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(min-width:1420px) and (max-width:1919px){body.postid-35804 .wd-content-area.site-content,body.postid-35804 .wd-entry-content{max-width:1180px!important}.sr-bl-2026{max-width:1180px}.sr-light-toc{display:block;left:auto;right:4px;width:114px;padding:12px 7px}.sr-bl-2026 .sr-light-toc__links a{font-size:9.5px;padding:5px 3px}.sr-bl-2026 p.sr-light-toc__note{font-size:11px}.sr-light-toc .sr-crisp-consult-btn{font-size:9px;padding:10px 3px}.sr-bl-2026 .sr-light-toc__progress{font-size:9px}}\n@media (min-width:1920px){.sr-light-toc{display:block}body.postid-35804 .wd-content-area.site-content,body.postid-35804 .wd-entry-content{max-width:1200px!important}.sr-bl-2026{max-width:1200px}}\n@media (max-width:900px){.sr-author-grid{grid-template-columns:1fr;gap:0}.sr-bl-dev__grid{grid-template-columns:1fr}.sr-bl-dev__col+.sr-bl-dev__col{border-left:0;border-top:1px solid var(--rule)}.sr-bl-rels{grid-template-columns:1fr 1fr}.sr-final-cta{grid-template-columns:1fr;gap:24px}.sr-bl-points{grid-template-columns:1fr 1fr}.sr-bl-2026 .sr-bl-pt:nth-child(3){border-left:0}.sr-bl-2026 .sr-bl-pt:nth-child(n+3){border-top:1px solid rgba(255,255,255,.1)}}\n@media (max-width:640px){.sr-bl-2026{font-size:18px;padding:0 0 60px}.sr-byline__author{width:100%;align-items:center;flex-wrap:wrap;gap:6px 10px}.sr-byline b{white-space:nowrap}.sr-byline{gap:12px 18px}.sr-bl-badge__x{display:none}.sr-bl-points{grid-template-columns:1fr}.sr-bl-2026 .sr-bl-pt{border-left:0}.sr-bl-2026 .sr-bl-pt+.sr-bl-pt{border-top:1px solid rgba(255,255,255,.1)}.sr-bl-rt__seg em{display:none}.sr-bl-band{padding:28px 20px 24px}.sr-bl-rels{grid-template-columns:1fr}.sr-bl-txbody{padding:20px 18px 4px}.sr-bl-dev__col{padding:22px 20px}.sr-bl-dev__links{padding:16px 20px}.sr-bl-dev__links a{flex:1 1 auto;text-align:center}#quick-answer{padding:22px 20px 8px}#quick-answer p{font-size:18.5px}.sr-final-cta{padding:28px 20px 26px}.sr-bl-spec li{grid-template-columns:1fr;gap:2px}.sr-bl-pt__h{font-size:15px}.sr-bl-play svg{width:62px;height:62px}}\n@media (prefers-reduced-motion:reduce){.sr-bl-2026 *,.sr-light-toc *{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important}}<\/style>\n<div class=\"sr-mast\">\n<p class=\"sr-deck\">A four-point lung survey run end to end on a handheld probe &mdash; pleural sliding, A-lines, B-lines and the curtain sign at the base &mdash; with every point timestamped, the settings read off the device screen, and the whole recording transcribed.<\/p>\n<div class=\"sr-author-panel\" data-suresult-author-panel aria-label=\"Article authors\">\n<p class=\"sr-byline__label\">Written and clinically reviewed by<\/p>\n<div class=\"sr-author-grid\">\n<article class=\"sr-author-card\" data-sr-author=\"fernando-mariz-md\">\n<div class=\"sr-author-card__head\"><img src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/fernando-mariz-md-author-avatar.png\" alt=\"Fernando Mariz, MD\" width=\"42\" height=\"42\" loading=\"lazy\" decoding=\"async\"><span class=\"sr-author-card__id\"><b>Fernando Mariz, MD<\/b><span class=\"sr-author-card__role\">Gynecology, pelvic surgery, sonography<\/span><\/span><\/div>\n<details data-sr-author-bio>\n<summary>About Dr. Mariz<\/summary>\n<p>I am Dr. Fernando Mariz, a gynecology and pelvic surgery physician practicing in New York City. Before my medical career, I served in the U.S. Marine Corps, where I developed the discipline, focus, and steadiness that continue to shape the way I care for patients today. At Maiden Lane Medical, my work covers women&rsquo;s health, preventive care, sonography, pelvic pain, abnormal uterine bleeding, and minimally invasive gynecologic procedures.<\/p>\n<p class=\"sr-author-card__links\"><a href=\"https:\/\/maidenlanemedical.com\/profile\/fernando-mariz-md\/\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">Maiden Lane Medical profile<\/a> &middot; <a href=\"https:\/\/weillcornell.org\/fernando-marizmd-9639\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">Weill Cornell Medicine<\/a><\/p>\n<\/details>\n<\/article>\n<article class=\"sr-author-card\" data-sr-author=\"jailyn-avila-md\">\n<div class=\"sr-author-card__head\"><img src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/jailyn-avila-md-author-avatar.png\" alt=\"Jailyn Avila, MD\" width=\"42\" height=\"42\" loading=\"lazy\" decoding=\"async\"><span class=\"sr-author-card__id\"><b>Jailyn Avila, MD<\/b><span class=\"sr-author-card__role\">Emergency medicine, POCUS education<\/span><\/span><\/div>\n<details data-sr-author-bio>\n<summary>About Dr. Avila<\/summary>\n<p>I am Dr. Jailyn Avila, an emergency medicine physician, educator, and digital health innovator based in Southern California. My clinical work is rooted in emergency care, while my teaching focuses on point-of-care ultrasound, residency education, and practical training for physicians. Through my roles with Emergent Medical Associates, UHS SoCal MEC Emergency Medicine Residency, Core Ultrasound, and FemInEM, I work at the intersection of patient care, medical education, and accessible digital learning.<\/p>\n<p class=\"sr-author-card__links\"><a href=\"https:\/\/jailynavila.com\/\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">Personal site<\/a> &middot; <a href=\"https:\/\/feminem.org\/about\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">FemInEM<\/a><\/p>\n<\/details>\n<\/article>\n<\/div>\n<p class=\"sr-author-meta\"><span class=\"sr-verified-badge\">Verified authors<\/span><span>Updated <b>September 5, 2026<\/b><\/span><\/p>\n<\/div>\n<\/div>\n<figure class=\"sr-bl-stage\">\n<button class=\"sr-bl-player\" id=\"sr-bl-player\" type=\"button\" aria-label=\"Play the 9-minute lung ultrasound walkthrough\"><br \/>\n<img src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/lung-ultrasound-pleural-line-m-mode-poster.jpg\" alt=\"Live lung ultrasound on a handheld probe: bright pleural line in B-mode with a full-width M-mode strip below it, MSK preset at 60 mm depth and H10.0 MHz\" width=\"1920\" height=\"1080\" fetchpriority=\"high\" decoding=\"async\"><br \/>\n<span class=\"sr-bl-play\"><svg viewBox=\"0 0 84 84\" aria-hidden=\"true\" focusable=\"false\"><circle cx=\"42\" cy=\"42\" r=\"40\" fill=\"rgba(10,14,18,.62)\" stroke=\"rgba(255,255,255,.9)\" stroke-width=\"1.6\"\/><path d=\"M34.5 28.2 L58 42 L34.5 55.8 Z\" fill=\"#fff\"\/><\/svg><\/span><br \/>\n<span class=\"sr-bl-badge\"><span>9:28<\/span><span class=\"sr-bl-badge__k\">13 key moments<\/span><span class=\"sr-bl-badge__x\">Transcript below<\/span><\/span><br \/>\n<\/button><figcaption class=\"sr-bl-cap\"><b>Published on the Suresult channel on 12 October 2025.<\/b> The presenting clinician scans himself, which he says at 0:43. The poster above and the frozen frame further down are both taken from this recording.<\/figcaption><\/figure>\n<section id=\"quick-answer\">\n<h2>Quick answer<\/h2>\n<p><strong>B-lines are vertical, laser-like artifacts that rise from the pleural line, run to the bottom of the screen without fading, and mean there is fluid in the lung at that window.<\/strong> A-lines are their opposite number: horizontal repeats of the pleural line, the signature of air-filled lung, and present in a healthy chest and in a pneumothorax alike, which is why they never settle a question on their own. One or two B-lines in a single intercostal space can be normal, particularly low down and in older patients; three or more in one space is interstitial syndrome at that window, and the conditions behind it are pulmonary oedema, pneumonia, ARDS and interstitial lung disease. The walkthrough on this page runs a four-point survey on a handheld probe and finds none of them &mdash; every window comes back A-lines plus sliding, which is exactly what a normal lung looks like, and the B-line, effusion and consolidation pictures are shown as reference images at 2:28 and 2:43 rather than acquired live. That is the honest shape of the recording, and it is still the fastest way I know to learn the finding: you cannot recognise a wet lung until you know precisely what a dry one looks like at 10 MHz. Start at 5:36 if you want the scanning, at 0:43 if you want the pictures.<\/p>\n<p class=\"sr-answer-note\">Looking for a device rather than the exam? The <a href=\"https:\/\/suresultmed.com\/specialty\/handheld-ultrasound-for-pulmonology\/\">pulmonology hub<\/a> covers the models used for chest work, and the <a href=\"https:\/\/suresultmed.com\/shop\/handheld-ultrasounds\/d3ultra-multipurpose-handheld-ultrasound\/\">D3Ultra product page<\/a> carries the full specification and current price.