You are in: eMedicine Specialties > Trauma > Abdominal Trauma Abdominal Trauma, PenetratingArticle Last Updated: Jun 12, 2007AUTHOR AND EDITOR INFORMATIONAuthor: Katie Jo Stanton-Maxey, MD, Resident Physician, Department of Surgery, Indiana University School of Medicine Katie Jo Stanton-Maxey is a member of the following medical societies: Alpha Omega Alpha Coauthor(s): H Scott Bjerke, MD, FACS, Clinical Associate Professor, Department of Surgery, Indiana University School of Medicine, Medical Director of Trauma Services, Methodist Hospital, Clarian Health Partners, Inc Editors: Ernest Dunn, MD, Program Director of General Surgery, Director of Trauma and Critical Care, Clinical Associate Professor, Department of Surgery, Methodist Hospitals of Dallas, University of Texas Southwestern; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Robert L Sheridan, MD, Assistant Chief of Staff, Chief of Burn Surgery, Shriners Burns Hospital; Associate Professor of Surgery, Department of Surgery, Division of Trauma and Burns, Massachusetts General Hospital and Harvard Medical School; Paolo Zamboni, MD, Professor of Surgery, Chief of Day Surgery Unit, Chair of Vascular Diseases Center, University of Ferrara, Italy; John Geibel, MD, DSc, MA, Professor, Department of Surgery, Section of Gastrointestinal Medicine and Department of Cellular and Molecular Physiology, Yale University School of Medicine; Director of Surgical Research, Department of Surgery, Yale-New Haven Hospital Author and Editor Disclosure Synonyms and related keywords: gunshot wound, GSW, gut shot, stab wound, missile injury, celiotomy, diagnostic peritoneal lavage, DPL, diagnostic laparoscopy, intra-abdominal injuries, intraabdominal injuries, advanced trauma life support, ATLS INTRODUCTIONHistory of the ProcedureThe management of penetrating abdominal trauma (PAT) has evolved greatly over the last century. Prior to World War I, penetrating trauma was managed expectantly. During World War II, however, studies showed that early laparotomy improved survival. By the late 1950s, laparotomy was the standard treatment of patients with PAT. In 1960, Shaftan suggested the selective management of patients with abdominal stab wounds after observing an increased rate of laparotomies without identifiable injuries. More recently, expectant management has also been used in the treatment of specific gunshot wounds (GSWs) to the abdomen. The introduction and refinement of diagnostic procedures and imaging studies, including peritoneal lavage, laparoscopy, CT scan, and focused ultrasound, have directed the evolution of PAT management. ProblemPenetrating abdominal injury implies that either a GSW or a stab wound has violated the abdominal cavity. FrequencyIn the Age-adjusted firearm death rates are 2-7 times higher for non-Hispanic black males as compared to males of other ethnicities. For non-Hispanic whites, most firearms deaths are due to suicide. PathophysiologyA GSW is caused by a missile propelled by combustion of powder. These wounds involve high-energy transfer and, consequently, can have an unpredictable pattern of injuries. Secondary missiles, such as bullet and bone fragments, can inflict additional damage. Military and hunting firearms have higher missile velocity than handguns, resulting in even higher energy transfer. Close-range shotgun injuries often cause significant tissue damage and should be considered high-energy transfer injuries as well. ClinicalAssessment of the patient begins at the scene of the incident by emergency medical service ( Upon arrival at the emergency department, communication of the incident history and the patient's vital signs to the emergency or trauma team is of paramount importance. Advanced trauma life support protocols are initiated. Airway protection and ventilatory support are followed by circulatory resuscitation with fluid infusion. Patients who present with hypotension are already in class III shock (30-40% blood volume loss), and they should receive blood products as soon as possible. Examination of the abdomen in a patient who is awake may indicate peritoneal signs, such as pain and guarding and rebound tenderness, which necessitate exploration without delay. Abdominal distension in an unresponsive patient may indicate active internal bleeding that also requires exploration, especially in combination with hypotension. Rectal examination is performed on all patients with PAT, as blood per rectum and high-riding prostate can indicate bowel injury and genitourinary tract injury, respectively. Notation of blood at the urethral meatus is also a sign of genitourinary