61. Course Agenda
Introduction Abdominal Exam
Dr. Nitin Puri Orlando Debesa
5 min 20 min
Pre-test
Dr. Nitin Puri Practice on Models
10 min 30 min
Cardiology Exam Vascular Exam
Orlando Debesa Nitin Puri
20 min 10 min
Practice on Models Post-test
30 min 10 min
Pulmonary Exam
Nitin Puri Extra Practice ??
20 min 60 min
Practice on Models
30 min
Monologue: Welcome to Physics, the Abdomen and Spaghetti sauce. I thought it would be interesting to take a difficult area like physics and combine it with the abdominal lectures and show it together to facilitate conceptual learning. But first I want to tell you about a story I recently heard on TED talks by Malcolm Gladwell about Howard Mascowitts and the different varieties of spaghetti sauce. \nHe reinvented spaghetti sauce, 60s, short, thinning gray hair, has a parrot, loves the opera and medieval history. By profession he is a psychophyscists - measuring things. Went to Harvard. His first clients was PEPSI - we would like to make diet pepsi with aspertane and want you to figure out how much ASPERTANE to place and should be b/w 8-12% sweetness. We can do an experiment and plot it on a curve BUT when he does this the data is all over the place, its not a nice bell curve. So they made an educated guess of 10% but this is not good enough for Howard - it bothered him for years. One day sitting in a diner, it came to him - they were asking the wrong question, they should have been looking for the perfect pepsi(s) not the perfect pepsi. They thought he was crazy, no one would hire him. The PICKLE company came to him for what the perfect pickle is and he said there is no perfect pickle only perfect pickle(s), you need to make zesty not just improve the regular. Cambells made Prego and asked him to fix them. 45 varieties of tomatoes sauces he came up with and then grabbed a bunch of people and asked them to rate the 45 sauces. With all this data, he analyzed the data - not looking for the most popular BUT he grouped the data points into clusters; plain, spicey, and chunky were the three clusters the american people liked with extra chunky as the most popular. Chunky did not exist and once it was placed on their product line, they then made 600 million dollars the next years. Then 7 different mustards, olive oils and eventually Ragu jumped on board with 36 different ones. WHy is this important because he changed the way the food industry makes you happy - we were asking people what they wanted in their spaghetti sauces but no one for 36 years said they wanted the chunky one. People dont know what they want. We cant always explain what we want. Mustard does not exist on a hierarchy, only different ones that suit different people. We are obsessed with universals and the understanding of variability has become the latest thing (your cancer is different from mine). When you pursue a universal principle in food we are doing ourselves a massive disservice. When applying this story to ultrasonography, there is no universal way to learn this, there is lots of variability and finding your own variability is important. \n\nThis is Physics and the Abdomen and I have interlinked these two topics because much of what we see and dont see in the ultrasonographic abdomen has a “physical” explanation”\n
This is the Sonosite M-Turbo.\nProbably one of the most important things to know and add credibility to yourself in the eyes of others is to know where the “power” button is - this simple maneuver will set the tone among others especially if you don’t know where it is. \n
This is the Sonosite M-Turbo.\nProbably one of the most important things to know and add credibility to yourself in the eyes of others is to know where the “power” button is - this simple maneuver will set the tone among others especially if you don’t know where it is. \n
This is the Sonosite M-Turbo.\nProbably one of the most important things to know and add credibility to yourself in the eyes of others is to know where the “power” button is - this simple maneuver will set the tone among others especially if you don’t know where it is. \n
This is the Sonosite M-Turbo.\nProbably one of the most important things to know and add credibility to yourself in the eyes of others is to know where the “power” button is - this simple maneuver will set the tone among others especially if you don’t know where it is. \n
This is the Sonosite M-Turbo.\nProbably one of the most important things to know and add credibility to yourself in the eyes of others is to know where the “power” button is - this simple maneuver will set the tone among others especially if you don’t know where it is. \n
Phased Array Transducer (P17/P21 (1-MHz)\nCurved (Convex) Array Transducer (3.5 MHz transducer???)\nLinear Array Transducer (10 mhz or higher): vascular / tendons \n\n\nThe lower the # the MORE penetration BUT the less resolution of the image\n\nMention the indicator on the probe and the dot on the screen\n
Sound Propagation:\nIn everyday language, sound is an experience by the listener. Scientifically, sound is a phenomenon, not an experience, that is created by a vibrating mechanical disturbance traveling through a medium. \nAnalogous to the guitar, the US transducer emits pulses of sound wave that travel through a medium. \n\nAt the molecular level, when pressure is applied to tissue, these molecule are displaced and you get an alternating area of high pressures and low pressures\n\nWavelength is one of the important determinants of resolution in US. \n
