除术患者单肺通气时动态肺顺应性,优化呼吸动力学,减轻机体炎症反应,但对肺氧合及换气功能无明显影响。     

股静脉测压法和膀胱测压法在危重患者腹内压监测中的比较

目的：比较股静脉测压法和膀胱测压法在危重患者腹内压（IAP）监测中的应用价值.方法：对2013年1-6月住院治疗的20例ICU重症患者,分别使用两种测压方法进行IAP监测,均每8 h 1次,连续测定3 d,每次随机选择两种方法的测量顺序,共测量720次,比较两种测压法在读数精准性、测压数值、操作时间、并发症和医护人员满意度等方面的异同.结果：股静脉测压法所测压力数值与膀胱测压法相近[（14.14±4.33）mmHg比（12.91±4.75）mmHg,P〉0.05];但是股静脉测压法的操作时间[（57.94±19.00）s]较膀胱测压法更短[（112.49±27.07）s,P〈0.05];股静脉测压法读数精准率（84.44%）较膀胱测压法（49.44%）高（P〈0.01）,操作并发症低至1.1%（4例次）,远低于膀胱测压法的5.3%（19例次,P〈0.05）;医护人员满意度达（3.90±0.26）分,优于膀胱测压法[（2.48±0.19）分,P〈0.01].结论：相对于膀胱测压法而言,股静脉测压法具有测压值相似、操作时间短、读数精准度高、操作并发症少、接纳度高等优点,值得在危重患者IAP监测中推广.     

Clinical evaluation of a simple epidural pressure sensor

Summary The Plastimed^® epidural pressure sensor was evaluated in 35 patients, twenty-eight of whom were suffering from head injury. In seven patients simultaneous intraventricular pressure measurements were obtained. The epidural pressure sensor was only functioning satisfactorily in approximately 2/3 of the patients, while it was malfunctioning or not functioning in the remainder. In seven comparable IVP/EDP studies significant differences up to 25 mm Hg were noted. In three patients IVP was greater than EDP. In two patients the opposite was true. No significant complications were observed.These unsatisfactory results have made us abandon the technique and resort to intraventricular or subarachnoidal pressure measurements.     

Clinical evaluation of a new epidural pressure monitor

Summary Comparative measuring of epidural pressure using the Spiegelberg probe 1 and ventricular fluid pressure was carried out in 15 neurosurgical intensive-care patients. Deviations in both directions were established, with a trend toward overestimating ventricular pressure in epidural pressure measuring (r=0.77). Individual pulsations, spontaneous wave courses and therapy-induced pressure changes were reflected without delays. There were no complications observed with probe implantation periods for up to 6 days. The system has been shown to be mechanically stable and easy to implant. We believe the device to be fit for trend monitoring of intracranial pressure. As with other epidural pressure monitoring systems, false assessments of ventricular pressure may lead to wrong decisions as to the required therapy.     

The Rotterdam teletransducer: State of the device

Summary The developments of a telemetric device for monitoring intracranial pressure, the Rotterdam Teletransducer, are described. The major problem in telemetric pressure sensing devices consists of diffusion of water into the transducer, resulting in unpredictable zero drift. Therefore, special attention was paid to bonding techniques for sealing the transducer.The results of improved epoxy sealing, active metal brazing and glass bonding are described. In vitro tests showed transducers sealed with epoxy resin to be stable for two months. Using the more complicated tchniques of glass bonding and active metal brazing, hermetic seals could be achieved with stable transducers for over one year. In vivo functioning of the Rotterdam Teletransducer was tested in acute and chronic animal experiments. The in vivo results corresponded to those obtained in the in vitro experiments. Regression analysis between epidural and ventricular fluid pressure showed a one to one ratio.Results of clinical application of the device in 22 patients are described. Accurate depth setting of the transducer on the dura, according to the pressure depth curve, was shown to be essential.The device has also been used with success for non-invasive fontanelle pressure measurements in infants. The depth positioning of the transducer on the fontanelle according to a pressure depth curve is described.This paper has been awarded by the 1985 Casey Holter Memorial Prize by the Society for Research in Hydrocephalus and Spina Bifida.     

Idiopathic normal pressure hydrocephalus: Analysis of factors related to cerebrospinal fluid dynamics determining functional prognosis

Summary This investigation has been undertaken to analyze the findings with both the cerebrospinal fluid (CSF) pressure (Pcsf) and CSF pulse pressure (PP) in order to predict the outcome of patients with the syndrome of idiopathic normal pressure hydrocephalus (NPH). Accordingly, a prospective clinical study was planned in which two groups of patients with NPH, having analogous prevalence of several matched clinical and radiological parameters, were separated on the basis of their positive or negative response to shunting. Both the resting Pcsf and CSF PP profiles were compared in these two groups, and between them and normal controls. CSF PP amplitude and CSF PP latency correlated directly in conditions associated with either normal or high compliance (controls and patients with Alzheimer-like disorders), whereas this correlation was inverse in states of low compliance (NPH). On the other hand, shunt-responders showed a resting Pcsf significantly higher than both non-responders and controls.The following conclusions were obtained: 1) CSF PP is a high-amplitude and relative low-latency wave in NPH when compared with controls; 2) CSF PP amplitude and latency correlate directly in normal subjects and in those with primary cerebral atrophy; 3) a non-reversible stage of NPH could be conceived in contradistinction to the reversible one, in both of which an inverse correlation between the amplitude and the latency takes place, the main difference between them being the resting Pcsf, which is significantly lower in the former than in the latter, depending on the degree of atrophic changes developed.     