tract injury. When immediate operative intervention is not requisite, further evaluation ensues with laboratory testing and diagnostic and imaging studies. INDICATIONSGSWs are associated with a high incidence of intra-abdominal injuries. Nearly all patients with GSWs require laparotomy. Recent reports of nonoperative management of GSWs to the abdomen are discussed later in this article. Stab wounds are associated with a significantly lower incidence of intra-abdominal injuries; therefore, expectant management is indicated in hemodynamically stable patients. Many protocols have been developed for determination of abdominal wall penetration of stab wounds to the torso (see Media file 1). RELEVANT ANATOMYEach area of the torso has anatomical boundaries, as follows:
Retroperitoneal organs include the duodenum, pancreas, kidneys, ureters, urinary bladder, ascending and descending colon, major abdominal vessels, and rectum. CONTRAINDICATIONSPatients without recordable cardiac activity upon presentation should not be further resuscitated. WORKUPLab StudiesAll patients should undergo certain basic laboratory testing, as follows:
Patients who arrive in shock should be typed and crossed for 4-8 units packed red blood cells. Ethanol and drug screens are also standard practice in trauma patients. Studies have shown that even brief intervention and counseling in patients at the time of admission for trauma injury has positive outcomes. Imaging StudiesMany imaging modalities can be useful in the evaluation of a patient with PAT. Plain radiograph Chest radiograph is obtained on all patients because penetration of the chest cavity cannot be ruled out, even with abdominal stab wounds or even-numbered GSWs. Chest radiograph can reveal hemothoraces/pneumothoraces or irregularities of the cardiac silhouette, which can be a sign of cardiac injury or great vessel injury. Air under the diaphragm indicates peritoneal penetration. Abdominal radiographs in 2 views (ie, AP, lateral) are also obtained on all patients with GSWs to help determine missile trajectory and to account for retained missiles in patients with odd-numbered GSWs. The focused assessment with sonography for trauma (FAST) uses 4 views of the chest and the abdomen (ie, pericardial, right upper quadrant, left upper quadrant, pelvis) to evaluate for pericardial fluid indicative of cardiac injury and for free peritoneal fluid. Free fluid in the abdomen can be a sign of hemorrhage secondary to liver or splenic laceration or, less commonly, of spillage secondary to hollow viscus injury. CT scan is used in the evaluation of patients with stab wounds to the flank and the back and in the evaluation of selected patients with abdominal stab wounds and GSWs. Triple contrast (ie, oral, intravenous, rectal) is often used to maximize the sensitivity of this study for peritoneal penetration and intra-abdominal organ injury. Specific signs of peritoneal penetration include a wound tract outlined by hemorrhage, air, or bullet or bone fragments that clearly extend into the peritoneal cavity; the presence of intraperitoneal free air, free fluid, or bullet fragments; and obvious intraperitoneal organ injury. This study is more often used intraoperatively to assess contralateral renal function in a patient with kidney damage necessitating nephrectomy. Diagnostic ProceduresIn patients with PAT, a limited number of procedures are necessary for diagnosis and/or treatment. All patients undergoing endotracheal intubation require decompression of the stomach to decrease the risk of aspiration. Blood in the nasogastric tube can indicate upper gastrointestinal injury. Catheter insertion is required to monitor the fluid resuscitation status of the patient with PAT. The presence of blood in the urine is a sign of genitourinary tract injury. Diagnostic peritoneal lavage (DPL) can be performed via either a closed method (ie, small skin puncture with blind insertion of catheter over guidewire) or an open method (ie, insertion of catheter under direct vision after exposure of the peritoneum through a small infraumbilical incision). Aspiration of gross blood is positive for peritoneal penetration and organ injury. If aspiration is negative, 1 liter of sodium chloride is administered through the catheter and then retrieved by gravity siphonage. The fluid is then evaluated for the presence of red blood cells (>10,000/mm3), white blood cells (>500/mm3), bile, fibers, or particles, any of which indicate peritoneal penetration and organ injury. While very sensitive and specific, DPL requires a fair amount of time to perform, and it has