BACKGROUND:

Hypotension after pediatric traumatic brain injury (TBI) is associated with poor outcomes, but definitions of low systolic blood pressure (SBP) vary. Age- and sex-specific, percentile-based definitions of hypotension may help to better identify children at risk for poor outcomes compared with traditional thresholds recommended in pediatric trauma care.

METHODS:

Using the National Trauma Data Bank between 2007 and 2014, we conducted a retrospective cohort study of children with isolated severe TBI. We classified admission SBP into 5 percentile categories according to population-based values: (1) SBP less than the fifth percentile, (2) SBP in the fifth to 24th percentile, (3) SBP in the 25th to 74th percentile, (4) SBP in the 75th to 94th percentile, and (5) SBP ≥95th percentile. These definitions were compared with the American College of Surgeons (ACS) hypotension definition. The association between SBP percentiles and in-hospital mortality was analyzed by using multivariable Poisson regression models.

RESULTS:

There were 10 473 children with severe TBI included in this study. There were 2388 (22.8%) patients who died while in the hospital. Compared with SBP in the 75th to 94th percentile, mortality was higher with SBP less than the fifth percentile (relative risk [RR] 3.2; 95% confidence interval [CI] 2.9–3.6), SBP in the fifth to 24th percentile (RR 2.3; 95% CI 2.0–2.7), and SBP in the 25th to 74th percentile (RR 1.4; 95% CI 1.2–1.6). An increased risk of mortality with SBP <75th percentile was present across all age subgroups. SBP targets using the ACS hypotension definition were higher than the fifth percentile hypotension definition, but were lower than the 75th percentile hypotension definition.

CONCLUSIONS:

Admission SBP <75th percentile was associated with a higher risk of in-hospital mortality after isolated severe TBI in children. SBP targets based on the 75th percentile were higher compared with traditional ACS targets. Percentile-based SBP targets should be considered in defining hypotension in pediatric TBI.

What’s Known on This Subject:

Hypotension after pediatric traumatic brain injury (TBI) is associated with poor outcomes, but definitions of low systolic blood pressure (SBP) in clinical care vary.

What This Study Adds:

Admission SBP <75th percentile was associated with a higher risk of in-hospital mortality after isolated severe pediatric TBI. Population-based SBP percentile targets may be more appropriate for children with TBI compared with traditional targets.

Traumatic brain injury (TBI) is a leading cause of death and permanent disability in children.1,2 In the United States, ∼60 000 children <18 years old suffer from TBI, and 7600 die because of TBI each year.1 Hypotension early after severe TBI leads to reduced cerebral blood flow, secondary brain injuries, and poor outcomes.3,6 Studies and guidelines reveal mean arterial pressure (MAP) and cerebral perfusion pressure (CPP) as targets for blood pressure, but population-based MAP and CPP nomograms do not exist,7 and CPP may not be determined for hours after severe TBI occurs. Hence, identifying the optimal systolic blood pressure (SBP) definition for hypotension early after severe TBI is clinically important. However, the recommended definitions of systolic hypotension during the early phase of pediatric trauma include the American College of Surgeons (ACS) definition (SBP <70 mm Hg in children <1 year old, SBP <70 mm Hg + [2 × age in years] in children 1–10 years old, and SBP <90 mm Hg in children ≥10 years old) and SBP less than the fifth percentile for age.8,10 Therefore, the optimal SBP target after pediatric severe TBI remains uncertain.

Guideline-based recommendations for blood pressure management in ambulatory pediatric patients and pediatric trauma vary.7,9,10 In 2004 and 2017, population-based, percentile-based SBP data that incorporated age, height, and sex were evaluated in the guidelines from the American Academy of Pediatrics.11,12 However, blood pressure data reported in these guidelines refer mainly to outpatients and have not been examined in pediatric trauma, in which the ACS definition of hypotension is commonly used. Therefore, our aims for this study were to examine the relationship between admission percentile-based definitions of SBP and in-hospital mortality and to compare percentile-based definitions of low blood pressure with the ACS definition in children with severe TBI.

We conducted a retrospective cohort study using the National Trauma Data Bank (NTDB), a centralized national trauma registry created and maintained by the ACS. The NTDB is the largest collection of US trauma registry data, which includes >700 trauma centers, and is provided by the ACS. Since 2007, those at the NTDB instituted greater standardization of data-reporting processes; thus, we used data from the NTDB between 2007 and 2014.13 Because of the deidentified nature of the data set, institutional review board approval was waived for this study.

