Reduction In Anal Pressure Research Articles

Effectiveness of a high fiber diet in improving constipation in patients with defecatory dyssynergy under treatment with anorrectal biofeedback. Exploratory, randomized clinical trial

Introductionfiber is the initial treatment in chronic functional constipation. However, its role in the group of patients with defecatory dyssynergy is not well established. The objective of the study is to evaluate the efficacy and safety of a high fiber diet in patients with defecatory dyssynergy in the treatment with anorectal biofeedback. Patients and methodsAn exploratory, randomized (1:1), double-blind, controlled "add-on" clinical trial was carried out in a reference center in Spain in patients with functional constipation and defecatory dyssynergy according to the ROME IV criteria. Control group: treatment with biofeedback and low-fiber diet (15−20 g/day). Experimental group: treatment with biofeedback and high fiber diet (25−30 g/day). Analyzed: responder (primary endpoint), patient whose defecatory dyssynergy had been corrected (>20% reduction in anal pressure during the defecation maneuver and normal balloon expulsion test); anorectal parameters (anal relaxation, reduced straining); safety (abdominal symptoms: flatulence, pain, borborygmus, bloating). ResultsA total of 44 patients were randomized: 22 per group. The percentage of responders was 75% (15/20, 95% CI: 53 89%) control group and 70% (14/20, 95% CI: 48–85%) experimental group, p value: 0.225. Differences in favor of the control group were only observed in abdominal symptoms: flatulence (p-value: 0.028), abdominal distension (p-value: 0.041) and digestive comfort (p value: 0.043). ConclusionsIn patients with defecatory dyssynergy, a high-fiber diet not only does not improve the efficacy of anorectal biofeedback but is associated with a loss of improvement in abdominal symptoms.

Are There Sex Differences in Defecation Patterns in Patients with Defecation Disorders? - A Single-center Observational Study.

Defecation disorders (DD) are characterized by impaired rectal evacuation due to inadequate defecatory propulsion and/or dyssynergic defecation. DD are assessed by rectal and anal pressures during attempted defecation using anorectal manometry (ARM). Thus far, at least four types of dyssynergic patterns have been recognized on ARM. This study aimed to compare the manometric parameters and dyssynergic patterns between men and women with DD. This study enrolled consecutive patients undergoing anorectal tests for symptoms of DD. Anorectal pressure was measured using a waveform ARM system. DD were diagnosed based on the results of ARM, balloon expulsion tests, and barium defecography. Dyssynergic patterns were defined as a paradoxical increase in anal pressure with (type I) or without (type II) an adequate increase in rectal pressure and failure of a reduction in anal pressure with (type III) or without (type IV) an adequate increase in rectal pressure. This study evaluated 324 women and 234 men. Based on anorectal tests, 73.1% men and 54.6% women were diagnosed with DD. Rectal and anal pressures during attempted defecation in patients with DD were significantly higher in men than in women. Type I patterns were more common in men (64.9%) than in women (28.2%). Conversely, type II (42.9% vs. 24.0%) and IV (20.9% vs. 5.8%) patterns were observed more frequently in women than in men. Men were more likely to experience dyssynergic defecation whereas women were more likely to experience inadequate defecatory propulsion. However, future studies are warranted to confirm these results.

Eficacia de la dieta alta en fibra en la mejora del estreñimiento en pacientes con disinergia defecatoria en tratamiento con biofeedback anorrectal. Ensayo clínico exploratorio, aleatorizado