Lower frequency = more penetration because the cycle length is longer and thus can penetrate deeper structures (good for larger people) but has less resolution (poorer image); curvilinear 4-5 MHz\nHigher frequency = less penetration because the cycle length is shorter and thus can not penetrate as well. Good for superficial structures and smaller people and has more resolution (better image).\nAmplitude: the maximum variation of a sound wave. Listeners perceive amplitude as loudness or volume. In ultrasound, it is referred to as output gain or acoustic power. \n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
Lets jump right in...In this example, there is a picture of the gallbladder. The transducer used for abdominal exams is the curved array transducer. As US pressure waves leave the transducer it will encounter a series of different mediums before the wave reaches the gallbladder. Ideally, as you encounter different mediums, the waves are reflected back to the transducer and an image is formed on your screen. \nBut of course, this not being an ideal world, things happen and not all these waves make it back home (to the transducer). Some of the waves get absorbed and others scatter and so there is a dimunition of the amplitude and a dampening of the wave. this is what we call ATTENUATION - it is a loss of sound strength and to the ultrasonographer could be the ENEMY or HERO.\n\n\n
For example, in this picture, the gallstone does NOT allow an image to appear behind it. So when US waves hit this stone and gets reflected back (does NOT penetrate the stone and thus leaves a SHADOW behind. This shadow helps us because it gives us an idea of what makes up “this object”. Examples of high-attenuation objects are gallstones or heavy calcified vessel walls. \n\n
Another cause of acoustic shadowing occurs when sound wave encounters a circular object (e.g.. round organs such as heart, kidney’s, or cystic structures such as the GB). When the US beam encounters a round corner the beam undergoes a change in velocity, gets deflected and never makes it back to the transducer thus producing a shadow. \n\nThis example allows us to review... rib calcifications cause a shadowing effect to be produced which can be utilized to identify the pleural line and thus notice if there is any sliding present during the identification of a pneumothorax. \n
- Depth gives you more or less PENETRATION\n- Adjust the depth so that the image of interest is in the middle of the screen\n- Space between depth marker is 1cm and is standard on all US units\n
In order to compensate for attenuation, the GAIN (or amplification) buttons can be used which are located on the left side of the keyboard. Traditional FAST exams do the cardiac views first to establish the overall GAIN based on the fluid inside the cardiac chambers. \nAgain, attenuation is the loss of strength of sound wave as it moves thru a medium. Increasing the GAIN increases the signal strength in the receiver and allows the image to appear brighter. Decreasing the gain makes the image appear DARKER. \nThere are three GAIN buttons:\n* Near field gain: controls the area nearest the transducer\n* far field gain: controls the area farthest from the transducer\n* overall gain: controls the entire image\n Before making any clinical judgements, the clinician should set the GAIN on the machine. Make sure your GAIN is adjusted so that the deeper structures, such as the liver or spleen are clearly visualized. \n\n\n\n
In order to compensate for attenuation, the GAIN (or amplification) buttons can be used which are located on the left side of the keyboard. Traditional FAST exams do the cardiac views first to establish the overall GAIN based on the fluid inside the cardiac chambers. \nAgain, attenuation is the loss of strength of sound wave as it moves thru a medium. Increasing the GAIN increases the signal strength in the receiver and allows the image to appear brighter. Decreasing the gain makes the image appear DARKER. \nThere are three GAIN buttons:\n* Near field gain: controls the area nearest the transducer\n* far field gain: controls the area farthest from the transducer\n* overall gain: controls the entire image\n Before making any clinical judgements, the clinician should set the GAIN on the machine. Make sure your GAIN is adjusted so that the deeper structures, such as the liver or spleen are clearly visualized. \n\n\n\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
The EASIEST abdominal view to obtain is the view of Morison’s pouch. Simply place the transducer with the indicator notch pointed toward the head at the mid-axillary line at about the 8th to 11th intercostal space. \nIf having difficulty visualizing the liver-kidney interface, you can always follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
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Anechoic free fluid may be fresh blood or ascites related to:\n- P->primary liver failure\n- R->right-sided heart failure\n- A->aggressive fluid resuscitation with capillary leak\n- P->portal HTN\n\nThis next picture shows the presence of echogenicity within the fluid suggesting its an exudate which could represent hemoperitoneum with organized clots or peritonitis with an infectious etiology which usually has septations or loculations that may not be appreciated on CT scan. \n\n