<\/p>\n<\/section>\n<section id=\"four-points\">\n<div class=\"sr-bl-band\">\n<p class=\"sr-bl-band__eye\">The four points<\/p>\n<h2>Where the probe goes, and what each point settles<\/h2>\n<p class=\"sr-bl-band__sub\">The four windows in the order they are scanned, with the question each one is there to answer and the findings called out loud at it. Click any point to jump the video to it.<\/p>\n<div class=\"sr-bl-points\"><a class=\"sr-bl-pt\" href=\"#t=336\" data-sr-seek=\"336\"><span class=\"sr-bl-pt__n\">01<\/span><span class=\"sr-bl-pt__z\">Anterior upper zone<\/span><span class=\"sr-bl-pt__h\">Second intercostal space<\/span><span class=\"sr-bl-pt__q\">Is the pleura sliding, and are the lines A or B?<\/span><span class=\"sr-bl-pt__c\"><i>A-lines<\/i><i>seashore sign<\/i><\/span><span class=\"sr-bl-pt__t\">5:36<\/span><\/a><a class=\"sr-bl-pt\" href=\"#t=392\" data-sr-seek=\"392\"><span class=\"sr-bl-pt__n\">02<\/span><span class=\"sr-bl-pt__z\">Anterior lower zone<\/span><span class=\"sr-bl-pt__h\">Fifth to sixth rib<\/span><span class=\"sr-bl-pt__q\">Same question, better window \u2014 this is where sliding was easiest to call.<\/span><span class=\"sr-bl-pt__c\"><i>pleural sliding<\/i><i>seashore sign<\/i><\/span><span class=\"sr-bl-pt__t\">6:32<\/span><\/a><a class=\"sr-bl-pt\" href=\"#t=427\" data-sr-seek=\"427\"><span class=\"sr-bl-pt__n\">03<\/span><span class=\"sr-bl-pt__z\">Lateral zone<\/span><span class=\"sr-bl-pt__h\">Lateral chest wall<\/span><span class=\"sr-bl-pt__q\">Sliding again, and a deliberate check that no B-lines have appeared.<\/span><span class=\"sr-bl-pt__c\"><i>pleural sliding<\/i><i>no B-lines<\/i><\/span><span class=\"sr-bl-pt__t\">7:07<\/span><\/a><a class=\"sr-bl-pt\" href=\"#t=458\" data-sr-seek=\"458\"><span class=\"sr-bl-pt__n\">04<\/span><span class=\"sr-bl-pt__z\">Dependent corner<\/span><span class=\"sr-bl-pt__h\">PLAPS \u2014 posterolateral inferior<\/span><span class=\"sr-bl-pt__q\">The corner where fluid collects. Effusion, consolidation, curtain sign.<\/span><span class=\"sr-bl-pt__c\"><i>curtain sign<\/i><i>lung\u2013liver interface<\/i><\/span><span class=\"sr-bl-pt__t\">7:38<\/span><\/a><\/div>\n<div class=\"sr-bl-rt\"><span class=\"sr-bl-rt__seg sr-bl-rt__seg--teach\" style=\"width:59.2%\"><b>0:00<\/b><em>Teaching, reference images and the protocol argument<\/em><\/span><span class=\"sr-bl-rt__seg sr-bl-rt__seg--live\" style=\"width:34.5%\"><b>5:36<\/b><em>The four points, scanned live<\/em><\/span><span class=\"sr-bl-rt__seg sr-bl-rt__seg--close\" style=\"width:6.3%\"><b>8:52<\/b><em>Close<\/em><\/span><\/div>\n<p class=\"sr-bl-band__key\"><span><i style=\"background:#c98a2b\"><\/i>teaching, reference images and the protocol argument<\/span><span><i style=\"background:#3f9d96\"><\/i>the four points, scanned live<\/span><span><i style=\"background:rgba(255,255,255,.28)\"><\/i>close<\/span><\/p>\n<p class=\"sr-bl-band__note\">The BLUE protocol proper is a three-point examination. The four-point survey demonstrated here is the presenting clinician&#8217;s own extension of it, and he says so at 0:00. He also recommends adding posterior points whenever the patient can sit forward, on the grounds that the back is easier to reach than the front and consolidation shows there anyway; those points are argued for from 3:36 but are not scanned on camera.<\/p>\n<\/div>\n<\/section>\n<section id=\"key-moments\">\n<p class=\"sr-bl-krow\">Timestamped<\/p>\n<h2>Key moments, with the settings<\/h2>\n<p>The third column is the part that is normally missing from a scan video: the preset, depth and transmit frequency showing on the device at that moment. What is striking on this recording is that they never change. One preset, one depth, one frequency carry all four points &mdash; and that frequency is the ceiling of what this probe&#8217;s linear array offers.<\/p>\n<div class=\"sr-table-wrap\">\n<table class=\"sr-bl-km\">\n<colgroup>\n<col style=\"width:82px\">\n<col>\n<col style=\"width:268px\"><\/colgroup>\n<thead>\n<tr>\n<th>Time<\/th>\n<th>What is on screen<\/th>\n<th>Transducer, preset, depth, frequency<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=0\" data-sr-seek=\"0\">0:00<\/a><\/td>\n<td><b>Four points, and why<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">The exam is framed before the probe is picked up: three lobes plus the dependent corner where fluid collects. The BLUE protocol proper uses three points; the four-point survey demonstrated here is the presenting clinician&#8217;s own extension of it, and he says so.<\/span><\/td>\n<td class=\"sr-bl-set\">Teaching segment \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=43\" data-sr-seek=\"43\">0:43<\/a><\/td>\n<td><b>Pleural sliding \u2014 the ants sign<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">The single finding the whole exam turns on. Sliding is described as ants moving along the wall of the cavity; if the pleura is not moving there, the lung is not against the chest wall.<\/span><\/td>\n<td class=\"sr-bl-set\">Reference clip on a slide \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=63\" data-sr-seek=\"63\">1:03<\/a><\/td>\n<td><b>A-lines, M-mode, seashore versus barcode<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">A-lines named as a reverberation artifact that repeats at regular intervals below the pleura, and stated plainly to be present in normal lung and in pneumothorax alike. M-mode is offered as the tie-breaker: a sandy seashore pattern where the lung moves, a flat barcode where it does not.<\/span><\/td>\n<td class=\"sr-bl-set\">Reference clip on a slide \u00b7 B and M mode shown<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=110\" data-sr-seek=\"110\">1:50<\/a><\/td>\n<td><b>The curtain sign at the lung base<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">The lung base, where aerated lung slides across the liver and blocks the view of it. What would replace that on an abnormal scan is spelled out: an anechoic triangle above the diaphragm for effusion, or a lung you can see straight through for consolidation.<\/span><\/td>\n<td class=\"sr-bl-set\">Reference clip on a slide \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=148\" data-sr-seek=\"148\">2:28<\/a><\/td>\n<td><b>What effusion and consolidation look like instead<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">Two abnormal reference images: a pleural effusion, and a consolidated lung transmitting sound well enough that the spleen or liver is visible through it.<\/span><\/td>\n<td class=\"sr-bl-set\">Reference images on a slide \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=163\" data-sr-seek=\"163\">2:43<\/a><\/td>\n<td><b>B-lines, comet tails and confluent B-lines<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">Wet lung. Comet-tail artifacts rising from the pleural line raise the suspicion of pneumonia, and when there are enough of them that they merge into one broad band the finding is called out as strongly suggestive.<\/span><\/td>\n<td class=\"sr-bl-set\">Reference images on a slide \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=185\" data-sr-seek=\"185\">3:05<\/a><\/td>\n<td><b>How accurate the BLUE protocol is<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">Sensitivity and specificity for the BLUE protocol are quoted from a published table on screen as being in the eighties and nineties.<\/span><\/td>\n<td class=\"sr-bl-set\">Cited table on a slide \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=216\" data-sr-seek=\"216\">3:36<\/a><\/td>\n<td><b>Why these points, and scanning from the back<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">The B in BLUE stands for bedside, and that constrains access: a supine patient gives you the front and a little of the side. Sitting the patient up opens the back, which is easier to reach and is where consolidation shows anyway.<\/span><\/td>\n<td class=\"sr-bl-set\">Teaching segment \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=280\" data-sr-seek=\"280\">4:40<\/a><\/td>\n<td><b>Let the clinical question drive the look<\/b><span class=\"sr-bl-flag\">teaching<\/span><span class=\"sr-bl-screen\">The most portable idea in the recording: decide what you are asking before you look. Chasing pneumonia means watching for B-lines; chasing pneumothorax means watching the pleura and nothing else. A normal lung scan in a breathless patient is a reason to go and look at the legs.