A nurse is evaluating the effectiveness of IV furosemide in a child with congestive heart failure (CHF). Which finding indicates improvement?

Choice A rationale Weight gain of 1 kg suggests fluid retention, which is contrary to the expected diuretic effect of furosemide. Furosemide, a loop diuretic, acts by inhibiting the Na+-K+-2Cl- cotransporter in the thick ascending limb of the loop of Henle, increasing water and electrolyte excretion. A decrease in body weight due to diuresis is the primary indicator of effectiveness in reducing fluid overload associated with CHF. Choice B rationale Decreased urine output indicates a diminished response to the diuretic, suggesting ineffectiveness or potential complications like dehydration or pre-renal injury. Effective diuresis should significantly increase the urine output, facilitating the removal of excess interstitial and intravascular fluid volume to alleviate the symptoms of pulmonary and systemic congestion in CHF. Normal urine output for children is typically 1 to 2 mL/kg/hr. Choice C rationale Increased crackles, also known as rales, are adventitious lung sounds that signify the presence of fluid in the alveoli and small airways, characteristic of pulmonary edema in CHF. Furosemide aims to decrease this fluid, improving oxygenation and reducing the audible crackles, making an increase an indicator of worsening condition or ineffective treatment. Choice D rationale Decreased respiratory rate often accompanies improved oxygenation and reduced work of breathing, secondary to the resolution of pulmonary congestion and edema. Furosemide's action reduces the fluid burden on the lungs, lowering the hydrostatic pressure and facilitating gas exchange, which in turn reduces the tachypnea and respiratory distress common in pediatric CHF.