We included children younger than 18 years old with an International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code for TBI (800.01–800.49, 800.60–800.99, 801.10–801.49, 801.60–801.99, 803.10–803.49, 803.60–803.99, 804.10–804.49, 804.60–804.99, 850.0–854.19, and 959.01) in our study. Severe TBI was defined as having an admission Glasgow Coma Scale (GCS) score ≤8 and a head abbreviated injury scale (AIS) score >3.14 

We excluded patients with missing age data and a head AIS score of 6 because this score represents a nonsurvivable injury. Lastly, we excluded patients with non–head AIS score >2 to limit our population to isolated TBI patients.

Demographic and clinical characteristics examined in the NTDB included age, sex, race, mechanisms of injury, admission GCS score, GCS motor score, injury severity score, head AIS score, admission heart rate, and need for mechanical ventilation during hospitalization. The primary exposure was admission SBP, which we categorized into the following age- and sex-specific percentile groups: group I, SBP less than the fifth percentile; group II, SBP in the fifth to 24th percentile; group III, SBP in the 25th to 74th percentile; group IV, SBP in the 75th to 94th percentile; and group V, SBP ≥95th percentile. Percentile groups were based on data obtained from ∼50 000 healthy children and adolescents from the NHANES, which were used to inform the American Academy of Pediatrics clinical practice guidelines for screening of high blood pressure in children and adolescents in 2004 and 2017.11,12 We used SBP percentile cut points published in the 2004 guidelines because they included population-based data from all children, including children with overweight and obesity, who were excluded in the 2017 guidelines.15 For children <1 year of age, for whom data were not available in the guidelines, we used data published by de Swiet et al.16 We used published SBP cut points for the 50th percentile of height for age and sex for 50th, 75th, and 95th percentile SBPs; we derived cut points for the fifth and 25th percentile SBPs on the basis of provided z scores for calculation in the guideline appendices.12 We also examined SBP thresholds using the ACS guideline–based definition (SBP <70 mm Hg in children <1 year old, SBP <70 mm Hg + [2 × age in years] in children 1–10 years old, and SBP <90 mm Hg in children ≥10 years old). The main outcome of interest was in-hospital mortality.

Descriptive statistics were used to examine demographic and clinical characteristics between groups, which were stratified by admission SBP percentile categories. We calculated the incidence of in-hospital mortality among age-specific SBP percentile categories.

To examine the relationship between age-specific SBP percentiles and in-hospital mortality, we created a causal diagram by using directed acyclic graphs from available NTDB variables to identify the minimum set of potential confounders for adjustment in our statistical models.17 Multivariable Poisson regression models with robust SEs were used to analyze the relationship between early SBP percentiles and in-hospital mortality.

We performed subgroup analyses by age in the following prespecified groups: infants and toddlers (0–4 years old), younger school-aged children (5–9 years old), older school-aged children (10–14 years old), and adolescents (15–17 years old).18 We performed a sensitivity analysis by using a full covariate model (with adjustment for age, sex, GCS motor score, injury severity score, and need for mechanical ventilation), compared with our minimally adjusted final model, to assess the robustness of our findings.

To compare commonly used SBP definitions, we examined the relationship between age- and sex-specific, population-based SBP percentiles and in-hospital mortality and then compared these blood pressure values with ACS guideline–based recommendations for children with isolated severe TBI.

After all exclusions, 10 473 children were included in the final cohort. Demographic characteristics are listed in Table 1. The most common age group was 0 to 4 years old (44.8%), and 5694 (54.4%) children had early SBP ≥95th percentile. Patients were predominantly boys (67.1%), and the majority of patients in our study were white (5719; 54.6%). Motor vehicle–related injuries were the predominant mechanism of injury (26.3%). The median (interquartile range) admission GCS, GCS motor, and head AIS scores were 3 (3–5), 1 (1–2), and 4 (4–4), respectively.

