Bipolar versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis



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ORIGINAL ARTICLE versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis Acuña-López JA, 1 Hernández-Torres AU, 1 Gómez-Guerra LS, Martínez-Montelongo R, 3 Lozano-Salinas JF. 3 Abstract Objective: To analyze the possible advantages of bipolar and conventional monopolar transurethral resection of the prostate during surgical intervention for prostatic hyperplasia in both the intraoperative and immediate postoperative periods. Methods: A cross-sectional analytical study was carried out on 15 patients operated on with Gyrus ACMI bipolar resector and 15 with monopolar resector. Results: Mean age was 7. years in the monopolar group and.1 years in the bipolar group. Bleeding during the cutting was classified as moderate-abundant in % of patients in the monopolar group vs % in the bipolar group (P <.5). Clotting capacity was very good-excellent in 1% of the monopolar group vs 7% in the bipolar group (P <.5). The degree of fragment adherence to resecting blade was moderate-abundant in 1% of the monopolar group vs % of the bipolar group (P <.5). There was no statistical significance in the remaining variables compared. Conclusions: In the authors experience, bipolar transurethral resection of the prostate presents with less fragment adherence and bleeding during cutting thus Resumen Objetivo: Analizar las posibles ventajas que ofrece la Resección Transuretral Prostática frente a la Resección Transuretral Prostática o convencional durante la intervención quirúrgica por hiperplasia prostática, tanto en el periodo transoperatorio como en el posoperatorio inmediato. Método: Estudio descriptivo analítico en 15 pacientes que fueron intervenidos con resector bipolar Gyrus ACMI y 15 con resector monopolar. Resultados: La edad media fue de 7, años en el grupo monopolar frente,1 años en el grupo bipolar; el volumen ecográfico prostático fue de 5. cc vs 9. cc. El sangrado durante el corte se calificó como moderadoabundante en % monopolar vs % bipolar (p <.5). La capacidad de coagulación fue notable-excelente en el 1% del tratamiento monopolar vs 7% tratamiento bipolar (p <.5). El grado de adherencia de fragmentos al asa fue moderado-abundante en el 1% monopolar vs % bipolar (p <.5). No hubo diferencias significativas en el resto de las variables comparadas. Conclusiones: En nuestra experiencia, la resección transuretral de próstata bipolar presenta menor adherencia de 1Resident. Head of Urology Service. 3Staff Physician. Urology Service of the Hospital Universitario Dr. José Eleuterio González. Universidad Autónoma de Nuevo León. Monterrey, N.L., Mexico. Corresponding author: Dr. Juan Antonio Acuña Lopez. Servicio de Urología, Hospital Universitario Dr. José Eleuterio González, UANL. Avenida Francisco I. Madero y Avenida Gonzalitos S/N. Colonia Mitras Centro, CP. Monterrey, Nuevo León, México. Direct Telephone and Fax; 1(1) 3331713. Email: juan.acuna@urologiahu.org.mx 1 Rev Mex Urol 1;7(3):1-151

Acuña-López JA, et al. versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis improving intraoperative visibility for the surgeon. Both procedures present with similar postoperative results. Key words: transurethral resection of the prostate, bipolar, monopolar, Mexico. fragmentos y una buena capacidad de coagulación durante el corte, lo cual mejora la visibilidad para el cirujano durante el transoperatorio, ambos presentan resultados similares posoperatorios. Palabras claves: Resección transuretral de próstata, bipolar, monopolar, México. INTRODUCTION There are numerous treatments available to patients presenting with obstructive urinary symptoms secondary to prostatic hyperplasia that include conservative management, pharmacological therapy, transurethral resection and open prostatectomy. Despite the everincreasing use of medical treatments a significant proportion of patients still require surgical treatment. 1 Even with the advances in minimally invasive therapy, transurethral resection of the prostate (TURP) continues to be the criterion standard for those prostate adenomas that can be resected in approximately one hour due to their volume. One of the instruments designed to reduce TURP morbidity is the bipolar scalpel. It cuts and establishes hemostasis at the same time, using physiological solution for irrigation. Working with this solution instead of hypoosmolar solutions (glycine) reduces the possibility of TUR syndrome.,3 This syndrome is the result of fluid absorption that then causes dilutional hyponatremia and fluid intoxication. During the endourological procedure one of the functions of liquid irrigation is to improve visibility. Fluid pressure should be equal to or greater than that caused by resected tissue bleeding. In turn, liquid passes over open capillaries entering the bloodstream and causing a hypervolemic state with dilutional hyponatremia. 3 At the same time TURP frequently requires extended transurethral catheterization and variable hospital stay in addition to being associated with distinct complications such as bleeding, urinary incontinence, erectile dysfunction and bladder neck stenosis. 