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Nonoperative management of abdominal gunshot wounds
TRAUMA/REVIEW ARTICLE
Nonoperative Management of Abdominal Gunshot Wounds
John P. Pryor, MD Patrick M. Reilly, MD G. Paul Dabrowski, MD Michael D. Grossman, MD C. William Schwab, MD From the Division of Traumatology and Surgical Critical Care, Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA (Pryor, Reilly, Dabrowski, Schwab); and the Division of Trauma and Critical Care, St. Lukes Regional Medical Center, Bethlehem, PA (Grossman).
Mandatory surgical exploration for gunshot wounds to the abdomen has been a surgical dictum for the greater part of this past century. Although nonoperative management of blunt solid organ injuries and low-energy penetrating injuries such as stab wounds is well established, the same is not true for gunshot wounds. The vast majority of patients who sustain a gunshot injury to the abdomen require immediate laparotomy to control bleeding and contain contamination. Nonoperative treatment of patients with a gunshot injury is gaining acceptance in only a highly selected subset of hemodynamically stable adult patients without peritonitis. Although the physical examination remains the cornerstone in the evaluation of patients with gunshot injury, other techniques such as computed tomography, diagnostic peritoneal lavage, and laparoscopy allow accurate determination of intra-abdominal injury. The ability to exclude internal organ injury nonoperatively avoids the potential complications of unnecessary laparotomy. Clinical data to support selective nonoperative management of certain gunshot injuries to the abdomen are accumulating, but the approach has risks and requires careful collaborative management by emergency physicians and surgeons experienced in the care of penetrating injury. [Ann Emerg Med. 2004;43:344-353.]
INTRODUCTION
0196-0644/$30.00 Copyright © 2004 by the American College of Emergency Physicians. doi:10.1016/mem.2004.422
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The vast majority of patients who sustain a gunshot injury to the abdomen require immediate laparotomy to control bleeding and contain contamination. These patients often present with hemodynamic instability or a physical examination consistent with peritonitis. Nonoperative treatment of patients with a gunshot injury is gaining acceptance in only a highly selected subset of patients without these findings. If the appropriate patients can be identified, however, many unnecessary laparotomies, along with the associated complications, can be avoided. In many ways, nonoperative care for patients with gunshot injury mirrors the recent trends in nonoperative management of other types of traumatic injury. Although nonoperative management of blunt solid organ injuries and low-energy penetrating injuries such as stab wounds is well established, the same is not true for gunshot wounds. Unlike stab injuries, gunshot injuries produce deeper wounding and more tissue destruction and often have unclear trajectories that confuse the anatomic diagnosis. Although the evidence for selective nonoperative management of
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gunshot injuries to the abdomen, back, flank, and pelvis is accumulating, the approach requires mature judgment, experience, and a multimodal approach by emergency physicians and surgeons working together to determine which patients can be treated safely.1 Nonoperative management is attractive because it avoids the morbidity and potential mortality of an unnecessary laparotomy. Unnecessary operations include those in which the surgeon fails to find any injury in the peritoneal, pelvic, or retroperitoneal cavities (ie, negative laparotomy) or finds only minor injuries that do not need surgical repair, such as a nonbleeding liver laceration (ie, nontherapeutic laparotomy). The morbidity of an unnecessary laparotomy has been reported to be as high as 41.3% when problems such as atelectasis, prolonged ileus, and urinary tract infections are included2 to as low as 2.5% when only major complications such as subsequent small bowel obstruction are considered.3 In addition, an unnecessary laparotomy increases the hospital length of stay4 and significantly increases the cost of care.5 Conversely, delayed exploration and treatment of an intra-abdominal injury can cause complications. Surgeons have long advocated mandatory exploration specifically to avoid the morbidity or mortality related to any delay in treatment of a missed intra-abdominal injury. Several recent studies suggest that, in fact, there is no significant increase in complications resulting from a delayed operative procedure in patients who initially lacked positive clinical signs,6,7 which assumes that a change in the physical examination is identified within a reasonable period (<24 hours). Thus, if no immediate indication for operation exists, patients can be safely observed for the development of physical findings that may warrant surgical exploration. HISTORICAL PERSPECTIVE Experience From War
Penetrating trauma has been treated nonoperatively for the greater part of human existence, primarily because surgery was not technologically possible with any real success.8 This method significantly changed during the modern era of surgery, which began after the introduction of anesthesia in 1846. With advances in anesthesia, antisepsis, instrumentation, and surgical technique, surgeons at the beginning of World War I had the ability to perform trauma laparotomies with relative safety. At the same time, soldiers learned to evacu-
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ate the combat injured quickly to field hospitals where surgery could be performed. Although this procedure led to a lower overall number of combat deaths, the mortality of surgical exploration paradoxically increased to 53% because more critically injured soldiers survived to receive surgical care.9 Improvements during World War II, such as antibiotics and new surgical techniques, decreased the operative mortality to 24%.10 Modern advances in perioperative care and even faster evacuation with the novel use of the helicopter reduced mortality to 12% in the Korean conflict and 9% during the Vietnam War.10 Many surgeons coming home from World War II brought the dictum of mandatory surgical exploration for all gunshot wounds back to civilian hospitals. Subsequently, during the late 1950s and early 1960s, civilian medical centers began dealing with a proliferation of street violence involving knives and handguns. Urban hospitals were burdened with a volume of patients with penetrating wounds that often overwhelmed the surgical resources, forcing surgeons to triage patients for operation. At the same time, surgeons began to recognize that wounds inflicted by civilian weapons were much less destructive than those caused by military weapons. Last, surgeons were finding that more than 30% of the exploratory laparotomies for civilian penetrating wounds revealed no significant internal organ injury and therefore were unnecessary.11 All of these factors eventually led to a reevaluation of mandatory exploration for penetrating wounds to the abdomen. It was in this context that a selective nonoperative approach to civilian penetrating abdominal wounds was proposed, first by Shaftan11 and then by others.12,13 Experience From the Treatment of Stab Wounds
The historical basis for nonoperative management of gunshot injuries stems from early work in stab injury by Shaftan11 and Nance et al.14 In a 1960 report by Shaftan,11 patients with stab wounds to the anterior abdominal wall were triaged according to the physical examination and basic diagnostic maneuvers such as nasogastric tube insertion, urinalysis, and plain radiographs. It was found that a benign abdominal examination, without associated evidence of hematuria, hematochezia, or free air in the abdomen, essentially excluded intraabdominal injury that would necessitate immediate laparotomy. A later report by Nance et al14 included more than 1,180 patients who either underwent mandatory exploration or a selective nonoperative approach with observation. Of the 432 patients who had manda-
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tory exploration, 53% were found to have absolutely no injuries (ie, negative laparotomy), and 10% were found to have minor injuries that did not require surgical intervention (ie, nontherapeutic laparotomy), which was in contrast to only a 10% negative and 3% nontherapeutic rate in the 126 patients treated with a selective nonoperative approach. In addition, he found that the overall complication rate was higher in the mandatory laparotomy group (13.9%) compared with the selective nonoperative group (6.3%). Most important, in the group that was observed without an operation, only 10 (4%) of 266 patients required a delayed operation for progressing symptoms, with no deaths and only 1 wound infection complication. Several other groups have demonstrated low delayed laparotomy rates15 and low complication rates16 with nonoperative management for stab wounds. In 1996, Leppaniemi and Haapiainen17 presented one of the few prospective randomized trials of nonoperative management of stab wounds. They showed equivalent early mortality with selective nonoperative management compared with mandatory exploration (8% versus 19%; P=.26). In addition, they showed a decreased length of stay and overall cost reduction in patients treated by observation. Four (17%) patients originally randomized to observation required delayed exploration, with no deaths; 1 patient developed an incarcerated diaphragmatic hernia from a missed injury, and 1 patient’s course was complicated by an empyema. C L I N I C A L E X A M I N AT I O N
With gunshot injury, special attention is given to the identification and examination of all surface wounds. Areas that frequently harbor hidden wounds are the axilla, groin, perineum, and gluteal folds. Inspection of the anterior surface will reveal wounds, distention, or evidence of associated trauma such as ecchymosis or abrasions. Most surgeons will avoid palpating directly over wounds because tenderness at the wound site will be confused with deeper, peritoneal pain. Inspection of the surface wound can potentially add information about trajectory, such as a scuff noted on one side of the wound. However, caution should be used when the dermal appearance of gunshot wounds is examined. Using wound characteristics exclusively to rule out deep penetration can be misleading, even for those with significant experience. Skin defects that appear to be superficial can actually be tangential deep wounds. Closely approximated wounds may seem to be connected as a through-and-through wound when they actually represent 2 entrance wounds (Figure 1). Because all gunshot wounds are considered deep penetrating injuries until proven otherwise, local wound exploration, often used in stab wound evaluation, should not be used in gunshot injury.18
Figure 1.