IntroductionFiber is the initial treatment in chronic functional constipation. However, its role in the group of patients with defecatory dyssynergy is not well established. The objective of the study is to evaluate the efficacy and safety of a high fiber diet in patients with defecatory dyssynergy in the treatment with anorectal biofeedback. Patients and methodsAn exploratory, randomized (1:1), double-blind, controlled «add-on» clinical trial was carried out in a reference center in Spain in patients with functional constipation and defecatory dyssynergy according to the ROMEIV criteria. Control group: treatment with biofeedback and low-fiber diet (15-20g/day). Experimental group: treatment with biofeedback and high fiber diet (25-30g/day). Analyzed: responder (primary endpoint), patient whose defecatory dyssynergy had been corrected (>20% reduction in anal pressure during the defecation maneuver and normal balloon expulsion test); anorectal parameters (anal relaxation, reduced straining); safety (abdominal symptoms: flatulence, pain, borborygmus, bloating). ResultsA total of 44 patients were randomized: 22 per group. The percentage of responders was 75% (15/20; 95%CI: 53 89%) control group and 70% (14/20; 95%CI: 48-85%) experimental group, P=.225. Differences in favor of the control group were only observed in abdominal symptoms: flatulence (P=.028), abdominal distension (P=.041) and digestive comfort (P=.043). ConclusionsIn patients with defecatory dyssynergy, a high-fiber diet not only does not improve the efficacy of anorectal biofeedback but is associated with a loss of improvement in abdominal symptoms.

High-resolution Anorectal Manometry Findings in Dyssynergic Defecation

Introduction: Dyssynergic defecation (DD) is the most common disorder of defecation and affects up to 40% of patients with chronic constipation. Four types of DD have been defined by anorectal manometry, these are characterized by a paradoxical increase in anal pressure with (type I) or without (type II) adequate increase in rectal pressure and failure of reduction in anal pressure with (type III) or without (type IV) adequate increase in rectal pressure. It is unknown whether there are any differences between manometric parameters in DD types and the frequency of DD in our population. Methods: Study of patients who underwent high-resolution anorectal manometry for functional constipation during January 2013 to July 2015 in a tertiary referral center. For statistical analysis, the frequencies were expressed as percentages and comparative statistics by Student's T-Test and Wilcoxon rank test were applied, and relationships between manometric findings were evaluated by calculation of Spearman's correlation coefficient. P values < 0.05 were considered significant. Results: DD was found in 58 subjects, of which 81% (N = 47) were women. The average age was 42.95 ± 19.52. In the population with DD there was a positive correlation between the intrarectal pressure (IRP) and the anal canal length (r = 0.405 p = 0.002), the first sensation and height (r = 0.406, p = 0.002), the anorectal differential pressure (ARDP) and the anal relaxation percentage (r = 0.560, p < 0.001), the IRP and maximum sphincter pressure at rest MaxSPR (r = 0.480, p < 0.001), and in the IRP and the ARDP (r = 0.567, p < 0.001). The most common type of DD was the type I in 58.6% (N = 34), followed by type III in 19% (N = 11), Type II in 17.2% (N = 10) and Type IV in 5.2% (N = 3). Significant differences in the anal residual pressure between the group I and IV DD (103.25±46 vs 45.40±34 mmHg p < 0.05, see FIGURE1) were found. We found differences in the first sensation between DD subtypes according to gender (p < 0.05, see FIGURE2).Figure 1Figure 2Conclusion: DD is more common in women and type I is the most common in our population. The anal residual pressure distinguishes between the type I and the type IV. There are gender variations in rectal sensitivity among the dyssynergic defecation subtypes. We assume that these differences may be related to visceral hypersensitivity. The categorization of the types of DD perhaps will allow us to provide prognostic information and guide the direction of treatment.

A 56-Year-Old Woman With Severe Chronic Constipation: What Is the Underlying Pathology?

