# Prophylactic Intravenous Furosemide for Reducing Hyponatremia Risk in Monopolar Transurethral Prostate Surgery: A Randomized Clinical Trial

## TL;DR

A study found that giving furosemide before prostate surgery can lower the risk of low sodium levels, a common complication, but may also increase the risk of low potassium in some patients.

## Contribution

This is the first randomized clinical trial to evaluate prophylactic furosemide's effectiveness in preventing hyponatremia during monopolar TURP.

## Key findings

- Furosemide significantly reduced hyponatremia incidence compared to the control group.
- Furosemide increased postoperative serum sodium levels but decreased potassium levels.
- Mild hypokalemia occurred in patients with baseline potassium below 4.1 mmol/L.

## Abstract

Transurethral resection of the prostate (TURP) is the gold standard surgical treatment for benign prostatic hyperplasia (BPH). Despite its widespread use, monopolar TURP carries a risk of significant complications, particularly transurethral resection (TUR) syndrome leading to hyponatremia and fluid overload. The study evaluates whether prophylactic furosemide prevents hyponatremia and TUR syndrome in monopolar TURP.

This study was a triple-blind randomized clinical trial conducted in Al-Zahra and Khorshid educational hospitals of Isfahan, Iran, in 2022-2023. Patients undergoing monopolar TURP,
were divided into two groups: those receiving preoperative furosemide and a control group. The primary outcomes were changes in serum sodium levels and the incidence of hyponatremia.
Secondary outcomes included fluid balance, complication rates, and recovery times. Continuous data were analyzed using t test/Mann-Whitney U, categorical data with Fisher’s exact test, and time-based changes with repeated measures ANOVA. Normality was checked via Kolmogorov-Smirnov, and power analysis determined sample size.

The furosemide group demonstrated a significantly lower incidence of hyponatremia than the control group (P=0.008).
Additionally, serum sodium levels were significantly higher in the furosemide group after surgery (P=0.011), while potassium levels were lower (P=0.003).
Mild hypokalemia was observed as a manageable side effect, primarily in patients with baseline potassium levels below 4.1 mmol/L.

Preoperative administration of furosemide effectively reduces the risk of TUR syndrome during monopolar TURP. Furosemide effectively reduces hyponatremia but may increase hypokalemia in some cases, limiting its clinical utility during monopolar TURP. Patient-specific assessment and further research are needed to ensure its safe and effective use.

Trial Registration Number: IRCT20211208053328N2.