Although the nonsurgeon intensivist does not need detailed knowledge of the surgical management of specific intraabdominal injuries, some familiarity with the diagnostic and management principles to be applied in the surgical treatment of specific intraabdominal organ injuries is likely to improve the confidence with which these patients are managed in the ICU.
Penetrating abdominal injury differs significantly from nonpenetrating injury. Penetrating injury may result from stab wounds or wounds from other sharp objects or from bullet or shotgun wounds. Stab wounds tend to be the least serious, in that they involve organs only within the short trajectory of the weapon, and unless the stab wound impales a major vessel directly, major hemorrhage is not as likely as in other forms of penetrating or blunt abdominal injury. Patients with stab wounds require exploration of the wound to determine whether the peritoneum has been violated. If the peritoneum has been violated, a decision has to be made to proceed with formal laparotomy unless one is prepared to use peritoneal lavage as an adjunctive test in determining whether laparotomy should be conducted.42 Although a selective approach using imaging such as CT and MRI to identify tangential nonpenetrating wounds that would not require laparotomy is suggested, generally, all bullet and shotgun wounds to the abdomen require laparotomy.44 These missile injuries usually result in damage to more than one organ. Since kinetic energy transfer is affected most significantly by missile velocity (K = 1 ½ MV2), low-velocity missiles tend to produce limited surrounding injury, whereas high-velocity missiles produce greater damage. Organ involvement, therefore, is very unpredictable because of the variable trajectory and wide variable area of dissipated energy. A straight line joining the points of entry and exit usually does not represent the pathway of the missile. In shotgun injuries, much less damage is inflicted when the injury occurs from far range rather than close range.
The crushing force produced by blunt injuries results in very irregular lacerations. Multiple injuries are also common. Diagnosis and therapy are more challenging and should be more aggressive with blunt injury. Hemorrhage, devitalization of tissue, morbidity, and mortality are all increased in blunt injury compared with penetrating injuries of the abdomen.
The frequency of organ involvement in penetrating trauma is also different from that in blunt trauma to the abdomen. In penetrating trauma, the organs involved, in order of frequency, are the liver, small bowel, stomach, colon, major vessels, and retroperitoneum. In blunt injuries, the solid organs—the spleen, kidney, and liver—are damaged most often, followed by the intestines.54
The diagnosis of stomach injury is suggested by epigastric pain and pain at the shoulder tip if there is free perforation. Usually there is very minimal hemorrhage, and the patient's hemodynamic status is not particularly affected. Upright chest x-ray reveals free air under the diaphragm. The diagnosis also may be suggested by bloody aspirate from the nasogastric tube.
The surgical treatment of stomach injuries is straightforward and involves débridement of devitalized tissue and usually primary suture or anastomosis if resection is required for wide areas of devitalization. It is essential that the entire stomach, including the posterior wall, is visualized to minimized missed injuries.
These injuries are seen often in association with other injuries, and the second portion of the duodenum is involved most commonly. Because the duodenum is a retroperitoneal structure, frank peritonitis is a very late sign, and the diagnosis is made only with a very high index of suspicion based on the mechanism of injury. A useful sign is the identification of retroperitoneal air on a plain film of the abdomen (Fig. 95-7). Occasionally, a free perforation of the first portion of the duodenum produces pneumoperitoneum and can be identified on an upright chest film.
Ruptured duodenum. A. Plain radiograph showing retroperitoneal air around the right kidney. B. Transected duodenum found at laparotomy on the same patient.
In the surgical treatment of injuries to the duodenum, complete mobilization and visualization of the entire duodenum are crucial. Patients with intramural hematomas of the duodenum may present with vomiting and symptoms of gastric outlet obstruction; radiologic examination of the stomach and duodenum with contrast agents reveals the presence of an intramural hematoma. If this is the only injury, treatment can be conservative, with nasogastric suctioning and intravenous fluids until the hematoma resolves. If the lesion is found at laparotomy, the hematoma is evacuated easily through an incision in the duodenal wall.55 The principle of treatment is to débride the area of injury, removing all devitalized tissue. If, after this is accomplished, the edges of the duodenum can be approximated without undue tension, primary suture closure is appropriate. The defect also may be closed by a serosal patch from adjacent small bowel or a resection and end-to-end anastomosis. When these techniques are not possible, then roux-en-Y anastomosis between the duodenal ends and the small bowel needs to be conducted. When there is concern about the duodenal closure, it is wise to place a duodenal catheter, brought out as a tube duodenostomy. If the anastomosis is not secure, the resulting duodenal fistula will be controlled and can be treated by observation and parenteral nutrition until the fistula tract matures, after which the duodenal tube is removed.56,57 Severe duodenal injuries require pyloric exclusion procedures in which the gastric contents are diverted through a gastrojejunostomy.58
Injuries to the pancreas usually result from blunt trauma and are caused by impact of the pancreas against the vertebral column. Diagnosis is often difficult because the retroperitoneal position of this organ prevents early physical signs of peritoneal irritation. Frequently, the diagnosis is made at laparotomy for other associated conditions. However, the diagnosis is suggested by an increase in the serum amylase level. If the diagnosis is suspected and findings on physical examination are minimal, upper gastrointestinal radiographic studies with gastrograffin may demonstrate a widening of the duodenal loop. CT of the abdomen allows assessment of the retroperitoneum and pancreatic area for evidence of retroperitoneal hematomas or even ductal injury. Peritoneal lavage frequently is negative in the presence of severe retroperitoneal pancreatic injuries.