Impedance is the molecular property intrinsic to different types of mediums. Here you can see the hyperechoic diaphragm. Because of its high impedance, sound does not travel through it as readily and bounces back to the transducer thus giving it its hyperechoic look (if the sound did not travel through it at all, then you would see acoustic shadow). However, some sound waves do penetrate through BUT become angled. Not knowing, the US system assumes that the sound continues to travel in a straight line and places the image deeper (this is because the time it takes for the sound wave to make it back to the transducer has to be taken into account). The reflected new image that is created is always placed deeper because the redirected beam will take longer to reach the transducer.\nSo, as sound traveling through one medium encounters a second medium with a different impedance, the sound wave undergoes reflection or scattering which produces the mirror image of the liver within the thoracic cavity. \nThis phenomenon can be used to rule-out pleural effusions. \n\n\n \n\n
- position: supine or left lateral decubitus (depends on if unable to get good view)\n- use abdominal probe or curvilear probe\n- longitudinal position in RUQ or Morrison’s view (hepatorenal view from FAST exam)\n- The marker aimed cephalic\n- have patient inhale to bring the GB into view as the diaphragm depresses the liver (you might need to move the probe up in the intercoastal position at 7-8th rib space with the marker pointing toward the axilla - the liver used as an acoustic window to avoid bowel gas)\n\nUS has >95% accuracy for diagnosing gallstones\n
Acoustic enhancement is when ultrasound passes through area of lower attenuation causing structures located beneath to appear hyperechoic. This type of artifact is useful to differentiate cysts from cystic tumors or abscess that have higher attenuation and will not produce this artifact. \n\nEvery GB has this thing called the junctional fold and you should look for it to make sure its the GB and not fluid collection. \n
- finding sludge in the GB is common although nonspecific\nTypical sludge is:\n- homogenous echos\n- due to bile stasis\n- moves slowly \n- does NOT SHADOW (if does consider Milk of Calcium)\n- typical sludge has FLUID/DEBRI LEVEL (if ROUNDED, think hemobilia)\nHemobilia can be large a resemble a mass BUT does NOT distort the GB wall like GB cancer does because it is so aggressive and breaks through the GB wall. \n\nUse the highest frequency possible to make a diagnosis\nAlso if scanning, becareful with artifacts created by the duodenum mimicking “stuff” inside the GB\n
- Gallstones appear hyperechoic structures with significant SHADOWING.\n- having the patient switch positions will prove to you that the GALLSTONE is not impacted\n- sometimes structures in the GB neck that casts a shadow needs to be evaluated (e.g. bowel gas, stone, valve??)\n
US Criteria for acute cholecystitis:\n1) cholelithiasis - major criteria\n2) focal GB tenderness - major criteria\n3) GB size and shape: >4mm thickened anterior wall; Transverse diameter > 5cm\n4) GB wall changes (diffuse vs focally thick) see DDx below\n5) pericholecystic fluid collections\n6) intraluminal changes\n\n- Cholecyctitis findings: \n1) >4mm thickened anterior wall\n2) - Pericholic cystic fuid\n- and / or -\n3) Transverse diameter > 5cm\n\nDiffuse Wall Thickening is a nonspecific sign noted in MANY different pathologic states\n- acute/chronic cholecystitis\n- patient not fasting\n- chronic hypoalbuminemia\n- hepatitis\n- CHF\n- cholangitis (AIDS)\nFocal GB wall thickening\n- C->cholangitis (AIDS)\n- A->adenomyomatosis (also has intramural cysts by the fundus and comet tail artifacts caused by reverberations of crystals stuck in the cysts and Rogutensky sinuses)\n- G->gangrenous cholecystitis\n- A->adenomas\n- M->metastases\n- C->carcinoma\n- P->polyps\n\nWhen scanning the GB, it is very important to see the GB neck, which is located in the interlobar fissure and the fundus. \n
This is maximal pain elicited over the sonographically localized gallbladder. Negative if there is no pain or diffuse pain. This test is 86% SENSITIVE. The specificity was 35%\n
In this study, Kendal and Shrimp reported only a 45% sensitivity when done by radiologist compared to 75% when done by ED. The proposed difference was that the radiologist were using hard copies and not performing the test. \nRecommendation: just repeat the study (the beauty of US)\n
The fluid may also be due to a perforation of the GB, which commonly occurs at the fundus, because of its poor blood supply tends to suffer first. \n\nWall changes \n- irregularly thick fundic involvement\nIntraluminal changes that suggest the mucous is sloughing in association with gangrene\n- membrane-like strands\n- sludge\nPericholecystic changes \n- pericholecystic fluid (from abscess) or air\n
Often very difficult to diagnose because there are usually other illnesses. There are no stones, too sick to localize pain over GB and once there is perforation/gangrene you lose the US Murphys sign. So biliary aspiration done if suspected. One thing you could look for is inflammation around the GB (dirty inflamed fat). \n
- follow GB toward the neck\n- rotate the probe until transverse view of “mickey mouse” face (portal triad=hep artery, portal vv, bile duct)\n- large circle - portal vein\n- 9 oclock - hepatic artery\n- 3 oclock - CBD\n- Bottom longitudinal: portal vein (bigger) and CBD on top of it\n- even bigger vessel is the IVC\n- you can always use color doppler to help identify vessels\n
