预防剖宫产术仰卧位低血压综合征的研究进展

仰卧位低血压综合征（supine hypotensive syndrome，SHS）是剖宫产术中常见的并发症．严重的低血压可能导致产妇恶心呕吐。甚歪意识丧失，而且低血压还可以造成子宫胎盘血流灌注的急速下降．妨碍胎盘的血气交换。引起胎儿缺氧、酸中毒甚至中枢神经系统损伤等严重后果。本文就预防剖宫产术仰卧位低血压综合征的研究进展作一综述。     

剖宫产术仰卧位低血压综合征的临床观察和分析

目的探讨剖宫产术中仰卧位低血压综合征的临床观察和预防方法。方法对152例发生仰卧位低血压综合征的病例，就麻醉成功后发生时间、血压下降程度、对升压药的反应、体位变化等方面进行了临床分析。结果仰卧位低血压患者均得到有效预防及控制。结论产妇在麻醉后取仰卧左倾15°～30°的体位可以有效预防并减少仰卧位低血压综合征的发生。     

剖宫产术中实施体位干预对仰卧位低血压综合征的影响

目的探讨剖宫产术中实施体位干预的作用,以预防仰卧位低血压综合征的发生。方法选择224例行子宫下段剖宫产的产妇,随机分为2组,对照组剖宫产术中常规采取平卧位,干预组麻醉后即采取左倾25°～30°的仰卧位,常规心电监护,观察病情变化并记录。结果对照组仰卧位低血压综合征发生率明显高于干预组,且程度更重,持续时间更长。结论剖宫产术中实施体位干预能有效的预防仰卧位低血压综合征的发生。     

硬膜外麻醉剖宫产术中“产妇仰卧位低血压综合征”的防治

在硬膜外麻醉下施行刮宫产术，较易出现“产妇仰卧位低血压综合征(SHS)”，发生率达5％-80％。对母婴安全有严重威胁。因此，探索SHS的发生因素以及预防措施，具有实际意义。我院在1999年-2002年期间采用硬膜外麻醉施行剖宫产术共209例。其中64例出现SHS。     

变换体位引起的血压改变预测剖宫产腰麻仰卧位低血压综合征的发生

目的观察产妇麻醉前变换体位引起的血压变化预测腰麻后仰卧位低血压综合征(SHS)的发生情况。方法 ASAⅠ或Ⅱ级正常足月妊娠行剖宫产手术的产妇58例,麻醉前测仰卧位和侧卧位MAP,计算两者血压差值,观察麻醉后1、3、5 min MAP和HR的变化,MAP差值的大小与低血压发生率之间的关系。结果引起术中发生低血压的麻醉前仰卧位和侧卧位MAP平均差值为11.2 mm Hg,低血压平均发生率为39.9%。差值越大术中低血压的发生率越高(P<0.05)。结论体位引起的MAP差值越大,术中发生低血压的风险越高,为麻醉医师术中有效预防SHS的发生提供了依据。     

剖腹产术中“仰卧位低血压综合征”的护理

妊娠期所发生的循环系统最明显的变化是在前几个月心搏量增加30～40％。母体休息时心搏量在怀孕20～24周达最高,妊娠后期由于子宫增大压迫下腔静脉及主动脉远端与髂动脉,而使心搏量减少,特别在产前仰卧位时可致回心血流受阻,心输出量骤然减少,而出现“仰卧位低血压综合征”。我院1985年5月～1986年5月行109例剖腹产,曾遇本综合征7例,发生率为6.4％,局麻加强化39例发生1例,硬膜外麻醉70例发生6例。现将术中对患者     

高渗氯化钠羟乙基淀粉40注射液防治产妇仰卧位低血压综合征

目的观察预输注高渗氯化钠羟乙基淀粉40注射液(HSS 40)对产妇仰卧位低血压综合征的防治效果。方法行剖宫产产妇180例,随机均分为三组:W组输注6%羟乙基淀粉130/0.4氯化钠注射液250 ml;H组输注HSS 40 250 ml;N组输注生理盐水250 ml。均于硬膜外麻醉穿刺成功后30 min内输完。于输液前、输液后30 min、术后1 d采集产妇静脉血及脐动脉血检测电解质,记录术中及术后24 h尿量。观察仰卧位低血压综合征的发生情况并记录新生儿1 min Apgar评分。结果仰卧位低血压发生率W组(8.3%)和H组(6.7%)显著低于N组(18.3%)。H组术后24 h尿量显著多于W组和N组(P<0.05)。结论 HSS 40预输注可有效防治产妇仰卧位低血压综合征发生,对胎儿无不良影响。     