Treatment of these injuries depends largely on whether or not the pancreatic duct has been violated. In simple contusions of the pancreas, drainage of the area is all that is required after mobilization of the pancreas and full inspection to rule out any associated ductal injury. Any devitalized area should be débrided, and bleeding points should be controlled by direct suture ligations combined with cautery.
Ductal injury usually is identified during laparotomy. However, in exceptional circumstances where endoscopic retrograde pancreatography (ERP) is immediately available in an otherwise stable patient, this may allow assessment of ductal integrity prior to the laparotomy.59 When the duct has been injured, there is often a mixture of pancreatic fluid and blood over the surface of the pancreas, which should be exposed for complete inspection. Although ductal injury involving the body and tail of the pancreas may be treated by transection and anastomosis of the ends of the duct to the small bowel, this injury is treated more appropriately by distal pancreatic resection without an enteroanastomosis. When the head of the pancreas is involved, a roux-en-Y anastomosis of the distal pancreatic segment is advisable.60 This type of injury usually is a combined pancreaticoduodenal injury and may require a Whipple procedure (pancreaticoduodenectomy). This procedure carries a high mortality and should be conducted only when more conservative measures are unsuccessful.61,62 An alternative approach to combined pancreaticoduodenal injury is the diverticulization procedure, in which the pylorus is closed internally, and a gastrojejunostomy is constructed with an added option of drainage of the duodenum through a tube duodenostomy after repair of the duodenal injury and wide drainage of the pancreas. The entire area is drained, with drains placed around the peripancreatic and duodenal area and exiting posteriorly.63 It should be emphasized that pancreaticoduodenal resection should be a last resort because of the high associated mortality. Less aggressive treatment should be instituted initially if possible.39 Even though this approach is more likely to result in complications such as pancreatic abscess, the overall mortality is still less with drainage than with resection.
Postoperatively, patients with pancreatic injury are at risk for development of complications such as pancreatic abscess and pseudocyst. The former is suggested by a continued septic course with the development of a peripancreatic mass, which is identified by CT. This lesion requires drainage and antibiotic coverage.
The complication of pancreatic pseudocyst results from pancreatic secretions and debris in the lesser sac. Symptoms may be those of a mass effect and may include gastric outlet obstruction with vomiting. The presence of a symptomatic mass in these patients requires decompression of the pseudocyst. However, if the pseudocyst is not symptomatic, it may be observed for up to 6 weeks, at which time, if there are no signs of spontaneous decrease in size, it should be drained. There is much controversy as to whether drainage should be conducted internally or externally. If the external route is chosen, percutaneous drainage may be done under ultrasound or CT guidance. In any event, if this technique is attempted and the catheter is incapable of draining the very thick secretions, internal drainage should be performed via pseudocystgastrostomy or cystenterostomy.64 Apart from the mass effect of the pseudocyst, these patients require frequent monitoring of the serum amylase level, which often remains elevated during the active phase when the pseudocyst is enlarging. Percutaneous drainage also is unlikely to be effective when the pseudocyst is multiloculated.
Acceleration-deceleration injuries are most likely to occur at points of fixation of the bowel, e.g., the ligament of Treitz, the ileocecal junction, and the rectosigmoid area. Blowout perforations of the small bowel, however, can occur at any site. Another mechanism for bowel perforation and injury is related to the lap seat belt. The presence of contusion on the abdominal wall from a lap seat belt often makes it difficult to assess the abdomen for signs of peritoneal irritation. In these circumstances, ultrasound or CT examination of the abdomen is quite helpful in determining whether or not there is a seat belt type of related intestinal injury. The presence of peritoneal signs will necessitate laparotomy. A high index of suspicion and aggressive investigation using ultrasound and CT are required to minimize missed small bowel injuries because these injuries occur frequently in the setting of other associated injuries.65–67
Treatment of injuries to the small bowel involves débridement of devitalized tissue and control of any associated bleeding points with primary suture. Devitalized areas may require formal resection of segments of bowel; this is usually followed by primary anastomosis with excellent results. The treatment of injuries to the colon depends on the time elapsed between injury and surgery, the degree of contamination, the stability of the patient, and the presence of associated injuries. If there is minimal gross contamination, the operation is being performed within 3 to 4 hours of the injury, and the patient is not in shock, primary anastomosis may be conducted safely. Devitalization of a large portion of the right colon often necessitates resection of the ileum and ascending colon with an ileocolic anastomosis. Left colonic lesions are more likely to be associated with frank fecal spillage. However, if there is very minimal spillage and no evidence of continued hemorrhage or associated injury, even these injuries may be treated by primary closure.68 Whenever there is doubt, however, the safest technique for treating left-sided colonic injuries is the fashioning of a colostomy together with repair of the laceration and irrigation of the peritoneal cavity. In situations where the lacerated bowel can be exteriorized, the resection may be performed and the ends of the bowel brought out as a proximal defunctioning colostomy and a mucous fistula. This technique is preferable to a defunctioning colostomy and Hartmann's procedure (oversewing of the rectal stump in the pelvis), which is associated with greater difficulty in subsequent reanastomosis of the large bowel.
