The colonic J-pouch in colo-anal anastomosis.

Anastomosis of the colon to the anal canal is now an accepted technique in the surgical management of low and mid rectal cancers. Although significant postoperative bowel disturbance is often seen with straight colo-anal anastomosis, controversy exists over the benefit of adding a colonic pouch for low anastomoses. Several short and long-term studies have demonstrated the early functional superiority of pouch-anal over straight anastomosis. Pouch construction does not compromise anal physiological parameters. It is recommended the pouch be constructed from a length of descending colon and be small (5 cm) in size to adequately act as a neo-rectum; long-term evacuatory difficulties are encountered with the construction of large pouches (10 cm). Anastomotic complications appear to be less frequent with pouch surgery; construction of a pouch does not significantly add to operative time, patient morbidity and mortality. At present there is no compromise to long-term oncological survival. The data supporting these statements is weak and based largely upon retrospective studies. Furthermore the impact of improved function with pouch-anal anastomosis on overall quality of life has been poorly investigated. Further prospective randomized studies are required to ascertain whether the potential benefits of a colonic pouch are realized in the randomized setting.

A double-blind randomized placebo-controlled trial of oral indoramin to treat chronic anal fissure.

BACKGROUND: Indoramin is an alpha1-adrenoceptor antagonist and has been shown to reduce anal resting pressure. Its therapeutic potential has not been explored. The aim of this study was to determine the outcome of treatment with oral indoramin on patients with chronic anal fissure in the setting of a double-blind randomized placebo-controlled trial. METHODS: Twenty-three patients with chronic anal fissure were computer randomized to receive a 6-week course of oral indoramin (20 mg) or placebo in identical capsules, twice daily and with bulk-forming laxatives. Pain was assessed by a visual analogue scale from 0 to 10. Anal resting pressure, heart rate and blood pressure were recorded. Patients were reviewed 1 h after taking the capsule and at 2, 6 and 12 weeks thereafter. RESULTS: Fourteen patients were randomized to indoramin and 9 to placebo. Maximum anal resting pressure was reduced from a mean of 96.4 cm H2O (+/- 32) to 67.6 cm H2O (+/- 26), 1 h after indoramin (P=0.02) and there was no significant change after placebo. There were no significant changes in heart rate or blood pressure. Pain was reduced in the placebo group from a score of 4.9 to 2.0 after 6 weeks (P < 0.01) but not in the indoramin group. After 6 weeks, healing had occurred in one (7%) patient in the indoramin group and in 2 (22%) in the placebo group (P > 0.1). After 3 months, the chronic anal fissure in the indoramin group had recurred. The trial was terminated early because of poor healing rates. CONCLUSION: An oral dose of indoramin (20 mg) administered twice daily reduced anal resting pressure by 30% compared with pretreatment levels but was ineffective in healing chronic anal fissures.

Evidence from dynamic integrated proctography to redefine anismus.

The role of anismus in the aetiology of defective rectal evacuation was investigated by dynamic integrated proctography in 20 controls and 71 constipated patients. Normal parameters were defined and compared between 21 constipated patients with poor evacuation during proctography (< 40 per cent of contrast evacuated; group 1) and 50 who evacuated fully (> 90 per cent of contrast evacuated; group 2). Nine patients in group 1 failed to evacuate. Radiological abnormalities of the rectum were recorded in all groups but obstructed evacuation was not observed. Anismus (defined as a recruitment of puborectalis electromyogram (EMG) activity of > 50 per cent) was significantly more common in group 1 than group 2 patients (14 of 21 versus 12 of 50, P < 0.01) and present in seven of those unable to evacuate. Eight patients in group 1 failed to raise intrarectal pressure > 50 cmH2O compared with two in group 2 (P < 0.001). Six patients in group 1 demonstrated both anismus and inability to raise intrarectal pressure, which may combine to cause defective evacuation. EMG recruitment alone is insufficient to diagnose anismus. Definition should be based on three criteria: demonstration of puborectalis EMG recruitment of > 50 per cent; evidence of an adequate level of intrarectal pressure (> 50 cmH2O) on straining; and presence of defective evacuation.

Development of an electrically stimulated neoanal sphincter.

In early surgical attempts to create a neoanal sphincter for patients who are faecally incontinent, skeletal muscle (usually the gracilis) has been transposed around the anal canal. Despite modifications, such as intermittent electrical stimulation, this procedure is likely to fail because the fast-twitch gracilis muscle is incapable of prolonged contraction without fatigue. Long-term electrical stimulation to convert such a muscle to a slow-twitch, fatigue-resistant muscle, though practicable, has yielded inconsistent results. We describe further modifications of this technique. A neoanal sphincter was constructed with an electrically stimulated transposed gracilis muscle in 20 incontinent patients with a deficient anal sphincter, and as part of a reconstruction in 12 patients in whom the anorectum had been excised or was congenitally absent. A totally implanted stimulator was used to convert the muscle from a fast-twitch to a slow-twitch muscle. Other modifications included vascular delay 4-6 weeks before transposition of the muscle, stimulation of the main nerve to the gracilis rather than its peripheral branches, and intermittent higher frequency stimulation. 2-4 of these modifications gave significantly fewer failures than did 0-1. With the new technique, continence has been restored in patients whose only other treatment option was a permanent stoma.

