6 Spleen - Final Edit
[00:00:00] Okay. Welcome back to behind the knife ab site review. Today we're covering spleen. So, let's john, let's jump right in with some anatomy and physiology. So what are the main ligaments? There, there are some minor ligaments, but what are the most surgically important ligaments attachments to the spleen?
Yep. This is, these are all what hold the spleen up into the splenic, which contains your short gastric. Your spleen, renal ligament. It contains your splenic vessels and then in the tail of the pancreas and you, your splenic colic and your slen phrenic ligaments. Yep. Great. So gastro, splenic, slen, renal spleen, colic, slen, phrenic.
Those are your attachments. And you mentioned some things that, that run in there that are important. Kevin, blood supply to the spleen. Yeah, so it's pretty straightforward. You've got your splenic artery, which is a, has a very tortuous course and runs on the superior aspect of the pancreas. And then you have your splenic vein, which runs posterior to the pancreas, which is important for some conditions we'll discuss.
And then you also have your short gastric. So even with a splenic artery [00:01:00] embolization, you can actually still have function of your spleen from these short gastrics that feed the spleen also. Great. Okay. John, what does the spleen do? What are the spleen functions? So it has many functions including storing platelets.
Filters, erythrocytes, reenergizes, erythrocytes to pitting immune function. It's the lar largest concentration of lymphoid tissue in the body. And just a reminder, pitting is removal of intercellular products from the erythrocytes, and then you have opsonization include tuftin and proper.
There are key proteins in this process. Yeah, right. Yeah, I don't know why that's important, but it shows up every once in a while. The testin and properitin, these are the proteins involved in the optimization process of the spleen. So just one of those rogue memorization things that you have to do. Kevin, we talked about this when we break it up into red and white pulp.
What do we mean by that and what are the different functions of those those different structures? Yeah, thankfully it actually kind of makes sense, at least for my simple brain. The red pulp filters the RBCs, the white [00:02:00] pulp does the immune functions. So John, you're a trauma surgeon, you take out a lot of spleens what would you see on a peripheral blood smear after you take out one of your patient's spleen?
What might you see on a peripheral blood smear? Yeah, I can, you can get these from either an absent spleen or a damaged spleen that's not functioning. There's a few that are, that used to be tested more on the outside when it was focused on basic sciences, but occasionally they still show up. So you have your Howell Jolly bodies which are nuclear remnants and this is the most reliable finding.
You'll usually see it with an absence spleen. You have your Papperheimer bodies, which are iron deposits. You can have target cells which are immature red blood cells. Heinz bodies, which are intracellular denatured hemoglobin. Spur cells, which is a deformed membrane of the RBC. And Jason, what if I definitively, personally took out the spleen, and I don't see any of these in the peripheral blood smear?
Yeah, I think that's actually what you're going to see on the outside. If you see, if you see this show up in a question at all, you're going to have a patient that was, had a splenectomy [00:03:00] for whatever reason, and then they have a normal peripheral blood smear, and you don't see these. And what you have to think about is that there's an accessory spleen.
So Kevin, what are some indications for splenectomy? I mean, we kind of covered, you know, we know John takes them out in the setting of trauma, so unstable trauma patients, but what are other indications for splenectomy? Yeah, there are some hematologic disorders such as ITP and serocytosis. Some patients can have a splenic abscess.
Sometimes there's some symptomatic cysts within the spleen. And then there are some primary malignancies, mainly non Hodgkin's lymphomas. Okay. So, so John splenic trauma, you know, we talk about splenic spleen trauma pretty extensively in the, in the trauma chapter, but you can you just briefly take us through some principles of managing splenic trauma.
Yeah. Splenic trauma can also be secondary to iatrogenic trauma. Most commonly you'll see this is during foregut operations or colon procedures. We have excessive attraction on the ligaments. But the generalization, if you have splenic trauma such as penetrating trauma. You're going [00:04:00] to perform a splenectomy.
