No anatomical region or cavity is exempt when addressing injuries sustained when managing multi-trauma patients, especially if the traumatic injury is the result of a blunt mechanism. This cornerstone principle is the paramount rationale for the two-tier, systematic approach for the injured patient. In most settings, the acute care surgeon (a specialist who has expertise in trauma, critical care, and emergency general surgical management) is heavily involved in every aspect of care of the trauma patient. Abdominal trauma, regardless of the mechanism of injury, can present many challenging situations, even for the most well trained and talented surgeon. With the pendulum continuing to move more toward nonoperative/selective management of abdominal trauma due to enhanced diagnostic modalities, the hazards of missed or delayed diagnoses are well known and equally well respected. The unevaluable abdomen in a patient who has an associated closed head injury or substantial intoxication with a depressed sensorium remains a perplexing dilemma, irrespective of an unprecedented myriad of advanced technology designed to detect the sequence of intra-abdominal injury.

In addition, there are special populations (the elderly, immunosuppressed, anticoagulated, morbidly obese, etc.) that pose unique management challenges. While the explosion of laparoscopic intervention has made an indelible imprint on practically every surgical discipline, its impact on trauma management has been mostly diagnostic in the hemodynamically normal patients, as opposed to therapeutic management of the injured patient. With the hemodynamically compromised patient being the prototypical individual who is taken to the operating room for exploration, a laparoscopic approach would be an absolute contraindication in that cohort of patients.

Traumatic injury remains the leading cause of death both in the United States and worldwide, resulting in enormous economic and societal losses. In many regions of the world, there is a significant shortage of surgical specialists and general surgeons. This is particularly problematic given the fact that it is the general surgeon specialist who still provides the bulk of emergency surgical care. Given the fact that there are many regions of the country and the world without established trauma systems, this chapter is as applicable to the general surgeon as it is to the trauma surgeon.

Initial Management

Even though the abdomen remains one of the most critical and vulnerable anatomic regions in blunt trauma, a standard, systematic approach of the entire patient must always be conducted—without exception. An initial assessment of the entire patient is imperative before focusing on the specific anatomical region where there is an obvious traumatic injury. The concept of initial assessment includes the following components: (1) rapid primary survey, (2) resuscitation, (3) detailed secondary survey (evaluation), and (4) reevaluation. Such an assessment is the cornerstone of the Advanced Trauma Life Support (ATLS^®) program.¹ Integrated into primary and secondary surveys are specific adjuncts. Such adjuncts include the application of electrocardiographic monitoring and the utilization of other monitoring modalities such as arterial blood gas determination, pulse oximetry, the measurement of ventilatory rate and blood pressure, insertion of urinary and/or gastric catheters, and incorporating necessary x-rays and other diagnostic studies when applicable, such as focused abdominal sonography for trauma (FAST) exam, other diagnostic studies (plain radiography of the spine/chest/pelvis and computed tomography [CT]). The initial assessment essentially underscores the prioritization of patient management. Determination of the status of an airway and optimal oxygenation (airway [A] and breathing [B]) are inevitably the top priorities followed by assessing the adequacy of blood flow—circulation (C). For example, when an airway is believed to be inadequate, the establishment of a rapid-sequence translaryngeal endotracheal intubation might be indicated, or if circulation is deemed suboptimal and bleeding is suspected, an expeditious search for external or cavitary (peritoneum, thorax) source is conducted. Following the “ABCs” of the primary survey is a rapid assessment of the neurological status for gross disability (D)—including determining (1) the level of consciousness, (2) motor function (extremity movement), (3) sensory function, and (4) the presence of reflexes (pupillary, bulbocavernosus). This rapid neurologic assessment allows for the calculation of a Glasgow Coma Score (GCS). The last component of the primary survey is ensuring that full exposure (E) of the patient is achieved, along with environmental control, in order to lessen the chance of the patient becoming hypothermic.