been supplanted in many institution protocols by FAST, CT scan, and/or laparoscopy. Tube thoracostomy Patients with penetrating wounds to the thoracoabdominal area may require chest tube placement. Absent or significantly decreased unilateral breath sounds necessitate immediate tube thoracostomy to relieve hemothorax/pneumothorax. In other patients, hemothorax/pneumothorax will be identified on chest radiograph. A large-bore (38-40F) chest tube should be placed in the midaxillary line at the fifth intercostal space. Time permitting, liberal local anesthesia is preferred in the patient who is awake. The tube is placed to 20-cm wall suction, and, postprocedure, chest radiograph is performed to confirm placement. Rigid sigmoidoscopy Patients with blood on rectal examination who are otherwise being managed expectantly (mostly stab wounds) should undergo rigid sigmoidoscopy to rule out rectal injury. TREATMENTMedical therapyResuscitation of the patient with PAT begins immediately upon arrival. At least 2 large-bore peripheral intravenous catheters should be secured; central venous access may be necessary. Fluids should be administered rapidly. Normal saline or Ringer’s lactate solution can be used for crystalloid resuscitation. Patients arriving in shock or with obvious significant bleeding should receive blood products as quickly as possible. Arterial access for continuous blood pressure monitoring is standard. Efforts should be made to limit hypothermia, including warm blankets and prewarmed fluids. Antibiotics should be administered to patients undergoing exploration. Preoperative detailsSurgical intervention begins with preparation of the patient in the operating room. The patient is placed in the supine position with arms extended. The entire chest, abdomen, and pelvis, including the upper thighs, are prepped and draped. This allows for access to the chest, should the injury tract extend above the diaphragm, and to the vasculature of the groins, should reconstruction become necessary. Fluids and blood products should be readily available (and administered via warm lines), and warming devices should be placed on the patient’s upper and/or lower extremities. Entering the abdominal cavity can release tamponade, resulting in a precipitous drop in blood pressure, so the anesthesia team must be informed when the midline incision is made. Intraoperative detailsEssential components to the trauma laparotomy include control of bleeding, identification of injuries, control of contamination, and reconstruction (if possible). Initial control of bleeding is accomplished with 4 quadrant packing using laparotomy pads. The abdominal wall is retracted, the falciform ligament is taken down, and packs are placed above the liver and the spleen and in both sides of the pelvis after the bowel is swept cephalad. Once anesthesia has been given time to catch up with fluid resuscitation, the packs are removed one quadrant at a time, starting away from the sites of apparent bleeding. All areas are examined for injuries; each solid organ and the entire bowel are inspected. Contamination is controlled with the use of clamps, staples, or suture closures. Depending on the character of the defect(s), resection may be necessary. If the patient is stable enough to continue the operation, reconstruction may then be performed. Diaphragm Penetrating injuries to the diaphragm are graded as follows: (I) contusion; (II) laceration, <2 cm; (III) laceration, 2-10 cm; (IV) laceration, >10 cm; and (V) total tissue loss, >25 cm2. Lower grade injuries may be repaired either via laparotomy or with laparoscopic or thoracoscopic techniques. Essential components of repair include an airtight closure with nonabsorbable suture and liberal saline lavage of the hemithorax if there has been a concomitant bowel injury with soilage of the field. The closure may be running or interrupted, and a chest tube is often placed for drainage. Large defects may require placement of a prosthetic patch. Liver injuries are also classified by grade. Components of the different grades pertinent to penetrating injuries include the following: (I) nonbleeding capsular tears, <1 cm deep; (II) lacerations, 1-3 cm deep and <10 cm long; (III) laceration, >3 cm deep; (IV) parenchymal disruption involving 25-75% of a lobe or 1-3 segments; (V) parenchymal disruption of >75% of a lobe or >3 segments or juxtahepatic venous injury; and (VI) hepatic avulsion. Operative management of liver injuries can involve many techniques, including simple packing or wrapping, local hemostasis, and resectional debridement. Knowledge of hepatic