肺复张结合肺保护通气对肝移植术后肺损伤换气功能的影响

目的探讨肺复张结合肺保护通气策略对肝移植术后ALI或ARDS早期换气功能、血流动力学的影响。方法肝移植术后合并ALI者18例，其中6例发展为ARDS，给予25cm H2O气道压力及PEEP 17 cm H2O通气2min，扩张已萎陷实变的肺泡，并用适当的PEEP预防肺泡闭塞，保持肺泡复张。结果18例病人肺复张后氧分压、氧饱和度及吸氧分数均有明显改善，除1例肺部严重感染病人肺复张后吸氧分数仅上升40％，余17例均对肺复张反应良好。复张后平均氧分压上升68mmHg，平均氧饱和度上升9．5％，平均吸氧分数上升104．66％，改善的氧合可维持2～24h。肺复张结合肺保护通气策略纠正低氧血症的有效率为94．4％。病人对肺复张的耐受性佳，无明显并发症。结论肺复张结合肺保护通气策略是治疗肝移植术后ALI或ARDS的安全有效措施。     

小潮气量结合肺复张术对食管癌开胸术后早期急性呼吸窘迫综合征患者的疗效

目的 观察小潮气量(VT)结合肺复张术对食管癌开胸术后早期急性呼吸窘迫综合征(ARDS)患者的疗效与可能出现的不良反应.方法 2007年1月1日至2009年9月30日收治食管癌开胸术后早期ARDS患者26例,男性20例,女性6例;年龄51～76岁,平均65.5岁.患者术后循环稳定,因ARDS而不能脱离机械通气.监测并持续记录无创血压、脉搏氧饱和度,实行小VT通气结合呼吸末正压(PEEP)递增法进行肺复张.记录肺复张前及两次肺复张后30 min的PEEP水平及吸入氧浓度(FiO2);监测静态肺顺应性(CLS)及动脉血气分析.结果 26例患者共实施肺复张术52次,全部患者在肺复张术后,FiO2减低,CLS增加,动脉血气分析改善.所有病例均顺利出院,未发生气压伤或其他并发症.结论 小VT结合肺复张策略可以有效改善食管癌开胸术后早期ARDS患者的低氧血症.     

利用动态肺顺应性设定呼气末正压在胸腔镜肺叶切除术中的运用

目的 探讨单肺通气利用动态肺顺应性设定呼气末正压通气(positive end-expiratory pressure,PEEP)的优势及可行性. 方法 选择预行右侧肺叶切除患者80例,完全随机分为A组和B组,每组40例:A组,单肺通气实施肺膨胀(sustained inflation,SI)复张后加用20 cmH2O(1 cmH2O=0.098 kPa)的PEEP并递减滴定,随后以得到最大肺顺应性的PEEP值通气,直到恢复双肺通气;B组,通气PEEP值固定为5 cmH2O,其他通气方法同A组.记录患者血气、呼吸等参数. 结果 两组设定的PEEP值[A组(9.2±1.2) cmH2O,B组5 cmH2O]差异有统计学意义(P＜0.05);在单肺通气1 h(T3)、手术结束(T4)时,两组动脉血氧分压(partial pressure of oxygen,PaO2)比较,差异有统计学意义(P＜0.05);B组的PaO2在T3～T4逐步降低,差异有统计学意义(P＜0.05),而A组则维持较好(P＞0.05);T3、T4时刻A组的动态肺顺应性[(30.8±5.9)、(30.7±6.4) ml/cmH2O]与B组[(26.6±5.5)、(26.4±5.2) ml/cmH2O]比较,差异有统计学意义(P＜0.05). 结论 胸腔镜肺叶切除术中的单肺通气,利用动态肺顺应性设定的PEEP值通气能够得到更好的氧合及呼吸参数,并且维持较好.     