Injuries to the rectum should be assessed in the operating room and frequently require general anesthesia with a proctosigmoidoscopic (preferably flexible) assessment to determine whether or not the anorectum has been perforated. Because of the propensity for major septic complications, particularly in the multiply injured patient, patients with possible perforating rectal injuries should be treated by a proximal defunctioning colostomy and the fashioning of a mucous fistula through which a catheter can be inserted for performing complete rectal washout.69 The irrigation of the rectum is conducted with the anus being held dilated. The perirectal space is then drained with appropriately placed drainage tubes. Once the gross fecal contents have been irrigated, the rectal mucosa and major lacerations should be repaired and the sphincter muscles reapproximated with interrupted sutures. This approach in the acute phase prevents retraction of the transected sphincter muscles, which makes later repair and maintenance of continence very difficult. Failure to adhere to the system of drainage, irrigation, and proximal defunctioning colostomy can lead to a protracted septic course with multiorgan failure and death from rectal injuries. A patient with a rectal injury with gross fecal contamination in the perineal area may require reexploration if the he or she continues to run a septic course in the ICU.
As indicated in Chapter 89, the abdomen remains a frequent source of sepsis in surgical patients in the ICU setting. These complications arise primarily after operations on the bowel, so any traumatized patient who has had bowel lesions treated surgically and who remains septic should be considered as having an intraabdominal source for that sepsis. This requires intensive investigation using modalities such as CT scan and ultrasound; drainable lesions may be treated by percutaneous techniques under CT or ultrasound guidance. When such techniques are contraindicated or are likely to be ineffective, or when the source is not obvious despite investigations, laparotomy may be necessary to identify and treat septic complications. With the availability of sophisticated technology in the form of CT and ultrasound investigations, it is usually possible to make a diagnosis prior to laparotomy, and only under very unusual circumstances is the lesion not identified prior to laparotomy.
One of the common areas of sepsis in patients with a perforated bowel is wound infection. Although the incisions in these patients frequently are left packed and open, in some instances the wound is closed primarily. The possibility of suppuration in the wound always should be considered at the first sign of sepsis, and the wound should be opened for diagnosis as well as treatment.70
Although liver injuries may occur from both blunt and penetrating trauma, patients with blunt injury to the liver tend to have a higher morbidity and mortality because of the irregular type of laceration and the involvement of an entire lobe or frequently both lobes of the liver. The signs of liver injuries are very nonspecific, and the diagnosis frequently is made only at laparotomy, the patient presenting with signs of intraabdominal hemorrhage. Liver hemorrhage is sometimes the chief cause of a patient presenting in hemorrhagic shock. Although diagnostic peritoneal lavage for hemorrhage may suggest liver injuries, it is not as specific as CT or ultrasound and is indicated in the hemodynamically compromised patient when FAST is not available or the patient cannot be transferred safely to the CT suite. Otherwise, these injuries are very clearly outlined by CT or ultrasound examination of the abdomen. Other signs that suggest the possibility of liver injuries include bruising of the lower chest, particularly on the left side; contusions over the upper abdomen; fractured lower ribs: an elevated hemidiaphragm; and increased size of the liver shadow on plain films of the abdomen. The usual indication for surgery in a patient with liver injury is intraabdominal hemorrhage.71
Although reported mortality rates from major liver trauma vary from 20% to 60%, most of the deaths are due to severe associated injuries, particularly of the head and thorax. When death is attributed to the liver injury itself, it is usually secondary to uncontrollable hemorrhage and later in the course is due to sepsis and multiorgan failure. Careful surgical technique and postoperative management of these patients will decrease the morbidity and mortality. The objectives of surgical management of liver injuries are (1) control of hemorrhage, (2) removal of nonviable tissue, and (3) provision of adequate drainage.
