Chapter 25

Furosemide

Inhibits reabsorption of sodium
and chloride from the loop of Henle
and distal convoluted tubule

Increased renal excretion of water,
sodium, chloride, potassium, and calcium

Helps to get rid of excess fluids within the bloodstream, decreasing blood pressure.

Decreased blood pressure leads to:

Decreased workload and oxygen consumption of the heart

Higher return of interstitial
fluid to capillaries in the periphery

Decreased pulmonary blood pressure,
which leads to reduced pulmonary edema, which leads to improved breathing and gas exchange.

Calcium Channel Blockers

Vasodilation of coronary artery

Increased oxygen supply to the heart

Reduces the risk of myocardial
cell death and progression of
heart failure

More oxygen to the heart
allows the heart to pump
blood more efficiently, leading
to improved circulation

Increases blood flow through
the lungs, reducing pulmonary pressure and edema. Also increases oxygenation
in the blood

Reduced pulmonary edema leads
to easier breathing

Vasodilation of peripheral arteries

Increased blood flow and
oxygenation to the periphery

Reduced peripheral edema

Decreased blood pressure

Decreased afterload

Decreased workload for the heart

Prevents worsening of heart failure

Digoxin

Increases force of myocardial
contraction (without increasing
oxygen demand)

Improves efficiency of contractions without placing extra stress on cardiac muscle

Improves overall circulation

Helps to relieve central venous pressure and reduce peripheral edema (Jung Soo's case is severe as he has gained 9 kg in the past month, likely due to his edema)

Increased blood flow through
lungs, aiding in proper oxygenation
and gas exchange.

Decreased afterload, relieving
workload of the heart.

Less oxygenation needs of the heart

Patient doesn't need to breathe
so hard anymore

Increases contractility
and cardiac output

Prolongs refractory period
of the AV node

Slows the heartbeat (negative chronotropic effect)

Allows more time for blood to enter the heart during diastole, which increases preload, allowing for a larger cardiac output

Larger cardiac output leads to
improved pumping action of the heart, reducing the need to increase the heart rate to compensate for inefficient pumping

Decreased oxygen needs

Decreased workload on the heart!