Comparing Trauma Severity Scores Injury Severity Score "ISS", Rapid Emergency Medicine Score "REMS" and Kampala Trauma Score "KTS"

Trauma is defined as a physical injury from an external source of sudden onset and severity, which require immediate medical attention.Despite improvements in trauma systems worldwide, trauma continues to be one of the leading causes of death and disability in all age groups, especially the young and middle age group.

Approximately 5.8 million people die each year due to trauma related injuries, representing 8% of the worldwide mortality.Polytrauma is a short verbal equivalent commonly used for severely injured patients usually with associated injury (i.e. two or more severe injuries in at least two different areas of the body), less often with a multiple injury (i.e. two or more severe injuries in one body area).

Polytrauma patients usually have a much higher risk of mortalities and disabilities than the risk of expected mortalities in individual injuries patients. Even though polytrauma can occur due to different causes such as road traffic accidents, fall from heights, bullet injuries, suicide and homicide7.Yet the leading cause of traumatic related causes of death worldwide is road traffic accidents.8 Egypt, in particular, has experienced an alarming increase in the burden of traumatic injuries. According to the World Health Organization In 2015 Egypt has one of the highest rates of road accidents worldwide, with more than 12,000 fatalities each year, one of the highest among EMR countries. Although 90% of world's road trauma related fatalities occur in low- and middle-income countries, Injury prevention and trauma care programs in these countries have remained deficient.

For studying the outcomes of trauma, accurate and reliable methodological tools are required for appropriate scoring of severity and outcome prediction . Trauma scores were designed to facilitate the triage of patients in the ER (emergency room), and identify patients with Polytrauma with low chances of survival. Those scores were meant to organize and improve the quality of trauma care systems, and to assess resources allocation. In 1969, Researchers developed the Abbreviated Injury Scale (AIS) to grade the severity of individual injuries. Attempting to summarize injury severity in patients with multiple traumas with a single number is almost difficult; therefore, multiple alternative scoring systems were proposed afterwards, each with its own problems and limitations.

More than 50 scoring systems have been published for the classification of trauma patients in the field, emergency room, and intensive care settings. There are three main groups of trauma scores: (a) Anatomical, (b) Physiological, (c) Combined scores.

Anatomical scores describe all the injuries recorded by clinical examination, imaging, surgery or autopsy and measure lesion severity. Physiological scores describe changes happened due to the trauma, and translated by changes in vital signs and consciousness. Scores that include both anatomical and physiological criteria (mixed scores) are more useful for patient prognosis

The three types of scores can be combined in different ways to obtain more accurate information from all the possible aspects141- Anatomical Scoring Systems: Abbreviated injury scale (AIS) - Injury severity score (ISS) -New injury severity score (NISS) -Organ injury scale (OIS) - Anatomic profile -International Classification of Diseases (ICD-9) Injury Severity Score (ICISS) 2- Physiological Scoring Systems: Revised trauma score - Glasgow coma score - APACHE scoring (Acute physiology and chronic health evaluation - (APACHE I, II, III) -Rapid Emergency Medicine Score (REMS)3- Combined Anatomical and Physiological Scoring Systems :Trauma and injury severity scores (TRISS) - A severity characterization of trauma (ASCOT)-Kampala Trauma Score (KTS)

What does each score mean? Injury Severity Score (ISS): The injury severity score (ISS) is an anatomical scoring system which provides an overall score for patients with multiple injuries. Each injury is assigned an abbreviated injury scale (AIS) score and allocated to one of six body regions. The highest AIS score of each body region is used. The three most severely injured body regions scores are squared and added together to produce the ISS score.

Rapid Emergency Medicine Score (REMS): Rapid Emergency Medicine Score (REMS) is a newly developed scoring system developed to overcome drawbacks of other scoring systems. It is a simplified version of the APACHE II that allows for rapid score calculation. The REMS is calculated based on the patient's Glasgow Coma Scale (GCS), respiratory rate (RR), oxygen saturation, mean arterial pressure (MAP), heart rate (HR), and age.

Kampala Trauma Score (KTS): A new severity score, Kampala Trauma Score (KTS), was introduced as an injury severity score in settings without advanced diagnostics. This is a simplified composite of the Revised Trauma Score (RTS) and the Injury Severity Score (ISS). The KTS has been validated for its ability to predict outcome in the Ugandan trauma registry.