Do we have to stop anticoagulant and platelet-inhibitor treatments during proctological surgery?

AIM: This prospective observation study evaluated the incidence of secondary bleeding after proctological surgery without interruption of oral anticoagulant or platelet-inhibitor treatments. METHOD: The number of episodes of postoperative bleeding was identified prospectively from the day of surgery to the last follow-up visit in consecutive patients operated on during 2010 in two units dedicated to proctology. RESULTS: A total of 2513 procedures were performed in 2314 patients (1379 men), 46 ± 16 years of age. Secondary bleeding occurred after 115 (4.6%) procedures, no later than day 24 after surgery, requiring rehospitalization in 86% of cases and further surgery and/or transfusion in 36%. The highest frequency was noted after surgery for haemorrhoids (haemorrhoidopexy, 7.9%; haemorrhoidectomy, 6.2%) (P = NS and transanal excision of rectal tumours (6.5%). On multivariate analysis, the frequency was significantly increased by clopidogrel (15%) [relative risk (RR) = 10). In patients on oral anticoagulants, bleeding occurred in 23% (RR = 5.8) if the anticoagulants were not interrupted and in 57% (RR = 42) if the anticoagulants were discontinued and replaced with heparin. CONCLUSION: During proctological surgery the overall risk of postoperative bleeding is low, but it can occur up to 3 weeks after surgery and is often severe. Maintenance treatment with oral anticoagulants is the most important risk factor, aggravated by a change to heparin. Clopidogrel also significantly increases the bleeding risk.

Prospective survey of secondary bleeding following anorectal surgery in a consecutive series of 1,269 patients.

INTRODUCTION: As little data is available about secondary bleeding after proctological surgery, we conducted a specific survey. PATIENTS AND METHODS: Patients operated between November 2008 and April 2009 were prospectively included. Patients were followed until last visit (day 21-28). Severity of bleeding was low (at home stay), moderate (hospitalisation for observation), or severe (transfusion, and/or homeostasis in operating room). RESULTS: Included were 1269 patients: haemorrhoidectomy/pexy 527 (41%), fistula treatment 273 (21%), fissurectomy 197 (15%), perianal and pilonidal abscesses 124 (10%), others 148 (12%). Before surgery 78 patients were under long-term treatment with antiplatelet or anticoagulant therapy. Seventy-eight patients (6%) demonstrated 85 bleeding events. Severity rate was: low 22%, moderate 51%, and severe 27%. Ninety-five percent of events occurred before day 15. Univariate study showed increased risk after haemorrhoidopexy (P<10-3) and anticoagulant treatment (P = 0.002), decreased risk after fissurectomy and fistulotomy (P<10-3), and no relation with age, sex or operator. After multivariate study only relationship with anticoagulant treatment remained significant. CONCLUSION: Secondary bleeding occurred in 6% of patients after proctological surgery, requiring a readmission and/or an active treatment in about 75%. Treatment with anticoagulant exposed to increased bleeding frequency.

[Repair of rectocele using the Stapled TransAnal Rectal Resection (STARR) technique: intermediate results from a multicenter French study]. / Traitement de la rectocèle par résection rectale transanale à la pince mécanique: résultats à moyen terme d'une étude multicentrique en France.

BACKGROUND: Stapled transanal rectal resection is a new alternative for the treatment of outlet obstruction syndrome. The aim of this study was to assess its feasibility and safety in a multicenter context. MATERIALS AND METHOD: The study had a retrospective design and included 102 patients who were operated in 5 centers. All patients complained of symptomatic outlet obstruction. Surgical technique involved a double hemi-circumferential rectal stapling according to the technique described by Longo. Mean follow-up was 17.2 months. RESULTS: The STARR procedure was done in 100 patients (2 patients had a non relaxing sphincter preventing anal dilatation). Immediate postoperative morbidity included bleeding in 4 cases (4%) and rectal stenosis in 3 cases (3%). The main postoperative medium-term complaints were urge to defecate (34%) which was regressive in most patients and de novo incontinence to flatus (9%). Nevertheless, results were considered favorable in 85% of patients. CONCLUSION: This multicenter study, reporting the results of the largest published series, suggests that the STARR technique is feasible and safe in the medium term for the treatment of rectocele. Occurrence of adverse events such as incontinence to flatus should be better evaluated by future studies with longer follow up in order to assess the actual place of STARR in the treatment of rectocele or outlet obstruction.

Low hemorrhoidopexy staple line does not improve results and increases risk for incontinence.