A 56-year-old woman with chronic constipation visited Chung-Ang University Hospital. She had suffered from chronic constipation, abdominal pain and abdominal distention, and took prokinetics, bulking agents and osmotic laxatives for more than 5 years. Her symptoms became worse and she could defecate only 3 or 4 times per a month. She had no history of any specific medical disease or trauma. The abdomen was distended without palpable mass. The laboratory findings were not remarkable. The plain abdominal radiograph showed ileus with air-fluid levels (Fig. 1A). Abdominopelvic CT revealed a marked colonic distension, whereas the entire colon was well traced without a definite obstructive lesion (Fig. 1B). During the colonoscopy and double-contrast barium enema, there was neither an intra-luminal lesion nor narrowed segment which was suggestive of transitional zone. Colon transit time using radio-opaque markers was severely prolonged. The right, left, rectosigmoid and total colon transit time were 106.8, 21.6, 13.2 and 141.6 hours, respectively. Anorectal manometric findings were within normal range and the rectoanal inhibitory reflex was well preserved (Fig. 2). Figure 1 Abdominal X-ray and CT findings. (A) The plain abdominal radiograph shows ileus with multiple air-fluid levels. (B) Abdominopelvic CT reveals marked colonic distensions with abundant feces and fluid from cecum to sigmoid colon, whereas the entire colon ... Figure 2 Rectoanal inhibitory reflex on anorectal manometry. Rapid rectal distention with balloon (30 mL) induces a transient increase in rectal pressure, followed by a more prolonged reduction in anal pressure due to relaxation of the internal anal sphincter. ... She has taken large doses of laxatives for several months, and her symptoms improved temporally. However, the constipation aggravated again and her quality of life deteriorated progressively. Since escalation of medication had not been effective for her constipation for many years, surgical treatment was chosen under the impression of chronic intestinal pseudo-obstruction. Total colectomy with ileorectal anastomosis was performed. Histologically, markedly decreased number of ganglion cells in the myenteric plexus was observed in the entire colon (Fig. 3) in which the pathologic findings confirmed hypoganglionosis. Figure 3 Myenteric (Auerbach) plexus of the colon of the present case (A, B) and the control (C, D). (A) The number of ganglion cells in the present case is markedly reduced (arrow) compared to that in the control (H&E, ×200). (B) Serial section ... Chronic intestinal pseudo-obstruction is a rare debilitating disorder characterized by obstructive symptoms without any lesion occluding the gut.1,2 Chronic idiopathic intestinal pseudoobstruction (CIIPO) is diagnosed when the underlying cause is not found in spite of the thorough medical examination.3,4 The present case is a neuropathic type of CIIPO, and demonstrates hypoganglionosis to be involved in medically intractable chronic constipation.

Why the most potent toxin may heal anal fissure

An anal fissure is a painful linear ulcer in the lower part of the anal canal. It is very often referred to as an ischemic ulcer. Anodermal blood flow is negatively correlated with resting pressure of the anus. Increased activity of the internal anal sphincter may decrease the anodermal blood supply by compressing arterioles. Surgical procedures and botulinum treatment for patients with chronic anal fissure produce a temporary reduction in anal pressure, reverse sphincter spasm, and promote fissure healing. However, recent studies have shown that fissure healing does not appear to be dependent on reduction in mean resting anal pressure. On the basis of the published literature, this article attempts to explain this phenomenon in detail. The mechanism of action of botulinum toxin on the internal anal sphincter is not yet fully understood. This review focuses on problems associated with anal fissure treatment and presents them from the wider angle of science about botulinum toxin. In our opinion, anodermal blood flow depends not only on the "mechanical" force of sphincters but also on biochemical processes that occur in the fissure region.

Haemorrhoids are associated not with hypertrophy of the internal anal sphincter, but with hypertension of the anal cushions.