<\/span><\/td>\n<td class=\"sr-bl-set\">Teaching segment \u00b7 no device panel on screen<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=336\" data-sr-seek=\"336\">5:36<\/a><\/td>\n<td><b>Point 1 \u2014 second intercostal space<\/b><span class=\"sr-bl-screen\">First live acquisition. The probe goes between the ribs at the second rib level, the subject takes a breath, M-mode is switched on. An A-line is identified, no comet tails, and the M-mode strip is read as seashore rather than barcode.<\/span><\/td>\n<td class=\"sr-bl-set\">Linear \u00b7 MSK preset \u00b7 D 60 mm \u00b7 F H10.0 MHz \u00b7 GN 105 dB \u00b7 DR 80 \u00b7 B + M<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=392\" data-sr-seek=\"392\">6:32<\/a><\/td>\n<td><b>Point 2 \u2014 fifth to sixth rib<\/b><span class=\"sr-bl-screen\">The clearest sliding in the recording, and the point where the rule-out logic is stated outright: you cannot have pleural sliding if the lung is not attached to the chest wall, so sliding here settles the question at this window.<\/span><\/td>\n<td class=\"sr-bl-set\">Linear \u00b7 MSK preset \u00b7 D 60 mm \u00b7 F H10.0 MHz \u00b7 GN 105 dB \u00b7 DR 80 \u00b7 B + M<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=427\" data-sr-seek=\"427\">7:07<\/a><\/td>\n<td><b>Point 3 \u2014 lateral wall<\/b><span class=\"sr-bl-screen\">More gel, arm raised, probe onto the lateral chest wall. Sliding is seen again and B-lines are explicitly excluded at this window.<\/span><\/td>\n<td class=\"sr-bl-set\">Linear \u00b7 MSK preset \u00b7 D 60 mm \u00b7 F H10.0 MHz \u00b7 GN 105 dB \u00b7 DR 80 \u00b7 B + M<\/td>\n<\/tr>\n<tr>\n<td class=\"sr-bl-t\"><a href=\"#t=458\" data-sr-seek=\"458\">7:38<\/a><\/td>\n<td><b>Point 4 \u2014 PLAPS, and reading the base<\/b><span class=\"sr-bl-screen\">The posterolateral inferior point, taken down until the bottom of the lung comes into frame. M-mode is switched off. Rib, liver and lung are named on a frozen frame, the curtain sweeping across the liver with the diaphragm, and the abnormal versions of that picture are described.<\/span><\/td>\n<td class=\"sr-bl-set\">Linear \u00b7 MSK preset \u00b7 D 60 mm \u00b7 F H10.0 MHz \u00b7 GN 105 dB \u00b7 DR 80 \u00b7 B + M, then B only<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"sr-table-note\">Settings transcribed from the device interface visible in the recording. Depth is the D value on screen; frequency is the F value, harmonic. The first nine rows are taught against slides and reference images rather than scanned live, so no device panel is on screen for most of them. M-mode is switched on at 5:36 and switched off again inside the fourth point.<\/p>\n<\/section>\n<section id=\"what-it-shows\">\n<p class=\"sr-bl-krow\">Reading the images<\/p>\n<h2>What this scan shows<\/h2>\n<p>The pleural line is the only structure this exam really needs. It sits a centimetre below the skin, framed between two rib shadows, and it shimmers as the patient breathes. That shimmer is lung sliding, and the whole survey turns on it: if the two pleural layers are still in contact they slide against each other, and a pneumothorax at that window is ruled out. Absent sliding is not by itself a diagnosis &mdash; it says only that the lung is not moving against the chest wall there.<\/p>\n<p>Everything below the pleural line is artifact, because air-filled lung reflects almost all the sound that reaches it. A-lines are horizontal echoes of the pleural line repeating at even intervals; they are what dry lung looks like, and they appear in a pneumothorax too. B-lines are the vertical answer: laser-like bands that start at the pleura, run off the bottom of the screen without fading, erase the A-lines they cross, and swing with the breath. They exist only where there is fluid. Three or more in one intercostal space reads as interstitial syndrome at that window; enough of them and they merge into a single broad white band.<\/p>\n<figure class=\"sr-bl-fig\">\n<img src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/curtain-sign-lung-base-ultrasound.jpg\" alt=\"Frozen lung-base frame on a handheld ultrasound: bright air-filled lung across the upper sector blocking the view of the liver behind it, MSK preset at 60 mm depth and H10.0 MHz\" width=\"1280\" height=\"720\" loading=\"lazy\" decoding=\"async\"><figcaption class=\"sr-bl-figcap\"><b>The lung base, frozen at 7:57.<\/b> The frame the presenting clinician steps through while naming rib, liver and lung, and the picture he calls the curtain sign: air-filled lung sweeping across with the diaphragm and blocking the view of the liver behind it. What replaces it on an abnormal scan is an anechoic wedge above the diaphragm, or a lung solid enough to see straight through. Linear array &middot; MSK preset &middot; D 60 mm &middot; F H10.0 MHz &middot; GN 105 dB &middot; DR 80.<\/figcaption><\/figure>\n<p>M-mode is the tie-breaker when sliding is too subtle to call by eye: a granular seashore below a smooth band where the lung moves, flat parallel lines &mdash; the barcode sign &mdash; where it does not. The settings matter more than they look. All four points run on the linear array at 10 MHz and 60 mm, the top of this probe&#8217;s range and the right choice for a structure a centimetre deep. Take that setting to an effusion ten centimetres down at the base and it will not reach; I would move to the convex array there.<\/p>\n<\/section>\n<section id=\"transcript\">\n<p class=\"sr-bl-krow\">Verbatim<\/p>\n<h2>Full transcript<\/h2>\n<details class=\"sr-bl-tx\" id=\"sr-bl-transcript\" data-sr-transcript=\"1\" open>\n<summary>Transcript &mdash; 9:28, 18 passages<\/summary>\n<div class=\"sr-bl-txbody\">\n<p class=\"sr-bl-txnote\"><span>Transcribed from the recording and edited for readability; square brackets mark an editorial clarification, and every timestamp jumps the video.<\/span><\/p>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Framing the exam<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=0\" data-sr-seek=\"0\">0:00<\/a>[The presenting clinician introduces himself.] Today we&#8217;re going to do a very, very quick sample lung scan using a Suresult D3Ultra handheld ultrasound unit. My version of the exam uses four points. Why do I pick four points? If you look at the lobes, I get this lobe, this lobe, this lobe, and then I pick the bottom corner where fluid is likely to collect. There are many similar protocols. The BLUE protocol uses three points instead of four points, and in general the more points you do, the better. So if you want, you can do the posterior wall; and if you don&#8217;t like three, you can pick four, five, six \u2014 you can check between every rib if you want.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">What you are looking for<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=43\" data-sr-seek=\"43\">0:43<\/a>Here, just on myself, I wanted some samples of normals to talk about what we are looking for. We&#8217;re looking for pleural sliding \u2014 it sort of looks like ants moving along the wall of the cavity. If it&#8217;s not moving along the wall of the cavity, guess what: you have a pneumothorax. The lung isn&#8217;t there, or the lung isn&#8217;t moving.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=63\" data-sr-seek=\"63\">1:03<\/a>In general, the rest of the appearance of the lung \u2014 you don&#8217;t really see into the lung, because the lung is full of air. So pneumothorax and regular normal lung look the same. When you get past the pleura you do see something they call an A-line, which is just a reverberation artifact: sound bouncing back and forth here makes this line repeat itself at regular intervals. That is a sign that&#8217;s either pneumothorax or normal lung. And then you look for pleural sliding, and if you see pleural sliding you can rule out pneumothorax. Some people like to use M-mode and they look for the seashore sign \u2014 this looks like a sandy beach and this looks like the water, and that&#8217;s what you should see. And if you see something more that looks like this, like just a barcode, then that&#8217;s a sign of a pneumothorax.