Defining Severity, Time-Sensitivity and Predictability of Common Pediatric Injuries

Transcription

1 Defining Severity, Time-Sensitivity and Predictability of Common Pediatric Injuries Joel Stitzel, PhD PI Andrea Doud MD, Ashley Weaver PhD, Jennifer Talton MS, Ryan Barnard MS, Samantha Schoell BS, Wayne Meredith MD, Shayn Martin MD, John Petty MD Wake Forest University School of Medicine, Virginia Tech Wake Forest University Center for Injury Biomechanics

2 Disclosures Funded by the Center for Child Injury Prevention Studies (CChIPS) - Multi-university Industry/University Cooperative Research Center (I/UCRC) Supported by Childress Institute for Pediatric Trauma

3 Injury Severity Measures Currently, the most widely used severity metrics are based upon the Abbreviated Injury Scale (AIS) XXXXXX. X Anatomic classification Severity metric AIS Description 1 Minor 2 Moderate 3 Serious 4 Severe 5 Critical 6 Maximum AIS Severity metrics: Not created for use in children Based on consensus opinion May not capture all aspects of injury that determine need for treatment at a Trauma Center (TC)

4 Injury Severity Scoring Alternative Target injuries: Injuries likely to need treatment at a TC given their severity, time sensitivity and predictability Project Goal: Determine the severity, time-sensitivity & predictability of most common pediatric injuries within 4 age subsets Time- Sensitivity Severity Predictability 0-4 yr 5-9 yr yr yr

5 Severity NTDB utilized to determine mortality risk ratios (MRRs) for the most common pediatric injuries Largest aggregation of trauma registry data MRR = # Dying after injury Total # with injury 0 1 Fewer Patients Dying with Injury (Less Severe) More Patients Dying with Injury (More Severe)

6 Severity The most common pediatric injuries result in differing mortality risks between age groups. Median MRR by Age Group p< p=0.04 p=0.03 Median MRR p< yo 5-9yo 10-14yo 15-18yo n=112 injuries n=125 injuries n=156 injuries n=194 injuries

7 Survey of Expert Opinion Time Sensitivity Experts included pediatric & orthopaedic surgeons and emergency medicine physicians For each injury, experts asked: 1. Does this injury require treatment at a TC? 2. How urgently does the injury require treatment from a scale of 1 (not urgently) to 5 (urgently)?

8 Screen shot of Electronic Survey Time Sensitivity Injury Description: Kidney Laceration, Grade 2

9 Time Sensitivity Scores Injuries in the youngest children are more time sensitive than injuries in the oldest children. Median TS Scores Median Time Sensitivity Scores Scores By Age by Group Age Group p< p= p=0.018 p= year 5-9 year year year n=112 injuries n=125 injuries n=156 injuries n=194 injuries

10 Predictability Predictability Score Consensus-derived Occult Score (survey) Data-Derived Transfer Score (NIS)

11 Consensus-Derived Occult Score Experts surveyed For each question, participants asked to assess the likelihood that the injury might be missed on initial assessment

12 Data-Derived Transfer Score National Inpatient Sample (NIS) - Supported by HCUP - Tracks national trends in health care use Transfer Score = # with Injury transferred to TC Total # with Injury 0 1 Fewer Patients Requiring Transfer = Less Occult More Patients Requiring Transfer = More Occult

13 Median Predictability Score Predictability Scores Injuries in the youngest children less predictable (more occult & more highly transferred) than injuries in older children. Median Predictability Scores By Age Group p=0.001 p< p=0.04 p< p= years 5-9 years years years n=112 injuries n=125 injuries n=156 injuries n=194 injuries

14 AIS Glasses

15 AIS Performance 0-4 year olds Cerebrum Subarachnoid Hemorrhage (AIS 3) Open Tibia Fracture (AIS 3) Severity* 0.69 (High) 0.00 (Low) Time Sensitivity: 0.95 (High) 0.86 (Moderate) Predictability: 0.71 (High) 0.07 (Low) Target Injury Score: *Severity Score = Log-normalized Co-Injury adjusted Mortality Risk Ratio (MRR MAIS )

16 Conclusions Current AIS-based severity metrics not created for children & may not capture all aspects of injury Evaluation of Severity, Time Sensitivity and Predictability provide more robust assessment of injury Time- Sensitivity Predictability Future applications will involve integration of Target Injury Scores into an Advanced Automatic Crash Notification Algorithm Severity