A combined manometric and ultrasonographic study of the internal anal sphincter was carried out in 20 patients with haemorrhoids and 20 age-matched normal controls. Mean(s.e.m.) basal anal pressure was significantly higher in patients than in controls, 62(4) versus 45(6) cmH2O (P less than 0.05), although there were no significant differences in mean maximum basal and squeeze pressures. During rectal distension 90 per cent of patients showed no reduction in anal pressure in the outermost anal channel, although the internal sphincter electromyogram was suppressed and the external sphincter electromyogram did not necessarily increase above baseline. The mean(s.e.m.) maximum residual pressure was significantly higher in patients, 70(6) versus 45(6) cmH2O (P less than 0.05). Direct pressure measurement in anal cushions exhibited abnormally high median pressure in patients compared with controls, 35 versus 10 cmH2O (P less than 0.001). Pressures recorded during coughing and straining were also significantly higher in patients than in controls (P less than 0.001). Ultrasonographic study of the anal canal revealed a clear image of the internal sphincter, the thickness of which could easily be measured. The mean(s.e.m.) thickness of the sphincter was not significantly different, 2.3(0.2) versus 2.1(0.1) mm, between patients with haemorrhoids and controls (P = 0.18). The absence of any significant differences in the internal sphincter thickness between normal subjects and patients with haemorrhoids suggests that the high anal pressure in patients with haemorrhoids is of vascular origin.

Ischaemic nature of anal fissure.

Microvascular perfusion of the anoderm was assessed by laser Doppler flowmetry in 27 patients with anal fissure. Anal pressure was recorded simultaneously. Both measurements were repeated 6 weeks after lateral internal sphincterotomy and compared with those obtained from 27 controls. Means(s.d.) maximum anal resting pressure was significantly higher in those with a fissure than in controls (121.07(24.48) versus 68.78(16.97) mmHg, P < 0.001). Anodermal blood flow at the fissure site was significantly lower than at the posterior commissure of the controls (0.46(0.20) versus 0.76(0.28) V, P < 0.001). The fissure healed in 24 patients within 6 weeks of sphincterotomy. In these patients a significant pressure decrease was noted (35 per cent) which was accompanied by a consistent rise in blood flow (65 per cent) at the original fissure site. The increased internal sphincter tone in patients with a fissure reduces anodermal blood flow at the posterior midline. Reduction of anal pressure by sphincterotomy improves anodermal blood flow at the posterior midline, resulting in fissure healing. These findings provide evidence for the ischaemic nature of anal fissure.

External and internal anal sphincter responses to rectal distension in normal subjects and in patients with idiopathic faecal incontinence.

The responses of the external anal sphincter and the internal anal sphincter to rectal distension were studied in 18 female patients who had idiopathic faecal incontinence with perineal descent and 11 female control subjects, by measuring pressures at six sites within the anal canal and the electrical activity of the external sphincter. The pressure profile in the normal anal canal, at rest, was asymmetric with the highest pressure recorded in the outermost channels. Rectal distension caused a transient increase in the activity of the external sphincter, which was associated with an increase in anal pressure, particularly in the outermost two channels. This was followed by a symmetrical reduction in anal pressure throughout the anal canal, caused by relaxation of the internal sphincter and shortening of the high-pressure zone. Two patterns of response were observed in the patients with idiopathic incontinence. Twelve patients (group 1) showed normal anal relaxation, but the maximum anal pressures recorded during rectal distension or a conscious squeeze were abnormally low, suggesting weakness of the external anal sphincter. The remaining six subjects (group 2), who were older than the group 1 patients, had much lower resting pressures and showed only external sphincter contraction in response to rectal distension, with no obvious internal sphincter relaxation. However, the maximum pressures recorded during a conscious contraction of the external sphincter were lower in this group than in the normal control subjects. These results suggest that group 2 patients have impaired internal anal sphincter tone, as well as external anal sphincter weakness. This may explain why all except one of the group 2 patients, compared with only 17 per cent of group 1 patients, reported incontinence to both solids and liquids.

Systemic levels of glyceryl trinitrate following topical application to the anoderm do not correlate with the measured reduction in anal pressure.

