Intraoperative Neuromonitoring of Pelvic Autonomous Nerve Plexus During Total Mesorectal Excision

Rectal Neoplasms Clinical Trial

Official title:

Intraoperative Neuromonitoring of Pelvic Autonomous Nerve Plexus During Total Mesorectal Excision

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT04949646
• Other study ID #: PelIONM
• Status: Recruiting
• Phase: N/A
• Start date: September 19, 2021
• Est. completion date: September 19, 2027

Study information

• Verified date: March 2024
• Source: Larissa University Hospital
• Contact: Konstantinos Tepetes, Prof
• Phone: 00302413502804
• Email: tepetesk[@]gmail.com
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this research protocol is the evaluation of the improvement of the anorectal and urogenital urinary function, alongside the postoperative quality of life after the application of pIONM in patients submitted to TME for rectal cancer.

Description:

The introduction of Total Mesorectal Excision (TME) resulted to the improvement of the overall survival and local recurrence rates of rectal cancer patients. However, the associated urogenital and anorectal functional deficit has a significant effect on the postoperative quality of life of the patient. More specifically, the postoperative rates of urogenital and sexual dysfunction that have been reported in the various series, are estimated at the levels of 70% and 90%, respectively. Additionally, TME is associated with the development of the low anterior syndrome (LARS). LARS is characterized by the onset of fecal incontinence, due to injury in the autonomic nerve plexuses that innervate the internal anal sphincter (IAS); who in turn is responsible for the 52-85% anal resting tone. According to a recent study, 38.8% and 33.7% of patients with normal preoperative urogenital function, developed postoperative stool and urine incontinence, respectively.

It becomes apparent that the incidence rates of these complications vary between the various series, mainly due to their small sample size, the lack of comparative data, the short follow up period, the use of non-validated tools and their retrospective design. Several predictive factors of these adverse events have been suggested in the literature, including old age, tumors located less than 12 cm from the anal verge, preoperative radiotherapy and injury to the pelvic autonomous nerves.

The clinical and functional anatomy of the pelvis are quite complex. The inferior hypogastric plexus is formed by the parasympathetic pelvic nerves, deriving from the I2-I4 and the sympathetic hypogastric nerve. It is a neural anatomic structure that carries organ-specific nerve fibers. Visual identification of the plexus is quite difficult, for various reasons, including the complexity of the nerve distribution, the narrow pelvis, the voluminous mesorectum, obesity, previous pelvic operations, neoadjuvant radiotherapy, locally advanced tumors, intraoperative bleeding and the extensive use of diathermy. According to the current literature, identification of the autonomous pelvic plexus is achievable in 72% of cases, whereas partial localization is possible only in 10.7% of patients.

Theoretically, intraoperative neuromonitoring of the pelvic autonomous nerves (pIONM), could quantify intraoperative nerve injuries, while in parallel, contribute to the improvement of the patients' postoperative quality of life. Several pIONM techniques have been described, including intra-urethral and intra-vesical pressure measurements. However, it was found that intermittent neuromonitoring objectifies the macroscopic integrity assessment of the sacral plexus. Recently, a promising technique, based on the simultaneous electromyography of the IAS and bladder manometry was developed, with encouraging results. During pIONM, the surgeon delivers electric stimuli to the autonomic nerve structures through a hand-held stimulator. At the same time, electromyogram changes of the IAS and the external anal sphincter (EAS), alongside intravesical pressure gradients are assessed.

Intraoperative neuromonitoring has been evaluated in several experimental studies. In a recent study, intraoperative simulation of the inferior hypogastric plexus with a bipolar stimulator resulted to the appearance of a measurable and repeatable electromyographic signal from the IAS.

Simultaneous signal processing from the IAS and urinary bladder, improves the, overall, diagnostic accuracy of these techniques. Stabilization of the electrodes outside the surgical field, has been, also, suggested by some researchers. Additionally, experimental studies evaluated the role of pIONM in the minimal invasive TME.

Moreover, the effectiveness of this technique has been a research subject in multiple clinical trials. In another study, where 85 patients underwent TME, after logistic regression, no use of pIONM and neoadjuvant radiotherapy, were identified as independent prognostic factors of postoperative urogenital deficit. Furthermore, the use of pIONM, was associated with a 100% sensitivity and a 96% specificity for the postoperative development of urogenital and anorectal functional complications.

