Penetrating Abdominal Trauma Treatment & Management

The scope of care that paramedics deliver at the scene of the injury has evolved in parallel with the changing standard of care in the hospital setting. Because most deaths occurred from exsanguination associated with prehospital hypotension, trauma system response has been designed to minimize care in the field and expedite transport to the emergency department (ED) and to reduce the time to definitive care.

Prehospital personnel must be well trained in properly assessing patients and in transporting them to the closest appropriate facility or trauma center. The receiving hospital should be notified as soon as possible by radio or ground line to give the ED time to prepare and to alert the appropriate staff.

The mode of transportation also must be considered. In an urban setting with multiple appropriate facilities, the best transport is probably by ground. In the rural setting, where the closest facility is typically 25 minutes or more away, trauma patients' best chance for survival may be transport by air ambulance.

Aggressive intravenous fluid administration to maintain or reach normotension is discouraged in patients with penetrating injury unless the patient manifests severe shock or prolonged transport is expected. Military data suggest that prehospital fluid administration can be guided by the patient’s mentation and the character of the radial pulse. Similarly, the recent military experience in the Middle East has led to a resurgence of interest in the use of tourniquets to control extremity hemorrhage in the prehospital setting.

For discussion of surgical therapy, see Surgical Therapy for Penetrating Abdominal Trauma.

In general, consultation with a general or trauma surgeon should be undertaken for victims of penetrating trauma.

At some centers, trauma surgeons perform the majority of operative repair, while at others, consultants may be involved as individual injuries are identified. For example, a vascular surgeon may repair major arterial and venous injuries or a urologist may address injuries to the bladder, kidneys, and ureters. Trauma surgeons, even if not directly performing care, should oversee the patient's care and postoperative course.

ATLS guidelines exist to help direct the transfer of trauma patients to a designated trauma facility; however, the mode of transportation is not specified. Patients who are potentially unstable and who would require a long ground transport time (ie, >30 min) or a potentially problematic ground transport route (eg, across an inner city) may be better served by air ambulance transport. Airway control is always an important issue and must be addressed appropriately prior to transport.

In general, reasons to transfer patients to a regional resource trauma facility include (1) no operating room or surgeon is available; (2) the patient has multiple or multicavitary injuries; (3) the patient has requirements that cannot be met at the initial receiving facility (eg, neurosurgery, cardiopulmonary bypass, post–solid-organ transplant), or injuries that would overwhelm the initial facility (eg, massive transfusion requirement).

Patients who are unstable or have evidence of injury requiring immediate laparotomy, such as penetrating trauma with vascular injury, should not be transferred until they have had stabilizing surgical intervention. Obviously, if no surgeon is available, transfer may be the only course of action.

Practitioners must be cognizant of Emergency Medical Treatment and Active Labor Act (EMTALA)/Consolidated Omnibus Budget Reconciliation Act (COBRA) violations and document accordingly (see COBRA Laws and EMTALA). This legislation was enacted with the intention of removing economic considerations from important medical decisions in the ED.

The management of abdominal trauma varies according to the following factors:

• Mechanism and location of injury
• Hemodynamic and neurologic status of the patient
• Associated injuries
• Institutional resources

Management of the patient with penetrating abdominal trauma continues to evolve. After many years of obligatory exploration, expectant management of selected patients has become commonplace.

Much of the present controversy involves the determination of which patients or, more specifically, which injury patterns are suitable for expectant management. Several different methods have been used to establish the injuries present and therefore the need for operative intervention in patients with penetrating abdominal trauma. Most trauma centers use an algorithm with multiple diagnostic modalities whose uses are based on the pattern of injuries and the clinical status of the patient.

A team leader should direct resuscitation and coordinate all care. Depending on the institution, it may be an emergency physician, trauma surgeon, or one of their supervised residents. Given the potential for significant injury, a junior level physician should not lead care without direct oversight.

When the patient arrives in the ED, advanced trauma life support (ATLS) protocols are initiated.^[32] The ABCDEs (airway, breathing, circulation, disability, exposure/environment) are assessed. The patient should be placed on a cardiac monitor, pulse oximeter, and 100% nonrebreather oxygen mask. Airway protection and ventilatory support are followed by circulatory resuscitation with fluid infusion.

Antibiotics should be administered to patients undergoing exploration.

