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88 Cards in this Set
- Front
- Back
what is the definition of ultrasound
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energy generated by sound waves of 20,000 or more vibrations per sec
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medical ultrasound is what
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sound waves in the 2-12 million cycles per second (MHz) range which are produced and detected by transducers contained in a hand-held probe
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with ultrasound the tranducer is what and does what
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*is piezoelectric crystals
*change electrical voltage into sound waves and reflected sound waves back into voltage |
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the image seen on the screen with ultrasound is made up of what
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many individual scan-lines
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with ultrasound the scan-lines seen on the screen each scan-line is made from what
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the transmitted and received ultrasound pulse from one set of crystals
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tissue penetration or the depth to which sound waves produced by the transducer will travel and reflect largely depends on what
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upon the frequency range of the transducer
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superficial structures with ultrasound are how deep
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0-3 cms
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superficial structures with ultrasound require what kind of transducer frequencies
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HIGH
-6-12 MHz |
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what is an example of a superficial structure with ultrasound
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interscalene
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deeper structures with ultrasound are how deep
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4-8 cms
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deeper structures with ultrasound require what kind of transducer frequencies
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LOWER
-2-4 MHz |
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what is an example of a deeper structure with ultrasound
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SCIATIC
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the denser or more rigid the layer encoutered with US the lesser or greater the amt of wave that will be reflected
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GREATER
(example BONE) |
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bone is an example of what kind of waveform on ultrasound
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HYPERECHOIC
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the less dense or less rigid the layer encountered on US the less or greater the wave will be reflected
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LESS
(example VESSELS) |
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the lack of a reflected wave leaves what on the US screen
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a blackened area
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a vessel is an example of what on the US screen
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HYPERECHOIC
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the side of the US probe that has the perpendicular lines should be oriented how
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to the PATIENTS right
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the most common way to view a target nerve is to hold the probe how
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at a RIGHT angle to the long axis of the nerve (transverse view)
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what is an out of plane approach
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if the needle is directed perpendicular to the long axis of the probe
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with US what is the longitudinal view
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the longitudinal edge of the probe is held facing the long axis of the nerve
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with US what is the most difficult view for needle placement since it is difficult to hold probe centered
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longitudinal view
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with US what is an in plane approach
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if the needle is introduced parallel to the long axis of the probe
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with US what view is a good view to appreciate anatomy and distribution of LA AFTER it has been placed
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in plane approach
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what is toggle
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making changes to the angle at which the tranducing probe is held to the body surface can result in very diff images being produced
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with central line placement US allows you to differentiate b/t what structures
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IJ and carotid artery
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what is the IJ like with US when placing a central line
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it can be compressed with the probe and will usually distend when pt placed in trendelenburg
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what is the carotid artery like with US when placing a central line
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it pulsates and will NOT compress with pressure
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with central line placement US allows you to view overlap of what structures
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IJ and carotid artery
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why are pts placed in trendelenburg for central line placement
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to decrease risk for air emboli
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what are the advantages for using US for blocks/line placement
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*procedures are done under direct vision (#1)
*allows for respositioningof the needle after injection *LA placement in relation to nerve location is seen immediately *lower volumes of LA can be used d/t more accurate placement around the nerve |
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an interscalene block produces what kind of block
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a dense, solid brachial plexus block
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an interscalene block is best suited for what kind of procedures
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procedures of the shoulder and upper arm
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the interscalene is relatively easy to locate where
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within the brachial plexus sheath b/t the middle and anterior scalene muscles
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what is the pt positioning for an US for an interscalene block
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*supine or head slighly elevated
*both arms at side *head turned away from side being blocked *US screen should be opposite from the blocker |
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when scanning with the US for a interscalene block start out by locating what
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the brachial plexus in the supraclavicular space and follow it back to the interscalene space
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when scanning with US for an interscalene block after identifying the subclavian artery where in relation to the artery is the brachial plexus
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on the postero-lateral side of the artery--they are a group of smaller circles bunched together
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when performing an interscalene block under US tech how do you know that you are passing b/t the ant and middle scalene muscles
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while tracing the nerves back up the neck you will notice that they line up in a vertical column that indicates that you are passing thru the ant and middle scalene
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what needle approach with US interscalene is less discomfort and avoids the jugular veins and carotid
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IN-PLANE tech
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with an interscalene US tech you want to keep the needle where
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b/t the scalene muscles and within the brachial plexus sheath
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when doing an interscalene with US if the injection goes into the scalene muscle what should be done
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stop injecting and redirect the needle between the muscles again
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when performing an interscalene block with US what are some tips to help AVOID a phrenic nerve block
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*approch brachial plexus at a lower point
*use less LA volume (6mls) *use a lower concentration of LA-may not be sufficient for sx motor block but works well for post-op pain control |
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an axillary block with US produces what kind of block with what kind of onset
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*DENSE block
*RAPID onset |
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an axillary block with US is suitable for what kind of procedures
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*forearm
*hand |
