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最近,中国麻醉医师术中TEE推广培训协作组提出了适用于麻醉急诊和术中循环监测的TEE-FOCUS/TTEFOCUS的概念,其基本切面有5个,切面的选择上有别于急诊常用的4个FATE基本切面,临床实践证明适用于术中循环的监测(图2)。
TEE-FOCUS/TTE-FOCUS涉及到5个基本切面中有4个关于心脏的基本切面和1个关于大血管的基本切面:1. 经胃底心室短轴切面,2. 食管中段四腔心切面,3. 左心室长轴切面,4. 右心室流入流出道切面,5. 腹主动脉和或下腔静脉短轴切面。
为了有效地推广TEE-FOCUS/TTE-FOCUS中关于心脏的标准切面,我们与中科院成都信息技术有限公司合作,推出了基于Android平台的手机APP教学软件(维思模-Vrsim)。
(二)标准化切面的应用
合理应用这些切面可有效地监测术中的循环事件,例如:骨科和泌尿外科手术常见的肺动脉栓塞,开颅手术常见的气体栓塞,低血容量,整体和局部左心功能评价,右心功能评价,基本的瓣膜疾病,成人简单的先心病,心包填塞,胸部创伤等如下所述。
1. 左心室长轴切面(图2基本切面左上):(1)左心房大小、房壁厚度是否正常,舒缩运动是否正常;(2)二尖瓣开闭运动是否正常,有无穿孔及赘生物;(3)左心室流入道是否通畅;(4)左心室,室壁厚度是否正常,舒缩运动是否正常;(5)左心室流出道是否有梗阻;(6)主动脉瓣开闭是否正常,有无赘生物;(7)升主动脉管壁、管腔是否正常;(8)腔内血流是否正常。
2. 右室流入流出道切面(图2基本切面右上):(1)右心房大小、房壁厚度是否正常,舒缩运动是否正常;(2)三尖瓣开闭运动是否正常,有无穿孔及赘生物;(3)右心室流入道是否通畅;(4)右心室大小,室壁厚度是否正常,舒缩运动是否正常;(5)右心室流出道是否有梗阻;(6)肺动脉瓣开闭是否正常,有无赘生物;(7)肺动脉管壁、管腔是否正常;(8)腔内血流是否正常。
3. 经胃左心室短轴切面(图2基本切面左下):(1)左、右心室腔大小及形态;(2)左、右心室比例及室间隔凸向哪一侧;(3)室壁厚度和搏动幅度;(4)腔内血流是否正常。
4. 食管中段四腔心切面(图2基本切面右下,图4):(1)各房室大小及其比例;(2)切面中心室壁的厚度、搏动幅度、连续性;(3)二尖瓣和三尖瓣的形态结构和开闭功能;(4)腔内血流是否正常。
5. 降主动脉短轴切面(图3右下):(1)降主动脉管腔大小及形态;(2)主动脉壁各层是否增厚,回声增强;(3)是否存在夹层或假性动脉瘤;(4)腔内血流是否正常。
二、从标准化切面和标准化测量中提取影像学特征
术中时间有限,需要麻醉医师迅速决定,往往来不及做精确的测量,所以我们首先应该明确要测什么,其次是怎么测量的问题。超声监测循环功能用到的参数不外乎壁、腔、瓣、流四个方面,壁就是房壁、室壁、血管壁,腔就是心房、心室腔和血管腔,瓣就是房、室之间的两个房室瓣、心室和大动脉之间的两个半月瓣,流就是心血管的正常和各种异常血流[11]。其基本的定性指标如表1,超声评价循环功能最重要的是将患者的心血管特征提取出来,用病理生理学模型解释,然后用于诊疗决策。
以左心室中段短轴切面为例,在这个切面上,可以观察左、右心室的心腔大小,室壁厚度。左心室正常值男性55 mm,女性50 mm,正常情况下左心室和右心室的比例关系大约是5∶2;而左心室舒张末面积(LVEDA)和左心室收缩末面积(LVESA)的比例大致是2∶1,我们将正常比例的心室舒缩关系形象而有趣地描述为“大眼瞪小眼”,还可以描述“大眼瞪大眼”为心衰,“小眼瞪小眼”为容量不足[12],室颤时心室舒缩功能丧失,趣称为“干瞪眼”。(图5)
生理学中左心室有两条曲线,心室的容积-时间曲线和压力-时间曲线,左心室容积-时间曲线的最大值点对应着左心室舒张末容积,最小值点对应着左心室收缩末容积,最大值点和最小值点之间的差值间接或直接地反映每博输出量(SV)。EF(射血分数)=SV/心室舒张末容积。术中直接监测LV心室舒张末容积尚不容易,直接测量LV心室舒张末容积要用实时三维超声心动图技术、二维图像自动分割技术、结合辛普森法计算得到,这种方法用在术中直接监测左心室的容积-时间曲线成本较高。如果心室形态正常,我们还是推荐用M型超声测量LVEDD/LVESD,计算FS(FS=LVEDD-LVESD/LVEDD)或者左心室中段短轴2D切面测量计算FAC=LVEDA-LVESA/LVEDA;EF≈2FS。
三、从超声影像学特征出发从而建立个体化的病理生理模型
(一)超声循环监测的正常值
正常值是描述正常心脏结构和功能的基础,最重要的参数莫过于心血管腔的内径和房室、血管壁的厚度。通过将测量值与正常值(表2)作出比较,即可以提取心血管的影像学特征。
(二)常见的循环系统病理类型的超声形态特征
有了正常值,就可以对常见的循环系统病理类型进行区分和归纳,下面阐述常见的循环系统病理类型的超声形态特征与常见病理类型的关系[13]。
1. 心室腔小壁厚:左室长轴、短轴切面,可见室壁增厚,心腔缩小(图6上左、右)常见于高血压病,主动脉瓣狭窄,左室流出道梗阻,肥厚型心肌病,心肌糖原沉积病;右室肥厚-法洛氏四联症,肺动脉闭锁,肺动脉高压。
肥厚心室的顺应性降低,前负荷对心房收缩功能的依赖性增加,心肌氧供对后负荷依赖性增加,硬膜外或腰麻可降低外周血管阻力,如盲目进行麻醉可能带来灾难性后果。一般情况下不需要主动增强心肌收缩力,合并流出道梗阻还要减低心肌收缩力,增加外周血管阻力(图6红色箭头所示)和血容量。
2. 左心室腔大壁薄:心尖四腔、心室短轴切面,心腔扩大,室壁变薄,搏幅减低,这类心脏左室舒张末压升高(图7红色箭头所示),造成冠脉灌注压降低,心肌缺血。这类患者若诱导期如出现心跳骤停,心肺复苏极为困难。常见于扩张型心肌病,主动脉瓣反流,缺血性心肌病,容量过负荷等。处理上要保持心率/律稳定,合适的前负荷,减轻后负荷,增强心肌收缩力。
3. 右房右室大,左房左室小(图8):肺栓塞,右室心梗,肺动脉高压,大房缺,二尖瓣狭窄晚期,三尖瓣重度反流,肺静脉异位引流。这类心脏右心室舒张末压升高,如遇到左房压急性升高的因素(急性左心衰、突发心房颤动、二尖瓣急性关闭不全),发生心跳骤停的风险很高。
四、常见心脏病的超声影像特征
(一)单纯瓣膜病的超声影像特征
单纯瓣膜病术中管理风险由大到小依次为:主动脉瓣反流,主动脉瓣狭窄,二尖瓣反流,二尖瓣狭窄。其超声影像特征见表3。
(二)常见先心病的超声影像特征
常见的先天性疾病按照病理生理学特征可分为两种类型,“肺血多”型和“肺血少”型(图9)。两类疾病的超声要点、麻醉要点和外科要点都有各自的特点。
1. 以肺血多为主要表现的疾病有:房间隔缺损,室间隔缺损,动脉导管未闭[14,15],主、肺动脉窗等疾病。早期表现为左向右分流(图10中虚线所示),胸片显示肺纹理增多。虚线表示相应心血管节段存在无效循环,无效循环经过的心、血管腔增大,无效循环未经过的心血管腔不增大。肺充血后血管床扩张,容易发生感染和急性肺动脉高压危象。体外循环术后容易发生鱼精蛋白过敏,严重者甚至会发生心脏停搏。