17 Thank you! Questions?

18 BACK-UP SLIDES

19 Determining the Most Frequent Injuries Weighted Injury Count Excluded with MY > 10 yrs (injury data missing) Inclusion Criteria - Age < 19yo - AIS 2+ Injuries %: 195 Unique Injuries 100%: 551 Unique Injuries 120% 100% 80% 60% 40% 20% Cumulative Percent NASS AIS 2+ Injury Ranking 0%

20 Mortality Risk Ratios (MRR) 1 st component of severity score = MRRs Year 1 calculated MRR and MRR MAIS using data Year 2 incorporated NTDB as well Deaths 20 MRR = Total Injured = = MAIS Adjusted MRR (MRR MAIS ) = Deaths w/ MAIS = Injury s AIS Total Injured w/ MAIS = Injury s AIS Excludes patients w/ higher AIS co-injuries AIS 2 Injury: 60 of 100 Injured w/ MAIS =2 = 5 Deaths (MAIS = 2) = Injured (MAIS =2)

21 Distributions of MRR and MRR MAIS by Age Group MRR and MRR MAIS analyses using increased sample sizes Distributions of data remain right-skewed 0-4 years: 5-9 years: MRR MRR MRR MAIS MRR MAIS years: MRR MRR MAIS years: MRR MRR MAIS

22 MRR Severity vs AIS Severity There is an overall positive correlation between AIS Severity and MRR/MRR MAIS. Within each AIS Severity, there, is large variation in MRR & MRR MAIS There are some lower severity AIS scores that have higher MRRs & MRR MAIS than higher severity AIS Scores. Plots for 0-18 years shown below. Plots for other pediatric subsets appear similar. MRR by AIS Severity, 0-18 years MRR MAIS by AIS Severity, 0-18 years y = x R² = y = x R² = MRR y = x x R² = 0.63 MRR MAIS y = x x R² = AIS Severity AIS Severity

23 Comparing Mortality between Adults & Children MRR MAIS for an injury in each pediatric group of note is plotted against the MRR MAIS of that injury in the >/= 19 year (adult) group. Injuries are categorized by body region as noted in the legend. Injuries appearing below the equivalency line demonstrated a greater MRR MAIS for adults than for the stratified pediatric age group of note 1 1 MRR MAIS 0-4 Years MRR MAIS 5-9 Years MRR MAIS >/=19 Years MRR MAIS >/=19 Years Equivalency Line

24 Comparing Mortality between Adults & Children MRR MAIS for an injury in each pediatric group of note is plotted against the MRR MAIS of that injury in the >/= 19 year (adult) group. Injuries are categorized by body region as noted in the legend. Injuries appearing below the equivalency line demonstrated a greater MRR MAIS for adults than for the stratified pediatric age group of note 1 1 MRR MAIS Years MRR MAIS Years MRR MAIS >/= 19 Years MRR MAIS >/= 19 Years Equivalency Line

25 Disability Risk Ratios Mimicking what was done in Potoka et al, we chose to dichotomize FIM Scores FIM FEED FIM LOCOMOT FIM EXPRESS If any of these were 1 or 2 then patient labeled as Disabled (obviously we would explain there are diff levels of disability but all of these patients had some level of more than mild disability at discharge) If all are 3 or 4 then patient is Not disabled For each AIS code, we then calculated the following: DRR = (Disability Risk Ratio) # Disabled after injury Total # with injury

26 Calculation of Time Sensitivity Scores For each injury within each age group, the following were calculated: 1. TC Dec Score = Mean of all TC decision responses (0= Non-TC, 1= TC) 2. Urgency Score = Mean of all Urgency Score responses (1-5) To Calculate the Time Sensitivity (TS) Score, we first calculated an urgency multiplier: Urgency score of 5 shifts up 20% Urgency Multiplier = [0.1 * Urgency Score] The TS Score is then calculated based on the following equation: Urgency score of 1 shifts down 20% TS Score = TC Dec Score +[ Urgency Muliplier TC Dec Score] ( )

27 Severity Score (MRR*) Target Injury Score Time Sensitivity (Urgency + Trauma Decision) Target Injury Score (TIS), 0-3 Predictability (Occult + Transfer Score 0 3 *Log-normalized, future will add evaluation of disability as well