0039-6109/90 $0.00
Abdominal Trauma
+ .20
Postoperative Complications of Abdominal Trauma
Anna M. Ledgerwood, MD, * and Charles E. Lucas, MD*
Successful treatment of severe intra-abdominal injuries not only prolongs the useful lives of patients, but also provides a source of immense pleasure and satisfaction to the operating surgeon. Nothing disrupts this postoperative euphoria more than the evolution of a complication, especially when this complication is found, by subsequent study, to have been preventable. Trauma surgeons appear to surpass all others in attributing their complications to inadequate exploration, inappropriate decision making, technical misadventure, or poor perioperative care. The detrimental effects that hemorrhagic shock, massive blood transfusions, diffuse peritoneal soilage with feces and urine, and the unavoidably rough handling of tissue have on the normal physiologic defense mechanisms must be recognized. The ability of the body to handle such a massive peritoneal insult is astounding. One is not surprised that a second peritoneal insult from a leaking colon repair occurring during the inflammatory healing phase of the first insult is not well tolerated and may lead to multiple organ system failure and death. The objective is to identify those factors that can minimize the magnitude of the initial insult and decrease the likelihood of a second or third insult, which tips the scale against patient survival. The incidence of complications after abdominal trauma can be reduced by attention to protocol regarding resuscitation, priorities in diagnosis and treatment, antibiotic usage, and timely placement of tubes in body orifices. Efficient resuscitation with prompt operative intervention reduces the hemorrhagic shock insult and the extent of peritoneal spillage from hollow viscus perforation, thus minimizing the threat to the immunologic system. Proper preoperative assessment circumvents the need for intraoperative *Professor, Department of Surgery, Wayne State University, Detroit, Michigan This article was supported by the Interstitial Fluid Fund, Account No. 4-44966.
Surgical Clinics of North America-Vol. 70, No.3, June 1990
715
&
716
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
diagnostic studies performed with the abdomen open, which prolongs the anesthetic insult. For example, evaluation of hematuria during resuscitation avoids the need for intraoperative pyelography or aortography. The institution of preoperative antibiotic therapy in all patients with penetrating abdominal trauma and selected patients with blunt abdominal injury enhances the endogenous defense mechanism against infection. 3 More important than the specific antibiotic regimen is the recognition that postoperative infectious complications are reduced when antibiotics are initiated when the patient is first seen rather than after the abdomen is opened. Preoperative placement of chest tubes for suspected hemothorax reduces the chances for intraoperative pulmonary embarrassment. Preoperative nasogastric decompression decreases the likelihood for vomiting and aspiration. Any insult to one organ, especially the lungs, enhances the risk of complications elsewhere, including the abdomen. Intraoperative activities likely to reduce postoperative complications from abdominal trauma include care in the handling of body tissue, especially the intestines. When faced with the combined insult of active hemorrhage and overt leakage of bowel contents into the peritoneal cavity, control of bleeding carries the higher priority. Temporary control of bleeding by pack tamponade over an injured liver often allows for rapid closure of hollow viscus injuries, thereby decreasing the bacterial challenge. When this approach is feasible, a single-layer running closure of all hollow viscus perforations should be performed rapidly, after which the liver pack can be removed and definitive hepatic hemostasis achieved. Attention can then be directed back to the hollow viscus injuries for a second-layer or outer-layer closure. During the initial exploration, the small intestine often needs to be eviscerated and retracted to localize and control active hemorrhage. Once active life-threatening bleeding is contained and hollow viscus injuries are closed, the intestine should be returned to the abdomen with further retraction accomplished by deftly placed packs. This technical aid greatly reduces the extent of intraluminal and intramural bowel swelling and the severity of postoperative adynamic ileus. Postoperative complications in the patient with multiple injuries may be difficult to detect. Fever, leukocytosis, and abdominal distension may be from the laparotomy or from an extra-abdominal problem. Likewise, multiple organ system dysfunction may be a sign of an intra-abdominal and/ or extra-abdominal problem. Confirmation of an intra-abdominal complication often requires a second laparotomy. This decision may be difficult for the original surgeon, who may be confused by a combination of bias, ego conflict, frustration, and fatigue. A mature, well-rested surgeon who was not present at the original operation often can provide a nonbiased assessment regarding the need for reoperation. The original surgeon should participate at the second operation, if deemed advisable, and welcome the technical and moral support of the consultant surgeon.
POSTOPERATIVE HEMORRHAGE The most common complication occurring in the first 24 hours after operation is hemorrhage. Postoperative bleeding in a patient with minimal
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
717
injury and no shock will usually be within the peritoneal cavity and generally arises from the areas of previous dissection. This patient will have unexpected tachycardia, hypotension, abdominal distension, and anemia in the recovery room. Immediate reoperation identifies the source of bleeding, which usually is easily controlled. Intraperitoneal hemorrhage more commonly occurs in patients with at least moderate intraoperative transfusion requirements to correct unstable vital signs. Often these patients are marginally stable at the end of the initial operative procedure, so that unclamped but open blood vessels are not readily identified, clamped, and ligated. The hypotensive patient has what appears to be a relatively dry operative field near the end of an operative procedure because perfusion pressure is insufficient to cause frank bleeding through uncontrolled vessels. Consequently, such patients may be closed when there is minimal oozing, which becomes active arterial bleeding when the blood pressure is restored in the recovery room. The patient recovering from a moderate blood loss (2 to 10 transfusions intraoperatively) most likely has postoperative bleeding from incomplete surgical hemostasis. Assessment of platelet function (primary hemostasis) and the coagulation cascade leading to a fibrin clot (secondary hemostasis) helps identifY a coexistent nonsurgical bleeding problem. A platelet count above 75,000/mm 3 and a bleeding time under 9 minutes ensure adequate primary hemostasis, whereas a normal prothrombin time and partial thromboplastin time ensure adequate secondary hemostasis. 4 Furthermore, the patient should be warmed to normal body temperature. Hypothermic patients may have prolonged bleeding times and defective platelet aggregation, which correct with rewarming. When thrombocytopenia and a prolonged bleeding time are present, platelet infusion should be planned in conjunction with re-exploration. When the prothrombin time and partial thromboplastin time are prolonged, fresh frozen plasma infusion should be instituted. Most patients with postoperative bleeding have had severe hypovolemic shock, for which massive transfusions (10 to 30 units) are needed. Some patients are likely to have combined defects in both primary and secondary hemostasis, requiring both platelet and plasma therapy. Such patients may also have surgical bleeding, so that correction of the defects in hemostatic function is done in concert with re-exploration. A small number of severely injured patients will have bleeding that cannot be completely controlled at the initial operation such that packing is required. This is particularly true with massive liver injuries or retroperitoneal hemorrhage secondary to pelvic fracture. These patients almost invariably receive more than 25 transfusions during a prolonged operative procedure, leading to hypothermia below 34° C. When packing is necessary, the abdomen should be closed without drains or stomas. These patients almost always have impaired primary and secondary hemostasis with abnormal platelet aggregation, thrombocytopenia, and prolonged bleeding times, prothrombin times, and partial thromboplastin times. Such patients are taken to the intensive care unit, where they are rewarmed and their clotting deficiencies corrected. These patients have a planned second operation 24 to 48 hours later, when the packs are removed and definitive hemostasis is obtained.
"-SMII
718
M..
uk
ANNA
M.
LEDGERWOOD AND CHARLES
f
E.
