<p begin="00:00:07.889" end="00:00:09.349" style="s2">- [Voiceover] A linear array transducer</p>
<p begin="00:00:09.349" end="00:00:12.631" style="s2">with a nerve exam type is used<br />to perform ultrasound guided</p>
<p begin="00:00:12.631" end="00:00:14.687" style="s2">popliteal nerve block.</p>
<p begin="00:00:14.687" end="00:00:17.850" style="s2">The target depth is<br />approximately 2 to 4 centimeters</p>
<p begin="00:00:17.850" end="00:00:20.373" style="s2">in an 80 kilogram adult.</p>
<p begin="00:00:20.373" end="00:00:23.568" style="s2">The patient is positioned in<br />a lateral decubitus position</p>
<p begin="00:00:23.568" end="00:00:26.091" style="s2">with the hip and knee slightly flexed.</p>
<p begin="00:00:26.091" end="00:00:28.135" style="s2">The transducer is placed transversely</p>
<p begin="00:00:28.135" end="00:00:31.135" style="s2">on the popliteal skin<br />crease with the orientation</p>
<p begin="00:00:31.135" end="00:00:33.388" style="s2">marker directed laterally.</p>
<p begin="00:00:33.388" end="00:00:36.393" style="s2">The transducer should be<br />moved medially and laterally</p>
<p begin="00:00:36.393" end="00:00:40.222" style="s2">to identify the dark round<br />pulsatile popliteal artery.</p>
<p begin="00:00:40.222" end="00:00:43.492" style="s2">The compressible poplital<br />vein can be seen superior</p>
<p begin="00:00:43.492" end="00:00:45.695" style="s2">to the popliteal artery.</p>
<p begin="00:00:45.695" end="00:00:49.145" style="s2">The tibial nerve lies<br />superficial to the popliteal vein</p>
<p begin="00:00:49.145" end="00:00:52.668" style="s2">and appears as a bright<br />hyperechoic oval structure.</p>
<p begin="00:00:52.668" end="00:00:55.331" style="s2">The transducer should be slowly translated</p>
<p begin="00:00:55.331" end="00:00:57.926" style="s2">up the posterior thigh<br />to identify the point</p>
<p begin="00:00:57.926" end="00:01:00.976" style="s2">where the peroneal and tibial nerves join.</p>
<p begin="00:01:00.976" end="00:01:04.783" style="s2">The ideal point for needle<br />insertion is at or just below</p>
<p begin="00:01:04.783" end="00:01:07.763" style="s2">the split of the tibial<br />and peroneal nerves.</p>
<p begin="00:01:07.763" end="00:01:11.138" style="s2">The needles is advanced<br />using an in-plane technique.</p>
<p begin="00:01:11.138" end="00:01:14.455" style="s2">The needle is positioned<br />1 to 2 centimeters lateral</p>
<p begin="00:01:14.455" end="00:01:18.534" style="s2">to the transducer and<br />advanced under the transducer.</p>
<p begin="00:01:18.534" end="00:01:20.831" style="s2">The initial end point for<br />the needle is immediately</p>
<p begin="00:01:20.831" end="00:01:22.906" style="s2">beside the tibial nerve.</p>
<p begin="00:01:22.906" end="00:01:25.326" style="s2">Local anesthetic should<br />be principally injected</p>
<p begin="00:01:25.326" end="00:01:27.880" style="s2">around the tibial nerve,<br />as it is responsible</p>
<p begin="00:01:27.880" end="00:01:31.963" style="s2">for the majority of the<br />innervation of the foot.</p>

<p begin="00:00:07.596" end="00:00:09.143" style="s2">- [Voiceover] A curved array transducer</p>
<p begin="00:00:09.143" end="00:00:11.456" style="s2">with a nerve exam type is used to perform</p>
<p begin="00:00:11.456" end="00:00:14.407" style="s2">a ultrasound guided sciatic nerve block.</p>
<p begin="00:00:14.407" end="00:00:17.696" style="s2">The target depth is approximately<br />four to six centimeters</p>
<p begin="00:00:17.696" end="00:00:20.063" style="s2">in an 80 kilogram adult.</p>
