單肺通氣低氧血癥綜合防治進展

單肺通氣低氧血癥綜合防治進展病例(一)患者，男，66歲。行左肺葉切除術(shù)

插入右側(cè)雙腔導(dǎo)管,在纖支鏡下定位。右上中下肺葉對位良好。右側(cè)臥位開胸后即開始單肺通氣，30min后SpO2就開始下降,一直到87-88%。

2病例(一)

立即進行纖支鏡檢查,發(fā)現(xiàn)右上肺開口已錯位,沒有通氣.3病例(一)

經(jīng)調(diào)整后,SpO2逐漸上升98-99%.4病例(二)

男，73歲。右上葉肺癌行肺葉切除術(shù)。插入左側(cè)雙腔導(dǎo)管,在纖支鏡下定位。左上下肺葉對位良好。左側(cè)臥位開胸后即開始單肺通氣，發(fā)現(xiàn)氣道壓上升到35-40cmH20,SpO2逐漸開始下降。5病例(二)

纖支鏡檢查:導(dǎo)管過深到左下葉支氣管，左上肺通氣不良6病例(二)

經(jīng)調(diào)整后,SpO2逐漸上升98-99%.

7病例(三)

男，53歲，68公斤。因“右上葉肺癌”行右肺葉切除術(shù)。插入左側(cè)雙腔導(dǎo)管,在纖支鏡下定位。左上下肺葉對位良好。單肺通氣40min后血氧就開始下降,一直到90%以下。

纖支鏡檢查對位良好。

8立即給予非通氣側(cè)2-5cmH20CPAP,SpO2逐漸上升98-99%.9一、低氧血癥的原因

1導(dǎo)管位置不正確2單肺通氣及側(cè)臥位的影響3缺氧性肺血管收縮（HPV）

4其他因素的影響

每年廣東省晉升高級職稱考題10

一導(dǎo)管位置不正確是出現(xiàn)低氧血癥最常見的原因

11一導(dǎo)管位置不正確左側(cè)

左側(cè)過淺示意圖12一導(dǎo)管位置不正確左側(cè)

左側(cè)過淺實圖13導(dǎo)管位置不正確左側(cè)

左側(cè)過深示意圖14導(dǎo)管位置不正確左側(cè)

左側(cè)過深實圖15那么下面這種情況呢?左側(cè)插管,未看到窿突.即可能過深也可能過淺16導(dǎo)管位置不正確右側(cè)

右側(cè)過深示意圖17導(dǎo)管位置不正確右側(cè)

右側(cè)過深實圖18

插反19一、導(dǎo)管位置不正確例1患者左肺手術(shù)，插入右側(cè)雙腔氣管，右上肺對位不好，這在臨床是非常常見的情況。特別是在沒有纖維支氣管鏡定位的情況下就更容易發(fā)生。

20一、導(dǎo)管位置不正確

即使在有纖支鏡的情況下，

平臥位---側(cè)臥位后：右上肺開口錯位率可達50-70%，偶達80%以上。因此，在已有一側(cè)肺未通氣的情況下，再加上右上肺通氣不良，V/Q比更加失衡，則低氧血癥就在所難免。

21一、導(dǎo)管位置不正確

例2和例3患者右肺手術(shù)，插入的是左側(cè)雙腔氣管。在插管的處理和對位方面也比插入右側(cè)雙腔氣管要容易得多，但這同樣不能保證不產(chǎn)生低氧血癥，只是低氧血癥的發(fā)生率要低于右側(cè)插管。但如果左側(cè)插管時的位置同樣不理想的話，則和右側(cè)插管相比也沒有優(yōu)勢可言。22二、單肺通氣及側(cè)臥位的影響單肺通氣單肺通氣時，術(shù)側(cè)肺無通氣，使通氣/灌注比值下降，因此肺內(nèi)分流增加。在開始的10min左右，雖然流經(jīng)無通氣肺泡的血流，可利用肺內(nèi)剩余的氧，而在20-30min后PaO2就明顯下降.