LUCAS
MISSED ABDOMINAL INJURY Exploratory laparotomy for blunt and penetrating trauma requires discipline in a thorough exploration of the peritoneal cavity to detect all injuries. Once all identified injuries have been treated, a last look at sites and organs in a systematic manner removes the threat of missed injury. This last exploration is facilitated by a keen sense of paranoia and knowledge of the likely sites for missed injury. Such areas include the cardioesophageal junction, where injuries to the distal esophagus are not easily identified, particularly after penetrating wounds. Extra care is needed when examining the cardioesophageal junction and the posterior wall of the proximal stomach along the lesser curvature. This may require division of the gastroepiploic vessels along the greater curvature of the stomach, thereby permitting anterior rotation of the greater curve and visualization of the entire posterior gastric wall. Diaphragmatic rupture is commonly overlooked in patients with penetrating abdominal wounds. The origins of the diaphragm extend inferiorly to the second lumbar vertebra and are often not fully appreciated by the unwary surgeon who has just finished repairing an injured pancreas or colon in that region. Such patients may develop postoperative bleeding but are more likely to develop a hemothorax. Chest-tube thoracostomy will correct the hemothorax in many patients, but others with subdiaphragmatic infections will also develop empyema. 14 When these injuries are seen during the initial procedure, suture closure prevents, in most instances, the intrathoracic extension of infection. Missed diaphragmatic injury after laparotomy for blunt abdominal trauma is less common. The authors have had the opportunity to treat such a patient who had a laparotomy performed for a positive peritoneal lavage. The initial chest film was interpreted as being normal (Fig. 1). Laparotomy revealed a longitudinal laceration in the liver paralleling the falciform ligament. This was interpreted as the source of bleeding, which produced a positive peritoneal lavage. Hepatorrhaphy was achieved without incident, and the abdomen was closed. The postoperative course was complicated by fever and atelectasis (Fig. 2). A blunt rupture of the diaphragm was obvious by day 4 (Figs. 3 and 4), when the patient's respiratory distress worsened. Reoperation identified a 4-cm tear just to the left and anterior to the esophageal hiatus. Presumably, the left lobe of the liver hid this tear during the initial exploration. More likely, the operating surgeon relaxed after successfully controlling liver bleeding and neglected to perform the last preclosure exploration. Fortunately, the patient did well after reoperation and diaphragmatic repair. Missed injury to the extrahepatic biliary tree is avoided by careful inspection of the porta hepatis. One should look for hematoma or bile staining and perform a complete Kocher manuever to visualize the retroduodenal bile duct in patients with penetrating wounds in proximity or suspicious findings after blunt injury. Blunt bile duct injury usually occurs in the retroduodenal segment but may also occur in the right or left hepatic ducts. A missed injury may present with bile drainage through drains placed for other injuries. In the absence of drains, such patients are likely to develop the combination of fever, leukocytosis, bile-stained ascites, and
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
719
Figure 1. This patient had blunt trauma following an auto accident. This chest roentgenogram, which was obtained at admission, was interpreted as normal by the radiologist and the trauma surgeon.
jaundice. Endoscopic retrograde pancreatography (ERCP) identifies the anatomic defect and guides corrective operative intervention. Missed duodenal injury usually occurs in patients not explored, despite the clinical and roentgenographic findings indicative of duodenal rupture from blunt trauma. Penetrating duodenal perforations may be overlooked when they too are located on the posterior wall or along the mesenteric border adjacent to the pancreas. Complete examination of these areas is facilitated by inferior reflexion of the hepatic flexure of the right colon and full duodenal Kocherization. Postoperative findings likely to occur with unrecognized duodenal rupture include the typical findings of intra-abdominal sepsis, which rapidly progresses to systemic sepsis and threat of death. Diagnosis may be confirmed by upper endoscopy or an upper gastrointestinal contrast study with or without an abdominal computed tomographic (CT) scan. Once confirmed, the authors prefer closure of the duodenal perforation in conjunction with vagotomy, antrectomy, gastrojejunostomy,
720
ANNA
M. LEDGERWOOD AND CHARLES E. LUCAS
Figure 2. This chest roentgenogram was obtained on the second postoperative day for fever and suspected atelectasis. It was interpreted as shOwing gastric distention.
tube duodenostomy, and periduodenal drainage. 7 Other authors may advocate a less aggressive approach, depending upon the degree of injury and sepsis. Prevention of a missed pancreatic injury demands thorough lesser sac exploration and examination of the pancreas throughout its length. Injury to the main pancreatic duct is often difficult to detect. If the patient has blunt injury with transection of the pancreas overlying the vertebral column, duct injury is usually obvious. Penetrating wounds of the superior portion of the pancreas may involve the main pancreatic duct. If pancreatic juice flows from the wound, injury to the main duct is assumed and the pancreatic injury is treated accordingly. If no drainage ensues from the wound, simple drainage should be performed. Postoperative recognition of a missed pancreatic injury is made on the basis of peritoneal drainage containing a high amylase. When no drainage is used, the patient with a missed injury will develop the clinical and roentgenographic picture of lesser sac sepsis, similar to the clinical syndrome of an early pancreatic pseudocyst. Diagnosis
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
721
Figure 3. The chest roentgenogram was obtained on the fourth postoperative day for shortness of breath. This was interpreted by the radiologist as showing atelectasis and gastric distention. The trauma surgeon questioned the possibility of a diaphragmatic rupture.
of missed pancreatic injury is confirmed by ERCP, which also guides therapeutic intervention. When a missed pancreatic injury is combined with an associated hollow viscus perforation, the activation of proteolytic enzymes leads to overwhelming lesser sac inflammation, which demands early intervention. Missed injury to the colon or rectum may be devastating. A colon perforation most frequently will be missed because of inadequate mobilization and evaluation of the retroperitoneal colon. One cannot rule out, with certainty, retroperitoneal rectal injury from an intra-abdominal examination. Thus, preoperative assessment is crucial. The authors assume a rectal injury is present if there is blood on the examining finger, blood obtained with a Fleet enema prior to sigmoidoscopy, or blood seen on sigmoidoscopic examination when no other colon lesions are seen during laparotomy. Rectal injuries are treated with a proximal colostomy and drainage of the presacral space. Missed rectal injury leads to progressive pelvic sepsis, which in some patients extends retroperitoneally to the kidney, causing extensive sepsis, which is life threatening. Diagnosis is suspected clinically and by roentgenographic plain films or pelvic CT scan.
722
ANNA
M. LEDGERWOOD AND CHARLES E. LUCAS
Figure 4. An upper-gastrointestinal series was done that confirmed gastric herniation through a ruptured diaphragm.
Diagnosis is confirmed by endoscopy or contrast radiography. Endoscopy is preferred because the mixture of feces and barium in the retrorectal space acts synergistically to create overwhelming infection. Treatment consists of prompt proximal diversion and retrorectal drainage through the perineum. Ureteral injuries may be missed if there is not careful evaluation of the trajectory of missiles in the retroperitoneum. Likewise, injury to arteries and veins may be missed if the bullet track is not carefully evaluated as it enters the retroperitoneal area. Significant vascular injuries may occur with minor retroperitoneal hematomas. Thus, the path of the bullet should be exposed when the bullet has passed near the medially located major blood vessels. An arterial venous fistula of the iliac artery and vein may go undetected at the initial operation because the arterial blood leakage Hows directly into the vein without forming a perivascular hematoma. An example is a patient who had a very small hematoma in the area of the bullet where
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
723
it traversed the retroperitoneum and was not initially explored (Fig. 5). Postoperatively, the patient had a mechanical small bowel obstruction treated by lysis of adhesions. Again, no injury to the vessels was detected. The medical student caring for this patient noted a strange noise in the abdomen when listening for bowel sounds and called this to the attention of his more senior colleagues. This patient required a third operation for repair of his arteriovenous fistula.
WOUND COMPLICATIONS: INFECTION, NECROTIZING FASCIITIS, AND WOUND DEHISCENCE Wound infection following laparotomy for abdominal trauma is not uncommon. The combination of hemoperitoneum, devitalized tissue, and bowel perforation leads to significant bacterial contamination of the abdominal wound. Patients requiring laparotomy for blunt and penetrating trauma are treated preoperatively with broad-spectrum antibiotics. Such antibiotic
Figure 5. This patient sustained a gunshot wound of the abdomen that caused injuries to the small bowel 6 weeks previously. There was only a "small" retroperitoneal hematoma, and it was not explored. This aortogram was obtained because of an abdominal bruit heard on the fifth postoperative day, follOwing lysis of adhesions for a mechanical small bowel obstruction 6 weeks after the original injury. It demonstrates an arteriovenous fistula between the external iliac artery and vein. This injury was not detected at the original operation because the path of the bullet was not fully evaluated.