A patient with multiple gunshot wounds to the abdomen. Although the 2 wounds appear to be tangential and caused by the same bullet, they could also represent 2 separate entrance wounds. Caution must be used when trajectory is extrapolated solely on the appearance of surface wounds.
Despite the availability of advanced technologies for the diagnosis of penetrating traumatic injuries, the physical examination remains reliable and sensitive in diagnosing intra-abdominal injury.6,11 Patients with gunshot injury are evaluated in the standard fashion, with attention to airway, breathing, and circulation. Hemodynamically unstable patients are taken directly to the operating room for control of hemorrhage and contamination. Stable patients are evaluated by way of a complete secondary physical examination, which includes a comprehensive abdominal examination. Peritoneal irritation, evidenced by rebound tenderness and nonvoluntary guarding, is evidence of intra-abdominal organ injury and an indication for immediate laparotomy. Injuries that only involve the retroperitoneum may not show signs of peritonitis, even with severe injury. Distracting injuries, such as head trauma or intoxication, may mask signs of peritonitis.
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A common practice is to use plain radiographs of the abdomen as an adjunct to the physical examination. A chest radiograph will allow the trauma team to quickly rule out life-threatening chest injury such as a pneumothorax or hemothorax. If surface wounds are marked with radiopaque markers (eg, paperclips, nipple markers), approximate trajectories may be estimated from lining up markers and projectiles. To determine the position of a projectile in 3-dimensional space, anteroposterior and lateral films should be obtained. In theory, the number of wounds and projectiles found on radiographs should add up to an even number. If this is not the case, additional radiographs are needed to find a missing projectile and a repeated examination should be performed to look for additional wounds. It is important to ask patients whether they have been shot before because retained projectiles from previous injuries can cause confusion. D E T E R M I N AT I O N O F T R A J E C T O R Y
In addition to the physical examination, several adjuncts have been advocated for determining whether a bullet has entered the peritoneal cavity, and if it has, whether a laparotomy is necessary to repair injuries. Some of the most common adjuncts are diagnostic peritoneal lavage, abdominal computed tomography (CT), and laparoscopy. Diagnostic Peritoneal Lavage
Once a very common procedure, diagnostic peritoneal lavage is now used much less frequently in the immediate evaluation of trauma patients.19 However, diagnostic peritoneal lavage has the advantage of being a bedside procedure that can give quick and accurate information about the presence of blood in the peritoneal cavity. Diagnostic peritoneal lavage has been specifically studied as a means of determining peritoneal penetration after gunshot and shotgun wounds. It has been shown to be a sensitive test for blood in the peritoneal cavity but gives no information on specific injuries. Nagy et al20 retrospectively reviewed 429 patients with gunshot wounds in the vicinity of the abdomen but without a definite indication for surgery. By use of a lower-than-normal threshold of 10,000 RBCs/mm3 to define a positive study, 150 patients were found to have a positive examination and underwent laparotomy. All but 6 (96%) had visual confirmation of peritoneal penetration on surgical exploration. Nine (0.5%) patients
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had “negative” lavages but were subsequently explored for either evolving symptoms or injuries found on CT scan or proctoscopy. Similar work by Keleman et al21 in 1997 showed a positive predictive value of 96.7% for diagnostic peritoneal lavage in detecting intra-abdominal injury resulting from a gunshot injury. Diagnostic peritoneal lavage has also been shown to have an 87.5% sensitivity for predicting intra-abdominal injury after shotgun injury to the abdomen.22 Diagnostic peritoneal lavage appears to offer a sensitive means to determine peritoneal penetration and hemoperitoneum. It can be universally applied in all settings and in most patients. In situations in which technology is limited, it provides a safe and inexpensive means to confirm peritoneal penetration. Abdominal CT
Abdominal CT has drastically changed the way blunt trauma is managed in the United States. As image quality and speed of abdominal CT improve, the technology allows accurate, 3-dimensional determination of missile trajectory in penetrating injury. It also clearly defines certain injuries that may not need a laparotomy for repair, such as an isolated liver injury (Figure 2). Grossman et al23 from the Hospital of the University of Pennsylvania reported on the use of CT to determine
Figure 2.
A sagittal CT section through the abdomen showing a trajectory of a gunshot missile through the liver (white arrow). A fragment of the missile is also seen posteriorly (black arrow). This patient was successfully treated nonoperatively.
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trajectory in select, hemodynamically stable individuals with abdominal gunshot wounds. The CT studies were performed on a helical scanner with intravenous and oral contrast. The CT was successful in excluding transperitoneal or transpelvic trajectories in 20 of 37 patients. Of the 17 patients who had a transabdominal or transpelvic trajectory confirmed by abdominal CT, 9 underwent laparotomy, with 1 (11%) nontherapeutic laparotomy. Four patients had isolated solid organ injuries identified on abdominal CT that did not require exploration. The last 4 patients had a transpelvic trajectory that did not involve the rectum, bladder, or prostate and did not undergo exploration. Thus, the abdominal CT enabled 8 patients with documented intraperitoneal or intrapelvic trajectories to avoid laparotomy. These patients were highly selected in that they accounted for less than 2% of all gunshot wounds evaluated by surgeons during the study period. There were no complications or delayed laparotomies. These findings are supported by a subsequent study that successfully used abdominal CT as an initial screening test to exclude transperitoneal penetration in 53 of 83 abdominal gunshot victims.24 Of the 30 patients with proven or potential peritoneal penetration, 4 (13%) patients had intra-abdominal injuries that were successfully managed nonoperatively, and 9 (30%) patients had penetration excluded with a subsequent laparoscopy or thoracoscopy. Chiu et al25 in 2001 used triple-contrast abdominal CT to screen patients with both stab and gunshot injuries. Of the 49 patients with abdominal CT showing no peritoneal penetration (defined as no free air, fluid, contrast leak, or solid organ injury), 47 (96%) patients were successfully treated nonoperatively, 1 (2%) patient had a therapeutic delayed laparotomy, and 1 patient had a delayed nontherapeutic laparotomy. The single missed injury was a diaphragm perforation that required repair.25 CT can add valuable information in select hemodynamically stable patients with gunshot wounds to the abdomen and can rapidly and accurately determine trajectory and the need for laparotomy.
abdominal contents. The procedure allows examination of the anterior intra-abdominal structures in a minimally invasive fashion. It has a potential advantage over standard open laparotomy in that the incisions are smaller, allowing quicker recovery time, less pain, and shorter postoperative hospital stays.27 The limitations are that the entire abdominal cavity, especially the retroperitoneum and posterior diaphragm, cannot be adequately visualized with the laparoscope. In addition, it is difficult to visualize all aspects of the small and large bowel, and subtle injuries to these structures can easily be missed. Thus, the indication for laparoscopy after penetrating trauma is reserved for determining whether there has been peritoneal penetration. If a peritoneal wound is found during laparoscopy, a laparotomy should be performed to fully explore the abdominal contents and repair injuries.27 If no peritoneal penetration is found, an unnecessary open laparotomy is avoided. In a retrospective, multicenter study from 3 institutions with expertise in laparoscopy for trauma, the records of 510 patients undergoing the procedure as part of the initial evaluation for penetrating abdominal trauma were reviewed.28 Of these, 194 were for gunshot wounds, and the remainder were stab wounds. Laparoscopy assisted in determining the absence of peritoneal penetration in 113 (58%) gunshot wounds. Explorations performed on the remaining 81 gunshot wounds with peritoneal penetration resulted in only 15 nontherapeutic explorations, the most frequent sites of injury being the diaphragm, liver, and spleen. At laparotomy, some patients were found to have bowel injuries and injuries to retroperitoneal structures that were missed during the initial laparoscopic portion of the exploration, which confirms that although laparoscopy is a valuable diagnostic tool to determine peritoneal or diaphragmatic penetration, it is not adequate to fully explore the intraabdominal organs after penetrating injury.