23二、單肺通氣及側(cè)臥位的影響

側(cè)臥位下肺被壓1:縱隔和心臟2:體位墊3:上橫隔下肺順應(yīng)性低于上肺，增加閉合肺容量，如通氣不足易發(fā)生微小肺不張，功能殘氣量減少，也引起PaO2下降。24

（三）缺氧性肺血管收縮（HPV）被抑制

肺泡缺氧刺激

肽類內(nèi)皮素，血栓素A,血小板激活因子,白三烯，內(nèi)皮細胞依賴收縮因子很強的血管收縮作用形成缺氧性肺血管收縮從而使病側(cè)肺血流減少，低氧血癥有所緩解

全麻抑制HPV25四、其他因素的影響

剖胸后胸腔負壓消失手術(shù)操作刺激低血容量心律不齊及心肌抑制等因素使心排血量減少都是引起低氧血癥的原因之一。26二、低氧血癥的處理

1導(dǎo)管位置2V/Q3HPV

27

低氧血癥的處理：

（1）導(dǎo)管位置不正確的危害：

缺氧肺不張高氣道壓分泌物積蓄術(shù)后感染率增加

28最理想的方法一、常規(guī)使用纖支鏡糾正雙腔導(dǎo)管錯位首要問題是對位問題二、首選插左側(cè)雙腔導(dǎo)管（左肺2葉，右肺3葉）更加容易對位良好.

29理想的位置:Goldenstandard

側(cè)管:蘭色套囊的邊緣和窿突平齊主管:直接看到上(中)下肺葉支氣管開口Theidealpositionwasdefinedasthatinwhichthecarinawaslocatedatthesamelevelwiththemiddle5mmbetweentheproximalmarginoftheendobronchialballoonandthecircumferentialblackmark

23130低氧血癥的防治我們的觀察發(fā)現(xiàn)靠聽診方法的定位滿意的病人，再用纖支鏡定位，發(fā)現(xiàn)接近50%的導(dǎo)管不在一種理想的位置31

一、使用纖支管鏡糾正雙腔導(dǎo)管錯位

聽診:導(dǎo)管位置正確的172例病人中，經(jīng)纖支鏡發(fā)現(xiàn)46%例是導(dǎo)管錯位的，其中15%情況嚴重。再轉(zhuǎn)為側(cè)臥位后，發(fā)現(xiàn)54%例雙腔氣管導(dǎo)管錯位，其中28%情況嚴重。右側(cè)導(dǎo)管明顯比左側(cè)導(dǎo)管錯位的發(fā)生率高。Klein等32Reliabilityofauscultationinpositioningofdouble-lumenendobronchialtubes.AlliaumeBCanJAnaesth.1992Sep;39(7):687-90.

Auscultationisawell-establishedtechniquetoconfirmthepositionofdouble-lumenendobronchialtubes(DLTs).However,someauthorshaverecommendedthatfibreopticbronchoscopy(FOB)isalsoindicated.TheaimsofthisstudyweretodeterminefirstifbronchoscopyafterblindplacementofDLTsimprovedpositioning;andsecondifpreoperativebronchoscopycoulddetectdifficultintubation.Twenty-fourpatientsundergoingaorticorlungsurgerywerestudied.Afterintubationwithasingle-lumentube,aninitialFOBwasperformedbyanindependentobservertochecktheairwayanatomy.Then,thesingle-lumentubewasreplacedbyaDLTusingaclassical"blind"intubationmethod.SubsequentFOBwasperformedfirstbytheindependentobservertorecordtheDLTpositionandnextbytheinvestigatorsforimprovementorcorrectionoftheirpositioningundervisualcontrol.FibreopticbronchoscopyafterblindplacementofDLTsresultedinrepositioning78%left-sidedDLTsand83%right-sidedDLTs.PreoperativebronchoscopydidnotalwaysdetectanairwayabnormalitywhichmightleadtodifficultpositioningoftheDLTs.