724
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
therapy will decrease the incidence of wound infection if the contamination is not excessive. Consequently, primary skin closure is avoided in patients who have colon injury with spillage (greater than 5 ml), moderate spillage from the small intestine or stomach (greater than 30 ml), or hypotension and massive transfusions (greater than 8 units). These patients are prone to develop wound infection, which can easily be prevented by simply leaving the skin open. Delayed primary closure can be performed by the fourth day if the patient is doing well and the wound looks good. Necrotizing fasciitis is the sequela to a wound infection that remains unrecognized and untreated. These patients often have had a fever on the third or fourth postoperative day. When the wound is finally opened on the fifth through the ninth postoperative days, there is foul-smelling drainage, with dissection of the bacteria along the fascia causing fascial necrosis as the virulence of the bacteria exceeds the defense of the hypaperfused fascia. This serious complication almost always leads to wound dehiscence and sometimes evisceration. These patients will almost always require a secondary procedure for debridement of the fascia and secondary wound closure. Necrotizing fasciitis may also occur when the skin is left open to heal by secondary intent. This problem occurs in patients with severe injury requiring multiple blood transfusions for prolonged hypotension and blood loss. Usually these patients have had very long operative procedures and generalized swelling that includes the abdominal viscera, especially the intestines. This generalized edema leads to loss of the abdominal wall compliance. The abdominal wound may be closed with "slight tension." When additional fluid and blood are required in the postoperative period and the abdomen swells further, the abdominal wall fascia is placed under undue tension as the swollen abdominal contents push against the wound. The fascia is always clearly visible because the skin has been left open. The portion of fascia included within the sutures will become pale and discolored by 3 days. This progresses to total necrosis over 5 to 10 days. Wound dehiscence is inevitable; evisceration is common. The majority of these patients are ventilator dependent, and treatment of the abdominal wound with a binder alone is unsatisfactory in terms of being able to wean the patient from the ventilator. Consequently, some type of wound closure is required to facilitate ventilatory weaning. This almost always requires excision of the fascia and placement of a prosthetic mesh material, as the viscera are usually still edematous. This frustrating sequence of events can be circumvented by packing the abdomen open in patients who have prolonged hypotension requiring massive transfusions and distended, swollen viscera at the time of closure (Fig. 6). This technique is simple and successful if specific guidelines are followed. 6 Number 2 nylon sutures on a large retention suture needle are passed 4 cm from the skin border through skin, subcutaneous tissue, and fascia. Ideally, these sutures are passed extraperitoneally (Fig. 7A). The sutures are placed at 2-cm intervals. The exposed viscera are then covered with a porous material such as rayon gauze to facilitate the movement of serous fluid out of the peritoneal cavity and into the wound dressing. This gauze also protects the viscera from the overlying coarse fluff gauze. The rayon cloth, which can be purchased from the local department store, is
I
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
725
Figure 6. Standard closure of an abdominal incision may be impossible in the injured patient with marked hypotension, massive fluid and blood resuscitation due to dilated and edematous abdominal viscera, and loss of compliance of the abdominal wall.
cut in 2 feet by 2 feet sheets and kept sterile in the operating room. The rayon gauze is tucked underneath the wound margins to appr9ximately 4 cm beyond the border (Fig. 7B). Fluff gauze is placed over the rayon cloth and tucked under the wound margins. This entire pack of rayon cloth and fluffs is placed beneath the retention sutures. The retention sutures are then tied, thereby maintaining the viscera below the level of the peritoneum (Fig. 7C). Additional dressings are placed on top of the pack after the sutures are tied. These dressings help absorb excess abdominal fluid. The top gauze dressing is changed every 6 hours or as needed. The patient is taken back to the operating room at approximately 3 to 4 days, when the retention sutures and the abdominal pack are removed. Hopefully, the patient will have diuresed by this time, so that the abdominal wall is now compliant and the fascia can easily be approximated. If not, new retention sutures and a new abdominal pack are placed, so that by tightening the sutures, the width of the wound is decreased. Simultaneous re-exploration of intra-abdominal viscera for an intra-abdominal abscess or "checking" on the status of an anastomosis is meddlesome and discouraged. Manipulation of the intraperitoneal viscera leads to bacteremic showers and multiple organ failure from sepsis. The exposed portion of the bowel and other viscera is irrigated with saline just prior to placement of the new fascial sutures, which are then approximated. If the second abdominal pack is placed, the patient is again taken back to the operating room at 2 to 4 days, when the fascia can almost always be approximated without tension. The skin is always left open in these patients. There are some instances in which the patient will develop sepsis and multiple organ system failure in the presence of an open abdominal wound.
726
ANNA
M. LEDGERWOOD AND CHARLES E. LUCAS
Figure 7. A, Multiple retention sutures of 2~O nylon on a retention-suture needle placed 4 cm from the wound margin through skin, subcutaneous tissue, and fascia at 2-cm intervals. These sutures are placed ideally between the fascia and the peritoneum. B, A large sheet of rayon cloth is placed over the exposed viscera and tucked beneath the wound margins to protect the bowel from the retention sutures. Bulky gauze dressings are then placed beneath the retention sutures and above the rayon cloth to hold the cloth in place. , (Illustration continued on opposite page)
These patients do not have a spontaneous diuresis and, in fact, gain further fluid. In such instances, the patient's abdomen cannot be closed within 7 to 10 days. A granulating surface develops on the bowel by the tenth to the fourteenth days. It is tempting, at this time, to remove the retention sutures and the abdominal wall pack because the wound has a healthy and
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
727
Figure 7 (Continued). C, The retention sutures are then tied, holding the gauze pack beneath the level of the peritoneum and thus maintaining the viscera within the peritoneal cavity. The sutures are carefully tied to maintain the pack in place without strangulating the tissue. This allows for swelling to occur in the postoperative period and for fluid to exit the peritoneal cavity.
granulating appearance. Unfortunately, the granulating surface covering the exposed viscera will continue to expand and bulge from the wound over the next several days. An abdominal binder can help control this bulging, but it is not entirely successful. The layer of granulation tissue will become thinner as the bulging increases and, by 3 to 4 weeks following the initial operation, will develop small black blister elevations in the center of the granulating wound. These elevations feel like weak spots within a stiff fibrotic plate. Within a few days, these spots will perforate as tiny small or large bowels fistulas. 10 The abdominal wall, when left open without a pack support, tends to retract laterally, enlarging the wound dehiscence. This results in weak spots in the fibrotic plate, which gives way to these counteracting forces, causing bulging and erosion of the underling bowel. This complication is prevented by keeping retention sutures and the gauze pack in place until the granulating tissue is skin grafted and the skin graft has healed.