Laparoscopy
Abdomen
Laparoscopic techniques are being used with greater frequency for the diagnosis and management of traumatic injuries.26 Although laparoscopy is an operative intervention, it has a role in limiting the need for a full laparotomy in some patients with gunshot injury. Currently, the method requires insufflation of the abdominal cavity, and thus general anesthesia, to visualize the
Two studies from the early 1990s, both from South Africa, confirmed that selected patients with abdominal gunshot wounds could be treated without laparotomy. Muckart et al29 performed a prospective trial of 111 patients with civilian gunshot wounds to the abdomen. A vast majority (80%) of patients had clinical symptoms of peritonitis and were taken directly to the oper-
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ating room. Twenty-two (20%) patients were selected for and none required a delayed laparotomy. Among the patients who were observed, 8 were believed to have negative physical examination results, even with indirect evidence of peritoneal penetration (ie, trajectory by surface wounds). The negative and nontherapeutic laparotomy rates were 5% and 1%, respectively. Selection was made entirely on physical examination and plain radiograph criteria; advanced technologies such as CT and ultrasonography were not used. Demetriades et al6 confirmed the utility of physical examination to determine intra-abdominal injury in a prospective study of 146 patients with abdominal gunshot wounds. Again, the majority (72%) of patients had a positive clinical examination result on admission, prompting immediate exploration. Of the 41 patients (28%) who were observed, 7 eventually underwent delayed laparotomy, with no attributed morbidity or mortality. In a follow-up study at the Los Angeles County Hospital, results were similar, with 59.9% of patients undergoing immediate surgery and 14 of the 106 (13%) patients selected for observation requiring delayed laparotomy. There were 2 complications, a psoas abscess and a respiratory failure that may have been attributed to the delay in treatment, but no deaths.7 In the largest series of nonoperative management of abdominal gunshot wounds, 1,856 patients from the Los Angeles/University of Southern California medical center were evaluated during an 8-year period.30 A total of 792 (42%) patients were initially triaged to nonoperative observation, of whom 712 were eventually discharged without an operation. Of the 80 patients who failed nonoperative treatment and had a delayed laparotomy, 57 had injuries requiring repair. Although the primary triage tool was the physical examination, the majority of patients chosen for nonoperative treatment also had a CT scan performed. The combined negative and nontherapeutic laparotomy rate was 13% in patients undergoing immediate exploration and 29% in those receiving a delayed operation. There were 5 complications—3 intra-abdominal abscesses, 1 ileus, and 1 acute respiratory distress syndrome—that were attributed to a delay in treatment among the 80 patients and necessitated delayed exploration, but no deaths. These studies support the physical examination as a sensitive indicator of intra-abdominal injury after penetrating trauma.
margins bilaterally31 (Figure 3). The area represents a space that can be filled by thoracic and abdominal contents. The difficulty in determining trajectory in this region is partly caused by the motion of the diaphragm and the constantly changing relationship of the internal structures with surface landmarks. The right side of the region is mostly occupied by the liver, whereas the left side contains the spleen, stomach, colon, and small bowel. Because of these anatomic relationships, injuries to the region are treated differently, depending on which side the injury is found in. Isolated penetrating injuries to the right thoracoabdomen will generally involve the liver and diaphragm. Although it has been argued that diaphragm injuries to the right side are less severe because the liver acts to obturate the defect and prevent late herniation of bowel contents, this may not be true.32 Overall, right thoracoabdomen gunshot injury accounts for less than 7% of all abdominal gunshot wounds seen during one study.4 A nonoperative approach to this specific injury has evolved from the frustration of operating on nonbleeding injuries confined to the liver. A group from Grady
Figure 3.
A schematic representation of the anatomic area of the thoracoabdomen. This region extends from the nipple line superiorly, the subcostal margin inferiorly, and to the anterior axillary line bilaterally.
Thoracoabdominal Wounds
The thoracoabdomen is a clinical region of the anatomy that spans from the nipple line to the costal
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Memorial Hospital treated 13 consecutive patients with single gunshot wounds to the right thoracoabdomen nonoperatively after determining trajectory with abdominal CT.4 The majority of patients had both a chest injury (hemothorax, pulmonary contusion) and a solid organ injury (liver, kidney). The chest injuries were treated with tube thoracostomy only, and the solid organ injuries were observed without the need for intervention. In another series of 33 patients with right thoracoabdominal wounds treated nonoperatively, only 1 underwent a laparotomy for worsening clinical symptoms, which proved to be nontherapeutic.33 In another series, a cohort of 16 hemodynamically stable patients with a right thoracoabdominal gunshot injury were treated nonoperatively after evaluation with abdominal CT.34 In this group, 5 patients had delayed laparotomy for developing peritonitis4 or abdominal compartment syndrome.1 In the remaining 11 patients treated nonoperatively, 1 patient developed a biloma that was treated with percutaneous drainage. In contrast to the right side, injury to the left thoracoabdomen has a higher concern for diaphragm and hollow visceral injury. Because abdominal CT is not sensitive or specific for determining diaphragmatic injury, other methods must be used.35 Murray et al36 reported the incidence of diaphragm injuries with left thoracoabdominal gunshot injury at 42%, much higher than previously appreciated. In this study, all patients underwent diagnostic laparoscopy to rule out diaphragmatic injury. In patients who were found to have a diaphragmatic defect, 31% had no signs of peritonitis and 40% had a normal chest radiograph result. From these findings, the authors recommend diagnostic laparoscopy for all patients with left thoracoabdomen gunshot injury.
peritoneal irritation to be delayed or missing altogether. Last, some adjuncts, such as laparoscopy and diagnostic peritoneal lavage, are of limited value in evaluating the retroperitoneal space. Abdominal CT has been shown to be sensitive and specific for diagnosing wounds in this area and is considered the test of choice for wounds thought to be limited to the retroperitoneum. A variation of the standard CT scan is one performed with “triple contrast.” In addition to the standard oral and intravenous contrast, soluble contrast is placed into the colon by way of an enema. Proponents of this type of preparation believe that it will help identify subtle injury to the retroperitoneal colon. The disadvantages are the inconvenience, delay that the preparation necessitates, and cost. Injuries to the colon by posterior wounds are rare, comprising only 1% of a series of 119 patients at risk for the injury.38 After review of 145 patients with posterior stab wounds, Kirton et al39 failed to find a single patient in which colonic contrast helped to identify an injury.
Figure 4.
A schematic representation of the anatomic area of the flank. This region extends from the anterior axillary line to the posterior axillary line bilaterally. It is bounded superiorly by the tip of the scapula and inferiorly by the iliac crest.
The Back and Flank
The surface landmarks for the flank region include the tips of the scapulas superiorly, the iliac crest inferiorly, the anterior axillary line and the posterior axillary line37 (Figure 4). The back region is bounded by the posterior axillary line bilaterally, the scapular tip superiorly, and the iliac crest inferiorly. Evaluating patients with injuries to these areas is especially difficult. First, there is a paucity of literature supporting nonoperative management in this area, and studies that do exist have small numbers of patients. Also, there is the clinical problem of penetrating injuries involving only the retroperitoneum, which can cause the classic signs of
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Velmahos et al,40 in a study from Los Angeles County Hospital, reviewed their experience with back and flank gunshot wounds. According to clinical examination alone, without abdominal CT or diagnostic peritoneal lavage, patients were selected for nonoperative treatment. Overall, 130 (69%) of the 206 patients studied were treated by observation. There were 4 (3%) delayed laparotomies, all of which were nontherapeutic. The authors conclude that selective nonoperative management of back and flank gunshot wounds is appropriate and safe. Ginzburg et al24 used abdominal CT to characterize 45 gunshot injuries to the flank. Of these, 40 patients had negative abdominal CT results, were observed for 24 hours, and had no delayed laparotomies or complications.
Physiology and Anatomy
Patients with hemodynamic instability or physical examination evidence for peritonitis after a gunshot injury are excluded from nonoperative treatment. Those who are stable and without peritonitis may still harbor an intrabdominal injury that has not yet presented itself. When a patient is evaluated for possible nonoperative management, 2 questions must be asked. First, did the projectile enter the peritoneal, retroperitoneal, or pelvic cavity? And second, if it did, is there an injury that will require a laparotomy to repair? Accurate determination of the projectile trajectory can help answer both of these questions. Thus, the decision about whether a patient can be offered nonoperative care depends on the clinical examination and determination of trajectory.
