 Welcome to emergency medicine video. This is part 3 of GI Bleed. In this segment, we will discuss the investigation needed for patients with upper and lower GI bleeds. If you have not already done so, we suggest you review part 1 and 2 of GI Bleed above the causes and presentations of upper and lower GI bleeds. We'll first discuss blood work. For any bleeding, it is important to first establish that this is not from a generalized bleeding disorder, such as thermosutopenia or if the patient is taking anticoagulant. Therefore, you will want to do a platelets count. Hemoglobin is also helpful in quantifying the amount of bleeding. In patients with inflammatory processes such as colitis, the white blood cell will be high. Therefore, a CBC should be ordered. In patients who are on anticoagulants or if they have cirrhosis, their coagulation profile will be increased, so an INR and PTT should be ordered. A good trick of seeing if there is blood sitting in the GI tract is that if there is blood sitting in it, the degraded blood will be reabsorbed into the body and that will make the BUN go up. Also, if the patient has become dehydrated from bleeding, the creatinine will go up as well. In patients with GI bleeding from ischemicolitis, their lactate will go up, that's from the gut ischemia, and the patient will be in metabolic acidosis. Therefore, to summarize in patients who are having active GI bleed, a CBC, coagulation profile and bioncretin are fairly standard. In patients that were worried about a psychopathology such as ischemicolitis, a lactate and a VBG would be helpful. In patients with GI bleed, we often do a type in screen in case we have to give them blood later. In patients with breast GI bleed, if we want to give them blood now, you'll want to cross match them for a few units of packed red blood cells. We'll discuss that further in the treatment videos. We'll move on to imaging in the patients with GI bleeds. We don't often think about this, but the loss of a large amount of blood can cause the heart to work much harder and causing a huge demand on the heart. In patients with severe GI bleed, and if they have symptoms that suggestive of coronary artery disease, such as chest pain, and showness of breath, you want to order an ECG to look for ischemia. Now let's move on to more conventional type of imaging. First, X-rays. X-rays are often normal in patients with GI bleed. They're useful in a few things. The first one is perforation, second being about obstruction, that you can see sometimes in patients with inflammatory colitis, particularly if they have surgery in the past. X-ray is also helpful if you think there is a foreign body causing the GI bleeding. If you look at this upright chest X-ray, you notice that there's air under the diaphragm, suggesting there is a viscous perforation. As we discussed before, however, in most cases of GI bleed, the X-ray are going to be normal. Therefore, we move on to CT. CT is quite helpful in diagnosing a few different conditions that can lead to upper and lower GI bleeds. For upper GI bleeds, you can diagnose esophageal varices, perforated ulcers, and sometimes deudonitis and gastritis. You can certainly diagnose aorta enteric fistula. What about for lower GI bleeds? CT can diagnose colitis, tumor, diverticuli. Again, as we talked about before, CT is unable to tell you whether anything is actively bleeding or not. Remember that for the patient to be able to push through the CT scanner, they need to be hemodynamically stable. We now move on to other special tests we do for patients with suspected GI bleeds. Part of what we do is a rectal examination on physical. There are a few pieces of information we might be able to get. First, a fecal called blood test. Blood that's not visible to the naked eye will be picked up by this test. As you can see here, this is the positive control. The color will be this color. Here, when the stool sample is tested, you can see that it has the same color developed under the reagent as the positive control, which means that there might be a cold blood in the samples. The fecal blood blood has a few things that will make it falsely positive. It is best used in patients with undiagnosed low hemoglobin or undiagnosed bleeding source other than the patient with Frank GI bleeds. There are also other things you can see on the rectal exam. On examining the patient, you might be able to see a small anal fissure and that might be the cause of the GI bleeding and the pain. Similarly, you might be able to see hemorrhoids on the rectal exam as well. On the picture here, these are external hemorrhoids. On examination in the rectum, you may be able to feel internal hemorrhoids as well. Sometimes an anal scope is used to look for both anal fissure and hemorrhoids if they're not readily seen on inspection. The main tests we do on patients with GI bleed will be endoscopy. These are done by trained gastroenterologists. In upper GI endoscopy, we will be able to see what's bleeding in the stomach, the esophagus, and the first part of the judenum. On endoscopy, this is what a peptic ulcer might look like. You can appreciate how if it's bleeding actively, you might be very hard to see the base. On endoscopy, these are what esophageal varices would look like. These bulging blood vessels right at the GE junction. Colonoscopy is used to diagnose lower GI bleeds. For colonoscopy, to start, you need a bowel prep. That takes lots of time and is usually not suitable for patients in the emergency department. Also, in massive lower GI bleed, it is also very difficult to visualize the bowel. In a patient with a clean bowel prep, you might be able to see signs of inflammatory colitis, such as this on the colonoscopy. There's also a newer technology known as capsule endoscopy, where the patient swallows a small capsule camera as it goes through the GI tract. It takes pictures. Those pictures are then being analyzed by the gastroenterologist to see if there's any bleeding source. While there is good usage of it in the outpatient setting, it's not very useful if the patient's having a significant bleed in the emergency department, since it would be very difficult to visualize the photos. There are also other tests in GI bleed that tags the red blood cells with a nucleotide injected back to the body and putting the patient through a nuclear imaging to see where they're bleeding from. These tests are now rarely used and we will not be discussing them further here. In this segment, we talk about the investigations in patients for potential GI bleed. We talked about the order set that you will want to do for blood work. We discuss the imaging, such as X-ray, CT, to diagnose the patient with GI bleeds. We also discuss the use of special tests, including a rectal exam, endoscopy, and colonoscopy to diagnose the patient with GI bleeds. In the next video, we'll discuss the treatment of patients with GI bleeds. Thank you for watching.