Blunt bowel and mesenteric injuries detected on CT scan: who is really eligible for surgery?

A Retrospective Cohort Study on the Clinical Characteristics of Patients with Surgical Blunt Bowel and/or Mesenteric Injuries among Motorcyclists and Car Occupants

(1) Background: Surgical blunt bowel and/or mesenteric injuries (BBMIs) are rare but challenging for trauma surgeons. Surgical BBMI is associated with specific injury mechanisms, such as direct compression by the handlebar in motorcycle accidents or rapid acceleration and deceleration of the impact forces associated with seatbelt injuries in motor vehicle collisions. However, the discussions on the implications of BBMI and the mechanisms of road traffic accidents remain scarce. This retrospective study assessed the clinical and injury characteristics of surgically proven BBMI among motorcyclists and car occupants based on trauma-registered data obtained from a level I trauma center in Taiwan. (2) Methods: Medical data of 72 motorcyclists and 38 car occupants who had surgical BBMI between January 2009 and December 2020 were reviewed. Patient characteristics, injuries, and outcomes in both groups were compared and analyzed. (3) Results: Motorcyclists with surgical BBMI had a significantly higher Injury Severity Score (median [Q1–Q3], 18 (9–27) vs. 16 (9–18), p = 0.044) and lower Glasgow Coma Scale score (15 (11–15) vs. 15 (15–15), p = 0.034]) than car occupants. Motorcyclists with surgical BBMI had a higher incidence of pelvic fractures (18.1% vs. 2.6%, p = 0.032) and upper limb fractures (23.6% vs. 7.9%, p = 0.042) and a significantly higher rate of chest tube insertion than car occupants (29.2% vs. 10.5%, p = 0.027). However, there were no significant differences in the outcomes of morbidity and mortality between motorcyclists and car occupants with surgical BBMI. (4) Conclusions: This study demonstrated there were no significant differences in outcomes between motorcyclists and car occupants with surgical BBMI. However, motorcyclists with surgical BBMI were injured more severely, along with injuries to the head/neck and extremities, than car occupants.

Diagnostic Accuracy of Computed Tomography for the Prediction of the Need for Laparotomy for Traumatic Hollow Viscus Injury: Systematic Review and Meta-Analysis

BACKGROUND

Traumatic hollow viscus injury (THVI) is one of the most difficult challenges in the trauma setting. Computed tomography (CT) is the most common modality used to diagnose THVI; however, various performance outcomes of CT have been reported. We conducted a systematic review and meta-analysis to analyze how precise and reliable CT is as a tool for the assessment of THVI.

METHOD

A systematic review and meta-analysis were conducted on studies on the use of CT to diagnose THVI. Publications were retrieved by performing structured searches in databases, review articles and major textbooks. For the statistical analysis, summary receiver operating characteristic (SROC) curves were constructed using hierarchical models.

RESULTS

Sixteen studies enrolling 12,514 patients were eligible for the final analysis. The summary sensitivity and specificity of CT for the diagnosis of THVI were 0.678 (95% CI: 0.501-0.809) and 0.969 (95% CI: 0.920-0.989), respectively. The summary false positive rate was 0.031 (95% CI 0.011-0.071).

CONCLUSION

In this meta-analysis, we found that CT had indeterminate sensitivity and excellent specificity for the diagnosis of THVI.

The Current Diagnostic Accuracy on Free Peritoneal Fluid in Computed Tomography to Determinate the Necessity of Surgery in Blunt Bowel and Mesenteric Trauma-Systemic Review and Meta-Analysis

Traumatic bowel mesenteric injury (TBMI) is a challenge in trauma care. The presence of free peritoneal fluid (FF) in computed tomography (CT) was considered the indication for surgical intervention. However, conservative treatment should be applied for minor injuries. We conduct a systematic review to analyze how reliable the FF is to assess the TBMI. Publications were retrieved by structured searching among databases, review articles and major textbooks. For statistical analysis, summary receiver operating characteristic curves (SROCs) were computed using hierarchical models. Fourteen studies enrolling 4336 patients were eligible for final qualitative analysis. The SROC line was created by a hierarchical summary receiver operating characteristic model. The summary sensitivity of FF to predict surgical TBMI was 0.793 (95% CI: 0.635-0.894), and the summary specificity of FF to predict surgical TBMI was 0.733 (95% CI: 0.468-0.896). The diagnostic odds ratio was 10.531 (95% CI: 5.556-19.961). This study represents the most robust evidence (level 3a) to date that FF is not the absolute but an acceptable indicator for surgically important TBMI. However, there is still a need for randomized controlled trials to confirm.

Morbid Obesity's Silver Lining: An Armor for Hollow Viscus in Blunt Abdominal Trauma

BACKGROUND

Morbid obesity is usually accompanied by both subcutaneous and visceral fat accumulation. Fat can mimic an air bag, absorbing the force of a collision. We hypothesized that morbid obesity is mechanically protective for hollow viscus organs in blunt abdominal trauma (BAT).

METHODS

The National Trauma Data Bank (NTDB) was queried for BAT patients from 2013 to 2015. We looked at the rate of gastrointestinal (GI) tract injuries in all BAT patients with different BMIs. A subset analysis of BAT patients with operative GI tract injuries was performed to evaluate the need for abdominal operation. Multivariate analyses were carried out to identify factors independently associated with increased GI tract injuries and associated abdominal operations.

