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Definition. Circulatory system failure to supply oxygen and nutrients to meet cellular metabolic demands . Shock. Classification and causes: Hypovolemic Distributive Cardiogenic Obstructive dissociative. Hemodynamics. Textbook of Pediatric Advanced Life Support, 1988.
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Definition Circulatory system failure to supply oxygen and nutrients to meet cellular metabolic demands .
Shock Classification and causes: Hypovolemic Distributive Cardiogenic Obstructive dissociative
Hemodynamics Textbook of Pediatric Advanced Life Support, 1988
Cardiovascular function Cardiac Output CO = HR x SV HR responds the quickest SV is a function of three variables : preload, After load, myocardial contractility A noncompliant heart cannot increase SV
Cardiovascular function 1-Cardiac Output 2-Clinical Assessment peripheral perfusion Temperature capillary refill urine output Mentation acid-base status
Hypovolemic shock Definition: • Decreased circulating blood volume. • Common causes: • Hemorrhage • Diarrhea • Diabetes insipidus • Diabetes mellitus • Burns • Adrenogenital syndrome
Distributive shock Definition Vasodilation and decreased preload Common causes: Sepsis Anaphylaxis Spinal injury Drug intoxication
Cardiogenic shock • Decreased myocardial contractility • Common causes: • Congenital heart disease • Severe heart failure • Arrhythmia • hypoxic ischemic injuries • Cardiomyopathy • Myocarditis • Drug intoxication • kawasaki
Obstructive shock Definition Mechanicalobstruction to ventricular outflow. Common causes: • Cardaic tamponade • Massive pulmonary embolus • Tension pneumothorax • Cardiac tumor
Dissociative shock Definition • Oxygen not released from hemoglobin. • Common causes • Carbon monoxide poisoning • methemoglobinemia
Organ directed therapeutics • Cardiovascular support • Fluid resuscitation • Cardiotonic and vasodilator therapy • Respiratory support • Renal salvage
Cardiovascular Changes in Shock Type Preload Afterload Contractility Cardiogenic Hypovolemic No change Distributive Septic early late
Evaluation • Regardless of the cause: ABC • First assess airway patency • ventilation • then circulatory system
Evaluation • Respiratory Performance • Respiratory rate and pattern • work of breathing • oxygenation (color) • level of alertness • Circulation • Heart rate, BP, perfusion, and pulses, liver size • CVP monitoring may be helpful
Evaluation • Early Signs of Shock • sinus tachycardia. • delayed capillary refill. • fussy, irritable. • Late Signs of Shock
Evaluation • Late Signs of Shock • bradycardia • altered mental status (lethargy, coma) • hypotonia, decreased DTR’s • Cheyne-Stokes breathing • hypotension is a very late sign
Cardiovascular Assessment (con) • CNS Perfusion • Recognition of parents • Reaction to pain • Muscle tone • Pupil size • Renal Perfusion • UOP >1cc/kg/hr
Cardiovascular Assessment (con) • Skin Perfusion • Capillary refill time • Temperature • Color • Mottling
Therapy for shock • The key therapy is the recognition of shock in its early state. • Treating the signs and symptoms. • Minimize cadiopulmonary work. • Ensuring cardiac output blood pressure and gas exchange
Hypovolemic Shock • Mainstay of therapy is fluid . • Goals: • Restore intravascular volume • Correct metabolic acidosis • Treat the cause
Hypovolemic Shock (treatment) • Degree of dehydration often underestimated • Reassess perfusion, urine output, vital signs... • Isotonic crystalloid is always a good choice • 20 to 50 cc/kg rapidly if cardiac function is normal • NS can cause a hyperchloremic acidosis
Other Studies • Look for etiology of shock. • Evaluate hemoglobin, hematocrit, and platelet count. • Shock from any etiology can lead to DIC and end organ damage
Other Studies • CBC, PT, INR, PTT, Fibrinogen, Factor V, Factor VIII • Check LFT’s, follow CNS and pulmonary status