- follow GB toward the neck\n- rotate the probe until transverse view of “mickey mouse” face (portal triad=hep artery, portal vv, bile duct)\n- large circle - portal vein\n- 9 oclock - hepatic artery\n- 3 oclock - CBD\n- Bottom longitudinal: portal vein (bigger) and CBD on top of it\n- you can always use color doppler to help identify vessels\n
- a CBD > 0.6cm is indicative of obstruction (note if the patient has a had biliary manipulation, such as ERCP, duct size is not indicative of pathology)\n
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The spleen is a homogenous, echogenic structure that sits in the LUQ. It has less visible vessels when compared to the liver because its architecture is made up of red and white pulps. Wandering (floating/ectopic) spleen is one that can move about its hilar stock. Splenomegaly = >13cm x 6cm or if longer than adjacent left kidney. To view the spleen place the probe along the Left Coronal and Intercostal Oblique Views (posterior-axillary line at about the 6th to 9th intercostal space with the marker-dot pointed cephalic). This is often the most difficult abdominal view to obtain.&#xA0; \nAccessory spleen are round smooth isoechoic nodules < 3cm in diameter that occurs developmental. They are seen in 10% of patients and are more common in splenomegaly. \n\n- To get rid of rib shadows, and to get a better view of the spleen, slide the probe cephalad and rotate it very slightly clockwise, producing an intercostal oblique view, so that the spleen (not the kidney) is seen \n
Free fluid is RARELY seen between the spleen and the kidney but rather surrounding all other parts of the spleen or between spleen and diaphragm.&#xA0; \n
- The goal of bedside renal ultrasonography is to rapidly evaluate the patient presenting to the ED with flank pain, abdominal pain with hematuria or decreased urinary output to answer a few basic questions:\n&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; Is there hydronephrosis?&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; Unilateral or bilateral?&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; Is there fluid around the kidney?&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; &#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; Is the bladder distended?&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; Are stones seen?&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0;&#xA0; Is the aorta normal\n- The disadvantages of emergency renal ultrasonography are that it does not assess renal function (as IVP does) and it cannot typically identify/size the ureteral stone.\n
- On longitudinal view, the kidney will appear football-shaped and will typically be 9-12 cm in length and 4-5 cm in width (normally within 2 cm of each other)\nRenal sinus is in the middle\nRenal parenchyma is on the outside. \n\nThe normal kidney will have a bright area surrounding it which is made up of Gerota&#x2019;s fascia and perinephric fat.&#xA0; The periphery of the kidney will appear grainy gray which is made up of the renal cortex and pyramids.&#xA0; Sometimes you can see the individual pyramids, but this is not always the case.&#xA0; The central area of the kidney, the renal sinus, will appear bright (echogenic) and consists of the calyces, renal pelvis and the renal sinus fat.&#xA0; Always scan both kidneys for comparison and correlation to clinical picture.&#xA0; The ureters are generally not well visualized by ultrasound, but, when distended may appear as a tubular structure extending inferiorly from the kidney\n
- On transverse view, the kidney appears C-shaped\n-\n
- Color Doppler shows hilum vessels in red and blue\n
- There are many normal variations in the anatomic structure of the kidneys.&#xA0; Some common ones that you may identify include:&#xA0; Double collecting system, where the renal sinus is divided by a hypertrophied column of Bertin; horseshoe kidney, where the left and right kidney are connected to each other, usually at the lower pole; Renal ectopia, where one or both kidneys are outside the normal renal fossa\n
The alternative imaging studies that are used to diagnose acute renal colic include IVP and spiral CT scan.&#xA0; In IVP, intravenous contrast is injected and a series of plain abdominal radiographs are obtained.&#xA0; The intravenous contrast agent is filtered by the kidney and appears bright white on the radiographs.&#xA0; The radiographs are reviewed to evaluate for a delay in renal filtering of the intravenous contrast agent and for evidence of hydronephrosis as the contrast is filtered.&#xA0; A delay in filtering of the intravenous contrast along with the presence of hydronephrosis indicates obstruction.&#xA0; With high resolution spiral CT, images are obtained from the kidney to the bladder without the use of IV contrast.&#xA0; This allows the reader to view serial cross sectional images of the kidney and ureter to identify hydronephrosis.&#xA0; In comparison to ultrasound or IVP, CT scan can routinely identify ureteral stones and provide accurate measurements of the stone&#x2019;s size.&#xA0; Just remember, no study can identify hydronephrosis or ureteral calculi 100% of the time\n
- Dilated ureter seen below bladder (transverse view)\n