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=110\" data-sr-seek=\"110\">1:50<\/a>And again, just check different locations; we see the same thing. We&#8217;re looking for ants crawling across the pleura. And here at that corner, this is called curtain sign, because you can&#8217;t see through lungs normally, right? So what we&#8217;re seeing is the lung basically move, and it&#8217;s covering up \u2014 it prevents us from seeing within the liver. If there was fluid we would see a corner of hypoechoic or anechoic fluid, sort of a triangle right here. And if the lungs had pneumonia, were full and solid, we&#8217;d be able to see through the lungs.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=148\" data-sr-seek=\"148\">2:28<\/a>So here&#8217;s just an example of what an effusion would look like. Here&#8217;s another case where we have consolidation, so we can basically see through the lungs \u2014 we can see the spleen or liver, depending on what side of the body you&#8217;re on.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=163\" data-sr-seek=\"163\">2:43<\/a>This reverberation artifact is considered normal or pneumothorax. If you get something called B-lines or comet-tail artifacts, that means the lungs are wet; it increases your suspicion for pneumonia. And if you get something that looks like this \u2014 basically these lines, there&#8217;s so many of them that they sort of bunch up into just one giant line \u2014 that is also very indicative of pneumonia.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">How good it is<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=185\" data-sr-seek=\"185\">3:05<\/a>I mentioned there&#8217;s lots of protocols; the BLUE protocol is quite common. And you can see for the BLUE protocol you get sensitivities and specificities, you know, 80s, 90s. So it&#8217;s pretty good.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=197\" data-sr-seek=\"197\">3:17<\/a>[Promotional segment omitted, 3:17\u20133:36.]<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Why these points<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=216\" data-sr-seek=\"216\">3:36<\/a>So my protocol for the lung exam is basically the BLUE protocol, and the B in BLUE stands for bed, or bedside. So basically if someone&#8217;s lying down, you only have access to the front and maybe a bit of the side, and that&#8217;s it. If you have access \u2014 let&#8217;s say if they&#8217;re sitting like this \u2014 well, you have access to the back. In fact you have easier access to the back than the front, so you can add on more points. Or let&#8217;s say you have a woman, and there are breasts and bras in the way: you can still check a lot of the lung from the back instead of the front. And if you&#8217;re looking for something like pneumonia or consolidation, you&#8217;re going to see that on the back as well as the front, so don&#8217;t worry about missing the two front parts when you have access to the back.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=261\" data-sr-seek=\"261\">4:21<\/a>The reason why this is my recommended protocol is because it&#8217;s just a few points, and the BLUE protocol is a validated set of points to check. So if I follow that, that means your exam is at least as good as the BLUE protocol, which is, you know, 80 to 90-some percent accurate at finding things like pneumonia and pneumothorax.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=280\" data-sr-seek=\"280\">4:40<\/a>And that raises another point. Based on your clinical intuition \u2014 what exactly are you looking for? You might be looking for different things in the images. If you&#8217;re looking for pneumonia, then you don&#8217;t really care about the pleura sliding around; you just care about those B-lines or the C-lines. If you care about a pneumothorax, then you&#8217;re really looking at that pleura and you&#8217;re just going point to point, really focusing on that pleura. Again, if you have time, I guess you can always look at everything, but you want to answer your clinical question. Is there pneumothorax? If that&#8217;s your only clinical question, then you&#8217;re just looking: is the pleura sliding, are there A-lines \u2014 A-lines for a pneumothorax or for a normal lung. And if you find nothing, if you follow that BLUE protocol and you find nothing, normal lung \u2014 and they have lung symptoms \u2014 well, maybe check for a DVT. Maybe it&#8217;s a pulmonary embolism, in which case the lung scan shows normal but they still have trouble breathing.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Point 1<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=336\" data-sr-seek=\"336\">5:36<\/a>So I&#8217;m going to turn on M-mode, because some people like M-mode for looking for seashore sign versus barcode sign. I don&#8217;t really pay attention to that myself; I&#8217;m just going to be looking at the pleura, looking for those ants moving across. I&#8217;m looking for: are they A-lines, B-lines or C-lines. So around second rib, let&#8217;s take a look here. So between the ribs, and take a breath. And we can see we have an A-line here. We&#8217;re not getting comet-tail type artifacts like B-lines, so we have basically an A-line, and we do get a little bit of motion across, and we do get more of a seashore sign instead of the barcode sign.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Point 2<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=392\" data-sr-seek=\"392\">6:32<\/a>And let&#8217;s go to the next point. So normally around, I don&#8217;t know, like fifth, sixth rib. Now this one I can really, really see it. The first one, honestly, I didn&#8217;t see the pleural sliding that clearly; this one you can really see the pleural sliding here. Remember, if you can see the pleura sliding, that rules out \u2014 virtually 100% rules out \u2014 a pneumothorax, because you can&#8217;t have pleural sliding if the lung isn&#8217;t attached to the wall of the thoracic cavity. So if you&#8217;re missing pleural sliding, well, it could be other things; but if you have pleural sliding that rules out pneumothorax. So we have pleural sliding, so I definitely don&#8217;t have pneumothorax.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Point 3<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=427\" data-sr-seek=\"427\">7:07<\/a>So I added more gel, and the next point is over here. And again, we can very clearly see pleural sliding. So that&#8217;s great. And again we&#8217;re not seeing these B-lines or anything that looks like that, so no pneumonia for me.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Point 4<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=458\" data-sr-seek=\"458\">7:38<\/a>And if I move down, now this is posterolateral, inferior. I go down until I hit the bottom of the lungs. In fact, I&#8217;m going to turn off M-mode now.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=477\" data-sr-seek=\"477\">7:57<\/a>Okay, so what are we looking at? Well, particularly if we can go through a few frames here, we have the liver here, and we have \u2014 we have rib, we have liver, and we have the lung. This is called the curtain sign. The lung is covering, because we can&#8217;t see through a lung, so it&#8217;s covering the liver; and as I breathe the lung is \u2014 well, the diaphragm is moving up and down, and so the lung is moving, and so we see this curtain come across the liver and prevent us from seeing anything. So this is normal.<\/p>\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=508\" data-sr-seek=\"508\">8:28<\/a>If we can see through the lungs, that&#8217;s bad. That means there&#8217;s consolidation and the lungs are full of fluid and junk. If there is a large hypoechoic or anechoic collection of fluid here \u2014 here we see it&#8217;s often just this triangle, black triangle \u2014 then we would have a lung effusion, which could be a hemothorax, for example. And that&#8217;s it. Pretty quick.<\/p>\n<\/div>\n<\/section>\n<section class=\"sr-bl-txsec\">\n<h3 class=\"sr-bl-txwin\">Close<\/h3>\n<div class=\"sr-bl-txcol\">\n<p class=\"sr-bl-txp\"><a class=\"sr-bl-txt\" href=\"#t=532\" data-sr-seek=\"532\">8:52<\/a>[Sponsor segment omitted, 8:52\u20139:28.]