Benign Prostatic Hyperplasia (BPH) is one of the most common urological disorders affecting men over 50 years of age. Histological evidence of prostatic enlargement is seen in more than 50% of men above 60 years and up to 88% by the age of 80. It is an age-dependent disease characterized by non-malignant proliferation of stromal and epithelial components of the prostate gland, primarily in the transition zone surrounding the urethra. The resulting compression leads to bladder outlet obstruction, lower urinary tract symptoms (LUTS), and secondary complications such as urinary retention, infection, and renal insufficiency.[1] Clinically, patients present with irritative symptoms-nocturia, urgency, and frequency-and obstructive symptoms such as weak stream, intermittency, hesitancy, and post-void dribbling. The International Prostate Symptom Score (IPSS) is a validated tool used to grade symptom severity and monitor treatment outcomes. While medical therapy using alpha-adrenergic blockers and 5-alpha-reductase inhibitors can provide symptomatic relief, surgical intervention remains the gold standard for patients with moderate to severe symptoms or failure of medical therapy.[2] Transurethral Resection of the Prostate (TURP) continues to be the benchmark surgical procedure for BPH management. It involves resection of hypertrophic prostate tissue through an endoscopic route using an electrocautery loop under continuous irrigation. Despite its proven efficacy, conventional monopolar TURP carries several well-known complications, most notably TUR syndrome, a potentially fatal condition resulting from systemic absorption of hypotonic irrigation fluids such as glycine or distilled water. The absorbed fluid may cause acute water intoxication, dilutional hyponatremia, cerebral edema, and cardiovascular collapse. The incidence of mild to severe hyponatremia has been reported in up to 25% of monopolar TURP cases.[3] The pathophysiology of TUR syndrome depends on the rate and volume of absorbed irrigation fluid. When hydrostatic pressure of the irrigation fluid exceeds the venous pressure of prostatic sinusoids (typically 10-15 mm Hg), absorption occurs at approximately 20 mL/min, potentially reaching 1000-1200 mL in the first hour of resection. Larger gland size (>45 g), longer operative time (>90 min), and high irrigation pressure markedly increase the risk of hyponatremia and fluid overload. Reported symptoms include headache, restlessness, confusion, nausea, visual disturbances, and seizures. In severe cases, bradycardia, hypotension, pulmonary edema, and death may ensue.[4] The development of bipolar electrosurgical systems has significantly improved the safety profile of TURP. Bipolar resectoscopes operate within a closed electrical circuit, allowing the use of isotonic saline (0.9% NaCl) as the irrigant instead of non-conductive glycine. This eliminates the risk of dilutional hyponatremia and TUR syndrome while providing efficient cutting and coagulation. Additionally, bipolar energy minimizes collateral thermal injury, reduces bleeding, and permits faster postoperative recovery. Studies have also shown bipolar systems to be advantageous in patients with large prostates, cardiac pacemakers, and those at higher anesthetic risk.[5] Aim To compare the safety and efficacy of bipolar versus monopolar cautery techniques in transurethral resection of the prostate (TURP). Objectives 1. .To analyze serum electrolyte changes and their clinical relevance in patients undergoing bipolar and monopolar TURP. 2. 2. To assess intraoperative and postoperative hemodynamic stability, fluid absorption, and complications in both groups. 3. To evaluate the overall safety and efficacy outcomes between bipolar and monopolar cautery systems.

