When voluntary control of the anal sphincter
muscle is absent (most often due to spinal cord injury or
disease), "Digital Stimulation" is a technique often
employed by a caregiver to induce relaxation of the sphincter and
contraction of the colon, permitting scheduled
evacuation of the bowel. There are basically two methods of
performing this technique, ‘standard’ and ‘scissor’ methods.
In the standard technique, the index finger
is gloved, lubricated with water soluble lubricant jelly and
gently inserted into the anal canal. The finger is then rotated
against the sphincter wall. Imagine the sphincter as a circular
band of putty, the center of which you are trying to enlarge.
Relaxation of the sphincter generally takes between about 30
seconds and 2 minutes. As the sphincter loosens, the finger is
removed. If evacuation of stool does not occur, the procedure is
In the "Scissor Method", the gloved
and lubricated index and middle fingers are gently inserted into
the anal canal far enough to have the distal half of the fingers
in contact with the anal sphincter. A scissoring motion of the
fingers is used to "stretch" the sphincter open. Again,
relaxation typically occurs within 30 seconds to 2 minutes. As
the sphincter loosens, the fingers are removed.
is occasionally induced by digital stimulation. The risk of this
uncomfortable and sometimes dangerous problem can be minimized by
slower, gentler movements by the attendant during the stimulation
maneuvers, use of Nupercainal (Dibucaine by CIBA) 1%
rectal/topical ointment applied about 10 minutes before the
procedure, or by use of Xylocaine Lubricant Jelly (also applied
shortly before the procedure). The down side of using anesthetic
ointment/lubricant is possible failure of the technique to lead
to the desired enhanced colonic motility needed for evacuation.