Presentation on theme: "Scene Size-up NOTE: Additional useful information can be found in:"— Presentation transcript:
0International Trauma Life Support, 7e Scene Size-up1Key Lecture PointsExplain the relationship of time to patient survival and how this affects our actions at the scene.Explain the steps of the Scene Size-up and the importance of each step.Explain the importance of being aware of mechanisms of injury.Briefly review the concept of transfer of energy.Stress the concept of the “three collisions.”Briefly review the highlights of specific situations.Large vehicle accidentsFrontal deceleration—effect on driver and passengersLateral impactRear impactRolloverEffect of restraints—lap belts, cross-chest lap belts, and air bagsTractor accidentsSmall vehicle accidentsMotorcyclesAll-terrain vehiclesPersonal watercraftSnowmobilesPedestrian injuriesFallsPenetrating injuriesKnivesGunshot woundsBlast injuries
2Overview Steps of Scene Size-up Two basic mechanisms of motion injury Three collisions associated with MVCsCommon forms of MVCsPotential injuries associated with restraint systemsNOTE: Overview of presentation – continued on next slide.
3Overview Assessment criteria and anticipated injuries from falls Two most common forms of penetrating injuryBlast injury factors related to assessmentNOTE: Overview of presentation.
4Trauma Care Teamwork is important! You must know: What you can handle and what you can'tWhat you should handle and what you shouldn'tWhen to stay and when to leaveFastest route there and fastest route awayWhat to do, what not to do, and when to waitOften patient's life depends on how well you manage details, and not all of details are at scene.You or a member of your team must:Know how to maintain your ambulance or rescue vehicle so that it is serviced and ready to respond when needed.Know quickest way to scene of an injury.Know how to size up a scene in order to recognize dangers and identify mechanisms of injury.Know which scenes are safe and, if not safe, what to do about them.Know when you can handle a situation and when to call for help.Know when to approach patient and when to leave with patient.Know your equipment and maintain it in working order.Know most appropriate hospital and fastest way to get there.Know where to put your hands, which questions to ask, what interventions to perform, when to perform them, and how to perform critical procedures quickly and correctly.
5Scene Size-up A critical part of trauma assessment Anticipate what you will find at sceneAnticipate equipment and resource needsForm a plan of approachBe prepared to modify that planFailure to size-up can jeopardize lives
6Scene Size-up First step in ITLS Primary Survey NOTE: This is presented as an overview for a frame of reference for Scene Size-up. Assessment will be taught in detail in another section.Emphasize that 1st step in assessment is always Scene Size-up.Performing a good Scene Size-up will facilitate a good assessment; a poor Scene Size-up will complicate ensuing assessment and management.
7Scene Size-up Standard precautions Scene safety Initial triage (total number of patients)Need for more help or equipmentMechanism of injuryScene Size-up includes taking standard precautions to prevent exposure to blood and other potentially infective material, evaluating scene for dangers, determining total number of patients, determining essential equipment needed for this particular scene, and identifying mechanisms of injuries.Scene Size-up actually begins at dispatch, with anticipation of what will be found at scene.At that time, think about what equipment will be needed and whether other resources may be needed.Information from dispatch is useful in enabling you to begin to think about a plan, but this information is often exaggerated by caller or even completely wrong. Be prepared to change your plan depending on Scene Size-up.
8Standard PrecautionsExposure to blood or OPIM very likely at a trauma sceneAppropriate PPE must be wornCovered in more detail in Chapter 22NOTE: Covered in more detail in Chapter 22.Trauma scenes are among most likely to subject rescuer to contamination by blood or other potentially infectious material (OPIM).Gloves, eye protection or face shields, impervious gowns as needed.Remember to protect your patient from body fluids by changing gloves between patients.