Evidence for motor neuropathy and reduced filling of the rectum in chronic intractable constipation.

Subtotal colectomy with ileorectal anastomosis is now frequently offered to patients with slow transit constipation who have severe symptoms and no response to more conventional medical treatment. If this operation is to be successful, the underlying problem should be delay in the progress of contents through the colon but no mechanical or functional obstruction in the small bowel or rectum. We have used a recently described technique of prolonged ambulant manometry and electromyography to investigate anorectal function in these patients. Pressure data were collected using a 2 mm diameter intrarectal probe carrying microtransducers, and external anal sphincter activity was assessed by a pair of silver-silver chloride surface electrodes. Fourteen control subjects and eight patients with colonic inertia were studied. Sampling reflexes, indicative of rectal filling, occurred at mean (SEM) rates of 7.4 (2.0)/hour in controls but were significantly reduced in patients (2.4 (0.3)/hour (p less than 0.01]. Recurrent rectal motor complexes were seen to occur in both groups at intervals of 76 (1.8) minutes in controls and 64.9 (7.2) minutes in patients (p less than 0.1), and with amplitudes of 42.4 (2.1) mmHg and 9.2 (0.7) mmHg (p less than 0.001), respectively. External sphincter electromyographic spike activity did not differ between groups. Our results support the concept of reduced transit of faeces to the rectum from the colon over a 24 hour period in slow transit constipation and suggest that a motor neuropathy may also be present in the rectum.

Restoration of gastrointestinal continuity and continence after abdominoperineal excision of the rectum using an electrically stimulated neoanal sphincter.

A new operation is described in which a neorectum and neoanal sphincter mechanism have been constructed to restore gastrointestinal continuity and continence in a patient who required abdominoperineal excision of the rectum for a low rectal cancer. The neorectum was constructed by bringing colon down into the pelvis and anastomosing it to the perineal skin. The neoanal sphincter was fashioned from a transposed gracilis muscle and was activated electrically by a totally implanted stimulator. A period of chronic low-frequency stimulation altered the muscle characteristics and enabled the neosphincter to contract continually without fatigue. The patient was continent when the stimulator was turned on and was able to void when the stimulator was turned off.

Construction of a neoanal sphincter by transposition of the gracilis muscle and prolonged neuromuscular stimulation for the treatment of faecal incontinence.

Six patients incapacitating faecal incontinence, in whom conventional treatment had either failed or was contraindicated, were treated by a new technique. A neonanal sphincter was constructed by transposing the gracilis muscle around the anal canal. Chronic neuromuscular stimulation via an implanted electrical stimulator was then used in an attempt to convert the muscle to a slow twitch fatigue resistant muscle. Physiological measurements suggested that this conversion had begun, enabling the neosphincter to mount a sustained contraction. Five patients had their covering stomas closed, and continence was improved in all of them. However, one patient could not cope psychologically with the stimulator, and another patient was continent for long periods only when the neosphincter was used in conjunction with a silastic plug. This new technique may benefit selected patients with incontinence whose only alternative would be a permanent stoma.

Electrically stimulated sartorius neosphincter: canine model of activation and skeletal muscle transformation.

The sartorius muscle was transposed into the abdominal cavity of six dogs, passed around a Thiry-Vella loop and sutured to itself to form a neosphincter. The muscle was activated by electrical stimulation and on contraction the neosphincter stopped or reduced the flow of saline through the Thiry-Vella loop in all animals until the onset of muscle fatigue. Continuous low frequency stimulation was used to transform the skeletal muscle, and when studied after a mean of 8 weeks of stimulation (range 6-11 weeks) the neosphincter stopped the flow for a significantly longer period of time (P = 0.027). Associated with the improved neosphincter function was a significant decrease in the fusion frequency (P = 0.003) and prolongation of the stimulus-peak tension time as assessed by a strain gauge sutured to the neosphincter muscle (P = 0.002). The changes in the contraction properties of the skeletal muscle suggest that continuous low frequency stimulation transformed the muscle fibres from type 2 to type 1, resulting in improved fatigue resistance and potential for continuous sphincter activity.

Function after ileal pouch and stapled pouch-anal anastomosis for ulcerative colitis.

Fourteen patients with ulcerative colitis underwent formation of an S ileal pouch and construction of a stapled pouch-anal anastomosis by a modified technique, which eliminated the use of purse-string sutures. Eleven have had their covering ileostomies closed. Anal manometry performed before and a median of 9 months after ileostomy closure showed significant impairment of internal anal sphincter function. Night evacuation was significantly reduced in the stapled group compared with a similar group of patients who had undergone S ileal pouch formation, mucosal proctectomy and manual transanal anastomosis, but this was the only parameter of function to show a difference. A stapled pouch-anal anastomosis may be superior to the conventional procedure but it still may lead to internal anal sphincter damage which cannot be due to mucosectomy or prolonged anal retraction.