The Pelvis
The pelvis is an anatomically restricted space with densely crowded internal structures. DiGiacomo et al41 from the University of Pennsylvania showed that transpelvic penetrating injuries have an 85% chance of causing an internal organ injury. However, this group was able to use a selective nonoperative approach similar to the one used in abdominal and back wounds. Unique adjuncts in pelvic injury included urinalysis to diagnose injury to the urethra and bladder and rigid proctoscopy to identify rectal injury. Hematuria or hematochezia are both clinical findings that have a high predictive value of pelvic organ injury.41 Velmahos et al42,43 applied a selective operative approach in place at his institution to evaluate 59 patients with pelvic or gluteal gunshot wounds. According to physical examination, adjunct examinations, and in some cases CT scan, 40 (67.8%) patients were able to be treated nonoperatively. There were no delayed explorations in this group. The authors conclude that the clinical examination alone was 100% sensitive and 95.3% specific for identifying internal organ after pelvic gunshot wounds. PAT I E N T S E L E C T I O N I N T H E E D
Although the emergency physician has an active role in the initial resuscitation of patients with penetrating injury, a surgeon must always be involved with decisions about when to offer operative versus nonoperative management. When determining whether a patient is a candidate for nonoperative treatment, several factors need to be considered by the trauma team.
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Resources
In addition to patient physiology, the ability to perform repeated examinations needs to be considered when a patient with a penetrating injury is observed. If the patient will be unable to have a reliable examination because of head injury, spinal cord injury, sedation, or other factors, nonoperative strategies are impossible. The nonoperative approach also requires that an experienced surgeon be available for repeated examinations, which may not always be possible in a busy trauma center where physicians are dedicated to many other patients, or in smaller hospitals with limited staff. If these issues cannot be satisfactorily addressed, this method of management should not be attempted. Type of Weapon
There are several factors that differentiate penetrating military and civilian wounds. Civilian injuries tend to be caused by handguns with low-caliber missiles and with muzzle velocities between 800 and 1,400 ft/s.44 Typically, these weapons cause a relatively small wound associated with minimal damage caused by blast or cavitation effect. Tissue destruction is limited to a small area around the missile path. Thus, usually only organs directly in the path of the projectile will be injured.44 In contrast, blast injury and cavitation are more important with high-velocity missiles, such as those delivered by rifles and military weapons, or in shotgun wounds.45 These projectiles cause much more widespread tissue destruction along a missile path significantly wider than the actual projectile (Figure 5). The tissue destruction often involves large areas of necrosis, and thus most surgeons would explore and debride these
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wounds, even without signs of peritonitis or evidence of peritoneal penetration. In conclusion, although there is growing evidence that selective nonoperative management of some penetrating injuries to the abdomen, flank, back, and pelvis may be safe, care must be taken in analyzing the available evidence. Many of the studies are small and have wide confidence intervals. In addition, the majority of the larger studies are from only a few groups of trauma surgeons who practice in some of the busiest trauma centers in the country. Thus, the success in these urban, Level I centers may not be immediately transferable to hospitals with less experience in penetrating injury or with more limited resources. There are several other reasons why this type of approach may not be immediately applicable to all institutions. This type of approach is applied to only a small percentage of patients, and the vast majority of patients with penetrating injury will need immediate operative exploration. Thus, if a center cares for only 10 to 20 penetrating patients annually, only 1 or 2 patients a year may qualify for this type of treatment. A small
Figure 5.
Wounds caused by a highly destructive weapon, in this case a shotgun. Notice the large wounds with extensive tissue damage. Patients with gunshot injury from highly destructive weapons, such as a rifle, military weapon, or shotgun, are often excluded from nonoperative treatment strategies.
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census of gunshot injuries may not allow the practitioners to develop the mature judgment that comes from extensive experience in treating patients with penetrating injury. In addition, nonoperative approaches require continuous evaluation by an experienced surgeon and necessitate a system that can provide ongoing monitoring and scrutiny. Thus, further studies, including involvement of Level II and III trauma centers, will be needed to determine the universality of this type of management for gunshot injury. Author contributions: PMR conceived of the study. JPP drafted the manuscript. GPD and MDG provided literature review; GPD provided figures. CWS contributed to editing of the manuscript and provided information on wounding patterns and imaging. PMR, GPD, and MDG contributed to the final revision. JPP takes responsibility for the paper as a whole. Received for publication November 22, 2002. Revisions received June 10, 2003, and July 7, 2003. Accepted for publication August 7, 2003. The authors report this study did not receive any outside funding or support. Reprints not available from the authors. Address for correspondence: John P. Pryor, MD, Division of Traumatology and Surgical Critical Care, 3440 Market Street, Philadelphia, PA 19104; 215-662-7323, fax 215-614-0375; E-mail [email protected]. edu.
REFERENCES 1. Nance ML, Nance FC. It is time we told the emperor about his clothes. J Trauma. 1996;40:185-186. 2. Renz B, Feliciano DV. Unnecessary laparotomies for trauma: a prospective study of morbidity. J Trauma. 1995;38:350-356. 3. Weigelt JA, Kingman RG. Complications of negative laparotomy for trauma. Am J Surg. 1988;156:544-547. 4. Renz BM, Feliciano DV. The length of hospital stay after an unnecessary laparotomy for trauma: a prospective study. J Trauma. 1996;40:187-190. 5. Easter DW, Shackford SR, Mattrey RF. A prospective randomized comparison of computed tomography with conventional diagnostic methods in the evaluation of penetrating injuries to the back and flank. Arch Surg. 1991;126:115-118. 6. Demetriades D, Charalambides D, Lakhoo M, et al. Gunshot wounds of the abdomen: role of selective conservative management. Br J Surg. 1991;78:220-222. 7. Demetriades D, Velmahos G, Cornwell E, et al. Selective nonoperative management of gunshot wounds of the anterior abdomen. Arch Surg. 1997;132:178-183. 8. Otis GA. The Medical and Surgical History of the War of the Rebellion: Surgical History. Part II, vol. II. Washington, DC: US Government Printing Office; 1877. 9. Bailey H, ed. Surgery of Modern Warfare. Vol. II, 3rd ed. Baltimore, MD: Williams & Wilkins; 1944. 10. Adams DB. Abdominal gunshot wounds in warfare: a historical review. Mil Med. 1983;143:15-19. 11. Shaftan GW. Indications for operation in abdominal trauma. Am J Surg. 1960;99:657-664. 12. Maynard A, Orpeza G. Mandatory operation for penetrating wounds to the abdomen. Am J Surg. 1968;115:307-312. 13. Bull JC, Mathewson C. Exploratory laparotomy in patients with penetrating wounds of the abdomen. Am J Surg. 1968;116:223-227. 14. Nance F, Wennar M, Johnson L, et al. Surgical judgment in the management of penetrating wounds of the abdomen. Ann Surg. 1974;179:639-646. 15. Demetriades D, Rabinowitz B. Indications for operation in abdominal stab wounds. Ann Surg. 1986;205:129-132.