Source of Data The study was conducted on patients diagnosed with benign prostatic hyperplasia (BPH) undergoing transurethral resection of the prostate (TURP) in the Department of Urology, Super Specialty Hospital, Nagpur. Data were collected from operative and laboratory records with informed written consent from each participant. Study Design A prospective comparative study. Study Location Department of Urology, Super Specialty Hospital, Nagpur. Study Duration June 2021 - January 2023 (approximately 1.5-2 years). Sample Size Calculated using n-Master 2.0 software based on mean sodium decline difference between groups (Monopolar 4.12 ± 5.8 mEq/L; Bipolar 1.3 ± 5.45 mEq/L), with α = 0.05 and power = 80%. • Group GM (Monopolar with Glycine 1.5%) = 35 patients • Group NSB (Bipolar with Normal Saline) = 35 patients Inclusion Criteria • Patients aged 40-80 years with clinically and ultrasonographically confirmed BPH. • ASA grade I or II patients scheduled for elective TURP. • Patients with or without controlled comorbidities who were hemodynamically stable. • Written informed consent obtained. Exclusion Criteria • Patients refusing consent. • Age < 40 or > 80 years. • ASA grade III-V. • Patients undergoing open prostatectomy or Frayer’s procedure. • Hemodynamic instability, bleeding disorders, uncontrolled hypertension or diabetes, old MI, or CVA history. • Intraoperative blood transfusion requirement. Procedure and Methodology All patients underwent spinal anesthesia using 3 mL of 0.5% bupivacaine (heavy) via 23G spinal needle at L3-L4/L4-L5 space. Standard intraoperative monitoring (ECG, HR, BP, SpO₂) was maintained. • Group GM (Monopolar): Resection was performed using 1.5% glycine as irrigant with monopolar cautery. • Group NSB (Bipolar): Resection used 0.9% normal saline as irrigant with bipolar cautery. The irrigation fluid reservoir was maintained at 60 cm above the operative table in both groups. The procedures were performed by surgeons of equal expertise. Continuous monitoring of vitals was carried out every 10 minutes. Hypotension (SBP < 70 mmHg) was treated with IV mephentermine 6 mg; bradycardia (HR < 60/min) was treated with IV atropine 0.3-0.6 mg. Any patient requiring transfusion was excluded. At the completion of resection, operative time, volume of irrigant used, intraoperative hemodynamics, and perioperative symptoms were documented. Blood samples were collected immediately before and after the procedure to measure serum sodium and potassium. Sample Processing Five mL of venous blood was drawn pre- and post-operatively. Serum was separated by centrifugation at 3000 rpm for 10 minutes. Sodium and potassium were estimated using Flame Emission Spectrophotometry, calibrated with lithium/cesium internal standards for precision. Statistical Methods Data were analyzed using SPSS v21.0. Continuous variables were expressed as mean ± SD and compared using Student’s t-test. Categorical variables were analyzed by Chi-square test. p < 0.05 was considered statistically significant. Confidence intervals were calculated at 95%. Data Collection For each participant, demographic data, comorbidities, preoperative serum electrolytes, IPSS score, gland size (measured by ultrasound using formula π/6 × T × AP × L dimension), operative duration, and irrigant volume were recorded. Postoperative serum sodium and potassium levels, vital parameters, and occurrence of any TURP-related complications (TUR syndrome, bleeding, infection) were meticulously documented.

