Relationship between gut-specific autonomic testing and bowel dysfunction in spinal cord injury patients

Abstract

Study design: Investigation of bowel function in 55 patients and 26 healthy volunteers using radiological, anorectal physiological and laser Doppler blood flow monitoring. Objectives: Bowel dysfunction is common after spinal cord injury (SCI). We aimed to determine whether hindgut testing of autonomic innervation provides insight into presence of symptoms, altered motor function (transit) and level of injury. Setting: St Mark's Hospital, UK and The Spinal Injuries Unit, Royal National Orthopaedic Hospital, UK. Methods: A total of 55 patients with chronic complete SCI and 26 healthy volunteers were studied. Twenty-four patients had lesions above T5 and 31 had lesions below T5. Thirty-five patients complained of constipation: 75% (18/24) of patients with lesions above T5 and 55% (17/31) of those with lesions below T5. Gut transit, rectal electrosensitivity and rectal blood flow were measured. Results: Slow gut transit occurred in 65% of patients and in all the 35 patients complaining of constipation. Delay was pancolonic. All patients had an elevated sensory threshold. The threshold was significantly higher in those with subjective constipation (Po0.01), slow transit (Po0.04) and high SCI (P ¼ 0.046). Mucosal blood flow was lower in SCI patients with constipation (Po0.04) and slow transit (Po0.03). It was higher than normal in high-SCI volunteers (P ¼ 0.056), reflecting loss of sympathetic inhibition. Conclusions: In SCI, subjective constipation correlates closely with slow gut transit. Delay is pancolonic, regardless of the site of lesion. Sensory testing provides evidence for completeness of lesion, offering further evidence for pain transmission through sympathetic pathways. Studies in SCI patients provide further evidence of mucosal blood flow as a marker of altered autonomic innervation.

Contrasting effects of cord injury on intravenous and oral pharmacokinetics of diclofenac: a drug with intermediate hepatic extraction

“…Hence, it appears that hemodynamic status has a major role in drug bioavailability changes observed after SCI. On the other hand, there is also evidence that SCI diminishes gastrointestinal motility, 4,19,20 leading to a slow gastric emptying that has been suggested to result in a reduced drug absorption at the duodenum. 4,[7][8][9][10]12 It is notable that the effect of SCI on absorption is of such magnitude that it not only compensates for reduced clearance, but also overrides it.…”

“…As mentioned above, SCI induces hemodynamic changes yielding a redistribution of tissue blood flow to ensure function of main organs such as the brain. 3 There is evidence that such redistribution can cause mucous gastrointestinal irrigation to be diminished, 19 and thereby contribute to decreased diclofenac absorption. Consistently, Medeiros et al 12 have described that SCI impairs the transport function of the intestinal mucosa and have suggested an association with blood pooling in the lower extremities and visceral organs, occurring during spinal shock that can alter abdominal Starling forces.…”

Transanal irrigation in myelomeningocele children: an alternative, safe and valid approach for neurogenic constipation

“…[15][16] Additional factors leading to bowel dysfunction in children with MMC are: a general decrease in activity, level lesion that causes abdominal muscle dysfunction, resulting in a decreased ability to push out stool. 17 An addition factor for incontinence is that children using wheelchairs or braces require more time to remove their clothing and go to the toilet. For these reasons, most infants and toddlers with MMC develop constipation, typically passing frequent, small and hard stools.…”

Multiple Sclerosis Related Bowel Dysfunction: Pathophysiology, Clinical Manifestation and Management

“…These sacral afferent fibres then travel via the spinothalamic tract and other ascending pathways to higher centres. Parasympathetic stimulation accelerates bowel transit whilst sympathetic stimulation slows down bowel transit [20][21][22]. Autonomic innervation can also alter internal anal sphincter function and rectal compliance [23].…”