PHARM: CRITICAL CARE

vasoactive infusions

inotropes: act by increasing the force of myocardial contractility

vasopressors: mimic sympathetic nervous system to cause vasoconstriction

INDICATED: cardiac arrest, hypotension, shock refractory to fluid resuscitation, cardiac disease

• SE: arrhythmias, hypoperfusion to extremities, kidneys, and GI, peripheral tissue necrosis, myocardial ischemia

epinephrine

INDICATED: shock, cardiac arrest, asystole

• LOW doses act on beta 1: increasing CO

• HIGH doses act on alpha 1: increase systemic vascular resistance, increase BP

norepinephrine

INDICATED: shock, hypotension

• acts on alpha 1 receptors

• causes peripheral vasoconstriction, increasing BP and CO

phenylephrine

INDICATED: anesthesia induced hypotension, second line in some shock

• ONLY act on alpha 1

• causes ONLY vasoconstriction, no inotropy, increasing BP

dopamine

INDICATED: shock, hypotension, trauma

• LOW doses used in kidney failure to increase renal blood flow

• LOW doses increase contractility; increase CO

• HIGH doses cause vasoconstriction; increase systemic vascular resistance; increase BP

• acts on dopamine receptors

vasopressin (ADH)

• antidiuresis=more volume in the vascular system

  • more volume=more pressure, raising BP

• second line in vasodilatory shock

• third line in septic shock

  • 1st: dopa or norepi

  • 2nd: epi or phenylphrine

  • 3rd: vaso

milrinone

INDICATED: cardiogenic shock, decreased CO, congenital/acquired heart defects

• causes systemic and pulmonary vasodilation—decreasing afterload and increasing contractility doing so by inhibiting the breakdown of cAMP (cyclic adenosine monophosphate) by phosphodiesterase