Table 1: Compare the safety & efficacy of bipolar vs monopolar cautery in TURP Outcome GM (n=35) NSB (n=35) Between-group diff (NSB-GM) 95% CI Test & p Resection time, min, mean (SD) 38.37 (8.02) 38.65 (36.38) +0.28 [-12.48, 13.04] Welch t, p=0.965 Irrigant volume, L, mean (SD) 10.94 (3.22) 9.60 (1.88) -1.34 [-2.60, -0.08] Welch t, p=0.038 Post-op hyponatremia (<135 mEq/L), n (%) 27 (77.1%) 15 (42.9%) -34.3 pp [-55.8, -12.8] pp Fisher exact, p=0.0068 Symptomatic TUR syndrome, n (%) 12 (34.3%) 5 (14.3%) -20.0 pp [-39.5, -0.5] pp Fisher exact, p=0.093 Table 1 compares key safety and efficacy parameters between patients who underwent monopolar TURP using glycine (GM) and bipolar TURP using normal saline (NSB). The mean resection time was comparable between the two groups-38.37 ± 8.02 min in GM and 38.65 ± 36.38 min in NSB (p = 0.965)-indicating no statistically significant difference in operative duration. However, the mean irrigant volume used was significantly lower in the bipolar group (9.60 ± 1.88 L) than in the monopolar group (10.94 ± 3.22 L), with a mean difference of -1.34 L (95% CI [-2.60, -0.08]; p = 0.038). This finding demonstrates reduced irrigation requirement and, consequently, a potential decrease in fluid absorption risk with bipolar cautery. In terms of biochemical safety, post-operative hyponatremia (Na⁺ < 135 mEq/L) occurred in 77.1% of GM patients versus 42.9% of NSB patients, showing a significant reduction of -34.3 percentage points (95% CI [-55.8, -12.8]; p = 0.0068) with bipolar resection. Similarly, symptomatic TUR syndrome was less frequent in the bipolar group (14.3%) compared to the monopolar group (34.3%), though this difference did not reach conventional statistical significance (p = 0.093). Table 2: Analyze serum electrolyte changes & clinical relevance Outcome GM (n=35) NSB (n=35) Between-group diff 95% CI Test & p Serum sodium (mEq/L) - Pre; Post (means) 137.68; 132.22 139.54; 135.71 Post-op NSB-GM: +3.49 NA (SD not reported) - Serum potassium (mmol/L) - Post-op mean (SD) 3.80 (0.48) 3.99 (0.46) +0.19 [-0.03, 0.41] Welch t, p=0.095 Fall in potassium, ΔK (mmol/L), mean (SD) 0.25 (0.19) 0.18 (0.46) -0.07 [-0.24, 0.10] Welch t, p=0.410 Hyponatremia (<135 mEq/L) post-op, n (%) 27 (77.1%) 15 (42.9%) -34.3 pp [-55.8, -12.8] pp Fisher exact, p=0.0068 Note: Post-op Na⁺ SDs were not available, so between-group CI/test for post-op Na⁺ means are marked NA. Table 2 details the perioperative changes in serum sodium and potassium levels. Pre-operative sodium values were similar in both groups, but post-operative sodium decreased to 132.22 mEq/L in GM and 135.71 mEq/L in NSB, giving a net difference of +3.49 mEq/L favoring bipolar TURP. Although post-operative SDs were not reported, the decline in sodium was clinically relevant, aligning with the higher incidence of hyponatremia in the monopolar group. For potassium, post-operative mean levels were slightly higher in the bipolar group (3.99 ± 0.46 mmol/L) compared to the monopolar group (3.80 ± 0.48 mmol/L), but this difference was not statistically significant (95% CI [-0.03, 0.41]; p = 0.095). The mean fall in potassium (ΔK) was marginally