肺保护性通气在开胸手术后急性呼吸窘迫综合征患者中的应用

目的 观察肺保护性通气(LPSV)对开胸手术后发生急性呼吸窘迫综合征(ARDS)患者的治疗效果.方法 37例术前无其他合并症、手术顺利而术后发生ARDS的患者在常规治疗的基础上给予机械通气[同步间歇性指令呼吸(SIMV)+压力支持模式(PSV)+呼气末正压(PEEP)或双水平气道压通气(BiPAP)],并根据通气模式的不同分为常规通气组(CMV组,20例)和肺保护性通气组(LPSV组,17例),记录两组患者机械通气后24h的动脉血气分析结果、氧合指数(PaO2/FiO2)、气道平台压(Pplat)、吸入峰值压(PIP)、PEEP及机械通气时间、气压伤等指标的差异.结果 LPSV组机械通气时间、气压伤发生率和病死率分别为7.3d、5.9%和29.4%,而CMV组为17.6d、15.0%和60.0%,两组比较差异有统计学意义 (P＜0.05);LPSV组的气道压,包括PIP和Pplat显著低于CMV组,差异有统计学意义 (P＝0.031,0.031).两组患者的动脉血氧饱和度(SaO2)、pH、动脉血二氧化碳分压(PaCO2)和PaO2/FiO2差异无统计学意义(P＞0.05).结论 LPSV可明显减少呼吸机相关性肺损伤,降低了病死率,是开胸手术后ARDS患者的一种有效通气方法.     

俯卧位通气下急性呼吸窘迫综合征患者氧合的变化

目的探讨俯卧位通气下急性呼吸窘迫综合征(ARDS)患者氧合的变化及其机制。方法23例早期ARDS患者(病程<72 h),在镇静、肌松下持续俯卧位通气2 h。呼吸机参数设定为潮气量6-8 ml/kg,吸气时间1.0-1.2 s,吸气流速40 L/min,呼吸频率12-20次/min。吸入氧浓度0.4- 1.0,呼气末正压6-18 cm H2O。观察俯卧位前即刻、俯卧位0.5、2 h及恢复仰卧位2 h的氧合指数(PaO2/FiO2)、呼吸系统静态顺应性(Cst)、心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、平均肺动脉压(MPAP)。肺动脉楔压(PAWP)、心脏指数(CI)、气道峰压(PIP)及气道阻力(Paw)。俯卧位后PaO2/FiO2比俯卧位前上升超过20%作为氧合改善的判断标准。结果与俯卧位前比较,87%患者俯卧位0.5、2 h、恢复仰卧位2 h时PaO2/FiO2和PaO2升高(P<0.01);Cst HR、MAP、CVP、MPAP、PAWP、CI、Raw、PaCO2、PIP差异无统计学意义;87%氧合改善的患者在俯卧位0.5、2 h时Cst差异无统计学意义, 恢复仰卧位2 h时Cst升高(P<0.05)。结论俯卧位通气可改善早期ARDS患者的氧合,且恢复仰卧位后氧合改善持续存在。     

高渗氯化钠对单肺通气时呼吸力学的影响

目的 探讨高渗氯化钠对单肺通气患者呼吸力学参数的影响.方法 选择拟单肺通气剖胸手术患者60例,随机均分为高渗氯化钠治疗组(H组)和对照组(C组).在单肺通气30 min后经中心静脉导管输注7.5％氯化钠溶液(H组)或生理盐水(C组)2 ml/kg.观察单肺通气前(T1)、单肺通气后30 min(T2)、输注后30 min(T3)、60 min(T4)、单肺通气结束时(T5)的动态肺顺应性(Cdyn)、气道峰压(Ppeak)、气道平均压(Pmean)、动脉血氧分压(PaO2)、血清Na+浓度.结果 与T1时比较,两组患者T2时的Cdyn、PaO2明显降低,Ppeak、Pmean明显升高(P＜0.05).与T2时比较,T3～Ts时H组Cdyn、PaO2逐渐升高,Ppeak、Pmean逐渐下降(P＜0.05),且Cdyn、PaO2明显高于C组,Ppeak明显低于C组(P＜0.05).T4、T5时H组Pmean明显低于C组(P＜0.05).结论 7.5％氯化钠溶液对单肺通气患者的各呼吸力学参数有改善作用,对肺通气功能具有保护作用.     