Blunt injury of the spleen does have options for selective non operative management. These patients had to be hemodynamically stable without peritonitis. Otherwise, they will get some splenectomy. Non operative management of splenic trauma includes observation in hospital or the ICU depending on how they're doing.
Serial abdominal examinations, serial hematocrit measurements, and sometimes a period of immobility in some institutional protocols. You also consider angiogra angiography intervention for splenic injuries that most likely have some torpor contrast blush. You can do this, there's a lot of different scales you can use, but to determine whether a patient is a good candidate for angiography intervention.
But typically this is a conversation for your IR colleagues, but once again the patient has to be. He may actually stable without peritonitis. Okay, great. And be sure to listen to the trauma episode and review the trauma chapter. We do, we talk a little bit more extensively about splinting trauma, but moving on, Kevin you mentioned some hematologic disorders.
[00:05:00] So how about idiopathic thrombocytopenia? Purpura ITP. What, what's the etiology? What's the cause behind this? Yeah, this glycoprotein 2b, 3a
and 1a, 2a. Okay. And yeah, this is a diagnosis of exclusion. So we need to rule out other causes of thrombocytopenia. What's the initial management? Yeah, generally steroids and IVIG can help manage this. Sure. And then splenectomy is for medically refractory cases or for recurrence. And you can avoid the need to have patients on longstanding steroids because that's obviously not a good idea if you can avoid it.
A good response to steroids does portend a generally favorable response after splenectomy. When it, so let's say you're taking a patient, they've, they've been on IVIG. And steroids, they had a good response, but they have a recurrence. They relapse and you're preparing to take them for, for surgery.
The platelets are [00:06:00] 50. When would you transfuse those platelets? It can be tempting to transfuse these patients before going to the operating room, but with this condition, you actually need to wait. unless they have intraoperative bleeding. Yeah. So you're typically only transfused for if you're having intraoperative bleeding and when you intraoperatively, you should give those platelets after ligating the splenic artery.
Cause that will help prevent those consumption of those transfused platelets. Okay. How about hereditary spherocytosis? That's one of the more common hematologic disorders. How do they present? So, hereditary serospitosis usually presents with anemia and splenomegaly. That's an autosomal dominant defect in the cell membrane protein spectrum which leads to RBCs that are less deformable, which then be called by the spleen.
Splenectomy is recommended for symptomatic patients older than 6 years old. Because you want them to develop an immune function prior to splenectomy. Yeah, great. Awesome. So yeah, hereditary spirocytosis, you got that spectrum protein that'll show up every once in a [00:07:00] while present with the anemia.
Splenectomy after the age of six for symptomatic patients. Now, John, there's something you need to consider at the time of splenectomy in these patients and it's an additional procedure. What am I getting at there? Yeah, sometimes you have to add on a cholecystectomy at the time of surgery. You want to check for gall stones because the massive amount of hemolysis may produce bilirubin stones.
Yeah. So they're very common for these patients to have bilirubin stones. So you get a right upper quadrant ultrasound and you may want to perform a cholecystectomy at the time as well. Kevin, back to you. So pyruvate kinase deficiency what is that? Yeah, this is a congenital hemolytic anemia caused by impaired glucose metabolism.
And what's the role of splenectomy in these patients? Yeah, it actually helps prevent transfusion requirements. Yeah, so these patients can have anemia episodes that are triggered by infection, fava beans, funnily enough anti malarials, and certain antibiotics [00:08:00] like sulfas and nitrofurantoin. There are some other hemoglobinopathies, like sickle cell, thalassemias, that are additionally rare indications for splenectomies.
Those are not going to show up on the ab site, but something that might is a splenic abscess. So, who gets splenic abscesses John? Yeah, the most common cause for this is IV drug use. They often get it from endocarditis. And secondary infections from a traumatic pseudocyst and also patients with sickle cell disease.