greater in GM (0.25 ± 0.19 mmol/L) than in NSB (0.18 ± 0.46 mmol/L), though the difference was insignificant (p = 0.410). Table 3 assesses baseline hemodynamic comparability, intra-operative fluid parameters, and complication rates. Pre-operative pulse rate, systolic and diastolic BP, and SpO₂ values were statistically comparable between groups (all p > 0.05), confirming homogeneity at baseline. During surgery, the mean irrigant volume used in GM (10.94 ± 3.22 L) exceeded that in NSB (9.60 ± 1.88 L), with a significant difference of -1.34 L (95% CI [-2.60, -0.08]; p = 0.038), indicating lower fluid exposure in bipolar procedures. The incidence of any intra-operative symptom (e.g., headache, nausea, restlessness) was substantially higher in GM (62.9%) than NSB (20.0%) with a statistically significant risk reduction of -42.9 percentage points (p = 0.00056). Furthermore, confusion, an indicator of moderate TUR syndrome, occurred in 11.4% of GM cases but in none of the NSB cases, suggesting improved neurological safety with bipolar technology, though statistical significance was not reached (p = 0.114). Table 3: Assess intra-/post-operative hemodynamic stability, fluid & complications Outcome GM (n=35) NSB (n=35) Between-group diff (NSB-GM) 95% CI Test & p Baseline pulse, bpm, mean (SD) 76.54 (11.43) 77.28 (12.56) +0.74 [-4.99, 6.47] Welch t, p=0.797 Baseline SBP, mmHg, mean (SD) 121.40 (10.27) 123.97 (11.80) +2.57 [-2.71, 7.85] Welch t, p=0.335 Baseline DBP, mmHg, mean (SD) 72.94 (11.97) 75.14 (11.78) +2.20 [-3.46, 7.86] Welch t, p=0.441 Baseline SpO₂, %, mean (SD) 98.57 (0.78) 98.22 (0.88) -0.35 [-0.75, 0.05] Welch t, p=0.083 Irrigant volume, L, mean (SD) 10.94 (3.22) 9.60 (1.88) -1.34 [-2.60, -0.08] Welch t, p=0.038 Any intra-op symptom, n (%) 22 (62.9%) 7 (20.0%) -42.9 pp [-63.6, -22.1] pp Fisher exact, p=0.00056 Confusion (moderate TUR symptom), n (%) 4 (11.4%) 0 (0.0%) -11.4 pp [-24.3, +1.5] pp Fisher exact, p=0.114 Table 4: Evaluate overall safety & efficacy outcomes (composite view) Outcome GM (n=35) NSB (n=35) Between-group diff (NSB-GM) 95% CI Test & p Symptomatic TUR syndrome, n (%) 12 (34.3%) 5 (14.3%) -20.0 pp [-39.5, -0.5] pp Fisher exact, p=0.093 Any intra-op symptom, n (%) 22 (62.9%) 7 (20.0%) -42.9 pp [-63.6, -22.1] pp Fisher exact, p=0.00056 Irrigant volume, L, mean (SD) 10.94 (3.22) 9.60 (1.88) -1.34 [-2.60, -0.08] Welch t, p=0.038 Resection time, min, mean (SD) 38.37 (8.02) 38.65 (36.38) +0.28 [-12.48, 13.04] Welch t, p=0.965 Table 4 integrates key findings to present a composite overview of safety and efficacy. Symptomatic TUR syndrome and overall intra-operative symptoms were consistently lower in the bipolar group (14.3% and 20.0%, respectively) than in the monopolar group (34.3% and 62.9%), confirming the enhanced safety profile of the bipolar system. The reduction in any intra-operative symptom was statistically highly significant (p = 0.00056). The mean irrigant volume was significantly lower in NSB (9.60 ± 1.88 L vs 10.94 ± 3.22 L, p = 0.038), while resection times remained almost identical (38.65 ± 36.38 min vs 38.37 ± 8.02 min, p = 0.965), confirming equivalent surgical efficiency.