anatomy is crucial, because exposure and vascular control are necessary for the safe repair of injuries. Packing may successfully control minor hemorrhage; however, packs may need to be left in place and the abdomen closed temporarily. After resuscitation is complete, the patient may return to the operating room for removal of the packs, at which point bleeding is most often resolved. Penetrating injuries to the spleen can cause significant bleeding. Irreparable vascular injuries, including total avulsion and extensive lacerations, are indications for splenectomy. Splenectomy may also be necessary for less substantial injuries for the patient in extremis. Time permitting, the spleen is completely mobilized, and care should be taken not to injure the pancreas. If there is a reparable laceration, digital pressure should be applied at the hilum and interrupted pledgeted splenorrhaphy performed. Kidney Injuries to the kidney are also graded according to severity, as follows: (I) contusion; (II) lacerations, <1 cm; (III) lacerations, >1 cm; (IV) lacerations to the collecting system; and (V) vascular avulsion. As with spleen injuries, the kidney is salvaged with renography, using pledgeted sutures and wrapping, and capsular reapproximation if at all possible. If nephrectomy is deemed necessary because of the severity of injury or instability of the patient, an intraoperative intravenous pylorogram is performed to confirm function of the contralateral kidney. Stomach Exposure and thorough inspection of the stomach is necessary to evaluate and treat penetrating injuries to the stomach. This is facilitated by opening of the gastrocolic ligament, which allows entrance into the lesser sac. Injuries extending into the lumen may be repaired quickly with a stapling device. Duodenum Injuries to the duodenum are graded as follows: (I) hematoma; (II) partial thickness laceration; (III) laceration disrupting <50% circumference of D1, D3, D4, or 50-75% circumference of D2; (IV) laceration disrupting 50-100% circumference of D1, D3, D4, or >75% circumference of D2, or involving the ampulla or distal common bile duct; and (V) massive disruption of the duodenopancreatic complex or devascularization of the duodenum. Pancreatic injuries are graded according to the presence or absence of ductal injuries. Grades I and II include superficial or major laceration or contusion without ductal injury, respectively. Grade III injuries are distal transections without duct injury or tissue loss. Grade IV lacerations involve proximal transection or parenchymal injury involving the ampulla. Grade V injuries are massive disruptions of the pancreatic head. Control of contamination is of high priority with penetrating injuries to the small bowel. Clamps or staples may be used for temporary control as the entire length of the small bowel is examined. If less than 50% of the bowel circumference is disrupted, the defect can be closed in a transverse fashion with sutures or staples. If there is a single defect larger than 50% circumference, there are multiple defects in a short segment of bowel, or there is a devascularizing injury to the mesentery, resection of the involved segment is appropriate. Side-to-side stapled anastomosis can be accomplished quickly. In the unstable patient, a damage-control procedure may be performed, with control of contamination and resection of devitalized segments without anastomosis. The patient returns to the operating room within 24-48 hours for reexploration, resection of any further devitalized segments, and restoration of continuity with one or more anastomoses. Colon The management of colonic injuries depends on the extent of the defect, the amount of contamination, and the stability of the patient. Primary repair may be considered if the patient is hemodynamically stable and if the injury is fairly small with minimal fecal contamination. If the patient has multiple injuries; if the patient has required significant blood product resuscitation; if the patient is acidotic, hypothermic, and coagulopathic; and/or if there is a large defect (>50% of the circumference) and considerable fecal spillage, then a diverting colostomy should be performed. Postoperative detailsPatients should be monitored closely in the surgical intensive care unit after trauma laparotomy. Many patients will remain intubated and require ventilatory support. Attention should be paid to warming the patient, to continuing fluid and blood product resuscitation, to replacing electrolytes, and to monitoring drain outputs. Patients with evidence of ongoing bleeding may benefit from