肥胖患者单肺通气期间的通气策略

背景 肥胖人群比例不断升高,肥胖影响正常生理功能,给麻醉带来不少问题,尤其在单肺通气(one-lung ventilation,OLV)过程中. 目的 减少肥胖患者OLV过程对预后转归的影响,降低肥胖患者围手术期呼吸系统并发症的发生率. 内容 探讨肥胖患者围手术期OLV期间的通气策略,包括通气模式的选择、保护性通气策略、高碳酸血症、肺泡复张策略和吸氧浓度的选择. 趋向 肥胖患者OLV期间采用小潮气量联合呼气末正压通气(positive end-expiratory pressure, PEEP)、间断肺泡复张和低到中度Fi02等通气策略有助于改善氧合、降低肺不张发生率,高碳酸血症在无肺部疾病患者中是否具有肺保护作用尚待研究.     

胸科手术的单肺通气策略

背景 在胸科手术的麻醉中进行单肺通气(one-lung ventilation,OLV),不但可以为手术提供良好的术野,而且可以隔离并保护肺脏.但是,这是一种非生理状态下的通气方式,OLV期间的气压伤和氧毒性等因素常导致机械通气相关性肺损伤(ventilator-induced lung injury,VILI). 目的 探讨适合胸科手术的OLV策略. 内容 在OLV期间,采用肺泡复苏策略(alveolar recruitment strategy,ARS)和“小潮气量+呼气末正压通气(positive end-expiratory pressure,PEEP)”的保护性通气策略,使吸气平台压(plateau pressure,Pplat)＜25 cmH2O(1 cmH2O=0.098 kPa)和气道峰压(peak inspiratory pressure,Ppeak)＜35 cmH2O;限制FiO2;依据动脉血气分析的结果,酌情调整呼吸频率. 趋向 在OLV期间,应避免肺泡的过度膨胀和循环性的萎陷-复张,避免高浓度氧导致氧化应激加重,可以接受短时间内的高碳酸血症.对患者进行个体化管理,降低ICU的入住率及住院时间,提高患者的生存率及生存质量.     

肺复张联合个体化PEEP策略对腹腔镜手术老年患者术后肺不张程度的影响

目的评价肺复张联合个体化呼气末正压(PEEP)策略对腹腔镜手术老年患者术后肺不张程度的影响。方法择期拟行腹腔镜手术老年患者143例, 性别不限, 年龄≥65岁, BMI 18.5～30.0 kg/m2。采用随机数字表法分为肺复张联合个体化PEEP策略组(Ⅱ组)和固定PEEP组(Ⅰ组)。手术开始后Ⅰ组维持PEEP 6 cmH2O直至手术结束;Ⅱ组在麻醉诱导后进行个体化PEEP滴定。主要结局指标:气管拔管后15 min时肺部12分区超声评分, 次要结局指标:术后7 d内术后肺部并发症发生率、术后第3天时15项恢复质量量表评分、非计划入住ICU率、住院时间、术中低氧血症发生率、血管活性药物使用率及术后低血压发生率。结果与Ⅰ组比较, Ⅱ组肺超声评分、驱动压和术后肺部并发症发生率降低, 肺动态顺应性增加(P<0.05或0.01), 其他指标差异无统计学意义(P>0.05)。结论肺复张联合个体化PEEP策略可降低腹腔镜手术老年患者术后肺不张的程度。     

肺牵张指数指导不同原因急性呼吸窘迫综合征复张后呼气末正压选择的实验研究

目的研究以肺牵张指数指导不同原因急性呼吸窘迫综合征(ARDS)肺复张后呼气末正压(PEEP)的选择。方法通过静脉注射油酸、生理盐水肺灌洗和盐酸吸入建立三种犬ARDS模型。容量控制通气,回归法计算肺牵张指数(b)。调整PEEP使b=1,肺复张后再次调整PEEP,分别使b=1、<1与>1。稳定通气30 min后测定肺复张容积,同时观察呼吸力学和肺气体交换。结果盐水灌洗组复张后b=1时的PEEP为(12．8±1．8)cm H2O,显著高于盐酸吸入组[(9．2±1．8)cm H2O,P<0．05],但与油酸组比较无显著差异。与复张前b=1相比,三组复张后b=1时的氧合指数均显著升高。复张后b=1时,油酸组氧合指数为(399±61)mm Hg,较b<1[(307±71)mm Hg]时显著增加(P<0．05),与b>1时比较无显著差异。复张后b=1时,盐水灌洗组氧合指数显著高于盐酸吸入组(P<0．05),但与油酸组比较无显著差异(P>0．05)。三组动物复张后b=1时肺复张容积无明显差异,但均显著高于复张前b=1时的复张容积(P<0．05)。与复张后b>1比较,三组动物复张后b=1时均具有较高的肺顺应性和明显较低的气道平台压。结论肺牵张指数可指导不同原因ARDS复张后的PEEP选择。     