The focus of the primary survey is to both identify and expeditiously address immediate life-threatening injuries. In addition to resuscitation, the necessary adjuncts to the primary survey (and secondary evaluation) include electrocardiographic monitoring, placement of urinary and gastric catheters (when appropriate and not contraindicated), along with the close monitoring of physiologic parameters such as respiratory rate, pulse rate, blood pressure, pulse pressure, arterial blood gases, body temperature, and urinary output. Only after the primary survey is completed (including the initiation of resuscitation) and hemodynamic stability is addressed should the secondary survey be conducted, which entails a head-to-toe (and back-to-front) physical examination, along with a more detailed history. Normalization of all vital functions should be evident before proceeding to the secondary survey.

PRIMARY SURVEY

Only the emergency care disciplines of surgery/medicine have a two-tier approach to their initial assessment of the patient, with primary and secondary surveys being integral components. As highlighted above, the primary survey is designed to quickly detect life-threatening injuries. Therefore, a universal approach has been established with the following prioritization:

• 
  

  Airway maintenance (with protection of the cervical spine)

  
  
• 
  

  Breathing (ventilation)

  
  
• 
  

  Circulation (including hemorrhage control)

  
  
• 
  

  Disability (neurologic status)

  
  
• 
  

  Exposure/environmental control

Such a systematic and methodical approach (known as the ABCDEs of the initial assessment) greatly assists the surgical/medical team in the timely management of those injuries that could result in a poor outcome.

1. 
   

   Airway assessment management (along with cervical spine protection): Because loss of a secure airway could be lethal within 4 minutes, airway assessment/management always has the highest priority during the primary survey of the initial assessment of any injured patient, irrespective of the mechanism of injury or the anatomical wound. The chin lift and jaw thrust maneuvers are occasionally helpful in attempting to secure a patient airway. However, in the trauma setting, the airway management of choice is often translaryngeal, endotracheal intubation. If this cannot be achieved due to an upper airway obstruction or some technical difficulty, a surgical airway (needle or surgical cricothyroidotomy) should be the alternative approach. No other management can take precedence over obtaining an appropriate airway control. Until adequate and sustained oxygenation can be documented, administration of 100% oxygen is required.

   
   
2. 
   

   Breathing (ventilation assessment): An airway can be adequately established and optimal ventilation still not be achieved—for example, when there is an associated tension pneumothorax. Other examples include a substantial hemothorax, open pneumothorax, or a large flail chest wall segment. Worsening oxygenation and an adverse outcome would ensue unless such problems are expeditiously addressed. Therefore, assessment of breathing is imperative, even when there is an established and secure airway. A patent airway but poor gas exchange will still result in a poor outcome. Tachypnea, absent breath sounds, percussion hyperresonance, distended neck veins, and/or tracheal deviation are all consistent with inadequate gas exchange. Decompression of the pleural space with a needle/chest tube insertion should be the initial intervention for a pneumo/hemothorax that compromises a patient’s respiratory and/or cardiovascular status. A large flail chest, with underlying pulmonary contusion, will likely require endotracheal intubation and administration of positive pressure ventilation.

   
   
3. 
   

   Circulation assessment (adequacy of perfusion management): The most important initial step in determining adequacy of circulatory perfusion is to quickly identify and control any active source of bleeding, along with restoration of the patient’s blood volume with crystalloid fluid resuscitation and blood products, if required. Decreased levels of consciousness, pale skin color, slow (or nonexistent) capillary refill, cool body temperature, tachycardia, or diminished urinary output are all suggestive of inadequate tissue perfusion. Optimal resuscitation requires the insertion of two large-bore intravenous lines and infusion of crystalloid fluids (warmed). Adult patients who are severely compromised will require a fluid bolus (2 liters of Ringer lactate or saline solution). Children should receive a 20 mL/kg fluid bolus. Blood and blood products are administered as required. Along with the initiation of fluid resuscitation, emphasis needs to remain on identifying the source of active bleeding and stopping the hemorrhage. For a patient in hemorrhagic shock, the source of blood loss will be an open wound with profuse bleeding, or within the thoracic or abdominal cavity, or from an associated pelvic fracture with venous and/or arterial injuries. Disposition (operating room, angiography suite, etc.) of the patient depends on the site of bleeding. For example, a FAST assessment that documents substantial blood loss in the abdominal cavity in a patient who is hemodynamically labile dictates an emergency celiotomy. However, if the quick diagnostic workup of a hemodynamically unstable patient who has sustained blunt trauma demonstrates no blood loss from an open wound in the abdomen or chest, then the source of hemorrhage would likely be from a pelvic injury, necessitating angiography/embolization of a probable arterial injury, if external stabilization (eg, a commercial wrap or binder) of the pelvic fracture fails to stop the bleeding. Profuse bleeding from open wounds can usually be addressed by application of direct pressure or occasionally ligating torn arterial vessels that can easily be identified and isolated.

