Pediatrics

Outcomes of basic versus advanced prehospital life support in severe pediatric trauma

a b s t r a c t

Objective: The role of basic life support (BLS) vs. Advanced life support in pediatric trauma is controversial. Although ALS is widely accepted as the gold standard, previous studies have found no advantage of ALS over BLS care in adult trauma. The objective of this study was to evaluate whether ALS transport confers a survival advan- tage over BLS among severely injured children.

Methods: A retrospective cohort study of data included in the Israeli National trauma registry from January 1, 2011, through December 31, 2020 was conducted. All the severely injured children (age < 18 years and injury severity score [ISS] >=16) were included. Patient survival by mode of transport was analyzed using logistic regression.

Results: Of 3167 patients included in the study, 65.1% were transported by ALS and 34.9% by BLS. Significantly more patients transported by ALS had ISS >=25 as well as Abnormal vital signs at admission. The ALS and BLS cohorts were comparable in age, gender, mechanism of injury, and prehospital time. Children transported by

ALS had higher in-hospital mortality (9.2% vs. 0.9%, p < 0.001). Following risk adjustment, patients transported by ALS teams were significantly more likely to die than patients transported by BLS (adjusted OR 2.27, 95% CI 1.05-5.41, p = 0.04). Patients with ISS >=50 had comparable mortality rates in both groups (45.9% vs. 55.6%,

p = 0.837) while patients with GCS <9 transported by ALS had higher mortality (25.9% vs. 11.5%, p = 0.019).

Admission to a level II trauma center vs. a level I hospital was also associated with increased mortality (adjusted OR 2.78 (95% CI 1.75-4.55, p < 0.001).

Conclusions: Among severely injured children, prehospital ALS care was not associated with lower mortality rates relative to BLS care. Because of potential confounding by severity in this retrospective analysis, further studies are warranted to validate these results.

(C) 2023

Abbreviations: TC, trauma center; BLS, basic life support; ALS, advanced life support; INTR, Israeli National Trauma Registry; ISS, Injury Severity Score; MVC, motor vehicle col- lision; ED, emergency department; HR, heart rate; SBP, systolic blood pressure; GCS, Glasgow Coma Scale; SI, Shock Index; AIS, Abbreviated Injury Score; EMS, emergency medical services; MDA, Magen David Adom; STROBE, Strengthening the Reporting of Observational studies in Epidemiology; OR, odds ratio; CI, confidence interval.

* Corresponding author.

E-mail address: [email protected] (D. Epstein).

1 Israel Trauma Group (ITG) includes: A. Acker, N. Aviran, H. Bahouth, A. Bar, A. Becker,

A. Braslavsky, D. Fadeev, A. L. Goldstein, I. Grevtsev, I. Jeroukhimov, A. Kedar, A. Korin, B. Levit, A. D. Schwarz, W. Shomar, D. Soffer, I. Schrier, M. Venturero, M. Weiss, O. Yaslowitz, I. Zoarets.

  1. Introduction

Trauma is the leading cause of death and disability among children [1]. Although injury prevention is the ultimate goal, well-structured trauma systems decrease morbidity and mortality after injury [2]. Prehospital care is a part of the “Chain of survival“, stretching from the site of injury to the trauma center (TC) where definitive care is provided [3]. Prehospital care is generally classified into basic life support (BLS) and Advanced Life Support levels. BLS-level care is usually pro- vided by emergency medical technicians and includes a limited set of interventions, such as external Hemorrhage control, oxygen

https://doi.org/10.1016/j.ajem.2022.12.045

0735-6757/(C) 2023

supplementation, bag-valve-mask ventilation, and spinal immobiliza- tion. ALS personnel, usually paramedics or physicians, receive additional training and are capable of performing more advanced procedures on scene and en route. These include advanced airway management, vascular access, chest decompression, and medication administration, among others.

ALS is widely accepted as the gold standard of prehospital trauma care. However, its efficacy, compared to BLS, has been questioned. Although randomized trials comparing ALS with BLS are unlikely, multiple retrospective studies have found no advantage of ALS over BLS care in regard to mortality and neurological outcomes in both blunt and penetrating adult trauma patients [3-5]. Extrapolating findings from these studies to the pediatric population is difficult: the epidemiology of pediatric trauma differs from adults, with a higher pro- portion of falls and head trauma and a lower prevalence of hemorrhagic shock and chest injuries [6-8]. In addition, most prehospital clinicians do not routinely take care of severely injured children, and there is a gap in the quality of care provided to pediatric patients as compared to adults [9].

The objective of this study was to evaluate the relationship between the clinical outcomes of pediatric Trauma victims and the level of prehospital care. Using the Israeli National Trauma Registry (INTR), we evaluated whether ALS is associated with better survival among severely injured pediatric patients when compared to BLS prehospital care.

  1. Materials and methods
    1. Data collection and definitions

The study population consisted of all the severely injured pediatric patients defined as patients younger than 18 years with an Injury Sever- ity Score (ISS) >=16 admitted to one of the hospitals included in the INTR

between January 2011 and December 2020. This ISS threshold was cho-

sen to select patients with severe injury in keeping with most trauma literature. This is also the threshold generally used to classify patients requiring TC care or full trauma team activation [10]. Moreover, because very few children with an ISS < 16 would likely die during admission, the threshold helped prevent dilution of the main effect in which we were interested [11].