急性主动脉夹层术后低氧血症肥胖患者的逐步肺复张治疗

目的评价逐步肺复张术改善肥胖急性A型主动脉夹层术后低氧血症患者的临床疗效。方法将行深低温停循环A型急性主动脉夹层术后出现低氧血症的66例肥胖患者随机分为两组各33例。观察组行肺复张治疗,采用压力控制模式,逐步增加压力支持和呼气末正压再逐步下调;对照组行常规肺复张治疗。比较两组患者干预前后的呼吸指标(氧分压、二氧化碳分压、氧合指数、SpO_2)、循环指标的变化和呼吸机使用时间、ICU滞留时间。结果观察组肺复张30min后氧分压、氧合指数、SpO_2显著高于对照组(P0.05,P0.01);且肺复张期间两组患者血流动力学平稳;观察组呼吸机使用时间和ICU滞留时间显著短于对照组(均P0.05)。结论肺复张治疗可有效改善肥胖急性A型主动脉夹层术后低氧血症患者的氧合状态,采用逐渐递增后逐渐递减压力支持和呼气末正压的方案能维持患者的血流动力学平稳。     

个体化设置呼气末正压的临床应用进展北大核心CSCD

腹腔镜手术利用人工气腹或改变体位以使内脏远离手术区,提供开阔视野。建立人工气腹会增加腹腔压力,使膈肌上移,导致气道压力升高,较高水平气道压力牵拉以及肺泡过度扩张均会刺激肺泡上皮细胞,诱发黏附分子与炎性免疫介质因子大量释放,引起呼吸机相关肺损伤[1],而Trendelenburg等特殊体位使肺容积进一步减少,这些情况均可致肺顺应性降低,肺底部萎陷甚至不张[2],从而造成低氧血症和高碳酸血症。为了开放闭合的小气道,维持氧合,麻醉医师在机械通气时通常会设置一定水平的呼气末正压(positive end expiratory pressure,PEEP)。目前关于PEEP的有效性仍存争议,若PEEP水平过高,虽能最大限度维持肺泡开放,改善肺泡通气[3],但可能出现肺泡过度膨胀,肺阻力增加,尤其在容量不足或右室功能不全且没有进行肺复张的患者中,可能导致血流动力学波动[4];而低水平PEEP可能使小气道反复开放和关闭,不足以维持终末肺单位开放。本文就个体化设置PEEP的临床研究进展进行综述,为在微创手术中提供更好的肺保护提供参考。     

个体化PEEP通气对心脏瓣膜置换术患者术后肺部并发症的影响

目的探讨个体化呼气末正压(PEEP)通气对心脏瓣膜置换术患者术后肺部并发症的影响。方法选取2020年7月至10月择期行胸骨正中切开下心脏瓣膜置换术(单瓣/双瓣)患者64例, 性别不限, 年龄40～70岁, ASA分级Ⅱ或Ⅲ级, 心功能分级Ⅱ或Ⅲ级, BMI18～26 kg/m2。采用随机数字表法将患者分为2组(n=32):对照组(C组)与个体化PEEP组(P组)。充分肺复张后, C组设置PEEP为4 cmH2O;P组采用阶梯PEEP法进行PEEP滴定。2组患者入ICU后设置PEEP 4 cmH2O。于麻醉诱导前(T0)、肺复张前(T1)、PEEP通气20 min(T2)、术后2 h(T3)及术后24 h(T4)时抽取动脉血样, 测定血清IL-6及TNF-α浓度, T1～T4时记录血流动力学指标(HR、MAP、CVP)。根据术后住院期间患者的临床表现、影像学、血气分析诊断肺部并发症。记录术后住院时间、气管拔管时间及ICU滞留时间。结果 P组PEEP[(6.1±1.4) cmH2O]高于C组(P<0.05)。与C组比较, P组T3时血清IL-6和TNF-α浓度降低, T2时CVP升高...     