   
   
4. 
   

   Disability assessment/management: Only a baseline neurologic examination is required when performing the primary survey in order to determine neurologic function deterioration that might necessitate surgical intervention. It is inappropriate to attempt a detailed neurologic examination initially. Such a comprehensive examination should be done during the secondary survey or evaluation. This baseline neurologic assessment could be the determination of the GCS, with an emphasis on the best motor or verbal response, and eye opening. An alternative approach for a rapid neurologic evaluation would be the assessment of the pupillary size and reaction, along with establishing the patient’s level of consciousness (alert, responds to visual stimuli, responds only to painful stimuli, or unresponsive to all stimuli). The caveat that must be highlighted is the fact that neurologic deterioration can occur rapidly, and that a patient with a devastating injury can have a lucid interval (eg, epidural hematoma). Because the leading causes of secondary brain injury are hypoxia and hypotension, adequate cerebral oxygenation and perfusion are essential in the management of a patient with neurologic injury.

   
   
5. 
   

   Exposure/environmental control: In order to perform a thorough examination of a patient, he/she must be completely undressed. This often requires cutting off the garments to safely expedite such exposure. However, care must be taken to maintain normothermia and prevent the patient from becoming hypothermic. Adjusting the room temperature and infusing warmed intravenous fluids can help establish an optimal environment for the patient.

SECONDARY SURVEY

As noted earlier, the secondary survey should not be done until the primary survey has been completed and resuscitation initiated, with some evidence of normalization of vital signs. It is imperative that this head-to-toe (front and back) evaluation be performed in a detailed and systematic fashion in order to detect less obvious or occult injuries. This is particularly important in the unevaluable (eg, head injury or severely intoxicated) patient. The management of blunt abdominal trauma continues to evolve more in the nonoperative arena, as opposed to surgical intervention. The workup has shifted largely from the use of physical exam, plain x-ray, laboratory findings, and diagnostic peritoneal lavage (DPL) to the extensive use of CT and ultrasonography. Treatment for visceral injury has traditionally been surgical, but many forms of solid organ injury can now be successfully managed nonoperatively or with minimally invasive and interventional radiology techniques. Management of the multiple injured trauma patient at Level I trauma centers, with state-of-the-art techniques, has now conclusively shown significantly improved patient outcomes and survival.²

Diagnostic and Imaging Techniques

DIAGNOSTIC PERITONEAL LAVAGE

DPL has now been essentially supplanted by the adoption and now popularity of abdominal sonography. The utilization of DPL has diminished substantially. Originally described by Root in 1965, DPL was once a mainstay in the management of blunt abdominal trauma for over four decades.³ Before the era of routine CT scanning, it was used as a screening tool to evaluate patients having blunt or penetrating abdominal trauma with an accuracy rate reported between 92% and 98%.^4–9 CT scans and FAST are now the diagnostic modalities of choice in assessment of the injured patient. However, DPL remains an excellent tool for further workup of occult bowel injury or in unstable patients when FAST is not available or has questionable findings. In the workup for occult bowel injury, traditional parameters (Table 19-1) should be used to guide therapy. In unstable patients and when FAST is not an option, a diagnostic tap is usually all that is necessary, and exploration is indicated when there is aspiration of greater than 10 mL of gross blood.