<\/p>\n<\/div>\n<\/section>\n<\/div>\n<\/details>\n<\/section>\n<section id=\"device\" class=\"sr-choice\">\n<p class=\"sr-bl-krow\">Hardware<\/p>\n<h2>Device and settings<\/h2>\n<p>One probe, one setting, the whole survey. The left column is the published specification; the right column is what the device interface actually showed while this exam was being run, and that second column is the one I would work from if you are reproducing it. For chest work the linear array at 10 MHz is the right default, because the pleura is superficial and resolution beats penetration there. If your lung work is mostly deep effusions and consolidation at the base, a linear-only setup is not a good fit: the convex array is the one that matters there, and this is the wrong setting to copy.<\/p>\n<div class=\"sr-bl-dev\">\n<div class=\"sr-bl-dev__grid\">\n<div class=\"sr-bl-dev__col\">\n<p class=\"sr-bl-dev__h\">Published specification<\/p>\n<p class=\"sr-bl-dev__name\">Suresult D3Ultra<\/p>\n<p class=\"sr-bl-dev__price\">One head, three arrays &mdash; {{SRX_PRICE:28571}}<\/p>\n<ul class=\"sr-bl-spec\">\n<li><b>Linear<\/b><span>7.5 and 10 MHz &middot; depth steps of 20, 40, 60 and 100 mm &middot; 40 mm footprint &mdash; the array this exam runs on<\/span><\/li>\n<li><b>Convex<\/b><span>3.2 and 5.0 MHz &middot; 90 to 300 mm &middot; 45&deg; &mdash; the one to reach a deep basal effusion<\/span><\/li>\n<li><b>Phased<\/b><span>3.2 and 5.0 MHz &middot; 90 to 300 mm &middot; 60&deg;<\/span><\/li>\n<li><b>Modes used here<\/b><span>B, and B+M for the seashore strip; Color, Power and PW Doppler also available<\/span><\/li>\n<li><b>Gain<\/b><span>30 to 105 dB &mdash; this scan sits at the ceiling of that range<\/span><\/li>\n<li><b>Dynamic range<\/b><span>40 to 110, in ten steps<\/span><\/li>\n<li><b>Array<\/b><span>192 elements &middot; 64 channels &middot; 256 grey levels<\/span><\/li>\n<li><b>Body<\/b><span>156 &times; 65 &times; 20 mm &middot; 263 g &middot; 2 h continuous scanning<\/span><\/li>\n<\/ul>\n<\/div>\n<div class=\"sr-bl-dev__col\">\n<p class=\"sr-bl-dev__h\">Read off the screen in this recording<\/p>\n<ul class=\"sr-bl-spec\">\n<li><b>Array<\/b><span>Linear &middot; MSK preset, unchanged at all four points<\/span><\/li>\n<li><b>Depth<\/b><span>D 60 mm &middot; the middle of the linear array&#8217;s four steps<\/span><\/li>\n<li><b>Frequency<\/b><span>F H10.0 MHz, harmonic &middot; the top of the linear range<\/span><\/li>\n<li><b>Gain<\/b><span>GN 105 dB &middot; the top of the published range<\/span><\/li>\n<li><b>Dynamic range<\/b><span>DR 80<\/span><\/li>\n<li><b>Processing<\/b><span>ENH 0 &middot; Compound OFF<\/span><\/li>\n<li><b>Output<\/b><span>MI 0.9 &middot; TIS 0.2<\/span><\/li>\n<li><b>Modes<\/b><span>B throughout &middot; B+M from 5:36 until M-mode is switched off inside the fourth point<\/span><\/li>\n<\/ul>\n<\/div>\n<\/div>\n<div class=\"sr-bl-dev__links\"><a href=\"https:\/\/suresultmed.com\/shop\/handheld-ultrasounds\/d3ultra-multipurpose-handheld-ultrasound\/\">D3Ultra specification and price &rarr;<\/a><a href=\"https:\/\/suresultmed.com\/specialty\/handheld-ultrasound-for-pulmonology\/\">Handheld ultrasound for pulmonology &rarr;<\/a><a href=\"https:\/\/suresultmed.com\/suresult-video-library\/\">Scan Library &rarr;<\/a><\/div>\n<\/div>\n<\/section>\n<section id=\"related\">\n<p class=\"sr-bl-krow\">Same device, other windows<\/p>\n<h2>Related scans<\/h2>\n<div class=\"sr-bl-rels\"><a class=\"sr-bl-rel\" href=\"https:\/\/suresultmed.com\/efast-exam-handheld-ultrasound\/\"><span class=\"sr-bl-rel__img\"><img decoding=\"async\" src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/efast-exam-right-upper-quadrant-poster.jpg\" alt=\"Right upper quadrant scan on a handheld ultrasound: liver and right kidney with the hepatorenal recess between them, Abdomen preset at 240 mm depth\" width=\"640\" height=\"360\" loading=\"lazy\"><span class=\"sr-bl-rel__len\">14:09<\/span><\/span><span class=\"sr-bl-rel__b\"><span class=\"sr-bl-rel__t\">eFAST trauma exam on the same handheld probe<\/span><span class=\"sr-bl-rel__d\">The thoracic windows of this lung survey inside a full trauma study \u2014 pericardium, both upper quadrants and the pelvis, in one pass.<\/span><span class=\"sr-bl-rel__cta\">Read the walkthrough &rarr;<\/span><\/span><\/a><a class=\"sr-bl-rel\" href=\"https:\/\/suresultmed.com\/suresult-video-library\/\"><span class=\"sr-bl-rel__img\"><img decoding=\"async\" src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/efast-related-dvt-three-point.jpg\" alt=\"Three-point compression DVT scan frame on a handheld linear probe showing a vein under compression\" width=\"640\" height=\"360\" loading=\"lazy\"><span class=\"sr-bl-rel__len\">1:23<\/span><\/span><span class=\"sr-bl-rel__b\"><span class=\"sr-bl-rel__t\">DVT: the three-point compression scan<\/span><span class=\"sr-bl-rel__d\">The scan to run when the lungs are normal and the patient is still breathless: common femoral, femoral and popliteal veins, compressed in sequence.<\/span><span class=\"sr-bl-rel__cta\">Watch in the Library &rarr;<\/span><\/span><\/a><a class=\"sr-bl-rel\" href=\"https:\/\/suresultmed.com\/suresult-video-library\/\"><span class=\"sr-bl-rel__img\"><img decoding=\"async\" src=\"https:\/\/suresultmed.com\/wp-content\/uploads\/efast-related-rib-fracture.jpg\" alt=\"High-frequency linear ultrasound frame of the rib cortex used to look for a cortical step-off\" width=\"640\" height=\"360\" loading=\"lazy\"><span class=\"sr-bl-rel__len\">6:42<\/span><\/span><span class=\"sr-bl-rel__b\"><span class=\"sr-bl-rel__t\">POCUS for rib fracture detection<\/span><span class=\"sr-bl-rel__d\">The other high-frequency chest-wall exam \u2014 a linear survey of the rib cortex, and what a cortical step-off looks like on screen.<\/span><span class=\"sr-bl-rel__cta\">Watch in the Library &rarr;<\/span><\/span><\/a><\/div>\n<p class=\"sr-bl-hublink\">All the clinical clips, filterable by anatomy and probe, are in the <a href=\"https:\/\/suresultmed.com\/suresult-video-library\/\">Scan Library<\/a>.<\/p>\n<\/section>\n<section id=\"faq\">\n<p class=\"sr-bl-krow\">Asked on this search<\/p>\n<h2>B-line questions<\/h2>\n<div class=\"sr-faq sr-bl-faq\">\n<details class=\"sr-bl-q\" open>\n<summary>What do B-lines on ultrasound mean?<\/summary>\n<p>B-lines mean fluid in the lung. They are vertical, laser-like reverberation artifacts that start at the pleural line, run to the bottom of the screen without fading, erase the A-lines they cross, and move with the breath. The conditions that increase them are the ones that put fluid or thickening into the interstitium: pulmonary oedema, pneumonia, ARDS and interstitial lung disease. In the walkthrough above they are called comet-tail artifacts, and the point is made that when enough of them appear they merge into one broad band. What I check first is simply whether they are there at all: their presence or absence at a window moves the differential further than their exact number does.<\/p>\n<p><span class=\"sr-bl-cite\">Source: <a href=\"https:\/\/www.pocus.org\/resources\/lung\/pocus-lung-introduction-to-a-lines-and-b-lines\" rel=\"nofollow noopener\" target=\"_blank\">POCUS Certification Academy \u2014 A-lines and B-lines<\/a>. Accessed September 5, 2026.<\/span><\/details>\n<details class=\"sr-bl-q\">\n<summary>What is the difference between A-lines and B-lines?<\/summary>\n<p>A-lines are horizontal and B-lines are vertical, and they mean opposite things. A-lines repeat below the pleural line at regular intervals because sound is bouncing between the probe and the pleura; they are what aerated lung looks like, which is why they appear in a healthy lung and in a pneumothorax alike and cannot settle the question on their own. B-lines rise from the pleural line and run down the screen, and they only exist where there is fluid in the lung. So A-lines plus lung sliding is a normal anterior scan; B-lines say the lung is wet at that window.<\/p>\n<p><span class=\"sr-bl-cite\">Source: <a href=\"https:\/\/www.pocus.org\/resources\/lung\/pocus-lung-introduction-to-a-lines-and-b-lines\" rel=\"nofollow noopener\" target=\"_blank\">POCUS Certification Academy \u2014 A-lines and B-lines<\/a>. Accessed September 5, 2026.<\/span><\/details>\n<details class=\"sr-bl-q\">\n<summary>How many B-lines are normal on ultrasound?