Clinical features and outcomes of blunt splenic injury in children: A retrospective study in a single institution in China.

Although the spleen is the most commonly injured intra-abdominal organ after blunt trauma, there are limited data available in China. The objectives of this study were to investigate the clinical features and determine the risk factors for operative management (OM) in children with blunt splenic injury (BSI).A review of the medical records of children diagnosed with BSI between January 2010 and September 2016 at West China Hospital of Sichuan University was performed.A total of 101 patients diagnosed with BSI were recruited, including 76 patients transferred from other hospitals. The male-to-female ratio was 2.06:1, with a mean age of 7.8 years old. The most common injury season was summer and the most common injury mechanism was road traffic accidents. Sixty-eight patients suffered multiple injuries. Thirty-four patients received blood transfusions. Two patients died from multiple organ failure or hemorrhagic shock. Significant differences were observed in the injury season, injury mechanism, injury date, and hemoglobin levels between the isolated injury group and the multiple injuries group. The overall operative rate was 29.7%. Multivariate regression analysis revealed that age, blood transfusion, and grade of injury were independent risk factors for OM.Our study provided evidence that the management of pediatric BSI was variable. The operative rate in pediatric BSI may be higher in certain patient groups. Although nonoperative management is one of the standard treatment options, our data suggest that OM is an appropriate way to treat patients who are hemodynamically unstable.

Introduction

Child injuries are a major global public health problem because hundreds of thousands of children die from injuries every year.[ More than 12,000 children aged 19 or younger are killed by injuries each year in United States,[ and 95,000 children are hospitalized in Australia because of injuries every year.[ The child injury death rate, accounting for >95%, is much higher in low-income and middle-income countries.[ Although the rate of injury death is much lower in developed countries, there is no doubt that injury is the principal cause of death for children in both developing countries and developed countries.[ Approximately 10% to 15% of injured children suffer from abdominal injuries,[ which could lead to significant morbidity and mortality.[ Because of its anatomic location and highly vascularized parenchyma, the spleen is the most commonly affected organ in children who suffer blunt abdominal injury.[

The trend in the management of blunt splenic injury (BSI) has changed greatly over the past few decades.[ However, although Upadhyaya and Simpson[ first reported their successful nonoperative management (NOM) of pediatric BSI in 1968, splenectomy was still the predominant and standard treatment for pediatric BSI before the 1980s.[ The awareness of the importance of the immunological function of the spleen[ and the recognition of the risk of complications induced by splenectomy, especially overwhelming postsplenectomy infection (OPSI),[ promote alternatives to conservative treatment for the management of pediatric BSI. Compared with splenectomy, the benefits of conservative approaches also include fewer blood transfusions, shorter length of hospital stay (LOS), and lower hospital costs.[ The American Pediatric Surgical Association and the Eastern Association for the Surgery of Trauma established the evidence-based management guidelines for children with BSI in 2000 and 2003, respectively.[ Currently, the NOM is the standard approach for hemodynamically stable children with BSI.

Although the NOM is the recommended therapy for splenic injury with a success rate of >90%,[ different regimens still exist for the treatment of splenic injury. The factors influencing clinical management decisions vary and include surgeon practices, hospital types, and patients characteristics.[ Several studies have provided evidence that there is a higher operation rate in nonpediatric hospitals[ and nonpediatric trauma centers.[ Evidently, adult surgeons are more inclined to treat pediatric BSI with operative management (OM).[ In addition, patients’ factors, including age, injury type, injury mechanism, and blood transfusion, could have an important influence on clinical decision making for the treatment of pediatric BSI.[ The operation rate varies with differences in geographic area and changes among different levels of economic society. Unfortunately, there is limited data available on the management of pediatric BSI in China. A better understanding of the clinical features and epidemiological characteristics could contribute to the establishment of effective methods to prevent and treat pediatric splenic injuries.

The aim of this study was to investigate the clinical characteristics of pediatric BSI in a single institution in China. We presented the clinical features and identified the risk factors for operative interventions in pediatric BSI. We hypothesized that patients who were hemodynamically unstable and/or suffered multiple injuries had a higher probability of undergoing an operation.

Methods

This study was approved by the institutional review board of the West China Hospital of Sichuan University. We conducted a retrospective study of all the children younger than 18 years with a diagnosis of BSI from January 2010 to September 2016 in West China Hospital of Sichuan University. Written informed consent was obtained from all patients’ parents. Clinical information, including demographics, clinical presentations, laboratory results, imaging findings, treatment strategies, and outcomes, were obtained. To present the patients’ characteristics and properly determine the risk factors for OM, we divided the patients into 4 groups based on the treatment strategy (OM and NOM) and injury types (isolated BSI and BSI with multiple injuries).