We excluded patients transported by private or police vehicles, as well as those who were dead on arrival. Patients were also excluded if they had incomplete records for the primary outcome of in-hospital mortality or were transferred to or from another hospital.

We extracted the following data from the INTR:

      1. Demographics: age, gender
      2. type of injury: penetrating, blunt
      3. Mechanism of injury: motor vehicle collision , fall, other (burns, violence, and other unintentional injuries)
      4. Prehospital airway interventions: Bag-mask ventilation and endotracheal intubation
      5. Time from ambulance dispatch to hospital arrival (prehospital time)
      6. Vital signs at admission to the emergency department (ED): oxygen saturation, heart rate (HR), systolic blood pressure (SBP), and Glasgow Coma Scale (GCS). The pediatric GCS was utilized for pre-verbal children [12]. In addition, the Shock Index , defined as HR divided by SBP, was calculated for each patient. A high SI

was defined as >1.2 for children <=6 years, >1 for children 7-12 years, and > 0.9 for children >12 years [13,14].

      1. Receiving hospital level: level ? or level II TC
      2. Length of hospital stay
      3. ISS, using standard categories (1-15, 16-24, 25-49, and 50-75) [15].
      4. Abbreviated Injury Score for head, thorax, abdomen, and extremities, with AIS scores >=4 considered severe

The primary outcome of this study was survival to hospital discharge, defined as the patient leaving the hospital alive or being transferred to a long-term care or rehabilitation facility.

    1. Study design and setting

This was a retrospective cohort study based on the INTR. The registry includes detailed information regarding trauma patients hospitalized in all six level ? TC and 15 level ?? centers, which together treat >95% of trauma patients in Israel. All the TCs in Israel are mixed, treating both adult and pediatric patients. The database does not include patients who died at the scene, en route, or who were discharged home follow- ing treatment in the ED. The data included in the registry is recorded by trained trauma registrars at each TC, under the supervision of a trauma director and trauma coordinator. Electronic files are transferred regularly to the National Center for Trauma and Emergency Medicine Research where additional quality control is carried out [16,17].

Emergency medical services (EMS) in Israel are provided mainly by the Magen David Adom (MDA) organization augmented by volunteer- based first-responder programs, medical corps teams, and some private carriers. MDA operates 169 stations with a fleet of over 1000 ambu- lances and two helicopters. MDA, as well as other EMS providers, run

two-tier EMS responses: BLS and ALS. The BLS ambulances (~65% of ambulances) are staffed mainly by emergency medical technicians

and occasionally by paramedics. These vehicles are equipped to provide basic treatment (external hemorrhage control, oxygen supplementa- tion, bag-valve-mask ventilation, spinal immobilization, etc.). Most of the ALS teams are staffed by paramedics who are capable of providing advanced interventions including advanced airway management, intra- venous and intraosseous access, medications administration (analgesic and Sedative agents, Tranexamic acid, intravenous fluids, etc.), and chest decompression. Some ALS teams also had physicians as part of their staff (specifically, some MDA teams between January 2011 and December 2015; some military teams; and some private ambulances). Local policy dictates that the assignment of ALS or BLS ambulances is based on availability and proximity. In addition to the closest team, an ALS ambulance is dispatched based on certain criteria conveyed during the request for help. Some of the criteria that dictate ALS activation in- clude high-risk mechanism of injury (e.g. high-speed crash; vehicle entrapment; ejection from vehicle; pedestrian/bicyclist struck by vehi- cle; fall from high), high-risk anatomical injury (e.g. penetrating injury to head, neck, torso or extremities proximal to elbow/knee; amputation proximal to wrist/ankle; suspected spinal cord injury), Altered level of consciousness, respiratory distress/arrest, seizures, and severe blood loss. In Israel, the median response time (time from ambulance dispatch to arrival to the scene) is eight minutes and in 95% of cases, this time is

<20 min. The median hospital transport time is 15 min and 95% of the patients arrive at a hospital within 35 min [18]. The BLS teams do not delay patient care or transport while waiting for ALS personnel, and transfer from BLS to ALS (or vice versa) en route is discouraged except during prolonged transportation. As the INTR does not have an indicator for patients who are transferred from BLS to ALS units (or vice versa) en route, in this study, the team that provided care at the time of hospital arrival was credited with the transportation.

The Israeli EMS guidelines dictate that the ambulance services should triage suspected major trauma patients directly to level 1 TCs when transport time is expected to be <40 min. “Suspected major trauma” is defined by local EMS as patients suffering from an injury in- volving three or more of the following anatomic regions: head, face, chest, abdomen, pelvis, or long bones; or the presence of a high-risk mechanism of injury [e.g. high-speed crash; vehicle entrapment; ejec- tion from vehicle; pedestrian/bicyclist struck by vehicle; or fall from high]. Otherwise, patients are either evacuated to the closest hospital for stabilization with subsequent transfer to a level 1 TC as appropriate or transferred directly to a level I TC by helicopter. Patients suspected to have suffered from isolated severe traumatic brain injury (defined as

any penetrating head injury, suspected Skull fracture, or GCS < 15) are transferred to the closest hospital with neurosurgical capabilities. If the EMS team deems a patient too unstable for a longer transport to a level I TC, he is transported to the nearest hospital for initial stabiliza- tion. BLS teams and paramedic-staffed ALS teams are not allowed to pronounce death or discontinue resuscitation in pediatric patients.

