Download
trauma iii n.
Skip this Video
Loading SlideShow in 5 Seconds..
TRAUMA III PowerPoint Presentation

TRAUMA III

184 Views Download Presentation
Download Presentation

TRAUMA III

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. TRAUMA III Effects of heat, cold, electric shock, drowing, wounds and bleeding, dressing and bandages

  2. EFFECTS OF HEAT

  3. Regulation of body temperature • Normal body temperature • Heat production • Heat loss

  4. Body Heat Production • Basal energy metabolism (adults) • 65 to 85 Kcal/hr or 50 to 60 Kcal/hr/m2 body surface area • 1/2 of body heat generated by the liver, heart and brain • At rest, muscle contributes 25 % • Exposure to cold leads to increase in muscle tone which increases body heat production by 50 to 100 % • Shivering increases body heat production 400 %

  5. Mechanisms of Heat Loss • Conduction (2 %) • Transfer of heat by direct physical contact • Convection (1 to 40 %, depends on wind velocity) • Transfer of heat to air / water vapor circulating around body • Radiation (30 to 65 %) • Heat transfer by infrared waves • Evaporation (10 to 80 %) • Conversion of liquid sweat to vapor (0.58 Kcal / cc of H2O evaporated) • Breathing

  6. Predisposing Factors to Heat-Related Illness • Exogenous heat gain • Endogenous heat gain • Impaired heat dissipation

  7. Sources of Exogenous Heat Gain • Closed spaces (locked cars, etc.) • Bright sunshine (150 Kcal / hr) • Lack of air conditioning • Hot soil (can transmit heat through shoes)

  8. Sources of Endogenous Heat Gain • Exercise (300 to 900 Kcal / hr) • Agitation • Fever / infection • Hypermetabolism / hyperthyroidism

  9. Causes of Impaired Heat Dissipation • High environmental temperature • High environmental humidity • Lack of acclimatization • Excessive clothing • Obesity • Diabetes / autonomic neuropathy • Sweat gland dysfunction (dehydration, cystic fibrosis, ectodermal dysplasia, scleroderma, extensive scars) • Previous heatstroke

  10. FORMS OF HEAT ILLNESS • Mild forms of heat illness : • Heat edema • Heat cramps • Heat syncope • Prickly heat • Heat Exhaustion : • Sodium depletion type • Water depletion type • Heatstroke : • Classic • Exertional

  11. Treatment of Mild Forms ofHeat Illness • Heat edema (usually only hands, feet, ankles) • Elevation, support hose (do not use diuretics) • Heat cramps (due to Na depletion) • Cooling, PO fluids containing some salt • Heat syncope (usually due to mild fluid depletion) • Rest, PO fluids • Prickly heat • Skin cleansing, loose clothing, antibiotics if pustular

  12. Heat Exhaustion:Sodium Depletion Type • Etiology • Usually in unacclimatized • Usually young age • Exercise in hot environment • Mildly inadequate fluid intake & moderate inadequate Na intake • Signs: febrile, headache, weakness, fatigue, nausea, diarrhea, cramps, hypotension / tachycardia • treatment: Rest, cooling, fluids (PO or IV) with sodium

  13. Heat Exhaustion : Water Depletion Type • Etiology: Usually elderly with inadequate free water intake ; can lead to heatstroke • Signs: Febrile, thirst, weakness, confusion • Treatment: Cooling, rest, hypotonic fluids ; if elderly, may need hospital admission

  14. Heatstroke : Items Required for Diagnosis • Exposure to heat stress : internal or external • Elevated body temperature (usually > 40 C) • Major CNS dysfunction (bizarre behavior, seizures, coma, etc.) • Usually tachypneic, tachycardic, hypotensive • Usually anhydratic

  15. Heatstroke • A true emergency • Two types : • Classic (Usually elderly,occurs after exposure to heat for > 1 week, mortality 70 % untreated, 10 to 20 % treated) • Exertional (Usually younger age, usually after heavy exertion, may still have sweating, may have rhabdomyolysis / renal failure, mortality 30 % untreated, < 10 % treated

  16. Heatstroke : Emergency Treatment Protocol • Airway management : intubate if comatose ; High flow O2 for all • Large bore IV and rapid bolus 500 to 1000 cc NS • Draw blood (CBC, lytes, BUN, glucose, creatinine, PT, PTT, platelets, lactate, calcium, LFT's, CPK, ABG) • Rapid external cooling : fully undress patient, ice bath or cool skin soaks and fans • Foley and NG tube insertion : iced NG lavage

  17. Heatstroke : Emergency Treatment Protocol(cont.) • Monitor core temp. (high rectal probe or esophageal) ; stop external cooling when core temp. < 39O C • Monitor for hypotension, hypocalcemia, arrhythmias, seizures, acidosis, ARF • Admit to ICU • Acetaminophen (do not use aspirin) • Consider low dose phenothiazine (chlorpromazine 25 mg IV) or diazepam IV to promote heat loss and lessen shivering