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16. Robin AP, Andrews JR, Lange DA, et al. Selective management of anterior abdominal stab wounds. J Trauma. 1989;29:1684-1689. 17. Leppaniemi AK, Haapiainen RK. Selective nonoperative management of abdominal stab wounds: prospective, randomised study. World J Surg. 1996;20:1101-1106. 18. Moore EE, Marx JA. Penetrating abdominal wounds: rationale for exploratory laparotomy. JAMA. 1985;253:2705-2708. 19. Fakhry SM. The resident experience on trauma: declining surgical opportunities and career incentive? data from a large multi-institutional study. J Trauma. 2003;54:1-7. 20. Nagy KK, Krosner SM, Joseph KT, et al. A method of determining peritoneal penetration in gunshot wounds to the abdomen. J Trauma. 1997;43:242-246. 21. Keleman JJ, Martin R, Obney JA, et al. Evaluation of diagnostic peritoneal lavage in stable patients with gunshot wounds to the abdomen. Arch Surg. 1997;132:909-913. 22. Brakenridge SC, Nagy KK, Joseph KT, et al. Detection of intra-abdomial injury using diagnostic peritoneal lavage after shotgun wound to the abdomen. J Trauma. 2003;54:329-331. 23. Grossman MD, May AK, Schwab CW, et al. Determining anatomic injury with computed tomography in selected torso gunshot wounds. J Trauma. 1996;45:446-456. 24. Ginzburg E, Carillo EH, Kopelman T, et al. The role of computed tomography in selective management of gunshot wounds to the abdomen and flank. J Trauma. 1998;45:1005-1009. 25. Chiu WC, Shanmuganathan K, Mirvis SE, et al. Determining the need for laparotomy in penetrating torso trauma: a prospective study using triple contrast enhanced abdomiopelvic computed tomography. J Trauma. 2001;51:860-869. 26. Ivatury RR, Simon RJ, Weksler B, et al. Laparoscopy in the evaluation of the intrathoracic abdomen after penetrating injury. J Trauma. 1992;33:101-109. 27. Ditmars ML, Bongard F. Laparoscopy for triage of penetrating trauma: the decision to explore. J Laparoendosc Surg. 1996;6:285-291. 28. Zantut LF, Ivatury RR, Smith RS, et al. Diagnostic and therapeutic laparoscopy for penetrating abdominal trauma: a multi-center experience. J Trauma. 1997;42:825-831. 29. Muckart DJ, Abdool-Carrim ATO, King B. Selective conservative management of abdominal gunshot wounds: a prospective study. Br J Surg. 1990;77:652-655. 30. Velmahos GC, Demetriades D, Toutouzas KG, et al. Selective nonoperative management in 1,856 patients with abdominal gunshot wounds: should routine laparotomy still be the standard of care. Ann Surg. 2001;234:395-403. 31. Renz B, Feliciano DV. Gunshot wounds to the right thoracoabdomen: a prospective study of nonoperative management. J Trauma. 1994;37:737-744. 32. Zierold D, Perlstein J, Weidman ER, et al. Penetrating trauma to the diaphragm: natural history and ultrasonagraphic characteristics of untreated injury in the pig model. Arch Surg. 2001;136:32-37. 33. Chmielewski GW, Nicholas JM, Dulchavsky SA, et al. Nonoperative management of gunshot wounds of the abdomen. Am Surg. 1995;61:665-668. 34. Demetriades D, Gomez H, Chahwan S, et al. Gunshot wounds to the liver: the role of selective nonoperative management. J Am Coll Surg. 1999;188:343-348. 35. Guth AA, Patcher HL, Kim U. Pitfalls in the diagnosis of diaphragmatic injury. Am J Surg. 1995;170:5-9. 36. Murray JA, Demetriades D, Cornwell EE, et al. Penetrating left thoracoabdominal trauma: the incidence and clinical presentation of diaphragm injuries. J Trauma. 1997;43:624-626. 37. Boyle EM, Maier RV, Salazar JD, et al. Diagnosis of injuries after stab wounds to the back and flank. J Trauma. 1997;42:260-265. 38. Phillips T, Scalafani SJA, Goldstein A, et al. Use of contrast enhanced CT enema in the management of penetrating trauma to the flank and back. J Trauma. 1986;26:593-596. 39. Kirton OC, Wint D, Thrasher B, et al. Stab wounds to the back and flank in the hemodynamically stable patient: a decision algorithm based on contrast-enhanced computed tomography with colonic opacification. Am J Surg. 1997;173:189-193. 40. Velmahos GC, Demetriades D, Foianini E, et al. A selective approach to the management of gunshot wounds to the back. Am J Surg. 1997;174:342-346. 41. DiGiacomo JC, Schwab CW, Rotondo MF, et al. Gluteal gunshot wounds: who warrants exploration? J Trauma. 1994;37:622-628. 42. Velmahos GC, Demetriades D, Cornwell EE, et al. Gunshot wounds to the buttocks: predicting the need for operation. Dis Col Rectum. 1997;40:307-311. 43. Velmahos GC, Demetriades D, Cornwell EE. Transpelvic gunshot wounds: routine laparotomy or selective management? World J Surg. 1998;22:1034-1038. 44. Bellamy RF, Zajtchuk R, eds. Conventional Warfare: Ballistic, Blast and Burn Injuries. Washington, DC: Office of the Surgeon General, Department of the Army; 1990. 45. Swan KG, Swan RC. Principles of ballistics applicable to the treatment of gunshot wounds. Surg Clin North Am. 1991;71:221-239.
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Nonoperative Management of Abdominal Gunshot Wounds
John P. Pryor, MD Patrick M. Reilly, MD G. Paul Dabrowski, MD Michael D. Grossman, MD C. William Schwab, MD From the Division of Traumatology and Surgical Critical Care, Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA (Pryor, Reilly, Dabrowski, Schwab); and the Division of Trauma and Critical Care, St. Lukes Regional Medical Center, Bethlehem, PA (Grossman).
Mandatory surgical exploration for gunshot wounds to the abdomen has been a surgical dictum for the greater part of this past century. Although nonoperative management of blunt solid organ injuries and low-energy penetrating injuries such as stab wounds is well established, the same is not true for gunshot wounds. The vast majority of patients who sustain a gunshot injury to the abdomen require immediate laparotomy to control bleeding and contain contamination. Nonoperative treatment of patients with a gunshot injury is gaining acceptance in only a highly selected subset of hemodynamically stable adult patients without peritonitis. Although the physical examination remains the cornerstone in the evaluation of patients with gunshot injury, other techniques such as computed tomography, diagnostic peritoneal lavage, and laparoscopy allow accurate determination of intra-abdominal injury. The ability to exclude internal organ injury nonoperatively avoids the potential complications of unnecessary laparotomy. Clinical data to support selective nonoperative management of certain gunshot injuries to the abdomen are accumulating, but the approach has risks and requires careful collaborative management by emergency physicians and surgeons experienced in the care of penetrating injury. [Ann Emerg Med. 2004;43:344-353.]
INTRODUCTION
0196-0644/$30.00 Copyright © 2004 by the American College of Emergency Physicians. doi:10.1016/mem.2004.422
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The vast majority of patients who sustain a gunshot injury to the abdomen require immediate laparotomy to control bleeding and contain contamination. These patients often present with hemodynamic instability or a physical examination consistent with peritonitis. Nonoperative treatment of patients with a gunshot injury is gaining acceptance in only a highly selected subset of patients without these findings. If the appropriate patients can be identified, however, many unnecessary laparotomies, along with the associated complications, can be avoided. In many ways, nonoperative care for patients with gunshot injury mirrors the recent trends in nonoperative management of other types of traumatic injury. Although nonoperative management of blunt solid organ injuries and low-energy penetrating injuries such as stab wounds is well established, the same is not true for gunshot wounds. Unlike stab injuries, gunshot injuries produce deeper wounding and more tissue destruction and often have unclear trajectories that confuse the anatomic diagnosis. Although the evidence for selective nonoperative management of
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gunshot injuries to the abdomen, back, flank, and pelvis is accumulating, the approach requires mature judgment, experience, and a multimodal approach by emergency physicians and surgeons working together to determine which patients can be treated safely.1 Nonoperative management is attractive because it avoids the morbidity and potential mortality of an unnecessary laparotomy. Unnecessary operations include those in which the surgeon fails to find any injury in the peritoneal, pelvic, or retroperitoneal cavities (ie, negative laparotomy) or finds only minor injuries that do not need surgical repair, such as a nonbleeding liver laceration (ie, nontherapeutic laparotomy). The morbidity of an unnecessary laparotomy has been reported to be as high as 41.3% when problems such as atelectasis, prolonged ileus, and urinary tract infections are included2 to as low as 2.5% when only major complications such as subsequent small bowel obstruction are considered.3 In addition, an unnecessary laparotomy increases the hospital length of stay4 and significantly increases the cost of care.5 Conversely, delayed exploration and treatment of an intra-abdominal injury can cause complications. Surgeons have long advocated mandatory exploration specifically to avoid the morbidity or mortality related to any delay in treatment of a missed intra-abdominal injury. Several recent studies suggest that, in fact, there is no significant increase in complications resulting from a delayed operative procedure in patients who initially lacked positive clinical signs,6,7 which assumes that a change in the physical examination is identified within a reasonable period (<24 hours). Thus, if no immediate indication for operation exists, patients can be safely observed for the development of physical findings that may warrant surgical exploration. HISTORICAL PERSPECTIVE Experience From War
Penetrating trauma has been treated nonoperatively for the greater part of human existence, primarily because surgery was not technologically possible with any real success.8 This method significantly changed during the modern era of surgery, which began after the introduction of anesthesia in 1846. With advances in anesthesia, antisepsis, instrumentation, and surgical technique, surgeons at the beginning of World War I had the ability to perform trauma laparotomies with relative safety. At the same time, soldiers learned to evacu-
