Shock and Infarction Flashcards
Clinical consequences of shock
Hypotension Tachycardia Tachypnea Cyanosis Acidosis Electrolyte imbalance Renal insufficiency
Major factors contributing to pathophysiology of sepsis
Inflammatory mediators Endothelial cell injury Metabolic abnormalities Immunosuppression Organ dysfunction
Pathogenesis of septic shock
Bacteria
Inflammation-> vasodilation and vascular leakage-> decrease in TPR
Inflammatory mediatory-> heart contractility and endothelial dysfunction -> DIC
DIC-> hypoperfusion -> multiple organ failure
Neurogenic shock
Loss in vascular tone due to anesthetics or 2° to spinal cord injury
Anaphylactic shock
Vasodilation and vascular leakage due to igE mediated hypersensitivity reaction in allergy
Non progressive stage
Baroreceptor reflex ADH release Catecholamine/ sympathetic stimulation Renal-angiotensin-alderosene axis Tachycardia, peripheral vasoconstriction, Tachypnea, renal fluid conservation
Progressive stage
Hypoxia->Acidosis->Vasodilation
DIC
ARDS & ATN
Irreversible stage
Widespread tissue injury
Bacteremic shock
Organ failure-> death
Red infarction
Dual supply
Loose tissue- lung, small intestine, liver, hand
Sluggish supply do to previous congestion
Repercussion
Venous occlusion of single efferent vein organs
White Infarct
Arterial occlusion of dense organs and continuous drainage by lymph
Heart, spleen, kidney, retina
Factors of infarction
Nature of vascular supply
Rate of occlusion formation
Vulnerability to hypoxia
Oxygen content of the blood
Effects/ outcome of infarct
Sudden death
Scar formation
Organ dysfunction
2° infections
Systemic effect- fever, neutrophil leukocytosis
Local effect- swelling, rupture, hemorrhage, pressure effects
Hypovolemic shock
Due to hemorrhage, burns, vomit, diarrhea
Cardiogenic shock
Pump failure or obstruction of outflow Myocardial infarction Arrhythmias Valvular disease Myocarditis Pulmonary embolism Cardiac tamponade