房间隔缺损、室间隔缺损、动脉导管未闭的患者长期肺充血可导致肺动脉高压,肺小动脉管壁增厚、闭塞直至艾森曼格综合征。艾森曼格综合征的患者行剖宫产手术时要注意维持体循环阻力和血容量,降低肺循环阻力。
2. 以肺血少为主要表现的疾病有:法洛氏四联症、肺动脉闭锁等(图10)。这类疾病肺血管树发育差,胸片肺纹稀疏,早期表现为右向左分流,术中血氧饱和度下降的原因是体循环阻力下降,右向左分流增加,肺血减少,表现为“血压依赖性氧合”,如遇到右室流出道动力性梗阻,会出现严重的低氧血症,称为缺氧发作。“肺血少”的先心病通常无肺动脉高压,不容易发生鱼精蛋白过敏,不发生艾森曼格综合征,左房压低,左心室容积偏低,术后需要避免容量过负荷。这类患者因为肺血少,因此吸入麻醉效果差,由于在发育期间形成了大量的体肺侧枝(MAPCUS),增加肺血流量,这些侧枝循环在术后常会带来间质性肺水肿,因此需要做杂交手术,在矫正肺动脉狭窄/闭锁的同时行侧枝封堵。
五、小 结
循环功能监测是麻醉风险管理的重要内容(图11),将超声用于循环功能监测是麻醉学发展的需要,近年来,越来越多的麻醉医师认识到没有超声循环功能监测,心血管麻醉的安全将得不到保障。未来,超声快速评价和监测心血管功能将成为非心脏专科麻醉医师的必备能力。
我国临床超声监测技术的发展比较迅速,已经成立了中国麻醉医师术中TEE推广培训协作组,协作组在中华医学会麻醉学分会刘进主委的直接领导下,凝聚海内外华人麻醉医师的积极性和创造性,积极开展培训和推广工作[16],我们有理由相信,随着中国国力的增强和住院医师规范化培训的推进,临床超声在中国将出现多学科协作的新局面,全面推广将成为不可逆转的趋势。
参考文献
[1] Smith ZA, Wood D. Emergency focussed assessment with sonography in trauma(FAST) and haemodynamic stability. Emerg Med J, 2013, Feb 13
[2] Jensen MB, Sloth E, Larsen KM, Schmidt MB. Transthoracic echocardiography for cardiopulmonary monitoring in intensive care. Eur J Anaesthesiol, 2004 Sep, 21(9): 700-707
[3] Practice guidelines for perioperative transesophageal echocardiography. A report by the American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists Task Force on Transesophageal Echocardiography. Anesthesiology, 1996 Apr, 84(4): 986-1006
[4] Shanewise JS, Cheung AT, Aronson S et al. ASE/SCA guidelines for performing a comprehensive intraoperative multiplane transesophageal echocardiography examination: recommendations of the American Society of Echocardiography Council for Intraoperative Echocardiography and the Society of Cardiovascular Anesthesiologists Task Force for Certification in Perioperative Transesophageal Echocardiography. Anesth Analg, 1999 Oct, 89(4): 870-884
[5] Shiga T, Ogawa R. Five-grade scoring system is still confusing: does ASE/SCA set up a double standard? Anesth Analg, 2000 May, 90(5): 1248-1249
[6] Cahalan MK, Abel M, Goldman M, Pearlman A, Sears-Rogan P, Russell I, Shanewise J, Stewart W, Troianos C, American Society of Echocardiography, Society of Cardiovascular Anesthesiologists. American Society of Echocardiography and Society of Cardiovascular Anesthesiologists task force guidelines for training in perioperative echocardiography. Anesth Analg, 2002 Jun, 94(6): 1384-1388
[7] Cheitlin MD, Armstrong WF, Aurigemma GP, et al, ACC/AHA/ASE 2003 guideline update for the clinical application of echocardiography: summary article: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (ACC/AHA/ASE Committee to Update the 1997 Guidelines for the Clinical Application of Echocardiography). Circulation, 2003, 108: 1146-1162
[8] Mathew JP, Glas K, Troianos CA, Sears-Rogan P, Savage R, Shanewise J, Kisslo J, Aronson S, Shernan S, American Society of Echocardiography, Society of Cardiovascular Anesthesiologists. American Society of Echocardiography/Society of Cardiovascular Anesthesiologists recommendations and guidelines for continuous quality improvement in perioperative echocardiography.J Am Soc Echocardiogr, 2006 Nov, 19(11): 1303-1313
