Injury Scoring Assigning an ISS The Trauma Audit

Injury Scoring & Assigning an ISS The Trauma Audit & Research Network (TARN)

Injury Coding Ø Injury coding performed centrally at TARN Ø Ensuring coding uniformity Ø Coders check injury descriptions & imaging reports Ø Abbreviated Injury Scale dictionary (AIS 2005) currently used Ø Every submission assigned an Injury Severity Score (ISS) Ø 75, 000 submissions per year coded

Abbreviated Injury Scale: AIS Ø THE Internationally recognised system for injury scoring Ø Produced by AAAM (Association for the Advancement of Automotive Medicine) in U. S. A Ø Introduced in 1970, originally for Vehicle Crash investigators Ø AIS 2005 version >2000 injury descriptors Ø Anatomically based system, ranking injuries according to severity on a 6 point ordinal scale

AIS: 6 point severity scale AIS (Severity) Grade Injury example 1 Minor Bruise to abdomen 2 Moderate Small Liver laceration 3 Serious Liver laceration with >1 litre of blood loss 4 Severe Ruptured liver 5 Critical Liver laceration involving hepatic vessels 6 Maximum Avulsed liver

AIS Severity indicates The relative risk of “threat to life” in an average person who sustains the coded injury as his or her only injury It’s not a disability scale

AIS code structure: 7 digits Code Injury Numerical identifier Severity Score 853271. 3 Comminuted Femoral Shaft # 853271 . 3 140656. 5 Large Subdural haemorrhage 140656 . 5

Abbreviated Injury Scale: Sections Skin Degloving Penetrating Crush Traumatic Amputation Nerve Hypothermia Asphyxia: Hanging/Strangulation Drowning Frostbite Vessel Joint Skeletal Burns Inhalation Electrocution

AIS: Spinal Injuries Ø Cervical Spine (C 1 -C 7) Ø Thoracic Spine (T 1 -T 12) Ø Lumbar spine (L 1 -L 5) Severity can be affected by location of spinal injury

AIS: Confirmed injuries only Suspected injuries Possible injuries Probable injuries Ruled out injuries

AIS: Not Coded Ø Infections Ø Pneumonia Ø Death Ø Blindness Ø Miscarriage Ø Epilepsy following head injury Ø Pulmonary embolism following skeletal injury Don’t affect Severity score

NFS: Not Further Specified This appears throughout the AIS dictionary & allows the coding of injuries when detailed information is lacking Example: Injury description = Liver laceration Coded as: 541820. 2 (Liver laceration NFS)

AIS 6: Maximum score AIS 6 not used just because a patient dies! Has to be documented medical evidence of an AIS 6 injury

AIS 6: Maximum score Head or Neck ØBrain stem: laceration, crush, penetrating or transection ØC 3 or higher complete cord transection or contusion ØSigmoid or Transverse sinus or Internal carotid artery: Bilateral lacerations Thorax Ø Heart: rupture, multiple lacerations or avulsion Ø Total chest crush Ø Aortic rupture + haemorrhage not confined to mediastinum Ø Bilateral pulmonary artery or vein transection Ø Severe inhalation Abdominal & Pelvic contents Ø Liver avulsion External Ø 2 nd or 3 rd degree burns > 90% Total Body Surface Ø Massive Whole body Explosion type injury

AIS: Localisers 2 additional localiser codes, allow coding of: ØLocaliser 1 Side or aspect of an injury e. g. Right, left, Upper, Temporal, Frontal ØLocaliser 2 Actual Site of an injury e. g. 5 th rib, 12 th Thoracic vertebrae, 2 nd toe Numerical identifier • Don’t affect ISS • Used mainly in Research Severity Localiser 1 Localiser 2

AIS dictionary Available only from: www. aaam. org • • • Latest Version: AIS 2015 recently released $225 each + shipping TARN will moving to AIS 2015 sometime in 2018 All existing codes will be mapped over All Trusts notified well in advance

Injury Coding exercise

EXAMPLE SUBMISSION 1: INJURIES Page AIS code Spiral Shaft of Femur 147 853251. 3 Open complete articular fracture to distal Radius 127 752372. 3 Open book fracture to pelvis with blood loss >20% 159 856164. 5 3 ribs fractured on left 82 450203. 3 Extensive bilateral cerebral contusion 44 140626. 5 Skull vault fracture 49 150400. 2 Grade III (OIS grade) Spleen laceration 96 544224. 3

Calculating the ISS Injury Severity Score

Calculating the ISS: Step 1 Determine the scores of the individual injuries using the Abbreviated Injury Scale