All data were analyzed by SPSS version 23.0 for Windows (SPSS Inc, Chicago, IL). Student t test was used to analyze the quantitative variables. Pearson chi-squared test and Fisher exact test were used for the analysis of categorical variables. Multivariate logistic regression analyses were performed to detect the independent risk factors for the operation in BSI with odds ratios (ORs) and 95% confidence intervals (CIs). P values less than .05 were considered statistically significant.

Results

As shown in Table 1, a total of 101 patients diagnosed with BSI were enrolled. There were 68 men and 33 women, with a male-to-female ratio of 2.06:1. Male patients were predominant in all age groups. The mean age at presentation of BSI was 7.8 years (range 0–17 years). Nearly half of the patients (44.6%) were younger than 6 years. With regard to the admission sources, 76 (75.2%) patients were transferred from other hospitals.

Table 1

Demographic characteristics and clinical features of patients with blunt splenic injury.

The most common injury season was summer, representing 39.6% of all BSIs. More than half of the patients (65.3%) suffered the injury on a weekday. BSIs most occurred between 12:00 and 17:00 O’ clock (41.6%). According to the American Association for the Surgery of Trauma, the mean grade of spleen injury was 3.3 with grade III injury (33.7%) the most common. The higher grade of spleen injury accounted for 43.6% including 29.7% for grade IV injury and 13.9% for grade V injury. In terms of the mechanism of injury, road traffic accidents (RTAs) accounted for 51.5% of cases. The majority of patients (67.3%) suffered coexisting injury/injuries. The most common associated injury was lung injury (26.7%), followed by brain injury (21.8%) and liver injury (21.8%). Eighty-five (84.2%) patients presented with complaints of abdominal pain.

Computed tomography was the first imaging modality in 87.1% cases. Of the 101 patients, 37 were transferred to intensive care unit (ICU). The mean ICU LOS and mean hospital LOS were 1.94 days (range 0–16 days) and 10.50 days (range 1–46 days), respectively. Thirty-four (33.7%) patients received red blood cell transfusion. Most patients (70.3%) were monitored conservatively, whereas 21.8% patients were treated with splenectomy alone. The remaining patients (7.9%) underwent splenorrhaphy. The majority of patients (98.0%) had a favorable outcome. Two (2.0%) patients died during hospitalization: one 4-year-old patient died from multiple organ failure and another 11-month-old patient died from hemorrhagic shock.

As shown in Table 2, there were no significant differences between the isolated injury group and the multiple injuries group in age, sex, and treatment regimens (P > .05). Similarly, no statistically significant differences were found in injury time, body temperature, and outcomes between the isolated injury group and multiple injuries group (P > .05). In contrast, significant differences were observed in the injury season, injury mechanism, injury date, and hemoglobin levels between the 2 groups (P < .05). The prevalence of BSI with multiple injuries varies in different seasons, with the highest prevalence (45.6%) in the summer. RTA (63.2%) was the main injury mechanism in the multiple injuries group, whereas a fall from nonheight (36.4%) was the main injury mechanism in the isolated injury group (P < .001). Compared with the isolated injury group, abdominal tenderness was less likely to occur in the multiple injuries group (P < .05). Obviously, patients with multiple injuries were more likely to receive blood transfusion than patients with isolated injury (41.2% vs 18.2%, P = .022). The average hospital and ICU stays in the multiple injuries group were much longer those that observed in the isolated injury group (P < .001).

Table 2

Comparison of children who suffered blunt splenic injury with or without multiple injuries.

As shown in Tables 3 and 4, univariate analysis was performed to analyze the differences between the OM group and NOM group. We found that older age, injury season (winter), lower body temperature, blood transfusion, grade of injury, longer ICU LOS, and longer hospital LOS were significant factors associated with OM (P < .05). Based on the statistically significant difference uncovered in univariate analysis, the results of multivariate regression analysis indicated that older age (OR = 5.581, 95% CI: 1.547–20.142, P = .009), blood transfusion (OR = 5.570, 95% CI: 1.577–19.675, P = .008), and grade of injury (OR = 9.220, 95% CI: 1.468–57.915, P = .018) were independent risk factors for OM. In contrast, injury season, lower body temperature, longer ICU LOS and longer hospital LOS failed to reach independent significance by multivariate analysis (Table 4).

Table 3

Comparison of children who suffered blunt splenic injury with or without operative management.

Table 4

Multivariable analysis on the factors influencing clinical decisions to perform operative management of blunt splenic injury.

