单肺通气模式下不同水平PEEP对肺损伤的影响

目的探讨单肺通气模式下不同水平呼气末正压通气(PEEP)对肺损伤的影响。方法选择拟单肺通气剖胸手术患者60例,随机分成三组,每组20例。A组单肺通气6 mL/kg+PEEP为0 cmH2O,B组单肺通气6mL/kg+PEEP为4 cmH2O,C组单肺通气6 mL/kg+PEEP为8 cmH2O,术中均为持续性单肺通气,并排除肺功能差或有肺部疾病者。通过监测单肺通气前(T1)、单肺通气30 min(T2)、单肺通气60 min(T3)、单肺通气90 min(T4)、单肺通气结束前(T5)、出室前(T6)的SpO2、MAP、HR。采集颈内静脉血5 mL进行肿瘤坏死因子(TNF-α)、IL-6检测。结果三组治疗不同时间点MAP、HR、SpO2无统计学差异(P均>0.05)。B、C两组从T3开始相对于A组炎性因子水平较低且有统计学差异(P均<0.05),而B、C两组间炎性因子水平比较无统计学差异(P均>0.05)。结论单肺通气6 mL/kg+PEEP 4 cmH2O对肺损伤影响最小。     

短暂高水平PEEP对压力控制通气ARDS患者氧合和血液动力学的影响

目的观察短暂高水平呼气末正压通气(PEEP)对急性呼吸窘迫综合征(ARDS)患者氧合情况及血流动力学的影响。方法 40例ARDS患者,随机分为实验组22例和对照组18例。实验组给予压力控制通气+短暂高水平PEEP促进肺复张,对照组仅给予压力控制通气。观察并比较两组患者的氧合及血流动力学变化。结果通气13、7、d后实验组患者PaO2/FiO2明显优于对照组(P均<0.05);通气17、d时实验组患者动脉血pH、PaCO2明显低于对照组(P均<0.05);通气1 d时实验组患者PaO2明显低于对照组(P<0.05)。两组患者通气1、2、3 d时HR、MAP、CVP相比,P均>0.05。结论短暂高水平PEEP可改善ARDS患者的氧合,对血流动力学无明显影响。     

不同单肺通气模式对肺癌手术病人氧合和肺内分流的影响分析

目的 评价不同单肺通气模式对肺癌手术患者氧合和肺内分流的影响.方法 选择行肺叶切除手术的肺癌患者50例,按随机数字表将其分为三组,分别采用不同单肺通气后通气模式,观察和比较各组不同时间点氧合和肺内分流参数的变化.结果 B组T2和T3时刻OI值,显著高于A组和B组（P〈0.05）,与T0时刻无显著差异（P〉0.05）;B组T1和T2时刻Qs/Qt值,显著高于A组、B组和T0时刻（P〈0.05）;T3时刻Qs/Qt值显著高于A组和B组（P〈0.05）,与T0时刻无显著差异（P〉0.05）.结论 呼吸频率17次/min,潮气量6 mg/kg和呼吸末正压5 cmH2O,能显著提高氧分压,减少肺内分流,减轻对肺的损伤,是肺癌手术病人较为理想的单肺通气模式.     

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 H_2O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(T_0)、单肺通气后30min(T_1)、单肺通气后60 min(T_2)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(P0.05),T_1、T2时点A组的PaO_2均较B组高(P0.01),而Qs/Qt两组间各时点对比差异均无统计学意义(P0.05)。结论单肺通气期间,在患侧肺使用该自制CPAP装置给予5 cm H_2O CPAP,可增加动脉血氧分压,但对肺内分流无明显影响。     

肺叶切除时患肺持续吹氧的观察

利用双腔管将两肺隔离 ,随时按需要单肺通气 ,是麻醉管理及手术的要求。问题在于单肺通气后引起的缺氧 ,而积极的预防和对症处理均可纠正和维持氧供。本文介绍在对患者肺叶切除时实施持续高流量吹氧的方法 ,预防效果确切。1　一般资料选择肺叶切除术患者 2 7例 ,男 2 1例 ,女 6     