angiographic evaluation for possible embolization; some require reexploration for control of hemorrhage. Patients who have undergone damage-control procedures and/or who have temporary abdominal closures must return to the operating room within 24-48 hours for definitive repair. Follow-upFor excellent patient education resources, visit eMedicine's Wounds Center. Also, see eMedicine's patient education article Puncture Wound. COMPLICATIONSEarly postoperative complications include ongoing bleeding, coagulopathy, and abdominal compartment syndrome. The latter is treated with opening of the abdomen and temporary closure. Later complications include acute respiratory distress syndrome, pneumonia, sepsis, intra-abdominal fluid collections, wound infections, and enterocutaneous fistulae. Late complications include small bowel obstruction and incisional hernias. OUTCOME AND PROGNOSISThe outcome for patients with PAT varies greatly depending on the extent of injury and the interventions required for repair. In a series by Nicholas of 250 patients with PAT and positive laparotomies, the overall survival was 86.8%.1 Mortality was found to be associated with the number of organs injured, vascular injury, and the need for damage-control surgery, emergency department thoracotomy, or operating room thoracotomy. While damage-control surgery has been used with some success in the management of patients with extensive abdominal trauma, it is associated with significant morbidity, including sepsis, intra-abdominal abscess, and gastrointestinal fistula, according to Nicholas.1 FUTURE AND CONTROVERSIESManagement of the patient with PAT 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 patients or, more specifically, the injury patterns suitable for this type of management. Several different methods have been used to establish the injuries present and therefore the need for operative intervention in patients with PAT. 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. Laparoscopy Laparoscopy was first used in cases of PAT in the late 1970s. However, the technique was not widely used until much later after equipment had been improved and surgeon experience had grown. Diagnostic laparoscopy can be used to determine the need for laparotomy in patients with penetrating injury patterns. Multiple studies have shown a reduction in unnecessary laparotomies in patients with a penetrating mechanism but no identifiable organ injury who underwent diagnostic laparoscopy. A retrospective study of 344 patients with abdominal exploration for PAT revealed 44 laparoscopies, half of which were negative for penetration and resulted in avoidance of laparotomy.2 A prospective study of 99 patients with abdominal trauma who underwent laparoscopy showed that diagnostic laparoscopy was negative in 62% of the patients with PAT. The use of diagnostic laparoscopy reduced the rate of unnecessary laparotomy from 78.9% to 16.9% in this group of patients with PAT.3 Triple-contrast helical CT has been evaluated as a diagnostic modality in hemodynamically stable patients with penetrating torso trauma. Oral, intravenous, and rectal contrasts are administered, and the images are reviewed for evidence of peritoneal penetration and visceral injuries. In a prospective study of 200 patients, CT was found to be 97% sensitive and 98% specific for peritoneal violation.4 Laparotomy based on CT findings in 38 of these patients was considered therapeutic in 87%, nontherapeutic in 8%, and negative in 5%. These results were comparable to others obtained with the use of clinical examination, DPL plus local wound exploration, and DPL alone.5, 6, 7 Patient selection is extremely important when considering CT as a diagnostic adjunct in patients with PAT. Ultrasound Ultrasonography has been widely used in the assessment of patients with blunt trauma, but it has only recently been used in the assessment of patients with penetrating injuries. While FAST has been found to be 94-98% specific for abdominal injury in PAT, its sensitivity of 46-67% is not good.8, 9 The rapidity with which FAST can be performed in the trauma setting is useful; however, the need for further testing to rule out occult injury in the event of a negative FAST limits its overall use. FURTHER READINGLawson R, Goosen J. Abdominal Stab Wound Exploration. eMedicine from WebMD. Updated May 31, 2007. Available at: http://www.emedicine.com/proc/topic82869.htm. MULTIMEDIA
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Abdominal Trauma, Penetrating excerpt Article Last Updated: Jun 12, 2007 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||