Topical 0.2 per cent glyceryl trinitrate (GTN) lowers resting anal pressure (RAP) and heals two-thirds of chronic anal fissures. Over 50 per cent of patients experience headache, presumably through systemic absorption, but the pharmacokinetics of GTN ointment are unknown. This study evaluated the systemic absorption profile of GTN, and correlation between plasma GTN levels, RAP, haemodynamic variables and side-effects. Thirty healthy volunteers were recruited with local medical school ethics committee approval. Continuous static anal manometry was performed for 10 min before and 2 h after application of 0.2 per cent GTN (0.5 g) to the anoderm. Blood samples were taken from an intravenous cannula, and pulse and blood pressure were measured before application of GTN, and 10, 20, 30, 40, 50, 60, 90, 120 and 180 min thereafter. Details of side-effects were recorded. GTN was detected in the plasma 10 min to 3 h after topical application. RAP was significantly reduced after 10 min, but had returned to pretreatment values by 120 min. Pulse was statistically unchanged during the study; systolic blood pressure was significantly lower 20-90 min after GTN application, and diastolic pressure was decreased throughout the study. Headaches were experienced by 14 of 30 volunteers after a median (range) of 41 (4-120) min, persisting for 74 (30-176) min, with an intensity score of 19 (5-30) mm represented on a 100-mm linear visual analogue scale. There was no correlation between plasma GTN concentration, RAP, and the onset, duration or intensity of headaches. Topical GTN acts locally on the internal anal sphincter; systemic levels do not contribute significantly to the reduction in RAP. There is marked interindividual variation in plasma GTN levels, and no correlation with haemodynamic variables and side-effects.

Alpha-1 adrenoceptor blockade: potential new treatment for anal fissures.

Patients with chronic anal fissures are known to have high resting anal pressures that return to normal after successful surgical treatment. Internal anal sphincter activity is increased by sympathetic excitatory innervation via alpha adrenoceptors. The objective of this study was to determine the effect of alpha-1 adrenoceptor blockade on anal sphincter pressure in patients with and without chronic anal fissures. The effect on the anal canal pressure profile of a single oral 20 mg dose of indoramin, an alpha-1 adrenoceptor antagonist, on seven patients with chronic anal fissure and six healthy patients without a fissure was investigated. Indoramin reduced anal resting pressures in those with anal fissure by a mean of 35.8 percent, from 106.9 +/- 22.15 cm H2O to 68.6 +/- 20.35 cm H2O, and in those without anal fissure by a mean of 39.9 percent, from 84.17 +/- 27.46 cm H2O to 52.17 +/- 24.78 cm H2O, after one hour. This pressure reduction persisted at three hours, and its magnitude is comparable to that obtained after internal sphincterotomy. The pressure reduction occurred over the whole length of the anal canal. It is proposed that alpha-1 adrenoceptor antagonists could be a suitable treatment for chronic anal fissure and other painful conditions where reduction in anal pressure is warranted.

Anal fissure: new concepts in pathogenesis and treatment.

The posterior commissure of the anal canal is less well perfused than the other segments of the anoderm. There is growing evidence that the increased activity of the internal anal sphincter, which is found in almost all patients with a chronic anal fissure, further decreases the anodermal blood supply, especially at the posterior midline. Reduction of anal pressure, either by anal dilatation or by lateral internal sphincterotomy, is the most important step in the treatment of chronic anal fissure. However, both procedures frequently result in permanent sphincter defects and subsequent continence disturbances. Recently, nitric oxide (NO) has been identified as the chemical messenger mediating relaxation of the internal anal sphincter. It has been shown that local application of exogenous NO donors such as nitroglycerin and isosorbide-di-nitrate reduces anal pressure and improves anodermal blood flow. This dual effect results in fissure healing in more than 80% of patients.

Anal manometry in patients with fissure-in-ano before and after internal sphincterotomy.

