Documentation:FIB book/problems/Injury Criteria, Scaling, and Databases

Imagine the following scenario: a non-fatal crash involving a head-on collision between an SUV and a tree. At the time of the incident, the vehicle was solely occupied by an unbelted 23-year-old female driver.

A summary of the occupant’s injuries is detailed in Table 1, and a list of the AIS and ISS body regions is given in Table 2.

Table 1 - Injury summary for a hypothetical crash scenario with respective AIS codes.

#	AIS Description	Localizer	AIS Severity
1	Spleen laceration-> total desvascularization; tissue loss; avulsion; massive; completely shattered spleen	No Further Specificity	5
2	Cerebrum brain edema-> mild; compressed ventricles without compressed brain stem cisterns	Right, No Further Specificity	3
3	Thoracic cavity injury Hemopneumothorax	Right, No Further Specificity	3
4	Lung contusion-> unilateral-> major; extensive; massive	Right, Lung Lobe 1 Right, Lung Lobe 2	3
5	Skin/subcutaneous/muscle contusion; hematoma	Right, Forearm	1
6	Talus fracture, fracture line into one joint surface; [includes anterior or posterior talo-calcaneal; tibiotalar; superior or posterior	Right, No Further Specificity	2

Table 2 - List of the AIS and ISS body regions.

AIS Body Regions	ISS Body Regions
1 = Head	Head/Neck
2 = Face	Face
3 = Neck	Chest
4 = Thorax	Abdominal/pelvic contents
5 = Abdomen	Extremities and pelvic girdle
6 = Spine	External
7 = Upper extremity
8 = Lower extremity, pelvis, and buttocks
9 = External (skin) and thermal injuries

_.

Question 1

What are the MAIS and the ISS for this particular injury scenario?

SOLUTION (expand to show)
MAIS = 5 (critical) ISS = 52 (region: abdominal/pelvic contents) + 32 (region: head/neck) + 32 (region: chest) = 25 + 9 + 9 = 43

Question 2

What are the six stages of the AIS?

SOLUTION (expand to show)
1 = minor 2 = moderate 3 = serious 4 = severe 5 = critical 6 = non-survivable/currently untreatable injury

Question 3

What are the main differences between the AIS and the ISS?

SOLUTION (expand to show)

Answers may vary, but at a minimum, should include the bolded content: The AIS indicates the type, location, and severity of a single injury, in isolation from any others. Thus, it does not account for the accumulation of injuries. It is indicative of the likelihood that a person would die from an individual injury. It includes nine body regions and ranges in value from 1 to 6, 1 being a minor incident and 6 denoting an untreatable or non-survivable injury. The ISS provides an overall injury score for patients with multiple injuries. Thus, it accounts for the accumulation of injuries. It includes six body regions (some regions from AIS are combined into a single ISS region), and it ranges from 1 to 75. _________________________ Other relevant information (not part of the solution): To calculate the ISS, the highest AIS values from the 3 most severely injured ISS body regions are squared and summed together. Thus, injuries are not weighted according to body region, and any error to the AIS value is compounded when calculating the ISS. Moreover, if an injury is classified as AIS 6, it automatically receives the maximum ISS value (75).

Question 4

Based on the crash scenario outlined in this problem, name the database that is most commonly used to find information such as that included in Table 1 and the major database in which this particular accident would not be included. Also, describe what type of information is included in these databases.

SOLUTION (expand to show)

At a minimum, your answer should include the bolded content (the wording may vary): CIREN (Crash Injury Research Engineering Network) would include information similar to that written in Table 1. CIREN contains publicly available information collected by a professional accident team about crashes that involved AIS 3+ injuries treated in one major trauma center of the US. It focuses on one injured occupant of the vehicle involved in the accident, which is thoroughly investigated. The database includes a crash summary, an injury analysis, and an injury summary related to that particular occupant. This particular accident would not be included in FARS (Fatality Accident Reporting System) because it involves a non-fatal crash. FARS is a police-collected publicly available database that includes information about all accidents involving fatalities. It does not include accident reconstruction nor biomechanical data.

Question 5

Imagine that the same described accident now involves a fatality. List three questions related to this scenario that could be answered using information from FARS.

SOLUTION (expand to show)

An unlimited number of questions could be answered using information from FARS. Acceptable questions are those related to the crash investigation, the specific type of crash, the day of the week on which the crash occurred, the time of the day that the accident took place, the location of the accident, etc. For example: 1) How many single-vehicle head-on collisions against a tree (standing only) occurred between 2008-2018 in the whole United States? 2) Among these, how many involved alcohol consumption? 3) What percentage of these accidents involving alcohol consumption occurred during the weekend (Friday-Sunday) versus the remainder of the week?