TABLE 1

Demographic and Clinical Characteristics of Children With Isolated Severe TBI Included in the NTDB From 2007 to 2014 Stratified by SBP Percentile Groups

VariablesTotalSBP Percentilea
Less Than the FifthFifth–24th25th–74th75th–94th≥95th
All, n (%) 10 473 (100) 732 (6.9) 529 (5.1) 1539 (14.7) 1979 (18.9) 5694 (54.4) 
Patient demographics, n (%)       
 Boy 7022 (67.1) 472 (64.5) 337 (63.7) 984 (63.9) 1292 (65.3) 3937 (69.1) 
 Race       
  White 5719 (54.6) 385 (52.6) 286 (54.1) 831 (54.0) 1106 (55.9) 3111 (54.6) 
  African American 1775 (17.0) 160 (21.9) 105 (19.8) 245 (15.9) 291 (14.7) 974 (17.1) 
  Hispanic 1636 (15.6) 107 (14.6) 63 (11.9) 252 (16.4) 304 (15.4) 910 (16.0) 
  Asian American or Pacific Islander 169 (1.6) 11 (1.5) 9 (1.7) 21 (1.4) 29 (1.5) 99 (1.7) 
  Other or unknown 1174 (11.2) 69 (9.4) 66 (12.5) 190 (12.3) 249 (12.5) 600 (10.6) 
Mechanism of injury, n (%)       
 Motor vehicle related 2760 (26.3) 185 (25.3) 139 (26.2) 371 (24.1) 499 (25.2) 1566 (27.5) 
 Fall 2070 (19.7) 80 (10.9) 85 (16.1) 315 (20.5) 449 (22.7) 1141 (20.0) 
 Transport, other 1065 (10.6) 46 (6.3) 33 (6.2) 158 (10.3) 203 (10.3) 625 (11.0) 
 Firearm 871 (8.2) 169 (23.1) 50 (9.5) 122 (7.9) 122 (6.2) 408 (7.2) 
 Struck by or against 859 (8.1) 30 (4.1) 36 (6.8) 121 (7.9) 181 (9.1) 491 (8.6) 
 Others, unspecified, or missing 2848 (27.1) 222 (30.3) 186 (35.2) 452 (29.3) 525 (26.5) 1463 (25.7) 
Clinical characteristics       
 Admission GCS score, median (IQR) 3 (3–5) 3 (3–3) 3 (3–3) 3 (3–5) 3 (3–6) 3 (3–5) 
 GCS motor score, median (IQR) 1 (1–2) 1 (1–1) 1 (1–1) 1 (1–2) 1 (1–3) 1 (1–3) 
 Head AIS score, median (IQR) 4 (4–4) 4 (4–5) 4 (4–5) 4 (4–4) 4 (4–4) 4 (4–4) 
 Injury severity score, median (IQR) 20 (16–25) 25 (17–26) 25 (16–26) 20 (16–25) 17 (16–25) 20 (16–25) 
 Admission heart rate, median (IQR) 112 (88–139) 110 (81–138) 118 (90–145) 111 (85–139) 109 (88–137) 113 (90–139) 
 Need for a ventilation, n (%) 7523 (71.8) 562 (76.8) 395 (74.7) 1076(69.9) 1338(67.6) 4152(72.9) 
VariablesTotalSBP Percentilea
Less Than the FifthFifth–24th25th–74th75th–94th≥95th
All, n (%) 10 473 (100) 732 (6.9) 529 (5.1) 1539 (14.7) 1979 (18.9) 5694 (54.4) 
Patient demographics, n (%)       
 Boy 7022 (67.1) 472 (64.5) 337 (63.7) 984 (63.9) 1292 (65.3) 3937 (69.1) 
 Race       
  White 5719 (54.6) 385 (52.6) 286 (54.1) 831 (54.0) 1106 (55.9) 3111 (54.6) 
  African American 1775 (17.0) 160 (21.9) 105 (19.8) 245 (15.9) 291 (14.7) 974 (17.1) 
  Hispanic 1636 (15.6) 107 (14.6) 63 (11.9) 252 (16.4) 304 (15.4) 910 (16.0) 
  Asian American or Pacific Islander 169 (1.6) 11 (1.5) 9 (1.7) 21 (1.4) 29 (1.5) 99 (1.7) 
  Other or unknown 1174 (11.2) 69 (9.4) 66 (12.5) 190 (12.3) 249 (12.5) 600 (10.6) 
Mechanism of injury, n (%)       
 Motor vehicle related 2760 (26.3) 185 (25.3) 139 (26.2) 371 (24.1) 499 (25.2) 1566 (27.5) 
 Fall 2070 (19.7) 80 (10.9) 85 (16.1) 315 (20.5) 449 (22.7) 1141 (20.0) 
 Transport, other 1065 (10.6) 46 (6.3) 33 (6.2) 158 (10.3) 203 (10.3) 625 (11.0) 
 Firearm 871 (8.2) 169 (23.1) 50 (9.5) 122 (7.9) 122 (6.2) 408 (7.2) 
 Struck by or against 859 (8.1) 30 (4.1) 36 (6.8) 121 (7.9) 181 (9.1) 491 (8.6) 
 Others, unspecified, or missing 2848 (27.1) 222 (30.3) 186 (35.2) 452 (29.3) 525 (26.5) 1463 (25.7) 
Clinical characteristics       
 Admission GCS score, median (IQR) 3 (3–5) 3 (3–3) 3 (3–3) 3 (3–5) 3 (3–6) 3 (3–5) 
 GCS motor score, median (IQR) 1 (1–2) 1 (1–1) 1 (1–1) 1 (1–2) 1 (1–3) 1 (1–3) 
 Head AIS score, median (IQR) 4 (4–4) 4 (4–5) 4 (4–5) 4 (4–4) 4 (4–4) 4 (4–4) 
 Injury severity score, median (IQR) 20 (16–25) 25 (17–26) 25 (16–26) 20 (16–25) 17 (16–25) 20 (16–25) 
 Admission heart rate, median (IQR) 112 (88–139) 110 (81–138) 118 (90–145) 111 (85–139) 109 (88–137) 113 (90–139) 
 Need for a ventilation, n (%) 7523 (71.8) 562 (76.8) 395 (74.7) 1076(69.9) 1338(67.6) 4152(72.9) 