Calculating the ISS: Step 2 Identify the highest severity score in each body area

Injury Severity Score: 6 body areas ØHead & Neck & Cervical spine ØFace ØChest & Thoracic spine ØAbdomen & pelvic contents & Lumbar spine ØExtremities & bony pelvis ØExternal (incl. Skin injuries and Burns)

Head Extensive bilateral cerebral contusion 140626. 5 Skull vault fracture 150400. 2 Thorax 3 ribs fractured on left 450203. 3 Abdomen Grade III Spleen laceration 544224. 3 Extremities Open complete articular fracture to distal Radius 752372. 3 Open book fracture to pelvis with blood loss >20% 856164. 5 Spiral Shaft of Femur 853251. 3

Calculating the ISS: Step 3 Square the highest score in each body area

Head Extensive bilateral cerebral contusion 5² =25 140626. 5 Skull vault fracture 150400. 2 Thorax 3 ribs fractured on left 3² =9 450203. 3 Abdomen Grade III Spleen laceration 3² =9 544224. 3 Extremities Open complete articular fracture to distal Radius 752372. 3 Open book fracture to pelvis with blood loss >20% 5² = 25 856164. 5 Spiral Shaft of Femur 853251. 3

Calculating the ISS: Step 4 ØCode individual injuries ØIdentify the highest score in each body area ØSquare the highest score in each body area ØAdd together the highest AIS 2 from 3 different body areas

Head Extensive bilateral cerebral contusion 5² =25 140626. 5 Skull vault fracture 150400. 2 Thorax 3 ribs fractured on left 3² =9 450203. 3 Abdomen Grade III Spleen laceration 3² =9 544224. 3 Extremities Open complete articular fracture to distal Radius 752372. 3 Open book fracture to pelvis with blood loss >20% 5² = 25 856164. 5 Spiral Shaft of Femur 853251. 3

Injury Severity Score (ISS) = 59

Injury Severity Score (ISS) Body area Injury AIS code Head Closed vault fracture 150402. 2 2² = 4 Thorax 5+6 ribs fractured on left 450202. 2 2² = 4 ISS = 8

Injury Severity Score (ISS) ØRanges from 1 to 75 ØMaximum 75 achieved in 2 ways: 1. Severity 5 in 3 different body areas 52 + 52 = 75 2. ISS convention: AIS = 6 in any body area, ISS = 75

Importance of Injury Detail ØLength, depth or Grade of lacerations (especially to internal organs) ØDepth, size and location of haemorrhages and contusions (especially in the brain) ØOpen or Closed fractures ØStability & site of Fractures (e. g. Comminuted/Displaced Shaft/Proximal/Distal fracture) ØArticular (joint) involvement (e. g. Intra-articular, extra-articular) ØBlood loss ØVessel damage ØLocation & number of rib fractures ØCompression or effacement of ventricles/brain stem cisterns ØNeurology associated with spinal cord injuries ØGrade, Instability, Blood loss or Vascular damage associated with Pelvic Fractures ØCardiac arrest associated with asphyxia or drowning ØEnsure all injuries are documented ØInclude imaging reports or Post Mortems for every submission. Jan 17: Grade now requested for pelvic ring fixations

Probability of Survival Once ISS is assigned Probability of Survival (Ps) calculated each submission

Ps 17 Importance of accurate injury detail Age: 40 Gender: Male ISS: 59 GCS: 5 PMC: i i i Ps 17 calculation $ Ps: 58% Nil

Ps 17 Importance of accurate injury detail Full injury detail Code Spiral Shaft of Femur 853251. 3 Open complete articular fracture to distal Radius 752372. 3 Open book fracture to pelvis with blood loss >20% 856164. 5 3 ribs fractured on left 450203. 3 Extensive bilateral cerebral contusion 140626. 5 Skull vault fracture 150400. 2 Grade III (OIS grade) Spleen laceration 544224. 3 Incomplete injury detail Code Spiral Shaft of Femur 853251. 3 Fracture to distal Radius 752371. 2 Fracture to pelvis 856161. 2 Multiple ribs fractured on left 450210. 2 Cerebral contusion 140604. 3 Skull vault fracture 150400. 2 Spleen laceration 544220. 2 Accurate ISS 59 Incomplete ISS 22 Accurate Ps 58%

Ps 17 Importance of accurate injury detail Age: 40 Gender: Male ISS: 22 GCS: 5 PMC: i i i Ps 17 calculation $ Ps: 86% Nil