Conclusion • Goal of therapy is; identification evaluation and treatment of shock in its earliest stage • Successful resuscitation depends on early and judicious intervention • Initial priorities are for the ABC’s
Conclusion • Fluid resuscitation begins with 20cc/kg of crystalloid or 10cc/kg of colloid • Subsequent treatment depends on the etiology of shock and the patient’s homodynamic condition
Related infection and shock • Infection • Bacteremia • Systemic inflammatory response syndrome : (2 or>2 of following) (T>38 HR>90 RR>20 WBC>12000 or<4000)
Related infection and shock • Sepsis: Systemic response to infection • Sever sepsis: sepsis + organ dysfunction (hypo perfusion, lactic acidosis, oliguria,or an acute alter mental status)
Related infection and shock • Septic shock: sepsis +hypotention despid adequate fluid • Hypotention: systolic<9 or >4reduction • Multiple organ dysfuntion
Burns • Disruption 3 key function of skin • Regulation of heat loss • presevation of body fluid • Barrier of the infection
Patophisiology • Release inflammatory and vasoactive mediators • capillary permeability increase • Decrease plasma volume and cardiac output • Shock is common if borne > 10% -12%
classification • Depth of injury • Percent of body surface area involved • Location of the burn • Association with other injuries
Clinical manifestation 1-First – degree: • Red, painful dray • Superficial and limited to epidermis. • Heal in 3-6 days
Clinical manifestation 2-Second degree: • Partial-thicking 1-superficial ( red,painful,blister) heal in 10-21 days 2-deep dermal( pale ,painful, yellow) heal in 3 weeks , scarring
Clinical manifestation 3-Third –degree: • Full thickness ,require grafts if >1 cm • Avascular and coagulation necrosis 4- fourth – degree: • Involve underling facia, muscle or bone
Clinical manifestation • Sever burn: >15%Body surface involves face or prineum 2 and 3 –degree burns hands or feet circumfrential burn of extermity inhalation injury
Percent of body surface area involved • Each upper extremity 9% • each lower extremity 18% • Posterior trunk 18% • Anterior trunh 18% • Head 9% and prinium1% Location is important : • Face, eyes, ears, feet, prinium, hand ,full thickness
treatment decision is based on : • Extent of burn(% burn) , body surface (location),type of burn, associated injure, medical complication ,availability ambulatory management • Stop the burning process • Fluid and electrolyte support (systemic copillary leak)
treatment • Significant burn , Second 24 hr dextrose in0.25 normal bolus 20cc/kg lactated Ringer • Total fluid is 2-4cc/kg/percent burn/24 hr (Half in first 8 hr) that equal 1cc/kg/hr of urine saline • Colloid therapy is needed if burn >30% bs and provided after 24 hr with crystalloid
treatment • Nutritional support: ( burn produce hypermetabolic response that sedation and analgesic can decrease) In critical burn parenteral nutrition Enteral feeding résumé on 2-3 days
treatment • Wound care: • Relief any pressure on cerculation • Covered with sulfadiazin • Graft • Tetanus toxoid in incomplete immunization
hospitalization • Extended of burn > 10% in children • Body surface area involved: Face ,neck, both hands, both feet ,prineum • Type of burn; electrical contact ,chemical • Association injuries; Soft tissue trauma, fractures,smoke inhalation head injury .
hospitalization • Complicating medical problems Diabetes ,heart disease, pulmonary disease, ulcer history. • Social problem. Suspected child abuse or neglect, self infected burn, psycologic problems
Burn Complication • Sepsis ( avoid prophylactic antibiotic) • Hypovolemia, hypothermia • laryngeal edema • carbon monoxide injury (100% o2,hyper baric o2) • cardic disfunction • gasteric ulcer
Burn Complication • compartment syndrome • contracture • hyper metabolic state • renal failure • anemia • psychological trauma • pulmonary infiltration,pulmonary edema, pneumonia,bronchospasm