全麻中潮气量变化对低水平PEEP肥胖患者呼吸功能的影响

目的研究肥胖患者全麻中行低水平呼气末正压通气（PEEP）时的适宜潮气量。方法将同期拟行仰卧位上腹部手术的30例肥胖患者随机分为A、B、C三组各10例,三组麻醉诱导和维持药物相同,术中均采用5cmH2O PEEP,潮气量分别为6、9、12ml/kg,呼吸频率为14次／min。监测各组在麻醉前（T1）、气管插管后30min（T2）、插管后60min（T3）、气管拔管后30min（L）、拔管后60min（L）循环及血气各指标变化。结果T2、L时,肺泡动脉血氧分压差（A—aDO2）、动脉血与呼气末二氧化碳分压差（Pa-∑TCO2）、气道峰压（Ppeak）A组〈B组〈C组,Pa·∑TCO2、PaCO2A组〉B组〉C组（P〈0．05或P〈0．01）;T4、T5时,B组PaO2较A、C组明显升高（P〈0．05）,而A、B组A-aDO2较C组明显降低（P〈0．05）;各组不同时间点MAP、HR、CVP均无显著差异。结论肥胖患者全麻中行低水平PEEP时的适宜潮气量为9ml／kg,其能维持全麻期间呼吸功能、改善全麻后低氧血症,且对血流动力学无明显影响。     

氟比洛芬酯对单肺通气下食管癌手术患者肺内分流及动脉氧合的影响观察

目的：探讨氟比洛芬酯对单肺通气下食管癌手术患者肺内分流及动脉氧合的影响。方法择期行胸食管癌根治术的患者60例,随机分为F组和C组各30例。在麻醉诱导前15 min,F组静脉给予氟比洛芬酯,C组给予等量生理盐水。于侧卧双肺通气5 min（ T1）、单肺通气30 min（ T2）和恢复双肺通气30 min（ T3）采集动静脉血样行血气分析并记录血流动力学指标,计算肺内分流率（ Qs／Qt ）。结果两组血液动力学指标、平均气道压（Pmean）、pH比较,差异无统计学意义（P均＞0．05）。与T1时比较,两组T2、T3时PaO2降低,Qs／Qt升高（P均＜0．05）;与T2时比较,两组T3时PaO2升高,Qs／Qt降低（P均＜0．05）;与C组比较,F组T2、T3时Qs／Qt降低,T3时PaO2升高（P均＜0．05）。结论麻醉前15 min静脉给予氟比洛芬酯可减少食管癌根治术患者单肺通气时肺内分流,提高动脉氧合。     

体重指数对COPD患者开胸手术单肺通气期间氧合和肺内分流的影响

目的探讨体重指数（BMI）对慢性阻塞性肺疾病（COPD）患者单肺通气（OLV）期间血液氧合及肺内分流的影响。方法24例择期开胸手术的COPD稳定期患者,根据BMI值分为低BMI组（Ⅰ组）和正常BMI组（Ⅱ组）,每组12例,分别于患者右侧卧双肺通气（TLV）10min、OLV10、20、30、40min抽取动、静脉血行血气分析并计算肺内分流率（Qs／Qt）。结果两组患者OLV各时点Pa02较TLV时明显下降（P〈0．05）,Qs／Qt明显增加（P〈0．05）;与Ⅱ组比较,Ⅰ组病人各时点Pa02、Qs／Qt均有明显差异（P〈0．05）。结论正常体重指数COPD患者较低体重指数COPD患者OLV期间具有更好的血液氧合趋势,肺内分流增加较少。     

双相气道正压通气治疗急性肺损伤的临床观察

目的探讨双相气道正压（BIPAP）通气模式对急性肺损伤（acute lung injury,ALI）患者的治疗作用。方法将20例接受机械通气治疗的Au患者随机分为容量控制通气组（VCV组）和双相气道正压通气组（BIPAP组）,每组各10例。观察两组血气分析、呼吸力学指标。结果通气后BIPAP组的氧分压（PaO2）、动脉血氧饱和度（SaO2）、氧合指数（OI）均显著高于VCV组（P〈0.05）;通气结束时,VCV组镇静剂用量和气管插管通气时间均显著高于BIPAP组（P〈0．05）。结论BIPAP通气模式人机协调性好,缩短了治疗时间。     

