術(shù)前體位改變對剖宮產(chǎn)腰麻后引起低血壓的預(yù)測分析

陳燁　鄒聰華　陳彥青

【摘要】 目的：探索術(shù)前體位改變引起的心率變異性能否預(yù)測剖宮產(chǎn)腰麻后的低血壓。方法：隨機選擇50例產(chǎn)婦在腰麻下進行擇期剖宮產(chǎn)術(shù)，在剖宮產(chǎn)前1 d進行了體位變化檢查。按仰臥位、左側(cè)臥位和仰臥位的順序記錄無創(chuàng)血壓（NIBP）、心率（HR）、心電圖（ECG）和LF/HF比。采用5 min記錄1次參數(shù)，在每個位置記錄BP 3次，持續(xù)監(jiān)測心電圖。為了分析心率變異性，從監(jiān)護儀獲得ECG信號，并將其輸入到計算機中以分析RR間期。使用MemCalc軟件進行心率變異性（HRV）分析，每5秒計算1次LF、HF和LF/HF（低高頻率比），在第1次仰臥位記錄的LF/HF值作為對照值（基線LF/HF）。從左側(cè)臥位到仰臥位時，LF/HF比增長2倍以上的產(chǎn)婦分到陽性組，2倍以下分到陰性組。手術(shù)當(dāng)天的產(chǎn)婦均進行ECG、HR、NIBP和氧飽和度的監(jiān)測，并在仰臥位靜脈滴注晶體液[4～6 mL/（kg·h）]。產(chǎn)婦仰臥時測的HR和BP為基線值。取左側(cè)臥位，L3～4間隙進行腰麻，藥物為0.75%羅哌卡因2 mL，注射后產(chǎn)婦轉(zhuǎn)為平臥位。每分鐘測量無創(chuàng)血壓，直到血壓平穩(wěn)。結(jié)果：根據(jù)體位改變檢測結(jié)果，將產(chǎn)婦分為陽性組（23例）和陰性組（26例），71.4%（35/49）產(chǎn)婦發(fā)生低血壓，陽性組占60.0%（21/35），陰性組占40.0%（14/35）。PCT陽性組低血壓發(fā)生率為91.3%（21/23），高于陰性組的53.8%（14/26），差異有統(tǒng)計學(xué)意義（P<0.01）。在腰麻（SA）剖宮產(chǎn)期間，PCT預(yù)測產(chǎn)婦低血壓的敏感性和特異性分別為60.0%[95%CI（52.4，62.3）]和87.5%[95%CI（63.5，98.2）]。PCT的陽性預(yù)測值（PPV）和陰性預(yù)測值（NPV）分別為91.3%[95%CI（52.4，62.3）]和53.8%[95%CI（37.6，55.7）]。PCT作為產(chǎn)婦低血壓的預(yù)測因子為0.76[95%CI（0.60，0.92）]。結(jié)論：術(shù)前體位改變引起的心率變化可預(yù)測剖宮產(chǎn)腰麻后低血壓。

【關(guān)鍵詞】 低血壓； 心率變異性； 體位改變試驗； 剖宮產(chǎn)

Prediction of Hypotension during Spinal Anesthesia for Elective Cesarean Section by Altered Heart Rate Variability Induced by Postural Change/CHEN Ye，ZOU Cong-hua，CHEN Yan-qing.//Medical Innovation of China，2017，14（30）：019-022

【Abstract】 Objective：To investigate the effect of the postural change test with heart rate variability to predict the risk of hypotension during spinal anesthesia for cesarean section.Method：A total of 50 women scheduled to undergo cesarean section under spinal anesthesia were enrolled，a postural change test was performed the day before cesarean section.Non-invasive BP （NIBP） on the left arm，HR，electrocardiogram （ECG） and LF/HF ratio were recorded in the order of supine position，left lateral position and supine position.Each position was adopted for 5 min to record each parameter，blood pressure was recorded three times in each position，the ECG and HR were continuously monitored.In order to analyze heart rate variability，the ECG signal was obtained from the monitor and input into the computer to analyze the RR interval.Heart rate variability （HRV） analysis was performed using MemCalc software，the first time LF，HF and LF/HF （low to high frequency ratio） were calculated every 5 seconds，and the LF/HF value recorded in the first supine position was used as the control value （baseline LF/HF）.From left recumbent position to supine position，LF/HF was more than 2 times allocated to the positive group，less than 2 times allocated to the negative group.On the operating day，all patients were monitored via ECG，HR，NIBP，oxygen saturation，and received intravenous crystalloid [4-6 mL/（kg·h）] in the supine position.We regarded HR and BP measured in the operating room just after lying supine on the operating room bed as baseline values.In all cases，SA was performed at the L3-4 interspace with the patient in the left lateral position.Hyperbaric 0.75% Ropivacaine 2 mL was administered through a spinal needle.Following injection，patients were immediately turned supine from the left lateral position，non-invasive BP was measured every minute until BP stabilized.Result：According to the result of body position change test，the pregnant women were divided into positive group （23 cases） and negative group （26 cases），71.4%（35/49） of maternal hypotension occurred，the positive group accounted for 60.0%（21/35），the negative group accounted for 40.0%（14/35）.The incidence of hypotension in PCT positive group was 91.3%（21/23），which was higher than 53.8%（14/26） in negative group，the difference was statistically significant（P<0.01）.Sensitivity and specificity of the PCT to predict maternal hypotension during cesarean section under SA were 60.0%[95%CI（52.4，62.3）] and 87.5%[95%CI（63.5，98.2）] respectively.Positive predictive value （PPV） and negative predictive value （NPV） of the PCT was 91.3%[95%CI（52.4，62.3）] and 53.8%[95%CI（37.6，55.7）]，respectively.PCT as a predictor of maternal hypotension was 0.76[95%CI （0.60，0.92）].Conclusion：The change of heart rate caused by the change of body position before operation can predict hypotension after cesarean section.endprint

【Key words】 Hypotension； Heart rate variability； Postural change test； Cesarean section

First-authors address：The Fujian Provincial Jinshan Hospital，F(xiàn)uzhou 350000，China

doi：10.3969/j.issn.1674-4985.2017.30.006

腰麻是剖宮產(chǎn)手術(shù)常見的麻醉方法[1]，但腰麻后妊娠子宮壓迫腹部大血管可引起產(chǎn)婦低血壓，導(dǎo)致產(chǎn)婦和胎兒出現(xiàn)一系列問題，如惡心、嘔吐、胎兒窘迫等[2-4]。因此預(yù)防產(chǎn)婦出現(xiàn)低血壓是非常必要的。之前已有多種方法來預(yù)測剖宮產(chǎn)腰麻后產(chǎn)婦低血壓，包括脈搏變異指數(shù)、腦氧飽和度（SCO2）和術(shù)前體位改變引起的心率變化[5-10]，但預(yù)防效果均較差。……