Trauma Morbidity and Mortality Mod III 2012 ECRN CE Condell Medical Center EMS System Site Code: 107200E -1212 Prepared by: Sharon Hopkins, RN, BSN, EMT-P 1 Objectives Upon successful completion of this module, the ECRN will be able to: 1. Identify by mechanism of injury and signs and symptoms major causes of increased risk of morbidity & mortality related to a traumatic injury (airway obstruction, flail chest, open pneumothorax, tension pneumothorax, cardiac tamponade, aortic tear). 2. Identify the significance and signs and symptoms of crush injuries and compartment syndrome. 3. Describe field treatment based on injury presented. 2 Objectives cont’d 4. Identify transport destination decision per Region X SOP. 5. Review case scenarios presented. 6. Review the skills of needle decompression, cricothyrotomy, and QuickTrach 7. Successfully complete the post quiz with a score of 80% or better. 3 Thoracic Trauma Responsible for 20-25% of all trauma related deaths Purpose of primary assessment Determine the presence of any LIFE THREATS!!! What’s going to kill the patient the fastest?? Hypoxia Hemorrhage 4 Trauma Stats Deaths at the scene are usually due to injury of the heart and/or great vessels Deaths delayed by hours are usually due to airway obstruction, tension pneumothorax, hemorrhage, and tamponade Note: only a small portion of patients with traumatic injuries to the chest need OR 5 Tissue Hypoxia Inadequate delivery of oxygen to tissues can be caused by a variety of mechanisms Start patient assessments with primary assessment Any change in the patient condition and you should repeat the primary assessment A–B-C 6 Causes of Tissue Hypoxia Hypovolemia from loss of blood volume Ventilation/perfusion mismatch due to injury of lung tissue Compromise to ventilations and or circulation due to a tension pneumothorax Pump failure from severe myocardial injury or pericardial tamponade 7 Thoracic Cage A skeletal protection to many organs Lungs Heart Great vessels Spinal cord Liver Stomach Spleen Pancreas Kidneys Transverse colon Trauma to the protective rib cage may also cause some injuries 8 Diaphragm Position: lies at the level following the curve of the lower 6 ribs and connected to the xyphoid process Main function: respirations Descends/flattens on inspiration Rises on exhalation Innervation: phrenic nerve which begins C3 to C5 level Injury above C3 patient unable to breathe Injury below C5 patient can still initiate breathes 9 Diaphragm 10 Diaphragm – A Moving Target Palpate and place your finger tips at the lower edge of your rib cage Keep your fingers in contact with your skin Take a deep breath Feel your rib cage flare out Diaphragm drawn downward moving lungs and abdominal organs downward to accommodate lung expansion Now exhale Feel your rib cage decrease in size Your diaphragm rises as lung capacity decreases 11 Anatomy – Chest Contents Contents above the diaphragm Lungs Lower trachea Main stem bronchi Heart and great vessels Esophagus These organs sit above the diaphragm 12 Anatomy – Chest Contents Contents in the lower chest cavity in upper abdominal region Stomach Spleen Liver Kidneys Pancreas These organs are separated from the upper chest by the diaphragm If diaphragm ruptures, abdominal organs can migrate into chest cavity 13 Is the injury thoracic or abdominal??? Trauma below the nipples (T4 or 4th intercostal space (ICS) can cause both intrathoracic and intra-abdominal injuries 14 Did you know??? The adult thoracic cavity can hold up to 3 L of blood for each side What is the average adult blood volume? 5.5 – 6.5 liters (or quarts) 1 liter = 1 quart Approximately 1.3 gallons Formula: 0.07 x weight in kg=liters of blood Ex: adult 0.07 x 80kg = 5.6 L Ex: newborn 0.07 x 3kg = 0.2 L (200ml) 15 Pleural Space A small area between 2 layers of pleura Normally filled with minimal fluid Can potentially expand if filled with air or blood Expansion is at the sacrifice of other organs in the area Visceral pleura Directly lines lungs Parietal pleura Inner lining of the chest wall 16 Mediastinum Midline area of the thoracic cavity Contains Heart Aorta and pulmonary artery Superior and inferior vena cavas Trachea Major bronchi Esophagus 17 Mechanisms of Injury Thoracic cage injuries can result from a variety of sources MVC Motorcycle incidents Falls Crush Blunt Penetrating – firearms, knives 18 MOI Blunt trauma Injuries more predictable Penetrating injuries Unpredictable organ injury Path of destruction can vary widely 19 Major Signs/Symptoms of Chest Injuries Shortness of breath Chest pain Contusions Open wounds Sub Q