Construction of a neorectum and neoanal sphincter following previous proctocolectomy.

A new operation is described in which a neorectum and neoanal sphincter mechanism have been constructed to restore gastrointestinal continuity and continence in a patient who had previously undergone proctocolectomy and a permanent ileostomy. The neorectum was constructed by forming a triplicated pouch from the distal ileum. The neoanal sphincter was fashioned from a transposed gracilis muscle and was activated electrically by an implanted stimulator. A period of chronic low frequency stimulation altered the muscle characteristics and enabled the neosphincter to contract continually without fatigue. Complete continence was achieved by the neosphincter gripping a Silastic plug inserted within the efferent spout of the pouch. The patient was able to void completely when the stimulator was switched off and the plug removed.

Prolonged ambulant assessment of anorectal function in patients with prolapsing hemorrhoids.

Six patients with prolapsing hemorrhoids and 12 control subjects had assessment of anorectal pressure and external sphincter electromyography performed over a prolonged period under ambulant conditions. Patients with prolapsing hemorrhoids demonstrated greater degrees of sampling responses, 12.9 +/- 1.9/hour, vs. 7.4 +/- 2.0/hour (mean +/- SEM) in controls (P less than .05). Ultraslow wave and giant ultraslow wave activity were seen frequently in the patient group occupying more than 30 percent of recording. The external sphincter demonstrated much greater electrical activity (spike potentials) in patients with hemorrhoids than in controls both by day, 24.9 +/- 11.0/10 min vs. 12.8 +/- 3.2/10 min (P less than .02), and by night, 7.4 +/- 2.6 min vs. 1.6 +/- 1.3/10 min (P less than .03). Sleep electrical activity in the presence of hemorrhoids did not differ significantly from that of controls during waking, 7.4 +/- 2.6/10 min vs. 12.8 +/- 3.2/10 min (P less than .1). No difference in phasic and periodic rectal motor activity was noted between patient and control groups. This demonstrates the application of prolonged assessment of anorectal motility and external sphincter activity in a patient group. Abnormalities previously documented in patients with hemorrhoids using conventional manometric tests were confirmed. In addition, evidence of increased external sphincter function during waking and sleep may have implications in the pathophysiology of this disorder.

Comparison of digital and manometric assessment of anal sphincter function.

Anal sphincter function was assessed by digital examination and anal canal manometry in 66 patients and controls. Digital scores were allotted by using visual analogue scales for basal and squeeze sphincter function and were compared with the corresponding pressures. There were good correlations between digital basal score and maximum basal pressure (Spearman rank correlation coefficient rs = 0.56, P less than 0.001), and digital squeeze score and maximum squeeze pressure (rs = 0.72, P less than 0.001). There were wide ranges of sphincter function on digital and manometric assessment with considerable overlap between patient groups. Digital scores detected differences in sphincter function between patient groups as accurately as manometry. The sensitivities and specificities of digital scores and anal canal manometry in segregating continent and incontinent patients were similar. It was concluded that digital estimation was equally as good as assessment of anal sphincter function as anal canal manometry.

Vasectomy: how much is enough?

Bilateral vasectomy was performed in 30 men. The vasa were tied with radio-opaque ligatures and X-rays taken to assess the separation of the ends. There was good correlation between the length of vas excised and the resulting separation of the markers. In order to achieve a separation greater than that of sperm granulomas associated with vasectomy failure, at least 7 cm of vas would have to be removed. However, excision of this length cannot be recommended because of subsequent difficulties with vasovasostomy. It is suggested that as well as excising a length of vas during vasectomy, a second method is also used to prevent spontaneous recanalisation.

PIP: The relationship between the length of vas excised and the separation of the ends was investigated in 30 men who underwent routine bilateral vasectomy under local anesthesia. The vas was isolated from its fascial sheath and a variable length was excised from both sides. The ends of the vasa were ligated with 3/0 braided steel sutures and allowed to slip back into their fascial coverings without additional measures to prevent recanalization. A median of 22.5 mm of vas (range, 3-72 mm) was excised from the 60 vasa. The median initial radiologic separation of the markers was 10.5 mm (range, 3-52 mm), with a final median separation of 7 mm (range, 2-50 mm). There was a positive correlation between the length of vas excised and both the immediate and final separations. In order to achieve a separation greater than that of sperm granulomas associated with vasectomy failure, at least 7 cm of vas should be removed. However, excision of this length would create serious difficulties in the event of subsequent vasovasectomy. So that only a short segment of vas needs to be excised, it is recommended that an additional procedure (e.g., diathermy fulguration of the lumen of the vas) be used in bilateral vasectomy to prevent spontaneous recanalization and yet make future sterilization reversal possible.

Treatment of anismus in intractable constipation with botulinum A toxin.

In seven patients with anismus the striated sphincter muscle complex was selectively weakened by local injection of Clostridium botulinum type A toxin. Symptom scores improved significantly and correlated with a significant reduction in the maximum voluntary and canal squeeze pressure and a significant increase in the anorectal angle on straining. Botulinum A toxin seems to be promising treatment for some patients with anismus.