  18. Heat Illness : Prevention • Time exertion to avoid sunlight exposure and the hottest daytime hours (10:00 am to 3:00 pm) • Light loose clothing permitting airflow over body surface • Consume 400 to 500 cc fluid before exertion and 200 to 300 cc at 20 min. intervals during exertion • Check body weight before practice : if wt. down 3 % , increase PO fluids ; if wt. down 5 %, cancel participation that day ; if wt. down 7 %, immediate fluids & consider medical attention • Use only low osmolal fluids (< 2.5 g glucose and < 0.2 g NaCl per 100 cc) • Extra NaCl and potassium intake during acclimatization

  19. EFFECTS OF COLD

  20. Hypothermia – general effect of cold • Definition : • Body temperature < 35 degrees C (95 F) • Severe hypothermia : • Body temperature < 28 C

  21. Signs and symptoms • Shiverings • Amnesia • Poor muscular coordination • Stupor • Irregular heart rythms • Loss of consciousness • Pupils dilate • Unresponsivness • Hypoternsion • Hypoventilation

  22. Hypothermia : Neurologic Effects • Cerebral blood flow decreased by 6 to 7 % for each 1° C decrease in core temperature • May cause fatigue / confusion : "paradoxical undressing" • EEG flat line below 200C (68 0F)

  23. Hypothermia : Typical Cardiac Rhythms Rhythms Sinus tachycardia Sinus bradycardia Atrial fibrillation Ventricular fibrillation Asystole Temp. (˚C) 33 to 36 32 to 35 28 to 32 < 28 < 26

  24. Conditions Predisposing to Hypothermia • Shock • AMI / CHF • Hemorrhage • Malnutrition • 6. Drugs • Any CNS depressant • ETOH • Dermal diseases • Paget's disease • Infections • 10. Pancreatitis • Extremes of age 2. Metabolic diseases • Hypothyroidism • Diabetes • Renal failure • Hypoadrenalism 3. CNS diseases • Cerebrovascular disease • Any degenerative CNS disease • Head trauma • Parkinson's

  25. Factors That Predispose to Cold Injuries FactorMechanism Wind Increase heat loss Moisture Inadequate clothing Alcohol consumption Increased heat loss, Fatigue impaired judgment Injury Increased heat loss Loss of consciousness Tobacco use Diminished peripheral Constricting garments blood supply High altitude Hypoxia

  26. Causes of Vulnerability to Hypothermiaby the Elderly • Lack of ability to shiver • Thinner epidermis; less effective insulator • Lack of cardiovascular reserve for compensation • Tendency toward baseline dehydration • Movement impairment • Effects of concurrent medications

  27. Hypothermia in Trauma Patients • If occurs, shown to increase mortality compared to that expected from their Injury Severity Score (ISS) • Can occur in just a few minutes after E.D. arrival • Exacerbated by soak dressings for burns or wounds • Often first manifested by sudden coagulopathy & capillary bleeding • Always should not just measure temp. early, but also continue to monitor core temp. • Can cause "masking" of pain from injuries

  28. GOALS OF PREHOSPITAL TREATMNET • Reduce further heat loss • Avoid ventricular arrhythmias-gentle handling of patient • Modification of CPR • Restricted passive rewarming techniques

  29. Hypothermia : Field Care • Core Temperature < 28 0 C • Hold CPR if : • No monitor available • Any patient movement observed • Respiratory rate 4 to 6 breaths / min. • Sinus bradycardia or atrial fib on monitor • Pulse present (even if slow) • CPR if : • VF or asystole on monitor • Arrested and only mild hypothermia (320to 350C) • IV Glucose or checking dextrostick should be routine (+/- naloxone)

  30. Hypothermia : Rewarming • Objective of rewarming : • Core temperature rise > 1 C per hour • If this cannot be achieved, then either more aggressive rewarming measures need to be done, or the patient is dead & unresuscitatible • Core Rewarming Techniques • Warmed O2 (420C) by FM or ETT • Warmed IV fluid (420C ) • Nasogastric tube lavage • Rectal tube lavage • Peritoneal dialysis catheter lavage • Chest tube lavage • Thoracotomy / mediastinal lavage • Cardiopulmonary bypass (fem-fem)

  31. Hypothermia : External Rewarming Techniques • Warm blankets ; cover scalp • Warm environment (heat the room or ambulance) • Warm water bath • Axillary / groin hot packs

  32. Disadvantages of Active External Rewarming asSole Rewarming Technique • May cause : • Core temp. "afterdrop" • May result in V-fib • Hypotension / cardiovascular collapse from peripheral vasodilatation • Increased hypoxia & acidosis if peripheral metabolism increases but the "cold" heart not yet able to compensate

  33. Prevention of Hypothermia in TraumaPatients • Warm the trauma resuscitation room • Should have separate thermostat from rest of E.D. • Limit personnel traffic in & out of room • Heating lamps • Heating blanket • Have in place before patient placed on stretcher • Warm all IV fluids & blood • Cover patient's scalp once it is examined • Maintain coverage of patient's body with blankets once exam is complete