IQR, interquartile range.

a

Sex-specific SBP at 50th percentile of height.

Overall, 2388 (22.8%) patients died. Table 2 reveals the mortality rate, which is stratified by admission SBP percentile. The greatest proportion of in-hospital mortality occurred in children with SBP less than the fifth percentile (66.3%; 95% confidence interval [CI] 62.7%–69.7%), followed by SBP in the fifth to 24th percentile (40.1%; 95% CI 35.9%–44.4%) and SBP in the 25th to 74th percentile (23.2%; 95% CI 21.1%–25.4%). The lowest rate of in-hospital mortality was in the group with SBP in the 75th to 94th percentile; therefore, we used SBP in the 75th to 94th percentile as a reference group. Compared with SBP in the 75th to 94th percentile, in-hospital mortality increased in all groups with lower early SBP (SBP less than the fifth percentile [relative risk (RR) 3.2; 95% CI 2.9–3.6], SBP in the fifth to 24th percentile [RR 2.3; 95% CI 2.0–2.7], and SBP in the 25th to 74th percentile [RR 1.4; 95% CI 1.2–1.6]). However, the risk of in-hospital mortality was not significantly different when compared with the group with SBP ≥95th percentile (RR 1.1; 95% CI 0.9–1.2; Table 2).

TABLE 2

Risks of Death Associated With Different SBP Percentiles in Children With Isolated Severe TBI

SBP PercentileaTotal (n = 10 473)Death (n = 2388)Mortality Rate (Total = 22.8%), %95% CIUnivariateMultivariate
RR (95% CI)Adjusted RR (95% CI)
Less than the fifth 732 485 66.3 62.7–69.7 4.1 (3.7–4.6) 3.2 (2.9–3.6) 
Fifth–24th 529 212 40.1 35.9–44.4 2.5 (2.2–2.9) 2.3 (2.0–2.7) 
25th–74th 1539 357 23.2 21.1–25.4 1.4 (1.3–1.7) 1.4 (1.2–1.6) 
75th–94th 1979 316 16.0 14.4–17.7 1.0 (reference group) 1.0 (reference group) 
≥95th 5694 1018 17.9 16.9–18.9 1.1 (0.99–1.3) 1.1 (0.96–1.2) 
SBP PercentileaTotal (n = 10 473)Death (n = 2388)Mortality Rate (Total = 22.8%), %95% CIUnivariateMultivariate
RR (95% CI)Adjusted RR (95% CI)
Less than the fifth 732 485 66.3 62.7–69.7 4.1 (3.7–4.6) 3.2 (2.9–3.6) 
Fifth–24th 529 212 40.1 35.9–44.4 2.5 (2.2–2.9) 2.3 (2.0–2.7) 
25th–74th 1539 357 23.2 21.1–25.4 1.4 (1.3–1.7) 1.4 (1.2–1.6) 
75th–94th 1979 316 16.0 14.4–17.7 1.0 (reference group) 1.0 (reference group) 
≥95th 5694 1018 17.9 16.9–18.9 1.1 (0.99–1.3) 1.1 (0.96–1.2) 
a

SBP by 50th percentile of height.