Exposure must be adequate, which necessitates a midline upper abdominal incision with the ability to extend into the chest. The liver itself should be mobilized completely by transection of the triangular ligaments, as well as the falciform ligament, with care taken to secure the inferior phrenic artery. The operative strategy should allow exposure of all structures that are likely to be injured or have an impact on management of the injury, including the vena cava and other retroperitoneal structures, and the surgeon must be prepared to perform the Kocher maneuver, right medial visceral rotation (Cattel and Braasch maneuver)72 and left medial visceral rotation (Mattox maneuver).73
In most instances, once the peritoneal blood has been aspirated, a nonbleeding hepatic laceration is identified. Such lacerations require drainage and no further surgical exploration. If hepatic bleeding is still active at the time of laparotomy, then the initial maneuver is to pack the liver area very tightly with dry gauze and continue with the remainder of the laparotomy for approximately 15 minutes. This allows time for stabilization of the patient's hemodynamic status, as well as time for replacement of fluid deficits. If, on removal of the pack, the bleeding has stopped, as is frequently the case, then the treatment is drainage of the perihepatic space. Failure to control bleeding by this technique necessitates clamping the portal triad, examining the wounds to determine the source of hemorrhage, and direct suture ligation of the bleeding points. Intermittent release of the clamp will allow examination for hemostasis. Hepatic artery ligation may be of benefit in some patients, although its effectiveness has been questioned.74 When bleeding arises from the retrohepatic vena cava, as evidenced when clamping of the portal triad fails to control the bleeding, it is necessary to rotate the liver medially and visualize the retrohepatic vena cava. Earlier reports have suggested the use of intracaval shunts to assist in preserving a dry field so that the injured hepatic veins and retrohepatic vena cava may be identified and repaired.75 However, recent data have shown a very high mortality associated with the use of the intracaval shunts, and aggressive hepatic packing has been an alternative that results in a better outcome.76,77 In extreme circumstances, complete vascular isolation of the liver by also clamping the suprahepatic and infrahepatic vena cava may be successful, although this maneuver frequently results in cardiac arrest in the already hypovolemic patient. Bleeding from through-and-through penetrating wounds of the liver also can be tamponaded by insertion of inflatable devices directly into the hepatic wound.78 In some instances, formal resection of liver tissue is required to control hemorrhage, particularly when there is major devitalization of liver tissue. This measure usually does not require formal anatomic lobectomy but instead consists of resectional débridement of the bleeding, devitalized liver tissue as demarcated by the edges of the laceration itself. The bare area of the liver is then treated with suture ligature, cautery, and the application of microfibrillar collagen or other types of topical hemostatic agents. In some instances, the patient may lose several units of blood as well as have other injuries that require attention. In addition, with the massive blood transfusions, the patient may show signs of coagulopathy. In such instances, it is advisable to pack the liver temporarily, close the abdominal wound, and correct the coagulopathy in the ICU with the hope of stabilizing the patient. The patient may then be taken back to the OR in 48 hours for removal of the pack, after which the bleeding will have either ceased or decreased considerably, allowing formal treatment of the bleeding source.79
Patients presenting with major liver injury frequently sustain other intraabdominal, thoracic, extremity, and head injuries. Such patients pose a great challenge to the surgeon and anesthetist. Massive blood transfusions with hemodynamic and respiratory compromise are seen in such patients, who become hypothermic, hypocoagulapathic, acidotic, and hypoperfused. These responses are not entirely confined to the patient with major liver injuries but also accompany other injuries to the chest and abdomen. In these circumstances, operative strategy should be directed at temporarily controlling hemorrhage and contamination by the most expeditious means and allowing the patient to return to the ICU setting, where the cardiorespiratory, renal, metabolic, hypocoagulable, and hypothermic states can be monitored and corrected before returning the patient to the OR for more definitive surgical care. In the setting of abdominal injuries, this involves control of hemorrhage by packing and ligation of vessels without attempts at formal repair, as well as ligation and temporary stapling of injured bowel ends with evacuation of intestinal contents by suction, followed by temporary rapid skin closure of the abdomen. Similar damage-control techniques for thoracic injuries, including tractotomy and quick stapling of vascular and bronchial structures, allow the patient to return to the ICU environment for correction of these immediately life-threatening abnormalities before being returned to the OR for formal, definitive surgical repair of the injuries.79–82
Resection of Devitalized Tissue
Formal hepatic lobectomy is seldom necessary for trauma. Resection usually is confined to removal of frankly nonviable tissue. The area for resectional débridement usually is well demarcated by the nature of the liver laceration itself. Manual compression is maintained on the liver while the resection is conducted to control hemorrhage. Intermittent packing and compression of the liver are required to allow volume resuscitation of the patient during the procedure.