PERITONITIS AND ABSCESS FORMATION
The development of peritonitis and abdominal abscess following operation for abdominal trauma can almost always be related to technical difficulties, errors in judgement, or excessive soilage. Thus, these complications often can be prevented in the operating room at the initial operation. The young, healthy patient with severe abdominal injury can almost always
728
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
tolerate the initial insult of peritoneal spillage. However, the peritoneal cavity is less able to tolerate a second or third insult such as a leaking bowel anastomosis. Peritonitis is almost always due to a leaking bowel anastomosis or failure of a drain to evacuate pancreatic and biliary secretions. These complications generally do not present before the fifth postoperative day. They are usually detected by tachycardia, hyperventilation, a look of distress on the patient's face, fever, and leukocytosis. The abdomen usually becomes more distended and tender. These findings often are very difficult to appreciate in the critically ill patient with other organ injury, such as multiple extremity fractures and chest injury. Consequently, the authors are very conservative in the management of injuries to the hepatic, biliary, pancreatic, and intestinal systems. This is true not only for the stable patient but for also those patients who are critically ill and will require intensive care. There is a present trend to omit drainage for small liver injuries. The authors have seen significant bile drainage from stab wounds to the liver 1 cm in length. 8 It is impossible to predict which injuries of the liver will drain bile and which will not. Consequently, a drain in place for 2 to 3 days would indicate the presence of bile leakage and prevent bile peritonitis. Likewise, the pancreatic injury that will drain pancreatic fluid in the postoperative period is also totally unpredictable. Consequently, routine drainage of a pancreatic injury is advocated. Gastric, duodenal, and small bowel injuries are treated with closure or resection with an end-toend anastomosis. These anastomoses are hand sewn. The duodenum is decompressed with a tube duodenostomy for severe pancreaticoduodenal injuries treated with duodenal diverticulization. The management of colon injuries has vacillated from colostomy for all injuries to primary closure for most injuries. This recent swing to closure of colonic injuries will lead to an increased incidence of colonic perforations, peritonitis, abscess formation, and death. The criteria developed by Fabian and Stone for primary closure of a colon wound have worked well. 13 Deviation from these criteria is done at the patient's risk. Colostomy should routinely be performed for colon injuries in patients who are critically ill and who are going to be in the intensive care unit on a ventilator. It is extremely difficult to detect peritonitis in this patient. Intra-abdominal abscesses occur secondary to retained necrotic tissue or inadequately drained fluid collections. Consequently, drains that no longer function should be removed to prevent seeding of a blood or fluid collection with bacteria. Intra-abdominal abscesses are typically located in the upper quadrants after liver, spleen, or pancreatic injury. Pelvic abscesses are more commonly seen after rectal and sigmoid colon injuries or after pelviC fluid collections that have become contaminated. Evacuation of stagnant blood and thorough irrigation reduce this hazard. The stable patient with an evolving intra-abdominal abscess will develop fever and tachycardia with leukocytosis, lethargy, and anorexia near the seventh to tenth days following operation. Many of these patients are almost ready for discharge; in fact, some have been discharged home only to be readmitted with the above picture. These patients are best evaluated by exclusion of other sources for the fever, such as the wound, urinary tract, venous lines,
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
729
or the lungs. An abdominal CT scan will often localize the abscess. These abscesses frequently can be drained percutaneously by CT scan or ultrasound-guided aspiration and insertion of a drainage catheter without entering the peritoneal cavity. When this fails, open drainage is required. Ideally, these abscesses are drained without thorough exploration of the abdomen, lest the offending organisms be spread throughout the parietes. l The drained cavity is irrigated with saline or an antibiotic solution once the majority of the purulent drainage has stopped. Success in treatment of the stable patient by percutaneous drainage of an intra-abdominal abscess has led to enthusiasm for abdominal ultrasound and CT scan examinations in the critically ill patient with multiple system organ failure after trauma to detect a hidden intra-abdominal abscess. Because sepsis in most of these patients is due to pneumonitis or intravascular catheter devices, the roentgenographic exams of the abdomen are usually negative or nonconclusive.l1 This leads to the question of "blind" laparotomy, in which one looks for an intra-abdominal cause of the multiple organ failure from sepsis. When the clinical examination and the multitude of roentgenographic studies, including abdominal and pelvic CT scans, are negative, the authors decry this "blind" exploratory laparotomy as meddlesome, nonproductive, and harmful. The mortality rate is exceptionally high. 5 The abdominal CT scan is not useful in detecting abscesses during the first week after injury. The CT scan has a better yield in patients with cryptic fever and sepsis during the second or third week after injury. The use of CT -guided aspiration for abscess is not advised for therapy in all patients, but it may be helpful for diagnosis, if the collection is easily accessible, and for treatment, if the collection is small and can be aspirated completely.
FISTULAS AND STOMAS (DRAINS, TUBES, AND BAGS) Biliary fistulas following liver injury will almost always be present by the third postoperative day. The presence of bile in the drainage system. makes this diagnosis obvious. The biliary fistulas will likely cease draining spontaneously by the second or third week after injury.· If the drainage continues beyond the third week, an ERCP helps identify the site of extravasation and helps rule out distal obstruction, which would prevent spontaneous closure. The patient is allowed a regular diet despite the presence of the bile fistula. A pancreatic fistula is diagnosed by the high amylase in the drainage fluid. All pancreatic drains have fluid collected and analyzed on the second postoperative day. If the amylase is eler~!~cl. repeat analyses are done every other day until the drainage amylase" I§' the same as the serum amylase. By this time, the drainage often has ceased and the drain can be removed. 9 Pancreatic drains are usually left in place until the patient is able to tolerate a diet to be certain that there is no increase in drainage as the food stimulates the pancreatic enzymes. Small bowel fistulas are particularly difficult to treat because they usually present in an area not
730
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
amenable to "nagging." This leads to drainage on the skin and within the wound, causing excoriation of the skin. A sump drain in the base of the wound may be the best way to prevent drainage, causing excoriation of the skin. This sump is then covered with a gauze dressing and a plastic drape, which holds the dressing in place. Colostomy stomas matured in the operating room have immediate application of an appropriately fitting appliance. It is crucial that colostomies and ileostomies have the appiiance properly fitted to prevent spillage of bowel contents on the skin, which will certainly lead to excoriation and subsequent inability to fit other appliances. The stoma will often appear edematous and bulky in the early postoperative period in patients with severe injury and massive fluid therapy. These are the same patients that also have abdominal distension from ileus and bowel wall edema. The temptation to explore the stoma digitally in these patients in order to "get the patient to pass some gas" should be resisted. This exploration may cause full-thickness splitting of the stoma at the level of the fascia. This complication leads to spillage of bowel contents into the peritoneal cavity and into the stoma wound.
INTESTINAL OBSTRUCTION AND ACALCULOUS CHOLECYSTITIS Intestinal obstruction may be difficult to distinguish from postoperative adynamic ileus in the severely injured patient. As a general guideline, mechanical obstruction seldom presents during the first postoperative week, whereas adynamic ileus is less likely after the 14th day. Frequently, patients who have intestinal obstruction usually demonstrate temporary return of bowel function, with passage of flatus and stool.concomitant with a decrease in the abdominal girth. They often tolerate a liquid diet for 24 hours prior to the development of recurrent abdominal distension, vomiting, and obstipation. The development of these symptoms between the 8th and 14th postoperative days may be due to an unresolved ileus or a mechanical obstruction. Clinical correlation with abdominal exam and abdominal radiographs guides the appropriate decision regarding continued nasogastric suction versus operative intervention. Acalculous cholecystitis has occurred in injured patients, particularly critically ill patients who require ventilatory support and parenteral nutrition. This diagnosis is extremely difficult to make, but it should be considered when other causes of ongoing sepsis have been excluded. The presence of tachycardia, leukocytosis, right upper quadrant tenderness, and mild jaundice warrants evaluation for acute acalculous cholecystitis. Ultrasonography at the bedside may show a dilated gallbladder with a thick wall. The diagnosis is confirmed by isotopic scan, which shows a normal bile duct with lack of visualization of the gallbladder. 12 These patients should have laparotomy and cholecystectomy for acute acalculous cholecystitis.
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
731
REFERENCES 1. Altemeier W, Culbertson W, Fullen W, et al: Intra-abdominal abscesses. Am J Surg 125:70, 1973 2. Cerise E, Pierce W, Diamond D: Abdominal drains: Their role as a source of infection follOwing splenectomy. Ann Surg 171:764, 1970 3. Fullen W, Hunt J, Altemeier W: Prophylactic antibiotics in penetrating wounds of the abdomen. J Trauma 12:282, 1972 4. Harrigan C, Lucas C, Ledgerwood A: Serial changes in primary hemostasis after massive transfusion. Surgery 98:836, 1985 5. Hinsdale J, Jaffe B: Re-operation for intra-abdominal sepsis. Ann Surg 199:31, 1984 6. Ledgerwood A, Lucas C: Management of massive abdominal wall defects: Role of porcine skin grafts. J Trauma 16:85, 1976 7. Lucas C: Diagnosis and treatment of pancreatic am:\ duodenal injury. Surg Clin North Am 57:49, 1977 8. Lucas C, Walt A: Analysis ofrandomized biliary drainage for liver trauma in 189 patients. J Trauma 12:925, 1972 9. Martin F, Rossi R, Munson J, et al: Management of pancreatic fistulas. Arch Surg 124:571, 1989 10. Mastboom W, Kuypers H, Shoots F, et al: Small bowel perforation complicating the open treatment of generalized peritonitis. Arch Surg 124:689, 1989 11. Norwood S, Civetta J: Abdominal CT scanning in critically ill surgical patients. Ann Surg 202:166, 1985 12. Mirvis S, Vainwright J, Nelson A, et al: The diagnosis of acute acalculous cholecystitis: A comparison of sonography, SCintigraphy, and CT. AJR 47:1171, 1986 13. Stone H, Fabian T: Management of perforating colon trauma. Ann Surg 190:430, 1979 14. Villalba M, Lucas C, Ledgerwood A, et al: The etiology of post-traumatic empyema and the role of decortication. J Trauma 19:414, 1979
Address reprint requests to Anna M. Ledgerwood, MD Department of Surgery Wayne State University 4201 St. Antoine Detroit, MI 48201
Abdominal Trauma
+ .20
Postoperative Complications of Abdominal Trauma
Anna M. Ledgerwood, MD, * and Charles E. Lucas, MD*
Successful treatment of severe intra-abdominal injuries not only prolongs the useful lives of patients, but also provides a source of immense pleasure and satisfaction to the operating surgeon. Nothing disrupts this postoperative euphoria more than the evolution of a complication, especially when this complication is found, by subsequent study, to have been preventable. Trauma surgeons appear to surpass all others in attributing their complications to inadequate exploration, inappropriate decision making, technical misadventure, or poor perioperative care. The detrimental effects that hemorrhagic shock, massive blood transfusions, diffuse peritoneal soilage with feces and urine, and the unavoidably rough handling of tissue have on the normal physiologic defense mechanisms must be recognized. The ability of the body to handle such a massive peritoneal insult is astounding. One is not surprised that a second peritoneal insult from a leaking colon repair occurring during the inflammatory healing phase of the first insult is not well tolerated and may lead to multiple organ system failure and death. The objective is to identify those factors that can minimize the magnitude of the initial insult and decrease the likelihood of a second or third insult, which tips the scale against patient survival. The incidence of complications after abdominal trauma can be reduced by attention to protocol regarding resuscitation, priorities in diagnosis and treatment, antibiotic usage, and timely placement of tubes in body orifices. Efficient resuscitation with prompt operative intervention reduces the hemorrhagic shock insult and the extent of peritoneal spillage from hollow viscus perforation, thus minimizing the threat to the immunologic system. Proper preoperative assessment circumvents the need for intraoperative *Professor, Department of Surgery, Wayne State University, Detroit, Michigan This article was supported by the Interstitial Fluid Fund, Account No. 4-44966.
