Abdominal and Pelvic Injury

The evaluation and management of abdominal trauma must be done in the context of the mechanism of injury. Abdominal injuries resulting from blunt forces must be specifically sought out with diagnostic testing, whereas those resulting from gunshot wounds, for example, may not require any diagnostic tests prior to operative intervention.

The evaluation of blunt abdominal trauma due to motor vehicle crashes, direct blows, or falls has evolved in the past decade. Diagnostic peritoneal lavage (DPL) used to be the standard, rapid method to detect intraperitoneal blood. This has been largely replaced by the FAST examination in most trauma centers. The FAST examination is a quick, noninvasive bedside examination that uses ultrasound to detect peritoneal or pericardial fluid. It has a reported sensitivity rate of up to 88 percent, a specificity rate of about 99 percent, and accuracy rate of 98 percent, but cannot provide detailed information about specific organ injury.38 It is less useful to evaluate retroperitoneal injuries and hollow viscus injuries. At our institution we have found it to be most useful in hypotensive patients who are unstable to go to CT scan, but need a rapid test to assess for intra-abdominal hemorrhage that would require surgery.

CT scanning is the primary diagnostic modality in hemodynamically stable patients who have sustained blunt abdominal trauma. The current generation helical scanners provide rapid, high quality images that are very specific for organ injury and have an accuracy of around 95 percent. A CT scan can miss bowel injuries; therefore, there is still no substitute for comprehensive initial and serial physical examinations of the patient who has sustained blunt trauma. The CT scan is also useful for detecting injury to retroperi-toneal organs, such as the kidney, pancreas, and duodenum.

The spleen is the most commonly injured abdominal organ following blunt trauma. Injury to the spleen is frequently associated with left lower chest trauma and lower rib fractures. Hemodynamically unstable patients with a positive FAST examination should go straight to the operating room for exploratory laparotomy and either splenectomy or splenorrhaphy. Stable patients undergo CT scanning, which enables one to grade the severity of the spleen injury, which, in turn, is predictive of the success of nonoperative management. A trend toward nonoperative management of spleen injuries in recent years is based on the known immunologic function of the intact spleen and the increased susceptibility to the overwhelming postsplenec-tomy infection (OPSI) syndrome in asplenic patients. The incidence of OPSI is estimated to be about 1-2 percent following splenectomy in adults, but the mortality may be as high as 50 percent. Infections from encapsulated organisms, such as Pneumococcus and Meningococcus, predominate in splenec-tomized patients, but there is also evidence for increased risk from viral illness and nonencapsulated bacteria. The nonoperative management of spleen

Abdominal Strain Pelvic Crest

Figure 2-8 (A) Pre- and (B) postangiographic embolization of a high-grade splenic laceration involving mainly the lower pole of the spleen. Embolization reduces the blood flow to the spleen, thereby reducing hemorrhage and increasing the success of nonoperative management of this injury.

injuries is successful over 80 percent of the time; this success rate may be further enhanced by more recent angioembolization techniques by interventional radiologists (Fig. 2-8). It is important to conduct serial examinations and hematocrit determinations in patients who have sustained blunt splenic injury and are managed nonoperatively because some of these patients, particularly with higher-grade injuries, will develop delayed bleeding complications requiring surgery.39,40

Liver injuries are also common following abdominal trauma. As with spleen injuries, liver injuries due to blunt trauma are frequently managed nonoperatively, as long as concomitant bowel injuries are ruled out. CT scanning, again, is the diagnostic test of choice in stable patients because it allows one to grade the severity of the injury to the liver. Unstable patients with large liver lacerations may sustain large blood loss and transfusion requirements resulting in the lethal triad of hypothermia, acidosis, and coagulopa-thy. In these situations, a damage control laparotomy is frequently done in order to stop any surgical bleeding, stop any ongoing contamination from bowel injuries, and tamponade nonsurgical bleeding with laparotomy packs. The patient is then taken to the ICU for further resuscitation and correction of hypothermia, coagulopathy, and acidosis. The open abdomen also reduces the risk of abdominal compartment syndrome secondary to massive fluid resuscitation.41 A definitive laparotomy procedure is then performed in 1 or 2 days. This approach to patients with massive liver injuries, or other intra-abdominal injuries resulting in massive fluid resuscitation and blood product transfusion, has yielded reduced mortality rates and improved outcomes in patients sustaining severe abdominal injuries.42