Table 1 - Safety & efficacy (bipolar vs monopolar): Data show no difference in resection time (38.37 vs 38.65 min; p=0.965), while irrigant volume is significantly lower with bipolar (-1.34 L; 95% CI -2.60 to -0.08; p=0.038). Clinically, the standout signal is less post-op hyponatremia with bipolar (42.9% vs 77.1%; p=0.0068). Symptomatic TUR syndrome also trends lower (14.3% vs 34.3%; p=0.093). This overall pattern mirrors multiple RCTs and meta-analyses where bipolar TURP in saline achieves equivalent efficacy to monopolar but improves fluid/electrolyte safety by avoiding hypotonic glycine and limiting dilutional hyponatremia Singh H et al.(2005)[6]. Reductions in TUR-syndrome-related symptoms and electrolyte derangements with bipolar have also been repeatedly noted Ho HS et al.(2007)[7]. The lower irrigation requirement observed is directionally consistent with prior reports of either similar or reduced irrigant use and transfusion rates with bipolar systems, especially in larger glands or longer resections Hirik E et al.(2015)[8]. One caution for interpretation: the very large SD on NSB resection time suggests dispersion/recording heterogeneity; nonetheless, even with that variance, there’s no time penalty for bipolar-matching guideline-level summaries that consider bipolar non-inferior in efficiency Singhania P et al.(2010)[9]. Table 2 - Serum electrolyte changes & clinical relevance: Both groups show a sodium fall, but post-op Na⁺ is ~3.5 mEq/L higher with bipolar (135.71 vs 132.22 mEq/L). Although SDs for post-op Na⁺ aren’t available (so a formal between-group test can’t be computed), the concordant reduction in hyponatremia prevalence (Table 1 & Table 2) strengthens the biological plausibility that bipolar mitigates dilutional hyponatremia-an effect widely reported when 0.9% saline replaces 1.5% glycine Skolarikos A et al.(2016)[10]. For potassium, post-op K⁺ is slightly higher with bipolar (+0.19 mmol/L; p=0.095) and the ΔK is modestly smaller (-0.07 mmol/L; p=0.410); neither reaches significance. Prior trials similarly show minimal, clinically unimportant K⁺ shifts between modalities, with safety differences driven primarily by sodium/osmolality rather than potassium handling Giulianelli R et al.(2013)[11]. Overall, electrolyte findings align with the mechanistic advantage of bipolar energy in saline irrigant-lower risk of TUR syndrome via better sodium/osmolality stability Neyer M et al.(2013)[12]. Table 3 - Hemodynamic stability, fluid & complications: Baseline vitals (pulse, SBP/DBP, SpO₂) are well balanced (all p>0.05), supporting internal validity for causal contrasts-a point emphasized in earlier RCTs that matched pre-op hemodynamics Pradhan MM et al.(2020)[13]. Intraoperatively, irrigant volume is lower with bipolar (-1.34 L; p=0.038), and any intra-op symptom (headache, nausea, restlessness) is far less common (20.0% vs 62.9%; p=0.00056). Prior studies attribute these differences to reduced fluid absorption and stable tonicity with saline, translating to fewer neurologic and cardiovascular manifestations of TUR syndrome Yip SK et al.(2011)[14]. The absence of confusion in the bipolar arm (0% vs 11.4%; p=0.114) echoes a directional safety trend repeatedly seen in the literature, often reaching significance in larger series or pooled estimates Otaola-Arca H et al.(2020)[15]. Collectively, hemodynamic/clinical data reinforce the safety edge of bipolar systems under standard irrigation heights and routine spinal anesthesia settings. Table 4 - Composite view (overall safety & efficacy): The composite endpoints consolidate the story: symptomatic TUR syndrome and any intra-op symptom are both lower with bipolar, irrigant volume is significantly lower, and resection time is equivalent. This precisely matches the consensus from high-quality evidence syntheses: bipolar TURP provides non-inferior efficacy with superior perioperative safety, mainly via electrolyte stability and lower clinically relevant symptom burden Kwon JS et al.(2011)[16]. From a practice standpoint, results support preferring bipolar in patients at risk for fluid absorption or electrolyte shifts (e.g., larger prostates, prolonged resections, cardiac/renal comorbidity), while not sacrificing operative efficiency-a balance emphasized in guideline narratives and pragmatic trials Issa MM. (2008)[17].

The present study, demonstrates that bipolar TURP offers superior safety with comparable efficacy when compared to conventional monopolar TURP. Although operative time and overall resection efficiency were similar between the two groups, bipolar resection required significantly less irrigant volume and showed a marked reduction in post-operative hyponatremia. The absence of significant electrolyte imbalance and a lower incidence of TUR-syndrome-related symptoms in the bipolar group confirm its clinical advantage. These findings are consistent with several international studies that support bipolar technology as a safe, effective, and patient-friendly alternative, especially in high-risk patients or those with larger prostates. Hence, bipolar cautery can be considered the preferred modality for transurethral resection of the prostate, combining the efficacy of traditional TURP with enhanced perioperative safety.

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