The study was approved by the Institutional Review Board of Sheba Medical Center (approval number 5138-18 SMC). Individual patient consent was waived because all data in the INTR are anonymous. The Strengthening the Reporting of Observational studies in Epidemiology (STROBE) statement was used to guide reporting of this research [19].

    1. Statistical analysis

Patients’ characteristics were summarized with descriptive statistics. Categorical variables were reported as frequencies and per- centages and continuous variables as medians with interquartile ranges (IQR). Baseline characteristics and unadjusted mortality rates between patients transported by BLS and those transported by ALS teams were compared using ?2 and Mann-Whitney U test.

Because patients transported by ALS are presumably at higher risk of

death than those transported by BLS, we used logistic regression modeling to determine the odds of death among ALS relative to BLS- transported trauma victims, controlling for potential confounders: age, gender, type and mechanism of injury, receiving hospital level, GCS at ED arrival, and ISS were included in the model.

Previous studies have found that GCS is highly predictive of mortal- ity in Pediatric trauma patients and performs comparably to more comprehensive physiological scores such as the Pediatric Trauma Score and the Revised Trauma Score [20-22]. This may be explained by the fact that traumatic brain injury and anoxia are the main causes of death among injured children, while death from hemorrhage is rare [23]. We used GCS at ED admission as it is influenced not only by the se- verity of the injury but also by the level of prehospital care.

The ISS is an anatomic score and independent predictor of survival following severe pediatric trauma [11,24]. Some previous works suggest that ISS should be included as a categorical rather than a continuous var- iable for statistical or analytical purposes, as single ISS values have little prognostic meaning [15,25]. However, ISS values of BLS and ALS groups may distribute differently across the range of each ISS category. Given the above, we performed the logistic modeling twice, once with ISS as a continuous variable and once as a categorical variable. We decided a priori that the categorical analysis would be the one on which we would draw our conclusions, but that if there were a substantial discrepancy between the results of the two analyses, we would urge caution in their interpretation.

Finally, given the long study period and changes in the trauma treatment guidelines, as well as ambulance staffing in MDA, we also in- vestigated the effect of the time trends (i.e., the year of admission) on the results of the analysis.

The association between independent variables and the predefined outcome was quantified using odds ratios (OR) and 95% confidence in- tervals (CI). Missing data were handled by listwise deletion. The model’s discriminative ability was measured via a concordance index (c-index). We considered a p-value of 0.05 statistically significant. Data analysis was conducted with SAS software, version 9.4 (SAS Institute, Cary, NC, USA).

  1. Results

Of the 110,227 children included in the INTR from January 1, 2011, to December 31, 2020, a total of 3167 patients were included in the study after applying the inclusion and exclusion criteria (Fig. 1). Of the in- cluded patients 2062 (65.1%) were transported by ALS teams. Two hundred six (10.0%) of the patients treated by ALS teams were transported by helicopter EMS. A level I TC was the primary destination

Image of Fig. 1

Fig. 1. Study flow chart.

INTR- Israeli National Trauma Registry; EMS- Emergency medical services; ISS- Injury Severity Score.

of the EMS teams in 2393 (75.6%) cases. More patients treated by ALS teams were transported to level I TCs (80.5% vs. 66.3%, p < 0.001).

The most common mechanisms of injury were MVC (53.5%) and falls (28.8%). Only 213 children (6.7%) suffered from Penetrating injuries, 80.0% of them caused by stabbing or gunshot wounds, and 83.1% of them were transported by ALS teams.

Significantly more patients transported by ALS sustained critical injuries, defined by ISS 25-49 and >= 50 (46.5% vs. 23.0% and 4.8% vs. 0.8%, p < 0.001, respectively). More patients transported by ALS teams suffered from severe injuries (AIS >= 4) involving more than one body re- gion (11.7% vs. 1.9%, p < 0.001). In the BLS group, 51.2% were diagnosed

with an isolated severe head injury compared to 43.8% in the ALS group (p < 0.001). At admission to the ED, more patients treated by the ALS teams had GCS < 9 (33.8% vs. 5.5%, p < 0.001), oxygen saturation

<90% (4.1% vs. 1.5%, p < 0.001), and high shock index (35.8% vs. 26.6%, p < 0.001). The ALS and BLS cohorts were comparable in age, gender, mechanism of injury, and prehospital time. Full demographic and injury information is provided in Table 1.

prehospital airway interventions were more common in patients treated by ALS responders: 138 patients (6.7%) were ventilated by a bag valve mask in the ALS group compared to 9 (0.8%) in the BLS group (p < 0.001). Endotracheal intubation was performed by ALS teams in 483 (23.4%) patients. Intravenous fluids were given to 779 (37.8%) patients in the ALS group vs. 58 (5.3%) in the BLS group (p < 0.001). Splinting of suspected fractures was also performed more frequently by ALS teams, with 1277 (62.2%) ALS patients vs. 343 (31.0%) BLS patients splinted in the field (p < 0.001).