Gunshot wounds to the abdomen that traverse the peritoneum are generally best treated by expeditious exploratory laparotomy. Because of the large surface area of the bowel, intestinal injuries are commonly encountered following penetrating abdominal trauma. The overriding principle of the operative management of abdominal gunshot wounds is to thoroughly explore the entire abdomen, tracing the missile tract from entry to exit, examining the entire length of intestine, and inspecting the abdominal viscera and vasculature in proximity to the missile path.

Pelvic fractures are common injuries that are among the most challenging that a trauma surgeon will encounter. Although many pelvic fractures are relatively minor and may not even require specific treatment, disruption of the pelvic ring takes considerable force that may result in life-threatening hemorrhage and associated injuries. In fact, the main cause of death in patients with pelvic fractures is exsanguinating hemorrhage. Pelvic fractures may result from (1) AP compression, producing an open book type disruption of the pelvis; (2) lateral compression; and (3) vertical shear, resulting in Malgaigne fractures typically seen after a fall from heights and other mechanisms that produce a vertically oriented force applied to the anterior and posterior aspects of the pelvic ring (Fig. 2-9).

Figure 2-9 Mechanisms of pelvic disruption. (A) An AP force resulting in an open book pelvis. (B) A lateral compressive force disrupting the pelvic ring. (C) A vertical shear force, or Malgaigne, fracture. (Source:Adapted from Wilson RF Tyburski J, Georgiadis GM. Pelvic fractures. In Wilson RF, Walt AJ, eds., Management of Trauma: Pitfalls and Practice, 2nd ed. Baltimore, MD: Williams & Wilkins, 1996: 580-581.)

Figure 2-9 Mechanisms of pelvic disruption. (A) An AP force resulting in an open book pelvis. (B) A lateral compressive force disrupting the pelvic ring. (C) A vertical shear force, or Malgaigne, fracture. (Source:Adapted from Wilson RF Tyburski J, Georgiadis GM. Pelvic fractures. In Wilson RF, Walt AJ, eds., Management of Trauma: Pitfalls and Practice, 2nd ed. Baltimore, MD: Williams & Wilkins, 1996: 580-581.)

Tyburski Trauma
Figure 2-9 (Continued)

Goals of immediate evaluation and management of patients with pelvic fractures are to stabilize the bony pelvis, assess for intra-abdominal hemorrhage or other associated injuries that may require emergent surgery, control hemorrhage, and provide adequate resuscitation. An unstable pelvis, for instance one with a large open book component, should be stabilized initially with a pelvic binder or even a crossed bedsheet in order to reduce the increased pelvic volume and pelvic hemorrhage. Further stabilization with an external fixator device may also be expeditiously applied in the emergency department or operating room. Hypotensive patients with pelvic fractures undergo a FAST examination, specifically looking for fluid in the upper abdomen around the spleen and liver; such findings imply concomitant visceral injury requiring immediate surgery. If hemorrhage from extrapelvic sources has been ruled out and the patient remains hypotensive, an immediate arteriogram with angiographic embolization may be lifesaving. Pelvic bleeding is best approached by this method, rather than surgery, unless perineal, rectal, or vaginal lacerations are also present. Once stabilized, CT scan is done to rule out concomitant injuries, including bowel injuries or injuries to the urologic tract. Algorithm for the initial assessment and management of pelvic fractures is indicated in Fig. 2-10.

Management of pelvic fractures

Management of pelvic fractures

Figure 2-10 Algorithm for management of pelvic fractures.
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