emphysema Hemoptysis Distended neck veins Tracheal deviation Cyanosis Shock Tenderness Instability Crepitation Altered breath sounds Asymmetrical chest movement including paradoxical motion 20 Patient Assessment Starts with scene size-up – safety a concern Primary assessment performed Remember: ABC assessment repeated any time there is a change in patient condition Moves into history taking with secondary assessment EMS patients rarely have just one isolated injury with traumatic MOI Signs and symptoms blur when injuries are mixed together 21 Airway Obstruction Results in hypoxia Tissue insult occurs quickly Once cells die, they are gone Primary assessment starts with the question: Is the airway open and do I need to apply manual c-spine control??? If the airway is not open, what do I need to do to open it??? 22 Opening a Blocked Airway If traumatic injury is suspected Modified jaw thrust In absence of trauma Head tilt/chin lift Are secretions present? Limit suctioning generally to <10 seconds Are adjuncts required? Is there a gag reflex? If necessary, stroke eyelashes to check for blink reflex- if absent, then gag reflex is absent 23 Airway Maneuvers Modified jaw thrust Used in presence of suspected or known trauma Head tilt/chin lift Used when no trauma suspected 24 Interventions for Obstructed Airways Used by EMS Cricothyroid membrane - Need to know landmarks now – patient can’t wait for you to look them up! 25 QuickTrach Device sized for adult (4.0 mm) or peds (2.0 mm) Kit contains items noted to the right Need to add skin prep material and BVM 26 Adjuncts for Obstructed Airway QuickTrach – emergency cricothyrotomy 1 person assembles equipment 1 person locates and palpates cricothyroid membrane Runs finger up from sternal notch Cricoid cartilage first rigid ring palpated Membrane is above the cricoid cartilage Skin prepped Needle inserted at 90 degree angle Air aspirated to confirm needle entry into trachea 27 Quicktrach cont’d Angle of insertion changed to 600 sliding catheter sheath forward until red stopper is flush with skin Red stopper removed Needle & syringe held firmly and plastic cannula slid forward til hub of catheter snug to skin Needle and syringe removed Patient ventilated via BVM – equipment held securely Placement assessed – BS, chest rise & fall Catheter secured with ties provided 28 Needle Cricothyrotomy Provides emergency access to an otherwise blocked airway 29 Needle Cricothyrotomy Cricothyroid membrane located Site prepped Large gauge catheter with syringe attached inserted into trachea – midline 450 angle Aspiration of air with syringe confirms placement Catheter advanced while withdrawing stylet 3.0 mm ETT hub attached to needle Ventilated with BVM via the 3.0 mm ETT hub Assessed for BS and chest rise Catheter secured Note: Will need to allow extra time for exhalation 30 Flail Chest Fracture of 3 or more (2 or more in some sources) adjacent ribs in 2 or more places each Section becomes free floating Be suspicious for the presence of pulmonary contusions It takes tremendous force to break that many ribs Organs under the rib cage most likely traumatized Compromise to normal diffusion of O2 and CO2 is usually present Flail chest does NOT automatically equal the presence of a tension pneumothorax 31 Flail Chest Can be suspicious of condition during the primary assessment Patient states “I can’t breathe” The rib fractures cause significant pain as the patient tries to take any breaths Patient is anxious May see paradoxical motion on visual inspection This is often a later sign due to initial splinting 32 Flail Chest and Primary Assessment Primary assessment DOES NOT stop Note made to go back to address why there is respiratory distress Remember: the only 2 times to interrupt a primary assessment is to (1) correct an obstructed/closed airway or to (2) control major hemorrhage 33 Flail Chest Tremendous force to fracture this many ribs Notice how lateral the clavicular midline really is!!! Landmark essential IF patient develops a tension pneumothorax 34 Flail Chest Key Signs /Symptoms Paradoxical motion on visual inspection Potential bruising or other marks on chest wall Crepitation and tenderness on palpation Decreased breath sound depending on degree of injury, splinting and presence of pneumothorax 35 Flail Chest 36 Flail Chest Treatment Supplemental oxygen therapy Non-rebreather O2 if intubation not needed Cardiac monitoring Potential high for cardiac contusion Stabilizing the chest wall is controversial Chest wall no longer taped for support Providing positive pressure ventilation (i.e.: intubation on a ventilator) is the preferred method of support which can be done in the ED if not necessary in the field) 37 Open/Sucking Chest Wound Air allowed to enter the thoracic space due to an opening in the chest wall Results from penetrating trauma Air drawn into pleural space Air will enter via the largest opening The hole created in the chest wall versus the glottic opening Air entering the pleural space does not reach the alveoli 38 Open/Sucking Chest Wound Visual inspection reveals a wound May hear a sucking or bubbling sound May feel subcutaneous emphysema around the area Lightly palpate the area and feel a crackling sensation under your finger tips Noticed skin “puffed up” 39 Open/Sucking Chest Wound Immediate treatment as soon as the wound is found is to cover the wound with a gloved hand Then place an occlusive dressing over the site Secure occlusive dressing on 3 sides Leaves a means of escape of air on the 4th side to avoid the potential of converting the injury to a tension pneumothorax If wound is large, try defib pad over wound 40 Open/Sucking Chest Wound Question If the patient develops a tension pneumothorax after a sucking chest wound is sealed with an occlusive dressing, do you need to perform a needle decompression? NO!!! – not usually There is already a BIG hole in the chest wall that air can escape from Just lift a corner of the dressing during exhalation for air to escape If there is no improvement, you might have to decompress with a needle 41 You Evaluate… What’s right? Wound immediately covered with hand What’s wrong? The care provider has no gloves on 42 Tension Pneumothorax A pneumothorax that generates and maintains pressures greater than atmospheric pressure in the thorax A one way valve is created and air flows into the pleural space and cannot escape Most often associated with a traumatic event but can be spontaneous Can be a complication of treatment of an open/sucking chest wound 43 Tension Pneumothorax – Cascade of Events A Air enters pleural space intrapleural pressure collapses lung, intercostal bulging occurs, pressure exerted against mediastinum Uninjured lung becomes compressed Vena cava compression venous return Cardiac output (CO) causing pulse; B/P JVD present, narrowed pulse pressure Tracheal shift is a late but rare sign (hard to view) 44 X-ray - Tension Pneumothorax What’s wrong with this x-ray? It should never have been taken! Diagnosis is clinical Arrow points to completely collapsed lung Dark filled images indicate air filled spaces Note tracheal shift to the right 45 Tension Pneumothorax Typical signs and symptoms Severe dyspnea Hyperinflation of affected side Diminished, then absent breath sound Hyperresonance of affected side Diaphoresis Cyanosis JVD Tachycardia Altered mental status Eventual hypotension 46 Simple Pneumothorax There is a difference These patient DO NOT require needle decompression May not even auscultate decreased breath sounds if collapse is small There is a clinical difference in presentation (i.e.: vital signs) from a simple to a tension pneumothorax 47 Jugular Vein Distention - JVD JVD present when venous pressures are high and blood cannot easily drain into the right atrium Typically seen with tension pneumothorax, cardiac tamponade, right sided heart failure and volume overload Most appropriately measured with patient sitting at 450 angle and evaluating right side of neck May not be possible with traumatic injury to HOB Note: Lack of JVD in supine position with physical findings may indicate hypovolemic shock 48 JVD Jugular vein is prominent if distended at a point slightly higher than 1 inch above right clavicle 49 Tension Pneumothorax Treatment Rapid recognition is key!!! Severe dyspnea Distinct signs and symptoms Needle decompression to relieve intrapleural pressures Administer supplemental O2 via NRB Equipment Longest and largest needle you have – 3 inch long and 12-14 gauge Skin prep material 50 Needle Decompression Landmarks Finding the Angle of Louis is an easier landmark than counting down rib spaces Angle of Louis 2nd ICS 51 Tension Pneumothorax Treatment Needle decompression Identify 2nd intercostal space (ICS) Find Angle of Louis Hang a Louis and slide into the 2nd ICS From Angle of Louis, slide finger tips toward armpit crease OR Palpate down from MIDDLE of clavicle to 2nd ICS Middle of clavicle more lateral than most people identify; is male nipple line Insert needle over top of rib 52 Landmarks for Needle Decompression If needle placed too low and too close to sternum, tip may end up placed in the heart 53 Needle Decompression