Just when you thought your brain could unwind on a Friday, you realise that it would rather be challenged with some good old fashioned medical trivia FFFF…introducing Funtabulously Frivolous Friday Five178.
You finally manage for the first time in the year to make it to the doctors lounge and find the surgical team playing computer games. You roll your eyes and mutter something derogatory under your breath. The surgical team state that they are training. Do video games actually help surgeons?
Plaster is the common name for calcium sulphate hemi hydrate made by heating the mineral gypsum. Plaster was first made about 9000 years ago, but it wasn’t used on a large scale until 1700s, when it was required to be used in on all buildings in Paris post the 1666 fire of London.
This resulted in large-scale mining of gypsum which was available around Paris in huge quantities (namely Montmartre). Thus, during the early 18th century, Paris became the centre of plaster production, and hence the name, Plaster of Paris. [Reference]
After Valentine’s day you meet up with friends and discuss what you did. You claim you scaled a wall to sing to your sweetheart and subsequent sustained a ‘lover’s fracture’, what is this and what is the associated injury?
This is an 84 year old male, who presents to the ED with multiple complaints, including shortness of breath. A bedside ultrasound was performed and the lungs were evaluated.
Small Pleural Effusion. You can see the spine ABOVE the diaphragm (this is to the left on the screen), and some anechoic fluid (black) which is the fluid.
This image is taken with the curvilinear probe in the RUQ, in a coronal plane, with the probe marker pointed to the patient’s head. This is the same location where we place the probe in a FAST exam, to evaluate Morrison’s pouch. Place the probe at the level of the xiphoid process in the mid-axillary line. Consider obliquing slightly so that the probe is parallel to the ribs and you decrease the amount of interference from rib shadow. Remember, if you are doing a FAST there are 4 areas you need to investigate in the RUQ: 1) Morrison’s pouch 2) tip of the liver/inferior pole of the kidney 3) under the diaphragm and 4) over the diaphragm. When evaluating for a pleural effusion, we just look above the diaphragm.
Normally, the lung is filled with air. Air does not transmit the ultrasound beam well, so you cannot visualize the spine in the chest. It is normal to see the spine below the diaphragm (in the abdomen), but we are normally not able to visualize the spine above the diaphragm through normal lung. If you do visualize the spine above the diaphragm, there is something abnormal in or around the lung, i.e. NOT air, that is allowing the ultrasound beam to travel all the way to the spine. Often times, this is caused by a pleural effusion, which can be seen as anechoic (black) fluid above the diaphragm. Fluid, in contrast to air, allows for easy transmission of the ultrasound wave, enabling visualization of the spine in the chest. This is ABNORMAL and is referred to as the Spine Sign.
The spine sign on ultrasound was found to have a sensitivity of nearly 74% and specificity of 93% for identifying a pleural effusion. This is superior to chest x-ray, which has only sensitivity of 69% and specificity of 54% as compared to gold standard CT scan.
This is a 71-year-old male with a complicated past medical history, who presents to the ED as a transfer from an outside hospital after ROSC following PEA arrest. Patient had a femoral line placed at the outside hospital prior to transfer. There was some concern about whether the line was in the artery or in the vein, so the ultrasound team was called in to help.
Correct placement of line in femoral vein. This is a parasternal long view, and you can see the right ventricle is the most anterior chamber of the heart. We have injected saline, and are able to see bubbles in the RV, confirming placement of the line in the femoral vein.
**Please note, limited views were obtained on this patient, so the findings on the ultrasound are subtle. Please see the 5-minute sono podcast below for another, more obvious, example of this. You can watch the whole video (only 5 minutes) or you can fast forward to minute 2 and just see the bubbles
Ultrasound can be used for rapid central venous catheter placement confirmation by visualizing bubble artifact in the right side of the heart. To do this, inject agitated saline into the CVC. At the same time, place your cardiac probe on the patient's chest and obtain a view of the heart. As you rapidly inject the agitated saline through the central line, watch for artifact from the bubbles in the right heart. If you see “bubbles” in the right side of the heart, you know that your CVC must be in the right place!
The Bubble Study: Ultrasound confirmation of central venous catheter placement. Am J Emerg Med. 2015 Mar;33(3):315-9.