Inconclusion,auscultationisanunreliablemethodofconfirmingthepositionofDLTsandshouldbefollowedbyfibreopticbronchoscopy.33

轉(zhuǎn)為側(cè)臥位后如何？

METHODS:EightypatientsundergoingelectivethoracotomythatrequiredananesthesiawiththeuseofleftDLTwerestudied.AnOlympusLF-Pbroncho-fiberscopewasusedtoestimatethedistancebetweenthecarinaandthedistalendoftheDLTviathetracheallumenbeforeandafterpatientpositioning.RESULTS:AllDLTwereconfirmedtobeinthecorrectpositionineightypatientsbeforepatientpositioning.Afterpatientpositioning,theDLTmovedproximally1.5cm,1cmand0.5cmineighteen(22.5%),sixteen(20%)andeight(10%)patientsrespectively.Inninepatients(11.25%)DLTdisplacementafterpositioningresultedinafailuretoventilatethelungsseparatelyandrequiredreadjustmentoftheDLT.CONCLUSIONS:OurresultsuggeststhatthereisahighincidenceofDLTdisplacementduringpatientpositioning.34平臥位定位很好

側(cè)臥位定位很好是不是就？35手術(shù)牽拉導(dǎo)致的導(dǎo)管移位3637肺大泡破裂導(dǎo)致的移位38

Double-lumentubepositionshouldbeconfirmedbyfiberopticbronchoscopy.

CohenE.DepartmentofAnesthesiology,MountSinaiMedicalCenter,NewYork,USA.PURPOSEOFREVIEW:ThisreviewispartofProandContrauseoffiberopticbronchoscopytoconfirmthepositionofadoublelumentube.Thepurposeofthisreviewistohighlightthecircumstanceswherefiberopticbronchoscopyshouldbeusedinconjunctionwithlungseparation,rightsideddouble-lumentubepositioning,andtoidentifyfinemalpositionforgenerallymissedbyclinicalsigns.RECENTFINDINGS:Untilseveralyearsago,confirmationofadouble-lumentube(DLT)positionwaslimitedtoinspectionandauscultation.Fiberopticbronchoscopeswereusuallyonlyavailableinthebronchoscopesuitefortheexclusiveuseofthepulmonarypersonnel.Today,inmostinstitutions,fiberopticbronchoscopesofdifferentdiametersareavailableintheoperatingroomforusebytheanesthesiapersonnel.SUMMARY:Advancesintechnologyandimprovedqualityoftheendoscopesimagemakethetechniqueeasytousewitharelativelysimplelearningcurve.Infact,fiberopticworkshops,thoracicworkshopsanddifficultairwayworkshopsareofferedinnearlyallimportantanesthesiameetings.CurrOpinAnaesthesiol.2004Feb;17(1):1-6.

39首要原則導(dǎo)管定位準確

隆突

小隆突40如果導(dǎo)管位置好而發(fā)生低氧血癥呢？41

那我得想想…..42一、非通氣側(cè)處理持續(xù)氣道正壓通氣低氧氣體高頻噴射通氣431、持續(xù)氣道正壓通氣

（ContinuousPositiveAirwayPressure）優(yōu)點：非通氣側(cè)肺血流有一定氧合:V增加血管阻力,使血流轉(zhuǎn)向下肺:Q

減少肺內(nèi)分流,提高動脈氧合44過去使用CPAP的辦法

1

非通氣側(cè)用氧管吹入氧氣2水封瓶缺點：壓力難以控制極易使術(shù)側(cè)膨漲難以常規(guī)應(yīng)用。45CPAP的改進辦法：CPAP系統(tǒng)

46

調(diào)節(jié)壓力閥到2-5cmH20

對手術(shù)操作無任何影響

使更多的靜脈血得到氧合

充入的O2使小肺泡充分開放

增加靜止肺容量

增大肺泡通氣

改善低氧血癥。

CPAP系統(tǒng)47持續(xù)氣道正壓通氣22例肺癌化療后患者分成兩組A組非通氣側(cè)肺直接開口于大氣中B組非通氣側(cè)肺給予0.2kPaCPAP結(jié)果:B組分流率低于A組,氧合高于A組

馬武華等.中山大學學報,2004,24(1)48

Acomparisonoftheeffectsof50%oxygencombinedwithCPAPtothenon-ventilatedlungvs.100%oxygenonoxygenationduringone-lungventilation

AnasthesiolIntensivmedNotfallmedSchmerzther.2004Jun;39(6):360-4.German.