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what is the disadvantage of axillary block with US
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requires the repositioning of the needle min 3 times to provide coverage of the nerve targets
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what is the pt positioning for an axillary block with US
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*supine
*arm should be ABducted with elbow flexed and hand near head *positon yourself facing axilla |
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when scanning for axiallary block with US hold the probe how
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transverse to the long axis of the brachial plexus
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when scanning for axillary block with US you should place the probe where
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over the axillary artery high on the upper arm close to the junction with the shoulder
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when scanning for axillary block with US what should you maintain in the center of the pic
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axillary artery
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when scanning for axillary block with US the nerves of the brachial plexus will appear much brighter (hyperechoic) where
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in the axilla
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for in plane needle approach for an axillary block with US the needle should be directed from where
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the top side
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for an out of plane needle approach for an axillary block with US what is done
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this approach uses 1 cm long skin wheal parallel to the probe to change entry points
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a femoral block with US is a reliable block for post-op pain relief for what procedures
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*ANTERIOR thigh and knee
*MEDIAL portion of lower leg |
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a femoral block using US is for pain relief for pain involving what structures
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POSTERIOR portion of
*upper leg *knee *lower leg |
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a femoral block using US is commonly combined with what other block
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SCIATIC block
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what is the positioning for a femoral block using US
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*supine
*stand along side upper thigh *US machine should be opposite your position |
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with a femoral block with US what should scanning depth be set at
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4-5 cms
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with a femoral block with US what artery do you want to locate
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FEMORAL
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with femoral block with US you want to stay above where with the femoral artery
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the bifurcation
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when performing a femoral block with US the space containing the femoral nerves will resemble what
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a triangular shape
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what are the injections needed for a femoral block with US
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3 SEPARATE injections
*just lateral to femoral art *at the angle below the artery *at the lateral tip of triangle |
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the sciatic nerve blocked in the popliteal area will provide post-op pain control for sx where
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of the lower leg and foot
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what is the exception to pain control provided by block of the sciatic nerve blocked in the popliteal area
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the medial area of the lower leg that is innervated by the femoral nerve
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in order to completely block the lower leg and foot what needs to be done
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the addition of a saphenous or femoral block to the sciatic block is required
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the tibial nerve is generally easy to find where and why
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*easy to find in the popliteal space
*b/c it lies closest to the skin at that point |
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the tibial nerve lies next to what
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the popliteal artery
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the sciatic nerve bifurcates into what at approx 8 to 10 cm cephlad of the popliteal crease
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the tibial and common peroneal nerves
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when performing a popliteal block with US where should injection of the LA be
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above the bifurcation of the sciatic nerve
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what is the postioning for a popliteal sciatic block with US
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*pt should be prone or lateral
*position yourself to have access to the popliteal space and thigh *US machine should be opposite you |
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when scanning for a popliteal sciatic you should place the probe where
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over the popliteal crease
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when scanning with US for a popliteal sciatic block what should scanning depth be set at
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4-5 cm
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when scanning for a popliteal sciatic block with US what should you identify first
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the popliteal artery
-be careful not to mistake this for the vein that is freq seen there |
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when scannin for a popliteal sciatic block with US what should be done after the popliteal artery is identified
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look cephald and lateral for the tibial nerve
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when perfoming a popliteal sciatic block with US where should you place the block
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in the area where the 2 nerves (common peroneal & tibial) lie side by side
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when performing a popliteal sciatic block with US if at any time you feel like you may be mistaking tendon for nerve you can do what
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flex the knee
-tendons move, nerves dont |
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the fascia iliaca block with US is a simple block for post-op pain relief in what procedures
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procedures involving:
*hip *ant thigh *knee |
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fascia iliaca block with US is esp useful when
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*fx hips
*proximal to mid-femur fx *total hip athroplasty |
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what are the 2 "pops" with a fascia iliaca
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*1st pop is through fascia lata
*2nd pop is through ilicus fascia |
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what is the positioning with fascia iliaca with US
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*pt is supine
*stand alongside upper thigh *US machine should be opposite your position |
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when scanning with fascia iliaca with US where should you place the probe
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in a perpendicular orientation over the inguinal ligament b/t the ant superior iliac spine & the femoral artery
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what should you locate with the probe when scanning for a fascia iliaca with US
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*femoral artery
*edge of ilium |
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when scanning for a fascia iliaca with US the muscle overlying the bone is what
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ILIOSOAS
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when scanning for a fascia iliaca with US the bright band covering the muscle is what
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ILIACUS FASCIA
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with needle approach for a facsia iliaca with US what is the best approach
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IN PLANE tech
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how should you insert the needle for a fascia iliaca with US
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with the bevel up near the inferior edge of the probe
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when performing a fascia iliaca with US while advancing the needle what should occur
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you should feel the resistance of the fascial layer
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when performing a fascia iliaca with US after puncturing the iliacus fascia what should you do
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stop advancement so that the needle tip lies close to the most superficial level of the iliopsoas muscle
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when performing a fascia iliaca with US be sure the LA volume is spreading in what direction
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SUPERIOR
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