The lacerated liver continues to drain bile, blood, and tissue fluid for a considerable period postoperatively. Accumulation of this fluid in the peritoneal cavity is prevented by appropriately functioning peritoneal drains. T-tube drainage of the common bile duct is not required unless there is a central ductal injury requiring surgical repair or unless the common bile duct is enlarged because of previous pathology.
During the postoperative period, these patients frequently run a febrile course, which makes it difficult to determine whether or not there is underlying sepsis. Therefore, antibiotics frequently are administered in the immediate perioperative period. With major hepatic resection, glucose infusions are required to treat hypoglycemia, and hypoalbuminemia needs to be treated temporarily with plasma and albumin infusions until the nutritional status of the patient is improved. Coagulation defects are treated with fresh frozen plasma, vitamin K supplements, and platelets when indicated. Most of these patients also develop some degree of jaundice, which usually is transient but may last from several days to several weeks. Because many of the signs indicated earlier are common in uncomplicated liver injuries, the presence of septic complications may go unnoticed. Frequent radiologic investigation and monitoring of the WBC count are necessary, and baseline estimate of these parameters would allow one to determine whether the patient is progressing satisfactorily or not. A patient whose bilirubin level and WBC count are decreasing but who suddenly shows an increase in serum bilirubin level or has a spike in temperature should be investigated carefully for a source of sepsis in the abdomen. Another complication that may arise in hepatic injury is hemobilia, which may present with upper gastrointestinal hemorrhage, as evidenced by hematemesis or blood-stained nasogastric drainage. This lesion requires immediate investigation in the form of hepatic angiography and CT or ultrasound examination. Once the source of the intrahepatic hemorrhage is identified, hepatic artery embolization or balloon tamponade is a viable option for controlling the hemobilia83 before formal hepatic resection is considered.
Injuries to the spleen should be suspected in patients who present with left upper quadrant pain, especially in the presence of left lower rib fractures. There may be associated shoulder tip pain on the left side. A frequent mode of presentation, however, is a patient with signs of massive intraperitoneal hemorrhage requiring immediate laparotomy for hemorrhagic shock. In situations where the signs are equivocal, ultrasound examination may be diagnostic. CT of the abdomen in an otherwise stable patient also will identify splenic injury. Most patients who are able to maintain adequate hemodynamics with minimal requirements for blood transfusions, particularly children, can be treated conservatively without the need for laparotomy.84 Such patients should be monitored very closely in the ICU setting for signs of continued blood loss and requirement for continued fluid infusions. Although imaging techniques have been attempted to identify splenic injury patients that will require surgical intervention, the most important determinant of the need for surgical intervention remains the hemodynamic status of the patient and the requirement for continued fluid infusion.85 Where the patient's condition allows, angiography can identify bleeding vessels that may be embolized to control bleeding from the traumatized spleen.86 Currently, nearly all children and 50% to 80% of adults with blunt hepatic or splenic injuries are treated without laparotomy.87 Whenever there is a suggestion of associated injury or there is an acute splenic injury in an adult who is severely compromised hemodynamically, laparotomy is advised.
At laparotomy, the aim should be to control hemorrhage, with splenic salvage if possible. In order to assess the splenic injury adequately, complete mobilization and delivery of the spleen into the wound are necessary. Superficial supcapsular tears of the spleen may be treated by initial packing for approximately 15 minutes. Failure to control the hemorrhage by this means will necessitate such techniques as the application of microfibrillar collagen or fine sutures. Identifiable bleeding points are coagulated as well as suture ligated, particularly when bleeding points occur near the hilum of the spleen. Ligation of the short gastric vessels in certain instances also will arrest splenic hemorrhage. In some instances, a lacerated portion of the spleen may be excised, with suturing of the remainder of the spleen with large chromic sutures with Teflon pledgets for securing the sutures. When multiple lacerations are evident, it is possible to control the hemorrhage by placing the spleen in a net of Dexon mesh, which can be tightened to produce compression and control of hemorrhage.88 If control of hemorrhage by a combination of these techniques is impossible, then splenectomy should be conducted. Also, if the patient remains unstable from other major injuries and bleeding from the spleen is a major problem, splenectomy should be conducted most expeditiously to decrease the operating time and improve the patient's chances of survival.
Postsplenectomy patients are very prone to septic complications, particularly from infections associated with the encapsulated pneumococcous, Haemophilus influenzae, and Neisseria meningitidis. Prior to discharge from the unit, these patients should be vaccinated against these organisms. Patients also should be warned that any infective process is cause for seeking medical attention because of the increased risk of overwhelming sepsis in splenectomized patients.89 One of the areas of concern in monitoring patients after splenectomy in the ICU is the frequent occurrence of leukocytosis and thrombocytosis. This situation makes monitoring for intraabdominal sepsis difficult, and one has to follow the WBC count until it plateaus. A deviation or a sudden increase from a plateau high WBC count could be considered evidence of occult sepsis. In patients who are in the ICU for prolonged periods with platelet counts above 106/μL, consideration should be given to prophylactic anticoagulation to prevent thrombotic complications.