- The underhydrated patient may not have hydronephrosis on initial renal scanning, despite the presence of obstruction and renal colic&#xA0;\n
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- Kidney with severe hydronephrosis.&#xA0; Note that the shape of the kidney is completely obliterated by the severe hydronephrosis\n
- Renal cysts can sometimes be mistaken for hydronephrosis.&#xA0; Cysts are typically single and arise in the periphery of the kidney, but can be multiple as in polycystic kidney disease.&#xA0;\n
- Remember, the patient with multiple renal cysts may also have liver cysts.&#xA0; Perform a quick ultrasound of the liver to screen for liver cysts in these patients.&#xA0; Additionally, certain forms of polycystic kidney disease are associated with intracerebral aneurysms; followup is important in these patients.\n
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- Pelvic views are not as easy to obtain as right upper quadrant views, but since the pelvis is the most dependent part of the peritoneal space, it is the most likely place to see abdominal free fluid. &#xA0;\n- It is a good idea to obtain both longitudinal and transverse views of the pelvis. \n- If the longitudinal view is performed first, it is often easier to understand the anatomy and obtain good images.&#xA0; \n- Place the probe in the midline just cephalad to the pubic bone with the marker-dot pointed cephalad.\n- In the male US above, free fluid will be seen along the intraperitoneal portion of the posterior to the wall of the bladder\n\n\n
- Make sure the probe position is correct by actually placing the probe on the pubic bone and noting a bone shadow on the image.&#xA0; \n- From this position sliding the probe slightly cephalad will produce a good longitudinal pelvic view.&#xA0; The bladder will be found just cephalad to the pubic bone, and can usually be found even if it is nearly empty.&#xA0; A full bladder will be triangular in shape.&#xA0; \n- The lower angle of the bladder marks the border between the intraperitoneal space (left side of the image) and the true pelvic structures (right side of the image).\n- In a male, free fluid will be seen along the intraperitoneal portion of the posterior to the wall of the bladder. If the bladder is empty, it is very difficult to recognize pelvic free fluid in a male\n
- In a female, the body of the uterus sits in the intraperitoneal space just posterior to the bladder, so free fluid will be seen just posterior to the uterus.&#xA0; This space is often called the pouch of Douglas and sometimes just small amounts can be detected.\n- Free fluid may also be seen completely surrounding the edges of the uterus.&#xA0; If the bladder is empty, it is very difficult to recognize pelvic free fluid in a male.&#xA0; In a female, the pouch of Douglas may still be identifiable, even when the bladder is empty.\n
- To obtain transverse views, simply rotate the probe 90 degrees, pointing the probe marker to the patients' right side.&#xA0; \n- In transverse pelvic views, free fluid may be seen posterior to the bladder or uterus, or adjacent to the corners of the full bladder.\n
- Small amount of free fluid posterior to the bladder.\n
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- when we look at the abdomen, there are 3 areas to focus on\n- from a trauma point of view, I&#x2019;m looking for blood; from a non-traumatic point of view I&#x2019;m looking for fluid (ascites possibly as a reason responsible for their hypotension)\n
- Good afternoon, and thank you for coming.\n- I know your really excited about this\n- Today we have made it easier for you to save your patients life in a very rapid & efficient way\n
- from the previous 2 lectures, you have been given the arsenal of how to diagnose and treat cardiac and pulmonary conditions \n
- But let us take a step back, and ask ourselves WHAT the sole purpose of WHY bedside US is important in the first place... \n- What is the question(s) we are looking to answer\n- Many times the answer is SHOCK!!!\n\n
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- Shock is one of the most CHALLENGING issues in Critical Care\n- even the most SEASONED physician, standing at the BEDSIDE of the patient in extremis, can be unclear about the cause of shock and the optimal initial therapeutic approach\n- traditional (Mn: Pizza Hut logo) PHYSICAL EXAM techniques can be misleading (Jones, Critical Care 2004)\n- patient in shock have high MORTALITY (skull) rate which can be correlated to the amount and DURATION of hypotension\n- So diagnosis and initial care must be accurate and prompt to optimize patient outcomes (Jones, Shock 2004)\n\n
- The American College of Emergency Physicians has new guidelines that further delineate a new category of &#x201C;RESUSCITATIVE ultrasonography&#x201D;\n- studies have shown that the INITIAL (#1) integration of BEDSIDE ULTRASONOGRAPHY into the evaluation of patients with shock results in more ACCURATE initial diagnosis and IMPROVED patient care plan (Pershad, Pediatrics 2004) \n
- Physical findings often OVERLAP between the categories and their subtypes often making it difficult to assess clinically which classification of shock best fits the patient\n- e.g.. cardiogenic shock, tamponade and sepsis (with myocardial depression) may all present with DISTENDED NECK VEINS and respiratory distress. \n- Swan-Ganz was great (lots of detail) but larges studies have demonstrated no improvement in mortality (Shah, JAMA 2005)\n