肺泡表面活性物质肺灌洗治疗急性呼吸窘迫综合征

目的研究肺泡表面活性物质肺灌洗治疗急性呼吸窘迫综合征（ARDS）的效果。方法用12ml／kg 0．0225N的盐酸经气管注入新西兰白兔肺内,纯氧机械通气1h后,将符合PaO2／FiO2≤150mmHg的动物随机分成五组,每组5只。分别用生理盐水（Ⅰ组）、浓度为1g／L（Ⅱ组）、3g／L（Ⅲ组）、6g／L（Ⅳ组）、12g／L（Ⅴ组）的肺泡表面活性物质肺灌洗,灌洗容量为10ml／kg,观察每组治疗后的PaO2／FiO2的变化情况,并对肺标本行病理切片检查。结果Ⅰ组、Ⅱ组治疗后PaO2／FiO2没有改善,而Ⅲ组、Ⅳ组、Ⅴ组肺灌洗后PaO2／FiO2均显著改善,但这种效果随时间推移逐渐消失,病理切片显示Ⅲ组、Ⅳ组、Ⅴ组中肺泡间质充血水肿和肺泡腔渗出均较Ⅰ组、Ⅱ组明显减轻。结论采用浓度为3g／L以上的外源性肺泡表面活性物质对盐酸诱导的ARDS行肺灌洗有明显疗效,但效果不能持久。     

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.     

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 .     

重症急性胰腺炎并发ALI/ARDS24例临床分析

目的：探讨重症急性胰腺炎并发急性肺损伤（ALI）／急性呼吸窘迫综合征（APDS）的证断与治疗。方法：回顾性分析本院1997年1月至2000年12月收治的28例重症急性胰腺炎中并发的24例ALI／ARDS患者。结果：重症急性胰腺并发ALI／ARDS的发病率高达85．7％,20例为ALI,4例为ARDS,均治愈。结论：在重症急性胰腺炎的急性反应期,应反复测定血气分析,不应拘泥于动脉氧分压数值,当氧合指数（PaO2/FiO2）≤300mmHg,可早期证断出ALI,经积极处理,可避免向ARDS转化。     

ALI/ARDS病人侧卧位通气的疗效观察

目的探讨急性肺损伤 /急性呼吸窘迫综合征 (ALI/ARDS)病人实施侧卧位通气的效果。方法对 18例ALI/ARDS病人实施侧卧位通气 ,分别于通气前、侧卧位通气 1h后及恢复仰卧位通气 1h做血气分析 ,观察变动体位通气对呼吸循环指标的影响。结果 12例侧卧位通气有效 ,有效率 6 6 .7% ;其氧分压 (PaO2 )、氧分压 /吸氧浓度 (PaO2 /FiO2 )明显高于通气前 (均P <0 .0 1) ;恢复仰卧位 1h后上述指标有所下降 ,但仍高于通气前 (P <0 .0 5 ) ;体位变动通气时病人呼吸循环指标变化比较 ,差异无显著性意义 (均P >0 .0 5 )。结论侧卧位通气对ALI/ARDS特别是对ALI病人治疗有效 ,与俯卧位通气比较 ,实施更方便、安全。     

重症急性胰腺炎合并急性呼吸窘迫综合征16例临床分析

目的 探讨重症急性胰腺炎(severe acute pancreatitis,SAP)合并急性呼吸窘迫综合征(acute respiratory distress syndrome.ARDS)的临床特点和治疗方法.方法 回顾总结分析我院收治的16例SAP合并ARDS患者临床资料.结果 13例SAP合并ARDS患者治疗有效;3例2周内因治疗无效死亡,死因为多器官功能衰竭、严重感染、休克.治疗有效患者机械通气时间为3～10 d(平均6.5 d).13例治疗有效患者确诊ARDS即刻和机械通气12 h的pH、氧合指教(PaO2/FiO2)、PaCO2、PaO2等相比较,氧合指数、PaCO2、PaO2差异有统计学意义.治疗有效患者肺损伤评分明显下降(P＜0.05).结论 胰腺炎症的控制是治疗的关键.早期诊断ARDS,予以机械通气和激素等对症治疗能提高疗效.     

