The accuracy of the scanner in exploring abdominal trauma in stable patients has been very well established [4]. However, in recent years, many series have raised the question of its necessity, especially in the pediatric population. Several authors have tried to limit the indications to certain critical situations [5–9]. Halaweich et al [10] have indeed noticed a decrease in compliance with guidelines for the use of computed tomography in abdominal trauma in children. The reasons are many. After a literature review, we identified relevant reasons which support us in our protocol excluding computed tomography.
CT and carcinogenic risk
In a cohort of 680,000 patients who underwent computed tomography, Mathews et al [11] found an increase in the overall cancer incidence of 27% among exposed subjects with a higher risk in toddlers. This risk was directly related to exposure and depending on the computed tomography site, abdominopelvic and thoracic computed tomography scans had the highest relative risks, 1.61 and 1.162, respectively. The risk after abdomino-pelvic scanner was much higher for certain types of cancer, in particular leukemia (OR: 3.42) and myeloodysplasias (OR: 2.17 to 4.84). There was also a significant increase in the rate of soft tissue, brain and all other solid cancers apart from melanoma and thyroid cancer. More specifically, Pearce et al [12] have shown that performing a computed tomography scan in childhood could triple the risk of leukemia when administered with a dose of 50 mGy and brain cancer if administration of 60 mGy. Within 10 years of the first scan, one case of leukemia and one case of brain tumor per 10,000 scans is estimated to occur in patients under 10 years of age [11]. Many other publications alert pediatric practitioners to the carcinogenic risks associated with the use of the scanner in childhood. And even if one might believe that the absolute risk is low and that it is possible to reduce the doses (the risk is not zero even at low doses) or that the clinical benefits should prevail, the conclusion is the same. All the authors recommend alternative solutions which do not involve ionizing radiation [13–17]. This is all the more valid in Africa, which contains 80% of the world's children and where cancer care is still a dilemma [18–20].
False negatives and false positives of CT
While the computed tomography scan allows rapid detection of hepatic and splenic lesions, a large proportion of pancreatic lesions go undetected as well as some lesions of the digestive tract whose presentation may be delayed [21–23]. In fact, the way in which computed tomography is performed has a lot of influence on the results. Sedation is necessary in children [21] but the safety of pediatric anesthesia is not yet effective in our skies and represents an additional cost for parents [24].
Besides, there are many trap images (electrode artifacts, various resuscitation equipment) that are sources of false positives. Edwards et al [25] found 2.5% false positives for abdominal computed tomography scan with a direct consequence of an increase in the length of hospital stay. Injecting the contrast products increases the sensitivity of the computed tomography scan but is not without side effects including allergic reactions, although these are mostly minimal. Their overall incidence reported in the literature is 4.3% [26, 27].
CT and prognosis
Almost all lesions will benefit from exclusive medical treatment which will be started upon admission for all patients [1]. For the rest, even if the ultrasound cannot be very precise on the diagnosis, hemodynamic instability will lead to surgery. Moreover, authors have already noted that, injected or not, the interpretation of abdomino-pelvic, computed tomography scans usually do not lead to a change in the therapeutic attitude [28]. Given the nil mortality in our series, we can conclude that not performing computed tomography seems to have no influence on the prognosis.
CT and cost
The relatively high cost of the scanner in a context where health insurance is a luxury, led us to establish this protocol by completely excluding the scanner, the price of which can cover hospital costs in the majority of cases. In fact, the patients remained hospitalized for a dozen days on average with hospital costs amounting to approximately 100 dollars or 2/3 of the cost of computed tomography. In addition, it has recently been proven that even in large trauma centers, 50% of computed tomography scans performed are negative [29], which would constitute a huge loss for our African population where funding for care is problematic. In the sub-region, computed tomography is rarely used in the assessment of abdominal trauma as it is not often available in many centers. When available, the long lead time for lack of financial means inevitably leads to a delay in any surgical intervention [20].
Benefits of abdominal ultrasound
It has the advantage of being able to be carried out in a few minutes in the breakout room or in the patient's bed. It was made systematic at the patient's bed on admission as was the case in our series. Indeed, it is easily renewable and non-irradiating. The results of ultrasound, potentiated by the experience of the operator, are often superior to those obtained in adults due to the thinness of the adipose membrane and the small size of the abdominal cavity in children [30–32].
Ultrasound is an excellent method of monitoring trauma to conservatively treated solid organs [21, 33]. Our 13 patients who had undergone non-operative treatment were monitored by ultrasound until they were discharged from the hospital. Ultrasound exploration is often limited by the inability to mobilize a polytrauma patient. Carrying out this bedside ultrasound helped circumvent this limiting factor in our establishment. The presence of gas linked to the existence of a reflex ileus or subcutaneous emphysema is also a brake. These reservations being made, ultrasound remains an irreplaceable tool in emergency settings, especially when performed by an experienced radiologist 30–32].
Better than conventional ultrasound, several authors have proven the effectiveness of ultrasound after injection of contrast agent comparable to computed tomography in the evaluation of traumatic visceral lesions in children [29, 34–36]. In our country, no contrast agent was used because it would be restrictive in our context with potential side effects. However, it would be a promising method [29] and a good possibility in countries with limited resources since it has the merit of sparing the child radiation, thereby reducing the risk of radiation-induced cancers.
Finally, it should be mindful that certain situations such as high kinetic traumas and polytrauma can justify a CT scan if possible.