Electrolyte imbalance and its determinants between low and high dose of furosemide in patients admitted to tertiary care hospital of Nepal: A prospective cohort study

Background Electrolytes imbalances are common complications observed in patients admitted to hospital. Furosemide, a loop diuretic, is frequently prescribed to enhance diuresis and manage fluid overload. However, the use of furosemide has been associated with the potential for electrolyte disturbances, particularly at higher doses. Methods The study employed an observational prospective cohort design with age and gender as cohort defining characteristics. The patients were followed over a defined period and divided into two groups based on their furosemide dosage: a low-dose group (less than 40 mg/day) and a high-dose group (40 mg/day or more). Longitudinal data on electrolyte levels were collected at regular intervals to compare electrolyte disturbance over the time between two groups. Results At baseline, sodium and potassium levels were similar between the low-dose and high-dose groups. Over time, both groups experienced decreases in sodium and potassium levels. Sodium levels showed significant variations over time (p < .001) and an interaction effect with the dose of furosemide (p < .001), with significant linear trends (p < .001) but non-significant quadratic (p = 0.873) and cubic trends (p = 0.169). Potassium levels also showed significant linear (p < .001) and quadratic trends (p = 0.023) over time, with a significant interaction effect of furosemide dosage (p < .001). Conclusion Furosemide dosage significantly affects sodium and potassium levels over time, with notable linear trends in both electrolytes and additional quadratic trends in potassium levels. This highlights the importance of monitoring electrolyte balance in patients on furosemide therapy.