[9] American Society of Anesthesiologists and Society of Cardiovascular Anesthesiologists Task Force on Transesophageal Echocardiography. Practice guidelines for perioperative transesophageal echocardiography: An updated report by the American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists Task Force on Transesophageal Echocardiography. Anesthesiology, 2010, 112: 1084-1096
[10] Reeves ST, Finley AC, Skubas NJ, Swaminathan M, Whitley WS, Glas KE, Hahn RT, Shanewise JS, Adams MS, Shernan SK, Council on Perioperative Echocardiography of the American Society of Echocardiography, Society of Cardiovascular Anesthesiologists. Basic perioperative transesophageal echocardiography examination: a consensus statement of the American Society of Echocardiography and the Society of Cardiovascular Anesthesiologists. J Am Soc Echocardiogr, 2013 May, 26(5): 443-456
[11] Pai RG, Bansal RC, Shah PM. Doppler-derived rate of left ventricular pressure rise. Its correlation with the postoperative left ventricular function in mitral regurgitation. Circulation, 1990 Aug, 82(2): 514-520
[12] Vincent JL, De Backer D. Circulatory shock. N Engl J Med, 2013 Oct 31, 369(18): 1726-1734
[13] Leung JM, Levine EH. Left ventricular end-systolic cavity obliteration as an estimate of intraoperative hypovolemia. Anesthesiology, 1994 Nov, 81(5): 1102-1109
[14] Liu F, Hsiung MC, Song H, Dian K, Tang H, Liu J. Unexpected co-arctation ofaorta detected by transesophageal echocardiography during patent ductus arteriosus ligation. Front Med, 2013 Jun, 7(2): 270-273
[15]Song H, Liu F, Dian K, Liu J. Echo rounds: intraoperative transesophageal echocardiography-guided patent ductus arteriosus ligation in an asymptomatic nonbacterial endocarditis patient. Anesth Analg, 2010 Oct, 111(4): 878-880
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作者: 心超 时间: 2013-12-19 09:12
本帖最后由 心超 于 2013-12-19 09:15 编辑
关于急诊超声的国内外知识更新资源:
Emergency ultrasoundFrom Wikipedia, the free encyclopedia
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Emergency ultrasound is the application of ultrasound at the point of care to make immediate patient-care decisions. It is performed by the health care professional caring for the injured persons. This point-of-care use of ultrasound is often to evaluate an emergent medical condition, in settings such as an emergency department, critical care unit, ambulance, or combat zone.[1][2]
Contents [hide]
Setting[edit]
Emergency ultrasound is used to quickly diagnose a limited set of injuries or pathologic conditions,[3] specifically those where conventional diagnostic methods would either take too long or would introduce greater risk to a person (either by transporting the person away from the most closely monitored setting, or exposing them to ionizing radiation and/or intravenous contrast agents).[4][5]