预先经皮电刺激内关穴预防蛛网膜下腔阻滞剖宫产产妇术中低血压

目的 探讨预先电刺激内关穴预防蛛网膜下腔阻滞剖宫产术中低血压的效果.方法 选择择期在蛛网膜下腔阻滞下行剖宫产术的单胎足月妊娠产妇90例,年龄18～35岁,ASAⅡ或Ⅲ级,孕37～42周.随机分为三组:A组、B组和C组,每组30例.A组不给予电刺激;B组在蛛网膜下腔阻滞前20 min(摆左侧卧位)开始接受电刺激(连续波、...     

小剂量麻黄碱硬膜外麻醉下剖宫产手术中预防低血压的作用

硬膜外麻醉是剖宫产手术较常用的一种麻醉方式,而低血压在硬膜外麻醉较为常见,发生率达5%～80%。产妇特别是有仰卧位低血压综合征（SHS）的产妇出现低血压,可导致子宫血流量减少、酸血症、胎盘缺氧和胎儿宫内窘迫。因此麻醉手术期间有效地预防低血压的发生对母婴极为重要。     

麻醉后仰卧位低血压综合征对新生儿的影响

近年来随着手术、麻醉、输血、抗感染技术的日益进步,剖宫产已成为解决难产和某些高危妊娠、挽救孕产妇和围生儿生命常用的有效手段,但麻醉后仰卧位低血压综合征引起新生儿窒息的比率及程度有多少,现就我院剖宫产时发生的150例仰卧位低血压综合征报道如下.     

Colloid vs. crystalloid preloading to prevent maternal hypotension during spinal anesthesia for elective cesarean section

Background:  Hypotension associated with spinal anesthesia for cesarean section is still a clinical problem. Colloid solutions seem preferable to crystalloid solutions for preloading. In most studies the overall rate of hypotension is reported. Few studies have, however, investigated the maternal and neonatal consequences of different levels of maternal hypotension.
Methods:  In this randomized, double-blinded study 110 patients presenting for elective cesarean section received either 1000 ml acetated Ringer's solution or 1000 ml 3% dextran 60 solution immediately before spinal anesthesia. The effect on overall hypotension, clinically significant hypotension (hypotension associated with maternal discomfort defined as nausea, retching/vomiting, dizziness or chest symptoms) and severe hypotension (systolic arterial pressure <80 mmHg) was studied.
Results:  Dextran reduced the incidence of overall hypotension from 85 to 66% ( P =  0.03), reduced the incidence of clinically significant hypotension from 60 to 30% ( P =  0.002) and reduced the incidence of severe hypotension from 23 to 3.6% ( P =  0.004) compared to Ringer's solution. There were neither differences in neonatal outcome between treatment groups nor between neonates grouped after severity of maternal hypotension.
Conclusion:  Clinically significant hypotension seems to be a more suitable outcome variable than overall hypotension. The protective effect of the colloid solution increased with increased severity of hypotension.     

Postural change from lateral to supine is an important mechanism enhancing cephalic spread after injection of intrathecal 0.5% plain bupivacaine for cesarean section

BackgroundSpinal anesthesia is widely used for cesarean section, but the factors that affect the spread of the block in pregnant patients are still not fully explained. This study was designed to investigate the effect of postural changes on sensory block level.MethodsThirty patients scheduled for elective cesarean section under combined spinal–epidural anesthesia were randomly allocated into three groups. After intrathecal injection of 0.5% plain bupivacaine 7.5 mg, patients in group S were immediately placed in the supine position with left tilt, patients in group L5 were kept lateral for 5 min and then turned to the supine position with left tilt, and patients in group L10 were kept lateral for 10 min and then turned to the supine position with left tilt.ResultsAt 5 min, median cephalad level of sensory block was lower in groups L5 and L10 compared with group S (corrected P<0.001); at 10 min, median cephalad sensory block level was lower in group L10 compared with group S (corrected P<0.001) and group L5 (corrected P<0.001), and lower in group L5 compared with group S (corrected P=0.033); at 15 min, median cephalad level of sensory block was lower in group L10 compared with group S (corrected P=0.003) and group L5 (corrected P=0.015).ConclusionsIn our population, using 0.5% plain bupivacaine 7.5 mg, postural change from the lateral position to the supine position is an important mechanism enhancing cephalic spread of spinal anesthesia during late pregnancy.