A subgroup analysis revealed an increased risk of in-hospital mortality in children who had early SBP <75th percentile across all age groups, with the highest risk being among patients with SBP less than the fifth percentile (Fig 1). Overall, compared with SBP in the 75th to 94th percentile, SBP ≥95th percentile was not associated with an increased risk of mortality except for children ages 15 to 17 years (RR 1.4; 95% CI 1.1–1.7; Fig 1). Sensitivity analyses revealed no significant differences in the risk ratios or statistical significance in both the fully and minimally adjusted multivariable models.

FIGURE 1

Multivariate analysis of the association between early SBP percentiles and mortality by age group by using age-specific SBP in the 75th to 94th percentiles as a reference group. a SBP by 50th percentile of height.

FIGURE 1

Multivariate analysis of the association between early SBP percentiles and mortality by age group by using age-specific SBP in the 75th to 94th percentiles as a reference group. a SBP by 50th percentile of height.

Close modal

The values of age-specific SBP thresholds for hypotension in which different definitions (SBP less than the fifth percentile, ACS definition, SBP <25th percentile, and SBP <75th percentile) are used are shown in Table 3. Overall, SBP values from the fifth percentile definition are the lowest, whereas the SBP values from the 75th percentile definition are the highest. SBP targets in which the ACS definition of hypotension (SBP <70 mm Hg in children <1 year old, SBP <70 mm Hg + [2 × age in years] in children 1–10 years old, and SBP <90 mm Hg in children ≥10 years old) is used were generally higher than the fifth percentile hypotension definition but <75th percentile hypotension definition.

TABLE 3

Comparison of SBP Thresholds for Varying Definitions of Hypotension by Age and Percentile-Based Definitions

Age, yFifth Percentile, mm HgACS Definition,a mm HgSBP 25th Percentile,b mm HgSBP 75th Percentile,b mm Hg
BoysGirlsBoysGirls
60 70 78 76 92 84 
70 72 78 78 92 85 
70 74 81 79 95 86 
75 76 84 81 98 89 
75 78 86 82 100 90 
75 80 88 84 102 92 
80 82 89 86 103 94 
80 84 90 88 104 96 
80 86 92 89 106 97 
80 88 93 91 107 99 
10 80 90 95 93 109 101 
11 80 90 97 95 111 103 
12 80 90 99 97 113 105 
13 90 90 101 99 115 107 
14 90 90 104 100 118 108 
15 90 90 106 101 120 109 
16 90 90 109 101 123 109 
17 90 90 111 101 125 109 
Age, yFifth Percentile, mm HgACS Definition,a mm HgSBP 25th Percentile,b mm HgSBP 75th Percentile,b mm Hg
BoysGirlsBoysGirls
60 70 78 76 92 84 
70 72 78 78 92 85 
70 74 81 79 95 86 
75 76 84 81 98 89 
75 78 86 82 100 90 
75 80 88 84 102 92 
80 82 89 86 103 94 
80 84 90 88 104 96 
80 86 92 89 106 97 
80 88 93 91 107 99 
10 80 90 95 93 109 101 
11 80 90 97 95 111 103 
12 80 90 99 97 113 105 
13 90 90 101 99 115 107 
14 90 90 104 100 118 108 
15 90 90 106 101 120 109 
16 90 90 109 101 123 109 
17 90 90 111 101 125 109 
a

SBP <70 mm Hg in infants (1–12 mo old), SBP <70 mm Hg + (2 × age in y) in children 1–10 y of age, and SBP <90 mm Hg in children ≥10 y of age.

b

SBP by 50th percentile of height (based on sex).

The main findings in this study of children with severe isolated TBI are that (1) admission SBP <75th percentile was associated with an increased risk of in-hospital mortality, and (2) 75th percentile–based SBP targets were higher compared with the traditional ACS hypotension definition. This is the largest study in which recommended definitions of systolic hypotension in severe pediatric TBI are compared.