Discussion

One purpose of this study was to determine the clinical features of pediatric BSI in our hospital, with the aim of improving our understanding of pediatric BSI and preventing mortality and morbidity in severe cases. The results from our study were comparable with previous data, demonstrating that men were more likely to suffer BSI than women.[ Reasons for this phenomenon may include that boys behave more impulsively and are exposed to more risks than girls. In addition, our data showed that abdominal pain was the most common symptom that patients presented. This finding was consistent with a previous study by Kristoffersen and Mooney,[ who reported that complaints of abdominal pain were fairly common among children with splenic injury.

Remarkably, studies investigating the injury mechanisms in pediatric BSI yielded different results. Several studies demonstrated that falls were the most common cause of BSI injury.[ However, in the present study, we found that RTA (51.5%) was the predominant cause of BSI. This finding was in accordance with the results from studies in which the most common mechanism of BSI was motor vehicle collision.[ In addition, patients with BSI caused by RTA were more likely to suffer multiple injuries. It is conceivable that they were more likely to receive operative treatments when compared to patients with BSI caused other injuries. The reason for this might be due to the great force of impact on the body when accidents occurred. In contrast, children who suffered lower levels of force, such as assault, were less likely to be associated with severe BSI. Correspondingly, they were less likely to be treated with an OM.

Our data demonstrated that BSI occurred most frequently between 12:00 and 17:00 O’clock, no matter what type of injury it was and which type of management patients received. We found that our patients were more likely to suffer multiple injuries in the summer. However, patients who sustained injury in the winter were more likely to receive operative intervention. These findings were interesting, but the reasons for these phenomena are unclear. In addition, due to the lack of relevant clinical records, no validated data on daily activities are currently available. Therefore, our study could not accurately determine the causes. Future studies are needed to explain these phenomena.

Our study revealed that nearly half of the patients were younger than 6 years. Patients aged 0 to 5 years were predominant in both the isolated injury group and multiple injuries group. In addition, our data indicated that older patients were more likely to undergo operative intervention than younger patients. These findings were in line with the results from previous reports.[ Plausible explanations for this phenomenon may include that the younger children can tolerate more higher-grade injuries with nonoperative treatment compared to old patients.[ Furthermore, younger children may suffer higher risks of serious infection after splenectomy,[ although it is a much debated issue in adult patients. Therefore, caution is usually exercised in younger children because of the risk of OPSI.

As described above, NOM was the first choice for pediatric surgeons to treat children with BSI. In the present study, the success rate of splenic preservation in patients who underwent NOM was 100%, which was consistent with previous studies that concluded that the success rate of splenic preservation has increased to >90%.[ However, the nonoperative rate of BSI in the present study was 70.3%, which was lower than the benchmark for NOM rate in several recent studies.[ We were curious about this finding. Currently, there is ongoing controversy regarding the primary independent determinant factor of the need for splenectomy in children with BSI.[ The primary indication for splenectomy in our hospital is hemodynamic instability in children with BSI. Other indications include the presence of multiple intra-abdominal injuries and ongoing transfusion requirements. The high rate of operation in our cases may reflect a referral bias. Our hospital is the largest and leading trauma center in West China. Children with severe splenic trauma may have been transferred to our department from other hospitals. In patients receiving OM, 70.0% of patients were transferred from other hospitals, indicating that transferred patients were more likely to undergo operations. Second, previous studies demonstrated that patients who suffered multiple injuries had a higher probability of receiving OM compared to patients with isolated injury.[ In keeping with these studies, the operation rate in our patients with multiple injuries was nearly 2 times higher than that in patients with isolated injuries, although the difference between the 2 groups was not statistically significant. Furthermore, 33.7% of our patients received blood transfusions. In this regard, a strong association between blood transfusion and OM was noted, further confirming the concept that hemodynamic instability was an important factor for OM in pediatric BSI.[

The limitations of this study include its retrospective nature and small sample size. We cannot rule out the possibility that seriously injured patients were more likely to be transferred to our hospital. In addition, the present study was conducted in a single institution. The results presented here may not be generalizable to the Chinese population. Future population-based multiple-center studies are needed to determine the precise characteristics of pediatric BSI in China.

Conclusion

In conclusion, our data emphasize that the operative rate in pediatric BSI may be higher in certain patient groups. Our data suggest that older age, blood transfusion, and grade of injury are independent risk factors for OM in pediatric BSI. Our research could contribute to a better understanding of BSI patients’ characteristics in China.

Consent

Written informed consent regarding the publication of this study and the accompanying images was provided by the patients’ parents. Copies of the signed informed consent forms are available for review by the Series Editor of Medicine.

Ethical approval

This study was approved by the Ethics Committee of the West China Hospital of Sichuan University. Written informed consents were obtained regarding the use of the images in accordance with the Declaration of Helsinki.