Page 240 - Critical Care Notes

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MULTISYS
■ Assess and monitor anion gap and lactate if metabolic acidosis is present.
■ Position patient to promote optimal O 2 exchange. Reposition every 2 hr.
■ Keep head of bed (HOB) elevated 45°. Use prone position if possible.
■ Institute VAP precautions if patient is on mechanical ventilation.
■ Treat fever if present.
■ Insert Foley catheter and monitor intake and output. Maintain urine output
at ≥0.5 mL/kg/hr.
■ Assess nutritional and fluid and electrolyte balance.
■ Prevent nosocomial infections.
■ Institute skin care protocols.
Shock
The four types of shock are:
■ Hypovolemic shock: Resulting from decreased circulating or intravascular
volume. Causes include hemorrhage, burns, acute pancreatitis, ascites,
dehydration.
■ Cardiogenic shock: Resulting from the inability of the heart to pump effec-
tively. Causes include MI, cardiomyopathy, left-sided heart failure, blunt
cardiac injury, acute mitral or aortic insufficiency.
■ Obstructive shock: Resulting from a physical obstruction to blood circula-
tion and inadequate blood oxygenation. Causes include pulmonary
embolism, pneumothorax, aortic stenosis.
■ Distributive shock: Resulting from maldistribution of circulating blood
volume. Examples include:
■ Septic shock (caused by an infectious process)
■ Anaphylactic shock (a hypersensitivity reaction)
■ Neurogenic shock (from alterations in vascular smooth muscle tone)
Pathophysiology
The pathophysiology of shock is complex and not fully understood. It is charac-
terized by hypoperfusion, hypercoagulability, and activation of the inflammatory
response.
■ Blood volume displaced in the vasculature → ↑ cardiac output (CO) → ↑ tis-
sue perfusion → ↑ HR and contractility with shunting of blood to the vital
organs (brain).
■ Renin-angiotensin response → angiotensin II (vasoconstriction) → release of
aldosterone and antidiuretic hormone → Na + and H 2 O retention → ↑ preload.
■ Stimulation of the anterior pituitary gland → secretion of adrenocorticotrop-
ic hormone → stimulation of adrenal cortex → release of glucocorticoids →
↑ blood glucose.
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