Researchers of only a few small retrospective studies have examined the association of early blood pressure and outcomes after pediatric TBI. Similar to present findings, results from previous pediatric studies revealed that higher SBP is common after pediatric TBI and is associated with better outcomes. An analysis of 18 135 children with blunt trauma revealed that severely injured children (with and without TBI) were relatively hypertensive compared to acute pediatric life support norms.19 White et al20 performed a retrospective cohort study in 136 children with severe TBI and reported higher odds of survival in children who had a maximum SBP ≥135 mm Hg. In a small, single-center study, we previously examined the relationship between age-appropriate SBP percentiles and outcomes after TBI in 172 children with severe TBI21 and reported that age-appropriate SBP <75th percentile was associated with poor outcomes, and our present findings are used to validate these previous observations. Taken together, these data reveal that the previously used definitions for systolic hypotension after TBI may be too low.

Because of an absence of supportive evidence, recommendations for SBP management in severe pediatric TBI, which composed a chapter in the original 2003 Brain Trauma Foundation guidelines, were removed from the most recent 2012 Brain Trauma Foundation guidelines.22,23 However, clinicians who care for children with severe TBI during the resuscitation phase of severe TBI use SBP to diagnose and treat hypotension. It is to bridge this gap in knowledge that we undertook this study. In the current study, SBP <25th percentile was associated with a twofold-higher risk of mortality compared with SBP ≥75th percentile, and the lowest risk of mortality was associated with SBP ≥75th percentile in children <15 years old. Therefore, present data reveal that to accurately identify those who have poor outcomes related to systolic hypotension, a percentile-based definition of hypotension should be considered. We speculate that active hemodynamic management may be required to achieve this SBP ≥75th percentile target and improve outcomes after TBI, but further study of strategies to achieve this goal is required.

The physiologic effect of higher blood pressures on brain outcomes is important and merits some discussion. The observation of a high SBP after TBI may be explained by an excessive release of catecholamines, which may be necessary to maintain CPP, especially if cerebral autoregulation is impaired.24,25 Moreover, the lower limit of cerebral autoregulation in children and adolescents has been reported to be similar to that of adults (range of 46–70 mm Hg), suggesting less autoregulatory reserve (the difference between the MAP and the lower limit of autoregulation) for younger children, whose baseline blood pressures are lower than those of older children.26 Thus, to maintain adequate CPP above the lower limit of cerebral autoregulation (ie, to achieve CPP above a threshold value that provides adequate cerebral blood flow), blood pressure may need to be raised to supranormal ranges. This physiologic response may explain the observed benefit of early SBP ≥75th percentile values, including hypertensive range values (SBP ≥95th percentile), and its association with better outcomes in children <15 years old.

There are some limitations to our study. First, this was a retrospective cohort study, and we relied on recorded data. Second, we did not have data on admission MAP, intracranial pressure, and other confounders (eg, blood gas data, glucose, temperature, and coagulation) on arrival to the hospital.27 Thus, in our analysis, we could not fully consider other blood pressure thresholds. Third, our data did not allow for us to examine the relationship between SBP percentile beyond admission and mortality. Fourth, because we used percentile data from the 2004 blood pressure guidelines rather than the 2017 guidelines (which excluded children with overweight and obesity), high blood pressure cut points used in our study may be on average 2 to 3 mm Hg higher than when using the 2017 guidelines. However, for purposes of this study, the 2004 references are more appropriate, and the range of error in SBP percentile thresholds is expected to be small. Finally, because of the limitation of granular data available for inclusion in this administrative data set, we cannot fully exclude the presence of residual confounding in our multivariable analyses. Despite these limitations, however, we provide a new perspective to answering the question of how to best define systolic hypotension in severe TBI. Our clinical model of a large number of patients without polytrauma allows us to gain a better understanding focused on TBI alone.

Admission SBP <75th percentile was associated with a higher risk of in-hospital mortality after severe isolated TBI in children. SBP targets based on the 75th percentile were higher compared with traditional ACS targets. Percentile-based SBP targets should be considered in defining hypotension in pediatric TBI.

     
  • ACS

    American College of Surgeons

  •  
  • AIS

    abbreviated injury scale

  •  
  • CI

    confidence interval

  •  
  • CPP

    cerebral perfusion pressure

  •  
  • GCS

    Glasgow Coma Scale

  •  
  • MAP

    mean arterial pressure

  •  
  • NTDB

    National Trauma Data Bank

  •  
  • RR

    relative risk

  •  
  • SBP

    systolic blood pressure

  •  
  • TBI

    traumatic brain injury

Drs Suttipongkaset, Chaikittisilpa, Vavilala, Lele, Watanitanon, Chandee, and Krishnamoorthy conceptualized and designed the study, conducted the analyses, drafted the initial manuscript, and reviewed and revised the manuscript; and all authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

FUNDING: No external funding.

