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172 Cardio Diabetes Medicine 2017

ceptions include patients with severe hypotension or necessary. A continuous intravenous infusion is an
cardiogenic shock.Patients with aortic stenosis with alternative to intravenous bolus therapy, although
volume overload should be diuresed with caution. data are limited in its favour. Use of a continuous
intravenous infusion requires that the patient be re-
Even in the less common situation in which cardio- sponsive to intravenous bolus therapy. Adding a thia-
genic pulmonary edema develops without significant zide diuretic may potentiate the effect, but hypokale-
volume overload (eg, with hypertensive emergency, mia may occur.The onset of diuresis typically occurs
acute aortic or mitral valvular insufficiency), fluid re- within 30 minutes with peak diuresis usually at one
moval with intravenous diuretics can relieve symp- to two hours after intravenous diuretic administra-
toms and improve oxygenation. Intravenous rather tion. Switching from an effective intravenous dose
than oral administration is recommended because to an oral regimen is done once the patient’s acute
of greater and more consistent drug bioavailability..
symptoms have been stabilized with careful attention
to HF status, supine and upright hypotension, renal
Diuretic administration function, and electrolytes.
Individualized dosing — Diuretic dosing should be in-
dividualized and titrated according to patient status Monitoring — Volume status to prevent hypovolemia,
and response. The approach to initial diuretic therapy evidence of congestion, oxygenation, daily weight,
in patients with ADHF and fluid overload varies ac- fluid intake, and output as well as dyselectrolyte-
cording to whether or not the patient has received mia esp potassium , magnesium and sodium levels,
prior loop diuretic therapy: worsening renal parameters and hypotension should
be continually reassessed. Reductions in right and
For patients who have not previously received loop left heart filling pressures with diuresis are frequently
diuretic therapy, the following are common initial associated with augmented forward stroke volume
intravenous doses of loop diuretics in patients with and cardiac output, due to reduction in right ventric-
normal renal function: ular volume with relief of interdependent LV com-
•Furosemide – 20 to 40 mg intravenously pression and improved LV distensibility .However.
patients with HF with preserved LVEF or restrictive
•Bumetanide – 1 mg intravenously physiology and those on angiotensin converting en-

•Torsemide – 10 to 20 mg intravenously zyme (ACE) inhibitor or angiotensin receptor blocker
(ARB) therapy may be more sensitive to diuresis-in-
If there is little or no response to the initial dose, duced hypotension.
the dose should be doubled at two-hour intervals as
needed up to the maximum recommended doses. Renal function
While patients with a relatively normal glomerular fil-
tration rate can usually be diuresed with intravenous Patterns of change — The blood urea nitrogen (BUN)
doses of 40 to 80 mg of furosemide, 20 to 40 mg of and serum creatinine often rise during diuretic treat-
torsemide, or 1 to 2 mg of bumetanide, patients with ment of ADHF and in the absence of other causes
renal insufficiency or severe HF may require higher for an elevated BUN, a disproportionate rise in BUN
maximum bolus doses of up to 160 to 200 mg of relative to serum creatinine (BUN/serum creatinine
furosemide, 100 to 200 mg of torsemide, or 4 to 8 ratio >20:1) suggests a prerenal state with increased
mg of bumetanide . passive reabsorption of urea. An initial rise in BUN
may be accompanied by a stable serum creatinine,
Patients treated with loop diuretics chronically may reflecting preserved GFR. An otherwise unexplained
need a higher dose in the acute setting with initial rise thereon in serum creatinine alone reflects a re-
intravenous dose equal to or greater than (eg, 2.5 duction in GFR and is a marker of reduced perfusion
times) their maintenance total daily oral dose and to the kidney and other organs. Among patients with
then adjusted depending upon the response (eg, an an elevated central venous pressure, the associat-
initial intravenous furosemide dose of 40 to 100 mg ed increase in renal venous pressure can reduce the
for a patient who had been taking 40 mg orally per GFR, while lowering venous pressure with diuretics
day). In the DOSE trial of intravenous furosemide and other therapies might therefore increase the
in patients with ADHF, there was an almost signif- GFR. Nevertheless, fluid removal may still be required
icant trend toward greater improvement in patients’ to treat signs and symptoms of congestion, partic-
global assessment of symptoms in the high-dose ularly pulmonary edema. On the other hand, a sta-
(2.5 times the patients’ prior total daily diuretic dose) ble serum creatinine suggests that perfusion to the
group compared to the low-dose group.Bolus diuretic kidneys (and therefore to other organs) is being well
administration two or more times per day may be

GCDC 2017