<\/summary>\n<p>One or two in a single intercostal space can be normal, particularly at the lung bases and particularly in older patients. Three or more B-lines in one intercostal space is an abnormal finding and is read as interstitial syndrome at that window. The count is per space, not per patient, which is why the finding is recorded window by window rather than as a single verdict. My habit when teaching it is to count in one space, write the number down and move on: what you interpret is the pattern across the whole chest, never a single window on its own.<\/p>\n<p><span class=\"sr-bl-cite\">Source: <a href=\"https:\/\/www.pocus.org\/resources\/lung\/pocus-lung-introduction-to-a-lines-and-b-lines\" rel=\"nofollow noopener\" target=\"_blank\">POCUS Certification Academy \u2014 A-lines and B-lines<\/a>. Accessed September 5, 2026.<\/span><\/details>\n<details class=\"sr-bl-q\">\n<summary>How accurate is the BLUE protocol?<\/summary>\n<p>In the study that defined it, ultrasound profiles gave the correct diagnosis in 90.5% of 260 patients presenting with acute respiratory failure. Multiple anterior B-lines with lung sliding identified pulmonary oedema with 97% sensitivity and 95% specificity; the pneumonia profiles reached 89% and 94%; absent anterior sliding with A-lines and a lung point identified pneumothorax with 81% sensitivity and 100% specificity. That is the basis for the range quoted at 3:05 in the recording above.<\/p>\n<p><span class=\"sr-bl-cite\">Source: <a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC3734893\/\" rel=\"nofollow noopener\" target=\"_blank\">Lichtenstein DA, Mezi\u00e8re GA \u2014 Chest 2008, the BLUE protocol<\/a>. Accessed September 5, 2026.<\/span><\/details>\n<details class=\"sr-bl-q\">\n<summary>What is the lung point, and does this walkthrough show one?<\/summary>\n<p>The lung point is the spot on the chest wall where a partially collapsed lung meets the chest wall again, so sliding appears and disappears in the same image as the patient breathes. In the original BLUE protocol data it is the finding that took the pneumothorax profile to 100% specificity. It is not demonstrated in this recording: the subject\u2019s lungs are normal, sliding is present at every point scanned, and the recording is about recognising the normal picture well enough to know when it is missing.<\/p>\n<p><span class=\"sr-bl-cite\">Source: <a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC3734893\/\" rel=\"nofollow noopener\" target=\"_blank\">Lichtenstein DA, Mezi\u00e8re GA \u2014 Chest 2008, the BLUE protocol<\/a>. Accessed September 5, 2026.<\/span><\/details>\n<\/div>\n<\/section>\n<section id=\"sources\">\n<p class=\"sr-bl-krow\">Provenance<\/p>\n<h2>Sources<\/h2>\n<ul class=\"sr-bl-src\">\n<li><a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC3734893\/\" rel=\"nofollow noopener\" target=\"_blank\">Lichtenstein DA, Mezi\u00e8re GA \u2014 Chest 2008, the BLUE protocol<\/a><span>\u201cRelevance of lung ultrasound in the diagnosis of acute respiratory failure: the BLUE protocol.\u201d Chest 2008;134(1):117\u2013125. The three-point protocol, the ultrasound profiles, and the accuracy figures quoted on this page. Accessed September 5, 2026.<\/span><\/li>\n<li><a href=\"https:\/\/www.pocus.org\/resources\/lung\/pocus-lung-introduction-to-a-lines-and-b-lines\" rel=\"nofollow noopener\" target=\"_blank\">POCUS Certification Academy \u2014 A-lines and B-lines<\/a><span>Point-of-Care Ultrasound Certification Academy, Learning Library. Definitions of the pleural line, lung sliding, A-lines and B-lines, and the threshold at which B-lines become an abnormal finding. Accessed September 5, 2026.<\/span><\/li>\n<li><a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC8439137\/\" rel=\"nofollow noopener\" target=\"_blank\">Bhoil R et al. \u2014 Signs and lines in lung ultrasound<\/a><span>Journal of Ultrasonography 2021. Reference description of the lung ultrasound artifact set, including the seashore and barcode patterns in M-mode. Accessed September 5, 2026.<\/span><\/li>\n<li><a href=\"https:\/\/med.stanford.edu\/stanfordmedicine25\/the25\/lung-ultrasound.html\" rel=\"nofollow noopener\" target=\"_blank\">Stanford Medicine 25 \u2014 Lung Ultrasound<\/a><span>Stanford University School of Medicine. Teaching reference for the pleural line, A-lines, B-lines and the curtain sign at the lung base. Accessed September 5, 2026.<\/span><\/li>\n<li><a href=\"https:\/\/www.acep.org\/sonoguide\/basic\/lung\" rel=\"nofollow noopener\" target=\"_blank\">ACEP Sonoguide \u2014 Lung<\/a><span>American College of Emergency Physicians. Scanning technique and findings for the point-of-care lung examination. Accessed September 5, 2026.<\/span><\/li>\n<li><a href=\"https:\/\/suresultmed.com\/shop\/handheld-ultrasounds\/d3ultra-multipurpose-handheld-ultrasound\/\" rel=\"nofollow noopener\" target=\"_blank\">Suresult D3Ultra product page<\/a><span>The published attribute table for the device in this recording: the linear and convex frequency ranges, the four linear depth steps, the gain ceiling and dynamic-range steps quoted in the settings column above, and the imaging modes. Accessed September 5, 2026.<\/span><\/li>\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=tFsY4NcIBZA\" rel=\"nofollow noopener\" target=\"_blank\">Suresult channel \u2014 the video on this page<\/a><span>\u201cPOCUS Lung Exam Made Easy | BLUE Protocol with Suresult D3Ultra Handheld Ultrasound\u201d, published 12 October 2025. Duration 9:28. The transcript below is drawn from this recording. Accessed September 5, 2026.<\/span><\/li>\n<\/ul>\n<\/section>\n<div class=\"sr-final-cta\">\n<div>\n<h2>Which probe does your chest work actually need?<\/h2>\n<p>Lung ultrasound asks two opposite things of a probe. The pleura is a centimetre down and wants the highest frequency you have; an effusion at the base is ten centimetres down and wants the lowest. A three-in-one head covers both from one device, and a dedicated pair covers both better for more money. Tell us the ward and the case mix and you will get a direct recommendation in one conversation &mdash; one probe, two, or neither.<\/p>\n<\/div>\n<div class=\"sr-chat-link\">\n<button class=\"sr-crisp-consult-btn\" type=\"button\" data-sr-crisp-open onclick=\"window.$crisp=window.$crisp||[];window.$crisp.push(['do','chat:open']);\">ONLINE EXPERT CONSULT<\/button>\n<\/div>\n<\/div>\n<nav id=\"sr-bl-toc\" class=\"sr-light-toc sr-sticky-toc sr-article-toc\" data-suresult-toc data-sr-hide-on-wide-table aria-label=\"Lung walkthrough navigation\">\n<div class=\"sr-light-toc__head\">\n<div class=\"sr-light-toc__title\">On this page<\/div>\n<p><span class=\"sr-light-toc__progress\" id=\"sr-bl-progress\">0%<\/span><\/div>\n<div class=\"sr-light-toc__links\"><a href=\"#quick-answer\">Quick answer<\/a><a href=\"#four-points\">The four points<\/a><a href=\"#key-moments\">Key moments<\/a><a href=\"#what-it-shows\">What this scan shows<\/a><a href=\"#transcript\">Full transcript<\/a><a href=\"#device\">Device and settings<\/a><a href=\"#related\">Related scans<\/a><a href=\"#faq\">B-line questions<\/a><a href=\"#sources\">Sources<\/a><\/div>\n<p class=\"sr-light-toc__note\">Not sure which probe geometry your chest work actually needs?<\/p>\n<p><button class=\"sr-crisp-consult-btn\" type=\"button\" data-sr-crisp-open onclick=\"window.$crisp=window.$crisp||[];window.