Topical anesthesia blunts the pressor response induced by bowel manipulation in subjects with cervical spinal cord injury

Abstract

Prospective double-blind study. Manual emptying of rectal contents is necessary for patients with spinal cord injury to prevent bowel obstruction; however, this maneuver induces a rise in blood pressure (BP) and autonomic dysreflexia (AD). The purpose of this prospective double-blind study was to investigate whether topical anorectal anesthesia attenuates the BP rise and AD during bowel manipulation in patients with cervical spinal cord injury (CSCI). Kibikogen Rehabilitation Center for Employment Injuries. The study subjects were 25 consecutive clinically stable patients with CSCI. Each subject received a complete bowel program involving manual removal of stool in lateral recumbency, after topical application of lidocaine or placebo jelly to the anorectal area. Systolic and diastolic BP, heart rate and symptoms of AD were recorded before, during and after bowel manipulation. Systolic BP was significantly lower during the lidocaine arm of the study compared with placebo at insertion of rectal medication, digital stimulation, beginning of stool flow, manual removal of stool, end of stool flow and at 5-min after emptying. The mean maximal increase in systolic BP during lidocaine treatment (33.2+/-14.6 mm Hg) was less than during placebo (50.2+/-19.5 mm Hg, P<0.001). On the basis of our findings, we recommend induction of lidocaine jelly immediately before rectal manipulation in patients with CSCI to minimize the incidence and severity of AD.