1
Schneier
AJ
,
Shields
BJ
,
Hostetler
SG
,
Xiang
H
,
Smith
GA
.
Incidence of pediatric traumatic brain injury and associated hospital resource utilization in the United States.
Pediatrics
.
2006
;
118
(
2
):
483
492
[PubMed]
2
Gross
BW
,
Edavettal
MM
,
Cook
AD
, et al
.
Big children or little adults? A statewide analysis of adolescent isolated severe traumatic brain injury outcomes at pediatric versus adult trauma centers.
J Trauma Acute Care Surg
.
2017
;
82
(
2
):
368
373
[PubMed]
3
Zebrack
M
,
Dandoy
C
,
Hansen
K
,
Scaife
E
,
Mann
NC
,
Bratton
SL
.
Early resuscitation of children with moderate-to-severe traumatic brain injury.
Pediatrics
.
2009
;
124
(
1
):
56
64
[PubMed]
4
Chesnut
RM
,
Marshall
LF
,
Klauber
MR
, et al
.
The role of secondary brain injury in determining outcome from severe head injury.
J Trauma
.
1993
;
34
(
2
):
216
222
[PubMed]
5
Pigula
FA
,
Wald
SL
,
Shackford
SR
,
Vane
DW
.
The effect of hypotension and hypoxia on children with severe head injuries.
J Pediatr Surg
.
1993
;
28
(
3
):
310
314; discussion 315–316
[PubMed]
6
Kokoska
ER
,
Smith
GS
,
Pittman
T
,
Weber
TR
.
Early hypotension worsens neurological outcome in pediatric patients with moderately severe head trauma.
J Pediatr Surg
.
1998
;
33
(
2
):
333
338
[PubMed]
7
Kochanek
PM
,
Carney
N
,
Adelson
PD
, et al;
American Academy of Pediatrics Section on Neurological Surgery
;
American Association of Neurological Surgeons
;
Congress of Neurological Surgeons
;
Child Neurology Society
;
European Society of Pediatric and Neonatal Intensive Care
;
Neurocritical Care Society
;
Pediatric Neurocritical Care Research Group
;
Society of Critical Care Medicine
;
Paediatric Intensive Care Society UK
;
Society for Neuroscience in Anesthesiology and Critical Care
;
World Federation of Pediatric Intensive and Critical Care Societies
.
Guidelines for the acute medical management of severe traumatic brain injury in infants, children, and adolescents–second edition [published correction appears in Pediatr Crit Care Med. 2012;13(2):252].
Pediatr Crit Care Med
.
2012
;
13
(
suppl 1
):
S1
S82
[PubMed]
8
Adelson
PD
,
Bratton
SL
,
Carney
NA
, et al;
American Association for Surgery of Trauma
;
Child Neurology Society
;
International Society for Pediatric Neurosurgery
;
International Trauma Anesthesia and Critical Care Society
;
Society of Critical Care Medicine
;
World Federation of Pediatric Intensive and Critical Care Societies
.
Guidelines for the acute medical management of severe traumatic brain injury in infants, children, and adolescents. Chapter 4. Resuscitation of blood pressure and oxygenation and prehospital brain-specific therapies for the severe pediatric traumatic brain injury patient.
Pediatr Crit Care Med
.
2003
;
4
(
suppl 3
):
S12
S18
[PubMed]
9
Badjatia
N
,
Carney
N
,
Crocco
TJ
, et al;
Brain Trauma Foundation
;
BTF Center for Guidelines Management
.
Guidelines for prehospital management of traumatic brain injury 2nd edition.
Prehosp Emerg Care
.
2008
;
12
(
suppl 1
):
S1
S52
10
de Caen
AR
,
Berg
MD
,
Chameides
L
, et al
.
Part 12: pediatric advanced life support: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care.
Circulation
.
2015
;
132
(
18, suppl 2
):
S526
S542
[PubMed]
11
National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents
.
The fourth report on the diagnosis, evaluation, and treatment of high blood pressure in children and adolescents.
Pediatrics
.
2004
;
114
(
suppl 2, 4th report
):
555
576
12
Flynn
JT
,
Kaelber
DC
,