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ate the combat injured quickly to field hospitals where surgery could be performed. Although this procedure led to a lower overall number of combat deaths, the mortality of surgical exploration paradoxically increased to 53% because more critically injured soldiers survived to receive surgical care.9 Improvements during World War II, such as antibiotics and new surgical techniques, decreased the operative mortality to 24%.10 Modern advances in perioperative care and even faster evacuation with the novel use of the helicopter reduced mortality to 12% in the Korean conflict and 9% during the Vietnam War.10 Many surgeons coming home from World War II brought the dictum of mandatory surgical exploration for all gunshot wounds back to civilian hospitals. Subsequently, during the late 1950s and early 1960s, civilian medical centers began dealing with a proliferation of street violence involving knives and handguns. Urban hospitals were burdened with a volume of patients with penetrating wounds that often overwhelmed the surgical resources, forcing surgeons to triage patients for operation. At the same time, surgeons began to recognize that wounds inflicted by civilian weapons were much less destructive than those caused by military weapons. Last, surgeons were finding that more than 30% of the exploratory laparotomies for civilian penetrating wounds revealed no significant internal organ injury and therefore were unnecessary.11 All of these factors eventually led to a reevaluation of mandatory exploration for penetrating wounds to the abdomen. It was in this context that a selective nonoperative approach to civilian penetrating abdominal wounds was proposed, first by Shaftan11 and then by others.12,13 Experience From the Treatment of Stab Wounds
The historical basis for nonoperative management of gunshot injuries stems from early work in stab injury by Shaftan11 and Nance et al.14 In a 1960 report by Shaftan,11 patients with stab wounds to the anterior abdominal wall were triaged according to the physical examination and basic diagnostic maneuvers such as nasogastric tube insertion, urinalysis, and plain radiographs. It was found that a benign abdominal examination, without associated evidence of hematuria, hematochezia, or free air in the abdomen, essentially excluded intraabdominal injury that would necessitate immediate laparotomy. A later report by Nance et al14 included more than 1,180 patients who either underwent mandatory exploration or a selective nonoperative approach with observation. Of the 432 patients who had manda-
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tory exploration, 53% were found to have absolutely no injuries (ie, negative laparotomy), and 10% were found to have minor injuries that did not require surgical intervention (ie, nontherapeutic laparotomy), which was in contrast to only a 10% negative and 3% nontherapeutic rate in the 126 patients treated with a selective nonoperative approach. In addition, he found that the overall complication rate was higher in the mandatory laparotomy group (13.9%) compared with the selective nonoperative group (6.3%). Most important, in the group that was observed without an operation, only 10 (4%) of 266 patients required a delayed operation for progressing symptoms, with no deaths and only 1 wound infection complication. Several other groups have demonstrated low delayed laparotomy rates15 and low complication rates16 with nonoperative management for stab wounds. In 1996, Leppaniemi and Haapiainen17 presented one of the few prospective randomized trials of nonoperative management of stab wounds. They showed equivalent early mortality with selective nonoperative management compared with mandatory exploration (8% versus 19%; P=.26). In addition, they showed a decreased length of stay and overall cost reduction in patients treated by observation. Four (17%) patients originally randomized to observation required delayed exploration, with no deaths; 1 patient developed an incarcerated diaphragmatic hernia from a missed injury, and 1 patient’s course was complicated by an empyema. C L I N I C A L E X A M I N AT I O N
With gunshot injury, special attention is given to the identification and examination of all surface wounds. Areas that frequently harbor hidden wounds are the axilla, groin, perineum, and gluteal folds. Inspection of the anterior surface will reveal wounds, distention, or evidence of associated trauma such as ecchymosis or abrasions. Most surgeons will avoid palpating directly over wounds because tenderness at the wound site will be confused with deeper, peritoneal pain. Inspection of the surface wound can potentially add information about trajectory, such as a scuff noted on one side of the wound. However, caution should be used when the dermal appearance of gunshot wounds is examined. Using wound characteristics exclusively to rule out deep penetration can be misleading, even for those with significant experience. Skin defects that appear to be superficial can actually be tangential deep wounds. Closely approximated wounds may seem to be connected as a through-and-through wound when they actually represent 2 entrance wounds (Figure 1). Because all gunshot wounds are considered deep penetrating injuries until proven otherwise, local wound exploration, often used in stab wound evaluation, should not be used in gunshot injury.18
Figure 1.
A patient with multiple gunshot wounds to the abdomen. Although the 2 wounds appear to be tangential and caused by the same bullet, they could also represent 2 separate entrance wounds. Caution must be used when trajectory is extrapolated solely on the appearance of surface wounds.
Despite the availability of advanced technologies for the diagnosis of penetrating traumatic injuries, the physical examination remains reliable and sensitive in diagnosing intra-abdominal injury.6,11 Patients with gunshot injury are evaluated in the standard fashion, with attention to airway, breathing, and circulation. Hemodynamically unstable patients are taken directly to the operating room for control of hemorrhage and contamination. Stable patients are evaluated by way of a complete secondary physical examination, which includes a comprehensive abdominal examination. Peritoneal irritation, evidenced by rebound tenderness and nonvoluntary guarding, is evidence of intra-abdominal organ injury and an indication for immediate laparotomy. Injuries that only involve the retroperitoneum may not show signs of peritonitis, even with severe injury. Distracting injuries, such as head trauma or intoxication, may mask signs of peritonitis.
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A common practice is to use plain radiographs of the abdomen as an adjunct to the physical examination. A chest radiograph will allow the trauma team to quickly rule out life-threatening chest injury such as a pneumothorax or hemothorax. If surface wounds are marked with radiopaque markers (eg, paperclips, nipple markers), approximate trajectories may be estimated from lining up markers and projectiles. To determine the position of a projectile in 3-dimensional space, anteroposterior and lateral films should be obtained. In theory, the number of wounds and projectiles found on radiographs should add up to an even number. If this is not the case, additional radiographs are needed to find a missing projectile and a repeated examination should be performed to look for additional wounds. It is important to ask patients whether they have been shot before because retained projectiles from previous injuries can cause confusion. D E T E R M I N AT I O N O F T R A J E C T O R Y
In addition to the physical examination, several adjuncts have been advocated for determining whether a bullet has entered the peritoneal cavity, and if it has, whether a laparotomy is necessary to repair injuries. Some of the most common adjuncts are diagnostic peritoneal lavage, abdominal computed tomography (CT), and laparoscopy. Diagnostic Peritoneal Lavage
Once a very common procedure, diagnostic peritoneal lavage is now used much less frequently in the immediate evaluation of trauma patients.19 However, diagnostic peritoneal lavage has the advantage of being a bedside procedure that can give quick and accurate information about the presence of blood in the peritoneal cavity. Diagnostic peritoneal lavage has been specifically studied as a means of determining peritoneal penetration after gunshot and shotgun wounds. It has been shown to be a sensitive test for blood in the peritoneal cavity but gives no information on specific injuries. Nagy et al20 retrospectively reviewed 429 patients with gunshot wounds in the vicinity of the abdomen but without a definite indication for surgery. By use of a lower-than-normal threshold of 10,000 RBCs/mm3 to define a positive study, 150 patients were found to have a positive examination and underwent laparotomy. All but 6 (96%) had visual confirmation of peritoneal penetration on surgical exploration. Nine (0.5%) patients
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had “negative” lavages but were subsequently explored for either evolving symptoms or injuries found on CT scan or proctoscopy. Similar work by Keleman et al21 in 1997 showed a positive predictive value of 96.7% for diagnostic peritoneal lavage in detecting intra-abdominal injury resulting from a gunshot injury. Diagnostic peritoneal lavage has also been shown to have an 87.5% sensitivity for predicting intra-abdominal injury after shotgun injury to the abdomen.22 Diagnostic peritoneal lavage appears to offer a sensitive means to determine peritoneal penetration and hemoperitoneum. It can be universally applied in all settings and in most patients. In situations in which technology is limited, it provides a safe and inexpensive means to confirm peritoneal penetration. Abdominal CT
Abdominal CT has drastically changed the way blunt trauma is managed in the United States. As image quality and speed of abdominal CT improve, the technology allows accurate, 3-dimensional determination of missile trajectory in penetrating injury. It also clearly defines certain injuries that may not need a laparotomy for repair, such as an isolated liver injury (Figure 2). Grossman et al23 from the Hospital of the University of Pennsylvania reported on the use of CT to determine
Figure 2.