Surgical Clinics of North America-Vol. 70, No.3, June 1990
715
&
716
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
diagnostic studies performed with the abdomen open, which prolongs the anesthetic insult. For example, evaluation of hematuria during resuscitation avoids the need for intraoperative pyelography or aortography. The institution of preoperative antibiotic therapy in all patients with penetrating abdominal trauma and selected patients with blunt abdominal injury enhances the endogenous defense mechanism against infection. 3 More important than the specific antibiotic regimen is the recognition that postoperative infectious complications are reduced when antibiotics are initiated when the patient is first seen rather than after the abdomen is opened. Preoperative placement of chest tubes for suspected hemothorax reduces the chances for intraoperative pulmonary embarrassment. Preoperative nasogastric decompression decreases the likelihood for vomiting and aspiration. Any insult to one organ, especially the lungs, enhances the risk of complications elsewhere, including the abdomen. Intraoperative activities likely to reduce postoperative complications from abdominal trauma include care in the handling of body tissue, especially the intestines. When faced with the combined insult of active hemorrhage and overt leakage of bowel contents into the peritoneal cavity, control of bleeding carries the higher priority. Temporary control of bleeding by pack tamponade over an injured liver often allows for rapid closure of hollow viscus injuries, thereby decreasing the bacterial challenge. When this approach is feasible, a single-layer running closure of all hollow viscus perforations should be performed rapidly, after which the liver pack can be removed and definitive hepatic hemostasis achieved. Attention can then be directed back to the hollow viscus injuries for a second-layer or outer-layer closure. During the initial exploration, the small intestine often needs to be eviscerated and retracted to localize and control active hemorrhage. Once active life-threatening bleeding is contained and hollow viscus injuries are closed, the intestine should be returned to the abdomen with further retraction accomplished by deftly placed packs. This technical aid greatly reduces the extent of intraluminal and intramural bowel swelling and the severity of postoperative adynamic ileus. Postoperative complications in the patient with multiple injuries may be difficult to detect. Fever, leukocytosis, and abdominal distension may be from the laparotomy or from an extra-abdominal problem. Likewise, multiple organ system dysfunction may be a sign of an intra-abdominal and/ or extra-abdominal problem. Confirmation of an intra-abdominal complication often requires a second laparotomy. This decision may be difficult for the original surgeon, who may be confused by a combination of bias, ego conflict, frustration, and fatigue. A mature, well-rested surgeon who was not present at the original operation often can provide a nonbiased assessment regarding the need for reoperation. The original surgeon should participate at the second operation, if deemed advisable, and welcome the technical and moral support of the consultant surgeon.
POSTOPERATIVE HEMORRHAGE The most common complication occurring in the first 24 hours after operation is hemorrhage. Postoperative bleeding in a patient with minimal
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
717
injury and no shock will usually be within the peritoneal cavity and generally arises from the areas of previous dissection. This patient will have unexpected tachycardia, hypotension, abdominal distension, and anemia in the recovery room. Immediate reoperation identifies the source of bleeding, which usually is easily controlled. Intraperitoneal hemorrhage more commonly occurs in patients with at least moderate intraoperative transfusion requirements to correct unstable vital signs. Often these patients are marginally stable at the end of the initial operative procedure, so that unclamped but open blood vessels are not readily identified, clamped, and ligated. The hypotensive patient has what appears to be a relatively dry operative field near the end of an operative procedure because perfusion pressure is insufficient to cause frank bleeding through uncontrolled vessels. Consequently, such patients may be closed when there is minimal oozing, which becomes active arterial bleeding when the blood pressure is restored in the recovery room. The patient recovering from a moderate blood loss (2 to 10 transfusions intraoperatively) most likely has postoperative bleeding from incomplete surgical hemostasis. Assessment of platelet function (primary hemostasis) and the coagulation cascade leading to a fibrin clot (secondary hemostasis) helps identifY a coexistent nonsurgical bleeding problem. A platelet count above 75,000/mm 3 and a bleeding time under 9 minutes ensure adequate primary hemostasis, whereas a normal prothrombin time and partial thromboplastin time ensure adequate secondary hemostasis. 4 Furthermore, the patient should be warmed to normal body temperature. Hypothermic patients may have prolonged bleeding times and defective platelet aggregation, which correct with rewarming. When thrombocytopenia and a prolonged bleeding time are present, platelet infusion should be planned in conjunction with re-exploration. When the prothrombin time and partial thromboplastin time are prolonged, fresh frozen plasma infusion should be instituted. Most patients with postoperative bleeding have had severe hypovolemic shock, for which massive transfusions (10 to 30 units) are needed. Some patients are likely to have combined defects in both primary and secondary hemostasis, requiring both platelet and plasma therapy. Such patients may also have surgical bleeding, so that correction of the defects in hemostatic function is done in concert with re-exploration. A small number of severely injured patients will have bleeding that cannot be completely controlled at the initial operation such that packing is required. This is particularly true with massive liver injuries or retroperitoneal hemorrhage secondary to pelvic fracture. These patients almost invariably receive more than 25 transfusions during a prolonged operative procedure, leading to hypothermia below 34° C. When packing is necessary, the abdomen should be closed without drains or stomas. These patients almost always have impaired primary and secondary hemostasis with abnormal platelet aggregation, thrombocytopenia, and prolonged bleeding times, prothrombin times, and partial thromboplastin times. Such patients are taken to the intensive care unit, where they are rewarmed and their clotting deficiencies corrected. These patients have a planned second operation 24 to 48 hours later, when the packs are removed and definitive hemostasis is obtained.
"-SMII
718
M..
uk
ANNA
M.
LEDGERWOOD AND CHARLES
f
E.