The application of pIONM has been also suggested in the laparoscopic and robotic TME, using specially designed stimulators. In another trial, preservation of the plexus was achieved in 51.7% of patients submitted to a laparoscopic low anterior resection for rectal cancer. During one year follow-up, patients receiving pIONM, displayed a superiority in terms of postoperative urogenital function, as assessed by the IIEF, IPSS and FSFI questionnaires.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 44
• Est. completion date: September 19, 2027
• Est. primary completion date: September 19, 2026
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 90 Years

Eligibility

Inclusion Criteria:

• Histologically confirmed rectal cancer

• Surgical resection with TME

• <90 years old

• Signed informed consent

Exclusion Criteria:

• Emergency operation

• Presence of pacemaker

• Partial mesorectal excision

• Sepsis or systematic infection

• Physical or mental impairment

• Pregnancy or nursing

• Insufficient preoperative data for the urogenital/ anorectal function

• Lack of compliance with the research process

Related Conditions & MeSH terms

• Rectal Neoplasms

Intervention

Other:
• Pelvic Intraoperative Neuromonitoring
Pelvic Intraoperative Neuromonitoring (pIONM) allows mapping of the pelvic autonomous plexus during total mesorectal excision (TME).

Locations

Country	Name	City	State
Greece	University Hospital of Larissa	Larissa

Sponsors (3)

Lead Sponsor	Collaborator
Larissa University Hospital	General Hospital of Larissa, University of Thessaly

Country where clinical trial is conducted

Greece, 

References & Publications (33)