The motility pattern of the internal anal sphincter was estimated manometrically in 42 patients with fissure-in-ano before and after left lateral internal sphincterotomy (LAS). Resting anal pressure and anal pressure during straining were significantly higher in patients than in controls (132 +/- 21 SD cmH2O vs 81 +/- 14 SD cmH2O P < 0.0002 and 46 +/- 16 SD cmH2O vs 13 +/- 4 SD cmH2O P < 0.0005), but were normal after LAS. Slow waves were more common in fissure patients (86 +/- 6 SD% of total recording time vs 68 +/- 11 SD% of total recording time, P < 0.0002), but also became normal after successful treatment. The presence of ultra slow waves was also more common in fissure patients (P < 0.0001), and although it was significantly reduced postoperatively (P < 0.0001), it did not return to normal. Sampling was less frequent in fissure patients (P < 0.0001) and improved significantly after successful treatment (P < 0.0002). Rectal distension produced significantly less reduction in anal pressure in fissure patients as compared to controls (P < 0.01), but successful treatment returned the response to normal. There were 2 patients with anal fissure who did not heal after left LAS. Those patients and a further 5 patients with non healed fissures after left LAS showed the same pathological manometric features as before surgery. Their fissures were successfully treated by additional right lateral internal sphincterotomy. In conclusion, increased internal sphincter activity is probably an aetiological factor in fissure-in-ano, while successful LAS improves anal sphincter function.(ABSTRACT TRUNCATED AT 250 WORDS)

Voluntary relaxation of the external anal sphincter

In this study five volunteers with special training in anal sphincter exercise (Scandinavian Yoga School) managed voluntarily to reduce anal pressure. The mean reduction of anal pressure was 20 mm Hg. In one of the subjects, this was shown by manometry during low spinal anesthesia and electromyography to be caused by relaxation of the external anal sphincter.

Sympathetic nervous influence on the internal anal sphincter and rectum in man.

The effect of sympathetic nerve block and efferent stimulation of the sympathetic nerves on anorectal motility was studied in 21 patients undergoing operation for rectal carcinoma. Anal pressure and rectal volume were simultaneously recorded before and after epidural anaesthesia and during nerve stimulation. Efferent electrical stimulation of the presacral hypogastric nerves (HGN) elicited a contraction of the internal anal sphincter (IAS) in 13 out of 15 patients. The contraction was preceded by a relaxation in seven patients. In the rectum stimulation of the HGN caused variable responses. A weak contraction was the most frequent response. Efferent stimulation of the periarterial lumbar colonic nerves (LCN) elicited a clear-cut contraction of the IAS, while rectal motor responses were only occasionally observed. Epidural anaesthesia encompassing the thoraco-lumbar region (EDA), when used to block the sympathetic discharge to the IAS and the rectum, caused a reduction of anal pressure (28 +/- 11%) and an increased rectal tone. The results imply that the human IAS receives a sympathetic excitatory innervation via both the HGN and the LCN. Furthermore, it appears that the HGN convey inhibitory fibres to the IAS. The rectal responses to EDA and sympathetic nerve stimulation also indicate the presence of both excitatory and inhibitory neurones in the sympathetic nerve supply to the rectum in man.

Prospective trials of minor surgical procedures and high-fibre diet for haemorrhoids.

Two hundred and sixteen consecutive patients seen for the first time with symptomatic haemorrhoids entered trials of conservative and minor surgical treatment. They were divided into two groups according to their pretreatment maximal anal pressure. Patients with pressures of 100 cm H2O (73.7 mm Hg) or more (108 patients) were treated by anal dilatation (37), sphincterotomy (34), or high-fibre diet (37). Four and 12 months later anal dilatation had produced significantly better results than sphincterotomy or diet. Furthermore, anal dilatation was the only treatment associated with a significant reduction in anal pressure at four and 12 months. Patients with pressures under 100 cm H2O (108 patients) were treated by rubber-band ligation (35), cryosurgery (36), or diet (37). Four and 12 months later significantly more patients were improved by rubber-band ligation than by cryosurgery or diet. These results suggest that haemorrhoids in patients with excessive activity of the internal anal sphincter are best treated by anal dilatation and that in all other patients rubber-band ligation is the treatment of choice.