Point of care ultrasound has been used in a wide variety of specialties and has increased in use in the last decade as ultrasound machines have become more compact and portable.[6] It is now used for a variety of exams in various clinical settings at the person's bedside. In the emergency setting, it is used to guide resuscitation and monitor critically ill persons, provide procedural guidance for improved safety and confirm clinical diagnosis.Scope[edit]Resuscitation of the critically ill[edit]
Point of care ultrasound is sometimes the only option in the evaluation of injured persons who are too ill for transport to other imaging modalities (i.e. computed tomography, or CT scan) or whose illness is so acute that medical decisions in their care need to be made in seconds to minutes. It is also increasingly used to guide and triage care in resource-limited situations, in rural or medically underserved areas.[7]
In people who present with a traumatic injury, The focused assessment with sonography for trauma or FAST exam is used to assess hypotensive person for occult bleeding. Traditionally used by emergency physicians and surgeons treating trauma persons, it has also been used by paramedics[8] in combat zones,[2] and for non-traumatic problems such as ruptured ectopic pregnancy. Similarly, emergency ultrasound can also evaluate the lungs for hemothorax (bleeding in the chest), and pneumothorax (a puncture resulting in air trapped in the chest and lung collapse).
People presenting with hypotension of unknown cause, ultrasound has been utilized to determine the cause of shock.[9][10] Evaluation of the heart and inferior vena cava (IVC) can help the clinician at the bedside choose important treatments and monitor the response to the interventions.[11][12]
A person who has hypotension and a bedside ultrasound showing hyperdynamic left heart with a flat, collapsible IVC indicates low blood volume. If the person also has a fever, the clinician may determine sepsis, or severe infection is causing the problem. If that same hypotensive person has back pain instead of a fever, the clinician may see an abdominal aortic aneurysm that is leaking or ruptured. Conversely, weak heart activity and a very full, non-collapsible IVC would indicate a cardiac cause for low blood pressure.
For those presenting with acute shortness of breath, ultrasound assessment of the lung, heart, and IVC can evaluate for potentially life threatening diseases including pneumothorax, significant pleural effusions, congestive heart failure, pulmonary edema, pericardial effusion, and some large pulmonary emboli.[11][13]
With its increased availability, ultrasound is now frequently used more in code situations, in which a person have lost most or all signs of life.[14] Practitioners may use the ultrasound to see if the heart is moving, beating in organized fashion or if it has a pericardial effusion or fluid around it. Pericardiocentesis, a procedure in which a needle is used to drain the effusion, can utilize ultrasound guidance of a needle to decrease the risk of hitting lungs, heart or other vital organs[15]Monitoring therapy[edit]
