Recommendations for evaluation of bladder and bowel function in pre-clinical spinal cord injury research

Abstract

Objective: In order to encourage the inclusion of bladder and bowel outcome measures in preclinical spinal cord injury (SCI) research, this paper identifies and categorizes 1) fundamental, 2) recommended, 3) supplemental and 4) exploratory sets of outcome measures for pre-clinical assessment of bladder and bowel function with broad applicability to animal models of SCI.

Methods: Drawing upon the collective research experience of autonomic physiologists and informed in consultation with clinical experts, a critical assessment of currently available bladder and bowel outcome measures (histological, biochemical, in vivo functional, ex vivo physiological and electrophysiological tests) was made to identify the strengths, deficiencies and ease of inclusion for future studies of experimental SCI.

Results: Based upon pre-established criteria generated by the Neurogenic Bladder and Bowel Working Group that included history of use in experimental settings, citations in the literature by multiple independent groups, ease of general use, reproducibility and sensitivity to change, three fundamental measures each for bladder and bowel assessments were identified. Briefly defined, these assessments centered upon tissue morphology, voiding efficiency/volume and smooth muscle-mediated pressure studies. Additional assessment measures were categorized as recommended, supplemental or exploratory based upon the balance between technical requirements and potential mechanistic insights to be gained by the study.

Conclusion: Several fundamental assessments share reasonable levels of technical and material investment, including some that could assess bladder and bowel function non-invasively and simultaneously. Such measures used more inclusively across SCI studies would advance progress in this high priority area. When complemented with a few additional investigator-selected study-relevant supplemental measures, they are highly recommended for research programs investigating the efficacy of therapeutic interventions in preclinical animal models of SCI that have a bladder and/or bowel focus.

Keywords:

• Spinal cord injury
• Animal models
• Outcome measures
• Functional assessment
• Bowel
• Colon
• Bladder
• Preclinical studies

Acknowledgements

The authors wish to acknowledge support received by the Craig H. Neilsen Foundation for the initial 2017 Bladder and Bowel Workshop that promoted the formation of the functional assessment working group. The authors further acknowledge the American Spinal Injury Association (ASIA) for hosting a luncheon for participants to discuss preliminary findings, during its 2018 annual meeting.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Andrei Krassioukov http://orcid.org/0000-0002-0022-7972

Additional information

Funding

This research received no specific funding agency support in the public, commercial, or not-for-profit sectors.