1,3-5 The objective of the present study is to analyze possible advantages of bipolar (Gyrus) TURP over conventional monopolar TURP during surgical intervention for prostatic hyperplasia and in immediate postoperative period. METHODS A randomized (one-to-one) prospective study was carried out on 3 patients during the time frame of August to January 9. Patients had been diagnosed with benign prostatic hyperplasia (BPH) and presented with ultrasound (US) prostate volume between and cc. A group of fifteen patients were operated on with conventional monopolar resector, F sheath and 3 optic using glycine solution. Another group of 15 patients were operated on with Gyrus ACMI resector, W generator and -1 V coagulation voltage, F sheath, 3 optic using continuous irrigation with physiological solution. All anticoagulated patients were excluded from the study as well as patients presenting with neurogenic bladder and those suspected of or diagnosed with prostate adenocarcinoma. Platelet antiaggregant medication was suspended two weeks prior to surgery in those patients receiving it. All patients were given a single intravenous dose of mg ciprofloxacin as antibiotic prophylaxis immediately before beginning procedure. Resection technique was the same in all patients: once the presence of bladder tumor was discarded prostate resection with the Nesbit technique was performed. When procedure was completed hemostatic revision was carried out, fragments were extracted with an Ellik evacuator, and 3-way F Foley catheter was put in place. Balloon was inflated with cc physiological solution and there was continuous irrigation at 1 cc of injectable water every hours. The study was carried out by surgeons. Each of them filled out a questionnaire at the end of each surgery Rev Mex Urol 1;7(3):1-151 17

Acuña-López JA, et al. versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis Table 1. Patient characteristics of bo. Table. Intraoperative variable results. Mean ± standard Mean ± standard USG volume (g).1 ± 9.5 7 ±.9 Volumen ecográfico (g) 9. ± 17.1 5. ± 1. PSA (ng/ml).1 ± 3.5 5.7 ± 3. Preoperative hematocrit (%).1 ±.9 3.9 ±. Preoperative serum sodium (meq/l) 139.9 ± 3 13 ± 3.39 In all variables P >.5. Cutting capacity (excellent-very good) Intraoperative visibility (excellent-very good) Degree of fragment adherence to blade (abundant-moderate) Bleeding during cutting (abundant-moderate) Bleeding during cutting (moderate-abundant) p 93.3% 1% >.5.% 73.3% >.5 7% 1% <.5 % 1% <.5.%.% <.5 1 1 Bad Good Very good Excellent 1 1 Bad Good Very good Excellen Image 1. Cutting capacity in both groups. Image. Intraoperative visibility. to subjectively evaluate 5 parameters: resector cutting capacity (excellent-very good-good-bad), intraoperative visibility (excellent-very good-good-bad), coagulation capacity (excellent-very good-good-bad), degree of fragment adherence to resecting blade (very abundantabundant-moderate-scarce-none) and bleeding during cutting (very abundant-abundant-moderate-scarce-none). In addition resection time, volume resected, days of wash, days with catheter, hospital stay in days, hematocrit reduction, transfusion necessity, serum sodium reduction and episodes of acute urine retention after bladder catheter removal were all evaluated. Results were analyzed with the STATA-IC-1- statistical pack, license INTERMED--191-531-ECE, and with programs that were developed in the authors hospital. Student t test was used to contrast means and percentages were compared using non-parametric tests and chi-square test. -9 Differences were considered to be significant when P <.5. RESULTS Table 1 shows the distribution of both groups. Data for each resector is described. Mean age for the monopolar group was 7. years and for the bipolar group was.1 years. Mean US volume for the monopolar group was 5. g and 9. g for the bipolar group. Mean PSA was 5.7 ng/ml for the monopolar group and.1 ng/ml for the bipolar group. Table summarizes intraoperative characteristic results with each resector. Cutting capacity was classified as excellent-very good in 1% of cases in the monopolar group and as excellent-very good in 93% of cases in the bipolar group (P >.5) (Image 1). Intraoperative visibility was classified as excellent-very good in 73% of cases in the monopolar group and as excellent-very good in % of the bipolar group, and P >.5 (Image ). There was significant difference in favor of the bipolar resector in relation to degree of fragment adherence to resecting blade and was classified as 1 Rev Mex Urol 1;7(3):1-151

