Diuretic Therapy in Acute Cardiac Failure
(Short Note)
Features of Acute Cardiac Failure
Tachycardia
Dyspnoea
Basal crepitations and rales
Hepatomegaly
Raised Jugular Venous Pulse
Due to inefficient pumping by the heart, fluid retention occurs leading to pulmonary oedema
Due to lack of adequate circulation kidney function is impaired and salt (Sodium) retention occurs which in turn causes retention of water thereby increases the volume of blood / volume load on the heart.
Introduction
A diuretic is one of the first medications prescribed to a patient with CHF.
Diuretics promote the excretion of sodium and water through kidneys.
These medications may not be necessary if the patient responds to activity recommendations, avoidance of excessive fluid intake, and a low sodium diet. (e.g. 2 g / day)
Mechanism of action: by excreting sodium and water diuretics reduce volume load to the heart;
Clear the fluid from the alveoli thereby reducing the pulmonary edema and increasing oxygen pefusion into the blood
Effects of Diuretic Therapy
Increases urinary output
Reduces the volume of blood
Decreases volume load to the heart
Decreases the pulmonary oedema by removing fluid collection from the alveoli
Diuretic Medications Used to Treat Cardiac Failure: -
Thiazide Diuretics
Bendroflumethiazide
Benzthiazide
Chlorothiazide
Hydrochlorothiazide
Hydroflumethiazide
Loop Diuretics
Ethacrinic acid
Furosemide (Lasix)
Torsemide (Torsinex)
Inj.Laxis (Furosemide/Frusemide) - Loop Diuretic - Acts mainly on Loop of Henle - increases the excretion of water and Sodium
Potassium-sparing Diuretics
Amiloride
Spironolactone (Aldactone)
Triamterene
Furosemide also causes vasodilation and pooling of blood in peripheral bloodvessels, which reduces the amount of blood returned to the heart, even before the diuretic effect.
Initially Inj.Lasix 20 - 100 mg may be administered as iv bolus dose.
It may be repeated every 6 - 12 hours for the first 2-3 days
Once the patient is stabilized Tab.Lasix may be given once or twice daily.
Can switch over to potassium conserving diuretics like Lasilactone (furosemide + spironolactone) to prevent hypokalemia
If furosemide is continued a potassium supplement has to be administered daily (Potklor - one tsf in one cup of water once daily)
Nursing intervention
Administering and monitoring diuretic therapy
The patient receiving diuretic therapy may excrete a large volume of urine within minutes after a potent diuretic is administered.
A bedside commode may be used to decrease the energy required by the patient and to reduce the resultant increase in cardiac
workload induced by getting on and off a bedpan. If necessary, an indwelling urinary catheter may be inserted
Other measures : positioning of the patient, Morphine, Deriphylline, nurse remaining with the patient to reassure, alleviate anxiety by dealing with the worries of the patient about children, family, money, jewels, presence of the relatives nearby etc.