This is a 41 year old female who presents with left lower abdominal, back pain, and vaginal bleeding for 5 hours. The patient has had no prior pregnancies and no history of STIs. The patient had a positive pregnancy test in the ED.
This patient has evidence of a gestational sac outside of the uterus on the bedside ultrasound. There is no clear fetal pole is visualized. A small amount of free fluid can be seen in the cul de sac. This patient's bHCG was 2500.
Any patient with a positive pregnancy test and abdominal pain or vaginal bleeding should be evaluated for an ectopic pregnancy. On a bedside ultrasound, a gestational sac alone is not adequate for diagnosis of IUP. In addition, you need to see either a yolk sac or a fetal pole. A gestational sac can be visualized as early as 4 weeks gestation. At about 5 weeks you may begin to see a yolk sac as well. If located in the endometrium, this is adequate to rule in an IUP. In patients undergoing fertility treatment, make sure you consider a heterotopic pregnancy as well.
This patient was transferred to an outside hospital specializing in Ob/Gyn care for further management of this ectopic pregnancy. She ultimately went to the OR and was found to have a ruptured ectopic pregnancy.
The Azurion system builds on Philips’ many decades of imaging expertise combined with a growing integrated therapy portfolio, enhanced by the 2015 acquisition of Volcano. It is is expected to form the core of Philips’ integrated image-guided systems including vascular surgery, cardiology, oncology, and neuroradiology. The new imaging platform is underpinned by Philips’ redesigned operating system, ConnectOS, which features a new user interface focused on prioritizing ease-of-use and maximizing control from multiple locations in the interventional suite.
Azurion minimizes preparation time and error by allowing routine tasks to be pre-programmed into the system with individual user preferences. The system also allows a team of clinicians to work in parallel, reducing procedure times and improving patient outcomes for both large volumes of routine cases and more complex advanced procedures.
Azurion also features substantial hardware upgrades compared with previous system releases, with over 1,000 new components installed, including an improved flat-panel detector. Together these combine to deliver real-time image processing and high-quality imaging with a low X-ray dose.
In the new system Philips has prioritized the seamless integration of vital procedural information in real-time. Updates from imaging systems, navigation tools, interventional devices, and patient records may be accessed throughout the interventional lab.
Development of the Azurion system at Philips occurred in conjunction with a large number of leading clinicians and clinical strategic partnerships. The drive to deliver benefits for both patients and care providers has resulted in a system that incorporates ergonomic design combined with new performance and productivity dashboards. These features help clinicians provide improved care and bring the benefits of image-guided therapies to more patients worldwide.
“With this solution, Philips provides us with advanced technologies and an excellent user experience, combined with services for guaranteed uptime, seamless integration into our hospital workflows, staff training and education, and enhancement of our productivity. This enables our staff to fully focus on what they do best – providing superior care to our patients,” in a statement said Aki Haukilahti, Executive Vice President and CFO of Heart Hospital, Tampere University Hospital, Finland.
Here’s a Philips promo video showing off the Azurion:
“Education is the most powerful weapon which you can use to change the world” -Nelson Mandela The time is ripe for me to deepen my understanding of the sociopolitical environment in which I practice. Confession: I am a news junkie… Continue Reading →
Great discussion of an interesting ECG. Let’s talk blocks!
As you recall, the electricity in a well-functioning heart marches orderly from the SA node through the gap junctions of cardiac myocytes into the AV node and down the Bundles of His into the Left and Right Bundles. And if you’re really astute, you may even divide the Bundles into Fascicles, the Right Bundle as one and the Left Bundle as two, an Anterior and Posterior branch
Just like pre-school, let’s start stacking, it’s easy at first, but basics let you build skyscrapers (it is New York…) Prior to the bundles and fascicles, there are degrees of AV Block (slow conduction in the AV node). First Degree is just “longer than a big block on the ECG” (PR > 200 milliseconds). Second Degree is when “da beat drops” and has two flavors, Mobitz I and II. One flavor “winks back at you” before it drops (Mobitz I, Wenckebach, PR prolongation prior to non-conducted QRS) and the other “drops whenever” (Mobitz II, non-conducted QRS without PR prolongation). Lastly, Third Degree block occurs when communication between Atria and Ventricles breaks down and they “do their own thing” (AV dissociation).
