INTRODUCTION
The therapeutic approach for colon and mesocolon injuries have changed continuously with the evolution of management strategies for trauma patients. However, there is ongoing debate regarding the therapeutic approach for blunt trauma. In general, immediate laparotomy can be considered in hemodynamically unstable patients with positive findings on extended focused assessment with sonography for trauma (eFAST) [
1]. However, in the case of hemodynamically stable patients, an additional evaluation is required [
2]. Surgical treatment is often required if prominent mesenteric extravasation, free fluid, bowel infarction, and/or colon wall perforation are observed on computed tomography (CT) [
2]. Except for the above cases, nonoperative management is more often used and may be appropriate [
3]. However, there are no clear guidelines for other colon and mesocolon injuries caused by blunt trauma. The blunt trauma causes serosal tears and devascularization of the colon without any findings that requires immediate treatment during initial evaluation, and it can eventually progress to bowel infarction or perforation [
4]. Therefore, surgical intervention is considered necessary when hypoenhancement of the bowel wall is observed. However, immediate intervention in hemodynamically stable patients without prominent perforation or necrosis remains questionable [
5].
In this study, we present several cases of nonoperative management of colon and mesocolon injuries caused by blunt trauma. The study was exempted from review by the Institutional Review Board of Chonnam National University Hospital due to minimal risk to subjects (No. CNUH-EXP-2021-284). Written informed consents were obtained from the patients.
DISCUSSION
The most common mechanism of injury in Korea is blunt injury (90.8%), as well as slip and fall down injuries (31.1%), vehicle associated accident (26.2%), and others [
6]. Blunt abdominal trauma can cause intraabdominal organ injury. The intestines are the third most commonly injured organs in blunt trauma [
7]. Small bowel injury accounts for 5% to 15% and colon injury accounts for 1% to 5% of blunt trauma cases [
7,
8]. In blunt trauma, patients with unstable vital signs and positive eFAST signs commonly require immediate intervention [
1]. CT evaluation can be done in patients with stable vital signs. In colon and mesocolon injuries, specific findings on physical examination or CT, such as extraluminal fluid collection, discontinuity of the bowel wall, pneumoperitoneum, or bowel infarction, are indications for immediate intervention [
9]. However, decision-making is often challenging in patients with colon and mesocolon injuries as there is no clear indications for surgical treatment [
4,
5].
There is currently no clear treatment guideline for the intestinal and mesenteric injury. For hollow viscus organ injury, there is a risk of increased morbidity and mortality when operation is delayed. Considering this, exploratory laparotomy had been performed in all cases of intestinal and mesenteric injury. However, there were many cases that surgery was not necessary in the end, and the incidence was up to 44% for intestinal lesions and up to 31% for mesenteric lesions [
3]. As a result, nonoperative management is being used more frequently and may be appropriate for hemodynamically stable patients without perforation or peritonitis [
3]. Treatment trend is changing. In this case report, it is meaningful to introduce cases that nonoperative management could be performed even for colon ischemia and large hematoma of mesocolon on CT.
In the case of acute bowel ischemia with submucosal edema and a shaggy contour rather than bowel infarction, as our cases, nonoperative management can be performed if the mesenteric vessels are maintained [
10]. However, as described above, bowel infarction is an immediate indication for laparotomy. Aggravation of pain and distension of abdomen or positive signs of peritonitis such as muscle guarding or rebound tenderness could indicate a worrisome situation such as progression to bowel infarction or perforation. In addition, vital signs and results of laboratory investigations are crucial and further evaluation options should be considered. The presence of devascularization and hematoma may lead to infarction and perforation; therefore, the therapeutic approach is decided based on the mechanism of injury, vital signs, symptoms, physical exam, laboratory investigations, and radiological investigations of the patient. In addition, the treatment plan can be changed according to the change of the patient's condition. The outcomes of the aforementioned cases suggest that nonoperative management could be a therapeutic option in patients with colon ischemia and mesocolon injuries with close monitoring. Moreover, this approach can be considered in cases of splenic flexure which is known as the watershed area and susceptible to ischemia, as reported in one of the aforementioned patients.
The nonoperative management of solid organ in trauma patient is a continuing trend [
11]. Treatment for intestinal and mesenteric injury is also shifting towards nonoperative management unless there is an immediate indication for laparotomy [
3]. By considering nonoperative management, nontherapeutic laparotomy can be reduced, and it can reduce the patient's pain and cost due to unnecessary laparotomy, as well as reduce morbidity such as mechanical ileus, hernia, and infection [
12].
However, in the event of worsening of the patient's vital signs or abdominal pain or an increase in the white blood cell count, additional investigations should be considered immediately [
13,
14]. In particular, additional evaluation should be considered in unconscious patients in case of any change in vital signs [
15]. It is important to consider the benefits of nonoperative management to the patient and the delay in surgical intervention that could increase the rates of morbidity and mortality [
4,
5].
Moreover, the long-term outcomes of patients who undergo nonoperative treatment should be evaluated. Intraabdominal abscess is one of the complications of nonoperative management of blunt trauma. Although many posttraumatic hematomas resolve on their own, percutaneous approaches may be useful for therapeutic and diagnostic purposes [
11].
In conclusion, nonoperative management can be considered as a therapeutic option for mesocolon and colon injuries caused by blunt trauma of selected cases, despite the presence of large hematoma and ischemia, if there are no clear indications for immediate intervention.