The pitfalls of DPL are a relatively high false positive rate, risk of creating visceral injury, and poor sensitivity for detecting injury to retroperitoneal structures such as the pancreas and duodenum.^10–12 Iatrogenic events are minimized if a Foley catheter and nasogastric tube are placed prior to the procedure. Patients with pelvic fractures and suspected retroperitoneal hematoma or pregnant females should undergo a supra-umbilical approach. Visceral injury is less likely with an open approach but more time-consuming and invasive.^13–16 Checking amylase or lipase in the lavage sample, concomitant use of CT scan, and high index of suspicion are necessary to avoid missed retroperitoneal injury.

FOCUSED ABDOMINAL SONOGRAPHY FOR TRAUMA

In the diagnostic assessment of the acutely injured patient, the bedside ultrasonography for detection of cardiac and intra-abdominal injury is considered the standard of care. Because focused abdominal sonography for trauma is of a noninvasive nature, this diagnostic modality allows the operator to perform an exam simultaneously during the initial resuscitation and stabilization of a multiple injured trauma patient. Due to the relative insensitivity of abdominal examination in the severely injured patient, this technique may provide evidence of significant hemorrhage early in the course of an evaluation. An ultrasound probe is used to examine four key windows for fluid; the subxiphoid area permits visualization of the pericardium, the left subcostal area visualization of the splenorenal recess, right subcostal area visualization of Morison pouch, and the suprapubic area visualization of the pelvic cul de sac (Fig. 19-1). The presence of fluid may indicate presence of cardiac tamponade (fluid in the pericardial space), intra-abdominal hemorrhage, hollow viscus perforation, hemoperitoneum, or ascites. False positive results secondary to preexisting ascites or false negatives due to operator error and/or body habitus are the main limitations. Scanning the suprapubic area with distension of the urinary bladder will enhance the sensitivity of the exam for the detection of pelvic fluid.

A threshold of at least 200 mL of fluid in the abdominal cavity is necessary for detection, and intra-abdominal injuries must be associated with the presence of this much free fluid for a positive finding.¹⁷ Reported sensitivities range between 73% and 88% and specificity between 98% and 100%.¹⁸ Accuracy rates range from 96% to 98%. FAST is an inexpensive, rapid, portable, noninvasive technique that can be performed in serial fashion if there is a change in patient stability.^19–21 In addition, it obviates the risk of exposing pregnant females to radiation. Positive findings in stable patients can be further evaluated with CT, while unstable patients with a positive finding should prompt the surgeon to take the patient to the operating room for emergent exploration. Workup of a patient with a reliable abdominal exam may be complete with a negative FAST in the absence of abdominal signs or symptoms.

COMPUTED TOMOGRAPHY

Steady advances in the technology and speed of CT have continued to be an intergral part of the diagnostic management of trauma patients. Multidetector scanners have drastically improved resolution and accuracy of these imaging studies. Negative predictive values as high as 99.63% have been reported for patients sustaining significant mechanisms of blunt trauma allowing the use of CT as a reliable and noninvasive screening tool for screening patients with blunt abdominal trauma.²² In light of modern-day CT capabilities, prospective data have demonstrated that patients with a signinficant mechanism and a benign abdomen can be released from the emergency department if a CT scan of the abdomen shows no evidence of visceral injury provided that there are no other reasons for hospitalization.²²

CT reliably identifies injuries in solid organs such as the spleen, liver, and kidney because of the associated vascular nature demonstrating disruption of normal architecture, associated free fluid, and the so-called vascular blush.²³ Established grading scales continue to be used for accurate classification and determination of management plan (Tables 19-2 19-3, 19-4).^23,24