方法:20個病人分成兩組。一組非通氣側(cè)給以氧100%，另一組非通氣側(cè)給以氧50%加5cmH20CPAP結(jié)果:OLV-CPAP198+/-40mmHg，Qs/Qt:30+/-6%OLV-100%181+/-38mmHg;Qs/Qt:34+/-8%;

5cmH20CPAP對手術(shù)沒有任何影響492、非通氣側(cè)肺使用高頻噴射通氣

可比使用CPAP更顯著地提高動脈氧合（HighFrequencyJetventilation,HFJV）50

方法:

25個病人隨機分成2組A組在非通氣側(cè)給予HFJVB組在非通氣側(cè)給予CPAP觀察OLV15min，和給予處理后15min,30min的血氧和肺內(nèi)分流的變化.結(jié)果:

HFJVfrom173(T2)to344(T3)and359.9(T4)CPAPfrom153(T2)to243(T3)and249.7(T4)HFJV38.7%(T2)to27.0%(T3)and25.9%(T4)CPAP44.6%(T2)to34.3%(T3)and32.6%(T4)

CONCLUSIONS:

BothHFJVandCPAPcanimproveoxygenationduringOLV.

5152

3非通氣側(cè)給予非氧氣體532非通氣側(cè)肺吸入低氧氣體

Therightlungwasventilatedcontinuouslywith100%oxygen,whiletheleftlungwasventilatedalternatelywith100%O2,anhypoxicgasmixturecontaining4%O2,3%CO2,balanceN2for4h,insixdogHypoxicventilationoftheleftlungresultedinanimmediateandsustaineddecreaseinleftlungbloodflow(QL%)from39.0+/-1.8%to9.9+/-3.6%at15minofhypoxicventilation.

結(jié)論:hypoxicventilationoftheleftlungyieldedanimmediateandsustaineddecreaseinleftlungbloodflowfor4h.

542非通氣側(cè)給予非氧氣體

氧化亞氮(N2O)減少Q(mào)55非通氣側(cè)肺吸入氧化亞氮(N2O)20例肺癌患者分成2組A組:非通氣側(cè)肺直接開口于大氣中B組:非通氣側(cè)肺給予0.2kPaN2O

B組分流率低于A組,氧合高于A組馬武華,等.中國病理生理雜志，2004，20（11）

56二、通氣側(cè)肺的處理

1呼氣末正壓通氣2吸入一氧化氮(NO)

571、呼氣末正壓

（PositiveEndExpiratoryPressure,PEEP）

優(yōu)點：

增加呼氣末肺泡的容積改善肺的功能殘氣量防止肺泡塌陷，改善VA/Q比值可以增加動脈血氧分壓。58呼氣末正壓

（PositiveEndExpiratoryPressure,PEEP）缺點：使胸內(nèi)壓升高及肺容量增大造成血流動力學紊亂SV、CO、CI均下降增加肺血管阻力，影響非通氣側(cè)肺血流向通氣側(cè)肺的再分布。59最適合單肺通氣時的PEEP60Effectsofthelungprotectiveventilatorystrategyonproinflammatorycytokinereleaseduringone-lungventilation