9Scene Safety Ambulance positioning Windshield survey Safe place to parkFacing away from sceneWindshield surveyThreats to youThreats to/from patientThreats to/from bystandersPosition response vehicle away from hazards, but close enough to retrieve equipment efficiently and in a direction to leave scene easily.Consider using vehicle as barrier to hazards (like oncoming traffic).Windshield survey: Look out windshield for hazards before leaving your response vehicle.Look for hazards as you approach.Courtesy of Bonnie Meneely, EMT-P
10Initial Triage Total number of patients Call for backup Medical commandInitiate MCI protocolsAny more patients?IMAGE: Where are patients at this scene? Where should you look? Where else should you look? It is possible a patient could have been located off-screen to top-left of image.Courtesy of Bonnie Meneely, EMT-P
11Need for More Essential equipment Additional resources Carry to scene for time efficiencyChange gloves between patientsAdditional resourcesCall earlyRelay where to respond and any dangersThe following equipment is always needed for trauma patients:Personal protection equipmentLong backboard with effective strapping and head motion-restriction deviceAppropriately sized rigid cervical extrication collarOxygen and airway equipment (suction equipment, BVM should be included)Trauma box (bandage material, blood pressure cuff, stethoscope)
12Mechanism of Injury Energy follows physics laws. Injuries present in predictable patternsHigh-energy at risk of severe injury.Consider injured until proven otherwiseType of MOIGeneralizedFocusedMissed or overlooked injuries may be catastrophic.5–15% of patients involved in a high-energy event, despite normal vital signs and no apparent anatomic injury on initial assessment, will exhibit severe injuries on later examination.A strong correlation exists between injury severity and automobile velocity changes, as measured by amount of vehicle damage. Severity of vehicle damage has also been suggested as a nonphysiologic triage tool.Generalized mechanisms may require a rapid trauma survey whereas focused mechanisms may only require a focused exam.
13Basic Motion Mechanisms Blunt injuriesRapid forward decelerationRapid vertical decelerationBlunt instrument energy transferPenetrating injuriesProjectilesKnivesFalls upon objectsMotion (mechanical) injuries are by and large responsible for the majority of mortality from trauma in United States and the industrial world .Generally, blunt trauma is more common in rural settings, and penetrating trauma is more common in urban setting.Rapid forward deceleration is usually blunt, but may be penetrating.Most common example of rapid forward deceleration is motor-vehicle collision (MVC).
14Motor-Vehicle Collisions Each collision is three collisions:Machine Collision1Body Collision2Organ Collision3Note: Slide animationConsider all MVCs to occur as three separate events (Figure 1-2).Machine collisionBody collisionOrgan collisionTo explain forces involved, consider Sir Isaac Newton's first law of motion: “A body in motion remains in motion in a straight line unless acted upon by an outside force.”Motion is created by force (energy exchange), and, therefore, force will stop motion.If this energy exchange occurs within body, damage of tissues is produced.
15Other Collisions Secondary collisions Objects are missiles Additional impactsVehicle collides with another objectOther vehicles collide with original vehicleANIMATION: ON CLICK package flies in from left of screen and hits patient's head.Additional impacts may make it more difficult to predict injuries in these cases.Quickly but carefully look for clues inside vehicle.
16Clues to Injury Deformity of vehicle Deformity of interior structures What forces were involved in collision?Deformity of interior structuresWhat did patient hit?Deformity or injury patterns on patientWhat anatomic areas were hit?