Detection of bowel injury via CT scan in patients who are intoxicated, intubated, or who have associated closed head injury or other distracting injuries, can present a diagnostic challenge in the absence of a reliable abdominal exam. The incidence of blunt bowel injury varies from series to series but is generally reported in the 1% to 5 % range in all blunt trauma patients admitted to Level I trauma centers.^25,26 A high index of suspicion is predicated on mechanism of injury and physical exam findings, such as abdominal wall ecchymosis, tattooing, and/or seatbelt sign. CT findings may be overt such as extravasation of oral contrast or pneumoperitoneum, or more commonly subtle findings such as bowel wall thickening, stranding of the mesentery, or free fluid in the absence of solid organ injury. Indirect findings may be fairly nonspecific and secondary to bowel edema from resuscitation or preexisting ascites. Reproductive age females may have a small amount of normal or “physiologic” pelvic fluid present, sometimes adding to the complexity of the evaluation. Patients on positive pressure ventilation or with significant barotrauma may develop mediastinal or subcutaneous emphysema that can track through the peritoneum or retroperitoneum and give the appearance of free air. Great care in the radiologic interpretation and close clinical correlation are necessary in such cases. The liberal use of diagnostic modalities (eg, abdominal CT scan) in the hemodynamically normal injured patient may prevent nontherapeutic laparotomies. Obviously, when significant doubt remains, abdominal exploration may be required to confirm an injury.

The role of oral contrast in evaluation of the acutely injured patient has recently come under question. Little time is usually available in the emergency setting to permit adequate opacification of the small bowel. Patients are further at risk for aspiration of the contrast media, and administration often requires placement of a nasogastric tube. There have been several reports that have shown that elimination of oral contrast media does not lead to an increased incidence of missed bowel injury.^25–27 Many centers have now safely eliminated the use of oral contrast media from their routine trauma protocols, expediting management and ease of patient care. Resuscitation edema may cause a hazy appearance around the head of the pancreas and duodenal c-loop, raising the question of a pancreas or duodenal injury. Further clarification in this situation can be obtained when it occasionally occurs via repeat CT scan with the administration of oral contrast and the injection of a 300- to 500-cc bolus of air down the nasogastric tube in order to make pneumoperitoneum obvious.

CT may also be of great importance in identifying patients with arterial hemorrhage related to pelvic fracture. CT imaging may demonstrate an arterial blush or large hematoma in the vicinity of a pelvic fracture indicating the need for pelvic arteriography or pelvic external fixation. A “CT cystogram” may also be helpful and eliminate redundancy of radiographic evaluation. The Foley catheter is clamped after placement in the trauma bay. Real-time interpretation of the CT scan is performed by the evaluating physician, which may dictate further delayed images or a formal three-view (anterior/posterior, lateral, and postvoid views) cystogram.

The Bowel

There is yet no place for nonoperative management of hollow viscus injury, and the nemesis of nonoperative management of blunt abdominal trauma is therefore the missed bowel injury and all its catastrophic consequences. Otherwise, most management is straightforward: debridement and primary repair for nondestructive injuries and resection with primary repair versus stomal formation for destructive injuries.

RADIOGRAPHIC FINDINGS OF BLUNT BOWEL INJURY

There are two basic types of findings of bowel injury on CT scan: direct and indirect. Direct findings are usually straightforward if present and amount to extravasation of oral contrast (if administered) and free air, which have been reported to occur in 4% and 28% of the time, respectively. Little else can explain the first of these two entities, while free air from other sources such as extensive subcutaneous emphysema tracking through a diaphragmatic hiatus is unusual.^28–30 Such findings may be subtle and can vary in presentation depending on the quality of the scan. Indirect findings include mesenteric hematoma or contrast blush, bowel wall edema, unexplained free fluid, “fat streaking,” and bowel loops that do not opacify with intravenous contrast (Table 19-5).