$crisp.push(['do','chat:open']);\">ONLINE EXPERT CONSULT<\/button><br \/>\n<\/nav>\n<\/div>\n<p><script>(function(){\nvar AMP=String.fromCharCode(38);\nvar VID='tFsY4NcIBZA';\nfunction embed(start){\nvar u='https:\/\/www.youtube-nocookie.com\/embed\/'+VID+'?rel=0'+AMP+'autoplay=1';\nif(start){u=u+AMP+'start='+start;}\nreturn u;\n}\nfunction mount(start){\nvar pl=document.getElementById('sr-bl-player');\nif(!pl){return null;}\nif(pl.classList.contains('is-live')){\nvar fr=pl.querySelector('iframe');\nif(fr){fr.src=embed(start);}\nreturn pl;\n}\nvar f=document.createElement('iframe');\nf.src=embed(start);\nf.title='Lung ultrasound on a handheld probe: the BLUE protocol walkthrough';\nf.allow='accelerometer;autoplay;clipboard-write;encrypted-media;gyroscope;picture-in-picture';\nf.setAttribute('allowfullscreen','');\npl.innerHTML='';\npl.appendChild(f);\npl.classList.add('is-live');\nreturn pl;\n}\nvar p0=document.getElementById('sr-bl-player');\nif(p0){p0.addEventListener('click',function(){mount(0);});}\nvar tx=document.getElementById('sr-bl-transcript');\nif(tx){\nif(window.matchMedia('(max-width:768px)').matches){tx.removeAttribute('open');}\n}\ndocument.addEventListener('click',function(e){\nvar t0=e.target;\nif(!t0){return;}\nif(!t0.closest){return;}\nvar a=t0.closest('[data-sr-seek]');\nif(!a){return;}\ne.preventDefault();\nvar pl=mount(a.getAttribute('data-sr-seek'));\nif(pl){pl.scrollIntoView({behavior:'smooth',block:'start'});}\n});\nvar toc=document.getElementById('sr-bl-toc');\nif(toc){\nvar 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v=m>0?Math.round(h.scrollTop\/m*100):0;\nif(pr){pr.textContent=v+'%';}\n}\nwindow.addEventListener('scroll',function(){\nif(tick){return;}\ntick=true;\nrequestAnimationFrame(upd);\n},{passive:true});\nupd();\n})();<\/script><br \/>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/suresultmed.com\/b-lines-lung-ultrasound-blue-protocol\/#article\",\"headline\":\"B-Lines on Lung Ultrasound: the 9-Minute D3Ultra BLUE Protocol Walkthrough\",\"description\":\"A four-point lung ultrasound survey run as a bedside protocol on a handheld probe: A-lines, B-lines, pleural sliding, the seashore and barcode signs in M-mode, and the curtain sign at the lung base \u2014 with timestamped key moments, the full transcript, and the preset, depth, gain and frequency read off the device interface.\",\"datePublished\":\"2026-09-05\",\"dateModified\":\"2026-09-05\",\"inLanguage\":\"en-US\",\"mainEntityOfPage\":{\"@type\":\"WebPage\",\"@id\":\"https:\/\/suresultmed.com\/b-lines-lung-ultrasound-blue-protocol\/\"},\"image\":\"https:\/\/suresultmed.com\/wp-content\/uploads\/b-lines-lung-ultrasound-blue-protocol-cover.jpg\",\"author\":[{\"@type\":\"Person\",\"@id\":\"https:\/\/suresultmed.com\/#fernando-mariz-md\",\"name\":\"Fernando Mariz, MD\",\"jobTitle\":\"Gynecology and pelvic surgery physician\",\"url\":\"https:\/\/suresultmed.com\/author\/dr-fernando-mariz-md\/\",\"knowsAbout\":[\"Gynecology\",\"Pelvic surgery\",\"Sonography\",\"Point-of-care ultrasound\"]},{\"@type\":\"Person\",\"@id\":\"https:\/\/suresultmed.com\/#jailyn-avila-md\",\"name\":\"Jailyn Avila, MD\",\"jobTitle\":\"Emergency medicine physician and POCUS educator\",\"knowsAbout\":[\"Emergency medicine\",\"Point-of-care ultrasound\",\"Residency 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A-lines, B-lines, comet tails, and the seashore and barcode signs in M-mode.\",\"thumbnailUrl\":[\"https:\/\/suresultmed.com\/wp-content\/uploads\/lung-ultrasound-pleural-line-m-mode-poster.jpg\"],\"uploadDate\":\"2025-10-12\",\"duration\":\"PT9M28S\",\"embedUrl\":\"https:\/\/www.youtube-nocookie.com\/embed\/tFsY4NcIBZA\",\"isFamilyFriendly\":true,\"inLanguage\":\"en\",\"publisher\":{\"@type\":\"Organization\",\"@id\":\"https:\/\/suresultmed.com\/#organization\",\"name\":\"Suresult\",\"url\":\"https:\/\/suresultmed.com\/\"},\"mainEntityOfPage\":{\"@id\":\"https:\/\/suresultmed.com\/b-lines-lung-ultrasound-blue-protocol\/\"},\"transcript\":\"[The presenting clinician introduces himself.] Today we're going to do a very, very quick sample lung scan using a Suresult D3Ultra handheld ultrasound unit. My version of the exam uses four points. Why do I pick four points? If you look at the lobes, I get this lobe, this lobe, this lobe, and then I pick the bottom corner where fluid is likely to collect. There are many similar protocols. The BLUE protocol uses three points instead of four points, and in general the more points you do, the better. So if you want, you can do the posterior wall; and if you don't like three, you can pick four, five, six \u2014 you can check between every rib if you want. Here, just on myself, I wanted some samples of normals to talk about what we are looking for. We're looking for pleural sliding \u2014 it sort of looks like ants moving along the wall of the cavity. If it's not moving along the wall of the cavity, guess what: you have a pneumothorax. The lung isn't there, or the lung isn't moving. In general, the rest of the appearance of the lung \u2014 you don't really see into the lung, because the lung is full of air. So pneumothorax and regular normal lung look the same. When you get past the pleura you do see something they call an A-line, which is just a reverberation artifact: sound bouncing back and forth here makes this line repeat itself at regular intervals. That is a sign that's either pneumothorax or normal lung. And then you look for pleural sliding, and if you see pleural sliding you can rule out pneumothorax. Some people like to use M-mode and they look for the seashore sign \u2014 this looks like a sandy beach and this looks like the water, and that's what you should see. And if you see something more that looks like this, like just a barcode, then that's a sign of a pneumothorax. And again, just check different locations; we see the same thing. We're looking for ants crawling across the pleura. And here at that corner, this is called curtain sign, because you can't see through lungs normally, right? So what we're seeing is the lung basically move, and it's covering up \u2014 it prevents us from seeing within the liver. If there was fluid we would see a corner of hypoechoic or anechoic fluid, sort of a triangle right here. And if the lungs had pneumonia, were full and solid, we'd be able to see through the lungs. So here's just an example of what an effusion would look like. Here's another case where we have consolidation, so we can basically see through the lungs \u2014 we can see the spleen or liver, depending on what side of the body you're on. This reverberation artifact is considered normal or pneumothorax. If you get something called B-lines or comet-tail artifacts, that means the lungs are wet; it increases your suspicion for pneumonia. And if you get something that looks like this \u2014 basically these lines, there's so many of them that they sort of bunch up into just one giant line \u2014 that is also very indicative of pneumonia. I mentioned there's lots of protocols; the BLUE protocol is quite common. And you can see for the BLUE protocol you get sensitivities and specificities, you know, 80s, 90s. So it's pretty good. [Promotional segment omitted, 3:17\u20133:36.] So my protocol for the lung exam is basically the BLUE protocol, and the B in BLUE stands for bed, or bedside. So basically if someone's lying down, you only have access to the front and maybe a bit of the side, and that's it. If you have access \u2014 let's say if they're sitting like this \u2014 well, you have access to the back. In fact you have easier access to the back than the front, so you can add on more points. Or let's say you have a woman, and there are breasts and bras in the way: you can still check a lot of the lung from the back instead of the front. And if you're looking for something like pneumonia or consolidation, you're going to see that on the back as well as the front, so don't worry about missing the two front parts when you have access to the back. The reason why this is my recommended protocol is because it's just a few points, and the BLUE protocol is a validated set of points to check. So if I follow that, that means your exam is at least as good as the BLUE protocol, which is, you know, 80 to 90-some percent accurate at finding things like pneumonia and pneumothorax. And that raises another point. Based on your clinical intuition \u2014 what exactly are you looking for? You might be looking for different things in the images. If you're looking for pneumonia, then you don't really care about the pleura sliding around; you just care about those B-lines or the C-lines. If you care about a pneumothorax, then you're really looking at that pleura and you're just going point to point, really focusing on that pleura. Again, if you have time, I guess you can always look at everything, but you want to answer your clinical question. Is there pneumothorax? If that's your only clinical question, then you're just looking: is the pleura sliding, are there A-lines \u2014 A-lines for a pneumothorax or for a normal lung. And if you find nothing, if you follow that BLUE protocol and you find nothing, normal lung \u2014 and they have lung symptoms \u2014 well, maybe check for a DVT. Maybe it's a pulmonary embolism, in which case the lung scan shows normal but they still have trouble breathing. So I'm going to turn on M-mode, because some people like M-mode for looking for seashore sign versus barcode sign. I don't really pay attention to