Comparison between conventional and protective one-lung ventilation for ventilator-assisted thoracic surgery

Recent papers suggest protective ventilation (PV) as a primary ventilation strategy during one-lung ventilation (OLV) to reduce postoperative pulmonary morbidity. However, data regarding the advantage of the PV strategy in patients with normal preoperative pulmonary function are inconsistent, especially in the case of minimally invasive thoracic surgery. Therefore we compared conventional OLV (VT 10 ml/kg, FiO2 1.0, zero PEEP) to protective OLV (VT 6 ml/kg, FiO2 0.5, PEEP 5 cmH2O) in patients with normal preoperative pulmonary function tests undergoing video-assisted thoracic surgery. Oxygenation, respiratory mechanics, plasma interleukin-6 and malondialdehyde levels were measured at baseline, 15 and 60 minutes after OLV and 15 minutes after restoration of two-lung ventilation. PaO2 and PaO2/FiO2 were higher in conventional OLV than in protective OLV (P<0.001). Interleukin-6 and malondialdehyde increased over time in both groups (P<0.05); however, the magnitudes of increase were not different between the groups. Postoperatively there were no differences in the number of patients with PaO2/FiO2<300 mmHg or abnormalities on chest radiography. Protective ventilation did not provide advantages over conventional ventilation for video-assisted thoracic surgery in this group of patients with normal lung function.     

双相正压通气与持续正压通气对急性呼吸窘迫综合征患者肺复张效果的比较

目的 比较双相正压通气(BIPAP)与持续正压通气(CPAP)对急性呼吸窘迫综合征(ARDS)患者肺复张的效果.方法 选择ARDS患者44例,ASA Ⅲ或Ⅳ级,性别不限,年龄35～63岁,体重52～74 kg,肺复张前基础通气模式为同步间歇指令通气联合压力支持通气,随机分为2组(n=22):CPAP组和BIPAP组.CPAP组10 s内逐渐上升呼气末正压(PEEP)至30 cm H2O,持续30 s,然后在5～10 8内恢复肺复张前通气模式.BIPAP组高水平和低水平压力分别为40、20 cm H2O,持续90 s,然后在5～10 s内恢复肺复张前通气模式.记录肺复张通气前即刻(T1),肺复张通气结束后即刻(T2)、2 min(T3)、5 min(T4)、15 min(T5)、30 min(T6)时HR、MAP、CVP、SpO2和肺动态顺应性(Cdyn).分别于T1、T5、肺复张通气结束后1 h(T7)、2 h(T8)、4 h(T9)时采集桡动脉血样,测定pH值、PaO2和PaCO2,计算PaO2/FiO2比值.结果 与CPAP组比较,BIPAP组SpO2、Cdyn、PaO2和PaO2/FiO2升高,CVP降低(P<0.05),HR和MAP比较差异无统计学意义(P>0.05).与T1时比较,CPAP组T3时MAP升高,T2时CVP升高,Cdyn降低,T3～6时SpO2和Cdyn升高,T7,8时PaO2升高,T5,7,8时PaO2/FiO2升高,BIPAP组T2～6时SpO2升高,T3～6时Cdyn升高,T5,7,8时PaO2和PaO2/FiO2升高(P<0.05).结论 与CPAP比较,BIPAP对ARDS患者行肺复张通气时血液动力学影响小,可进一步提高氧合和肺顺应性,是一种安全有效的肺复张方法 .     

