Ethacrynic acid in edematous states in children

Furosemide versus ethacrynic acid in pediatric patients undergoing cardiac surgery: a randomized controlled trial

Introduction

Clinical effects of furosemide (F) and ethacrynic acid (EA) continuous infusion on urine output (UO), fluid balance, and renal, cardiac, respiratory, and metabolic function were compared in infants undergoing surgery for congenital heart diseases.

Methods

A prospective randomized double-blinded study was conducted. Patients received 0.2 mg/kg/h (up to 0.8 mg/kg/h) of either F or EA.

Results

In total, 38 patients were enrolled in the F group, and 36, in the EA group. No adverse reactions were recorded. UO at postoperative day (POD) 0 was significantly higher in the EA group, 6.9 (3.3) ml/kg/h, compared with the F group, 4.6 (2.3) ml/kg/h (P = 0.002) but tended to be similar in the two groups thereafter. Mean administered F dose was 0.33 (0.19) mg/kg/h compared with 0.22 (0.13) mg/kg/h of EA (P < 0.0001). Fluid balance was significantly more negative in the EA group at postoperative day 0: −43 (54) ml/kg/h versus −17 (32) ml/kg/h in the F group (P = 0.01). Serum creatinine, cystatin C and neutrophil gelatinase-associated lipocalin levels and incidence of acute kidney injury did not show significant differences between groups. Metabolic alkalosis occurred frequently (about 70% of cases) in both groups, but mean bicarbonate level was higher in the EA group: 27.8 (1.5) M in the F group versus 29.1 (2) mM in the EA group (P = 0.006). Mean cardiac index (CI) values were 2.6 (0.1) L/min/m² in the F group compared with 2.98 (0.09) L/min/m² in the EA group (P = 0.0081). Length of mechanical ventilation was shorter in the EA group, 5.5 (8.8) days compared with the F group, 6.7 (5.9) (P = 0.06). Length of Pediatric Cardiac Intensive Care Unit (PCICU) admission was shorter in the EA group: 14 (19) days compared with 16 (15) in the F group (P = 0.046).

Conclusions

In cardiac surgery infants, EA produced more UO compared with F on POD0. Generally, a smaller EA dose is required to achieve similar UO than F. EA and F were safe in terms of renal function, but EA caused a more-intense metabolic alkalosis. EA patients achieved better CI, and shorter mechanical ventilation and PCICU admission time.

Trial registration

Clinicaltrials.gov NCT01628731. Registered 24 June 2012.

Ethacrynic Acid continuous infusions in critically ill pediatric patients

OBJECTIVES

The purpose of this study was to describe dosage regimens and treatment outcomes in critically ill children receiving ethacrynic acid continuous infusions (CI).

METHODS

This retrospective cross-sectional study evaluated patients less than 18 years of age who received ethacrynic acid CI with a duration exceeding 12 hours, from January 1, 2007, through January 31, 2012. The primary objective was to determine the mean/median doses of ethacrynic acid CI. Secondary objectives were to assess surrogate efficacy markers (e.g., urine output [UOP], fluid balance) and the number of patients with electrolyte abnormalities or metabolic alkalosis. Descriptive statistics were used. A series of repeated measures analyses of variance were conducted to assess differences in surrogate efficacy markers and in adverse events that occurred pre-, mid-, and posttherapy.

RESULTS

Nine patients were included. The mean ± SD initial and maximum doses (mg/kg/hr) were 0.13 ± 0.07 (median 0.1; range, 0.08-0.3) and 0.17 ± 0.08 (median, 0.16; range 0.09-0.3), respectively. The median UOP (mL/kg/hr) pre-, mid-, and postinfusions (interquartile range [IQR]) were 2.4 (1.8-3.2), 4.2 (3.5-6), and 4 (3.4-5.3), respectively. The median fluid balance (mL; IQR) was 189 (90-526), -258 (-411.7 to 249) and -113.5 (-212.5 to 80.2), respectively. There were statistically significant differences in UOP and fluid balance pre- versus mid-therapy (0.014) and pre- versus posttherapy (p=0.010). No significant differences were noted with magnesium and potassium. Five children (55.6%) developed metabolic alkalosis.

CONCLUSIONS

This study provides preliminary evidence for ethacrynic acid CI in children. The median initial dose and maximum dose in this cohort were 0.13 mg/kg/hr and 0.17 mg/kg/hr, respectively. Larger prospective studies are needed to confirm these findings.

The pharmacology and therapeutics of diuretics in the pediatric patient

Selection of appropriate diuretic therapy in children is hampered by a lack of age-specific pharmacokinetic and pharmacodynamic data, especially in premature neonates. Well-designed clinical trials in neonates, infants, and younger children are necessary prerequisites to safer and more efficacious diuretic therapy.

Pharmacology of diuretics in the newborn

Diuretics are used in various conditions with fluid overload. Their efficacy in the management of congestive heart failure is well documented. In contrast, the indication of diuretics in chronic lung disease and central nervous system disorders of the newborn have not been clearly established. Substantial pharmacologic knowledge of diuretics in the young infant remains to be described. Most investigations on diuretics in the sick newborn infant have examined furosemide. In contrast, the pharmaco-dynamics, pharmacokinetics, clinical indications, and toxicity of other diuretics used in the newborn require considerable further evaluation. Future studies using a combination of diuretics, acting at different segments of the nephron, also may provide newer therapeutic modalities to overcome or prevent the development of frequently observed tolerance to diuretics, as well as to treat refractory edema.

Diuretic therapeutics in the pediatric patient

Careful management of fluid and electrolytes has long been an intrinsic part of pediatric practice. However, the augmentation of these manipulations through the rational use of diuretic agents requires considerable skill. In pediatric medicine, the regulation of pharmacokinetic processes and their interface with pharmacodynamic processes show dramatic age-related changes. These ontogenetic processes and their modification by various disease states must be considered carefully before selection and application of diuretic agents. The available data concerning the ontogeny of renal function and the attempts to apply diuretic therapy to pediatric disease are reviewed. It is concluded that results obtained to date suffer from the absence of a rigorous attempt to answer the fundamental therapeutic questions: What drug? What dose? What duration of therapy? A rational "target-effect" strategy is proposed for the application of diuretic agents to pediatric medicine.

Effects of ethacrynic acid in the newborn infant

The effects of ethacrynic acid on electrolyte and water excretion were examined in 10 neonates with fluid overload states. Ethacrynic acid (1 mg/kg IV) produced a 10-fold increase in FENa+ and FECl - and a sixfold increase in urine volume and osmolar clearance. These effects peaked within 1 hour of ethacrynic acid administration, and progressively decreased to the baseline value by 5 hours after drug administration. The mean excretion of potassium increased by 280% in 1 hour, and returned to baseline value after 5 hours. The mean Ca++ excretion increased fourfold after 1 hour, and the effect lasted for 4 hours. Two infants developed mild hyponatremia. Our data emphasize the prolonged diuretic and saluretic effect of ethacrynic acid in neonates.