Our friend, William Marrow, taught us early in medical school that if the Right Bundle is blocked, the QRS will be prolonged (>120 msec) with a “bunny ear pattern” in V1 or V2 (rSR, rsR or RR) and a “dip” in V6 (Terminal S Wave). And that Orange Book in the library said if the Left Bundle is blocked, the QRS will be prolonged (>120 msec) with “a dip” in V1 (QS or rS) and an “up down” in V6 (slurred R wave) with no “dips in the V’s” (absent septal Q waves in precordial leads).
Once we got fancy, we realized the Left Bundle split into two branches, an Anterior and a Posterior. Dubin said that when these fascicles were blocked, we’d see “little dips in front of the tall thing” (LAFB: rS in II, III, aVF and qR in I, aVL vs. LPFB: qR in III, aVF and rS in I) and “a quick axis check” would tell us which was which (LAFB: LAD vs. LPFB: RAD).
What if more than one of the three fascicles is blocked (RBBB, LAFB, LPFB) at the same time? This could lead to a Bifascicular Block (2 Fascicles) or a Trifascicular Block (3 Fascicles). If all three of these fascicles are blocked (Complete Heart Block) no signals from the atria reach the ventricles (AV dissociation) and the ventricular myocytes pace themselves very slowly (Ventricular Escape Rhythms). Until you place a pacemaker, this can lead to decreased perfusion in key organs (e.g. the brain, causing syncope) – a clearly dangerous situation.
A Brief History Break (The Original Kings of County)
Before Hipsters roamed Brooklyn and beards ruled the land, Dutch anatomist, Karl Frederik Wenckebach was sporting a killer moustache in medical wards in the Netherlands. He studied the heart’s communication system, and the tract that connects the SA and AV node
(Wenckebach’s bundle) bears his namesake. Interestingly enough, his father is credited with developing the Netherland’s first telegraph. Let’s just say the family communicated well. Heart touching, really
Bifascicular Block is relatively straightforward. It’s a block in either the (1) Right Bundle and Left Anterior Fascicle, (2) Right Bundle and Left Posterior Fascicle or (3) in the Left Anterior and Left Posterior Fascicle. Interestingly, if both fascicles of the Left Bundle are blocked, the ECG would show a Left Bundle Branch Block, meaning one can think of this block as a type of Bifascicular block (though in some cases the block may occur in the Bundle above the fascicles). In Bifascicular Block, there is still a pathway for the atria to communicate with the ventricles. Clinically, this means Cardiology can see the patient on an outpatient basis and emergent pacemaker is not always indicated.
Which leads us to…
Trifascicular Block indicates a conduction problem in the Right Bundle as well as the Left Bundle or both of its fascicles. It comes in two flavors: Definite (all three fascicles contain disease) and Possible (all three fascicles likely contain disease).
Definite Trifascicular Block exists in three cases:
1) If the ECG shows a Left Bundle (2 fascicles) at one moment and a Right Bundle (1 fascicle) the next, then all three fascicles must have disease
2) If the ECG always show a Right Bundle (1 fascicle) but alternates between a Left Anterior and Left Posterior Fascicular Block (2 fascicles), all three fascicles must have disease
3) Mobitz II blocks usually occur past the Bundle of His in the fascicles, so if this exists (1 fascicle) with a Left Bundle Branch Block (2 fascicles), all three fascicles are definitely diseased.
Possible Trifascicular Block exists in two cases:
1) Mobitz I (and 1st Degree AVB) may occur before the Bundle of His (0 fascicles) or past it (1 fascicle), if either of these exist with a Bifascicular Block (2 fascicles), it is possible all three fascicles are diseased
2) Complete AV Block exists in many ways (in the AV node itself, in the bundles below it, or in the fascicles below those) and can be categorized as possible Trifascicular Block.
What About Our Patient?
Armed with our new understanding of blocks, we see that this ECG shows a Right Bundle Branch Block, a Block in the Left Anterior Fascicle as well as a Mobitz I (Wenckebach). Since Mobitz I may occur past the Bundle of His (in this case possibly in the Left Posterior Fascicle), this can be classified as a Possible Trifascicular Block. Given the risk of complete AV block (and resultant escape bradydysrhythmias or possible triggered tachydysrhythmias), cardiology consultation for pacemaker placement is warranted.
The Clinical Monster on this case did just that and our patient is happily walking around Brooklyn, pacemaker in place.