Goal of needle decompression: Provide a “relief valve” for air under tension Do NOT need to make a flutter valve on needle Air will enter the path of least resistance (i.e.: the larger pathway) Diameter of trachea larger than a 14 G needle so air will enter via trachea into the lungs and not through a 14G needle into the pleural space 54 You Evaluate… What’s wrong? Too medial Too low, tip may be in the heart Needle should have been here X What’s right? Catheter secured 55 Pericardial/Cardiac Tamponade Blood or fluid fills the pericardial sac surrounding the heart Sac does not expand but compresses into the heart limiting flow into the heart Penetrating trauma most frequent MOI High mortality rate due to potential for rapid hemorrhage 56 Pericardial/Cardiac Tamponade Agitation Tachycardia Diaphoretic pulse strength & rate Muffled heart tones Beck’s triad (next slide) Pulsus paradoxus Systolic B/P drops by 10 mmHg on inspiration Pulsus alternans Alteration between strong and weak pulses PEA 57 Beck’s Triad Indicative of pericardial tamponade (IF present) This may be a LATE sign! A grouping of 3 clinical signs JVD Muffled/distant heart tones Hypotension 58 Pericardial/Cardiac Tamponade It takes as little as 150-300 ml to exert pressure to impede contractile function on the heart Removing as little as 20 ml may improve the contractile force to improve the patient’s condition EMS goal: RAPID IDENTIFICATION Then rapid transport There won’t be much intervention in the field that will save the patient’s life; they rapid need transport 59 Aortic Tear Most commonly from blunt trauma MOI usually high speed MVC - especially lateral impact - and falls from great heights High mortality rate – 85 - 95% GOAL: Rapid recognition of those patients that survive the initial impact Transportation to a Level I trauma center (if within 25 minutes of transport) 60 Aortic Tear Aorta fixed at 3 points in the thoracic cavity Shearing forces can separate the arterial layers of this large, high-pressured vessel Due to high pressures, aortic lining becomes a false space Rupture can occur without surgical repair Death from rupture is usually quick; dissection progresses more slowly 61 Aortic Tear Most commonly tear just past the arch of the aorta Less often at aortic root (annulus) where the aorta joins the heart and the area where aorta exits the chest at the diaphragm 62 Aortic Tear Typically patient complains of a severe tearing chest pain Pain may radiate to the back Reduced pulse strength in lower extremities Mark pulse spots if palpated Pulse deficit between left & right upper extremities If suspected, palpate to compare both radial pulses 63 NEW!!! Permissive Hypotension in Trauma Restrictive fluid therapy new concept At least until hemorrhage is controlled Highly suggested for aortic problems Not recommended in the patient without a pulse Aggressive fluid replacement tends to increase total volume of blood loss EMS may call Medical Control for guidelines if they feel patient may benefit from restricted fluid resuscitation May order trendelenberg positioning 64 Region X SOP’s - Fluid Challenge Fluid given in 200 ml INCREMENTS You assess as you go For medical calls patient more likely will tolerate and need the 20 ml/kg replacement formula Every body holds a different amount of blood volume Adult average 5.2 – 6 liters (5.5 – 6.5 quarts or 10-12 pints) FYI - Average blood donation is 450 ml This is less than 1 pint Child average 2 liters Infant average is 85 ml/kg or <300 ml 65 Blood Volume by Age Do not judge the significance of the volume you see lying in a pool until you know whose blood it is 66 How Low Can You Go? Classes of shock Class I - <15% (<750 in the adult) Class II – 15-30% (750 – 1500ml in the adult) Class III – 30-40% (1500-2000ml in the adult) Class IV - >40% (>2000ml in the adult) Compensated shock in Class I & II Decompensated shock by Class III Blood pressure falling is the key Blood pressure falling is also a LATE sign 67 Complications Related to Traumatic Injuries Goal – Do no further harm Sometimes, doing our best just isn’t enough Secondary injuries may develop based on what we do or don’t do at first patient contact It’s simple – do the right thing at the right time and document accurately 68 Complications: Crush Injuries Traumatic insults of severe compressive forces Crush injury – an injury compressing a body part If short duration, local injury confined to injured part Crush syndrome – systemic effects of entrapment if entrapment longer than 4 hours A potentially life-threatening event Limitation of effective & healthy circulation Think cave-in’s, equipment entrapment 69 Crush Syndrome Pressure remains imposed for long period of time (usually >4 hours) Traumatic rhabdomyolysis develops Crushed skeletal muscle disintegrates Release of metabolic by-products restricted to the compressed area for as long as area remains compressed Myoglobin – a muscle protein Phosphate & potassium (K+) – from cell death Lactic acid – from anaerobic metabolism 70 Crush Syndrome When pressure released, metabolic by-products enter the central circulation Cause severe metabolic acidosis Toxic to heart and kidneys Myoglobin plugs kidney’s filtering system Sodium, chloride and water flood into damaged tissue creating hypovolemia Hyperkalemia reduces cardiac muscle response to electrical stimuli dysrhythmias Aerobic process resumed producing more uric acid increasing cellular acidity and injury 71 EMS/Field Care of Crush Injuries Potential patient needs to be identified prior to extrication Scene safety is the fist priority Goal of EMS: Rapid transport Adequate fluid resuscitation Diuresis – keep kidneys flushed and working Possibly systemic alkalinization Corrects acidosis, hyperkalemia, prevents renal failure Hospital may need to send a team with meds like 72 sodium bicarbonate EMS Care cont’d Cardiac monitoring Influence of potassium and lactate traveling to heart may cause dysrhythmias Tenting or peaking of T wave Prolonged PR interval ST segment depression Widening QRS (high levels of K+) Note: Cardiac monitor should be applied prior to releasing the crushed area from entrapment Rapid onset of shock after release from entrapment may develop 73 Tall, Peaked T wave Indicates excess potassium circulating in the bloodstream Normal potassium levels 3.5 – 5 meq/L Hyperkalemia (>5.5 meq/L) is a cardiac irritant 74 Compartment Syndrome Complication most commonly associated with closed injuries to the extremities Think of the patient who has fallen and is in one position for a period of time before a wellbeing check finds them Major muscle groups contained in compartments Swelling of muscles will impede blood flow to nerves, blood vessels and other structures Most common site are lower extremities 75 Compartment Syndrome Six P’s Pain out of proportion – key finding!!! Pallor Paralysis Paresthesia – pins & needles tingling Pressure – feeling tension in extremity Pulses – diminished or absent Signs & symptoms not dependable 76 Compartment Syndrome Difficult to assess Motor and sensory usually intact Distal pulses often present Capillary refill with little to no change More likely to develop beyond 6-8 hours post-injury or even later Key: patient complaining of pain out of proportion Don’t assume they are a wimp 77 EMS/Field Care of Compartment Syndrome Maintain high index of suspicion Elevation single most important tool for EMS Reduces edema Increases venous return Lowers compartment pressure Helps prevent ischemia Cold pack applied to severe contusions Hospital care includes measuring pressures Normal pressure near zero Pressure >30mmHg restricts capillary flow Irreversible ischemic changes after 10 hours 78 Hospital Intervention Compartment Syndrome Fasciotomy is surgical intervention to open fascia to allow for swelling without restrictive pressures When pressures go down, patient taken back to surgery to close the wound left open 79 Transport Criteria Highest level Trauma Center within 25 minutes Unstable per vital signs Anatomy of injury – life threatening injury Closest Trauma Center Based on mechanism of injury with higher potential for traumatic injury or traumatic arrest Patient is stable Patient may have co-morbidity increasing their risk level with the insult Closest appropriate comprehensive ED Do not meet any of the above criteria or EMS unable to 80 establish an airway Case Scenarios Review the following cases What is your general impression? Review steps of the primary assessment Is there a life threatening condition? What are appropriate EMS interventions and when are they performed? Where does this patient get transported to? 81 Case Scenario #1 EMS responds to a call for MVC – 2 vehicles One patient is a 16 y/o female restrained driver hit head-on approximately 45 mph by a Suburban This is seen as EMS approaches the scene 82 Case Scenario #1 + seatbelt Airbag deployed Small staring at base of windshield Driver’s side window shattered; unable to open door A & O x3; hysterical teenager Active bleeding from nose Multiple lacerations to face and extremities 83 Case Scenario #1 Primary assessment Mental – Patient awake, A & O x3, hysterical