Skip to main content
Top
Published in: BMC Urology 1/2020

01-12-2020 | Transurethral Prostate Resection | Technical advance

Risk assessment of neuromuscular stimulation by energy-based transurethral resection devices: an ex vivo test standard

Authors: Ulrich Biber, Ovidiu Jurjut, Markus D. Enderle, Wilhelm K. Aicher

Published in: BMC Urology | Issue 1/2020

Login to get access

Abstract

Background

During transurethral resection of bladder tumours (TURB), radio-frequency (RF) currents can lead to adverse neuromuscular stimulation (NMS). Here we present a novel ex vivo method to determine the risk of RF generators and their bipolar TURB modes to cause NMS. We aimed to develop an experimental platform for safety evaluation of new RF generators and their modes with a newly established test standard, suitable for replacement or reduction of animal testing.

Methods

We tested four contemporary RF generators with their bipolar modes for TURB in saline. A two-stage ex vivo approach was pursued: First, we recorded voltages at possible positions of the obturator nerve behind a porcine bladder wall in a TURB model using 18 RF applications per generator. Second, these voltage records were used as stimuli to evoke nerve compound action potentials (CAPs) in isolated porcine axillary nerves. The NMS potential was defined as the ratio between the observed area under the CAPs and the theoretical CAP area at maximum response and a firing rate of 250 Hz, which would reliably induce tetanic muscle responses in most human subjects. The measurement protocol was tailored to optimise reproducibility of the obtained NMS potentials and longevity of the nerve specimens.

Results

As prerequisite for the clinical translation of our results, the robustness of our test method and reproducibility of the NMS potential are demonstrated with an excellent correlation (r = 0.93) between two sets of identical stimuli (n = 72 each) obtained from 16 nerve segments with similar diameters (4.2 ± 0.37 mm) in the nerve model. The RF generators differed significantly (p < 0.0001) regarding NMS potential (medians: 0–3%).

Conclusions

Our test method is suitable for quantifying the NMS potential of different electrosurgical systems ex vivo with high selectivity at a reasonable degree of standardization and with justifiable effort. Our results suggest that the clinical incidence of NMS is considerably influenced by the type of RF generator. Future generations of RF generators take advantage from the proposed test standard through higher safety and less animal testing. Health professionals and treated patients will benefit most from improved RF surgery using generators with a low NMS risk.
Appendix
Available only for authorised users
Literature
1.
go back to reference Hug B, Haag R. Hochfrequenzchirurgie. In: Kramme R, editor. Medizintechnik: Verfahren, Systeme, Informationsverarbeitung; mit 170 Tabellen. 3rd ed. Heidelberg: Springer; 2007. p. 515–38.CrossRef Hug B, Haag R. Hochfrequenzchirurgie. In: Kramme R, editor. Medizintechnik: Verfahren, Systeme, Informationsverarbeitung; mit 170 Tabellen. 3rd ed. Heidelberg: Springer; 2007. p. 515–38.CrossRef
4.
go back to reference Prentiss RJ, Harvey GW, Bethard WF, Boatwright DE, Pennington RD. Massive adductor muscle contraction in transurethral surgery: cause and prevention; development of new electrical circuitry. Trans Am Assoc Genitourin Surg. 1964;56:64–72.PubMed Prentiss RJ, Harvey GW, Bethard WF, Boatwright DE, Pennington RD. Massive adductor muscle contraction in transurethral surgery: cause and prevention; development of new electrical circuitry. Trans Am Assoc Genitourin Surg. 1964;56:64–72.PubMed
6.
go back to reference Shulman MS, Vellayappan U, Monaghan TG, Coukos WJ, Krenis LJ. Simultaneous bilateral obturator nerve stimulation during transurethral electrovaporization of the prostate. J Clin Anesth. 1998;10:518–21.CrossRefPubMed Shulman MS, Vellayappan U, Monaghan TG, Coukos WJ, Krenis LJ. Simultaneous bilateral obturator nerve stimulation during transurethral electrovaporization of the prostate. J Clin Anesth. 1998;10:518–21.CrossRefPubMed
12.
go back to reference Atanassoff PG, Weiss BM, Brull SJ, Horst A, Külling D, Stein R, Theiler I. Electromyographic comparison of obturator nerve block to three-in-one block. Anesth Analg. 1995;81:529–33.PubMed Atanassoff PG, Weiss BM, Brull SJ, Horst A, Külling D, Stein R, Theiler I. Electromyographic comparison of obturator nerve block to three-in-one block. Anesth Analg. 1995;81:529–33.PubMed
13.
go back to reference Atanassoff PG, Weiss BM, Brull SJ, Horst A, Külling D, Stein R, Theiler I. Compound motor action potential recording distinguishes differential onset of motor block of the obturator nerve in response to etidocaine or bupivacaine. Anesth Analg. 1996;82:317–20.PubMed Atanassoff PG, Weiss BM, Brull SJ, Horst A, Külling D, Stein R, Theiler I. Compound motor action potential recording distinguishes differential onset of motor block of the obturator nerve in response to etidocaine or bupivacaine. Anesth Analg. 1996;82:317–20.PubMed
21.
go back to reference Lapicque L. Recherches quantitatives sur l'excitation électrique des nerfs traitée comme une polarization. J Physiol Pathol Gen. 1907;9:620–35. Lapicque L. Recherches quantitatives sur l'excitation électrique des nerfs traitée comme une polarization. J Physiol Pathol Gen. 1907;9:620–35.
27.
go back to reference Blinks JR, Rudel R, Taylor SR. Calcium transients in isolated amphibian skeletal muscle fibres: detection with aequorin. J Physiol. 1978;277:291–323.CrossRefPubMedPubMedCentral Blinks JR, Rudel R, Taylor SR. Calcium transients in isolated amphibian skeletal muscle fibres: detection with aequorin. J Physiol. 1978;277:291–323.CrossRefPubMedPubMedCentral
29.
go back to reference Schook LB, Tumbleson ME. Advances in swine in biomedical research. New York: Plenum Press; 1996. Schook LB, Tumbleson ME. Advances in swine in biomedical research. New York: Plenum Press; 1996.
33.
go back to reference Biró G. Excitatory effects of the electrical activity of muscle on the contiguous nerve. Acta Biochim Biophys Acad Sci Hung. 1977;12:403–10.PubMed Biró G. Excitatory effects of the electrical activity of muscle on the contiguous nerve. Acta Biochim Biophys Acad Sci Hung. 1977;12:403–10.PubMed
34.
go back to reference Maleque MA, Adhikary PK, Pavuluri S, Kopsombut P, Rucker HK. Potentiation of cholinergic activity with pyridino1,2-aimidazo5,4-bindole: in vitro studies. Gen Pharmacol. 1990;21:199–203.CrossRefPubMed Maleque MA, Adhikary PK, Pavuluri S, Kopsombut P, Rucker HK. Potentiation of cholinergic activity with pyridino1,2-aimidazo5,4-bindole: in vitro studies. Gen Pharmacol. 1990;21:199–203.CrossRefPubMed
Metadata
Title
Risk assessment of neuromuscular stimulation by energy-based transurethral resection devices: an ex vivo test standard
Authors
Ulrich Biber
Ovidiu Jurjut
Markus D. Enderle
Wilhelm K. Aicher
Publication date
01-12-2020
Publisher
BioMed Central
Published in
BMC Urology / Issue 1/2020
Electronic ISSN: 1471-2490
DOI
https://doi.org/10.1186/s12894-020-00630-5

Other articles of this Issue 1/2020

BMC Urology 1/2020 Go to the issue