林文前等癌癥.2008，27(8):870-3

METHODS:Fortypatientsunderwentesophagectomywererandomlydividedintoconventionalventilation(CV)group(n=20)andprotectiveventilation(PV)group(n=20).InCVgroup,allpatientsreceivedtwo-lungventilation(TLV)andOLVwithatidalvolume(VT)of10mL/kgandaninspiration/expirationratio(I/E)of1:1.5.InPVgroup,allpatientsreceivedTLVwithaVTof10mL/kgandanI/Eratioof1:1.5,andreceivedOLVwithaVTof5-6mL/kgandanI/Eratioof1:1,alongwithpositiveend-expiratorypressure(PEEP)presetat3-5cmH2O.CONCLUSIONS:ConcentrationsofIL-6andIL-8areincreasedduringandafterOLVinthoracicsurgery.ThelungprotectiveventilatorystrategycanreducetheairwaypressureandairwayresistanceduringOLV,decreasethereleaseofIL-6andIL-8,andinhibitlunginflammatoryresponsesduringOLVandpostoperatively.61622、吸入一氧化氮(NO)及靜脈用Almitrine

NO研究表明：NO有舒張肺血管床的作用，已證明ARDS的病人吸入低濃度NO（10ppm）能有效地提高氧合機制:可能是增加肺泡通氣良好區(qū)域的血流，減少肺內(nèi)分流。Almitrine

作用于頸動脈體化學感受器,興奮呼吸,加強肺泡-毛細血管的氣體交換,提高血氧分壓.

63Theeffectsofinhalednitricoxideanditscombinationwithintravenous

almitrineonPao2duringone-lungventilationinpatientsundergoing

thoracoscopicprocedures.

AnesthAnalg.1997Nov;85(5):1130-5.

Theaimofthisstudywastoassesswhetherhypoxemiaduringone-lungventilation(OLV)canbepreventedbyinhalednitricoxide(NO)(PartI)orbyitscombinationwithintravenous(IV)almitrine(PartII)in40patients.InPartI,20patientsweredividedintotwogroups:onereceivedO2(Group1),onereceivedO2/NO(Group2).InPartII,20patientsweredividedintotwogroups:onereceivedO2(Group3),onereceivedO2/NO/almitrine(Group4).InGroups2and4,NO(20ppm)wasadministeredduringtheentireperiodofOLV,andalmitrinewascontinuouslyinfused(16microgxkg(-1)xmin[-1])inGroup4.DuringOLV,Pao2valuesdecreasedsimilarlyinGroups1and2.IMPLICATIONS:

OurstudyshowedthatinhalednitricoxidealonedidnotinfluencePa02evolution.WethentriedaddingintravenousalmitrinetonitricoxidewithamazinglygoodresultsonPa02.

64

這種作用有點類似針灸哦65Almitrine

66三、通氣側(cè)肺PEEP+非通氣側(cè)肺CPAP上肺0.98kPa的CPAP給氧下肺0.47kPa的PEEP通氣是OLV最理想的通氣方式我的建議：上肺0.5kPa下肺0.47kPaObora等67最有效的方法雙肺通氣68以下也值得我們關(guān)注1麻醉方法的選擇2通氣方式的選擇3體位的選擇4不同的氧濃度的影響5不同導(dǎo)管大小的影響6麻醉藥物的影響7血管活性藥物的影響8其他藥物的作用69一、麻醉方法的選擇

1氣管內(nèi)全麻2氣管內(nèi)全麻復(fù)合硬膜外麻醉

3硬膜外麻醉70Arterialoxygenationduringone-lungventilation:combinedversusgeneralanesthesia.GaruttiIAnesthAnalg.1999Mar;88(3):494-9.

方法:60個病人隨機分成2組.全麻組propofol/rocuronium

/

fentanyl全麻+硬外組propofol/rocuronium/bupivacaine0.5%.

結(jié)果:PaO2duringOLVin15minand30min全麻組:175mmHg182mmHg全麻+硬外:120mmHg118mmHg,Qs/Qt%更高WeconcludethatusingtheTEAregimenisassociatedwithalowerPaO2andalargerintrapulmonaryshuntduringOLVthanwithtotali.v.anesthesiaalone.