Airway – open C-spine – manual control taken Breathing – rapid, without effort Circulation – bleeding from nose; pulse rapid and regular Life threats identified? None So EMS keeps moving on the survey and keeps looking for injuries 84 Case Scenario #1 If this patient had chest injuries, what clues would indicate: Flail chest Multiple rib fractures found on palpation Pain with breathing Pneumothorax Pain with breathing Decreased or absent breath sounds Tension pneumothorax Agitation, tachycardia, hypotension, absent BS 85 Case Scenario #1 – EMS Care – What Intervention Would Be Done? Flail chest Supplemental O2 BVM for positive pressure ventilation if severe Pneumothorax Supplemental O2 Observed for development of tension pneumothorax Tension pneumothorax Needle decompression 2nd ICS Needle placed above the rib Avoids nerves and blood vessels that run on inferior surface 86 Scenario #2 EMS has been called to the scene of a MVC No witnesses Passer-by noticed MVC and called it in Patient has an altered level of consciousness What are the components of a primary assessment? Mental status ABC’s with c-spine Identification of life threats These can be applied to the walk-in to the ED! 87 Scenario #2 The scene is safe The patient is in the red car They are looking around upon your arrival They do not follow commands They are confused Immediate control of the c-spine is taken 88 Scenario #2 Patient is wearing a seat belt Witnesses state the patient did not slow down but just ran into the car in front of them Airway – open Breathing – rapid, regular Circulation – clammy, pale, pulse regular and fast No obvious bleeding 89 Scenario #2 No life threats are found Why would the patient be confused??? Head injury? Alcohol, drugs? Hypoglycemia? Blood sugar checked – 35 Treatment indicated? IV access established D50 administered 90 Scenario #2 IV infiltrates while pushing D50 Now what??? Infusion stopped IV line D/C’d Event documented Verbal report given to ED 91 Extravasation of IVP Dextrose Carefully monitor the site as medication is given IVP 92 Case Scenario #3 Female driver in small car had tree fall on her car during a rain storm Patient impaled with branch of tree Are these chest or abdominal wounds? Could be both depending on inhalation or exhalation at time of injury and path of FB 93 Case Scenario #3 How does EMS care for the open wound in the field? Moist sterile saline dressing over the open tissue Covered with dry dressings Avoid poking anything into the wound Observe for evisceration 94 Case Scenario #3 – Pain Management per Region X SOP Fentanyl 0.5 mcg/kg IVP/IN/IO May repeat in 5 minutes with same dose Max total 200 mcg Same formula for adult and peds Less cardiovascular changes than morphine Less nausea from the medication As a synthetic narcotic, still watch for respiratory depression 95 Case Scenario #3 Tree branch removed from patient 96 Case Scenario #4 Patient fell onto bicycle Patient agitated, complains of inability to breath breath sounds unilaterally Patient is dyspneic, tachycardiac, becoming cyanotic, with JVD increasing Blood pressure falling (radial pulse harder to palpate) What’s your impression? Tension pneumothorax 97 Case Scenario #4 What intervention is necessary? Immediate needle decompression What are the landmarks? 2nd ICS Midclavicular line Stay more lateral than you think 98 Needle Decompression 2nd ICS, midclavicular line – “X” marks the spot When needle inserted, listen for hiss of released air Should have immediate improvement in patient X 99 Steps for Needle Decompression Find the Angle of Louis Fingers slid toward the armpit crease Stop at the midpoint of the clavicle This is in-line (vertical) with the male nipple The male nipple horizontally lies in the 4th ICS Needle inserted above the rib, advance and begin to separate needle from catheter Secure in place 100 Needle Decompression Needle inserted above the rib Avoids puncturing the vessels or nerves Takes time for lungs to re-expand Do not expect instantaneous breath sounds to reappear 101 Bibliography Region X Advanced Life Support Standard Operating Procedures February 1, 2012 Bledsoe, B., Porter, R., Cherry, R. Paramedic Care Principles & Practices Fourth Edition. Brady. 2013. Campbell, J. International Trauma Life Support for Emergency Care Providers. 7th edition. Pearson. 2012. Caroline, N., Emergency Care in the Streets. 7th Edition. AAOS. 2013. Limmer, D., O’Keefe, M. Emergency Care 12th Edition. Brady. 2012. http://en.wikipedia.org/wiki/Beck's_triad_(cardiology) http://docpods.com/compartment-syndrome-in-the-lowerleg 102