- the first and most crucial part in the evaluation of the patient in shock is determination of the cardiac status. \n- the ECHO is limited and focuses on 3 areas:\n1) pericardial sac\n2) left ventricle global contractility\n3) right ventricle size compared to the left\n
- 60% of hypotensive events are of cardiac origin\n
- 60% of hypotensive events are of cardiac origin\n
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- angle the probe to the right to see the IVC\n- the marker dot is pointing cephalad\n- response of the IVC to sniff indicates central venous pressure\n- no collapse\n* CHF\n* Tamponed\n* PE\n* Pneumothorax\n
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- M-mode: shows motion of an area plotted against time in a still frame (mainly used for cardiac exams)\n- A reliable assessment of volume status in the haemodynamically unstable patient is valuable in guiding management. Many a times, a more crucial question to answer is whether, the patient will respond to a bolus of fluids by raising his cardiac output, blood pressure or both\n- place a M-mode line through the IVC 1-2cms from its junction with the right atrium, and obtain a M-mode tracing\n- If the patient is spontaneously breathing, ask him to take a short quick inspiratory effort ("a sniff") during the M-mode recording. If the patient is mechanically ventilated, record the M-mode through 3 or 4 respiratory cycles.\nFreeze the M-mode image and using calipers, measure the maximum and minimum diameter of the IVC tracing.\n- Low CVP is increasingly is likely as IVC diameter (IVCD) gets smaller than 1 cm and abnormally high CVP increasingly likely as IVCD increases above 2cm. However, there is wide variation and the absolute measurements are not applicable with positive pressure ventilation.\n
- In a patient requiring VENTILATORY support, the inspiratory phase induces an increase in pleural pressure, which is transmitted to the right atrium, thus REDUCING Venous Return. The result is an inversion of the cyclic changes in IVC diameter, leading to increases in the inspiratory phase and decreases in the expiratory phase.\n- In mechanically ventilated patients, a 12% or more variation identified patients likely to respond to vascular filling, in terms of increased cardiac output, from those who would not respond, with a positive predictive value of 93% and a negative predictive value of 92%. It must be remembered that the measurements should be taken during mandatory ventilator breaths and the tidal volume should be at least 8 ml/kg.\n
- IVC with variability and NO variability\n- a small caliber IVC (<2cm diameter) with an inspiratory collapse greater than 50% roughly correlates to a CVP <10cm of water\n
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Evaluating:\n- evaluate fluid in pericardium\n- (R) heart strain\n- septal bowing\nTech Problems:\n- body habitus\n- inability to get probe under xiphoid\n
- normal anatomy\n- liver at the top of the screen\n
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- the fluid is usually dark or anechoic within the pericardial space\n\nQ: Where do you measure amount of fluid\nA: anteriorly between the heart and liver\n
- (R) ventricular collapse during diastole\n
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- isolated small anterior anechoic areas on the parasternal long axis view often represent a pericardial fat pad, as free flowing pericardial effusions will tend to layer posteriorly and inferiorly with gravity\n
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- Motion of anterior leaflet of the mitral valve can also be used to assess contractility. \n- In a normal contractile state, the anterior leaflet will vigorously touch the wall of the septum during ventricular filling when examined using the parasternal long-axis view.\n
- Moving the probe into the parasternal short-axis orientation will give confirmatory data on the strength of contractions.\n- In this view, a left ventricle with good contraction will appear as a muscular ring that squeezes down concentrically during systole. \n- Whereas cardiologists often use the parasternal short-axis view to evaluate for segmental wall motion abnormalities, this is a more subjective measurement, and determinations may differ among different clinicians. \n- For that reason, it is better for the EP to initially concentrate on the overall contractility of the ventricle, rather than to evaluate for segmental wall motion deficits\n
- The optimal cardiac views for determining this ratio of size between the 2 ventricles are the parasternal long and short-axis views and the apical 4- chamber view. \n- The subxiphoid view can be used, but care must be taken to fan through the entire right ventricle, as it is easy to underestimate the true right ventricular size in this view.\n
- assesses how full the tank is\n
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- hepatization: when the pleural effusion exerts compression of the lung and makes it look like the liver\n- Hemothorax sensitivity: 92%\n- Hemothorax specificity: 100%\n
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- Comet tail artifact is a form of reverberation echo that arises from irregularity of the lung surface. This phenomenon appears as a vertical echoic line originating from the pleural line and extending down into the lung tissue. The presence of comet tail artifact rules out a pneumothorax.The combination of a lack of lung sliding and absent comet tail artifacts strongly suggests pneumothorax.\n