.71一、麻醉方法的選擇

原因：

阻滯了胸段交感神經(jīng)心輸出量的降低抑制HPV的發(fā)生從而肺分流增加

72ThoracicEpiduralAnesthesiaCombinedwithGeneralAnesthesia:ThePreferredAnestheticTechniqueforThoracicSurgeryVeraVonDossow,MD*,MartinWelte,MDAnesthAnalg2001;92:848-854

AnincreaseinCOisusuallyassociatedwithanincreasedshuntfractionwhilePaO2isunchangedordecreased.DecreasesinCOareassociatedwithdecreasedPAP,whichcanpotentiateHPVandreduceshunt73

Theeffectofthoracicepiduralanalgesiaontheoccurrenceoflatepostoperativehypoxemiainpatientsundergoingelectivecoronarybypasssurgery:arandomizedcontrolledtrial.

Lundstr?mLH,

lars.hyldborg@dadlnet.dkChest.2005Sep;128(3):1564-70.

方法:50個行冠脈搭橋手術(shù)的病人隨機分成2組A組:全麻B組:全麻復(fù)合硬膜外并行硬膜外布比卡因術(shù)后鎮(zhèn)痛.監(jiān)測術(shù)后第2晚和第3晚的SpO2結(jié)果:1術(shù)后第2晚低氧血癥的發(fā)生率56%(28of50patients)第3晚89%(41of46patients)2第3晚低氧血癥似乎比第2晚低氧血癥有輕度的加重3第3晚低氧血癥B組(25of25patients)和A組比(16of21patients;)發(fā)生率更高(p<0.05).4但總的兩組之間沒有統(tǒng)計學差異.結(jié)論;硬膜外麻醉和行硬膜外布比卡因術(shù)后鎮(zhèn)痛對低氧血癥的生沒有保護作用.

74Epiduralanesthesiainawakethoracicsurgery

TommasoClaudioMineo*EurJCardiothoracSurg2007;32:13-19.

硬膜外麻醉應(yīng)用逐漸增多

Inordertoreducetheadverseeffectsofgeneralanesthesia,thoracicepiduralanesthesiahasbeenrecentlyemployedtoperformawakethoracicsurgeryproceduresincluding*coronaryarterybypass冠狀動脈旁路手術(shù)*managementofpneumothorax,氣胸*resectionofpulmonarynodulesandsolitarymetastases肺結(jié)節(jié)和轉(zhuǎn)移瘤的切除*lungvolumereductionsurgery肺減容手術(shù)*transsternalthymectomy經(jīng)胸骨胸腺切除術(shù)

75Epiduralanesthesiainawakethoracicsurgery

TommasoClaudioMineo*EurJCardiothoracSurg2007;32:13-19.Cardiovasculareffectsofepiduralanesthesiainclude*decreaseddeterminantsofmyocardialoxygendemand[28],*improvedmyocardialbloodflow[29,30]andleftventricularfunction[31],*reducedthrombotic-relatedcomplications[32].*reduceheartrateandoccurrenceofarrhythmiasduringmanipulationoftheheart[33,34].7677二、通氣方式的選擇

容量控制性通氣（VolumeControlledVentilation,VCV）壓力控制性通氣（Pressurecontrolledventilation,PCV）

78二、通氣方式的影響

40例患者隨機分成四組Vt6ml/kgVt8ml/kgVt10ml/kgVt6ml/kg+CPAP0.2kPa

馬武華等.中山大學學報,2003,24(1)79

通氣方式的影響

2006Feb;19(1):1-4.

Hypoxemiaisconsideredtobethemostimportantchallengeduringone-lungventilation.Recentstudies,however,haveshownthatone-lungventilationcaninvolvesomelungdamageandcanthereforebeperseacauseofhypoxemia.RECENTFINDINGS:Ithasbeenshownthatsomeparametersofone-lungventilationareassociatedwithanincreasedprobabilityoflunginjury.