Children transported by ALS had higher overall mortality than those

transported by BLS (9.2% vs. 0.9%, p < 0.001) with an unadjusted relative risk of mortality of 10.18 (95% CI 9.94-15.25, p < 0.001). Among

Table 1

Demographic and injury characteristics of severely injured children by type of emergency medical services transport (n = 3167)

Advanced life support (n = 2062) Basic life support (n = 1105) p-value

Age (years)

0.83

Median (IQR) 10 (4,15)

10 (5,15)

Male gender, n (%)

1511 (73.3%)

818 (74.0%)

0.68

Penetrating injury, n (%)

177 (8.6%)

36 (3.3%)

<0.001

Mechanism of injury

0.97

Fall, n (%)

549 (26.6%)

362 (32.7%)

Motor vehicle collision, n (%)

1102 (53.4%)

592 (53.6%)

Other?, n (%)

411 (20.2%)

151 (13.7%)

Time from dispatch to hospital arrival (min)

0.76

Median (IQR)

57 (42,75)

56 (42,79)

Unknown (%)

637 (30.9%)

296 (26.8%)

Receiving Level I trauma center, n (%)

1660 (80.5%)

733 (66.3%)

<0.001

Vital signs at emergency department admission

Glasgow Coma Scale, n (%)

3-8

698 (33.8%)

61 (5.5%)

9-14

350 (17.0%)

137 (12.4%)

<0.001

15

933 (45.3%)

886 (80.2%)

Unknown

81 (3.9%)

21 (1.9%)

Oxygen saturation < 90%, n (%)

85 (4.1%)

16 (1.5%)

<0.001

Unknown

172 (8.4%)

72 (6.5%)

High Shock Index, n (%)

739 (35.8%)

293 (26.6%)

<0.001

Unknown

104 (5.0%)

45 (4.1%)

Injury severity score, n (%) Median (IQR)

25 (18-30)

18 (16-24)

16-24

1005 (48.7%)

842 (76.2%)

<0.001

25-49

958 (46.5%)

254 (23.0%)

>=50

99 (4.8%)

9 (0.8%)

Injured body region, n (%)

<0.001

Isolated severe head injury (AIS >=4)

903 (43.8%)

566 (51.2%)

Isolated severe chest injury (AIS >=4)

281 (13.6%)

126 (11.4%)

Isolated severe abdomen injury (AIS >=4)

125 (6.1%)

121 (11.0%)

Isolated severe extremities injury (AIS >=4)

19 (1.0%)

5 (0.5%)

Isolated severe external injury (AIS >=4)

103 (5.0%)

37 (3.3%)

Multiple severe injuries

241 (11.7%)

21 (1.9%)

No regions with AIS 4+

390 (18.9%)

229 (20.7%)

Length of hospital stay (days)

<0.001

Median (IQR) 7.0 (4,15) 5.0 (3,8)

Total in-hospital mortality, n (%)

190 (9.2%)

10 (0.9%)

<0.001

Mortality in the ED

41 (2.0%)

3 (0.3%)

<0.001

AIS- Abbreviated Injury Scale.

Statistically significant p-values (p <= 0.05) are in bold and italicized.

* Other includes burns, violence, and other unintentional blunt or penetrating injuries.

patients with ISS of 25-49 the hospital mortality rate of those transported by ALS was 14.7% vs. 2.0% in the BLS group (p < 0.001). Patients with ISS >=50 had comparable mortality rates in both groups (45.9% vs. 55.6%, p = 0.84) (Fig. 2a). ALS patients with GCS <9 at admis- sion had a significantly higher mortality rate compared to those

transported by BLS with GCS <9 (25.9% vs. 11.5%, p = 0.019) (Fig. 2b). After adjustment for demographics, type and mechanism of injury, receiving hospital level, GCS, and ISS, patients transported by ALS teams were significantly more likely to die than patients transported by BLS (adjusted OR 2.27, 95% CI 1.05-5.41, p = 0.04). Other risk factors associated with increased mortality were older age, higher ISS, GCS 3-8 at admission to the ED, mechanism of injury, and admission to a level II hospital versus a level I TC. The complete results of the multivariate analysis are provided in Table 2. The model included 3065 patients (96.8%) and its c-index was 0.95 (95% CI 0.94-0.96, p < 0.001). When ISS was included in the model as a continuous (rather categorical) variable, transportation by ALS teams was still associated with increased mortality with an adjusted OR of 2.4 (95% CI 1.1-5.7, p = 0.03). The addition of the time trend did not significantly change the results of the analysis, as well. When the year of admission was incorporated into the model, transportation by the ALS team was associated with in- creased mortality with an adjusted OR of 2.32 (95% CI 1.02-5.64, p = 0.04). Other risk factors for increased mortality were also not affected

by these changes.

  1. Discussion

In this large-scale nationwide retrospective cohort study, we found that ALS transport and prehospital care do not improve outcomes of severely injured children, as compared with BLS. Although due to the retrospective nature of the study, there is a potential for residual and unmeasured confounding by severity, these findings are important as they identify an additional component of prehospital trauma care that may be associated with significant differences in mortality and may pro- vide an opportunity to improve the pediatric prehospital trauma care system.

