Impact of Regional Hypothermia on Urinary Continence and Potency After Robot-Assisted Radical Prostatectomy

Feasibility study of a novel rectal cooling system for hypothermic radical prostatectomy in a swine model

Thermal damage and inflammatory responses of the sphincter and neurovascular bundles (NVBs) are responsible for post-prostatectomy incontinence and erectile dysfunction. Intraoperative hypothermia in the pelvic cavity may reduce the occurrence of these complications. We evaluated the feasibility of a novel rectal cooling system using an animal model. A novel rectal cooling system consisting of a cooling console and a multi-lumen rectal balloon was developed. We conducted animal tests on male pigs to evaluate the efficacy and safety of the system. The primary endpoint was to maintain the temperature of the NVBs at 25℃ (±5℃) during and after the electrocauterization of the bladder neck for 10 seconds. The safety endpoint was device-related complications or significant changes in the core body temperature of the pigs. The NVB temperature was below 30℃ within 3 minutes of activation of the rectal balloon. The temperature of the proximal NVB was consistently maintained below 25℃ in all cases. The temperature 1 cm from the bladder neck did not rise above 38°C and dropped to the initial level within 1 minute after electrocauterization. During cooling, the minimum temperature at the apex of the prostate was reduced to 10.1℃. There were no device-related complications or significant changes in core body temperature throughout the experiment. Animal tests suggest the feasibility and safety of this novel rectal cooling system. A first-in-human trial to assess the safety and efficacy of this system during radical prostatectomy is warranted.

Anatomical robotic prostatectomy: technical factors to achieve superb continence and erectile function

Debate continues as to the superiority of robotic versus open radical prostatectomy for the surgical treatment of localized prostate cancer. Despite this controversy, retrospective data from high volume centres has demonstrated RARP is associated with improved pentafecta outcomes with lower transfusion rates, less incontinence, lower positive surgical margins and improved potency. Advocates of robotic assisted radical prostatectomy (RARP) believe an enhanced visual field, the precision afforded by robotic technology as well as lack of bleeding, sharp dissection and delicate tissue handling lead to improved outcomes. Prostate Cancer is the second most common cancer diagnosed in men, and as the number of post-surgical patients increases, the complications of urinary incontinence and erectile dysfunction not only have a significant negative impact on patients' quality of life, but have become an expanding part of clinical practice. This article outlines what are believed to be the most important strategies based on anatomical knowledge and technical expertise, that allow robotic prostatectomists to achieve superb outcomes in urinary and erectile function.

A Randomized Control Trial Of Anti-Inflammatory Regional Hypothermia On Urinary Continence During Robot-Assisted Radical Prostatectomy

The present study seeks to present a single-blind, randomized control trial of a hypothermic anti-inflammatory device, the endorectal cooling balloon (ECB), to assess whether regional hypothermia could improve 90-day and time to pad-free continence following robot-assisted radical prostatectomy (RARP). Five high-volume surgeons at three institutions had patients randomized (1:1) to regional hypothermia with ECB versus control. Patients were blinded to device use, as it was inserted and removed intraoperatively. Knowledge of device use was restricted to the operating room personnel only; recovery room and ward nursing staff were not informed of device use and instructed to indicate such if a patient inquired. An independent and blinded data acquisition contractor assessed outcomes via components of the EPIC and IPSS. The primary outcome was categorical pad-free continence at 90-days and the secondary outcome was a Kaplan-Meier time-to pad-free continence at 90 days. 100 hypothermia and 99 control patients were included. The primary outcome of 90-day pad-free continence was 50.0% (27.8-70.0%) in the hypothermia group versus 59.2% (33.3-78.6%) in the control (p = 0.194). The secondary outcome of Kaplan Meier analysis for time to 90-day continence was not statistically significant. At one year, there were also no statistically significant differences in continence recovery. Post-hoc analysis revealed a trend towards improvement in continence in one of three sites. Overall, the trial demonstrated no benefit to regional hypothermia either in our primary or secondary outcomes. It is suggested that surgical technique and prevention of surgical trauma may be more advantageous to improving continence recovery.

Neuroprotective and Nerve Regenerative Approaches for Treatment of Erectile Dysfunction after Cavernous Nerve Injury

Erectile dysfunction (ED) is a significant cause of reduced quality of life in men and their partners. Cavernous nerve injury (CNI) during pelvic surgery results in ED in greater than 50% of patients, regardless of additional patient factors. ED related to CNI is difficult to treat and typically poorly responsive to first- and second-line therapeutic options. Recently, a significant amount of research has been devoted to exploring neuroprotective and neuroregenerative approaches to salvage erectile function in patients with CNI. In addition, therapeutic options such as neuregulins, immunophilin ligands, gene therapy, stem cell therapy and novel surgical strategies, have shown benefit in pre-clinical, and limited clinical studies. In the era of personalized medicine, these new therapeutic technologies will be the future of ED treatment and are described in this review.