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* Note: There are 33 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in the quality of life of the patient at 3 months postoperatively, based on the SF-36 questionnaire	Change in the quality of life of the patient, at 3 months postoperatively, compared to the respective preoperative measurements, based on the Short Form 36 (SF-36) questionnaire SF-36: Short Form Survey Minimum Value: 0 Maximum Value: 100 Higher scores indicate a better outcome	Preoperatively, 3 months postoperatively
Secondary	Operative time	The total operative time will be recorded. Measurement unit: minutes	Intraoperative period
Secondary	Intraoperative bleeding	The total intraoperative blood loss volume will be recorded. Measurement unit: mL	Intraoperative period
Secondary	Postoperative discharge time	Postoperative time that the patient can be safely discharged. Measurement unit: hours. The patient will be discharged, when it is ensured that is medically safe to be released. In particular, as the exit time of the patient, will be regarded the time that the patient will fulfil the Clinical Discharge Criteria. More specifically, the patient should meet the following : steady vital signs, be oriented, without nausea or vomiting, mobilized with a steady gait, without a significant bleeding	Maximum time frame 15 days postoperatively
Secondary	Postoperative complications	Occurrence of postoperative complications (based on Clavien-Dindo classification). If such an episode occurs, then it will be defined as=1 'YES' If such an episode does not occur, then it will be defined as=0 'NO'	1 month postoperatively
Secondary	Negative resection margin	Occurrence of negative resection margin. If such an episode occurs, then it will be defined as=1 'YES' If such an episode does not occur, then it will be defined as=0 'NO'	1 month postoperatively
Secondary	Local recurrence	Occurrence of local recurrence. If such an episode occurs, then it will be defined as=1 'YES' If such an episode does not occur, then it will be defined as=0 'NO'	1 year postoperatively
Secondary	Bladder capacity	Urodynamic assessment. Evaluation of bladder capacity. Measurement unit: ml	Preoperatively and 2 months postoperatively
Secondary	Bladder compliance	Urodynamic assessment. Evaluation of bladder compliance. Measurement unit: ml/cm H2O	Preoperatively and 2 months postoperatively
Secondary	Detrusor pressure at maximum flow	Urodynamic assessment. Evaluation of detrusor pressure at maximum flow. Measurement unit: cm H2O	Preoperatively and 2 months postoperatively
Secondary	Maximum urinary flow rate	Urodynamic assessment. Evaluation of maximum urinary flow rate. Measurement unit: ml/s	Preoperatively and 2 months postoperatively
Secondary	Voiding volume	Urodynamic assessment. Evaluation of voiding volume. Measurement unit: ml	Preoperatively and 2 months postoperatively
Secondary	Post-void residual	Urodynamic assessment. Evaluation of post-void residual. Measurement unit: ml	Preoperatively and 2 months postoperatively
Secondary	Anal canal resting phase pressure	High-resolution Anorectal Manometry assessment. Evaluation of anal canal resting phase pressure. Measurement unit: mmHg	Preoperatively and 2 months postoperatively
Secondary	Sphincter zone length	High-resolution Anorectal Manometry assessment. Evaluation of sphincter zone length. Measurement unit: cm	Preoperatively and 2 months postoperatively
Secondary	Short squeeze test	High-resolution Anorectal Manometry assessment. Evaluation of short squeeze (5sec) pressure. Measurement unit: mmHg	Preoperatively and 2 months postoperatively
Secondary	Long squeeze test	High-resolution Anorectal Manometry assessment. Evaluation of long squeeze (30sec) pressure. Measurement unit: mmHg	Preoperatively and 2 months postoperatively
Secondary	Cough test	High-resolution Anorectal Manometry assessment. Evaluation of cough test (0 and 50 ml). If such an episode occurs, then it will be defined as=1 'YES' If such an episode does not occur, then it will be defined as=0 'NO'	Preoperatively and 2 months postoperatively
Secondary	Push test	High-resolution Anorectal Manometry assessment. Evaluation of push test (0 and 50 ml). If such an episode occurs, then it will be defined as=1 'YES' If such an episode does not occur, then it will be defined as=0 'NO'	Preoperatively and 2 months postoperatively
Secondary	RAIR test	High-resolution Anorectal Manometry assessment. Evaluation of rectoanal inhibitory reflex (RAIR) test (20 and 50 ml). If such an episode occurs, then it will be defined as=1 'YES' If such an episode does not occur, then it will be defined as=0 'NO'	Preoperatively and 2 months postoperatively
Secondary	Difference in the quality of life of the patient, based on the SF-36 questionnaire	Difference in the quality of life of the patient, at 6, 12, 24 months postoperatively, compared to the respective preoperative measurements, based on the Short Form 36 (SF-36) questionnaire SF-36: Short Form Survey Minimum Value: 0 Maximum Value: 100 Higher scores indicate a better outcome	Preoperatively, 6, 12, 24 months postoperatively
Secondary	Difference in the erectile function of the patient, based on the IIEF questionnaire	Difference in the erectile function of the patient, at 3, 6, 12, 24 months postoperatively, compared to the respective preoperative measurements, based on the International Index of Erectile Function (IIEF) questionnaire IIEF: International Index of Erectile Function Minimum Value: 0 Maximum Value: 5 Higher scores indicate a better outcome	Preoperatively, 3, 6, 12, 24 months postoperatively
Secondary	Difference in the sexual function of the patient, based on the FSFI questionnaire	Difference in the sexual function of the patient, at 3, 6, 12, 24 months postoperatively, compared to the respective preoperative measurements, based on the Female Sexual Function Index (FSFI) questionnaire FSFI: Female Sexual Function Index Minimum Value: 2 Maximum Value: 36 Higher scores indicate a better outcome	Preoperatively, 3, 6, 12, 24 months postoperatively
Secondary	Difference in the prostate symptoms of the patient, based on the IPSS questionnaire	Difference in the prostate symptoms of the patient, at 3, 6, 12, 24 months postoperatively, compared to the respective preoperative measurements, based on the International Prostate Symptom Score (IPSS) questionnaire IPSS: International Prostate Symptom Score Minimum Value: 0 Maximum Value: 35 Higher scores indicate a worse outcome	Preoperatively, 3, 6, 12, 24 months postoperatively
Secondary	Difference in the low anterior syndrome symptoms of the patient, based on the LARS questionnaire	Difference in the low anterior syndrome symptoms of the patient, at 3, 6, 12, 24 months postoperatively, compared to the respective preoperative measurements, based on the Low Anterior Resection Syndrome (LARS) questionnaire LARS: Low Anterior Resection Syndrome Minimum Value: 0 Maximum Value: 42 Higher scores indicate a worse outcome	Preoperatively, 3, 6, 12, 24 months postoperatively