LUCAS
MISSED ABDOMINAL INJURY Exploratory laparotomy for blunt and penetrating trauma requires discipline in a thorough exploration of the peritoneal cavity to detect all injuries. Once all identified injuries have been treated, a last look at sites and organs in a systematic manner removes the threat of missed injury. This last exploration is facilitated by a keen sense of paranoia and knowledge of the likely sites for missed injury. Such areas include the cardioesophageal junction, where injuries to the distal esophagus are not easily identified, particularly after penetrating wounds. Extra care is needed when examining the cardioesophageal junction and the posterior wall of the proximal stomach along the lesser curvature. This may require division of the gastroepiploic vessels along the greater curvature of the stomach, thereby permitting anterior rotation of the greater curve and visualization of the entire posterior gastric wall. Diaphragmatic rupture is commonly overlooked in patients with penetrating abdominal wounds. The origins of the diaphragm extend inferiorly to the second lumbar vertebra and are often not fully appreciated by the unwary surgeon who has just finished repairing an injured pancreas or colon in that region. Such patients may develop postoperative bleeding but are more likely to develop a hemothorax. Chest-tube thoracostomy will correct the hemothorax in many patients, but others with subdiaphragmatic infections will also develop empyema. 14 When these injuries are seen during the initial procedure, suture closure prevents, in most instances, the intrathoracic extension of infection. Missed diaphragmatic injury after laparotomy for blunt abdominal trauma is less common. The authors have had the opportunity to treat such a patient who had a laparotomy performed for a positive peritoneal lavage. The initial chest film was interpreted as being normal (Fig. 1). Laparotomy revealed a longitudinal laceration in the liver paralleling the falciform ligament. This was interpreted as the source of bleeding, which produced a positive peritoneal lavage. Hepatorrhaphy was achieved without incident, and the abdomen was closed. The postoperative course was complicated by fever and atelectasis (Fig. 2). A blunt rupture of the diaphragm was obvious by day 4 (Figs. 3 and 4), when the patient's respiratory distress worsened. Reoperation identified a 4-cm tear just to the left and anterior to the esophageal hiatus. Presumably, the left lobe of the liver hid this tear during the initial exploration. More likely, the operating surgeon relaxed after successfully controlling liver bleeding and neglected to perform the last preclosure exploration. Fortunately, the patient did well after reoperation and diaphragmatic repair. Missed injury to the extrahepatic biliary tree is avoided by careful inspection of the porta hepatis. One should look for hematoma or bile staining and perform a complete Kocher manuever to visualize the retroduodenal bile duct in patients with penetrating wounds in proximity or suspicious findings after blunt injury. Blunt bile duct injury usually occurs in the retroduodenal segment but may also occur in the right or left hepatic ducts. A missed injury may present with bile drainage through drains placed for other injuries. In the absence of drains, such patients are likely to develop the combination of fever, leukocytosis, bile-stained ascites, and
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
719
Figure 1. This patient had blunt trauma following an auto accident. This chest roentgenogram, which was obtained at admission, was interpreted as normal by the radiologist and the trauma surgeon.
jaundice. Endoscopic retrograde pancreatography (ERCP) identifies the anatomic defect and guides corrective operative intervention. Missed duodenal injury usually occurs in patients not explored, despite the clinical and roentgenographic findings indicative of duodenal rupture from blunt trauma. Penetrating duodenal perforations may be overlooked when they too are located on the posterior wall or along the mesenteric border adjacent to the pancreas. Complete examination of these areas is facilitated by inferior reflexion of the hepatic flexure of the right colon and full duodenal Kocherization. Postoperative findings likely to occur with unrecognized duodenal rupture include the typical findings of intra-abdominal sepsis, which rapidly progresses to systemic sepsis and threat of death. Diagnosis may be confirmed by upper endoscopy or an upper gastrointestinal contrast study with or without an abdominal computed tomographic (CT) scan. Once confirmed, the authors prefer closure of the duodenal perforation in conjunction with vagotomy, antrectomy, gastrojejunostomy,
720
ANNA
M. LEDGERWOOD AND CHARLES E. LUCAS
Figure 2. This chest roentgenogram was obtained on the second postoperative day for fever and suspected atelectasis. It was interpreted as shOwing gastric distention.
tube duodenostomy, and periduodenal drainage. 7 Other authors may advocate a less aggressive approach, depending upon the degree of injury and sepsis. Prevention of a missed pancreatic injury demands thorough lesser sac exploration and examination of the pancreas throughout its length. Injury to the main pancreatic duct is often difficult to detect. If the patient has blunt injury with transection of the pancreas overlying the vertebral column, duct injury is usually obvious. Penetrating wounds of the superior portion of the pancreas may involve the main pancreatic duct. If pancreatic juice flows from the wound, injury to the main duct is assumed and the pancreatic injury is treated accordingly. If no drainage ensues from the wound, simple drainage should be performed. Postoperative recognition of a missed pancreatic injury is made on the basis of peritoneal drainage containing a high amylase. When no drainage is used, the patient with a missed injury will develop the clinical and roentgenographic picture of lesser sac sepsis, similar to the clinical syndrome of an early pancreatic pseudocyst. Diagnosis
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
721
Figure 3. The chest roentgenogram was obtained on the fourth postoperative day for shortness of breath. This was interpreted by the radiologist as showing atelectasis and gastric distention. The trauma surgeon questioned the possibility of a diaphragmatic rupture.
of missed pancreatic injury is confirmed by ERCP, which also guides therapeutic intervention. When a missed pancreatic injury is combined with an associated hollow viscus perforation, the activation of proteolytic enzymes leads to overwhelming lesser sac inflammation, which demands early intervention. Missed injury to the colon or rectum may be devastating. A colon perforation most frequently will be missed because of inadequate mobilization and evaluation of the retroperitoneal colon. One cannot rule out, with certainty, retroperitoneal rectal injury from an intra-abdominal examination. Thus, preoperative assessment is crucial. The authors assume a rectal injury is present if there is blood on the examining finger, blood obtained with a Fleet enema prior to sigmoidoscopy, or blood seen on sigmoidoscopic examination when no other colon lesions are seen during laparotomy. Rectal injuries are treated with a proximal colostomy and drainage of the presacral space. Missed rectal injury leads to progressive pelvic sepsis, which in some patients extends retroperitoneally to the kidney, causing extensive sepsis, which is life threatening. Diagnosis is suspected clinically and by roentgenographic plain films or pelvic CT scan.
722
ANNA
M. LEDGERWOOD AND CHARLES E. LUCAS
Figure 4. An upper-gastrointestinal series was done that confirmed gastric herniation through a ruptured diaphragm.
Diagnosis is confirmed by endoscopy or contrast radiography. Endoscopy is preferred because the mixture of feces and barium in the retrorectal space acts synergistically to create overwhelming infection. Treatment consists of prompt proximal diversion and retrorectal drainage through the perineum. Ureteral injuries may be missed if there is not careful evaluation of the trajectory of missiles in the retroperitoneum. Likewise, injury to arteries and veins may be missed if the bullet track is not carefully evaluated as it enters the retroperitoneal area. Significant vascular injuries may occur with minor retroperitoneal hematomas. Thus, the path of the bullet should be exposed when the bullet has passed near the medially located major blood vessels. An arterial venous fistula of the iliac artery and vein may go undetected at the initial operation because the arterial blood leakage Hows directly into the vein without forming a perivascular hematoma. An example is a patient who had a very small hematoma in the area of the bullet where
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
723
it traversed the retroperitoneum and was not initially explored (Fig. 5). Postoperatively, the patient had a mechanical small bowel obstruction treated by lysis of adhesions. Again, no injury to the vessels was detected. The medical student caring for this patient noted a strange noise in the abdomen when listening for bowel sounds and called this to the attention of his more senior colleagues. This patient required a third operation for repair of his arteriovenous fistula.
WOUND COMPLICATIONS: INFECTION, NECROTIZING FASCIITIS, AND WOUND DEHISCENCE Wound infection following laparotomy for abdominal trauma is not uncommon. The combination of hemoperitoneum, devitalized tissue, and bowel perforation leads to significant bacterial contamination of the abdominal wound. Patients requiring laparotomy for blunt and penetrating trauma are treated preoperatively with broad-spectrum antibiotics. Such antibiotic
Figure 5. This patient sustained a gunshot wound of the abdomen that caused injuries to the small bowel 6 weeks previously. There was only a "small" retroperitoneal hematoma, and it was not explored. This aortogram was obtained because of an abdominal bruit heard on the fifth postoperative day, follOwing lysis of adhesions for a mechanical small bowel obstruction 6 weeks after the original injury. It demonstrates an arteriovenous fistula between the external iliac artery and vein. This injury was not detected at the original operation because the path of the bullet was not fully evaluated.