Multiple studies demonstrated that among adult trauma patients prehospital ALS care is not associated with a significant survival advan- tage and may be associated with increased mortality [4,5,26]. Most of these studies were retrospective and observational. However, the Ontario Prehospital Advanced Life Support (OPALS) major trauma study was a before-after system-wide controlled clinical trial involving 17 cities in Ontario, Canada, that evaluated data of 2867 trauma patients before and after ALS program implementation [27]. The researchers found that the implementation of full ALS programs did not decrease mortality or morbidity for major trauma patients. Moreover, among pa- tients with GCS < 9, survival was lower during the ALS phase. Longer prehospital times and a higher number of prehospital procedures may account for these differences. Sampalis et al. found that for each

Image of Fig. 2

Fig. 2. The relationships between prehospital mode of transport, in-hospital mortality, in- jury severity score (a), and Glasgow Coma Scale at admission to the emergency depart- ment (b).

additional minute spent during prehospital care, the odds of dying in- creased by 5% [28]. Similar findings were demonstrated by Gauss et al [29]. In urban trauma systems, prehospital endotracheal intubation is associated with greater mortality when compared with bag-valve- mask ventilation en route [30]. Vascular access is established in the vast majority of ALS patients without any proven Survival benefit and intravenous infusion of crystalloids may have a harmful effect on bleed- ing patients [31,32]. prehospital administration of plasma was associated with reduced mortality among bleeding patients only when the transport time was longer than 20 min [33]. These findings were not confirmed in pediatric trauma patients among whom death from hemorrhage is uncommon [23].

Our knowledge regarding the relationship between the prehospital level of care and clinical outcomes of injured children is scant. Children comprise only 5-10% of total EMS patients and most EMS teams, treating mainly adult patients, have only limited experience in the clinical assessment and treatment of severely injured children [9,34]. In contrast to adult casualties, a recent study of 597 pediatric trauma pa- tients in Sweden found that longer transport time after major pediatric trauma was not associated with adverse outcomes [35]. However, in accordance with studies in adult patients, prehospital intubation was shown to have no benefit or harm during various resuscitative scenarios [36-38]. Not only was the benefit of this intervention not clearly shown, but this high-skill and high-risk procedure is often performed without a clear indication and carries a high rate of complications (10-39%) among children intubated by EMS [39,40]. Only a few studies evaluated the association between the level of prehospital care and clinical out- comes. Orr et al. found that pediatric specialized transport teams have

Table 2

Multiple variable logistic regression analysis for in-hospital mortality (n = 3065).

Parameter

Adjusted Odds Ratio for mortality (95% CI)

p-value

Age category (years)

0-4

Reference

5-9

0.33 (0.19-0.57)

<0.001

10-17

0.42 (0.27-0.65)

<0.001

Gender (female)

1.30 (0.87-1.93)

0.20

Type of injury

Blunt

Reference

Penetrating

1.69 (0.80-3.55)

0.17

Mechanism of injury Fall

Reference

Motor vehicle collision

1.78 (1.09-2.96)

0.02

Other?

2.49 (1.27-4.72)

0.007

Receiving hospital (Level I trauma center)

0.36 (0.23-0.57)

<0.001

Glasgow coma scale category

15

Reference

9-14

1.00 (0.14-4.46)

0.99

3-8

44.36 (20.39-116.88)

<0.001

Injury severity score category 16-24

Reference

25-49

9.55 (4.62-23.16)

<0.001

>=50

35.72 (15.43-94.23)

<0.001

Prehospital level of care

Basic Life Support

Reference

Advanced Life Support

2.27 (1.05-5.41)

0.04

CI- confidence interval.

The model included 3065 patients (96.8%) and its c-index was 0.95 (95% CI 0.94-0.96, p < 0.001).

Statistically significant p-values (p <= 0.05) are in bold and italicized.

* Other includes burns, violence, and other unintentional blunt or penetrating injuries.

better outcomes compared to nonspecialized teams. Interestingly, these teams performed fewer major interventions than nonspecialized teams [41]. Brown et al. found that scene transport by helicopter EMS was associated with improved odds of survival compared with ground EMS in pediatric trauma patients, despite longer prehospital times [42]. To the best of our knowledge, the only study that compared the outcomes of severely injured children treated by physician-staffed ALS versus BLS was conducted in Finland in 1994 and included 121 patients. The authors found an improved outcome for those treated by ALS teams [43]. Our findings are different. After adjusting for injury severity, the odds of death for ALS transports were 2.27 times that for BLS transports (95% CI 1.05-5.41), although the prehospital times did not differ signif- icantly between the groups. The differences were most prominent in patients with ISS of 25-49 (mortality rates of 2.0% vs. 14.7%, p < 0.001) and among those with GCS < 9 (11.5% vs. 25.9%, p = 0.02). We speculate that these differences may be related to the tendency to per- form advanced procedures, such as intravascular access establishment, endotracheal intubation, medication administration, and splinting of suspected fractures in these patients. We found that ALS may have a

small advantage for the most severely injured patients (ISS >= 50). How- ever, the differences did not reach statistical significance (45.9% vs. 55.6%, p = 0.84), possibly due to the small number of patients in this group (108 patients).

Among other variables independently associated with increased mortality in our cohort was treatment in level II TCs (OR 2.8) rather than in level I TCs. Studies in adult trauma patients were similar to this finding [44]. Previous studies also found that centralization of pediatric trauma patients in dedicated TCs is associated with better out- comes [45,46]. This survival advantage was not demonstrated for level I dual TCs (both general/pediatric) although severe pediatric trauma patients treated in higher volume adult centers had better outcomes than those treated in lower volume centers [47,48]. As all TCs in Israel are dual TCs, our findings support the claim that high-volume level I

TCs treating both children and adults may have an advantage over smaller TCs for the treatment of severely injured children.

