Fecal Incontinence: A Simple Pneumatic Device for Home Biofeedback Training By C. G. Constantinides and S. Cywes
Cape Town, South Africa 9 A simple pneumatic biofeedback device has been designed for patients who have failed to develop social fecal continence following sacroabdominoperineal pull-through operations for anorectal anomalies, The components that make up the device are easily and cheaply available. This device was designed to be used by the patient at home and needs only the assistance of an adult. INDEX WORDS: Fecal incontinence; biofeedback.
E C O G N I T I O N of the role played by the
R puborectalis sling in the fecal continence mechanism, which in turn led to the operations that make a point of identifying, isolating, and utilizing this muscle in patients with anorectal anomalies, has been the most significant advance made toward achieving maximum expected defecatory control. Unfortunately, many patients fail to develop this "social" continence because they do not spontaneously and instinctively know how to effectively manipulate their puborectalis and other pelvic floor muscles. Biofeedback training (which in this situation may be defined as visual demonstration or representation of the effect of a voluntary action--in fact a type of introspection) was introduced to teach these patients how to effectively contract, and generally use to maximum advantage, the pelvic floor muscles. ~'2 The nerve supply to the pelvic floor in these patients must be normal. There seems to be no controversy regarding the effectiveness of biofeedback training, but the devices used to date have been cumbersome and employ sophisticated apparatus, necessitating the attendance of trained personnel and hospital visits. However, a simple, compact, and inexpensive device that can be used at home with minimal assistance from an adult has been designed. From the Department of Paediatric Surgery, Institute of Child Health, University of Cape Town and Red Cross War Memorial Children's Hospital, Cape Town, South Africa. Address reprint requests to Prof. S. Cywes, Department of Paediatric Surgery, Institute of Child Health, University of Cape Town, Cape Town, South Africa. 9 1983 by Grune & Stratton, Inc. 0022-3468/83/1803~9012501.00/0
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THE DEVICE
The new device consists of a probe made of flexible plastic tubing (approximately 1 cm in diameter) sealed off at one end with a streamlined plug (to facilitate insertion). Two ports (approximately 0.3 cm in diameter) are drilled in the side of the probe about 3.5 cm proximal to the tip. The part of the probe corresponding to the ports is covered by a sleeve of snugly fitting latex tubing. This sleeve is secured in place by means of ties, creating an airtight inflatable chamber. A French gauge 6 to 8 feeding tube is introduced proximally into the side of the probe and brought out through the "nose" of the plug, so that it protrudes about 2.5 cm. Both entry and exit sites are made airtight using a suitable adhesive. A 50-ml syringe with a three-way stopcock is connected to the proximal end of the feeding tube while a finger cot (which will act as a balloon) is fitted to the distal end (Fig. 1). The rest of the device consists of a blood pressure manometer pumping bulb and meter, lengths of flexible tubing, and a " Y " connector. Figure 2 illustrates the assembled device. USE OF THE DEVICE
The distance from the anal orifice to the puborectalis sling is determined by digital rectal examination. Measuring from the midpoint of the ports and going proximally, a ring mark is made on the probe at the point corresponding to the puborectalis: the anal orifice distance. The probe-is introduced until the ring mark reaches the anal orifice and is secured in that position with elastoplast. The chamber is then inflated just enough to make it bulge. In practice, we found that with the probe in situ adequate inflation corresponds to about 200 mm Hg. This will vary, of course, depending on anatomical parameters and the compliance of the latex chamber and the rest of the circuit. In the initial stages, the chamber may have to be inflated a bit more in order to dilate the puborectalis and, thus, will initiate a sensation that will be appreciated by the patient. This, in
Journal of Pediatric Surgery, Vol. 18, No. 3 (June), 1983
BIOFEEDBACK TRAINING FOR FECAL INCONTINENCE
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Feeding tube ( FG 6 - 8 ) Latex tubing "sleeve"
/
Finger cot ( balloon )
1 cm
o
2,5 cm
, 1, 5 cm I
!
\ Flexible plastic tube
3,5 cm Fig. 1.
Fig. 2.
Details of design and dimensions of the probe (not drawn to scale).
turn, will make it easier for him or her to realize which muscles to contract. The balloon is momentarily inflated with the minimum volume of air necessary to give the patient a sensation reminiscent of the arrival of a stool bolus. The patient is then encouraged to contract the puborectalis in response to this sensation. The patient holds and looks at the meter. If he or she "squeezes" appropriately, there will be a clockwise deflection of the needle. The balloon is then deflated and the procedure repeated. No notice need be paid to the readings, although later the patient should be encouraged to try and increase the arc of deflation (a rough indicator of the force of contraction). It is envisaged that with regular exercise, the puborectalis will hypertrophy and, thus, contract more forcefully with less conscious effort.
The assembled biofeedback device.
REFERENCES
1. Engel BT, Nikoomanesh P, Schuster MM: Operant conditioningof rectosphincteric responses in the treatment of fecal incontinence. N Engl J Med 290:646-649, 1974
2. Olness K, McParland FA, Piper J: Biofeedback:A new modality in the management of children with fecal soiling. J Pediatr 96:505-509, 1980