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- when we look at the abdomen, there are 3 areas to focus on\n- from a trauma point of view, I&#x2019;m looking for BLOOD; from a non-traumatic point of view I&#x2019;m looking for FLUID (ascites possibly as a reason responsible for their hypotension)\n- the FAST exam can detect fluid as little as 100cc (more commonly 250-620cc)\n- FAST Exam Sensitivity: 79%- FAST EXAM Specificity: 99%\n
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- Right Coronal and Intercostal Oblique Views: The easiest abdominal view to obtain is the view of Morison&#x2019;s pouch.&#xA0; \n- located in the mid-axillary line at about the 8th to 11th intercostal space with the marker-dot pointed cephalad (this gives a coronal view of the interface between the liver and kidney). &#xA0;\n- It is important to follow the lower edge of the liver caudally until a good view of the tip is obtained.\n
- Free fluid is usually seen in Morison&#x2019;s pouch or along the lower edge of the liver and around the lower tip of the liver. \n- Rib shadows may be prominent when the marker-dot is pointed directly cephalad.&#xA0; Shadows can be minimized by rotating the probe very slightly counter-clockwise, so the marker-dot is pointed toward the posterior axilla and giving an intercostal oblique view.\n
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- Left Coronal and Intercostal Oblique Views: This is often the most difficult abdominal view to obtain.&#xA0; \n- Place the probe in the posterior-axillary line at about the 6th to 9th intercostal space with the marker-dot pointed cephalad, producing a coronal view.&#xA0; From this position the interface between the spleen and left kidney can be found.&#xA0; Free fluid is rarely seen between the spleen and the kidney but rather surrounding all other parts of the spleen or between spleen and diaphragm.&#xA0; \n- To get rid of rib shadows, and to get a better view of the spleen, slide the probe cephalad and rotate it very slightly clockwise, producing an intercostal oblique view, so that the spleen (not the kidney) is seen \n
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- Position: supine\n- Curvilear transducer\n- epigastric approach at xiphoid level\n- ask pt take a deep breath and hold it to improve the acoustic window\n\nAxial ultrasound image showing pancreatitis. The pancreas (P) is draped over the splenic vein (SV), which is hypoechoic and swollen, with a rim of fluid around its edge (white arrows). A is the aorta and IVC the inferior vena cava\n
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- Pelvic views are not as easy to obtain as right upper quadrant views, but since the pelvis is the most dependent part of the peritoneal space, it is the most likely place to see abdominal free fluid. &#xA0;\n- It is a good idea to obtain both longitudinal and transverse views of the pelvis. \n- If the longitudinal view is performed first, it is often easier to understand the anatomy and obtain good images.&#xA0; \n- Place the probe in the midline just cephalad to the pubic bone with the marker-dot pointed cephalad.\n- In the male US above, free fluid will be seen along the intraperitoneal portion of the posterior to the wall of the bladder\n\n\n
- Make sure the probe position is correct by actually placing the probe on the pubic bone and noting a bone shadow on the image.&#xA0; \n- From this position sliding the probe slightly cephalad will produce a good longitudinal pelvic view.&#xA0; The bladder will be found just cephalad to the pubic bone, and can usually be found even if it is nearly empty.&#xA0; A full bladder will be triangular in shape.&#xA0; \n- The lower angle of the bladder marks the border between the intraperitoneal space (left side of the image) and the true pelvic structures (right side of the image).\n- In a male, free fluid will be seen along the intraperitoneal portion of the posterior to the wall of the bladder. If the bladder is empty, it is very difficult to recognize pelvic free fluid in a male\n
- In a female, the body of the uterus sits in the intraperitoneal space just posterior to the bladder, so free fluid will be seen just posterior to the uterus.&#xA0; This space is often called the pouch of Douglas and sometimes just small amounts can be detected.\n- Free fluid may also be seen completely surrounding the edges of the uterus.&#xA0; If the bladder is empty, it is very difficult to recognize pelvic free fluid in a male.&#xA0; In a female, the pouch of Douglas may still be identifiable, even when the bladder is empty.\n
- To obtain transverse views, simply rotate the probe 90 degrees, pointing the probe marker to the patients' right side.&#xA0; \n- In transverse pelvic views, free fluid may be seen posterior to the bladder or uterus, or adjacent to the corners of the full bladder.\n
- Small amount of free fluid posterior to the bladder.\n
- Be sure to scan the aorta for AAA in the patient who clinically appears to have acute renal colic, but in whom the renal scanning is normal.\n- A transverse image of the aorta shows a classic example of the seagull sign.&#xA0;&#xA0; The celiac trunk branches into the hepatic (H) and splenic (S) arteries.&#xA0; The inferior vena cava (IVC) is seen to the left of the aorta\n