Although our findings are based on a nationwide cohort, as Israel is a small urban country with relatively short evacuation times, they should be extrapolated with caution to Rural settings with prolonged evacuation times and to countries with mainly physician-staffed EMS. In addition, our cohort includes predominantly blunt trauma patients making our findings relevant mainly to this population. However, the prevalence of penetrating trauma among children is variable, ranging from 2% to 20%, in different countries [49,50]. Our study has some addi- tional limitations. First, patients’ assignment to the two transport groups was nonrandomized, and more severely injured patients were preferentially assigned to the ALS group. Although our mortality multi- variate model could efficiently distinguish between the positive and negative cases with a very high c-index (0.95, 95% CI 0.94-0.96), it was limited to the data available in the INTR. Potential confounding risk factors for mortality were not included in the risk-adjustment process. For example, although the prehospital times were not different for the ALS and BLS groups, they were not included in the model due to a large amount of missing data. Although the admission vital signs reflect the injury severity and the effect of prehospital care, the Prehospital vital signs could potentially enable more accurate adjustment of the model. However, these were not included in the analysis due to a large amount of missing data. The exact level of treatment (paramedic vs. physician) is also not included. An additional parameter not included in INTR is a transfer from BLS to ALS (or vice versa) en route. The INTR does not have an indicator for patients who are transferred from BLS to ALS units (or vice versa) en route. Although discouraged by the guidelines, these transfers may lead to additional bias. Furthermore, we expect that such transfers would prolong the evacuation time, and no such difference was observed between the groups. Second, our

study included only a small group of patients with an ISS >= 50, therefore our ability to offer a recommendation for that subset of patients is lim-

ited, though our data suggest that these extremely ill children may ben- efit from ALS response. Unfortunately, ISS is not a useful tool for field triage, as it cannot be calculated in prehospital settings. Third, as this study is based on the INTR, it includes only hospitalized patients; casu- alties who died at the scene or en route were not included (patients who were declared dead in the ED are included in the INTR). It should be noted that BLS teams and paramedic-staffed ALS teams are not allowed to pronounce death or discontinue resuscitation in pediatric patients. Therefore, we believe that the death of only a few children was declared on scene or en route by physician-staffed ALS teams. In addition, the registry does not include long-term outcomes following patient discharge.

  1. Conclusion

Among severely injured children (ISS >= 16), prehospital ALS care was not associated with lower mortality rates relative to BLS measures. Our findings suggest that rapid transport to definitive surgical care in

high-volume TCs with only BLS-level interventions may result in im- proved survival compared with more advanced prehospital care. How- ever, because of potential confounding by severity in this retrospective analysis, further studies are warranted to validate these results.

Funding

This research did not receive any specific grant from funding agen- cies in the public, commercial, or not-for-profit sectors.

DATA statement

The data that support the findings of this study are available from the corresponding author, upon reasonable request.

Source of support and sponsorship

None.

CRediT authorship contribution statement

Danny Epstein: Writing – original draft, Validation, Supervision, Project administration, Methodology, Investigation, Conceptualization. Sharon Goldman: Writing – review & editing, Methodology, Investiga- tion, Formal analysis, Data curation. Irina Radomislensky: Writing – review & editing, Visualization, Validation, Methodology, Investigation, Formal analysis, Data curation. Aeyal Raz: Writing – review & editing, Methodology, Investigation, Conceptualization. Ari M. Lipsky: Writing – review & editing, Methodology, Formal analysis, Conceptualization. Shaul Lin: Writing – review & editing, Supervision, Methodology, Inves- tigation, Conceptualization. Moran Bodas: Writing – review & editing, Writing – original draft, Supervision, Resources, Project administration, Methodology, Investigation, Data curation, Conceptualization.

Declaration of Competing Interest

Aeyal Raz reports receiving consultant fees and research support from Medtronic and consultant fees from Neuroindex (none related to this work). All the authors declare that they have no conflicts of interest.