724
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
therapy will decrease the incidence of wound infection if the contamination is not excessive. Consequently, primary skin closure is avoided in patients who have colon injury with spillage (greater than 5 ml), moderate spillage from the small intestine or stomach (greater than 30 ml), or hypotension and massive transfusions (greater than 8 units). These patients are prone to develop wound infection, which can easily be prevented by simply leaving the skin open. Delayed primary closure can be performed by the fourth day if the patient is doing well and the wound looks good. Necrotizing fasciitis is the sequela to a wound infection that remains unrecognized and untreated. These patients often have had a fever on the third or fourth postoperative day. When the wound is finally opened on the fifth through the ninth postoperative days, there is foul-smelling drainage, with dissection of the bacteria along the fascia causing fascial necrosis as the virulence of the bacteria exceeds the defense of the hypaperfused fascia. This serious complication almost always leads to wound dehiscence and sometimes evisceration. These patients will almost always require a secondary procedure for debridement of the fascia and secondary wound closure. Necrotizing fasciitis may also occur when the skin is left open to heal by secondary intent. This problem occurs in patients with severe injury requiring multiple blood transfusions for prolonged hypotension and blood loss. Usually these patients have had very long operative procedures and generalized swelling that includes the abdominal viscera, especially the intestines. This generalized edema leads to loss of the abdominal wall compliance. The abdominal wound may be closed with "slight tension." When additional fluid and blood are required in the postoperative period and the abdomen swells further, the abdominal wall fascia is placed under undue tension as the swollen abdominal contents push against the wound. The fascia is always clearly visible because the skin has been left open. The portion of fascia included within the sutures will become pale and discolored by 3 days. This progresses to total necrosis over 5 to 10 days. Wound dehiscence is inevitable; evisceration is common. The majority of these patients are ventilator dependent, and treatment of the abdominal wound with a binder alone is unsatisfactory in terms of being able to wean the patient from the ventilator. Consequently, some type of wound closure is required to facilitate ventilatory weaning. This almost always requires excision of the fascia and placement of a prosthetic mesh material, as the viscera are usually still edematous. This frustrating sequence of events can be circumvented by packing the abdomen open in patients who have prolonged hypotension requiring massive transfusions and distended, swollen viscera at the time of closure (Fig. 6). This technique is simple and successful if specific guidelines are followed. 6 Number 2 nylon sutures on a large retention suture needle are passed 4 cm from the skin border through skin, subcutaneous tissue, and fascia. Ideally, these sutures are passed extraperitoneally (Fig. 7A). The sutures are placed at 2-cm intervals. The exposed viscera are then covered with a porous material such as rayon gauze to facilitate the movement of serous fluid out of the peritoneal cavity and into the wound dressing. This gauze also protects the viscera from the overlying coarse fluff gauze. The rayon cloth, which can be purchased from the local department store, is
I
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
725
Figure 6. Standard closure of an abdominal incision may be impossible in the injured patient with marked hypotension, massive fluid and blood resuscitation due to dilated and edematous abdominal viscera, and loss of compliance of the abdominal wall.
cut in 2 feet by 2 feet sheets and kept sterile in the operating room. The rayon gauze is tucked underneath the wound margins to appr9ximately 4 cm beyond the border (Fig. 7B). Fluff gauze is placed over the rayon cloth and tucked under the wound margins. This entire pack of rayon cloth and fluffs is placed beneath the retention sutures. The retention sutures are then tied, thereby maintaining the viscera below the level of the peritoneum (Fig. 7C). Additional dressings are placed on top of the pack after the sutures are tied. These dressings help absorb excess abdominal fluid. The top gauze dressing is changed every 6 hours or as needed. The patient is taken back to the operating room at approximately 3 to 4 days, when the retention sutures and the abdominal pack are removed. Hopefully, the patient will have diuresed by this time, so that the abdominal wall is now compliant and the fascia can easily be approximated. If not, new retention sutures and a new abdominal pack are placed, so that by tightening the sutures, the width of the wound is decreased. Simultaneous re-exploration of intra-abdominal viscera for an intra-abdominal abscess or "checking" on the status of an anastomosis is meddlesome and discouraged. Manipulation of the intraperitoneal viscera leads to bacteremic showers and multiple organ failure from sepsis. The exposed portion of the bowel and other viscera is irrigated with saline just prior to placement of the new fascial sutures, which are then approximated. If the second abdominal pack is placed, the patient is again taken back to the operating room at 2 to 4 days, when the fascia can almost always be approximated without tension. The skin is always left open in these patients. There are some instances in which the patient will develop sepsis and multiple organ system failure in the presence of an open abdominal wound.
726
ANNA
M. LEDGERWOOD AND CHARLES E. LUCAS
Figure 7. A, Multiple retention sutures of 2~O nylon on a retention-suture needle placed 4 cm from the wound margin through skin, subcutaneous tissue, and fascia at 2-cm intervals. These sutures are placed ideally between the fascia and the peritoneum. B, A large sheet of rayon cloth is placed over the exposed viscera and tucked beneath the wound margins to protect the bowel from the retention sutures. Bulky gauze dressings are then placed beneath the retention sutures and above the rayon cloth to hold the cloth in place. , (Illustration continued on opposite page)
These patients do not have a spontaneous diuresis and, in fact, gain further fluid. In such instances, the patient's abdomen cannot be closed within 7 to 10 days. A granulating surface develops on the bowel by the tenth to the fourteenth days. It is tempting, at this time, to remove the retention sutures and the abdominal wall pack because the wound has a healthy and
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
727
Figure 7 (Continued). C, The retention sutures are then tied, holding the gauze pack beneath the level of the peritoneum and thus maintaining the viscera within the peritoneal cavity. The sutures are carefully tied to maintain the pack in place without strangulating the tissue. This allows for swelling to occur in the postoperative period and for fluid to exit the peritoneal cavity.
granulating appearance. Unfortunately, the granulating surface covering the exposed viscera will continue to expand and bulge from the wound over the next several days. An abdominal binder can help control this bulging, but it is not entirely successful. The layer of granulation tissue will become thinner as the bulging increases and, by 3 to 4 weeks following the initial operation, will develop small black blister elevations in the center of the granulating wound. These elevations feel like weak spots within a stiff fibrotic plate. Within a few days, these spots will perforate as tiny small or large bowels fistulas. 10 The abdominal wall, when left open without a pack support, tends to retract laterally, enlarging the wound dehiscence. This results in weak spots in the fibrotic plate, which gives way to these counteracting forces, causing bulging and erosion of the underling bowel. This complication is prevented by keeping retention sutures and the gauze pack in place until the granulating tissue is skin grafted and the skin graft has healed.