Injuries to the Extrahepatic Biliary Tract
These injuries are relatively infrequent. Common bile duct injuries commonly involve the other structures in the porta hepatis, with frequently associated injury to the liver, duodenum, or other structures in the abdomen. Vascular injuries isolated to the porta hepatis are relatively rare and carry a very high mortality rate. If a porta hepatis injury is suspected, the Pringle maneuver would allow better identification of the injury with dissection of the structures of this area. Vascular injuries take priority over duct injuries because of the immediate threat to survival posed by massive hemorrhage. If the portal vein is the source of the hemorrhage, then attempts should be made to repair this by lateral venorrhaphy, resection, and anastomosis or interposition grafting. Portal systemic shunting usually results in severe encephalopathy in previously healthy patients with normal hepatic flow and should be avoided if possible. Common hepatic artery injury should be repaired where possible; otherwise, ligation may be performed as a last resort.90,91
Common bile duct injuries that involve less than 50% of the circumference of the duct should be treated by débridement and primary closure with a stent (a ureteric stent or T-tube) exiting away from the anastomosis. If more than 50% of the circumference of the bile duct is involved, then there is an over 50% rate of late stricture that diminishes to about 5% if a biliary enteric anastomosis is performed.
Injuries to the gallbladder should be treated by cholecystectomy unless the patient's hemodynamic status is precarious, when a cholecystostomy may be performed as a temporizing measure.92,93
Frequently, hemorrhage in the retroperitoneal space is identified at laparotomy. This problem can be very difficult to treat, and when possible, preoperative investigation including x-ray of the pelvis, CT scan, or angiography will allow consideration of specific diagnostic possibilities and a more directed surgical approach. When the patient is taken to the OR prior to any of these investigations because of instability, however, a decision needs to be made regarding proper treatment of the retroperitoneal hemorrhage.
Division of the retroperitneum into three zones may be used to guide therapeutic decisions (zone 1, central; zone 2, lateral; zone 3, pelvic). In general, hemorrhage that is associated with a major pelvic fracture and confined to the pelvis or originating in the pelvis should be treated without exploration unless either there is a penetrating injury that is likely to involve the iliac vessels or the hematoma is pulsatile.94,95 Exploration of such retroperitoneal hematomas usually results in massive uncontrollable hemorrhage when the source is the pelvic fracture. This type of hemorrhage often is best treated by external fixation of the fractured pelvis and blood transfusions. Angiography is required when hemorrhage is continuing with a view to embolizing any identifiable bleeding artery. The mainstay of controlling hemorrhage from pelvic fractures, however, is immediate stabilization of the pelvis to prevent undue motion of the fracture fragments, and this is accomplished most expeditiously by external fixator application.96
Apart from hematomas arising from the pelvis, hematomas that are not pulsatile or expanding and that are located in the lateral retroperitoneal spaces (zone 2) also should be left unexplored, and further investigation should be done postoperatively in the form of contrast-enhanced CT scan and angiography as indicated. If the lesion is expanding or pulsatile, the retroperitoneal space has to be explored to identify the bleeding source and control it. Temporary control of an infradiaphragmatic source of hemorrhage can be achieved by thoracotomy and clamping of the supradiaphragmatic aorta.47 However, when the hematoma or bleeding does not extend to the aortic hiatus, temporary control may be achieved within the abdomen by compressing the aorta at the diaphragmatic crura. This compression can be done by an assistant's hand, an aortic compressor, or a sponge stick. By incising the peritoneum and mobilizing and displacing the esophagus, a clamp also may be applied directly to the aorta to achieve temporary control of intraabdominal hemorrhage.97
A retroperitoneal hematoma that is centrally located (zone 1) in the midabdomen represents possible injury to the pancreas and major retroperitoneal vessels. These hematomas require exploration with a view to determining the extent of the injury and, in the case of the pancreas, to determine whether the pancreatic duct has been violated. The lesion is then treated as outlined earlier for pancreatic trauma. Surgical exposure strategies are as outlined previously to allow adequate visualization of retroperitoneal structures as well as vascular control.