BACKGROUND: The ability of stapled hemorrhoidopexy (SH) to cure hemorrhoidal symptoms appears to depend on patient characteristics and operative technique. We assessed the association between outcome of SH and patients' characteristics and procedure parameters (associated procedure, suture line height, doughnut size, presence of malpighian tissue or smooth muscle in specimen). METHODS: A total of 68 consecutive patients (56 males) were prospectively operated by 3 different surgeons. Hemorrhoids were grade II (6%), grade III (76%) or grade IV (18%). RESULTS: At a mean 32-week follow-up (range, 9-77), symptoms had resolved in 77% of patients, independently of any operative or clinical parameter. New onset anal incontinence occurred in 11 men (17%): all had urgency, with flatus and liquid stool incontinence in two, and flatus incontinence and mucus soiling in one. Univariate analysis revealed that persistent incontinence was associated with a staple line <6.5 mm from the dentate line, doughnut height <22 mm, and congestive external hemorrhoids; it was also operator dependent (p<0.05). At the 4-week follow-up, 19% of patients had persisting symptoms but only 8% had a demonstrable mucosal prolapse. CONCLUSION: Although the success rate of SH may not be influenced by technical variations, risk for moderate incontinence is elevated when the stapled line is low.

[Postoperative pain and long-term results after hemorrhoidal treatment with anopexy]. / Vécu de la douleur postopératoire et résultats à long terme après chirurgie hémorroïdaire par anopexie.

AIMS: Anopexy allows treatment of hemorrhoidal symptoms with a less painful postoperative course. This information is important for the patient, but may lead to dissatisfaction if pain level is higher than expected. To evaluate perceived pain and physical limitation levels in relation to patient's expectation. Evaluate long-term functional results. RESULTS: Sixty-eight consecutive patients (56 males) were prospectively included. Distribution of haemorrhoid grades were 4 grade 2 (6%), 52 grade 3 (76%) and 12 grade 4 (18%). Postoperative pain level was less or equal than expected for 85% of patients, with a better acceptance superior to 45 years. Physical limitation was equally or less important than expected for 89%. At the 32 weeks follow-up hemorrhoidal symptoms were present in 23%, uninfluenced by any patient's or operative characteristics. Incontinence with urgency was reported by 17%. Presence of an alliterated continence was linked to stapled line inferior to 6,5 mm from pectineate line, doughnut height inferior to 22 mm, external hemorrhoids and related to surgeon. CONCLUSION: Pragmatic information, although vague, about postoperative pain does not expose to patient's dissatisfaction. Functional results are not influenced by technical variation. Continence alterations are not severe, but frequent when stapled line is too close from pectineate line.

Low rectal volumes in patients suffering from fecal incontinence: what does it mean?

BACKGROUND: Rectal perception and adaptation to distension are widely heterogeneous in subjects with faecal incontinence. AIM: To quantify rectal physiology in patients with incontinence and low maximum rectal volume, according to AGA guidelines on anorectal testing techniques. PATIENTS AND METHODS: 148 patients (12 men, 136 female) with incontinence to liquid and/or solid stools were investigated. Distending isobaric procedures were carried out using an electronic barostat in order to analyse perception and adaptation of the rectum. RESULTS: Pain during isovolumic rectal distension at a level of 100 mL or less was experienced in 21 subjects (14.2%). As defined by isobaric distensions, incontinent patients with low MTV had more frequently a hypocompliant rectum (62%) when compared with those with higher MTV (31%, P = 0.046). Perception scores tended to be higher at each step of distending rectal pressure: incontinent patients with low MTV had more frequently a hypersensitive rectum (48%) when compared with those with normal or high MTV (24%, P = 0.035). Only four of 21 incontinent subjects with low MTV had an isolated hypersensitive rectum. CONCLUSION: Both sensitivity and compliance are altered in patients with low MTV. A more extensive study of the role of sensory and compliance aspects of subjects with incontinence is warranted.

Lack of effficacy of botulinum toxin in chronic anal fissure.

BACKGROUND AND AIM: Hypertonicity of internal anal sphincter plays a major role in the persistence of chronic anal fissure. Botulinum toxin could induce internal anal sphincter relaxation without the adverse effects of surgery (long-term faecal incontinence) or topical nitrates (anal burning, headaches, hypotension). METHODS: We conducted a placebo-controlled, randomised, double-blind study to assess the efficacy of a single injection of botulinum toxin in the internal anal sphincter of patients with chronic anal fissure in six ambulatory care clinics. Eligibility criteria included a mean value of post-defecation anal pain >or= 30 mm on a 100 mm visual analogue scale over the week preceding inclusion. Main endpoint was the proportion of patients with symptomatic improvement during the fourth week after inclusion (post-defecation anal pain below 10 mm). RESULTS: Forty-four patients (22 in each group) were included. At inclusion, there was no significant difference between groups on age, sex ratio, pain duration, post-defecation anal pain, analgesic consumption and stool frequency. Ten (45%) and 11 (50%) patients reported symptomatic improvement on the main endpoint (P=0.76) in placebo and botulinum toxin groups, respectively. Ten patients (five in each group) had healed fissure at week 4 and ten patients (five in each group) required surgical treatment between weeks 4 and 12. Similarly, there was no significant difference between groups on other variables between weeks 4 and 12. CONCLUSIONS: The efficacy of a single injection of botulinum toxin in the internal anal sphincter does not differ from that of a placebo in patients with chronic anal fissure.

[Local excision with postoperative radiotherapy for T2 or T3 distal rectal cancer. Long-term results]. / Exérèse locale avec radiothérapie préopératoire dans les cancers T2 ou T3 du bas rectum. Résultats à long terme.