18Frontal-Impact Collision Windshield injuriesBrain, soft-tissue injury, cervical spineSteering wheel injuriesTraumatic tattooing of skinDashboard injuriesFace, brain, cervical spine, pelvis, hip, kneeIn head-on collision, the body is brought to a sudden halt, and energy transfer is capable of producing multiple injuries.Windshield injuries: of utmost concern is potential for serious airway and cervical-spine injury.Steering wheel deformity is a cause for alarm and must heighten your index of suspicion. You must also relay this information to receiving physician.Potential injury patterns:Deformed steering wheelCervical-spine fractureDashboard knee imprintsFlail chestSpider deformity of windscreenMyocardial contusionPneumothoraxAortic disruptionSpleen or liver lacerationPosterior hip dislocationKnee dislocation(Courtesy of Maria Dryfhout, Shutterstock )
19Lateral-Impact Collision Similar to frontal-impact with lateral energyNot easily predictedConsider organ damageCheck impact sideHead, neck, upper arm, shoulder, thorax, abdomen, pelvis, legsPotential injury patterns:Contralateral neck sprainCervical-spine fractureLateral flail chestPneumothoraxAortic disruptionDiaphragmatic ruptureLaceration of spleen, liver, kidneyPelvic fracture(Photo courtesy of Anthony Cellitti, NREMT-P)
20Rear-Impact Collision Posterior displacementRapid forward deceleration also possibleHeadrest positionHyperextension injuriesDamage back and frontDeceleration injuriesSudden forward increase in acceleration from rear-impact mechanisms produces posterior displacement of occupants and possible hyperextension of cervical spine if headrest is not properly adjusted.If seat back breaks and falls backward into rear seat, there is greater chance of lumbar-spine injury.Rapid forward deceleration may also occur if car suddenly strikes something in front or if driver applies brakes suddenly.Note deformity of auto anterior and posterior as well as interior deformity and headrest position.Potential injury patterns:Cervical-spine injury(Courtesy of Bonnie Meneely, EMT-P)
21Rollover Collision Multiple impacts Axial-loading injuries Ejection Multiple directionsMultiple injuriesAxial-loading injuriesSpine injuryEjectionChance of death increases 25 timesThe chance for axial-loading injuries of spine is increased in this form of MVC.Courtesy of Bonnie Meneely, EMT-P(Courtesy of Bonnie Meneely, EMT-P)
23Occupant Restraint Lap belt Three-point restraint Air bags Clasp knife effectAbdomenLumbar spineThree-point restraintCervical spineClavicular fractureAir bagsFirst impact onlyAlways “lift and look”Lumbar spineRestrained occupants are more likely to survive a collision, because they are protected from much of impact inside the vehicle and are unlikely to be ejected.If seatbelt is in place and victim is subjected to a frontal deceleration crash, his body tends to fold together like a clasp (or pocket) knife.Air bags aka passive restraints:Do not prevent “down and under” movement, so may still impact with legs and suffer leg, pelvis, or abdominal injuries.Small drivers who bring seat up close to steering wheel may sustain serious injuries as airbag inflates.Infants in car seats placed in the front seat may be seriously injured by air bag.Supplemental restraint systems are only effective if occupant is NOT out of position (OOP).(Courtesy of Olivier Le Queinec, Shutterstock.com)
24Tractor Accidents 50% of farm fatalities Common injuries Side overturns 85%Likely to throw clearRear overturns 15%Likely to entrap or crushCommon injuriesCrush injuriesThermal or chemical burnsTwo basic types of tractors are two-wheel drive and four-wheel drive. In both, center of gravity is high, and thus tractors are easily turned over.The majority of fatal accidents are due to tractor turning over and crushing driver.Primary mechanism is crush injury, and severity depends on part of anatomy involved.Additional mechanisms are chemical burns from gasoline, diesel fuel, hydraulic fluid, or even battery acid.Thermal burns from hot engine parts or ignited fuel are also common.Courtesy of Roy Alson, MD
26Pedestrian Injuries Mechanism Common injuries Primary collision Additional impactsCommon injuriesInternal injuries and fracturesAdult: bilateral leg, kneeChildren: pelvis, torsoIMAGE: “Exploded” leg from being struck by an auto.Pedestrian almost always suffers severe internal injuries as well as fractures.This is true even if vehicle is traveling at low speed.Adult usually has bilateral lower-leg or knee fractures plus whatever secondary injuries occur when body strikes hood of car and then ground.Children are shorter, so bumper is more likely to hit them in pelvis or torso.They usually land on their heads in secondary impact.Courtesy of Bonnie Meneely, EMT-P
28Penetrating Injuries Knife-wound severity Stabilize impaled object Anatomic area penetratedFourth intercostal space may be chest and abdomenLength of bladeAngle of penetrationStabilize impaled objectMinimize external movementIMAGE: Figure 1-16 Stab wounds at nipple level or below frequently penetrate abdomen.Upper abdominal stab wound may cause intrathoracic organ injury, and stab wounds below fourth intercostal space may have penetrated abdomen.Usually stabilize any impaled object in place.Ensure that stabilization minimizes movement of object that will cause further damageImpaled objects in cheek of face and those blocking airway are exceptions to this rule.