Occasionally, retroperitoneal hemorrhage, particularly in the pelvis, cannot be controlled by surgical means, and one has to resort to packing of the retroperitoneal space and closure of the abdomen with a view to exploring the patient within 48 hours, hopefully after cessation of the bleeding. These patients require very close observation in the ICU with correction of any coagulopathy, acidosis, hemodynamic derangement, and hypothermia.66
Although hematuria is absent in 5% to 10% of patients with genitourinary trauma,98 it still is a most important sign of genitourinary injury. The patient frequently has sustained blunt or penetrating injury to the flank or diffuse transfer of force to the abdomen. Occasionally, there is a direct penetrating injury into the bladder or kidney. Penetrating injury resulting in ureteric lacerations is very rare, and where possible, these injuries are repaired by débridement, primary repair, and stenting. Although in the past traumatic hematuria of any degree has been investigated with IV pyelography, a more selective approach is more appropriate. This change in approach has resulted from the low yield of IV pyelography in all patients with trauma; also, in the presence of hematuria, the yield in terms of positive lesions identified varies from 15% to 60%.99 Most of the injuries discovered (65% to 70%) are considered minor, involving a parenchymal laceration or contusion that does not require surgical intervention. Major parenchymal laceration through the corticomedullary junction and often into the collecting system usually causes gross hematuria and represents 10% to 15% of renal injuries.100 The remainder of renal injuries are associated with a shattered kidney or renal pedicle injury. These considerations, together with the cost of the procedure, as well as the incidence of allergic reaction (5.7%), including anaphylaxis, renal failure, and death (0.0074%), have led to a change in the approach to hematuria in the assessment of genitourinary trauma. In most instances, the major cause of death from genitourinary trauma is the associated injuries, and the investigation using IV pyelography has had very little effect on management or outcome in general.
Microhematuria without shock has not been shown to be associated with lesions requiring surgical intervention, whereas gross hematuria or microhematuria with shock or a major abdominal injury has been associated with lesions requiring surgery in up to 10% of cases.99,100 Penetrating renal injuries are associated with lesions requiring surgery both with and without hematuria.100 On the basis of these observations, IV pyelography should not be routine in abdominal trauma.101 Also, if the patient is having a CT scan of the abdomen for another reason, or if there is only microhematuria without shock or any evidence of severe injury, IV pyelography is not recommended. The IV pyelogram, however, is helpful in the following circumstances: (1) if a CT scan is not being done and there is gross hematuria or microhematuria with shock, (2) if there is hematuria in the presence of a major abdominal injury, or (3) if there is a penetrating injury and the trajectory suggests the possibility of renal injury, even without hematuria. One other relative indication for IV pyelography is if the patient is unstable but hematuria is present; if time allows, a one-shot IV pyelography may be conducted to assess the functioning of both kidneys in the event that nephrectomy may be required during laparotomy.
The main indication for surgical intervention in renal trauma is an injury with major hemorrhage such that the patient's hemodynamic stability cannot be maintained with rapid transfusion of crystalloid and blood. Otherwise, most patients with renal trauma are treated nonoperatively (Fig. 95-8) at first. They should be observed very closely in an ICU setting for any deterioration in hemodynamic status suggesting continued major hemorrhage that requires surgical intervention. If there is failure to visualize both kidneys on IV pyelography, then contrast-enhanced CT or angiography should be conducted to determine the extent of the injury producing nonfunctioning of the kidneys.
Spontaneous resolution of renal injury. A. Intravenous pyelogram showing extravasation of contrast material immediately after blunt trauma with hematuria. B. Repeat intravenous pyelogram after 5 days of observation shows no extravasation.
The main principle in surgical treatment of kidney injury is to control hemorrhage while preserving kidney function; this is best achieved by exploring the kidney only in selected patients in whom there is an expanding of pulsatile hematoma or signs of urine extravasation. In order to ensure adequate hemorrhage control, the renal vascular pedicle should be isolated first and secured to allow occlusion if this becomes necessary. If after attempts at repair or partial nephrectomy there is still massive bleeding after release of renal pedicle occlusion, then nephrectomy becomes necessary, especially in the unstable patient who is known to have a contralateral normal kidney.
Hematuria also may result from injury to the bladder, and the suspicion of bladder injury should be investigated by cystography, at least three views being taken with the bladder both filled and emptied to determine whether or not there is any extravasation of bladder contents. Retrograde cystography has been reported to be more accurate in diagnosing bladder injuries than the spiral CT.102 Extraperitoneal bladder rupture may be treated by catheter drainage alone, whereras intraperitoneal bladder rupture usually warrants open laparotomy with débridement and formal repair of the laceration.103,104
Although in most multiply injured patients urinary catheterization per urethra is routine for monitoring the urine volume and consistency as a reflection of the hemodynamic status, there are certain contraindications to catheterization per urethra. Blood at the urethral meatus or the presence of scrotal or perineal hematomas with a large, high-riding, boggy prostate may signal injury to the urethra; these findings necessitate a urethrogram to exclude urethral laceration prior to transurethral placement of a Foley catheter. Urethral rupture necessitates urologic consultation and treatment.
Postoperative care of these patients requires maintenance of renal perfusion; thus careful attention to maintenance of hemodynamic stability is important. In addition, maintenance of good urinary output and close monitoring of the degree of hematuria, as well as the volume of urine, are required in the ICU setting. An occult injury to the genitourinary tract with extravasation of urine that is left undiagnosed is another means by which a multiple-trauma patient may develop septic complications in the ICU. This type of complication is diagnosed by ultrasonography or CT and is treated by drainage of the urinoma with or without repair of the source of the urinoma.
