Jumat, 28 Oktober 2011

SHOCK BY DODDY YP SKep.Ns • Define the major types of shock and principles of management • Review fluid resuscitation, vasopressors and inotropes • Address the balance of O2 supply and demand • Discuss the differential diagnosis of oliguria • Always a symptom of its cause • Abnormally low organ perfusion usually associated with decreased blood pressure • Signs of organ hypoperfusion: mental status change, oliguria, acidosis • Cardiogenic • Hypovolemic • Distributive • Obstructive Syok kardiogenic • Decreased contractility • Increased filling pressures, decreased LV stroke work, decreased cardiac output • Increased systemic vascular resistance – compensatory Shock hypovolemic • Decreased cardiac output • Decreased filling pressures • Compensatory increase in systemic vascular resistance Distribution shock • Normal or increased cardiac output • Low systemic vascular resistance • Low to normal filling pressures • Sepsis, anaphylaxis, neurogenic, and acute adrenal insufficiency Obstruktive shock • Decreased cardiac output • Increased systemic vascular resistance • Variable filling pressures – etiology dependent • Cardiac tamponade, tension pneumothorax, massive pulmonary embolus Management shock kardiogenic • Treat arrhythmias • Diastolic dysfunction may require increased filling pressures • Vasodilators if not hypotensive • Inotrope administration • Vasopressors if hypotensive to raise aortic diastolic pressure • Mechanical assistance • Consultation Management shock hypovolemic • Volume resuscitation – crystalloid, colloid • Initial crystalloid choices – Lactated Ringer’s solution – Normal saline (high chloride may produce hyperchloremic acidosis) • Match fluid given to fluid lost – Blood, crystalloid, colloid Distribusi terapi shock • Expand intravascular volume • Hypotension despite volume therapy – Inotropes • Vasopressors for MAP < 60 mm Hg • Adjunctive antibiotics in sepsis Threatmen shock obstruktive • Relieve obstruction – Pericardiocentesis – Tube thoracostomy – Treat pulmonary embolus • Temporary benefit from fluid or inotrope administration Managemen shock • Increase O2 delivery • Optimize O2 content of blood • Improve cardiac output and blood pressure • Match systemic O2 needs with O2 delivery • Reverse/prevent organ hypoperfusion Managemen fluid • Crystalloids – Lactated Ringer’s solution – Normal saline • Colloids – Hetastarch – Albumin • Packed red blood cells • Infuse to physiologic endpoints • Correct hypotension first • Decrease heart rate • Correct hypoperfusion abnormalities • Monitor for deterioration of oxygenation Agen vasopresur • Dopamine – Low dose (2-3 mg/kg/min) – mild inotrope plus renal effect – Intermediate dose (4-10 mg/kg/min) – inotropic effect – High dose ( >10 mg/kg/min) – vasoconstriction – Chronotropic effect • Dobutamine – 5-20 mg/kg/min – Inotropic and variable chronotropic effect – Decrease in systemic vascular resistance • Norepinephrine – 0.05 mg/kg/min and titrate – Inotropic and vasopressor effects – Potent vasopressor at high doses Epineprin • Both a and b actions for inotropic and vasopressor effects • 0.1 mg/kg/min and titrate • Increases myocardial O2 consumption Oligury • Marker of hypoperfusion • Urine output in adults <0.5 mL/kg/hr for 2 hrs • Etiologies – Prerenal – Renal – Postrenal Evaluation oligury • History and physical examination • Laboratory evaluation – Urine sodium – Urine osmolality or specific gravity – BUN, creatinine Definitions The term shock is used to describe a variety of disorders in which there is a failure of oxygen supply to the tissues. Oxygen supply to the tissues may be impaired because of : 1. respiratory failure 2. cardiac failure 3. inadequate circulating blood volume