Emergency ultrasound can not only diagnose, but also monitor a persons response to therapeutic interventions. Ultrasound can be utilized to assess a persons intravascular volume status and response to intravenous fluid therapy by measuring the size and respiratory change in the diameter of the IVC.[11] Ultrasound of the lungs may demonstrate resolution of pulmonary edema from congestive heart failure.[16]Procedural guidance[edit]
Using ultrasound to guide needles during procedures may improve success and decrease complications in procedures performed by multiple specialties, including central[17] and venous access,[18][19] thoracentesis,[20] paracentesis, pericardiocentesis,[21] arthrocentesis, regional anesthesia, incision and drainage of abscesses,[22][23] localization and removal of foreign bodies, lumbar puncture, biopsies, and other procedures.[17]Diagnostic[edit]
Point-of-care ultrasound is being increasingly used to speed patient care and to avoid ionizing radiation. Quick diagnosis is still valuable for both an injured and healthcare professional. The efficiency of obtaining the answer to a focused question within minutes is one of the driving forces of the popularity of bedside ultrasound. Use of this modality in settings such as the emergency department can decrease waiting times and improve satisfaction among those served.[24]
Cardiac: Chest pain is one of the most common complaints presenting to the emergency department. Those presenting with chest pain, focused cardiac ultrasound can be helpful in the evaluation of persons with potentially life-threatening disease such as a pericardial effusion, a severe pulmonary embolus (or blood clot in the lungs), or in screening those with suspected aortic dissection.[11] The use of ultrasound is also helpful in persons with chest pain due to suspected heart ischemia, especially when the baseline electrocardiogram or EKG, is nondiagnostic.[11] The more technically demanding aspects of echocardiographic interpretation, and should be reserved for more formal comprehensive echocardiography.[11]
Abdominal complaints: Abdominal pain is also a common complaint in the primary care and emergency department setting. Gallbladder disease is a frequent cause of abdominal pain, but can also result in critical illness. Bedside ultrasound assesses the gallbladder for presence of gallstones that cause the majority of gallbladder illness. Emergency ultrasound of the gallbladder can help speed diagnosis and care.[25]
Flank pain can indicate obstructing kidney stones or abdominal aortic aneurysm.[26] If obstructing kidney stones are suspected, the kidneys can be evaluated by ultrasound for signs of obstruction, called hydronephrosis.[27][28] A common use of ultrasound is identifying or evaluating the fetus in a person who is pregnant. Women in the first trimester of pregnancy can have a tubal or ectopic pregnancy outside the uterus that is life-threatening if not identified.[29] A more advanced fetus may be evaluated for normal heart rate and movement and gestational age to help guide care of both the fetus and the pregnant mother.