Mesenteric hematoma is nonspecific and can occur from associated injuries, such as pelvic fractures or renal injuries, with hematomas from these structures expanding into the bowel mesentery. However, a vascular blush in the leaves of the mesentery is indicative of active hemorrhage until proven otherwise, and generally is a determinant for immediate operative exploration. Bowel wall edema and ascites are common in blunt trauma patients, can occur from resuscitation of other injuries, and do not necessarily connote bowel injury. Free fluid in the absence of solid organ injury can be further evaluated with DPL if the abdominal exam is unreliable. Fat streaking can occur with mesenteric contusion and does not necessarily portend an operative indication. Unopacified bowel loops can indicate vascular disruption of the mesentery or simply be due to poor contrast timing in an under-resuscitated patient. Evidence of these findings increases the likelihood of finding an injury at exploration when there is an increasing number of these findings.

OPERATIVE MANAGEMENT

Appreciation of the American Association for the Surgery of Trauma (AAST) organ injury grading scale is helpful in describing wounds of the bowel.³¹ Grade I injuries are contusions and partial thickness lacerations of the bowel wall without perforation. Grade II injuries are full thickness wounds involving less than 50% of the bowel wall circumference. Grade III are lacerations comprising greater than 50% of the bowel wall circumference without complete transection. Grades IV and V injuries represent complete transection of the bowel wall and transection with segmental tissue loss and/or devascularization of the mesentery, respectively. The terms destructive and nondestructive simplify the terminology; nondestructive wounds are those injuries that can be managed with debridement and primary-suture enterorrhaphy and are comprised of grades I through III.³² Destructive wounds require resection of an entire segment of the bowel due to loss of colonic integrity or devascularization of the mesentery and encompass grades IV and V (Tables 19-6 and 19-7).

The distinction between destructive and nondestructive wounds is important in terms of the prescribed management. Nondestructive wounds of the large or small bowel can generally be repaired without further consideration. Most small bowel destructive injuries should be resected and reconstituted unless damage control conditions prevail. In contrast to the small bowel, the management of colon injuries has received great scrutiny. Ushering in the dawn of modern-day trauma surgery, the World War II military experience dictated that all colon wounds, destructive or not, be managed by colostomy. This philosophy remained surgical dogma until the 1980s.^33,34 In a comprehensive review of the literature since 1979, primary repair of the colon for nondestructive wounds was shown to have a leak rate of 1.6%.³² Compared to patients receiving colostomy for similar types of wounds, the incidence of intra-abdominal abscess was 4.9% for primary repair and 12% for colostomy, and overall complication rate was 14% for primary repair and 30% for colostomy. Mortality rates were similar at 0.11% for primary repair and 0.14% for colostomy. These findings clearly show the superiority of primary repair for nondestructive wounds of the colon.

Several risk factors for anastomotic failure pertaining to destructive colon injury have been addressed in the literature: hypotension, shock, interval from injury to operation, amount of fecal contamination, associated organ injury, transfusion requirement, and comorbid disease.³⁵ No data have conclusively shown that any of these risk factors increase the likelihood of anastomotic failure. Patients with massive blood loss or shock may be better served by undergoing a damage control procedure, with delay of definitive repair.³⁶ Interval from injury to repair greater than 12 hours can be a relative contraindication to definitive repair if there is widespread (greater than one quadrant) fecal contamination. Greater than one or two organ system injury has been a concern, but this may just be a marker for degree of shock and overall physiologic derangement. Comorbidities, such as AIDS and cirrhosis, deserve special consideration and these patients may be better off with the establishment of an ostomy diversion.^37,38 Patients with any of these risk factors have a higher incidence of intra-abdominal abscess and overall complication rates.³²

Notwithstanding the caveats of these comorbidities, colonic resection and primary anastomosis for destructive wounds would be permissible in most trauma settings. In a collective review of 207 patients reported in the literature, management of destructive bowel injury with resection and primary anastomosis had a reported leak rate of 7.2%, with a mortality of 1.7% attributable to the colon wound.³² In the largest single-institution experience, Murray showed a leak rate of 11% in 112 patients undergoing resection and primary anastomosis for destructive colon wounds, with two deaths related to leaks.³⁹

