Classification of shock

classification of shock

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 : ⑴ Hypodynamic Shock: Cardiac Output , Vascular Resistace , Cold Skin; ⑵ 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 >38.5ºC or <35ºC • Heart rate >90 beats/min • Respiratory rate >20 breaths/min or PaCO2, <32 torr (<4.3 kPa ) • White blood count >12,000 cells/mm3, <4000 cells/mm3, or >10% immature (band) cells

19. Multiple Organ Dysfunction Syndrome (MODS) • Progressive distant organ failure (initially uninvolved) following severe infectious or noninfectious insults (severe burn, multiple trauma, shock, acute pancreatitis)

20. STAGES OF SEPTIC SHOCK WARM SHOCK Inflammatory triad fever tachycardia flushed skin Hyperperfusion altered sensorium urine output >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 >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