- Transverse image of the normal proximal aorta (A) shown in its relationship to the vertebral body (arrow).&#xA0; IVC = inferior vena cava; H = hepatic artery; L= liver.\n
Longitudinal view of the normal proximal aorta showing the branches of the celiac artery and SMA.&#xA0; SMA = superior mesenteric artery; VB = vertebral body.\n
- Transverse image of the normal mid to distal aorta (A) and inferior vena cava (IVC) before the bifurcation into the iliac arteries.&#xA0; The vertebral body (arrow) causes a characteristic shadowing artifact.&#xA0;\n
- Longitudinal-oblique view of a normal lower aorta and bifurcation\n
- AAA is diagnosed when the diameter exceeds 3.0 cm.\n- It has been demonstrated that the risk of rupture for an AAA of 3.0 cm is less than 4% over 5 years; this risk, however, substantially increases for AAA&#x2019;s with larger diameters\n
- Transverse image of an AAA with an intraluminal thrombus.&#xA0; This figure demonstrates the importance of measuring the aorta from the outer walls.&#xA0;\n- Obtain measurements of the aorta from outer wall to outer wall.&#xA0; Since aneurysms will often contain a thrombus, one may accidentally mistake the inner rim of the thrombus for the aortic wall.&#xA0; Doing this will lead a falsely decreased measurement \nof the true aortic diameter.\n
- these 2 diagnoses should not be overlooked in women of childbearing age that present with hemorrhage in the abdomen. \n- AAA may occasionally rupture into the peritoneal cavity\n
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Sonosite M-Turbo\n- Understand what the main buttons do\n- Gain: compensates for attenuation (loss of strength of sound wave as it moves thru a medium)\n* Near field gain: controls the area nearest the transducer\n* far field gain: controls the area farthest from the transducer\n* overall gain: controls the entire image\n- Depth: controls penetration; goal is to have the area of interest in the middle of the screen\nMODE KEYS:\n- 2D: the standard black and white US image (aka B-mode)\n- M-mode: shows motion of an area plotted against time in a still frame (mainly used for cardiac exams)\n- color: shows the DIRECTION of blood flow\n- doppler: measures the SPEED of blood flow through an area. \n\n
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Wall is first line, the stone filling the GB is the second line and a little bit of bile b/w these two layers. \nIn the 2nd picture, is from a pt with no GB with air in the stomach which mimics WES sign. \nIf a single line, consider a porcelain GB and remove it because of its association with GB cancer (they are also associated with having stones). GB cancer is usually very aggressive and distorts the GB wall. \n
Put this in the lung section\nReverberation occurs when sound encounters two highly reflective layers.&#xA0; The sound is bounced back and forth between the two layers before traveling back.&#xA0; The probe will detect a prolonged traveling time and assume a longer traveling distance and display additional &#x2018;reverberated&#x2019; images in a deeper tissue layer (Figure 9).\n
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- The most important mode for the ultrasound-beginner is the B-mode.&#xA0; B-mode stands for &#x2018;brightness mode&#x2019; and provides structural information utilizing different shades of gray (or different &#x2018;brightness&#x2019;) in a two-dimensional image (Figure 1).\n
- M-mode stands for &#x2018;motion mode&#x2019;.&#xA0; It captures returning echoes in only one line of the B-mode image but displays them over a time axis.&#xA0; Movement of structures positioned in that line can now be visualized.&#xA0; Often M-mode and B-mode are displayed together on the ultrasound monitor. (Figure 2)\n- M-Mode (lower portion of the image) combined with B-Mode image.&#xA0; In this still image the M-mode captures the movement of a particular part of the heart.\n
The Doppler mode follows very sophisticated and complex laws of physics.It utilizes a phenomenon called &#x2018;Doppler shift&#x2019;, which is a change in frequency from the sent to the returning sound wave.&#xA0; These changes or &#x2018;shifts&#x2019; are generated by sound waves reaching moving particles.&#xA0; The change of frequency/amount of shift correlates with the velocity and direction of particle motion.In simplified terms, the Doppler mode examines the characteristics of direction and speed of tissue motion and blood flow and presents it in audible, color or spectral displays.\nColor Doppler ultrasound is also called 'color-flow ultrasound'.&#xA0; It is able to show blood flow or tissue motion in a selected two-dimensional area.&#xA0; Direction and velocity of tissue motion and blood flow are color coded and superimposed on the corresponding B-mode image (Figure 3).\n
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- probe 2cm superior to pubic symphysis\n- midline of abdomen\nEvaluating:\n- free fluid in pelvic cul-de-sac (Pouch of Douglas)\n- bladder\n- uterus: usually superior to bladder\n- prostate: usually posterior to bladder\nTechnical Problems:\n- body habitus\n- empty bladder (no landmarks)\n
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- probe 2cm superior to pubic symphysis\n- midline of abdomen\nEvaluating:\n- free fluid in pelvic cul-de-sac (Pouch of Douglas)\n- bladder\n- uterus: usually superior to bladder\n- prostate: usually posterior to bladder\nTechnical Problems:\n- body habitus\n- empty bladder (no landmarks)\n
