术前体位改变对剖宫产腰麻后引起低血压的预测分析【摘要】目的：探索?g前体位改变引起的心率变异性能否预测剖宫产腰麻后的低血压。方法：随机选择50例产妇在腰麻下进行择期剖宫产术，在剖宫产前1d进行了体位变化检查。按仰卧位、左侧卧位和仰卧位的顺序记录无创血压（NIBP）、心率（HR）、心电图（ECG）和LF/HF比。采用5min记录1次参数，在每个位置记录BP3次，持续监测心电图。为了分析心率变异性，从监护仪获得ECG信号，并将其输入到计算机中以分析RR间期。使用MemCalc软件进行心率变异性（HRV）分析，每5秒计算1次LF、HF和LF/HF（低高频率比），在第1次仰卧位记录的LF/HF值作为对照值（基线LF/HF）。从左侧卧位到仰卧位时，LF/HF比增长2倍以上的产妇分到阳性组，2倍以下分到阴性组。手术当天的产妇均进行ECG、HR、NIBP和氧饱和度的监测，并在仰卧位静脉滴注晶体液[4～6mL/（kg?h）]。产妇仰卧时测的HR和BP为基线值。取左侧卧位，L3～4间隙进行腰麻，药物为0.75%罗哌卡因2mL，注射后产妇转为平卧位。每分钟测量无创血压，直到血压平稳。结果：根据体位改变检测结果，将产妇分为阳性组（23例）和阴性组（26例），71.4%（35/49）产妇发生低血压，阳性组占60.0%（21/35），阴性组占40.0%（14/35）。PCT阳性组低血压发生率为91.3%（21/23），高于阴性组的53.8%（14/26），差异有统计学意义（P<0.01）。在腰麻（SA）剖宫产期间，PCT预测产妇低血压的敏感性和特异性分别为60.0%[95%CI（52.4，62.3）]和87.5%[95%CI（63.5，98.2）]。PCT的阳性预测值（PPV）和阴性预测值（NPV）分别为91.3%[95%CI（52.4，62.3）]和53.8%[95%CI（37.6，55.7）]。PCT作为产妇低血压的预测因子为0.76[95%CI（0.60，0.92）]。结论：术前体位改变引起的心率变化可预测剖宫产腰麻后低血压。【关键词】低血压；心率变异性；体位改变试验；剖宫产PredictionofHypotensionduringSpinalAnesthesiaforElectiveCesareanSectionbyAlteredHeartRateVariabilityInducedbyPosturalChange/CHENYe，ZOUCong-hua，CHENYan-qing.//MedicalInnovationofChina，2017，14（30）：019-022【Abstract】Objective：Toinvestigatetheeffectoftheposturalchangetestwithheartratevariabilitytopredicttheriskofhypotensionduringspinalanesthesiaforcesareansection.Method：Atotalof50womenscheduledtoundergocesareansectionunderspinalanesthesiawereenrolled，aposturalchangetestwasperformedthedaybeforecesareansection.Non-invasiveBP（NIBP）ontheleftarm，HR，electrocardiogram（ECG）andLF/HFratiowererecordedintheorderofsupineposition，leftlateralpositionandsupineposition.Eachpositionwasadoptedfor5mintorecordeachparameter，bloodpressurewasrecordedthreeineachposition，theECGandHRwerecontinuouslymonitored.Inordertoanalyzeheartratevariability，theECGsignalwasobtainedfromthemonitorandinputintothecomputertoanalyzetheRRinterval.Heartratevariability（HRV）analysiswasperformedusingMemCalcsoftware，thefirsttimeLF，HFandLF/HF（lowtohighfrequencyratio）werecalculatedevery5seconds，andtheLF/HFvaluerecordedinthefirstsupinepositionwasusedasthecontrolvalue（baselineLF/HF）.Fromleftrecumbentpositiontosupineposition，LF/HFwasmorethan2allocatedtothepositivegroup，lessthan2allocatedtothenegativegroup.Ontheoperatingday，allpatientsweremonitoredviaECG，HR，NIBP，oxygensaturation，andreceivedintravenouscrystalloid[4-6mL/（kg?h）]inthesupineposition.WeregardedHRandBPmeasuredintheoperatingroomjustafterlyingsupineontheoperatingroombedasbaselinevalues.Inallcases，SAwasperformedattheL3-4interspacewiththepatientintheleftlateralposition.Hyperbaric0.75%Ropivacaine2mLwasadministeredthroughaspinalneedle.Followinginjection，patientswereimmediatelyturnedsupinefromtheleftlateralposition，non-invasiveBPwasmeasuredeveryminuteuntilBPstabilize...