Combined effects of prone positioning and airway pressure release ventilation on gas exchange in patients with acute lung injury

BACKGROUND: Prone positioning has been shown to improve oxygenation in 60-70% of patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Another way to improve matching of ventilation to perfusion is the use of partial ventilatory support. Preserving spontaneous breathing during mechanical ventilation has been shown to improve oxygenation in comparison with controlled mechanical ventilation. However, no randomized studies are available exploring the effects of preserved spontaneous breathing on gas exchange in combination with prone positioning. Our aim was to determine whether the response of oxygenation to the prone position differs between pressure-controlled synchronized intermittent mandatory ventilation with pressure support (SIMV-PC/PS) and airway pressure release ventilation with unsupported spontaneous breathing (APRV). METHODS: We undertook a prospective randomized intervention study in a medical-surgical adult intensive care unit of a university hospital. Of 45, 33 ALI patients (acute lung injury) within 72 h after initiation of mechanical ventilation, and in whom the prone position was applied according to a predefined strategy, were included in the study. After initial stabilization the patients were randomized to receive either SIMV-PC/PS or APRV with predefined general ventilatory goals (PEEP, tidal volume, inspiratory pressure and PaCO2-level). The protocol for prone positioning was the same for both treatment arms. Prone positioning was triggered by finding a PaO2/FiO2-ratio below 200 mmHg evaluated twice per day. The duration of each prone episode was 6 h. RESULTS: The first two episodes of prone positioning were analyzed. Gas exchange was measured before and at the end of prone positioning. Of the 45 patients enrolled, 33 were turned prone once and 28 twice. No significant differences were detected in baseline characteristics. Changes in oxygenation were analyzed in response to the first and second prone episodes 5 h and 24 h after randomization and initiation of SIMV-PC/PS or APRV respectively. Before the first prone episode the PaO2/FiO2-ratio was significantly better (P = 0.02) in the APRV-group (median; interquartile range) (162; 108-192 mmHg) than in the SIMV-PC/PS-group (123; 78-154 mmHg). The response in oxygenation to the first prone episode was similar in both groups: PaO2/FiO2-ratio increased 39.5; 17.75-77.5 mmHg in the SIMV-PC/PS-group and 75.0; 9.0-125.0 mmHg in the APRV-group (P = 0.49). Before the second prone episode, the PaO2/FiO2-ratio was comparable (SIMV-PC/PS 130.5; 61.0-161.0 mmHg vs. APRV 134; 98.3-175.0 mmHg). Improvement in oxygenation was significantly (P = 0.02) greater in the APRV group (82; 37.0-141.0 mmHg) than in the SIMV-PC/PS group (50; 24.0-68.8 mmHg) during the second prone episode. General ventilatory and hemodynamic variables and use of sedatives were similar in both groups during the study. CONCLUSIONS: APRV during prone positioning is feasible in the treatment of ALI patients. APRV after 24 h appears to enhance improvement in oxygenation in response to prone positioning.     

血管外肺水指数与氧合指数评估急性肺损伤程度准确性的比较

目的 比较血管外肺水指数(EVLWI)与氧合指数(PaO2/FiO2)评估急性肺损伤(ALI)程度的准确性.方法 创伤后(创伤时间＜48 h)ALI行机械通气患者16例,性别不限,年龄18～80岁,采用PiCCO监测仪监测EVLWI,建立PiCCO监测后每隔24 h采集动脉血样,测定PaO2,计算PaO2/FiO2;同时记录EVLWI,并进行肺损伤评分(LIS).分别在建立HCCO监测后24、48、72 h时按PaO2/FiO2将患者分为PaO2/FiO2≤300组(200 mm Hg＜PaO2/FiO2≤300 mm Hg)和PaO2/FiO2≤200组(PaO2/FiO2≤200 mm Hg),按EVLWI将患者分为EVLWI＜10组(EVLWI＜10 ml/kg)和EVLWI≥10组(EVLWI≥10 ml/kg).结果 与PaO2/FiO2≤300组比较,PaO2/FiO2≤200组建立PiCCO监测后24、48 h时LIS评分差异无统计学意义(P＞0.05),建立PiCCO监测后72 h时LIS评分升高(P＜0.01).与EVLWI＜10组比较,EVLWI≥10组各时点LIS评分均升高(P＜0.05或0.01).结论 临床中PaO2/FiO2作为评估ALI程度的指标存在局限性,而EVLWI在评估ALI程度方面可能比PaO2/FiO2更准确.

