Cases of pediatric intra-abdominal solid organ injury induced by blunt trauma experienced over a 15-year period at two centers in Japan

Introduction

Trauma is one of the leading causes of death and disability in children globally.1 Abdominal trauma occurs in approximately 25% of children with major trauma, and it is caused by blunt forces in most cases. Blunt abdominal trauma often leads to solid organ injury. The spleen is the most commonly injured organ, followed by the liver. Pancreatic injury is less common, but must not be overlooked due to its relatively high morbidity and mortality.2 Enhanced CT is the gold standard for identifying abdominal injuries. The sensitivity of ultrasonography (US) varies between 56% and 97% in detecting hemoperitoneum in cases with abdominal organ injury, and the utility of performing a routine focused assessment with sonography for trauma examination is limited in children.3 When pancreatic duct injury is suspected, endoscopic retrograde cholangiopancreatography can play an important role in obtaining an accurate diagnosis while also providing important information which can help in selecting optimal therapeutic options.4 Magnetic resonance cholangiopancreatography is also a non-invasive and useful modality to work up pancreatic injury if patients are stable.5 While it is widely accepted that most hepatic or splenic injuries can be managed non-operatively regardless of grade, management of pediatric pancreatic injury remains controversial. In any case, treatment at a specialized facility is almost always considered to be highly desirable.

Our prefecture (Kagoshima) has 605 islands and a very broad medical area extending 600 km from north to south and is characterized by a large number of inhabited islands. In our region, there are only two facilities capable of providing advanced treatment for pediatric trauma, such as treatment by pediatric surgeons, radiological intervention, and pediatric intensive care, and when specialized care is needed such patients must be transported by either airplane or helicopter.

In this study, we attempt to clarify the current status of care for severe pediatric trauma patients at two regional pediatric trauma center hospitals while also identifying the issues that need to be addressed in order to consolidate the care for these patients. The purpose of this study is to provide a reference material for improving the system of pediatric trauma care and to also consider some of the common problems when compared with other regions.

Methods

This is a retrospective study at two pediatric trauma centers in the southern Kyushu area of Japan. Blunt intra-abdominal solid organ injuries (liver, spleen, pancreas, or kidney) from 2007 to 2021 were included in this study. We excluded any patients who had a traumatic brain injury, or who were brought in while undergoing cardiopulmonary resuscitation and expired within 24 hours. The diagnosis was confirmed by imaging studies including enhanced CT and/or US in all patients. The medical charts were reviewed to collect data on age at diagnosis, sex, type of blunt trauma, injured organ, American Association for the Surgery of Trauma injury score,6 imaging findings, type of intervention, length of hospital stay, and late complications.

Results

Discussion

This study focused on pediatric trauma outcomes and retrospectively reviewed the treatment of these patients at two institutions. The major findings of this study are as follows: (1) regarding the clinical outcomes, conservative treatment was chosen in most cases and surgery was performed in only 12.8% of the cases; (2) pediatric patients with blunt trauma had favorable outcomes at two pediatric trauma centers covering a large medical area, including remote islands; and (3) increased ISS might be a significant factor associated with the perceived need for operative treatment.

The operative rate was 12.8% (8.0% of patients with liver injury and 37.5% of patients with pancreatic injury) in our study. Ozturk et al9 reported 205 pediatric blunt abdominal solid organ injury cases, of whom 35 (17%) patients were treated operatively. Spijkerman et al10 also reported 121 pediatric blunt abdominal injury cases, of whom 18 (14.9%) were treated operatively. In this report, 5 out of 43 (11.6%) patients with liver injury and 3 out of 7 (42.6%) patients with pancreatic injury underwent surgery. Our result does not seem to be so different from these results. Non-operative management (NOM) is considered the standard for blunt liver and splenic injury according to a retrospective study. Holmes et al showed an NOM failure rate of 3% for isolated liver injuries and 4% for isolated spleen injuries.11 None of our cases required surgery on the spleen, and conservative treatment, including embolization, is considered very effective. Despite a significant number of publications on this topic, the management of pancreatic injury remains controversial. Most patients with grade I and II pancreatic injuries can be managed non-operatively. However, as for grade III, laparoscopic resection has been reported to be effective in some studies.2 Additionally, the NOM failure rate is as high as 26% for pancreatic injuries, and especially high in patients with ductal injury.12 In this study, all grade I and II pancreatic injuries were treated non-operatively, while all grade III pancreatic injurieswere initially treated non-operatively, three of which eventually required surgery. These results might support the idea that conservative treatment is the mainstay of treatment for pediatric abdominal blunt trauma, but the requirement for surgery should be determined carefully.

There are several scoring systems for trauma severity classification even in children, but the ISS is often used since it is known to correlate well with the mortality of patients.8 The PTS is a scoring system that has been developed to classify the severity of pediatric trauma at the initial stage of treatment and is based on six factors: weight, respiratory status, contraction, blood pressure, consciousness, open wound, and fracture.7 Tepas et al13 found that the PTS value at admission was significantly related to the ISS value at discharge or death. Because it is pointed out that when PTS is used for triage, severe cases with a low PTS can be preferentially transferred to a higher trauma center, and medical facilities and other medical resources can be used more efficiently. While ISS is calculated based on anatomical severity, RTS and PTS concentrate more on physiological severity. In our study, RTS and PTS were not correlated with surgery, and only ISS was well correlated. This can be explained by the fact that three out of five surgical cases were patients with pancreatic injury whose vital signs were relatively stable at admission. On the other hand, PTS was correlated well with the length of intensive care unit stay in multiple trauma cases. These results may suggest that early transfer to a pediatric trauma center should be considered if pediatric abdominal trauma patients show either high ISS or low PTS at local hospitals.

Another problem is that of transfers. Our region has many remote islands, and direct transfer to two facilities is sometimes very difficult; we had 12 patients who were seen for more than 10 hours at a local clinic, all of whom were then transferred to a nearby hospital, in some cases for inpatient care, and only thereafter were they referred to our center. Available evidence shows no difference in mortality between transferred patients and those who received direct hospitalization. However, most studies exclude patients who died in outlying island hospitals, and therefore the association between transfer and mortality rates may remain unclear.14 Prospective studies, such as the use of population-based trauma registries, are needed to determine whether the process of interhospital transfer to higher tertiary care compared with direct admission to a trauma center adversely affects the clinical outcomes of trauma patients. For this purpose, it is necessary to develop population-based trauma registries in our region. Also, this study revealed that both trauma centers in our region have neither institutional nor shared guidelines for pediatric abdominal trauma. It is imperative to create our regional pediatric abdominal trauma guidelines considering geographical features. Such new guidelines will facilitate transfers from remote islands and lead to better clinical outcomes of pediatric trauma patients in our region.