RESULTS

A total of 100,459 BAT patients were evaluated in the NTDB. Patients with GI tract injury had a lower proportion of morbidly obese patients [body weight index (BMI) ≥ 40 kg/m2)] (3.7% vs. 4.2%, p = 0.015) and instead had more underweight patients (BMI < 18.5) (5.9% vs. 5.0%, p < 0.001). The risk of GI tract injury decreased 11.6% independently in morbidly obese patients and increased 15.7% in underweight patients. Of the patients with GI tract injuries (N = 11,467), patients who needed a GI operation had a significantly lower proportion of morbidly obese patients (3.2% vs. 5.3%, p < 0.001). The risk of abdominal operation for GI tract injury decreased 57.3% independently in morbidly obese patients. Compared with underweight patients, morbidly obese patients had significantly less GI tract injury (6.0% vs. 13.3%, p < 0.001) and associated abdominal operation rates (65.2% vs. 73.3%, p < 0.001).

CONCLUSION

Obesity is protective in BAT. This translates into lower rates of GI tract injury and operation in morbidly obese patients. In contrast, underweight patients appear to suffer a higher rate of GI tract injury and associated GI operations.

Value of early repeated abdominal CT in selective non-operative management for blunt bowel and mesenteric injury

OBJECTIVES

To evaluate the performance of an early repeated computed tomography (rCT) in initially non-operated patients with blunt bowel and mesenteric injuries (BBMI).

METHODS

This was a monocentric retrospective observational study from 2009 to 2017 of patients with a BBMI on initial CT (iCT). Patients initially non-operated on were scheduled for a rCT within 48 h. Initial CT and rCT diagnostic performance were compared based on a surgical injury prediction score previously described. For statistical analysis, we used the chi-square analyses for paired data (McNemar test).

RESULTS

Eighty-four patients (1.9% of trauma) had suspected BBMI on iCT. Among these patients, 22 (26.2%) were initially operated on, 18 (21.4%) were later operated on, and 44 (52.4%) were not operated on. The therapeutic laparotomy rate was 85%. Thirty-four patients initially non-operated on had a rCT. The absolute value of the CT scan score increased for 15 patients (44.1%). The early rCT diagnostic performance, compared with iCT, showed an increase in sensitivity (from 63.6 to 91.7%), in negative predictive value (from 77.4 to 94.7%), and in AUC (from 0.77 to 0.94).

CONCLUSION

In initially non-operated patients with BBMI lesions, the performance of an early rCT improved the sensitivity of lesion detection requiring surgical repair and the security of patient selection for non-operative treatment.

KEY POINTS

• Selective non-operative treatment for hemodynamically stable patients with blunt bowel and/or mesenteric injuries on CT is developing but remains controversial. • An early repeated CT improved the sensitivity of lesion detection requiring surgical repair and the security of patient selection for conservative treatment.

Effectiveness of computed tomography scanning to detect blunt bowel and mesenteric injuries requiring surgical intervention: A systematic literature review

BACKGROUND

Computed tomography (CT) diagnostic accuracy for blunt bowel and mesenteric injuries (BBMI) is controversial.

DATA SOURCES

A literature review to compute aggregate CT performance and individual CT sign sensitivity, specificity, and positive predictive value (PPV) for operative BBMI.

CONCLUSIONS

Sensitivity, specificity, and PPV were: overall CT performance 85.3%, 96.1%, 51.4%; abnormal wall enhancement 30.1%, 95.7%, 64.0%; bowel wall discontinuity 22.3%, 99.0%, 87.9%; bowel wall hematoma 22.5%, 100%, 19.5%; bowel wall thickening 35.2%, 96.5%, 32.1%; free air 32.0%, 98.7%, 57.1%; free fluid 65.6%, 85.0%, 25.5%; mesenteric air 27.6%, 99.1%, 85.3%; mesenteric extravasation 22.9%, 99.6%, 73.9%; mesenteric hematoma/fluid 33.9%, 98.7%, 52.8%; mesenteric stranding/streaking 34.3%, 91.8%, 31.6%; mesenteric vessel beading 32.1%, 97.2%, 60.4%; mesenteric vessel termination 31.6%, 97.2%, 63.5%; oral contrast extravasation 10.0%, 100%, 100%; retroperitoneal air 9.4%, 94.9%, 55.6%; and retroperitoneal fluid 44.2%, 49.4%, 38.5%. Sensitivity, specificity, and PPV vary substantially among known signs. Other clinical factors are necessary for comprehensive BBMI identification.

Hollow viscus injury due to blunt trauma: A review

Blunt abdominal trauma results in injury to the bowel and mesenteries in 3-5% of cases. The injuries are polymorphic including hematoma, seromuscular tear, perforation, and ischemia. They preferentially involve the small bowel and may result in bleeding and/or peritonitis. An urgent laparotomy is necessary if there is evidence of active bleeding or peritonitis at the initial examination, but these situations are uncommon. The main diagnostic challenge is to promptly and correctly identify lesions that require surgical repair. Diagnostic delay exceeding eight hours before surgical repair is associated with increased morbidity and probably with mortality. Because of this risk, the traditional therapeutic approach has been to operate on all patients with suspected bowel or mesenteric injury. However, this approach leads to a high rate of non-therapeutic laparotomy. A new approach of non-operative management (NOM) may be applicable to hemodynamically stable patients with no signs of perforation or peritonitis, and is being increasingly employed. This attitude has been described in several recent studies, and can be applied to nearly 40% of patients. However, there is no consensual agreement on which criteria or combination of clinical and radiological signs can insure the safety of NOM. When NOM is decided upon at the outset, very close monitoring is mandatory with repeated clinical examinations and interval computerized tomography (CT). Larger multicenter studies are needed to better define the selection criteria and modalities for NOM.