Hightidalvolumescantriggeranincreaseinsomeinflammatorymediatorsinbothexperimentalandclinicalsettings.Highinspiratorypressuresand/oracollapseofalveoliineveryrespiratorycyclewouldleadnotonlytoanimpairmentofoxygenation,butalsotoafurtherincidenceof'postpneumonectomypulmonaryedema',theearlierdefinitionoflunginjuryassociatedwithone-lungventilation.SUMMARY:Hypoxemiashouldalwaysbeconsideredasthemostimportantchallengeduringone-lungventilation.Oneshouldalsokeepinmind,however,thatsomeventilatorystrategiescanevenbeharmful.80Comparisonvolumecontrolledwithpressurecontrolledventilationduringone-lunganaesthesia.o

BrJAnaesth.1997Sep;79(3):306-10f

48例患者先行雙肺VCV,隨機分成2組.,V-P組:即單肺先行VCV,然后PCV.P-V組:剛好相反Weobservedthatpeakairwaypressure(P=0.000001),plateaupressure(P=0.01)andpulmonaryshunt(P=0.03)weresignificantlyhigherduringVCV,whereasarterialoxygentension(P=0.02)wassignificantlyhigherduringPCV.Peakairwaypressure(Paw)decreasedconsistentlyduringPCVineverypatientandthepercentagereductioninPawwas4-35%(mean16.1(SD8.4)%).Arterialoxygentensionincreasedin31patientsusingPCVandtheimprovementinarterialoxygenationduringPCVcorrelatedinverselywithpreoperativerespiratoryfunctiontests.

WeconcludethatPCVappearedtobeanalternativetoVCVinpatientsrequiringone-lunganaesthesiaandmaybesuperiortoVCVinpatientswithrespiratorydisease..

81結(jié)果

TLV-VCVOLV-VCVOLV-PCVTV708714710PaO227.528.432.3Qs/Qt16.740.2

36.2Paw21.428.3

23.682二、通氣方式:PCV對VCV

PCV在氣道內(nèi)峰壓(PCV可降低4%-35%)平臺壓肺內(nèi)分流三方面低于VCV83二、通氣方式:PCV對VCVPCV機制:降低了吸入氣體的流速，有利于氣體在肺內(nèi)的分布降低Paw有利于術(shù)側(cè)肺血流向通氣側(cè)肺再分布

減少肺部氣壓傷的發(fā)生率

TUGRUL.M等BrJAnaesth.1997Sep;79(3):306-10.

84Pressure-controlledversusvolume-controlledone-lungventilationforMIDCAB.ThoracHeimbergCCardiovascSurg.2006Dec;54(8):516-20.

Westudied50patientsundergoingthoracotomyandone-lungventilationbecauseofcardiovasculardisease.Aftertwo-lungventilationwithvolume-controlledventilation,patientsweredividedrandomlyintotwogroups.Inonegroup,ventilationwasswitchedtopressure-controlledventilationafterstartingone-lungventilation.Intheothergroup,volume-controlledventilationwascontinued.Parametersofventilation,pulmonaryfunctionandsystemicandpulmonaryhemodynamicswererecorded.Weobserved,thatpeakairwaypressure,deadspaceventilationandarterialcarbondioxidepartialpressureweresignificantlyhigherduringvolume-controlledventilation.Afterone-lungventilationpatientswithpressurecontrolledventilationhadloweralveolar-arterialoxygentensiondifferenceandahigherarterialoxygenpartialpressurewithsignificantdifferencesforthosepatientsintheintensivecareunit.

Weconcludethatpressure-controlledventilationmaybeusefultoimprovegasexchangeandalveolarrecruitmentduringonelungventilation.85Pressure-controlledversusvolume-controlledventilationduringone-lungventilationforthoracicsurgery.AnesthAnalg.UnzuetaMC,2007May;104(5):1029-33

Fifty-eightpatientswithgoodpreoperativepulmonaryfunctionscheduledforthoracicsurgerywereprospectivelyrandomizedintotwogroups.ThoseingroupAunderwentOLVinitiallywithVCVfor30minfollowedbyPCVforasimilarperiodoftime.ThoseingroupBunderwentOLVinitiallywithPCVfor30minfollowedbyVCVforasimilarduration.AirwaypressuresandarterialbloodgaseswereobtainedduringOLVattheendofeachventilatorymode.RESULTS:TherewerenodifferencesduringOLVinarterialoxygenationbetweenVCV(Pao2,206.1+/-62.4mmHg)andPCV(Pao2,202.1+/-56.4mmHg;P=0.534).PeakairwaypressurewaslowerwithPCVthanwithVCV(24.43+/-3.42cmH2Ovs.34.16+/-5.21cmH2O;P<0.001).