In a multi-institutional trial, Demetriades reported 297 patients with destructive colon wounds in which 197 underwent resection and anastomosis and 100 underwent diversion.³⁷ The choice of operation was left to the discretion of the attending surgeon at the time of exploration. Not surprisingly, the patients with diversion were significantly more injured and critically ill than those undergoing reestablishment of intestinal continuity. The anastomotic leak rate was 6.6%, with one leak from the stump of a Hartmann pouch in the diverted group and four deaths related to anastomotic failure. Multivariate analysis showed no significant difference in mortality or abdominal complications between diversion and primary anastomosis groups. The authors concluded that “patients can be managed by primary repair regardless of risk factors.” This study certainly demonstrates a liberal use of resection and primary anastomosis in relatively sick and injured cohort of patients. However, the ultimate decision for the choice of operation was up to the discretion of the surgeon at the time of operation on a case-by-case basis—for which there is no substitute.

At laparotomy, the bowel should be examined in its entirety after all other sources of major bleeding are controlled. Small injuries should be noted and tagged with an identifiable suture for easy reference. Larger wounds contributing to ongoing soiling can be temporarily controlled with a whipstitch (quick running suture) or Babcock clamps. Mesenteric injuries are identified and active bleeding controlled appropriately. Attention should be directed to the location of the superior mesenteric artery for injuries encroaching on the root of the mesentery. Mesenteric hematomas should be explored with ligation of injured vessels and mesenteric defects closed by careful reapproximation of the peritoneal edges so as not to compromise any associated vasculature. Bowel viability should be noted in relation to any mesenteric injury. Clusters of grade I through III injuries may be resected or individually repaired depending on the particular injury pattern. In blunt trauma, there are usually only one or two grade II or III wounds that can be repaired primarily or one or more devitalized segments that require resection.

Small, superficial grade I injuries can be left alone, while deeper, longer grade I injuries can be closed with a simple running suture or interrupted Lembert sutures. Grade II and III wounds should be debrided back to healthy, viable bowel and closed transversely, preventing narrowing of the lumen of the bowel. Single-layer running or interrupted closure is generally sufficient for repair of small bowel. When there is significant bowel wall edema, peritonitis, or soiling, a two-layer closure with a running inner layer and interrupted Lembert outer layer may be preferential. Grade I and II colon wounds may be managed with single-layer closure. However, grade III colon wounds should be closed in two layers for added protection.

The leak rate associated with stapled versus hand-sewn anastomosis for destructive wounds of the bowel has been an area of ongoing controversy. In a two retrospective studies totaling 284 patients undergoing stapled versus hand-sewn anastomosis, Brundage showed that hand-sewn procedures had lower leak rates.^40,41 Two other retrospective studies totaling 484 patients showed no difference in the leak rate of stapled versus hand-sewn procedures.^42,43 Brundage’s two studies included 78 colon wounds, while the other studies were confined only to the small bowel. Stapled procedures may be a little quicker, particularly if there is more than one anastomosis. In general, the technique chosen according to the literature can be a matter of surgeon’s preference. However, with edematous bowel, the hand-sewn technique is a more prudent approach.

The Spleen

The spleen is the most commonly injured intra-abdominal organ, followed by the liver and small bowel in blunt trauma patients. The spleen’s location in the left upper quadrant lends susceptibility to injury from broken ribs, deceleration, and blunt percussion forces. Clinically, patients with splenic injury may present with hypotension, left upper quadrant pain or tenderness to palpation, or diffuse peritonitis from extravasated blood. Referred pain to the left shoulder on deep inspiration in the face of splenic hematoma is known as Kehr sign.

NONOPERATIVE MANAGEMENT

Most series indicate that approximately 60% to 80% of patients presenting with blunt splenic injury can be managed nonoperatively at Level I or II trauma centers.^44–48 Facilities without the resources and experienced of a bona fide trauma team may not safely meet the demands of nonoperative management and should consider patient transfer.⁴⁹ Patients selected for nonoperative management must have normal vital signs, be free of peritoneal signs or other concern for hollow viscus injury, and have no evidence of free extravasation of intravenous contrast from the splenic parenchyma (Fig. 19-2).