Other symptom-oriented diagnostic exams: Blood clots that form in deep veins of the body can break off and block blood vessels in the lungs, resulting in low oxygen, heart strain and death. The most common location of these deep vein thromboses (DVTs) is in the legs. A bedside ultrasound can determine the presence or absence of blood clots and their location in the proximal lower extremity to behind the knee.[30][31] Those presenting with eye pain or visual loss, ultrasound of the eye can be used for the detection of orbital pathology.[32] Ultrasound has been described to detect retinal detachments, vitreous hemorrhage, dislocation of the lens, as well as evaluating optic nerve sheath diameters as a potential indicator of other diseases in the central nervous system.[33][34]
Now that ultrasound is available in portable units that are smaller than laptop computers and handheld models, it is being used more and more in many clinical settings. Many practitioners use point-of-care ultrasound in diagnosing other urgent and emergent problems, including appendicitis, testicular torsion, and abscesses. To describe each of these fully is beyond the scope of this entry, and impossible as the use of ultrasound is expanding rapidly:
Training[edit]
Emergency and point-of-care ultrasound is taught in a variety of settings. Many physicians are currently taught bedside ultrasound during the emergency medicine residency training programs in the United States. It can also be learned as part of the continuing education process, through formal didactics, one-on-one training, and clinical application and practice. Other specialists may learn during their residency or fellowship training programs. There are specialized fellowship training programs for bedside ultrasound in emergency medicine, but these are not required nor expected for the use of this tool in practice.References[edit]
作者: 心超 时间: 2013-12-19 09:18
标题: 心超版主推荐:Focused assessment with sonography for trauma
本帖最后由 心超 于 2013-12-19 10:26 编辑
回复 1# 心超
Focused assessment with sonography for traumaFrom Wikipedia, the free encyclopedia
"FAST scan" redirects here. For Fast-scan television, see Amateur television.
Focused assessment with sonography for trauma (commonly abbreviated as FAST) is a rapid bedside ultrasound examination performed by radiologists, surgeons, emergency physicians and certain paramedics as a screening test for blood around the heart (pericardial effusion) or abdominal organs (hemoperitoneum) after trauma.[1]
The four classic areas that are examined for free fluid are the perihepatic space (also called Morison's pouch or the hepatorenal recess), perisplenic space, pericardium, and the pelvis. With this technique it is possible to identify the presence of intraperitoneal or pericardial free fluid. In the context of traumatic injury, this fluid will usually be due to bleeding.