A sagittal CT section through the abdomen showing a trajectory of a gunshot missile through the liver (white arrow). A fragment of the missile is also seen posteriorly (black arrow). This patient was successfully treated nonoperatively.
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trajectory in select, hemodynamically stable individuals with abdominal gunshot wounds. The CT studies were performed on a helical scanner with intravenous and oral contrast. The CT was successful in excluding transperitoneal or transpelvic trajectories in 20 of 37 patients. Of the 17 patients who had a transabdominal or transpelvic trajectory confirmed by abdominal CT, 9 underwent laparotomy, with 1 (11%) nontherapeutic laparotomy. Four patients had isolated solid organ injuries identified on abdominal CT that did not require exploration. The last 4 patients had a transpelvic trajectory that did not involve the rectum, bladder, or prostate and did not undergo exploration. Thus, the abdominal CT enabled 8 patients with documented intraperitoneal or intrapelvic trajectories to avoid laparotomy. These patients were highly selected in that they accounted for less than 2% of all gunshot wounds evaluated by surgeons during the study period. There were no complications or delayed laparotomies. These findings are supported by a subsequent study that successfully used abdominal CT as an initial screening test to exclude transperitoneal penetration in 53 of 83 abdominal gunshot victims.24 Of the 30 patients with proven or potential peritoneal penetration, 4 (13%) patients had intra-abdominal injuries that were successfully managed nonoperatively, and 9 (30%) patients had penetration excluded with a subsequent laparoscopy or thoracoscopy. Chiu et al25 in 2001 used triple-contrast abdominal CT to screen patients with both stab and gunshot injuries. Of the 49 patients with abdominal CT showing no peritoneal penetration (defined as no free air, fluid, contrast leak, or solid organ injury), 47 (96%) patients were successfully treated nonoperatively, 1 (2%) patient had a therapeutic delayed laparotomy, and 1 patient had a delayed nontherapeutic laparotomy. The single missed injury was a diaphragm perforation that required repair.25 CT can add valuable information in select hemodynamically stable patients with gunshot wounds to the abdomen and can rapidly and accurately determine trajectory and the need for laparotomy.
abdominal contents. The procedure allows examination of the anterior intra-abdominal structures in a minimally invasive fashion. It has a potential advantage over standard open laparotomy in that the incisions are smaller, allowing quicker recovery time, less pain, and shorter postoperative hospital stays.27 The limitations are that the entire abdominal cavity, especially the retroperitoneum and posterior diaphragm, cannot be adequately visualized with the laparoscope. In addition, it is difficult to visualize all aspects of the small and large bowel, and subtle injuries to these structures can easily be missed. Thus, the indication for laparoscopy after penetrating trauma is reserved for determining whether there has been peritoneal penetration. If a peritoneal wound is found during laparoscopy, a laparotomy should be performed to fully explore the abdominal contents and repair injuries.27 If no peritoneal penetration is found, an unnecessary open laparotomy is avoided. In a retrospective, multicenter study from 3 institutions with expertise in laparoscopy for trauma, the records of 510 patients undergoing the procedure as part of the initial evaluation for penetrating abdominal trauma were reviewed.28 Of these, 194 were for gunshot wounds, and the remainder were stab wounds. Laparoscopy assisted in determining the absence of peritoneal penetration in 113 (58%) gunshot wounds. Explorations performed on the remaining 81 gunshot wounds with peritoneal penetration resulted in only 15 nontherapeutic explorations, the most frequent sites of injury being the diaphragm, liver, and spleen. At laparotomy, some patients were found to have bowel injuries and injuries to retroperitoneal structures that were missed during the initial laparoscopic portion of the exploration, which confirms that although laparoscopy is a valuable diagnostic tool to determine peritoneal or diaphragmatic penetration, it is not adequate to fully explore the intraabdominal organs after penetrating injury.
Laparoscopy
Abdomen
Laparoscopic techniques are being used with greater frequency for the diagnosis and management of traumatic injuries.26 Although laparoscopy is an operative intervention, it has a role in limiting the need for a full laparotomy in some patients with gunshot injury. Currently, the method requires insufflation of the abdominal cavity, and thus general anesthesia, to visualize the
Two studies from the early 1990s, both from South Africa, confirmed that selected patients with abdominal gunshot wounds could be treated without laparotomy. Muckart et al29 performed a prospective trial of 111 patients with civilian gunshot wounds to the abdomen. A vast majority (80%) of patients had clinical symptoms of peritonitis and were taken directly to the oper-
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ating room. Twenty-two (20%) patients were selected for and none required a delayed laparotomy. Among the patients who were observed, 8 were believed to have negative physical examination results, even with indirect evidence of peritoneal penetration (ie, trajectory by surface wounds). The negative and nontherapeutic laparotomy rates were 5% and 1%, respectively. Selection was made entirely on physical examination and plain radiograph criteria; advanced technologies such as CT and ultrasonography were not used. Demetriades et al6 confirmed the utility of physical examination to determine intra-abdominal injury in a prospective study of 146 patients with abdominal gunshot wounds. Again, the majority (72%) of patients had a positive clinical examination result on admission, prompting immediate exploration. Of the 41 patients (28%) who were observed, 7 eventually underwent delayed laparotomy, with no attributed morbidity or mortality. In a follow-up study at the Los Angeles County Hospital, results were similar, with 59.9% of patients undergoing immediate surgery and 14 of the 106 (13%) patients selected for observation requiring delayed laparotomy. There were 2 complications, a psoas abscess and a respiratory failure that may have been attributed to the delay in treatment, but no deaths.7 In the largest series of nonoperative management of abdominal gunshot wounds, 1,856 patients from the Los Angeles/University of Southern California medical center were evaluated during an 8-year period.30 A total of 792 (42%) patients were initially triaged to nonoperative observation, of whom 712 were eventually discharged without an operation. Of the 80 patients who failed nonoperative treatment and had a delayed laparotomy, 57 had injuries requiring repair. Although the primary triage tool was the physical examination, the majority of patients chosen for nonoperative treatment also had a CT scan performed. The combined negative and nontherapeutic laparotomy rate was 13% in patients undergoing immediate exploration and 29% in those receiving a delayed operation. There were 5 complications—3 intra-abdominal abscesses, 1 ileus, and 1 acute respiratory distress syndrome—that were attributed to a delay in treatment among the 80 patients and necessitated delayed exploration, but no deaths. These studies support the physical examination as a sensitive indicator of intra-abdominal injury after penetrating trauma.
margins bilaterally31 (Figure 3). The area represents a space that can be filled by thoracic and abdominal contents. The difficulty in determining trajectory in this region is partly caused by the motion of the diaphragm and the constantly changing relationship of the internal structures with surface landmarks. The right side of the region is mostly occupied by the liver, whereas the left side contains the spleen, stomach, colon, and small bowel. Because of these anatomic relationships, injuries to the region are treated differently, depending on which side the injury is found in. Isolated penetrating injuries to the right thoracoabdomen will generally involve the liver and diaphragm. Although it has been argued that diaphragm injuries to the right side are less severe because the liver acts to obturate the defect and prevent late herniation of bowel contents, this may not be true.32 Overall, right thoracoabdomen gunshot injury accounts for less than 7% of all abdominal gunshot wounds seen during one study.4 A nonoperative approach to this specific injury has evolved from the frustration of operating on nonbleeding injuries confined to the liver. A group from Grady
Figure 3.
A schematic representation of the anatomic area of the thoracoabdomen. This region extends from the nipple line superiorly, the subcostal margin inferiorly, and to the anterior axillary line bilaterally.