Considerable debate remains regarding risk factors for failure of nonoperative management. Higher AAST splenic injury grade, age greater than 55 years, moderate to large hemoperitoneum, subcapsular hematoma, and portal hypertension have all been suggested to increase the risk of failure. Early reports in the evolution of nonoperative management regarding AAST grade did not demonstrate higher failure rates for higher-grade injury. More recent reports using high-resolution multidetector CT scanners allow better assessment of injury grade. The data from these studies show patients with injury grades III to V to be at increased risk for nonoperative failure.^44,46 Age continues to be controversial subject in the literature, with numerous reports claiming that age greater than 55 years either is or is not a risk factor for failure.^44,46,50 Documentation of a moderate or large hemoperitoneum is suggestive of a major injury and should be considered a significant factor in individual patient assessment.

Patients with splenic subcapsular hematoma or history of portal hypertension are specific subgroups of patients that deserve special consideration. This cohort of patients with subcapsular hematoma in our experience tend to ooze from the raw parenchymal surface and further disrupt the capsule, leading to more raw surface area to bleed. These patients are at increased risk for delayed rupture 6 to 8 days following injury and may already be discharged from the hospital if they have isolated injury. Furthermore, splenic embolization is not a very effective treatment for this condition because it usually necessitates coiling of the main splenic artery, which can lead to significant pain and abscess formation. History of portal hypertension or cirrhosis, while not an absolute contraindication to nonoperative management, certainly should serve as a caveat. The general risks of laparotomy in a Child–Pugh B or C cirrhotic patient need to be carefully weighed against the risk of ensuing and worsening coagulopathy. This scenario may indeed dictate the need for splenic artery embolization. None of these risk factors alone should dictate the decision to proceed immediately to operative intervention. Nonoperative management does reduce hospital length of stay and transfusion requirement; however, the morbidity of splenectomy should remain low in any surgeon’s hands. Overall, the patient’s condition, including comorbidities, coagulopathy, and other problems (such as traumatic brain injury, aortic injury, and suspicion for concomitant hollow viscus injury) factor into the decision-making process. No one should ever succumb to splenic hemorrhage that was undergoing nonoperative management.

Approximately 20% of patients initially undergoing nonoperative management of blunt splenic injury require further intervention. Failure has been associated with the presence of a contrast blush in up to two-thirds of these patients.⁵¹ The presence of a contained contrast blush within the parenchyma of the spleen represents pseudoaneurysm formation of a branch of the splenic artery. Angioembolization is now commonly used to selectively occlude the arterial branches containing these injuries.^{44,45,48,52,53} Implementation of this salvage technique at centers that routinely screen for the presence of pseudoaneurysm has increased the success of nonoperative management to 90% or greater. Pseudoaneurysm formation has been observed in even grade I and II injuries, and may not be present on the initial imaging.^44,47,53 Therefore, follow-up CT scan is recommended on all patients with splenic trauma within 24 to 48 hours after injury. If these images show stable injuries without pseudoaneurysm formation, expectant management can continue.

Long-term data are unavailable concerning the risk of outpatient or delayed rupture, but the incidence is low and has been reported to be about 1.4%.⁵⁴ The average date to readmission for delayed splenectomy after discharge was 8 days in this study. Lower grade (I, II) injuries tend to heal more quickly, and most injuries are healed by 5 to 6 weeks.⁵⁵ However, approximately 20% of blunt splenic injuries will not show complete healing and may be at risk for pseudocyst formation. A CT scan should be repeated in 6 weeks for grade I and II injuries and 10 to 12 weeks in grades III to V before allowing the patient to return to normal activity.

SPLENECTOMY

Patients requiring urgent or emergent intervention for splenic hemorrhage may develop hypothermia, coagulopathy, and visceral edema. The most expeditious and safest course of action under these conditions is removal of the spleen. The general assumption of abdominal exploration for trauma is that there are known, and possibly unknown, injuries. The operative approach is via a midline vertical incision that allows the best exposure and facilitates temporary abdominal closure should visceral edema or damage control measures be necessary.