PERITONITIS AND ABSCESS FORMATION
The development of peritonitis and abdominal abscess following operation for abdominal trauma can almost always be related to technical difficulties, errors in judgement, or excessive soilage. Thus, these complications often can be prevented in the operating room at the initial operation. The young, healthy patient with severe abdominal injury can almost always
728
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
tolerate the initial insult of peritoneal spillage. However, the peritoneal cavity is less able to tolerate a second or third insult such as a leaking bowel anastomosis. Peritonitis is almost always due to a leaking bowel anastomosis or failure of a drain to evacuate pancreatic and biliary secretions. These complications generally do not present before the fifth postoperative day. They are usually detected by tachycardia, hyperventilation, a look of distress on the patient's face, fever, and leukocytosis. The abdomen usually becomes more distended and tender. These findings often are very difficult to appreciate in the critically ill patient with other organ injury, such as multiple extremity fractures and chest injury. Consequently, the authors are very conservative in the management of injuries to the hepatic, biliary, pancreatic, and intestinal systems. This is true not only for the stable patient but for also those patients who are critically ill and will require intensive care. There is a present trend to omit drainage for small liver injuries. The authors have seen significant bile drainage from stab wounds to the liver 1 cm in length. 8 It is impossible to predict which injuries of the liver will drain bile and which will not. Consequently, a drain in place for 2 to 3 days would indicate the presence of bile leakage and prevent bile peritonitis. Likewise, the pancreatic injury that will drain pancreatic fluid in the postoperative period is also totally unpredictable. Consequently, routine drainage of a pancreatic injury is advocated. Gastric, duodenal, and small bowel injuries are treated with closure or resection with an end-toend anastomosis. These anastomoses are hand sewn. The duodenum is decompressed with a tube duodenostomy for severe pancreaticoduodenal injuries treated with duodenal diverticulization. The management of colon injuries has vacillated from colostomy for all injuries to primary closure for most injuries. This recent swing to closure of colonic injuries will lead to an increased incidence of colonic perforations, peritonitis, abscess formation, and death. The criteria developed by Fabian and Stone for primary closure of a colon wound have worked well. 13 Deviation from these criteria is done at the patient's risk. Colostomy should routinely be performed for colon injuries in patients who are critically ill and who are going to be in the intensive care unit on a ventilator. It is extremely difficult to detect peritonitis in this patient. Intra-abdominal abscesses occur secondary to retained necrotic tissue or inadequately drained fluid collections. Consequently, drains that no longer function should be removed to prevent seeding of a blood or fluid collection with bacteria. Intra-abdominal abscesses are typically located in the upper quadrants after liver, spleen, or pancreatic injury. Pelvic abscesses are more commonly seen after rectal and sigmoid colon injuries or after pelviC fluid collections that have become contaminated. Evacuation of stagnant blood and thorough irrigation reduce this hazard. The stable patient with an evolving intra-abdominal abscess will develop fever and tachycardia with leukocytosis, lethargy, and anorexia near the seventh to tenth days following operation. Many of these patients are almost ready for discharge; in fact, some have been discharged home only to be readmitted with the above picture. These patients are best evaluated by exclusion of other sources for the fever, such as the wound, urinary tract, venous lines,
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
729
or the lungs. An abdominal CT scan will often localize the abscess. These abscesses frequently can be drained percutaneously by CT scan or ultrasound-guided aspiration and insertion of a drainage catheter without entering the peritoneal cavity. When this fails, open drainage is required. Ideally, these abscesses are drained without thorough exploration of the abdomen, lest the offending organisms be spread throughout the parietes. l The drained cavity is irrigated with saline or an antibiotic solution once the majority of the purulent drainage has stopped. Success in treatment of the stable patient by percutaneous drainage of an intra-abdominal abscess has led to enthusiasm for abdominal ultrasound and CT scan examinations in the critically ill patient with multiple system organ failure after trauma to detect a hidden intra-abdominal abscess. Because sepsis in most of these patients is due to pneumonitis or intravascular catheter devices, the roentgenographic exams of the abdomen are usually negative or nonconclusive.l1 This leads to the question of "blind" laparotomy, in which one looks for an intra-abdominal cause of the multiple organ failure from sepsis. When the clinical examination and the multitude of roentgenographic studies, including abdominal and pelvic CT scans, are negative, the authors decry this "blind" exploratory laparotomy as meddlesome, nonproductive, and harmful. The mortality rate is exceptionally high. 5 The abdominal CT scan is not useful in detecting abscesses during the first week after injury. The CT scan has a better yield in patients with cryptic fever and sepsis during the second or third week after injury. The use of CT -guided aspiration for abscess is not advised for therapy in all patients, but it may be helpful for diagnosis, if the collection is easily accessible, and for treatment, if the collection is small and can be aspirated completely.
FISTULAS AND STOMAS (DRAINS, TUBES, AND BAGS) Biliary fistulas following liver injury will almost always be present by the third postoperative day. The presence of bile in the drainage system. makes this diagnosis obvious. The biliary fistulas will likely cease draining spontaneously by the second or third week after injury.· If the drainage continues beyond the third week, an ERCP helps identify the site of extravasation and helps rule out distal obstruction, which would prevent spontaneous closure. The patient is allowed a regular diet despite the presence of the bile fistula. A pancreatic fistula is diagnosed by the high amylase in the drainage fluid. All pancreatic drains have fluid collected and analyzed on the second postoperative day. If the amylase is eler~!~cl. repeat analyses are done every other day until the drainage amylase" I§' the same as the serum amylase. By this time, the drainage often has ceased and the drain can be removed. 9 Pancreatic drains are usually left in place until the patient is able to tolerate a diet to be certain that there is no increase in drainage as the food stimulates the pancreatic enzymes. Small bowel fistulas are particularly difficult to treat because they usually present in an area not
730
ANNA
M.
LEDGERWOOD AND CHARLES
E.
LUCAS
amenable to "nagging." This leads to drainage on the skin and within the wound, causing excoriation of the skin. A sump drain in the base of the wound may be the best way to prevent drainage, causing excoriation of the skin. This sump is then covered with a gauze dressing and a plastic drape, which holds the dressing in place. Colostomy stomas matured in the operating room have immediate application of an appropriately fitting appliance. It is crucial that colostomies and ileostomies have the appiiance properly fitted to prevent spillage of bowel contents on the skin, which will certainly lead to excoriation and subsequent inability to fit other appliances. The stoma will often appear edematous and bulky in the early postoperative period in patients with severe injury and massive fluid therapy. These are the same patients that also have abdominal distension from ileus and bowel wall edema. The temptation to explore the stoma digitally in these patients in order to "get the patient to pass some gas" should be resisted. This exploration may cause full-thickness splitting of the stoma at the level of the fascia. This complication leads to spillage of bowel contents into the peritoneal cavity and into the stoma wound.
INTESTINAL OBSTRUCTION AND ACALCULOUS CHOLECYSTITIS Intestinal obstruction may be difficult to distinguish from postoperative adynamic ileus in the severely injured patient. As a general guideline, mechanical obstruction seldom presents during the first postoperative week, whereas adynamic ileus is less likely after the 14th day. Frequently, patients who have intestinal obstruction usually demonstrate temporary return of bowel function, with passage of flatus and stool.concomitant with a decrease in the abdominal girth. They often tolerate a liquid diet for 24 hours prior to the development of recurrent abdominal distension, vomiting, and obstipation. The development of these symptoms between the 8th and 14th postoperative days may be due to an unresolved ileus or a mechanical obstruction. Clinical correlation with abdominal exam and abdominal radiographs guides the appropriate decision regarding continued nasogastric suction versus operative intervention. Acalculous cholecystitis has occurred in injured patients, particularly critically ill patients who require ventilatory support and parenteral nutrition. This diagnosis is extremely difficult to make, but it should be considered when other causes of ongoing sepsis have been excluded. The presence of tachycardia, leukocytosis, right upper quadrant tenderness, and mild jaundice warrants evaluation for acute acalculous cholecystitis. Ultrasonography at the bedside may show a dilated gallbladder with a thick wall. The diagnosis is confirmed by isotopic scan, which shows a normal bile duct with lack of visualization of the gallbladder. 12 These patients should have laparotomy and cholecystectomy for acute acalculous cholecystitis.
POSTOPERATIVE COMPLICATIONS AFTER ABDOMINAL TRAUMA
731
REFERENCES 1. Altemeier W, Culbertson W, Fullen W, et al: Intra-abdominal abscesses. Am J Surg 125:70, 1973 2. Cerise E, Pierce W, Diamond D: Abdominal drains: Their role as a source of infection follOwing splenectomy. Ann Surg 171:764, 1970 3. Fullen W, Hunt J, Altemeier W: Prophylactic antibiotics in penetrating wounds of the abdomen. J Trauma 12:282, 1972 4. Harrigan C, Lucas C, Ledgerwood A: Serial changes in primary hemostasis after massive transfusion. Surgery 98:836, 1985 5. Hinsdale J, Jaffe B: Re-operation for intra-abdominal sepsis. Ann Surg 199:31, 1984 6. Ledgerwood A, Lucas C: Management of massive abdominal wall defects: Role of porcine skin grafts. J Trauma 16:85, 1976 7. Lucas C: Diagnosis and treatment of pancreatic am:\ duodenal injury. Surg Clin North Am 57:49, 1977 8. Lucas C, Walt A: Analysis ofrandomized biliary drainage for liver trauma in 189 patients. J Trauma 12:925, 1972 9. Martin F, Rossi R, Munson J, et al: Management of pancreatic fistulas. Arch Surg 124:571, 1989 10. Mastboom W, Kuypers H, Shoots F, et al: Small bowel perforation complicating the open treatment of generalized peritonitis. Arch Surg 124:689, 1989 11. Norwood S, Civetta J: Abdominal CT scanning in critically ill surgical patients. Ann Surg 202:166, 1985 12. Mirvis S, Vainwright J, Nelson A, et al: The diagnosis of acute acalculous cholecystitis: A comparison of sonography, SCintigraphy, and CT. AJR 47:1171, 1986 13. Stone H, Fabian T: Management of perforating colon trauma. Ann Surg 190:430, 1979 14. Villalba M, Lucas C, Ledgerwood A, et al: The etiology of post-traumatic empyema and the role of decortication. J Trauma 19:414, 1979
Address reprint requests to Anna M. Ledgerwood, MD Department of Surgery Wayne State University 4201 St. Antoine Detroit, MI 48201
