SHOCK Alnasser Abdulaziz Alomari Mohammed Alhomoud Homoud

Objective Definition. Pathophysiology. Sign and symptoms. Types of shock. Management. Summery.

WHAT IS SHOCK? Shock is the term used to describe acute circulatory failure with inadequate or inappropriately distributed tissue perfusion resulting in generalized cellular hypoxia and/or an inability of the cells to utilize oxygen. 3

PATHOPHYSIOLOGY OF SHOCK The manifestation of shock reflects both – The impaired perfusion of body tissue & – The body’s attempt to maintain tissue perfusion (compensatory mechanism) 4

Inadequate tissue perfusion Decreased oxygen supply Anaerobic metabolism Accumulation metabolic waste & lactate Cellular failure (limited ATP produce) Pathophysiology of shock cellular responses 5

VICIOUS CYCLE HypoperfusionCellular injury Inflammatory mediators Functional & structural changes in microvascular circulation 6

Global Tissue Hypoxia Endothelial inflammation and disruption Inability of O2 delivery to meet demand Result: Lactic acidosis Cardiovascular insufficiency Increased metabolic demands 7

Symptoms of Shock Anxiety /Nervousness Dizziness Weakness Faintness Nausea & Vomiting Thirst Confusion Decreased UO Hx of Trauma / other illness Vomiting & Diarrhoea Chest Pain Fevers / Rigors SOB General SymptomsSpecific Symptoms 8

Signs of Shock Pale Cold & Clammy skin Sweating Cyanosis Tachycardia Tachypnoea Confused / Aggiatated Unconscious Hypotensive Stridor / SOB 9

TYPES OF SHOCK HYPOVOLEMIC CARDIOGENIC DISTRIBUTIVE 10

Hypovolaemic Volume Loss Blood loss -Haemorrhage Plasma Loss-Burns ECF Loss- Vomiting & Diarrhoea 11

Compensatory mechanism and shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 12

Hypovolaemic shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 1 13

Hypovolaemic shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 1 14

Hypovolaemic shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD

Hypovolaemic shock Management Hemorrhage: Arrest of bleeding & fluid resuscitation. Two wide bore (14-16 gauge) peripheral venous access. Crystalloid infusion- titrated to clinical response. PRBCs: Life threatening/ continued bleeding. Diagnosis & treatment: Source of bleeding/ other causes Invasive monitoring. Urine output monitoring- Foley catheter

Cardiogenic Pump Failure May be due to – Inability of heart to Contract or – Inability of heart to pump blood Myocardial damage ( M.I) Arrhythmias Valvular damage 17

Compensatory mechanism and shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 18

Cardiogenic shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 1 19

Cardiogenic shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD

Cardiogenic shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD

Cardiogenic Shock management Maintenance of adequate oxygenation. Carful fluid administration to avoid fluid overload. Cardiology consultation. Thoracocenteasis, pericardiocentesis in trauma.

Distributive Decreased Peripheral Vascular Resistance Septic Shock (inflammatory mediators) Neurogenic Shock (loss of sympathetic control on vascular tone) Anaphylactic shock (presence of vasodilator substances like histamine) 23

Compensatory mechanism and shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 24

Distributive shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 1 25

Distributive shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD 21 26

Distributive shock Fluid Volume (CVP/JVP) Vascular Diameter (SVR) Cardiac Output (SV x HR) PRE-LOAD AFTER-LOAD

septic shock management Crystalloid infusion ( target CVP ≥8 mmHg). Urine output: ≥0.5 ml/kg/hr. Vasopressors(noradrenaline):Persistent hypotension, after volume restoration- Serum lactate: Monitor tissue perfusion. Identification of underlying infection: History, examination & investigations (blood culture, radiological). Treatment of infection: IV antibiotics(empirical, post-culture)

Neurogenic shock management Airway secured, adequate ventilation. Fluid resuscitation to restore intravascular volume. Administration of vasopressor.

Anaphylactic shock management Stop administration of causative agent. Maintain airway, give 100% O₂. Adrenaline mg IM. IV crystalloid. 2 nd line: Antihistamine- chlorphenamine 1—20 mg slow IV or Hydrocortisone 200 mg IV

Shock Types & Physiology ShockCVPCOPVR Hypovolemic↓↓↑ Septic↓↑↓ Cardiogenic↑↓↑ Neurogenic↓↓↓ Anaphylactic↓↑↓

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