that myself; I'm just going to be looking at the pleura, looking for those ants moving across. I'm looking for: are they A-lines, B-lines or C-lines. So around second rib, let's take a look here. So between the ribs, and take a breath. And we can see we have an A-line here. We're not getting comet-tail type artifacts like B-lines, so we have basically an A-line, and we do get a little bit of motion across, and we do get more of a seashore sign instead of the barcode sign. And let's go to the next point. So normally around, I don't know, like fifth, sixth rib. Now this one I can really, really see it. The first one, honestly, I didn't see the pleural sliding that clearly; this one you can really see the pleural sliding here. Remember, if you can see the pleura sliding, that rules out \u2014 virtually 100% rules out \u2014 a pneumothorax, because you can't have pleural sliding if the lung isn't attached to the wall of the thoracic cavity. So if you're missing pleural sliding, well, it could be other things; but if you have pleural sliding that rules out pneumothorax. So we have pleural sliding, so I definitely don't have pneumothorax. So I added more gel, and the next point is over here. And again, we can very clearly see pleural sliding. So that's great. And again we're not seeing these B-lines or anything that looks like that, so no pneumonia for me. And if I move down, now this is posterolateral, inferior. I go down until I hit the bottom of the lungs. In fact, I'm going to turn off M-mode now. Okay, so what are we looking at? Well, particularly if we can go through a few frames here, we have the liver here, and we have \u2014 we have rib, we have liver, and we have the lung. This is called the curtain sign. The lung is covering, because we can't see through a lung, so it's covering the liver; and as I breathe the lung is \u2014 well, the diaphragm is moving up and down, and so the lung is moving, and so we see this curtain come across the liver and prevent us from seeing anything. So this is normal. If we can see through the lungs, that's bad. That means there's consolidation and the lungs are full of fluid and junk. If there is a large hypoechoic or anechoic collection of fluid here \u2014 here we see it's often just this triangle, black triangle \u2014 then we would have a lung effusion, which could be a hemothorax, for example. And that's it. Pretty quick. 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They are vertical, laser-like reverberation artifacts that start at the pleural line, run to the bottom of the screen without fading, erase the A-lines they cross, and move with the breath. The conditions that increase them are the ones that put fluid or thickening into the interstitium: pulmonary oedema, pneumonia, ARDS and interstitial lung disease. In the walkthrough above they are called comet-tail artifacts, and the point is made that when enough of them appear they merge into one broad band. What I check first is simply whether they are there at all: their presence or absence at a window moves the differential further than their exact number does.\"}},{\"@type\":\"Question\",\"name\":\"What is the difference between A-lines and B-lines?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A-lines are horizontal and B-lines are vertical, and they mean opposite things. A-lines repeat below the pleural line at regular intervals because sound is bouncing between the probe and the pleura; they are what aerated lung looks like, which is why they appear in a healthy lung and in a pneumothorax alike and cannot settle the question on their own. B-lines rise from the pleural line and run down the screen, and they only exist where there is fluid in the lung. So A-lines plus lung sliding is a normal anterior scan; B-lines say the lung is wet at that window.\"}},{\"@type\":\"Question\",\"name\":\"How many B-lines are normal on ultrasound?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"One or two in a single intercostal space can be normal, particularly at the lung bases and particularly in older patients. Three or more B-lines in one intercostal space is an abnormal finding and is read as interstitial syndrome at that window. The count is per space, not per patient, which is why the finding is recorded window by window rather than as a single verdict. My habit when teaching it is to count in one space, write the number down and move on: what you interpret is the pattern across the whole chest, never a single window on its own.\"}},{\"@type\":\"Question\",\"name\":\"How accurate is the BLUE protocol?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"In the study that defined it, ultrasound profiles gave the correct diagnosis in 90.5% of 260 patients presenting with acute respiratory failure. Multiple anterior B-lines with lung sliding identified pulmonary oedema with 97% sensitivity and 95% specificity; the pneumonia profiles reached 89% and 94%; absent anterior sliding with A-lines and a lung point identified pneumothorax with 81% sensitivity and 100% specificity. That is the basis for the range quoted at 3:05 in the recording above.\"}},{\"@type\":\"Question\",\"name\":\"What is the lung point, and does this walkthrough show one?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The lung point is the spot on the chest wall where a partially collapsed lung meets the chest wall again, so sliding appears and disappears in the same image as the patient breathes. In the original BLUE protocol data it is the finding that took the pneumothorax profile to 100% specificity. It is not demonstrated in this recording: the subject\u2019s lungs are normal, sliding is present at every point scanned, and the recording is about recognising the normal picture well enough to know when it is missing.\"}}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/suresultmed.com\/b-lines-lung-ultrasound-blue-protocol\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/suresultmed.com\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Scan Library\",\"item\":\"https:\/\/suresultmed.com\/suresult-video-library\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"B-lines on lung ultrasound: the BLUE protocol walkthrough\",\"item\":\"https:\/\/suresultmed.com\/b-lines-lung-ultrasound-blue-protocol\/\"}]}]}<\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A four-point lung survey run end to end on a handheld probe &mdash; pleural sliding, A-lines, B-lines and the curtain<\/p>","protected":false},"author":1,"featured_media":35801,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_titles_title":"B-Lines on Lung Ultrasound: BLUE Protocol Walkthrough","_seopress_titles_desc":"A-lines, B-lines, the seashore sign and the curtain sign, point by point on a handheld probe \u2014 with timestamps, on-screen settings and the transcript.","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"https:\/\/suresultmed.com\/wp-content\/uploads\/b-lines-lung-ultrasound-blue-protocol-cover.jpg","_seopress_social_fb_img_attachment_id":35801,"_seopress_social_fb_img_width":1600,"_seopress_social_fb_img_height":900,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"https:\/\/suresultmed.com\/wp-content\/uploads\/b-lines-lung-ultrasound-blue-protocol-cover.jpg","_seopress_social_twitter_img_attachment_id":35801,"_seopress_social_twitter_img_width":1600,"_seopress_social_twitter_img_height":900,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"footnotes":""},"categories":[457],"tags":[],"class_list":["post-35804","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-scan-library"],"acf":[],"_links":{"self":[{"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/posts\/35804","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/comments?post=35804"}],"version-history":[{"count":5,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/posts\/35804\/revisions"}],"predecessor-version":[{"id":35850,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/posts\/35804\/revisions\/35850"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/media\/35801"}],"wp:attachment":[{"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/media?parent=35804"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/categories?post=35804"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/suresultmed.com\/it\/wp-json\/wp\/v2\/tags?post=35804"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}