右美托咪定对老年患者单肺通气期间氧合和呼吸力学的影响

目的观察右美托咪定对老年患者单肺通气期间氧合和呼吸力学的影响。方法择期行胸腔镜下肺叶切除术的老年患者60例,男32例,女28例,年龄65~77岁,BMI 20.3~27.9kg/m2,ASAⅡ或Ⅲ级。随机分为两组:右美托咪定组(D组)和生理盐水组(C组),每组30例。D组在单肺通气后10min内输注右美托咪定1.0μg/kg,然后以0.5μg·kg-1·h-1速率输注至单肺通气结束,C组输注等容量生理盐水。在单肺通气前1min(T0)、单肺通气后30min(T1)和单肺通气后60min(T2)各时点抽取桡动脉血2ml行血气分析,计算PaO2/FiO2。在T1和T2时进行呼吸力学监测,监测参数包括肺动态顺应性(Cdyn)、气道峰压(Ppeak)、气道平均压(Pmean)和无效腔气量与潮气量之比(VD/VT)。记录ICU停留时间和术后72h内的肺不张、肺炎、急性肺损伤等并发症情况。结果与T0时比较,T1和T2时两组PaO2/FiO2明显降低(P0.05)。与C组比较,T1和T2时D组PaO2/FiO2和Cdyn明显升高(P0.05),Ppeak、Pmean和VD/VT明显降低(P0.05),ICU停留时间明显缩短(P0.05),术后肺不张明显减少(P0.05)。两组肺炎和急性肺损伤差异无统计学意义。结论老年患者单肺通气期间输注右美托咪定可以改善血液氧合和呼吸力学,不增加急性肺损伤的发生,可减少术后肺不张,缩短ICU停留时间。     

Tracheostomy in a patient with severe acute respiratory syndrome

The coronavirus which causes severe acute respiratory syndrome(SARS) is a virulent and highly contagious organism. Of the1755 SARS patients in Hong Kong, over 400 were healthcare workers.Meticulous attention to infection control and teamwork are essentialto minimize cross-contamination and prevent staff from contractingthe illness. These points are especially pertinent when anaesthetizingSARS patients for high-risk procedures such as tracheostomy.We describe the management of such a case. Br J Anaesth 2004; 92: 280–2     

Protective ventilation of patients with acute respiratory distress syndrome

The majority of patients with acute respiratory distress syndrome(ARDS) require mechanical ventilation. This support providestime for the lungs to heal, but the adverse effects of mechanicalventilation significantly influence patient outcome. Traditionally,these were ascribed to mechanical effects, such as haemodynamiccompromise from decreased venous return or gross air leaks inducedby large transpulmonary pressures. More recently, however, theARDS Network study has established the clinical importance oflowering the tidal volume to limit overdistension of the lungwhen ventilating patients with ARDS. This study suggests thatventilator-associated lung injury (VALI) caused by overdistensionof the lung contributes to the mortality of patients with ARDS.Moreover, the results from clinical and basic research haverevealed more subtle types of VALI, including upregulation ofthe inflammatory response in the injured and overdistended lung.This not only damages the lung, but the overflow of inflammatorymediators into the systemic circulation may explain why mostpatients who die with ARDS succumb to multi-organ failure ratherthan respiratory failure. The results of these studies, thepresent understanding of the pathophysiology of VALI, and protectiveventilatory strategies are reviewed. Br J Anaesth 2004; 92: 261–70     

Prone positioning ventilation for treatment of acute lung injury and acute respiratory distress syndrome

Patients who are diagnosed with acute lung injury/acute respiratory distress syndrome (ALI/ARDS) usually have ventilation-perfusion mismatch, severe decrease in lung capacity, and gas exchange abnormalities. Health care work-ers have implemented various strategies in an attempt to compensate for these pathological alterations. By rotating patients with ALI/ARDS between the supine and prone position, it is possible to achieve a significant improvement in PaO2/FiO2, decrease shunting and therefore improve oxy-genation without use of expensive, invasive and experimen-tal procedures.     

Aerosolized surfactant therapy for endotoxin-induced experimental acute respiratory distress syndrome in rats

We have compared the effects of inhalation of aerosolized surfactanton experimental acute respiratory distress syndrome. Escherichiacoli endotoxin (55 (SD 20) mg kg^–1) was injected intothe tracheas of 36 adult rats anaesthetized and mechanicallyventilated with pure oxygen. When the Pa_O2 decreased to 11.3(3.3) kPa, the animals were randomly subjected to inhalationof aerosolized modified natural surfactant (MNS) for 0 min (controlgroup), 30, 60, and 120 min. In the control group, Pa_O2 remainedbelow 12 kPa for 180 min. In the groups receiving inhalationof surfactant for 30 and 60 min, Pa_O2 increased but decreasedsoon after termination of the inhalation. In contrast, Pa_O2of the group receiving inhalation of surfactant for 120 mincontinued to increase, reaching 52.1 (12.5) kPa at 180 min (P<0.05vs control). Thus, we conclude that improvement in gas exchangeas a result of inhalation of MNS depends on the duration ofinhalation. Br J Anaesth 2001; 87: 266–71     