Contents [hide]
Extended FAST[edit]Further information: Radiographic findings in eFAST
The extended FAST (eFAST) allows for the examination of both lungs by adding bilateral anterior thoracic sonography to the FAST exam. This allows for the detection of a pneumothorax with the absence of normal ‘lung-sliding’ and ‘comet-tail’ artifact (seen on the ultrasound screen). Compared with supine chest radiography, with CT or clinical course as the gold standard, bedside sonography has superior sensitivity (49–99 versus 27–75%), similar specificity (95–100%), and can be performed in under a minute.[2] Several recent prospective studies have validated its use in the setting of trauma resuscitation, and have also shown that ultrasound can provide an accurate estimation of pneumothorax size.[3][4] Although radiography or CT scanning is generally feasible, immediate bedside detection of a pneumothorax confirms what are often ambiguous physical findings in unstable patients, and guides immediate chest decompression. In addition, in the patient undergoing positive-pressure ventilation, the detection of an otherwise ‘occult’ pneumothorax prior to CT scanning may hasten treatment and subsequently prevent development of a tension pneumothorax, a deadly complication if not treated immediately, and deterioration in the radiology suite (in the CT scanner).[5]
Advantages[edit]
A positive FAST - fluid (black stripe, indicated by red arrows) within Morison's pouch.
FAST is less invasive than diagnostic peritoneal lavage, involves no exposure to radiation and is cheaper compared to computed tomography, but achieves a similar accuracy.[6]
Numerous studies have shown FAST is useful in evaluating trauma patients.[7][8][9][10] It also appears to make emergency department care faster and better.[11][12] However, some authorities still have not accepted its use.[13]Interpretation[edit]
FAST Algorithm
FAST is most useful in trauma patients who are hemodynamically unstable. A positive FAST result is defined as the appearance of a dark ("anechoic") strip in the dependent areas of the peritoneum. In the right upper quadrant this typically appears in Morison's Pouch (between the liver and kidney). In the left upper quadrant, blood may collect anywhere around the spleen (perisplenic space). In the pelvis, blood generally pools behind the bladder (in the rectovesicular space or Pouch of Douglas). A positive result suggests hemoperitoneum; often CT scan will be performed if the patient is stable[14] or a laparotomy if unstable. In those with a negative FAST result, a search for extra-abdominal sources of bleeding may still need to be performed.[14]See also[edit] References[edit]
作者: aneshex 时间: 2013-12-20 20:08
存了下来,好好地学习一下,谢谢老师的分享
作者: 无形 时间: 2013-12-30 21:24
回复 1# 心超
谢谢分享,收藏细读。。
作者: cxbcxb 时间: 2014-2-16 19:24
合理应用这些切面可有效地监测术中的循环事件
作者: 暖暖2002 时间: 2014-5-28 15:55
很纠结,基层医院似乎离这个很遥远,学了也无法应用啊,远不如神经阻滞应用广泛啊
作者: 心超 时间: 2014-6-1 11:40
回复 13# 暖暖2002
循环监测和神经阻滞相比循环监测更为基础,麻醉安全是一切麻醉的基础!
作者: asaicu 时间: 2014-6-4 23:36
宋老师的认真认真,精益求精让人感动。华西2014可视化大会再次学习了。
作者: wanghe1110 时间: 2014-7-3 22:04
谁说麻醉医师不可以学超声啊,技术我有,天下无忧
作者: wwq55555 时间: 2014-7-24 15:12
现在国外RUSH检查流程已经非常成熟了,但好像国内急危重症没有怎么推广啊?
作者: 007 时间: 2016-4-14 15:22
这是一个短平快的办法!
作者: 仁心 时间: 2019-8-21 22:16
需要专用的心脏探头和TEE探头?
欢迎光临 新青年麻醉论坛 (http://xqnmz.com/)
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