Airway

Patients with severe shock or loss of ability to control their airway should be intubated to ensure appropriate oxygenation or ventilation. In general, occult cervical spine injury in penetrating trauma is highly unlikely. Unless there are clear deficits or associated blunt injury, cervical collars are rarely necessary and may hinder resuscitation.

Breathing

Tube thoracostomy or needle decompression should be undertaken immediately for patients with obvious pneumothorax. A patient who is otherwise stable, should have a chest radiograph performed in the trauma room. An upright positioned radiograph during expiration may provide the best evidence of pneumothorax. Ultrasonography for pneumothorax (as part of the Extended Focused Assessment With Sonography for Trauma [eFAST] or Focused Assessment With Sonography for Trauma [FAST] examination) has been shown to be highly accurate and may be used as the initial test, but it should be followed by a radiograph at some point.

Circulation

Resuscitation of the patient with penetrating abdominal trauma begins immediately upon arrival. Fluids should be administered rapidly. Normal saline or lactated Ringer solution can be used for crystalloid resuscitation.

Patients who present with hypotension are already in class III shock (30-40% blood volume loss) and should receive blood products as soon as possible; the same is true of patients with obvious significant bleeding. Consideration should be given to the early activation of massive transfusion protocols and damage control resuscitation in appropriate patients. Specific triggers for each remain to be better elucidated. Arterial access for continuous blood pressure monitoring is standard. Efforts should be made to limit hypothermia, including warm blankets and prewarmed fluids.

The route of intravenous access is important. Large-bore peripheral intravenous catheters (at least 2) in the upper extremities are the resuscitation lines of choice. These allow for rapid volume/blood infusion versus a central line where the infusion rate is slower.

Extensive debate exists in the literature on the amount and end points for resuscitation prior to definitive control of hemorrhage. Animal data and several studies in humans have suggested that "permissive hypotension"—actively or passively allowing the blood pressure to remain in the hypotensive range (ie, systolic pressure less than 90 mm Hg)—may prevent disruption of clot and dilution of clotting factors while maintaining adequate blood viscosity.

While no definite consensus exists, prevailing thought seems to promote limited resuscitation with avoidance of attempting to raise blood pressure to normal or near-normal levels until hemorrhage is definitively controlled.

Disability and exposure

A rapid and brief evaluation for neurologic deficits should be conducted.

All patients with penetrating trauma should be fully undressed. Complete exposure and head-to-toe visualization of the patient is mandatory in a patient with penetrating abdominal trauma. This includes the buttocks, posterior part of the legs, scalp, posterior part of the neck, and perineum. There is little to be gained by practicing spinal immobilization unless spinal injury is obvious.

Further intervention

Depending on the initial assessment, and in all seriously injured patients, a Foley catheter should be placed if possible to monitor urine output and to check for hematuria. In addition, a nasogastric tube (NGT) or orogastric tube (OGT) should be inserted to evaluate for intragastric blood and to decompress the stomach so as to reduce aspiration risk. Appropriate laboratory specimens should be immediately sent to the laboratory for evaluation.

After the initial evaluation, further evaluation depends on the hemodynamics and mechanism of wounds.

Expectant management

Although surgical management has generally been the standard of care for penetrating abdominal injuries, a study in 90 children by Cigdem et al concluded that in the absence of hemodynamic instability or signs of hollow viscus perforation, the majority of abdominal stab wounds and many gunshot wounds in children can initially be managed nonoperatively.^[33]

In this study, patients with hemodynamic instability or signs of bowel perforation underwent immediate laparotomy; the remainder were followed with serial clinical examinations, radiologic evaluation, and hemoglobin levels. Of the 39 children who were managed surgically, 6 (15%) had no significant organ injury found during surgery; of the 51 patients who initially received conservative therapy, 2 children (3.9%) required surgery.^[33]

Patients with blood on rectal examination who are otherwise being managed expectantly (mostly stab wounds) should undergo rigid sigmoidoscopy to rule out rectal injury.

Stab wounds

Unstable patients or those with clear-cut peritonitis should undergo exploratory laparotomy.

Stable patients may have local wound exploration to ascertain whether the peritoneum was violated. If this cannot be performed or if flank or thoracoabdominal wounds are present, other methods must be used.

Diagnostic peritoneal lavage (DPL) remains an option, but it is currently being used less frequently. A positive focused assessment with sonography for trauma (FAST) examination result has a high positive predictive value for a therapeutic laparotomy, but a negative FAST examination result cannot be relied upon to rule out injury.