References

  1. Mokdad AH, Forouzanfar MH, Daoud F, Mokdad AA, El Bcheraoui C, Moradi-Lakeh M, et al. Global burden of diseases, injuries, and risk factors for Young people‘s health during 1990-2013: a systematic analysis for the global burden of disease study 2013. Lancet. 2016 Jun 11;387(10036):2383-401.
  2. Nathens AB, Jurkovich GJ, Rivara FP, Maier RV. Effectiveness of state trauma systems in reducing injury-related mortality: a national evaluation. J Trauma. 2000;48(1): 25-31.
  3. Bakalos G, Mamali M, Komninos C, Koukou E, Tsantilas A, Tzima S, et al. Advanced life support versus basic life support in the pre-hospital setting: a meta-analysis. Re- suscitation. 2011 Sep;82(9):1130-7.
  4. Ryynanen OP, Iirola T, Reitala J, Palve H, Malmivaara A. Is advanced life support bet- ter than basic life support in prehospital care? A systematic review. Scand J trauma Resusc. Emerg Med. 2010 Nov 23.;18(1).
  5. Kondo Y, Fukuda T, Uchimido R, Kashiura M, Kato S, Sekiguchi H, et al. Advanced life support vs. basic life support for patients with trauma in prehospital settings: a sys- tematic review and meta-analysis. Front Med. 2021 Mar 26;0:320.
  6. Dehmer JJ, Adamson WT. massive transfusion and blood product use in the pediatric trauma patient. Semin Pediatr Surg. 2010 Nov 1;19(4):286-91.
  7. Figaji AA. Anatomical and physiological differences between children and adults rel- evant to traumatic brain injury and the implications for clinical assessment and care. Front Neurol. 2017 Dec 14;0(DEC):685.
  8. Alemayehu H, Aguayo P. Management of Children with trauma in the PICU: pediat- ric blunt Thoracic trauma. J Pediatr Intensive Care. 2015 Jul 13;4(1):35.
  9. Bankole S, Asuncion A, Ross S, Aghai Z, Nollah L, Echols HD-SS. First responder per- formance in pediatric trauma: a comparison with an adult cohort. Pediatr Crit Care Med. 2011.;12(4).
  10. Sasser SM, Hunt RC, Faul M, Sugerman D, Pearson WS, Dulski T, et al. Guidelines for field triage of injured patients: recommendations of the National Expert Panel on Field Triage, 2011. MMWR Recomm Rep Morb Mortal Wkly RepRecomm Rep. 2012 Jan;61(RR-1):1-20.
  11. Brown JB, Gestring ML, Leeper CM, Sperry JL, Peitzman AB, Billiar TR, et al. The value of the injury severity score in pediatric trauma: time for a new definition of severe injury? J Trauma Acute Care Surg. 2017;82(6):995.
  12. Borgialli DA, Mahajan P, Hoyle JD, Powell EC, Nadel FM, Tunik MG, et al. Performance of the pediatric Glasgow coma scale score in the evaluation of children with blunt head trauma. Acad Emerg Med. 2016;23(8):878-84.
  13. Acker SN, Ross JT, Partrick DA, Tong SBD. Pediatric specific shock index accurately identifies severely injured children. J Pediatr Surg. 2015 Feb 1;50(2):331-4.
  14. Yang YC, Hsieh TH, Liu CY, Chang CY, Hou YT, Lin PC, et al. Analysis of clinical out- come and predictors of mortality in pediatric trauma population: evidence from a 10 year analysis in a single center. Children. 2021 Aug 1.;8(8).
  15. Rozenfeld M, Radomislensky I, Freedman L, Givon A, Novikov I, Peleg K. ISS groups: are we speaking the same language? Inj Prev. 2014 Oct 1;20(5):330-5.
  16. Tiruneh A, Siman-Tov M, Givon A, Peleg K, Bahouth H, Becker A, et al. Comparison between traumatic brain injury with and without concomitant injuries: an analysis based on a national trauma registry 2008-2016. Brain Inj. 2020 Jan 28;34(2): 213-23.
  17. Tiruneh A, Radomislensky I, Bahouth H, Becker A, Hadary A, Jeroukhimov I, et al. Mi- norities and foreign born are disproportionately affected by injuries due to violence: an analysis based on a National Trauma Registry 2008-2017. Isr J Health Policy Res. 2019 Mar 7.;8(1).
  18. Peleg K, Siman-Tov M. Using an optimization model based on Geographic Informa- tion System to determine the dispatch points of ambulances for shortening Response times to road accidents in Israel (Hebrew) [Internet]. [cited 2022 May 27]. Available from: http://www.gertnerinst.org.il/health_policy/trauma/trauma_research/745. htm; 2015.
  19. von Elm E, Altman DG, Egger M, Pocock SJ, Gotzsche PC, Vandenbroucke JP. The strengthening the reporting of observational studies in epidemiology (STROBE) statement: guidelines for reporting observational studies. Lancet. 2007;370(9596): 1453-7.
  20. Huang Y-T, Huang Y-H, Hsieh C-H, Li C-J, Chiu I-M. Comparison of injury severity score, Glasgow coma scale, and revised trauma score in predicting the mortality and prolonged ICU stay of traumatic young children: a Cross-sectional retrospective study. Emerg Med Int. 2019 Dec 1(2019):1-7.
  21. Yousefzadeh-Chabok S, Kazemnejad-Leili E, Kouchakinejad-Eramsadati L, Hosseinpour M, Ranjbar F, Malekpouri R, et al. Comparing pediatric trauma, Glas- gow coma scale and injury severity scores for Mortality prediction in traumatic chil- dren. Ulus Travma Acil Cerrahi Derg. 2016 Jul 1;22(4):328-32.
  22. Cicero MX, Cross KP. Predictive value of initial Glasgow coma scale score in pediatric trauma patients. Pediatr Emerg Care. 2013 Jan;29(1):43-8.
  23. Theodorou CM, Galganski LA, Jurkovich GJ, Farmer DL, Hirose S, Stephenson JT, et al. Causes of early mortality in pediatric trauma patients. J Trauma Acute Care Surg. 2021 Mar 1;90(3):574-81.
  24. Beattie TF, Currie CE, Williams JM, Wright P. Measures of injury severity in child- hood: a critical overview. Inj Prev. 1998 Sep 1;4(3):228-31.
  25. Stevenson M, Segui-Gomez M, Lescohier I, Di Scala C, McDonald-Smith G. An over- view of the injury severity score and the New Injury Severity Score. Inj Prev. 2001 Mar;7(1):10-3.
  26. Liberman M, Mulder D, Sampalis J. Advanced or basic life support for trauma: meta- analysis and critical review of the literature. J Trauma. 2000;49(4):584-99.
  27. Stiell IG, Nesbitt LP, Pickett W, Munkley D, Spaite DW, Banek J, et al. The OPALS major trauma study: impact of advanced life-support on survival and morbidity. C Can Med Assoc J. 2008 Apr 4;178(9):1141.
  28. Sampalis JS, Denis R, Lavoie A, Frechette P, Boukas S, Nikolis A, et al. Trauma care re- gionalization: a process-outcome evaluation. J Trauma Acute Care Surg. 1999;46(4): 565-81.
  29. Gauss T, Ageron FX, Devaud ML, Debaty G, Travers S, Garrigue D, et al. Association of Prehospital Time to in-hospital trauma mortality in a physician-staffed emergency medicine system. JAMA Surg. 2019 Dec 1;154(12):1117-24.
  30. Eckstein M, Chan L, Schneir A, Palmer R. Effect of prehospital advanced life support on outcomes of major trauma patients. J Trauma Acute Care Surg. 2000.;48(4) 643-8.
  31. Bickell WH, Wall MJ, Pepe PE, Martin RR, Ginger VF, Allen MK, et al. Immediate ver- sus delayed fluid resuscitation for hypotensive patients with penetrating torso inju- ries. N Engl J Med. 1994 Oct 27;331(17):1105-9.
  32. Seamon MJ, Doane SM, Gaughan JP, Kulp H, D’Andrea AP, Pathak AS, et al. Prehospi- tal interventions for penetrating trauma victims: a prospective comparison between advanced life support and basic life support. Injury. 2013 May;44(5):634-8.
  33. Pusateri AE, Moore EE, Moore HB, Le TD, Guyette FX, Chapman MP, et al. Association of Prehospital Plasma Transfusion with Survival in trauma patients with hemor- rhagic shock when transport times are longer than 20 minutes: a post hoc analysis