Chitosan membranes applied on the prostatic neurovascular bundles after nerve-sparing robot-assisted radical prostatectomy: a phase II study

OBJECTIVE

To evaluate the feasibility and the safety of applying chitosan membrane (ChiMe) on the neurovascular bundles (NVBs) after nerve-sparing robot-assisted radical prostatectomy (NS-RARP). The secondary aim of the study was to report preliminary data and in particular potency recovery data.

PATIENTS AND METHODS

This was a single-centre, single-arm prospective study, enrolling all patients with localised prostate cancer scheduled for RARP with five-item version of the International Index of Erectile Function scores of >17, from July 2015 to September 2016. All patients underwent NS-RARP with ChiMe applied on the NVBs. The demographics, perioperative, postoperative and complications data were evaluated. Potency recovery data were evaluated in particular and any sign/symptom of local allergy/intolerance to the ChiMe was recorded and evaluated.

RESULTS

In all, 140 patients underwent NS-RARP with ChiMe applied on the NVBs. Applying the ChiMe was easy in almost all the cases, and did not compromise the safety of the procedure. None of the patients reported signs of intolerance/allergy attributable to the ChiMe and potency recovery data were encouraging.

CONCLUSION

In our experience, ChiMe applied on the NVBs after NS-RARP was feasible and safe, without compromising the duration, difficulty or complication rate of the 'standard' procedure. No patients had signs of intolerance/allergy attributable to the ChiMe and potency recovery data were encouraging. A comparative cohort would have added value to the study. The present paper was performed before Conformité Européene (CE)-mark achievement.

Hypothermic Cooling Measured by Thermal Magnetic Resonance Imaging; Feasibility and Implications for Virtual Imaging in the Urogenital Pelvis

OBJECTIVE

To study the combination of thermal magnetic resonance imaging (MRI) and novel hypothermic cooling, via an endorectal cooling balloon (ECB), to assess the effective dispersion and temperature drop in pelvic tissue to potentially reduce inflammatory cascade in surgical applications.

METHODS

Three male subjects, before undergoing robot-assisted radical prostatectomy, were cooled via an ECB, rendered MRI compatible for patient safety before ECB hypothermia. MRI studies were performed using a 3T scanner and included T2-weighted anatomic scan for the pelvic structures, followed by a temperature mapping scan. The sequence was performed repeatedly during the cooling experiment, whereas the phase data were collected using an integrated MR-high-intensity focused ultrasound workstation in real time. Pelvic cooling was instituted with a cooling console located outside the MRI magnet room.

RESULTS

The feasibility of pelvic cooling measured a temperature drop of the ECB of 20-25 degrees in real time was achieved after an initial time delay of 10-15 seconds for the ECB to cool. The thermal MRI anatomic images of the prostate and neurovascular bundle demonstrate cooling at this interface to be 10-15 degrees, and also that cooling extends into the prostate itself ~5 degrees, and disperses into the pelvic region as well.

CONCLUSION

An MRI-compatible ECB coupled with thermal MRI is a feasible method to assess effective hypothermic diffusion and saturation to pelvic structures. By inference, hypothermia-induced rectal cooling could potentially reduce inflammation, scarring, and fistula in radical prostatectomy, as well as other urologic tissue procedures of high-intensity focused ultrasound, external beam radiation therapy, radioactive seed implants, transurethral microwave therapy, and transurethral resection of the prostate.

Investigation of factors affecting hypothermic pelvic tissue cooling using bio-heat simulation based on MRI-segmented anatomic models

This study applied a simulation method to map the temperature distribution based on magnetic resonance imaging (MRI) of individual patients, and investigated the influence of different pelvic tissue types as well as the choice of thermal property parameters on the efficiency of endorectal cooling balloon (ECB). MR images of four subjects with different prostate sizes and pelvic tissue compositions, including fatty tissue and venous plexus, were analyzed. The MR images acquired using endorectal coil provided a realistic geometry of deformed prostate that resembled the anatomy in the presence of ECB. A single slice with the largest two-dimensional (2D) cross-sectional area of the prostate gland was selected for analysis. The rectal wall, prostate gland, peri-rectal fatty tissue, peri-prostatic fatty tissue, peri-prostatic venous plexus, and urinary bladder were manually segmented. Pennes' bioheat thermal model was used to simulate the temperature distribution dynamics, by using an in-house finite element mesh based solver written in MATLAB. The results showed that prostate size and periprostatic venous plexus were two major factors affecting ECB cooling efficiency. For cases with negligible amount of venous plexus and small prostate, the average temperature in the prostate and neurovascular bundles could be cooled down to 25 °C within 30 min. For cases with abundant venous plexus and large prostate, the temperature could not reach 25 °C at the end of 3 h cooling. Large prostate made the cooling difficult to propagate through. The impact of fatty tissue on cooling effect was small. The filling of bladder with warm urine during the ECB cooling procedure did not affect the temperature in the prostate or NVB. In addition to the 2D simulation, in one case a 3D pelvic model was constructed for volumetric simulation. It was found that the 2D slice with the largest cross-sectional area of prostate had the most abundant venous plexus, and was the most difficult slice to cool, thus it may provide a conservative prediction of the cooling effect. This feasibility study demonstrated that the simulation tool could potentially be used for adjusting the setting of ECB for individual patients during hypothermic radical prostatectomy. Further studies using MR thermometry are required to validate the in silico results obtained using simulation.