Acuña-López JA, et al. versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis 1 1 1 None Scarce Moderate Abundant Very abundant 1 1 1 Bad Good Very good Excellent Image 3. Degree of adherence classification in both groups. Imagen. Coagulation capacity classification in both groups. 1 9 7 5 3 1 None Scarce Moderate Abundant Very abundant Image 5. Classification of degree of bleeding during cutting in both groups. abundant-moderate in 1% of cases in the monopolar group and only % of cases in the bipolar group and P <.5 (Image 3). In contrast, significant results were obtained in favor of the monopolar resector in regard to coagulation capacity and was classified as excellentvery good in 1% of cases in the monopolar group and 7% of cases in the bipolar group and P <.5 (Image ). Bleeding during cutting was classified as abundantmoderate in % of cases in the monopolar group and a favorable % of cases in the bipolar group with P<.5 (Image 5). Table 3 summarizes variables analyzed in the postoperative period. No significant difference were found in relation to days of wash (1.13 vs.9) with P>.5; days with bladder catheter (7. vs.5) (catheterization was prolonged due to the necessity to admit patients for treatment of other urological disorders, and so study patients were released with transurethral catheter that was removed in consultation Table 3. Postoperative results. In all variables P >.5 Mean ± standard Mean ± standard Volume resected (g) 13.9 ± 7. 17. ± 5.7 Resection duration (min).3 ± 19. 1 ± 13.5 Bladder catheter (days).5 ± 3. 7. ± 1.5 Days of wash.9 ±.35 1.13 ±.35 Hospital stay (days) 1. ±. 1. ±.5 Postoperative serum sodium (meq/l) 139. ±. 1.1 ± 3. Changes in serum sodium (meq/l).7 ± 3.1. ± 5.1 Postoperative hematocrit(%) 3.5 ± 3.5 39.7 ± 3. Changes in hematocrit (%) 3. ± 1..1 ±.7 Urinary retention episodes 1 Clot evacuation 1 once urine was clear); hospital stay was evaluated in days (1. vs 1.). No differences were found in relation to hematocrit reduction after surgery (.1 points vs 3. points) or serum sodium reduction (. meq/l vs.7 meq/l). No patient required blood transfusion nor were there any cases of TUR syndrome. There was one episode of acute urine retention after transurethral catheter removal in the monopolar group that was managed with catheter repositioning and removal hours later. Further retention did not present in Rev Mex Urol 1;7(3):1-151 19

Acuña-López JA, et al. versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis that patient. Clot evacuation had to be carried out on a patient in the monopolar group hours after surgery. One patient from the bipolar group presented with a prostate volume of cc and a change to monopolar resection had to be made due to bipolar resector inadequate clotting. DISCUSSION The goals of BPH therapy are to improve quality of life, reduce symptoms and minimize secondary effects. 1,1 Different treatment options include conservative treatment, pharmacological therapy, minimally invasive procedures, and surgery. Different factors determine treatment options such as urinary symptom relevance, age, patient self-sufficiency and status, among others. Even though the need for surgery has been on the decline for the past few years and different medical treatments have been described, TURP continues to be the criterion standard among minimally invasive procedures. TURP mortality remains under.5%. However, currently intraoperative complications are common: blood loss, with a.5-.% transfusion rate, and TUR syndrome present in % of cases if resection time is greater than 9 minutes and.5% if it is less than that amount of time.,11,1 New resection equipment with bipolar energy attempts to avoid this morbidity by carrying out cutting and hemostasis at the same time through the use of physiological solution as continuous irrigation liquid. The present authors analyzed variables that can have repercussions in TURP duration and quality, such as fragment adherence to the resecting blade and bleeding during cutting. The evaluation of these two variables favored the bipolar resector while the monopolar resector demonstrated a distinct advantage in relation to coagulation capacity. The fact that bipolar energy offers simultaneous cutting and clotting probably reduces clotting capacity in and of itself. Even so, it is important to mention that the monopolar equipment showed the advantage in this capacity. This subjective classification was carried out by two different surgeons. One episode of acute urinary retention presented in the monopolar group after transurethral catheter removal. Different reports have evaluated the bipolar resector. In 5 Starkman et al reported on a series of 3 patients in whom transurethral catheter was removed at a mean 1. days in the bipolar group and a mean 3. days in the monopolar group. Four out of eighteen patients that underwent TURP with monopolar resector presented with urine retention as did 3 out of 5 patients that underwent TURP with bipolar resector. Abascal Junquera et al () reported on a series of 5 in whom transurethral catheter was removed in 3.1 days in the monopolar group and in.9 days in the bipolar group. Acute urine retention presented in only 1 patient in the monopolar group. There were no significant differences in hematocrit or serum sodium reduction. Marco de Sio et al () 11 reported on a series presenting significant differences in relation to catheterization duration: catheter was removed at 7 hours in patients with bipolar resection and at 1 hours in the monopolar group. No patients presented with urine retention and no differences were found in relation to hematocrit and serum sodium reduction. These last two groups presented differences in relation to surgery duration when compared with the present study, most likely due to prostate volume of this study s patients. It is also important to mention that 5% of tissue resected with Gyrus bipolar equipment was vaporized, thus presenting with lower volume at the time of resected material evaluation. 