Abstract：

Objective To compare extravascular lung water index (EVLWI) and oxygenation index (PaO2/FiO2) in estimation of acute lung injury(ALI) .Methods Sixteen patients with post traumatic ALI (within 48 h) of both sexes, aged 18-80 yr, were studied. The patients were mechanically ventilated. Right internal jugular vein and femoral artery were catheterized and connected to PiCCO monitor (IntelliVue MP50, Philips, Netherlands).EVLWI was monitored with the PiCCO system. PaO2 was determined every 24 h. ALI was diagnosed based on the following criteria:(1)PaO2/FiO2≤300 mm Hg; (2)X-ray chest film-patchy shadows in the bilateral lungs and (3) CVP≤12 mm Hg.Lung injury score(LIS) was recorded. The patients were divided into PaO2/FiO2≤ 300 group and ≤200 group and EVLWI ≥ 10 group and ＜ 10 group. Results There was no significant difference in LIS between PaO2/FiO2 ≤300 group and PaO2/FiO2 ≤200 group at 24 and 48 h of PiCCO monitoring. At 72 h of PiCCO monitoring LIS was significantly increased in PaO2/FiO2 ≤200 group as compared with PaO2/FiO2 ≤300 group, LIS was significantly higher in EVLWI≥ 10 group than in EVLWI ＜ 10 group at 24, 48 and 72 h of PiCCO monitoring. Conclusion EVLWI is more accurate than PaO2 /FiO2 in estimation of severity of ALI.     

Effects of lung recruitment maneuver and positive end-expiratory pressure on lung volume,respiratory mechanics and alveolar gas mixing in patients ventilated after cardiac surgery

BACKGROUND: It is unclear whether positive end-expiratory pressure (PEEP) is needed to maintain the improved oxygenation and lung volume achieved after a lung recruitment maneuver in patients ventilated after cardiac surgery performed in the cardiopulmonary bypass (CPB). METHODS: A prospective, randomized, controlled study in a university hospital intensive care unit. Sixteen patients who had undergone cardiac surgery in CPB were studied during the recovery phase while still being mechanically ventilated with an inspired fraction of oxygen (FiO2) 1.0. Eight patients were randomized to lung recruitment (two 20-s inflations to 45 cmH2O), after which PEEP was set and kept for 2.5 h at 1 cmH2O above the pressure at the lower inflexion point (14+/-3 cmH2O, mean +/-SD) obtained from a static pressure-volume (PV) curve (PEEP group). The remaining eight patients were randomized to a recruitment maneuver only (ZEEP group). End-expiratory lung volume (EELV), series dead space, ventilation homogeneity, hemodynamics and PaO2 (oxygenation) were measured every 30 min during a 3-h period. PV curves were obtained at baseline, after 2.5 h, and in the PEEP group at 3 h. RESULTS: In the ZEEP group all measures were unchanged. In the PEEP group the EELV increased with 1220+/-254 ml (P<0.001) and PaO2 with 16+/-16 kPa (P<0.05) after lung recruitment. When PEEP was discontinued EELV decreased but PaO2 was maintained. The PV curve at 2.5 h coincided with the curve obtained at 3 h, and both curves were both steeper than and located above the baseline curve. CONCLUSIONS: Positive end-expiratory pressure is required after a lung recruitment maneuver in patients ventilated with high FiO2 after cardiac surgery to maintain lung volumes and the improved oxygenation.     

Mechanical ventilation during thoracic anesthesia]

Aim of the study was to test individual mechanical and functional responses to open chest lateral decubitus during one lung ventilation. We measured dependent lung pressure volume (P-V) curves of 19 patients during supine and lateral decubitus. We found that patients characterized by high FEV1 developed greater changes in P-V curve shape than those characterized by low FEV1. Based on these results we decided to test a ventilation strategy characterized by the use of ZEEP or PEEP = 10 cm H2O applied to the dependent lung. In a preliminary set of patients stratified by FEV1 we found that PEEP deteriorated PaO2/FiO2 in patients with low FEV1, while there was a trend towards improvement in patients with high FEV1. It is possible that dependent lung PEEP counteracts atelectasias in normal lungs, while it may divert blood flow or create dead space in patients with sick and stiff lungs. We conclude that during one lung ventilation in open chest lateral decubitus, ventilatory setting need to be individually tailored.     