  34. General Prevention Measures for ExposureHypothermia • Adequate clothing in layers • Cover scalp • Avoid alcohol / sedatives • Limit wind exposure • Maintain fluid intake • Change wet clothes promptly • If getting wet is unavoidable, use wool garments (wool maintains insulation effect even when wet, unlike cotton) • Trip planning • If immersed in cold water, extend survival time by remaining still, huddling in group

  35. Local cold injuries • Frostbite –freezing cold injury • Nonfreezing cold injury • Trenchfoot (immersion foot) : due to exposure to wet cold for 1 to 2 days; causes skin damage like partial thickness burns ; deep damage rare • Chilblain (pernio) : due to prolonged exposure of limb to dry cold : small painful ulcers over exposed areas • Frostnip

  36. Frostbite : Pathophysiology • Extracellular ice formation • Intracellular ice formation • Cell dehydration and shrinkage • Abnormal intracellular electrolytes • Thermal shock • Lipid-protein denaturation

  37. Frostbite : Two Types • Superficial : • skin is cold, pale, gray, bloodless, but pliable and soft beneath the surface • 24 hours : large clear blisters • 2 to 7 days : skin blackens, demarcates (dry gangrene) • Several months : peels off, revealing sensitive new skin • Deep : • tissue feels woody or stony • May include muscle, bone or tendon necrosis • Distal portions remain cold and cyanotic after rewarming • Risk of rhabdomyolysis • Can diagnose these only prior to thawing

  38. Frostbite : Clinical Presentation • First degree • Erythema, yellowish plaque • Second degree • Skin vesicles filled with clear or milky fluid • Third degree • Skin vesicles filled with bloody fluid • Fourth degree • Injury across dermis ; dysfunction and damage of deep structures

  39. Frostbite : Treatment • Rapid rewarming in 420 C water (do not thaw in field if refreezing might occur) • Narcotics • Tetanus prophylaxis • Topical antibiotics as for 2nd degree burns • No debridement surgery for at least several months unless wet gangrene / infection occur • If large amounts of tissue involved, watch for rhabdomyolysis / renal failure

  40. EFFECTS OF ELECTRIC SHOCK

  41. Electrical Current Flow Effecton Humans • Alternating current has a tetanizing effect on muscles • "Let-go current" (the current level at which the person is unable to release his grasp on the conductor) is 15 milliamps for men & 10 milliamps for women • Strong sustained muscle contraction can cause fractures • Can induce ventricular fibrrilation • Direct current (DC) felt as heat only & can cause a single violent muscle contraction that can throw the victim from the power source

  42. High Voltage Electrical Injuries: Pathology • Causes coagulation necrosis of tissue along current path • Points of maximum destruction are at skin entrance and exit sites • May cause extensive muscle necrosis in limb or trunk beneath unburned skin • May cause myocardial necrosis, peripheral nerve injuries, bowel wall necrosis • Retrograde amnesia / confusion for several days common

  43. High Voltage Electrical Injury: Complications • Acute MI / arrhythmias • Respiratory arrest • Renal failure • This is really an iatrogenic problem & should be preventable if sufficient resuscitation fluid is given • Infections / sepsis • Peripheral neuropathy • Amputations • Cataracts

  44. Lightning Injury : Types • Direct strike • High morbidity (since head is hit) • Splash current • On outside of body • Causes flame-like burns • Ground current • May cause mass casualities from one strike • Arrhythmias or asystole predominate

  45. Lightning Injury : Skin Injuries • "Feathering" • Very common • Is superficial fern-like marks • Not a true skin burn • Disappear after a few days • 2nd or 3rd degree burns • Usually due to clothing fire or contact with heated metal

  46. Lightning Injury : Cardiac Effects • Depolarizes entire myocardium at once • Single systolic contraction ; leads to asystole • Then return of cardiac function (bradycardia) • If apnea however, leads to hypoxia, then ventricular fibrillation • May show EKG changes -acute MI without coronary artery occlusion • May have vasomotor spasm & prolonged arterial vasoconstriction

  47. Lightning Injury : Neurologic Effects • Loss of consciousness : 72 % of cases • Paralysis of respiratory center ; leads to apnea • Rarely : rapid cerebral edema and even brainstem herniation • Transient motor paralysis : 70 % • Mechanical trauma : skull fracture, intracranial hematomas

  48. Assessment and treatment • Ensure your safety (confirm that the electric power is off) • Perform ABC control - CPR if necessary. • Be carefull of any fractures (cervical spine!) • Assess and dress wounds, burns.

  49. DROWING

  50. Drowning : Definitions • Drowning : death by suffocation after submersion in a liquid (pt. dies within 24 hours of submersion) • Near drowning : survival (short or long term) following asphyxia secondary to submersion • Secondary drowning (or delayed drowning or postimmersion syndrome) : death more than 24 hours post submersion from complications related to submersion (pulmonary injury, sepsis, renal failure, etc.)