In patients with thoracoabdominal injury, a chest radiograph should be obtained. If no signs of diaphragmatic injury are present, laparoscopy is usually advocated; although some surgeons will elect not to perform this on patient with a right-sided wound, given the low likelihood of delayed complications.

The use of CT scan is still controversial; some centers use it as a screening test in patients with anterior stab wounds, while others feel the cost-benefit ratio is not justified. A triple contrast CT should be performed on patients with penetrating flank wounds.

Essentially all nonoperative patients, except those who have a wound that clearly does not penetrate the abdomen, should be observed for serial examinations. The literature is beginning to support a shortened time frame of 12 hours, but most centers use about 24 hours.

Gunshot wounds

All unstable patients with gunshot wounds should proceed emergently to the operating room (OR). Abdominal and other radiographs (depending on the possible bullet course and number of wounds) should be taken at some point during the patient's care to account for all bullets.

In the past, all patients with gunshot wounds that were clearly nontangential were taken to the OR for exploration. An increasing body of literature supports CT imaging, with either triple contrast or intravenous contrast alone, to evaluate for intra-abdominal or retroperitoneal injury. This has been shown to significantly decrease the need for laparotomy without a concurrent increase in morbidity.

All hollow viscus injuries need emergent laparotomy. However, isolated liver or spleen injuries are sometimes observed or undergo angioembolization.

Patient disposition relates to the type of facility and to the mechanism of and potential for injury. The most common post-ED disposition for patients with penetrating abdominal trauma is to the OR. Any patient with an obvious reason for laparotomy (eg, evisceration, rigid abdomen, hypotension) should be taken directly to the OR following initial evaluation and resuscitation in the ED.

Some facilities do not have a surgical or OR team available 24 hours a day. In this case, these patients must be transferred to an appropriate facility. Similar concerns occur if the patient's injuries overwhelm the available resources at the receiving facility.

Victims of penetrating abdominal trauma who lose vital signs or who present with exsanguinating hemorrhage that is not controllable with direct external pressure are candidates for an ED left anterolateral-left thoracotomy. The purpose of this procedure is to relieve cardiac tamponade, control cardiac bleeding, obtain proximal aortic control, and provide open cardiac massage to improve cardiopulmonary cerebral resuscitation efforts.

This procedure is performed only in extremely selected circumstances, since survival from abdominal injury requiring a resuscitative ED thoracotomy is rare. It is much more effective if the arrest is due to cardiac injury with thoracoabdominal trauma. Patients who may be considered for thoracotomy are those who had vital signs on arrival or en route, with or without pulseless electrical activity (PEA) on the cardiac monitor. Thoracotomy is rarely successful in blunt trauma.

The surgical procedure is as follows:

• After rapidly preparing and draping the entire chest, make a curvilinear incision from the left sternal border of the fifth intercostal space to the table, paralleling the course of the underlying rib.
• Divide all tissues above the rib with the scalpel.
• Halt respirations.
• Using a finger or Kelly clamp, pierce the intercostal muscle bundle above the rib, then divide with a curved Mayo scissor for the length of the incision.
• Reinflate the lungs.
• Insert a rib spreader with a ratchet mechanism placed laterally.
• Open the pericardium longitudinally to avoid injury to the pericardiacophrenic vessels and the phrenic nerve.
• Subluxing the heart into the left chest allows for open massage.
• Retract the left lung superiorly using a moist laparotomy pad, and divide the inferior pulmonary ligament using Metzenbaum scissors.^[34]
• The tissues overlying and just lateral to the vertebral bodies contain the aorta, esophagus, thoracic duct, and countless nerves. Usually, blunt dissection frees the aorta enough to place a Satinsky or long, curved DeBakey clamp. In certain circumstances, the aorta is not identified easily, and the aorta and esophagus must be clamped en masse in a patient who is in extremis.
• Warm saline is essential to prevent cooling of the heart, and pressor support usually is needed as well.^[34]
• The image below shows a patient after a thoracotomy.An ED thoracotomy has been performed, and the aorta is cross-clamped. Note the proper positioning of the ratchet mechanism of the rib spreader to allow extension of the incision to the right chest for a clamshell thoracotomy if needed. This patient arrived with a weak pulse and a systolic blood pressure of 40 mm Hg and promptly died on the ED stretcher. An ED thoracotomy was performed for cardiopulmonary-cerebral resuscitation.