Yeah, so these are typically diagnosed on CT scan. And there are some CT characteristics that are important for management. So how do we manage these, John? So patients with a unilocular... Abscess with a thick wall and they're stable can undergo percutaneous drainage patients with multilocular thin walled abscesses.
You have to be suspect a kind of cockle abscesses and then you may need to perform a spondectomy. Okay, great. Okay. So, yeah, spondic abscess on the upside, if it's unilocular, thick walled. [00:09:00] Precutaneous drainage for those multi loculated splenectomy. And that does show up and is frequently tested. So not, let's talk not more about abscesses but let's talk about splenic cyst.
So what does a splenic cyst look like, Kevin? Yeah, so this is a well defined but hypodense lesion without an enhancing ring. Okay, and sometimes we talk about true cysts versus false cysts. What's the distinction there? Yeah, so the true cysts are the ones that are either congenital or parasitic or neoplastic, whereas the false cysts are generally post traumatic pseudocysts.
Yeah, so sometimes you'll see somebody who's got a history of blunt trauma that will show up with a a splenic cyst. What do we do about them? So, if they're asymptomatic, we leave them alone. Serology and imaging characteristics can typically rule out parasitic cysts or malignancy. Okay, what about large cysts or if they're symptomatic?
Generally, if they're greater than 5 centimeters or symptomatic, you can consider a laparoscopic [00:10:00] cyst excision or fenestration. Perfect, okay. John, what's a very common thing that we'll see is a splenic hemangioma? Yeah, that's your most common splenic tumor, and you have to perform a splenectomy if it's symptomatic.
Great. Okay. Kevin what, what about a malignancy of the, a malignant tumor of the spleen? What's the most common primary malignant tumor of the spleen and what are some important associations? Yeah. So that's angiosarcoma and this is a commonly tested. It's associated with vinyl chloride and thorium dioxide exposure.
Great. Absolutely. Yeah. Those are just kind of a buzzword associations that, that you need to know. Angiosarcoma primary malignant tumor of the spleen. There can be aggressive, they're high, very high mortality. But you can perform a splenectomy if caught in time, but unfortunately they typically present very advanced and late.
Okay. How about lymphomas, John? Yeah, so the one you might see is not Hodgkin's [00:11:00] lymphoma. And most common is CLL. You need to perform a splenectomy if you have anemia or thrombocytopenia. Yeah. CLL most common lymphoma, the spleen splenectomy for anemia or thrombocytopenia. Kevin back to you for splenic artery aneurysms.
Can you talk to me a little bit about how these present and when to treat 'em and, and how to approach 'em? Yeah. So this is the most common visceral artery aneurysm most commonly in women is generally found incidentally on CT scans for other things. And so actually the guidelines have changed since we made this absent review, it's now greater than three centimeters is when it's indicated for treatment or pregnant women or women of childbearing age, regardless of size.
And so the way we treat these is generally with an endovascular coil embolization of the aneurysm. Or occasionally you can do a placement of a covered stent there's a few scenarios where you can have a very distal aneurysm in the high limb of the spleen. That's kind of not accessible to co limbalization.
So then you'd maybe need to do a splenectomy. Yeah. So, as you mentioned, the thing to watch for [00:12:00] is is those pregnant women or women of childbearing age. It's because there's a 70 percent risk of rupture during pregnancy and that's the way you may see it show up on the exam is somebody who shows up with spontaneous hemoperitoneum and they're unstable, a pregnant patient.
So you want to be concerned that there's a splenic artery aneurysm. John, let's move on and talk about post splenectomy infection. We talked about this a little bit in the trauma chapter, but let's dive a little deeper. bit deeper. What can you tell me about post splenectomy infections? Yeah. So when you remove the spleen, you get decreased levels of IgM and IgG.
That leads to increased susceptibility to encapsulate organoids, such as strep pneumo and the serial meningitis and atrial influenza. Okay. When do you vaccinate patients? So you want to typically vaccinate these patients two weeks prior to an electrosplenectomy. Or prior to hospital discharge following emergent splenectomy.