Thoracoabdominal Wounds
The thoracoabdomen is a clinical region of the anatomy that spans from the nipple line to the costal
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Memorial Hospital treated 13 consecutive patients with single gunshot wounds to the right thoracoabdomen nonoperatively after determining trajectory with abdominal CT.4 The majority of patients had both a chest injury (hemothorax, pulmonary contusion) and a solid organ injury (liver, kidney). The chest injuries were treated with tube thoracostomy only, and the solid organ injuries were observed without the need for intervention. In another series of 33 patients with right thoracoabdominal wounds treated nonoperatively, only 1 underwent a laparotomy for worsening clinical symptoms, which proved to be nontherapeutic.33 In another series, a cohort of 16 hemodynamically stable patients with a right thoracoabdominal gunshot injury were treated nonoperatively after evaluation with abdominal CT.34 In this group, 5 patients had delayed laparotomy for developing peritonitis4 or abdominal compartment syndrome.1 In the remaining 11 patients treated nonoperatively, 1 patient developed a biloma that was treated with percutaneous drainage. In contrast to the right side, injury to the left thoracoabdomen has a higher concern for diaphragm and hollow visceral injury. Because abdominal CT is not sensitive or specific for determining diaphragmatic injury, other methods must be used.35 Murray et al36 reported the incidence of diaphragm injuries with left thoracoabdominal gunshot injury at 42%, much higher than previously appreciated. In this study, all patients underwent diagnostic laparoscopy to rule out diaphragmatic injury. In patients who were found to have a diaphragmatic defect, 31% had no signs of peritonitis and 40% had a normal chest radiograph result. From these findings, the authors recommend diagnostic laparoscopy for all patients with left thoracoabdomen gunshot injury.
peritoneal irritation to be delayed or missing altogether. Last, some adjuncts, such as laparoscopy and diagnostic peritoneal lavage, are of limited value in evaluating the retroperitoneal space. Abdominal CT has been shown to be sensitive and specific for diagnosing wounds in this area and is considered the test of choice for wounds thought to be limited to the retroperitoneum. A variation of the standard CT scan is one performed with “triple contrast.” In addition to the standard oral and intravenous contrast, soluble contrast is placed into the colon by way of an enema. Proponents of this type of preparation believe that it will help identify subtle injury to the retroperitoneal colon. The disadvantages are the inconvenience, delay that the preparation necessitates, and cost. Injuries to the colon by posterior wounds are rare, comprising only 1% of a series of 119 patients at risk for the injury.38 After review of 145 patients with posterior stab wounds, Kirton et al39 failed to find a single patient in which colonic contrast helped to identify an injury.
Figure 4.
A schematic representation of the anatomic area of the flank. This region extends from the anterior axillary line to the posterior axillary line bilaterally. It is bounded superiorly by the tip of the scapula and inferiorly by the iliac crest.
The Back and Flank
The surface landmarks for the flank region include the tips of the scapulas superiorly, the iliac crest inferiorly, the anterior axillary line and the posterior axillary line37 (Figure 4). The back region is bounded by the posterior axillary line bilaterally, the scapular tip superiorly, and the iliac crest inferiorly. Evaluating patients with injuries to these areas is especially difficult. First, there is a paucity of literature supporting nonoperative management in this area, and studies that do exist have small numbers of patients. Also, there is the clinical problem of penetrating injuries involving only the retroperitoneum, which can cause the classic signs of
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Velmahos et al,40 in a study from Los Angeles County Hospital, reviewed their experience with back and flank gunshot wounds. According to clinical examination alone, without abdominal CT or diagnostic peritoneal lavage, patients were selected for nonoperative treatment. Overall, 130 (69%) of the 206 patients studied were treated by observation. There were 4 (3%) delayed laparotomies, all of which were nontherapeutic. The authors conclude that selective nonoperative management of back and flank gunshot wounds is appropriate and safe. Ginzburg et al24 used abdominal CT to characterize 45 gunshot injuries to the flank. Of these, 40 patients had negative abdominal CT results, were observed for 24 hours, and had no delayed laparotomies or complications.
Physiology and Anatomy
Patients with hemodynamic instability or physical examination evidence for peritonitis after a gunshot injury are excluded from nonoperative treatment. Those who are stable and without peritonitis may still harbor an intrabdominal injury that has not yet presented itself. When a patient is evaluated for possible nonoperative management, 2 questions must be asked. First, did the projectile enter the peritoneal, retroperitoneal, or pelvic cavity? And second, if it did, is there an injury that will require a laparotomy to repair? Accurate determination of the projectile trajectory can help answer both of these questions. Thus, the decision about whether a patient can be offered nonoperative care depends on the clinical examination and determination of trajectory.
The Pelvis
The pelvis is an anatomically restricted space with densely crowded internal structures. DiGiacomo et al41 from the University of Pennsylvania showed that transpelvic penetrating injuries have an 85% chance of causing an internal organ injury. However, this group was able to use a selective nonoperative approach similar to the one used in abdominal and back wounds. Unique adjuncts in pelvic injury included urinalysis to diagnose injury to the urethra and bladder and rigid proctoscopy to identify rectal injury. Hematuria or hematochezia are both clinical findings that have a high predictive value of pelvic organ injury.41 Velmahos et al42,43 applied a selective operative approach in place at his institution to evaluate 59 patients with pelvic or gluteal gunshot wounds. According to physical examination, adjunct examinations, and in some cases CT scan, 40 (67.8%) patients were able to be treated nonoperatively. There were no delayed explorations in this group. The authors conclude that the clinical examination alone was 100% sensitive and 95.3% specific for identifying internal organ after pelvic gunshot wounds. PAT I E N T S E L E C T I O N I N T H E E D
Although the emergency physician has an active role in the initial resuscitation of patients with penetrating injury, a surgeon must always be involved with decisions about when to offer operative versus nonoperative management. When determining whether a patient is a candidate for nonoperative treatment, several factors need to be considered by the trauma team.
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In addition to patient physiology, the ability to perform repeated examinations needs to be considered when a patient with a penetrating injury is observed. If the patient will be unable to have a reliable examination because of head injury, spinal cord injury, sedation, or other factors, nonoperative strategies are impossible. The nonoperative approach also requires that an experienced surgeon be available for repeated examinations, which may not always be possible in a busy trauma center where physicians are dedicated to many other patients, or in smaller hospitals with limited staff. If these issues cannot be satisfactorily addressed, this method of management should not be attempted. Type of Weapon
There are several factors that differentiate penetrating military and civilian wounds. Civilian injuries tend to be caused by handguns with low-caliber missiles and with muzzle velocities between 800 and 1,400 ft/s.44 Typically, these weapons cause a relatively small wound associated with minimal damage caused by blast or cavitation effect. Tissue destruction is limited to a small area around the missile path. Thus, usually only organs directly in the path of the projectile will be injured.44 In contrast, blast injury and cavitation are more important with high-velocity missiles, such as those delivered by rifles and military weapons, or in shotgun wounds.45 These projectiles cause much more widespread tissue destruction along a missile path significantly wider than the actual projectile (Figure 5). The tissue destruction often involves large areas of necrosis, and thus most surgeons would explore and debride these
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wounds, even without signs of peritonitis or evidence of peritoneal penetration. In conclusion, although there is growing evidence that selective nonoperative management of some penetrating injuries to the abdomen, flank, back, and pelvis may be safe, care must be taken in analyzing the available evidence. Many of the studies are small and have wide confidence intervals. In addition, the majority of the larger studies are from only a few groups of trauma surgeons who practice in some of the busiest trauma centers in the country. Thus, the success in these urban, Level I centers may not be immediately transferable to hospitals with less experience in penetrating injury or with more limited resources. There are several other reasons why this type of approach may not be immediately applicable to all institutions. This type of approach is applied to only a small percentage of patients, and the vast majority of patients with penetrating injury will need immediate operative exploration. Thus, if a center cares for only 10 to 20 penetrating patients annually, only 1 or 2 patients a year may qualify for this type of treatment. A small
Figure 5.
Wounds caused by a highly destructive weapon, in this case a shotgun. Notice the large wounds with extensive tissue damage. Patients with gunshot injury from highly destructive weapons, such as a rifle, military weapon, or shotgun, are often excluded from nonoperative treatment strategies.
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census of gunshot injuries may not allow the practitioners to develop the mature judgment that comes from extensive experience in treating patients with penetrating injury. In addition, nonoperative approaches require continuous evaluation by an experienced surgeon and necessitate a system that can provide ongoing monitoring and scrutiny. Thus, further studies, including involvement of Level II and III trauma centers, will be needed to determine the universality of this type of management for gunshot injury. Author contributions: PMR conceived of the study. JPP drafted the manuscript. GPD and MDG provided literature review; GPD provided figures. CWS contributed to editing of the manuscript and provided information on wounding patterns and imaging. PMR, GPD, and MDG contributed to the final revision. JPP takes responsibility for the paper as a whole. Received for publication November 22, 2002. Revisions received June 10, 2003, and July 7, 2003. Accepted for publication August 7, 2003. The authors report this study did not receive any outside funding or support. Reprints not available from the authors. Address for correspondence: John P. Pryor, MD, Division of Traumatology and Surgical Critical Care, 3440 Market Street, Philadelphia, PA 19104; 215-662-7323, fax 215-614-0375; E-mail [email protected]. edu.
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