膀胱压、胃内压与腹内压的相关性研究

目的 探讨利用膀胱压、胃内压来间接监测腹内压的可行性．以便于腹腔间隔室综合征(ACS)的诊断。方法 对24例行腹腔镜胆囊摘除术(LC)患者进行前瞻性对照研究。在行LC时，在腹内压为10、15、20及25mmHg时同时测定膀胱压和胃内压。结果 腹内压与膀胱压的回归方程为Y=-10.193 1.228X．相关系数为0.941；腹内压与胃内压的回归方程为Y=-7.408 1.478X，相关系数为0.996。由此表明．腹内压与膀胱压和胃内压呈显著正相关。结论 腹内压与胃内压和膀胱压有很好的相关性，可以利用胃内压和膀胱压来反映实际腹内压。     

间歇正压通气和呼气末正压通气对犬眼内压的影响

目的 探讨间歇正压通气(IPPV)和呼气末正压通气(PEEP)对犬眼内压(10P)的影响.方法 实验犬8只,麻醉后分别监测基础条件下和各种机械通气条件下的IOP、CVP、MAP.结果 实施20 ml/kg和30 ml/kg两种不同潮气量的IPPV时IOP差异无统计学意义.实施10、15、20cm H20三种不同压力值的PEEP时IOP均显著升高(P<0.01).结论 IPPV对IOP影响不大,PEEP可使IOP显著升高.     

Telemetric recording of intrapleural pressure

BACKGROUND: Monitoring of intrapleural pressure (IPP) is used for evaluation of lung function in a number of pathophysiological conditions. We describe a telemetric method of non-invasive monitoring of the IPP in conscious animals intermittently or continuously for a prolonged period of time. MATERIALS AND METHODS: After IACUC approval, six mongrel dogs were used for the study. After sedation, each dog was intubated and anesthetized using 0.5% Isoflurane. A telemetric implant model TL11M2-D70-PCT from Data Science International was secured subcutaneously. The pressure sensor tip of the catheter from the implant was inserted into the pleural space, and the catheter was secured with sutures. The IPP signals were recorded at a sampling rate of 100 points/second for 30 to 60 min daily for 4 days. From these recordings, the total mean negative IPP (mmHg), and the total mean negative IPP for a standard time of 30 min were calculated. In addition, the actual inspiratory and expiratory pressures were also measured from stable recording of the IPP waveforms. RESULTS: In six dogs, the total mean +/- SD negative IPP was -10.8 +/- 10.6 mmHg. After normalizing with respect to acquisition time it was -13.2 +/- 11.2 mmHg/min. The actual inspiratory pressure was -19.7 +/- 15.3, and the expiratory pressure was -11.0 +/- 12.9. CONCLUSIONS: Our study demonstrates that telemetric monitoring of IPP can be performed reliably and non-invasively in conscious experimental animals. The values for IPP in our study are compatible with the results of other investigators who used different methods of IPP measurement. Further work may show this method to be helpful in understanding the pathophysiology of various breathing disorders.     

Iliac venous pressure estimates central venous pressure after laparotomy

Background

Central venous pressure (CVP) is traditionally obtained through subclavian or internal jugular central catheters; however, many patients who could benefit from CVP monitoring have only femoral lines. The accuracy of illiac venous pressure (IVP) as a measure of CVP is unknown, particularly following laparotomy.

Methods

This was a prospective, observational study. Patients who had both internal jugular or subclavian lines and femoral lines already in place were eligible for the study. Pressure measurements were taken from both lines in addition to measurement of bladder pressure, mean arterial pressure, and peak airway pressure. Data were evaluated using paired t-test, Bland-Altman analysis, and linear regression.

Results

Measurements were obtained from 40 patients, 26 of which had laparotomy. The mean difference between measurements was 2.2 mm Hg. There were no significant differences between patients who had laparotomy and nonsurgical patients (P = 0.93). Bland-Altman analysis revealed a bias of 1.63 ± 2.44 mm Hg. There was no correlation between IVP accuracy and bladder pressure, mean arterial pressure, or peak airway pressure.

Conclusions

IVP is an adequate measure of CVP, even in surgical patients who have had recent laparotomy. Measurement of IVP to guide resuscitation is encouraged in patients who have only femoral venous catheter access.     

防压疮气垫床压力选择的实证研究与分析

目的探讨临床防压疮气垫床的最佳压力。方法在改装设备测量气垫床压力和骶尾部压力的基础上,采用重复测量方法,选择76名健康志愿者仰卧于气垫床上,气垫床压力由充满逐渐降低,每降低5mmHg记录1次骶尾部压力;使用混合效应二次曲线模型分析气垫床压力与骶尾部压力的关系,通过固定效应确定最佳的气垫床压力,并根据个体随机效应分析气垫床压力的最佳范围。结果气垫床压力和骶尾部压力呈二次项分布,可以采用混合效应二次曲线模型进行分析;通过固定效应分析可得气垫床的最佳压力为24.55mmHg,根据个体随机效应分析可得气垫床的压力范围在20.23~29.40mmHg时,人体骶尾部所受的压力最低,与其他范围相比差异具有统计学意义(均P0.01)。结论气垫床最佳压力范围为20.23~29.40mmHg。