外源性呼气末正压对慢性阻塞性肺疾病患者呼吸功的影响

目的探讨外源性呼气末正压（PEEPe）对慢性阻塞性肺疾病（COPD）患者呼吸功的影响及其机制。方法选择接受气管插管和机械通气的COPD患者10例,使用BicoreCP-100呼吸力学监测仪进行呼吸力学监测。首先测定PEEPe为0时的动态内源性呼气末正压（PEEPi）,再以此值的0、40%、60%、80%和100%随机设置PEEPe;在每次改变PEEPe水平30min后,测定呼吸力学及心率、血压、动脉血气。结果患者的呼吸功、压力时间乘积、食管压差和动态PEEPi在加用PEEPe后即明显降低,且随着PEEPe的增加继续下降（P值均<0.01）。当PEEPe加至PEEPe=0时所测的动态PEEPi的80%和100%时,呼吸机做功显著增加（P值均<0.01）。呼吸功的变化和动态PEEPi的变化呈直线正相关关系（r=0.609,P<0.01）。结论PEEPe可降低呼吸功,并且是通过降低患者呼气末肺泡与中心气道之间的压力差来降低呼吸功的。     

正、负压通气对离体兔肺血流动力学和氧合效果的影响

目的 :运用离体兔肺灌流模型 （IPL ）比较正、负压两种通气对肺循环血流动力学及通气效果的影响。方法 :建立 18只肺负压通气 （NPV ）的 IPL模型 ,控制灌流液流量 （133.33m l/ m in）不变 ,在相同的潮气量及呼气末跨肺压下 ,对 12只 IPL更换为正压通气 （PPV ） ,2 0 min后重新进行 NPV。在两种通气下 ,测定灌流压力 （Pa）、回流压力（Pv）、气道压力 （Paw）、肺重量 （L Wt）等指标并连续同步描记。检测灌流液血氧分压 （Po2 ）值。另 6例 IPL一直行NPV.结果 :PPV可使 Pa、肺血管阻力增高 ,L Wt下降。 PPV吸气时 Pa增加 ,Pv下降 ,L Wt略有上升 ;NPV吸气时 Pa,Pv均下降 ,L Wt显着增加。 NPV时血氧增加幅度高于 PPV。结论 :本实验条件下 PPV导致肺血管阻力增加 ;NPV的氧合效果优于 PPV     

Acute effects of PEEP on tidal volume and respiratory center output during synchronized ventilation in preterm infants

BACKGROUND: Positive end expiratory pressure (PEEP) is routinely used in mechanically ventilated preterm infants to maintain lung volume. An acute increase in PEEP can affect lung mechanics and tidal volume, but it is unknown if these effects elicit compensatory changes in respiratory center output. OBJECTIVES: To investigate the acute effects of changes in PEEP on tidal volume (V(T)), lung compliance (C(L)), and respiratory center output (RCO) during synchronized intermittent mandatory ventilation (SIMV) in preterm infants at different levels of basal respiratory drive. METHODS: Preterm infants were studied during SIMV at three levels of PEEP (2, 4, and 6 cm H(2)O for 2-3 min each) and at two levels of inspired CO(2). Peak inspiratory pressure (PIP) was adjusted to maintain the same delta pressure at the airway. RCO was assessed by measuring total diaphragmatic electrical activity. The level of inspired CO(2) was adjusted by modifying the instrumental dead space. RESULTS: Sixteen preterm infants GA: 25 +/- 2 weeks, BW: 786 +/- 242 g, age: 18 +/- 15 days, SIMV: rate 14 +/- 3 b/min, Ti: 0.35 +/- 0.01 s, PIP: 16 +/- 1 cm H(2)O, and FiO(2): 0.31 +/- 0.06 were studied. At both levels of inspired CO(2), C(L), V(T), and V'(E) from spontaneous and mechanical breaths decreased significantly with higher PEEP. RCO did not change, but at lower respiratory drive, there was a trend towards an increase in RCO with higher PEEP. CONCLUSION: Higher PEEP levels can have acute negative effects on lung mechanics and ventilation in preterm infants without a sufficient compensatory increase in RCO.     

Individualized positive end-expiratory pressure (PEEP) during one-lung ventilation for prevention of postoperative pulmonary complications in patients undergoing thoracic surgery: A meta-analysis