Yeah. Great. If you can get two weeks out post op [00:13:00] it's recommended, but like you say, for trauma patients without reliable followup you'll want to make sure that they're vaccinated before they leave the hospital. Now, what about overwhelming post splenectomy infection? Who's at risk for this?
Yeah. The highest risk group is in children who've had spleen removed. You know, early in their life and especially specifically those with hemologic disease such as beta thalassemia. Yeah. So those beta thalassemia children are a very high risk for, or I wouldn't say very high, but the highest risk for overwhelming post plenectomy infection.
And I have seen that exact question show up on the exam. So John, if you're concerned or suspicious for Opsy what do you do? Yeah, you want to draw blood cultures, but you don't wait to get a positive culture to start broad spectrum antibiotics. You just start them immediately. Okay, is there any role for prophylactic antibiotics?
You can consider it in children less than 10 years old but definitely not in adults. Yeah. Yeah. Sometimes you'll, people will have a prescription for antibiotics. So if they start to develop [00:14:00] signs or symptoms, they can, you know, start antibiotics very, very soon. Again, consider it for those very high risk children, but for the most part people are not doing prophylactic antibiotics for, for Opsy.
Okay. So that that wraps up our review of spleen was, we're going to move right into some quick hits. So, as always. Let's start with Kevin. So you have a patient that's status post splenectomy for ITP with persistent thrombocytopenia and a peripheral smear with howl jolly bodies. What are you thinking?
Yeah. So in this situation we're thinking about there's possibly an accessory spleen, and what are you gonna do? How do you, how would you confirm or, or rule that out? So you can actually do a radionucleotide scan to look for that. You tag the red blood cells to look for an accessory spleen. Yeah. So a tag, red blood cell scan is what is what you do and the most common location.
The splenic hilum. Perfect. John, most common organism associated associated with that OPSI, that overwhelming post splenectomy infection. Yeah. So of the three encapsulated organisms, strep [00:15:00] pneumo would be the highest. Yep. Strep pneumo most common. Okay. Kevin, you have a patient with abdominal pain and a CT with a spleen in the right lower quadrant.
Abdominal ultrasound shows no flow in the splenic vein. What's the diagnosis? Yeah, this is a wandering spleen. And what's that, what's that caused by? So you don't, you have a failure of the fusion of the dorsal mesogastrum leading to the lack of splenic ligaments. Yeah. So that puts 'em at risk for splenic torsion and infarction.
What's the treatment splenectomy of splenic infarction. Otherwise you can do a sp opexy. Perfect. Okay. John, your most common source of post splenectomy bleeding as a pesky short gastrics. Yeah, it's always a short gastrics. Okay. Kevin treatment of portal vein thrombosis after a splenectomy anticoagulation?
Sure. Anticoagulation. Okay. John, you have a patient with abdominal pain following splenectomy. CT shows a large, low attenuation contained fluid collection in the, in the surgical bed of the lesser sac. What's the diagnosis? Now, you weren't careful [00:16:00] during the operation and you injured the tail of the pancreas, so it's probably a pancreatic leak.
Perfect. Yeah, you gotta watch for that tail of the pancreas during a splenectomy for sure. And what's the treatment for this? You usually can manage these with a percutaneous drain. Yeah, percutaneous drain. Excellent. Kevin, you have a patient with a fever, hemolytic anemia, renal failure, purpura.
Neurologic changes, diagnosis. It sounds like this patient has thrombotic, thrombocytopenia, and purpura. These patients generally have fever, anemia, thrombocytopenia, and then renal neurologic manifestations. Yeah, so this is caused by a defective ADAMS13 metalloproteinase, which is a von Willebrand's cleaving protein.
And this results in platelet aggregation in the microvasculature. And so what's the treatment for it? Plasmaphoresis. Perfect. Alright, so that wraps up our review of the spleen abscite review behind the knife. Thanks for listening. We'll see you next time.