Retrospective analysis on acute respiratory distress yndrome in ICU

OBJECTIVE: To assess the incidence, etiology, physiological and clinical features, mortality, and predictors of acute respiratory distress syndrome (ARDS) in intensive care unit (ICU). METHODS: A retrospective analysis of 5 314 patients admitted to the ICU of our hospital from April 1994 to December 2003 was performed in this study. The ARDS patients were identified with the criteria of the American-European Consensus Conference (AECC). Acute physiology and chronic health evaluation III (APACHE III), multiple organ dysfunction syndrome score (MODS score), and lung injury score (LIS) were determined on the onset day of ARDS for all the patients. Other recorded variables included age, sex, biochemical indicators, blood gas analysis, length of stay in ICU, length of ventilation, presence or absence of tracheostomy, ventilation variables, elective operation or emergency operation. RESULTS: Totally, 131 patients (2.5%) developed ARDS, among whom, 12 patients were excluded from this study because they died within 24 hours and other 4 patients were also excluded for their incomplete information. Therefore, there were only 115 cases (62 males and 53 females, aged 22-75 years, 58 years on average) left, accounting for 2.2% of the total admitted patients. Their average ICU stay was (11.27+/-7.24) days and APACHE III score was 17.23+/-7.21. Pneumonia and sepsis were the main cause of ARDS. The non-survivors were obviously older and showed significant difference in the ICU length of stay and length of ventilation as compared with the survivors. On admission, the non-survivors had significantly higher MODS and lower BE (base excess). The hospital mortality was 55.7%. The main cause of death was multiple organ failure. Predictors of death at the onset of ARDS were advanced age, MODS > or = to 8, and LIS > or = 2.76. CONCLUSIONS: ARDS is a frequent syndrome in this cohort. Sepsis and pneumonia are the most common risk factors. The main cause of death is multiple organ failure. The mortality is high but similar to most recent series including severe comorbidities. Based on this patient population, advanced age, MODS score, and LIS may be the important prognostic indicators for ARDS.     

Microvessel damage in acute respiratory distress syndrome: the answer may not be NO

Br J Anaesth 2001; 87: 272–9     

Severe acute respiratory syndrome mimicking acute abdomen

Severe acute respiratory syndrome (SARS) is a novel epidemic disease. The clinical presentation can sometimes be very non-specific. The present study reports a case of SARS, which presented as acute abdomen, warranting laparotomy. The atypical presentation in the present case reminded us of the importance of strict infection control measures in all surgery-related specialist workplaces.     

Potential therapeutic application of adult stem cells in acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) remains a poor prognosis in spite of the recent development of new therapeutic strategies. Cell-based therapy with stem cells has been considered as a promising way for the treatment of vital organ damage. Putative endogenous stem cells have been shown to be located within the adult lung in the basal layer of the upper airways, within or near pulmonary neu-roendocrine cell rests, at the bronchoalveolar junction, as well as within the alveolar epithelium. These stem cells are hypothesized to be the source of lung regeneration and repair. But this mechanism seems to be insufficient after lung injury. There is increasing excitement over the last few years with the suggestion that exogenous stem cells may offer new treatment options for ARDS. Exogenous stem cells have the abihty to differentiate and function as both airway and lung parenchymal epithelial cells in both in vitro and in-creasingly in vivo experiments. However, there is great con-troversy concerning the repair effect of adult stem cells in lung injury. This review evaluates the advances in endog-enous respiratory stem cells, and assesses the evidence for the use of stem cells in the repair of lung injury.     

体外膜肺联合血液滤过治疗肺肾衰竭的实验研究

目的 观察体外膜氧合器（ECMO）联合高容量血液滤过（HVHF）对急性呼吸窘迫综合征（ARDS）、急性肾功能衰竭（ARF）的治疗作用。 方法 采用实验犬32只，随机分为A、B、C、D 4组。静脉注射油酸复制ARDS模型及双侧输尿管结扎复制急性肾功能衰竭模型。A组用ARDS呼吸机治疗；B组ARDS用ECMO治疗；C组ARDS＋ARF用HVHF治疗；D组ARDS＋ARF用ECMO联合HVHF治疗。监测血气、血流动力学以及血生化等指标。 结果 治疗后B组氧分压（PaO2）逐步上升，在治疗4 h后高于A组[（95.58±8.14） 比（82.79±12.37） mm Hg，P < 0.05]； C组PaO2治疗中较成模时无明显改善；D组PaO2呈逐渐上升趋势，在各时间点均高于C组（P < 0.05）。各组血流动力学指标在治疗中保持稳定。C、D组HVHF治疗后Scr、BUN明显降低[C组：Scr (320.89±65.42) 比(655.04±181.22) μmol/L，BUN (20.42±6.65) 比（41.53±10.59）mmol/L；D组：Scr (334.15±45.97)比（697.48±101.66） μmol/L，BUN (19.12±6.39) 比（39.10±11.60） mmol/L，P均< 0.01]。 结论 ECMO可以有效地改善ARDS低氧血症，联合HVHF可以提供肺肾功能联合支持。