Pressure control inverse ratio ventilation in the treatment of adult respiratory distress syndrome in patients with blunt chest trauma.

The objective of this study was to evaluate the efficacy of pressure control inverse ratio ventilation (PCIRV) in improving oxygenation in trauma patients with adult respiratory distress syndrome (ARDS) and to assess the potential risks associated with this form of treatment. This was a cohort study assessing the trends in hemodynamic and ventilatory parameters after the initiation of PCIRV, conducted at a community Level I trauma center intensive care unit. The study comprised 15 trauma patients developing severe, progressive ARDS [two or more of the following criteria: positive end-expiratory pressure (PEEP) >10 cm H2O; arterial partial pressure of oxygen divided by fraction of inspired oxygen (PaO2:FiO2) ratio <150; and peak inspiratory pressure (PIP) >45 cm H2O]: ten due to blunt chest injuries, three due to sepsis, and two due to fat emboli syndrome. PCIRV was initiated. Main outcome measures were PIP, PEEP (total, auto), oxygen saturation, cardiac index, oxygen delivery, PaO2:FiO2 ratio, compliance, evidence of complications of PCIRV, and mortality. Within 24 hours of conversion to PCIRV, the patients stabilized and the mean PaO2:FiO2 ratio rose from 96.3+/-57.8 to 146.8+/-91.1 (P<0.05) and PIP fell from 47.9+/-13.8 to 38.8+/-8.4 cm H2O; auto-PEEP increased from 0.5+/-1.9 to 7.5+/-5.6 cm H2O (P<0.05); oxygen delivery index remained stable (563+/-152 to 497+/-175 mL/min/m2); three patients developed evidence of barotrauma, one patient developed critical illness polyneuropathy, and two patients died (13%). PCIRV is an effective salvage mode of ventilation in patients with severe ARDS, but it is not without complications. Auto-PEEP levels and cardiac index should be monitored to ensure tissue oxygen delivery is maintained.     

原位肝移植术后急性肺损伤的研究进展

急性肺损伤(acute lung injury,ALI)是原位肝移植术(orthotopic liver transplant,OLT)后常见的并发症,是术后医院时间延长及死亡率增加的重要原因.ALI的诊断标准是氧合指数(分氧压/吸氧浓度)<300,肺小动脉楔压<18 mm Hg,X先示肺部浸润征.ALI可发展成为急性呼吸窘迫综合征(acute respiratory distress syndrome,ARPS),其诊断除氧合指数<200外,其他与ALI相同,此文对OLT术后ALI的发生,临床因素及机制作一综述.     

Influence of preservation solution on early lung function (Euro-Collins vs Perfadex)

BACKGROUND: This clinical study was performed to evaluate the efficiency of 2 different preservation solutions (Euro-Collins [EC] vs Perfadex [P]) on organ function in human lung transplantation. METHODS: The donor lungs for 46 patients were flushed either with EC solution (25 cases, EC group) or Perfadex (21 cases, P group). Transplant function was assayed using PaO2/FiO2 ratio after transplantation upon intensive care unit (ICU) arrival and at 12 and 24 hours later (T1, T2, and T3, respectively). We also compared the duration of mechanical ventilatory support and ICU stay. RESULTS: The PO2/FiO2 ratio was significantly better in the P than EC group at T1, T2, and T3. The duration of mechanical ventilatory support and ICU stay were lower also in P group, whereas age, sex, aetiology of lung disease, donor, PaO2/FiO2 ratio, and ischemia time did not show differences between the 2 groups. CONCLUSIONS: Our data on graft function tend to confirm better graft preservation using the P preservation solution.