Background:Positive end-expiratory pressure (PEEP) is an important part of the lung protection strategies for one-lung ventilation (OLV). However, a fixed PEEP value is not suitable for all patients. Our objective was to determine the prevention of individualized PEEP on postoperative complications in patients undergoing one-lung ventilation.Method:We searched the PubMed, Embase, and Cochrane and performed a meta-analysis to compare the effect of individual PEEP vs fixed PEEP during single lung ventilation on postoperative pulmonary complications. Our primary outcome was the occurrence of postoperative pulmonary complications during follow-up. Secondary outcomes included the partial pressure of arterial oxygen and oxygenation index during one-lung ventilation.Result:Eight studies examining 849 patients were included in this review. The rate of postoperative pulmonary complications was reduced in the individualized PEEP group with a risk ratio of 0.52 (95% CI:0.37–0.73; P = .0001). The partial pressure of arterial oxygen during the OLV in the individualized PEEP group was higher with a mean difference 34.20 mm Hg (95% CI: 8.92–59.48; P = .0004). Similarly, the individualized PEEP group had a higher oxygenation index, MD: 49.07mmHg, (95% CI: 27.21–70.92; P < .0001).Conclusions:Individualized PEEP setting during one-lung ventilation in patients undergoing thoracic surgery was associated with fewer postoperative pulmonary complications and better perioperative oxygenation.     

单肺通气方式对围术期炎性细胞因子的影响

目的观察单肺通气（OLV）方式对患者围术期炎性细胞因子影响。方法拟行肺叶切除术肺癌患者36例,随机分为长时间组（Ⅰ组）和间断的双肺通气组（Ⅱ组）,每组18例。两组患者分别在麻醉诱导后（T1）、OLV 45 min（T2）、90min（T3）及术后2h（T4）采取静脉血,测定血清肿瘤坏死因子-α（TNF-α）、白细胞介素（IL）-6、IL-8、IL-10浓度。结果两组TNF-α、IL-6、IL-8和IL-10于T2时明显上升（P〈0．05）,Ⅱ组T3、T4时TNF-α、IL-6和IL-8均明显低于Ⅰ组（P〈0．05）,而IL-10高于Ⅰ组（P〈0．05）。结论单肺通气期间间断双肺通气可减轻炎性反应。     

高吸气峰压诱发呼吸机所致肺损伤及呼气末气道正压的保护作用

目的:探讨呼气末气道正压(PEEP)对高吸气峰压(PIP)所致肺损伤的保护作用。方法:20只成年SD大鼠随机分成四组,每组5只,对照组手术完毕后处死,其余三组给予机械通气:1 P10组,设置吸气峰压值为(PIP,cm H2O)/频率(f,次/分)/吸呼比(I:E)/呼气末正压(PEEP,cm H2O)为10/40/1∶1/0;2 P50组,设置PIP/f/I∶E/PEEP为50/20/1∶1/0;3 PEEP组,设置PIP/f/I:E/PEEP为50/40/1;1/10,20分钟后处死。观察呼吸机潮气量(VT)、呼吸系统阻力(Rrs)和动态肺顺应性(Cdyn),测定动脉血氧分压(Pa O2)。实验结束后测定肺组织含气容积密度(VV)、肺髓过氧化物酶(MPO)和白细胞介素-8(IL-8)含量。结果:与P10组比较,P50组VT、Rrs、MPO和IL-8均显著增加(P0.05或P0.01),而Pa O2、Cdyn和VV显著降低(均P0.05);PEEP组上述各指标均显著优于P50组(P0.05或P0.01)。P10和对照组间上述指标均相近。结论:高气道压MV诱发明显VILI,加用PEEP可以保护肺结构和功能,减轻肺损伤。     

Lung function tests in neonates and infants with chronic lung disease: global and regional ventilation inhomogeneity

This review considers measurement of global and regional ventilation inhomogeneity (VI) in infants and young children with acute neonatal respiratory disorders and chronic lung disease of infancy (CLDI). We focus primarily on multiple-breath inert gas washout (MBW) and electrical impedance tomography (EIT). The literature is critically reviewed and the relevant methods, equipment, and studies are summarized, including the limitations and strengths of individual techniques, together with the availability and appropriateness of any reference data. There has been a recent resurgence of interest in using MBW to monitor lung function within individuals and between different groups. In the mechanically ventilated, sedated, and paralyzed patient, VI indices can identify serial changes occurring following exogenous surfactant. Similarly, global VI indices appear to be increased in infants with CLDI and to differentiate between infants without lung disease and those with mild, moderate, and severe lung disease following preterm birth. While EIT is a relatively new technique, recent studies suggest that it is feasible in newborn infants, and can quantitatively identify changes in regional lung ventilation following alterations to ventilator settings, positive end expiratory pressure (PEEP), and administration of treatments such as surfactant. As such, EIT represents one of the more exciting prospects for continuous bedside pulmonary monitoring. For both techniques, there is an urgent need to establish guidelines regarding data collection, analysis, and interpretation in infants both with and without CLDI.