CONCLUSIONS:TheuseofPCVduringOLVdoesnotleadtoimprovedoxygenationduringOLVcomparedwithVCVforpatientswithgoodpreoperativepulmonaryfunction,butPCVdidleadtolowerpeakairwaypressures.86三、體位的選擇

平臥supineposition

半側(cè)semilateraldecubitusposition側(cè)臥lateraldecubitusposition87

Sequentialchangesofarterialoxygentensioninthesupinepositionduringone-lungventilation.

AnesthAnalg.2000Jan;90(1):28-34.目的:評價手術(shù)體位在單肺通氣期間對低氧血癥的影響.方法:33病人隨機分成3組,仰臥(SP)11,左半側(cè)臥(LSD)9,左側(cè)臥(LLD)13.在單肺通氣期間每5分鐘測一次血氣.如果SpO2下降到90%就轉(zhuǎn)為雙肺通氣結(jié)果:1仰臥組,30min要停止單肺通氣的達到82%,PaO2最低

左半側(cè)臥11%

左側(cè)臥

8%

2Pa02降到200mmHg三組所用的時間

仰臥354s,左半側(cè)臥583s,左側(cè)臥798s.SPPa02降到100mmHg794s

88機制

WhenthenondependentlungisnotventilatedintheLLD,bothHPVandgravitywouldcooperatetoreducepulmonarybloodflowinthenondependentlungfrom40%to20%oftotalbloodflow.However,theshiftofpulmonarybloodflowbygravityisnotexpectedintheSP,becausethereisnoverticaldistancebetweenventilatedandnonventilatedlungs.

在左側(cè)臥位時，在HPV和重力的共同作用下，非通氣側(cè)的血流可從40%減少為20%。而仰臥位時，重力作用就不起作用了。89Effectsofhead-downtiltonintrapulmonaryshuntfractionandoxygenationduringone-lungventilationinthelateraldecubitusposition.

ChoiYS,JThoracCardiovascSurg.2007Sep;134(3):613-8.

目的:研究在側(cè)臥位單肺通氣頭低斜位時對肺內(nèi)分流和氧合的影響.方法:34個單肺通氣病人隨機分成2組,對照組17和頭低斜位組17分別在單肺通氣15min(基礎(chǔ)值),在頭低100C斜位5minT5,10minT10和水平位10min時T20測定病人的血液動力學和呼吸的變化.對照組在同樣時間進行測量.結(jié)果:1頭低斜位組,心臟充盈壓增加,心臟指數(shù)不變.2頭低斜位組,在T10andT20和基礎(chǔ)值的肺內(nèi)分流的百分比變化是顯著升高,T5,T10,andT20和基礎(chǔ)值動脈氧分壓的百分比變化是顯著降低,.而對照組僅在T20時降低.CONCLUSION:Head-downtiltduringone-lungventilationinthelateraldecubituspositioncausedasignificantincreaseinshuntandadecreaseinpercentchangeofarterialoxygentension,withoutcausingdangeroushypoxemia.90四、不同的氧濃度的影響

Ventilation-perfusiondistributionandshuntfractionduringone-lungventilation:effectofdifferentinhaledoxygenlevels.ChinJPhysiol.2008,29;51(1):48-53Sixpigs,weighing27to34kg,wereselectedforthisstudy.Followingbyasteady-stateperiod,randomizedadministrationsofF(I)O2with0.4,0.6and1.0wereperformedfor30minutesattherightlateraldecubituspositionduringOLV,

atdifferentF(I)O2,therewerenosignificantchange