Preserving continence during robotic prostatectomy

Preservation of postoperative urinary continence remains the primary concern of all men and their surgeons following robot-assisted radical prostatectomy (RARP). Without doubt, continence is the most important quality of life issue following radical prostatectomy. Identification of difficulties and lessons learned over time has helped focus efforts in order to improve urinary quality of life and continence. This review will examine definitions of continence and urinary quality of life evaluation, technical aspects and the impact of patient-related factors affecting time to and overall continence.

Robotic-assisted radical prostatectomy after the first decade: surgical evolution or new paradigm

Early studies indicate that robotic-assisted radical prostatectomy (RARP) has promising short-term outcomes; however, RARP is beyond its infancy, and the long-term report cards are now beginning. The important paradigm shift introduced by RARP is the reevaluation of the entire open radical prostatectomy experience in surgical technique by minimizing blood loss and complications, maximizing cancer free outcomes, and a renewed assault in preserving quality of life outcomes by many novel mechanisms. RARP provides a new technical “canvas” for surgical masters to create upon, and in ten years, has reinvigorated a 100-year-old “gold standard” surgery.

The application of regional hypothermia using transrectal cooling during radical prostatectomy: mitigation of surgical inflammatory damage to preserve continence

Preservation of continence and sexual function continues to be a formidable quality-of-life issue regarding outcomes after radical prostatectomy. There is little argument that physical preservation of the nerves and sphincters is a critical component to achieving success in these domains. Previously demonstrated factors such as advancing age, deteriorating physical health status, and subnormal baseline potency negatively impact outcomes. Our hypothesis, however, has been that inflammatory response to surgery has a large impact on surgical outcomes of prostatectomy. Trauma-induced inflammation could account for variation in recovery despite nearly identical surgery on many patients, especially in high-volume surgeons. In other words, we suggest and maintain that younger and healthier patients tolerate and/or recover better from the trauma/inflammation of surgery. Those who do not recover as well may have altered inflammatory response to injury. A common response to decrease inflammation in response to physical injury would be as simple as to cool the injury with ice. Previous neurologic studies have suggested that using ice during surgical intervention can reduce the inflammatory damage. Therefore, we applied this concept that preemptive hypothermia could reduce inflammation to the robot-assisted prostatectomy procedure to potentially lead to improved continence and potency outcomes. In 2009, we introduced the concept of regional hypothermia via an endorectal cooling balloon during robot-assisted radical prostatectomy (RARP). We have published our single institution data demonstrating a significant reduction of overall incontinence. Defining continence as zero-pads, our overall 1-year incontinence has been reduced by 70% (from 13% to 4%). Severe incontinence, defined as two or more pads, was likewise reduced by 70% (from 2.9% to 0.9%). Regional hypothermia used during the time of surgery represents a novel strategy for minimizing inflammation and subsequent muscle and nerve damage in RARP.

Critical review of 'pentafecta' outcomes after robot-assisted laparoscopic prostatectomy in high-volume centres

• Historically, the ideal outcome of radical prostatectomy (RP) has been measured by achievement of the so-called 'trifecta', or the concurrent attainment of continence and potency with no evidence of biochemical recurrence. However, in the PSA era, younger and healthier men are more frequently diagnosed with prostate cancer. Such patients have higher expectations from the advanced minimally invasive surgical technologies. Mere trifecta is no longer an ideal outcome measure to meet the demands of such patients. • Keeping the limitations of trifecta in mind, we have earlier proposed a new method of outcomes analysis, called the 'pentafecta', which adds early complications and positive surgical margins (PSMs) to trifecta. • We performed a Medline search for articles reporting the complications, PSM rates, continence, potency and biochemical recurrence after robot-assisted RP. Related articles were selected and individual outcomes were reviewed.

Basis for the use of localized hypothermia during radical pelvic surgery

Controlled tissue cooling, or hypothermia, has been used therapeutically for decades to mitigate the negative effects of traumatic, ischemic, and surgical insults. When applied systemically, moderate hypothermia can attenuate or prevent the extent of neurologic sequelae. Localized hypothermia, on the other hand, has the capacity to reduce tissue edema, suppress inflammation, and minimize the severity of peripheral nerve injury. Therapeutic hypothermia has been used in critical care, neurosurgery, ophthalmology, otolaryngology, cardiothoracic surgery and most recently in urology. Nerve injury during radical pelvic surgery can result in urinary incontinence or retention, impotence and bowel dysfunction. Localized hypothermia during radical prostatectomy has demonstrated improved recovery of urinary continence and erectile function, and similar benefits might be observed in other types of radical pelvic surgery.