1. MANAGEMENT OF SHOCK

2. DEFINITION OF SHOCK Shock is a systemic state of low tissue perfusion, which is inadequate for normal cellular respiration. Shock is not synonymous to hypotension. 3. PATHOPHYSIOLOGY OF SHOCK Cellular Micro vascular Systemic -Cardiovascular -Respiratory -Renal -Endocrine 4. Stages of Shock A progressive process: Intervene early Compensated Shock (nonprogressive stage) Cardiac output (HR x SV) and systemic vascular resistance (peripheral vasoconstriction) work to keep BP within normal by reflex compensatory mechanism. On exam: Tachycardia; decreased pulses & cool extremities in cold shock; flushing and bounding pulses in warm shock; oliguria; labs may show mild lactic acidosis 5. Stages of shock . . . Progressive(Uncompensated)stage : Compensatory mechanisms are overwhelmed. Widespread hypoxia. Hypotensive shock. On exam: As above, plus hypotension, altered mental status; decreased urine output, labs may show increased lactic acidosis Generally quick progression to cardiac arrest. 6. Stages of shock . . . Irreversible stage : Widespread cellular injury. Release of lysosomal enzymes, worsened cardiac contractility. Irreversible organ damage, death. 7. CLASSIFICATION OF SHOCK A- Classification of Shock by Causes (1) Hypovolemic shock Loss of fluid (2) Cardiogenic shock Pump failure (3)Distributive shock - Neurogenic shock -Anaphylactic shock IgE mediated - Septic shock Sepsis 8. B. Classification of Shock according to hemodynamic changes: Hypodynamic Shock: Cardiac Output , Vascular Resistace, Cold Skin; Hyperdynamic Shock: Cardiac Output , Vascular Resistace , Warm Skin; 9. HYPOVOLEMIC SHOCK 10. Non-hemorrhagic Vomiting Diarrhea Bowel obstruction, pancreatitis Burns Neglect, environmental (dehydration) Hemorrhagic GI bleed Trauma Massive hemoptysis AAA rupture Ectopic pregnancy, post-partum bleeding Hypovolemic Shock 11. Signs & Symptoms: Hypotension, Tachycardia, , Oliguria, Diminished Pulses. Markers: monitor urine output (UOP), central venous pressure (CVP), blood pressure(BP), heart rate(HR), hematocrit(Hct), mental state(MS), cardiac output(CO), lactic acid and pulmonary capillary wedge pressure(PCWP) 12. Classes of acute hemorrhage Class I Class II Class III Class IV Blood loss < 750 cc 0- 15% 750-1500 15-30% 1500-2000 30-40% >2000cc >40% HR Normal PP Normal BP Normal Normal UOP Normal Normal Decreased Negligible Mental Normal Anxious Confused Lethargic Fluid Crystalloid Crystalloid Crys+blood Crys+blood *ATLS; 2004. 70kg male 13. CARDIOGENIC SHOCK Causes: 1.Cardiomyopathies: myocardial ischemia, myocardial infarction, cardiomyopathy, myocardiditis, myocardial contusion 2.Mechanical: cardiac valvular insufficiency, papillary muscle rupture, septal defects, aortic stenosis 14. 3- Arrythmias: bradyarrythmias (heart block), tachyarrythmias (atrial fibrillation, atrial flutter, ventricular fibrillation) 4- Obstructive disorders: pulmonary embolism PE, tension peneumothorax, pericardial tamponade, constrictive pericaditis, severe pulmonary hypertension 15. Signs and symptoms : Dyspnea, gallop, low BP, oliguria Monitor/findings: CXR pulmonary venous congestion, elevated CVP, Low CO. 16. SEPTIC SHOCK This type of shock is due to infection/sepsis. Any focus of infection can cause infection. -Gastrointestinal -Genitourinary -oral -skin. 17. Pathogenesis of Sepsis 18. Systemic Inflammatory Response Syndrome (SIRS) Systemic inflammatory response to a variety of severe clinical insults manifested by 2 or more of the following conditions Temperature >38.5C or 90 beats/min Respiratory rate >20 breaths/min or PaCO2, wide pulse pressure COLD SHOCK Hypotension Cold clammy skin Mottling Tachycardia Cyanosis Narrow pulse pressure acidosis 21. Signs: Early warm with vasodilation (hyper dynamic circulation), often adequate urine output, fever and tachypnea. Late-- vasoconstriction, (hypodynamic circulation). hypotension, oliguria, altered mental status 22. LABORATORY FINDINGS Early : hyperglycemia, respiratory alkalosis, hemoconcentration, WBC typically normal or low. Late : Leukocytosis, lactic acidosis VeryLate :Disseminated Intravascular Coagulation & Multi-Organ System Failure 23. Anaphylactic Shock Anaphylaxis a severe systemic hypersensitivity reaction characterized by multisystem involvement IgE mediated Anaphylactoid reaction clinically indistinguishable from anaphylaxis, do not require a sensitizing exposure Not IgE mediated 24. ANAPHYLACTIC SHOCK This type occurs due to binding of a foreign antigen to immunoglobin E (IGE) on the mast cells and basophils , releasing large amounts of histamine and SRS-A ( slow- release substance-anaphylaxis) which will produce bronchospasm , laryngeal edema and respiratory distress with hypoxia , massive vasodilatation hypotension and shock. This type occurs on exposure to penicillin , anesthetic drugs , serum injections and stings . 25. Organ systemic dysfunction ORGAN SYSTEM CNS HEART PULMONARY MANIFESTATION Encephalopathy (ischemic or septic) cortical necrosis Tachycardia/ bradycardia SVT, MI, Ventricular ectopy Acute respiratory failure, acute respiratory distress syndrome 26. Organ systemic dysfunction. . . Gastro intestinal Kidney Erosive gastritis, pancreatitis, acalculus cholecystitis, colonic submucosal hemorrhage Pre renal failure, acute tubular necrosis 27. SEVERITY OF SHOCK Compensated Mild shock Moderate Severe shock Lactic acidosis + ++ ++ +++ Urine output N N reduced anuric Level of consciousness N N drowsy comatose Respiratory rate N increased increased laboured Pulse rate Mild increase increased increased increased BP N N Mild hypotension Severe hypotension 28. Summary Type PAOP C.O. SVR HYPOVOLEMIC CARDIOGENIC DISTRIBUTIVE or N varies OBSTRUCTIVE 29. Goals of Shock Resuscitation Restore blood pressure Normalize systemic perfusion Preserve organ function 30. % Blood Volume loss < 15% 15 30% 30 40% >40% HR 100 >120 >140 SBP N N, DBP, postural drop Pulse Pressure N or Cap Refill < 3 sec > 3 sec >3 sec or absent absent Resp 14 - 20 20 - 30 30 - 40 >35 CNS anxious v. anxious confused lethargic Treatment 1 2 L crystalloid, + maintenance 2 L crystalloid, re- evaluate 2 L crystalloid, re-evaluate, replace blood loss 1:3 crystalloid, 1:1 colloid or blood products. Urine output >0.5 mL/kg/hr