<p begin="00:00:20.063" end="00:00:23.396" style="s2">The patient is positioned in<br />a lateral decubitus position</p>
<p begin="00:00:23.396" end="00:00:25.591" style="s2">with the hip and knee flexed.</p>
<p begin="00:00:25.591" end="00:00:28.711" style="s2">The transducer is placed<br />between the greater trochanter</p>
<p begin="00:00:28.711" end="00:00:31.763" style="s2">and the ischial tuberosity<br />in a transverse position</p>
<p begin="00:00:31.763" end="00:00:34.303" style="s2">just proximal to the gluteal fold</p>
<p begin="00:00:34.303" end="00:00:37.479" style="s2">with the orientation<br />marker directed laterally.</p>
<p begin="00:00:37.479" end="00:00:39.056" style="s2">The bony landmarks will appear</p>
<p begin="00:00:39.056" end="00:00:43.374" style="s2">as bright hyperechoic crescents<br />with posterior shadowing.</p>
<p begin="00:00:43.374" end="00:00:44.886" style="s2">There are several layers of tissue</p>
<p begin="00:00:44.886" end="00:00:47.454" style="s2">between the bony landmarks,<br />which should be identified</p>
<p begin="00:00:47.454" end="00:00:51.249" style="s2">from superficial to deep,<br />including adipose tissue,</p>
<p begin="00:00:51.249" end="00:00:55.303" style="s2">the gluteus maximus muscle<br />and quadratus femoris muscle.</p>
<p begin="00:00:55.303" end="00:00:58.156" style="s2">The sciatic nerve lies<br />deep to the gluteus maximus</p>
<p begin="00:00:58.156" end="00:01:01.744" style="s2">and superficial to the<br />quadratus femoris muscle.</p>
<p begin="00:01:01.744" end="00:01:04.321" style="s2">It appears as a bright hyperechoic oval</p>
<p begin="00:01:04.321" end="00:01:06.888" style="s2">or triangular shaped density.</p>
<p begin="00:01:06.888" end="00:01:10.176" style="s2">The transducer should be<br />moved slightly cranially</p>
<p begin="00:01:10.176" end="00:01:12.296" style="s2">or caudally from the initial position</p>
<p begin="00:01:12.296" end="00:01:14.357" style="s2">by slightly rocking the transducer</p>
<p begin="00:01:14.357" end="00:01:16.596" style="s2">so the beam is perpendicular to the nerve</p>
<p begin="00:01:16.596" end="00:01:20.739" style="s2">for the best echo reflection<br />if it is difficult to identify.</p>
<p begin="00:01:20.739" end="00:01:23.307" style="s2">When the transducer is<br />moved distally in the thigh,</p>
<p begin="00:01:23.307" end="00:01:26.138" style="s2">the sciatic nerve becomes<br />more oval in shape</p>
<p begin="00:01:26.138" end="00:01:29.267" style="s2">and is found more superficially<br />between the biceps femoris</p>
<p begin="00:01:29.267" end="00:01:31.675" style="s2">and abductor magnus muscles.</p>
<p begin="00:01:31.675" end="00:01:34.922" style="s2">The needle is advanced<br />using an in plane technique.</p>
<p begin="00:01:34.922" end="00:01:38.036" style="s2">The needle is positioned one<br />to two centimeters lateral</p>
<p begin="00:01:38.036" end="00:01:42.219" style="s2">to the transducer and advanced<br />slowly under the transducer.</p>
<p begin="00:01:42.219" end="00:01:43.828" style="s2">The initial end point for the needle</p>
<p begin="00:01:43.828" end="00:01:46.907" style="s2">is just lateral and deep to the nerve.</p>
<p begin="00:01:46.907" end="00:01:49.538" style="s2">The local anesthetic is<br />injected incrementally</p>
<p begin="00:01:49.538" end="00:01:51.011" style="s2">close to the nerve.</p>
<p begin="00:01:51.011" end="00:01:53.355" style="s2">For a successful block, a spread of locals</p>
<p begin="00:01:53.355" end="00:01:55.500" style="s2">should be observed around the medial side</p>
<p begin="00:01:55.500" end="00:01:58.250" style="s2">or tibial component of the nerve.</p>