1,13 Henry S.S. Ho et al (7) 1 presented results of 1 patients in the comparison of monopolar vs bipolar resector. Two groups were formed, one of 5 patients and the other of. Both groups presented with similar results in regard to surgery duration, amount of resected tissue and hemoglobin reduction. There were only significant differences in serum sodium reduction and patients presented with TUR syndrome. 1 In the present study, the change in serum sodium and hematocrit was not significant. No patient presented with serum sodium under 135 meq/l prior to surgery, which reduced risk of presenting with irrigation liquid reabsorption syndrome. The results of the present study show the bipolar resector to be equivalent to the conventional monopolar resector in reference to the intra- and postoperative variables studied. Certain advantages for both groups are suggested due to the small number of cases, therefore it is recommendable to increase the number of patients in order to determine the existence of significant differences. CONCLUSIONS In the present authors experience TURP with Gyrus bipolar resector offered better coagulation during cutting and less fragment adherence to the resecting blade, enabling the surgeon to carry out a simpler resection. Even so, the monopolar resector was shown to be advantageous with respect to coagulation when considered alone. Postoperative results were similar in the two groups. 15 Rev Mex Urol 1;7(3):1-151

Acuña-López JA, et al. versus monopolar transurethral resection of the prostate: intraoperative and postoperative result analysis Bibliography 1. Yoon CJ, Kim JY, Moon KH, et al. Transurethral Resection Of the Prostate with a Tissue Management System Compared to Conventional Resectoscope: One Year Outcome. Yonsei Med J ;7(5):715-7.. Abascal-Junquera JM, Cecchini-Rosell L, Salvador-Lacambra C. Resección transuretral de próstata bipolar vs monopolar: análisis peroperatorio de los resultados. Actas Urol Esp ;3(7):1-. 3. Martis G, Cardi A, Massimo D, Ombres M. Transurethral resection of prostate: technical progress and clinical experience using the bipolar Gyrus plasmakinetic tissue management system. Surg Endosc ;(9):7-3.. Starkman J, Santucci R. Comparison of bipolar transurethral resection of the prostate with standard transurethral prostatectomy: shorter stay, earlier catheter removal and fewer complications. BJU Int 5;95(1):9-71. 5. Cárdenas Estrada Eloy, Ríos Briones Nidia Isabel, Pérez Chávez Fernando. Programa matemático para el cálculo de tamaño de la muestra, en ambiente excel microsoft. XXIII Congreso Nacional de Investigación Biomédica. Facultad de Medicina, U.A.N.L., Monterrey, México, 5;7-9.1.. Pagano, Marcello. Gauvreau, Kimberlee. Principles of Biostatistics. th Ed. Duxbury.. USA. 7. Cárdenas Estrada Eloy. Programa de calculos estadísticos para computadoras tipo personal. XI Encuentro de Investigación Biomédica. Facultad de Medicina, U.A.N.L. Monterrey, México. 1993, 1.1.. Cárdenas Estrada Eloy, Ríos Briones Nidia Isabel, et al. Programa matemático para el cálculo de X (CHI AL CUADRADO), como complemento al paquete de operaciones estadísticas del programa Excel de Microsoft. XXI Congreso Nacional de Investigación Biomédica. Facultad de Medicina, U.A.N.L., Monterrey, México, 3, -.1. 9. Cárdenas Estrada Eloy, Ríos Briones Nidia Isabel, Bosques Padilla Francisco Javier, Decrescenzo Tancredo Francisco, Galarza Delgado Dionisio, Cárdenas Montemayor Eloy. Programa matemático para el cálculo de pruebas de distribución t en ambiente excel microsoft, utilizando datos Agrupados. XXII Congreso Nacional de Investigación Biomédica. Facultad de Medicina, U.A.N.L., Monterrey, México,, -.1. 1. Ho HS, Cheng CW. transurethral resection of prostate: a new reference standard? Curr Opin Urol ;1(1):5-55. 11. de Sio M, Autorino R, Quarto G, et al. Gyrus bipolar versus standard monopolar transurethral resection of the prostate: a randomized prospective trial. Urology ;7(1):9-7. 1. Barrero-Candau R, Sánchez-Zalabardo JM, Blasco-Beltrán B. Transurethral prostatic resection with bipolar scalpel. Actas Urol Esp ;():17-151. 13. Jaime DR, Arrambide GG, Gutiérrez GA. Estudio Prospectivo, comparativo, entre resección transuretral de próstata vs electrovaporización. Reporte preliminar. Rev Mex Urol ;(3):1-13. 1. Ho HS, Yip SK, Lim KB. A prospective randomized study comparing monopolar and bipolar transurethral resection of prostate using transurethral resection in saline (TURIS) system. Eur Urol 7;5():517-5 Rev Mex Urol 1;7(3):1-151 151