Traumatic Abdominal Compartment Syndrome
Although the deleterious effects of increased intraabdominal pressure have been identified prior to the twentieth century,105 improvements in prehospital care and the rapidity with which multiply injured patients are taken to the OR room have led to an increased recognition of the syndrome caused by acute increases in intraabdominal pressure (see Chap. 42) because this syndrome is more likely to occur in the presence of multiple major intraabdominal injuries resulting in severe blood loss, massive fluid requirements, and prolonged surgery. Previously, most of these patients would not survive to reach the operating room. The traumatic abdominal compartment syndrome may be defined as the adverse clinical consequences of an acute increase in intraabdominal pressure following trauma. The generally accepted parameters for defining this syndrome include an increase in intraabdominal pressure above 20 cm H2O, peak airway pressure of greater than 40 cm H2O, oxygen saturation of less than 90% on 100% oxygen, and oxygen delivery index of less than 600 mL/m2 per minute, as well as oliguria of less than 0 .5 mL/kg per minute.106 The condition is diagnosed usually at the end of a surgical procedure when attempts are made to close the abdomen or early in the postoperative period of the massively injured patient, although it may occur in patients with major intraabdominal hemorrhage or retroperitoneal hemorrhage prior to surgical intervention. The source of the increased intraabdominal pressure is usually edema, blood accumulation, or distention of the hollow viscera. Prevention of this syndrome therefore is achieved by minimizing intraabdominal edema through decreasing the period of hypotension, minimizing manipulation of the bowel, limiting the duration of surgical procedures, adequate control of hemorrhage, and appropriate decompression of the gastrointestinal tract.107
In the setting of hemodynamically compromised patients requiring massive blood transfusions leading to hypocoagulability states, acidosis, and hypothermia, major definitive surgical procedures should be postponed in order to eliminate factors that predispose to increases in intraabdominal pressure. The concept of damage-control laparotomy is therefore an important consideration in this setting.79–81
The increase in intraabdominal pressure affects virtually all systems in the body,108,109 including a decrease in cardiac output from the decrease in venous return arising from compression of the vena cava, decreased renal perfusion, decreased myocardial perfusion, and increased airway pressure resulting in inability to mechanically ventilate and maintain oxygenation of the patient—all of which are associated with a poor outcome unless the increase in intraabdominal pressure is treated promptly by abdominal decompression. In the OR, apart from the practice of damage-control laparotomy, if on attempting formal closure of the abdomen there is major increase in intraabdominal pressure, as reflected by an extraordinary increase in airway pressures with difficulty in ventilating the patient, the formal closure should be aborted. In these circumstances, the abdominal contents are contained by using temporary devices such as plastic bags sutured to the edges of the skin. In some instances, skin closure without fascia closure may be possible without a major increase in intraabdominal pressure. The patient is returned to the ICU for stabilization, monitoring, and correction of associated abnormalities. With improvement in these parameters and signs of reduction in the intraabdominal pressure, the patient is returned to the OR for further surgical intervention, which may allow either primary closure of the fascia with skin closure or the use of mesh for closing the fascia followed by skin closure or skin grafts later on. Other more elaborate techniques of abdominal wall closure are required in the long term for these patients.110,111
Apart from recognition of this entity in the OR, it may develop slowly or abruptly without previous surgery (e.g., the patient with major retroperitoneal hemorrhage from a pelvic fracture) or in the postoperative period during the patient's ICU stay. In a patient in whom this syndrome is likely to develop, close monitoring of airway pressures, hemodynamics, renal perfusion, gas exchange, and intraabdominal pressure is required. A simple means of monitoring intraabdominal pressure is by attaching a three-way stopcock to the side tubing of a Foley catheter after instilling 50 to 100 mL of sterile saline into the bladder through the catheter. On clamping the Foley catheter tubing distal to the three-way stopcock, the stopcock is opened to a manometer that is zeroed at the level of the symphysis pubis.112
The mainstay of treatment of patients with this traumatic abdominal compartment syndrome is immediate abdominal decompression, which can be performed in the ICU. Without decompression, mortality is prohibitive and arises from the development of cardiopulmonary failure, renal failure, hepatic failure, and bowel ischemia.
Patients at particularly high risk of developing this entity include those with massive retroperitoneal hematomas from conditions such as pelvic fractures and those with major intraabdominal hemorrhage requiring prolonged operative procedures, the use of massive amounts crystalloids and blood transfusions leading to hypothermia and hypocoagulable states. Treatment should be directed at correction and prevention of these precipitating factors. A high index of suspicion should be maintained in order to predict the onset of this condition so that preventive measures and early diagnosis will result in prompt abdominal decompression.