Splenic injuries, whether from penetrating trauma, such as a gunshot or knife wound, or from blunt trauma via motor vehicle crash or fall, are common and can be lethal. We will focus on blunt splenic injury which is often times the first or second most commonly injured solid organ in the abdomen along with the liver. In the past if the spleen was injured the treatment was a splenectomy, the removal of the spleen through an abdominal incision. With greater understanding of the splenic anatomy and function, and natural course of splenic injuries, the management has evolved into a more conservative approach though a splenectomy may still be required in some situations.
The spleen is located in the left upper quadrant of the abdomen protected under the 9-12th ribs with its main blood supply being the splenic artery. The spleen has many functions including filtering or removing old poorly functioning red blood cells, catching bacteria, and producing antibodies. After removal of the spleen, these functions are lost and the patient could be susceptible to an overwhelming post-splenectomy infections from bacteria such as streptococcus pneumoniae, neisseria meningitidis, and hemophilus influenza. To reduce this risk, patients who undergo surgery to remove their spleen receive vaccines against these bacteria.
As with all injured patients, the initial management with blunt splenic trauma is focused on airway, breathing and circulation, commonly known as the primary survey of trauma evaluation. At this point the patient falls into one of two categories: hemodynamically stable or unstable based on their vital signs (blood pressure and heart rate). If the patient has a low blood pressure and/or a high heart rate (unstable), the trauma surgeon must identify the cause, which is often due to bleeding. Next the trauma surgeon determines the location of the bleeding. If it appears that the abdomen is the source, the patient, the patient may need to be taken to the operating room emergently for exploratory abdominal surgery. If a splenic injury with bleeding is found, removal of the spleen (splenectomy) may be required.
If instead the patient’s vital signs are normal (hemodynamically stable), a CT scan of the abdomen/pelvis may be done to evaluate potential trauma to the abdomen. At this point if the patient is found to have a splenic laceration it is graded according to the AAST splenic injury scale (Table 1). Other factors such as intravenous contrast extravasation or “blush” can also be identified via the CT scan, which indicates that there may be active bleeding in progress in which case a hemodynamically stable patient may be sent to interventional radiology so that an angiogram can be performed and a potential active bleeding vessel can be embolized or coiled to stop any further bleeding. The patient then may be observed in the ICU/floor depending on severity and other trauma to the patient. Close monitoring of the patient’s condition, vital signs, blood tests and serial abdominal exams are required in order to assess the stability of the bleeding from the injury. The trauma surgeon must be prepared to operate 24/7 in case recurrent bleeding develops after a period of stability. Thus, these patients are best managed at a trauma center, which has the necessary resources to intervene quickly. If the patient remains stable the patient's diet and activity can slowly be started after 24 hrs or depending on the individual institution's protocols.
Whether the patient undergoes surgery or is managed non-operatively there are risks and complications associated with either strategy. After surgery there is always a small risk of infection and additionally bleeding from the procedure. If the spleen has been removed, the patient is at risk for certain bacterial infections, as discussed earlier and will require vaccinations. There is also a risk during the procedure of injuring the pancreas or other organs necessitating additional procedures. With the non-operative strategy there is a risk of delayed bleeding which may require an operation to remove the spleen. Also if the patient is selected for nonoperative management there is a chance of a missed associated injury in the abdomen such as a bowel injury.
As a result of understanding the function of the spleen, natural evolution of the splenic injury, improving technology and adjuncts such as angiogram the trauma surgeons are better able to manage blunt spleen injuries nonoperatively more successfully than before. Managing a hemodynamically unstable patient suspected of having an intra-abdominal injury often requires an immediate surgery for abdominal exploration. However, out of the patients managed nonoperatively there still is a set of patients that fail this type of management who will require surgical intervention and it is in those patients that the trauma surgeon must be vigilant. Blunt splenic trauma management has evolved significantly over the last few decades and as our understanding of the injury and its evolution improves so does our ability to manage the splenic injury whether it's nonoperatively or surgically.
Authors: Nimitt Patel M.D and Louis Alarcon M.D. (May 2012)