Baker-Smith
CM
, et al;
Subcommittee on Screening and Management of High Blood Pressure in Children
.
Clinical practice guideline for screening and management of high blood pressure in children and adolescents [published correction appears in Pediatrics. 2017;140(6):e20173035].
Pediatrics
.
2017
;
140
(
3
):
e20171904
[PubMed]
13
Haider
AH
,
Saleem
T
,
Leow
JJ
, et al
.
Influence of the National Trauma Data Bank on the study of trauma outcomes: is it time to set research best practices to further enhance its impact?
J Am Coll Surg
.
2012
;
214
(
5
):
756
768
[PubMed]
14
Timmons
SD
,
Bee
T
,
Webb
S
,
Diaz-Arrastia
RR
,
Hesdorffer
D
.
Using the abbreviated injury severity and Glasgow Coma Scale scores to predict 2-week mortality after traumatic brain injury.
J Trauma
.
2011
;
71
(
5
):
1172
1178
[PubMed]
15
Flynn
JT
,
Falkner
BE
.
New clinical practice guideline for the management of high blood pressure in children and adolescents.
Hypertension
.
2017
;
70
(
4
):
683
686
[PubMed]
16
de Swiet
M
,
Fayers
P
,
Shinebourne
EA
.
Systolic blood pressure in a population of infants in the first year of life: the Brompton study.
Pediatrics
.
1980
;
65
(
5
):
1028
1035
[PubMed]
17
Textor
J
,
Hardt
J
,
Knüppel
S
.
DAGitty: a graphical tool for analyzing causal diagrams.
Epidemiology
.
2011
;
22
(
5
):
745
[PubMed]
18
Keenan
HT
,
Bratton
SL
.
Epidemiology and outcomes of pediatric traumatic brain injury.
Dev Neurosci
.
2006
;
28
(
4–5
):
256
263
[PubMed]
19
Loizou
E
,
Bouamra
O
,
Dark
P
,
Martin
B
,
Lecky
F
.
Comparing the systolic blood pressure (SBP) and pulse rate (PR) in injured children with and without traumatic brain injury.
Resuscitation
.
2010
;
81
(
4
):
418
421
[PubMed]
20
White
JR
,
Farukhi
Z
,
Bull
C
, et al
.
Predictors of outcome in severely head-injured children.
Crit Care Med
.
2001
;
29
(
3
):
534
540
[PubMed]
21
Vavilala
MS
,
Bowen
A
,
Lam
AM
, et al
.
Blood pressure and outcome after severe pediatric traumatic brain injury.
J Trauma
.
2003
;
55
(
6
):
1039
1044
[PubMed]
22
Carney
N
,
Totten
AM
,
O’Reilly
C
, et al
.
Guidelines for the management of severe traumatic brain injury, fourth edition.
Neurosurgery
.
2017
;
80
(
1
):
6
15
[PubMed]
23
Bratton
SL
,
Chestnut
RM
,
Ghajar
J
, et al;
Brain Trauma Foundation
;
American Association of Neurological Surgeons
;
Congress of Neurological Surgeons
;
Joint Section on Neurotrauma and Critical Care, AANS/CNS
.
Guidelines for the management of severe traumatic brain injury. I. Blood pressure and oxygenation [published correction appears in J Neurotrauma. 2008;25(3):276–278].
J Neurotrauma
.
2007
;
24
(
suppl 1
):
S7
S13
[PubMed]
24
Krishnamoorthy
V
,
Chaikittisilpa
N
,
Kiatchai
T
,
Vavilala
M
.
Hypertension after severe traumatic brain injury: friend or foe?
J Neurosurg Anesthesiol
.
2017
;
29
(
4
):
382
387
[PubMed]
25
Bouma
GJ
,
Muizelaar
JP
,
Bandoh
K
,
Marmarou
A
.
Blood pressure and intracranial pressure-volume dynamics in severe head injury: relationship with cerebral blood flow.
J Neurosurg
.
1992
;
77
(
1
):
15
19
[PubMed]
26
Vavilala
MS
,
Lee
LA
,
Boddu
K
, et al
.
Cerebral autoregulation in pediatric traumatic brain injury.
Pediatr Crit Care Med
.
2004
;
5
(
3
):
257
263
27
Guilliams
K
,
Wainwright
MS
.
Pathophysiology and management of moderate and severe traumatic brain injury in children.
J Child Neurol
.
2016
;
31
(
1
):
35
45
[PubMed]

Competing Interests

POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.

FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.