Loop diuretics continuous infusion

Increase loop diuretic dose Loop diuretic continuous infusion Add second diuretic Ultrafiltration... 

Several adaptive mechanisms by the kidney limit effectiveness of loop diuretic therapy. Postdiuretic sodium retention occurs as the concentration of diuretic in the loop of Henle decreases. This effect can be minimized by decreasing the dosage interval (i.e., dosing more frequently) or by administering a continuous infusion. Continuous infusion loop diuretics may be easier to titrate than bolus dosing, requires less nursing administration time, and may lead to fewer adverse reactions. 

Equipotent doses of loop diuretics (furosemide, bumetanide, torsemide, ethacrynic acid) have similar efficacy. Ethacrynic acid is reserved for sulfa-allergic patients. Continuous infusions of loop diuretics appear to be more effective and to have fewer adverse effects than intermittent boluses. An initial IV loading dose (equivalent to furosemide 40 to 80 mg) should be administered before starting a continuous infusion (equivalent to furosemide 10 to 20 mg/hour). 

Loop diuretics, particularly when administered by continuous infusion, increase urine volume and renal sodium excretion. Although thiazide... 

Furosemide is a widely used loop diuretic indicated for the treatment of different pathological conditions such as congestive heart failure, hepatic cirrhosis, and chronic renal failure. It has a narrow absorption window and mainly absorbed from the stomach and the upper part of the small intestine. Following administration of furosemide, the natriuretic effect rapidly disperses and is concealed before the next administration. This problematic aspect in furosemide therapy is mostly attributed to the natural homeostatic compensatory mechanisms. Lately, it has been demonstrated that the diuretic and natriuretic effects of furosemide can be significantly improved, following a continuous input (intravenous infusion) compared to immediate release DFs. Beside the narrow absorption window, this pharmacodynamic feature of the drug provides another rationale for the development of a GRDF for furosemide. 

An alternative in the diuretic-resistant patient is the use of continuous infusions of loop diuretics rather than bolus diuretic therapy. Such infusions can also be given with a small volume of hypertonic saline, with good effect (39). The reasons why continuous infusions of loop diuretics work when bolus doses have failed may relate to a more efficient time-course of diuretic delivery and/or less activation of the renin-angiotensin system (40). Furosemide and torasemide may be the safest loop diuretics to be given as infusions, in that infusion of bumetanide has been associated with severe musculoskeletal symptoms (41). 

Ravnan SL, Ravnan MC. Management of adult heart failure bolus versus continuous infusion loop diuretics, a review of the literature. Hosp Pharm 2000 35 832-6. 

In the treatment of acute myocardial failure with associated pulmonary oedema, the objectives are to improve gas exchange, increase myocardial contractility and reduce the workload of the left ventricle. Dobutamine, a somewhat selective pi -adrenoceptor agonist, produces a pronounced inotropic effect that results in an increased cardiac output (where contractility is the limiting factor) and an elevation of arterial blood pressure. The drug preparation, following appropriate dilution, is administered by continuous intravenous infusion at a rate of 1-5 (ig/kg min. An intravenous dose (0.5 mg/kg) of furosemide (loop diuretic) increases venous capacitance by redistributing venous blood from the lungs to the peripheral circulation, which... 

Diuretic therapy is often necessary to prevent edema from volume overload and prevent the associated symptoms. Loop diuretics, particularly when administered by continuous infusion, increase urine volume and renal sodium excretion. A combination of a loop diuretic along with a thiazide diuretic (such as hydrochlorothiazide or metolazone) can result in a profound excretion of sodium and water. Alone, thiazide diuretics are ineffective in patients with a GFR below 30 mL/min (see Chap. 49). 

Rudy DW, Voelker JR, Greene PK, et al. Loop diuretics for chronic renal insufficiency A continuous infusion is more efficacious than bolus therapy. Ann Intern Med 1991 115 360-366. 

While maintaining other diuretics, switch loop agent to continuous infusion... 

In an editorial review, it was stated that addition of furosemide to desmopressin in elderly patients to reduce nocturia led to incidence of hyponatraemia in 4% out of 82 study patients [16]. Similarly, in a retrospective study, use of low-dose continuous furosemide infusion in 150 patients with acute HF developed hyponatraemia in 38%, hypokalemia in 25% and hypomagensemia in 15% of patients [12]. The EIDOS and DoTS descriptions of electrolyte disturbances due to loop diuretics, thiazide and thiazide-like diuretics have been described in previously [SEDA-35, 389]. 

---