29Penetrating Injuries Firearms Type of weapon Caliber Distance traveled Low-velocityHigh-velocityCaliberMissile sizeBullet constructionTumbling/yawDistance traveledIMAGE: High-velocity leg wound. Notice entrance and exit wounds.Remember that you treat patient and wound, not description of weapon.Low-velocity:Less than 2,000 feet per second, include essentially all handguns and some rifles.Injuries are much less destructive than those sustained from high-velocity weapons.High-velocity:Wounds carry additional factor of hydrostatic pressure.Factors that contribute to tissue damage include:Missile size. The larger the bullet, more resistance and larger permanent tract.Bullet constructionMissile deformity. Hollow point and soft nose flatten out on impact, resulting in involvement of a larger surface.Semijacket. The jacket expands and adds to surface area.Tumbling. Tumbling of missile causes a wider path of destruction.Yaw. The missile can oscillate vertically and horizontally (wobble) about its axis, resulting in a larger surface area presenting to tissue.Courtesy of Roy Alson, MD
31Wound Ballistics Factors Missile velocity Missile size Missile deformityMissile designTumbling and yawIMAGE: Figure 1-17b.High velocity is greater than 2,000 feet (610 meters) per second; less than that is low velocity (e.g., handguns, some rifles).Missile deformity: projectile flattens out on impact increasing its surface area and causing more damage.Missile design: semi-jacketed, soft nose, etc., expand differently.Tumbling causes a wider path of destruction.Yaw is the missile wobbling, resulting in a larger area presenting to the tissue.(Courtesy of Roy Alson, MD)
32Wound Ballistics Internal wound Damage proportional to tissue density Tissue contact damageHigh-velocity transfer of energyShock wavesTemporary cavityPulsation of temporary cavityDamage proportional to tissue densityHighly dense tissue sustains more damageIMAGE: Figure 1-17a High-velocity vs. low-velocity injury.Penetrating wounds consist of 3 parts: entry wound, exit wound, and internal wound.Low-velocity projectiles inflict damage by tissue contact.High-velocity projectiles inflict damage by tissue contact and transfer of kinetic energy to surrounding tissues.Shock wavesTemporary cavity, which is 30 to 40 times bullet's diameter and creates immense tissue pressuresPulsation of temporary cavity, which creates pressure changes in adjacent tissueShotgun wounds, injury determined by kinetic energy at impact, which is influenced by:Powder chargeSize of pelletsChoke of muzzleDistance to target
33Blast Injuries Primary Secondary Tertiary Quaternary Initial air blast Material propelledTertiaryImpact on objectQuaternaryDispersed hazardous materialIMAGE: Facial injuries shown here are tertiary from patient being thrown against a wall. Note that patient shown here has “raccoon eyes.”NOTE: Figure 1-19 depicts blast areas.Primary air-blast injuries are almost exclusive to air-containing organs.Secondary injuries may be penetrating or blunt.Tertiary injuries are much same as when a person is ejected from an automobile.Now that terrorists are using explosives to disperse chemical, biological, or radiological material, some classify injuries resulting from this as “quaternary injuries.”
34Scene Size-up is complete! CautionDo not approach untilScene Size-up is complete!
35Summary Time is critical; teamwork is essential Scene size-up can be lifesavingMechanism of injury:An aid to predict injuryPart of overall management of trauma patientRecord scene and mechanism findingsStress need to do an accurate patient assessment.MOI is a tool but not an absolute. We do not know all forces body may have been exposed to.