Retroperitoneal hematoma: Clinical sciences

A retroperitoneal hematoma is a collection of blood within the retroperitoneal space. It can be caused by injury to parenchymal tissue or vascular structures secondary to blunt trauma, like motor vehicle accidents, or penetrating trauma, like stab or gunshot wounds. Retroperitoneal hematomas may also be a result of non-traumatic causes in patients who recently had percutaneous or endovascular interventions or patients on anticoagulation therapy.

When assessing a patient with signs and symptoms suggestive of a retroperitoneal hematoma, you should first perform an ABCDE assessment to determine if the patient is stable or unstable. Now, if the patient is unstable, first stabilize their airway, breathing, and circulation. This means that you may need to intubate the patient, establish IV access, and administer IV fluids before continuing with your assessment. In addition, perform blood typing and crossmatching, and prepare for massive blood transfusion.

Next, you should obtain a focused history and physical examination. If your patient is conscious, they might report abdominal, flank, or back pain, as well as dizziness or syncope. Additionally, they might have a history of blunt or penetrating trauma, or a recent endovascular procedure. On physical exam, you might find tachycardia or hypotension, and possibly pallor, visible traumatic injuries, or an unstable pelvis.

Additional signs that may lead you to suspect a retroperitoneal hematoma include Grey-Turner, Fox, or Bryant signs. A Grey-Turner sign refers to flank ecchymosis. Fox sign refers to inguinal ecchymosis, and finally, the Bryant sign refers to scrotal ecchymosis. Although these signs may be suggestive of a retroperitoneal bleed, they are not always evident, especially since it often takes days for them to appear.

Alright, if based on history and physical exam you suspect retroperitoneal hematoma, order a CT of the abdomen and pelvis with IV contrast. Imaging might sometimes show additional traumatic injuries, like a pelvic fracture or kidney injury, but the key finding is a complex fluid collection in the retroperitoneal space.

Here is a high-yield fact! The retroperitoneal space is located directly behind the abdominal cavity and is divided into three different zones. The central-medial zone, or Zone 1, extends from the diaphragm to the bifurcation of the aorta. It contains the pancreas, portions of the duodenum, the abdominal aorta, and the inferior vena cava. The perinephric zone, or Zone 2, is located on either side of Zone 1 and contains the kidneys, ureters, and adrenal glands, as well as the ascending and descending colon. Lastly, the pelvic zone, or Zone 3, is located below the aortic bifurcation and contains the distal ureter, distal sigmoid colon, and the rectum, as well as the internal and external iliac arteries and veins.

So, for example, in blunt trauma, retroperitoneal hematoma in Zone 1 might involve major vascular structures, so they usually require an exploratory laparotomy. On the other hand, Zone 3 hematomas likely involve major pelvic injuries and may require pelvic packing to stabilize any bleeding until angioembolization can be performed.

Now, once you have diagnosed a retroperitoneal hematoma, the next step is treatment. Your patient will either require an emergent laparotomy if the retroperitoneal hematoma is in zone 1 or angioembolization if the retroperitoneal hematoma is traumatic. If you suspect, or the CT confirms, additional traumatic injuries, an exploratory laparotomy is preferred since it allows you to address multiple injuries at the same time. Lastly, non-traumatic retroperitoneal hematomas require angioembolization.

Alright, now that unstable patients are taken care of, let’s go all the way back to the ABCDE assessment, and talk about stable patients. When it comes to stable patients, you want to determine if their retroperitoneal hematoma is traumatic or nontraumatic. Your first step is to obtain a focused history and physical examination; and order labs like a CBC, followed by serial hemoglobin and hematocrit levels every 4 to 6 hours, as well as coagulation studies, including PT, INR, and PTT. You should also order a blood type and screen in case your patient needs any blood transfusions during their admission. Now, history might reveal abdominal, flank, or back pain, and blunt or penetrating trauma.