of the PAMPer and COMBAT clinical trials. JAMA Surg. 2020 Feb 1.;155(2) e195085- e195085.

  1. Carlson JN, Gannon E, Clay Mann N, Jacobson KE, Dai M, Colleran C, et al. Pediatric out-of-hospital critical procedures in the United States. Pediatr Crit Care Med. 2015.;16(8) e260-7.
  2. Traff H, Hagander L, Salo M. Association of transport time with adverse outcome in paediatric trauma. BJS Open. 2021 May 7.;5(3).
  3. Gerritse BM, Draaisma JMT, Schalkwijk A, van Grunsven PM, Scheffer GJ. Should EMS-paramedics perform paediatric tracheal intubation in the field? Resuscitation. 2008;79(2):225-9.
  4. Okubo M, Komukai S, Izawa J, Gibo K, Kiyohara K, Matsuyama T, et al. Prehospital ad- vanced airway management for paediatric patients with out-of-hospital cardiac ar- rest: a nationwide cohort study. Resuscitation. 2019;145:175-84.
  5. Gausche M, Lewis RJ, Stratton SJ, Haynes BE, Gunter CS, Goodrich SM, et al. Effect of out-of-hospital pediatric endotracheal intubation on survival and neurological out- come: a controlled clinical trial. JAMA. 2000;283(6):783-90.
  6. Garner AA, Bennett N, Weatherall A, Lee A. Success and complications by team com- position for prehospital paediatric intubation: a systematic review and meta- analysis. Crit Care. 2020 Apr 15;24(1):1-15.
  7. Hansen M, Meckler G, Lambert W, Dickinson C, Dickinson K, Van Otterloo J, et al. Pa- tient safety events in out-of-hospital paediatric airway management: a medical re- cord review by the CSI-EMS. BMJ Open. 2016;6(11):e012259.
  8. Orr RA, Felmet KA, Han Y, McCloskey KA, Dragotta MA, Bills DM, et al. Pediatric spe- cialized transport teams are associated with improved outcomes. Pediatrics. 2009; 124(1):40-8.
  9. Brown JB, Leeper CM, Sperry JL, Peitzman AB, Billiar TR, Gaines BA, et al. Helicopters and injured kids: improved survival with scene air medical transport in the pediatric trauma population. J Trauma Acute Care Surg. 2016 Jan 21;80(5):702-10.
  10. Suominen P, Baillie C, Kivioja A, Korpela R, Rintala R, Silfvast T, et al. Prehospital care and survival of pediatric patients with blunt trauma. J Pediatr Surg. 1998 Sep 1;33 (9):1388-92.
  11. Cudnik MT, Newgard CD, Sayre MR, Steinberg SM. Level I versus level II trauma cen- ters: an outcomes-based assessment. J Trauma Acute Care Surg. 2009;66(5):1321-6.
  12. Sathya C, Alali AS, Wales PW, Scales DC, Karanicolas PJ, Burd RS, et al. Mortality among injured children treated at different trauma center types. JAMA Surg. 2015 Sep 1;150(9):874-81.
  13. Webman RB, Carter EA, Mittal S, Wang J, Sathya C, Nathens AB, et al. Association be- tween trauma center type and mortality among injured Adolescent patients. JAMA Pediatr. 2016 Aug 1;170(8):780-6.
  14. Myers SR, Branas CC, French B, Nance ML, Carr BG. A national analysis of pediatric trauma care utilization and outcomes in the United States. Pediatr Emerg Care. 2019 Jan 1;35(1):1.
  15. Miyata S, Cho J, Park H, Matsushima K, Bliss DW. Comparison of outcomes in severe pediatric trauma at adult trauma centers with different trauma case volumes. J Pediatr Surg. 2017 Nov 1;52(11):1831-5.
  16. Nesje E, Valoy NN, Kruger AJ, Uleberg O. Epidemiology of paediatric trauma in Norway: a single-trauma centre observational study. Int J Emerg Med. 2019 Jul 31;12(1):1-10.
  17. Cotton BA, Nance ML. Penetrating trauma in children. Semin Pediatr Surg. 2004 May

1;13(2):87-97.