STUDY AIM: To evaluate, in a prospective study of a cohort of patients, the local recurrence rate of T2 or T3 rectal cancers treated by transanal excision after preoperative irradiation. PATIENTS AND METHODS: Between 1992 and 1999, 34 patients were treated after radiotherapy by a local excision for a distal rectal carcinoma limited to (stage T2) or invading through the muscular layer (stage T3). Four patients were excluded either for palliative treatment or lost for follow-up. Thirty patients were included in the study (8 uT2, 8 uT3, 14 undetermined preirradiation stage). RESULTS: After a 74-month mean follow-up (median: 46), the 5-year local recurrence rate was 33%. Even among subgroups of patients with a significant risk factor for local recurrence (size > 40 mm, clear margin < 2 mm, uT3 stage versus uT2) there were no benefits from irradiation. CONCLUSION: Local excision of T2 or T3 rectal cancers is associated with an elevated local recurrence rate. This result is demonstrated even after adjunction of a preoperative irradiation. So, local treatment must be restricted to clearly informed patients who definitively refuse a radical intervention.

[Quality of life, symptoms of dyschezia, and anatomy after correction of rectal motility disorder]. / Qualité de vie, symptômes de dyschésie et anatomie après correction d'un trouble de la statique rectale par voie basse.

AIM OF THE STUDY: To evaluate the quality of life of patients suffering from dyschezia and its correlation with symptomatic complaints and anatomical abnormalities, before and after elective surgery for rectal static disorder. PATIENTS AND METHODS: A prospective study was conducted using a general quality of life questionnaire (SF36) and a constipation specific score (PAC-QoL), a dyschezia symptom score, and defecography. RESULTS: Thirty-eight female dyschesic patients (mean age 54 years) underwent surgery for rectocele with (n=16) or without (n=14) internal rectal prolapse, an isolated internal rectal prolapse (n=3), or a total rectal prolapse (n=5). Preoperative quality of life was low, correlated with the intensity of dyschezia. Seven months after surgery, quality of life and dyschezia improved independently of the amplitude of the anatomical correction. More items improved in the constipation specific score than on the quality of life questionnaire; they were correlated with the course of dyschezia symptoms. Neither incontinence nor irritable bowel syndrome affected evolution of the symptoms. CONCLUSION: Surgery improved initially low quality of life and symptomatic complaints in patients with dyschezia and a rectal static disorder, independently of anatomic repair. Differences in changes observed in the PAC-QoL and SF36 suggest different fields of application.

Perception of and adaptation to rectal isobaric distension in patients with faecal incontinence.

BACKGROUND: Perception of, and adaptation of the rectum to, distension probably play an important role in the maintenance of continence, but perception studies in faecal incontinence provide controversial conclusions possibly related to methodological biases. In order to better understand perception disorders, the aim of this study was to analyse anorectal adaptation to rectal isobaric distension in subjects with incontinence. PATIENTS/METHODS: Between June 95 and December 97, 97 consecutive patients (nine men and 88 women, mean (SEM) age 55 (1) years) suffering from incontinence were evaluated and compared with 15 healthy volunteers (four men and 11 women, mean age 48 (3) years). The patients were classified into three groups according to their perception status to rectal isobaric distensions (impaired, 22; normal, 61; enhanced, 14). Anal and rectal adaptations to increasing rectal pressure were analysed using a model of rectal isobaric distension. RESULTS: The four groups did not differ with respect to age, parity, or sex ratio. Magnitude of incontinence, prevalence of pelvic disorders, and sphincter defects were similar in the incontinent groups. When compared with healthy controls, anal pressure and rectal adaptation to distension were decreased in incontinent patients. When compared with incontinent patients with normal perception, patients with enhanced perception experienced similar rectal adaptation but had reduced anal pressure. In contrast, patients with impaired perception showed considerably decreased rectal adaptation but had similar anal pressure. CONCLUSION: Abnormal sensations during rectal distension are observed in one third of subjects suffering from incontinence. These abnormalities may reflect hyperreactivity or neuropathological damage of the rectal wall.

[Causal assessment of drug-induced acute colitis. A prospective study of 58 consecutive cases]. / Responsabilité des médicaments dans la survenue des colites aiguës. Résultats d'une étude prospective de 58 cas consécutifs.

AIMS: The causal effect of drugs is underestimated in patients with inflammatory bowel disease. The aim of this study was to assess the causal implication of drugs in acute colitis. METHODS: A prospective study was conducted in 58 consecutive patients with an acute inflammation of the colonic mucosa. Recent drug intake was recorded and possible causal effects were analyzed exhaustively with respect to both intrinsic and bibliographic criteria. RESULTS: Causal assessment scores were high for 57 drugs and 41 patients. Drug-induced acute colitis was diagnosed in 35 cases. In 7 patients, physician practice had not taken into account drug use despite probable drug involvement. The main drugs implicated were antibiotics (n = 42) and non steroidal anti-inflammatory drugs (n = 10). CONCLUSION: Acute colitis is mainly induced by drugs.

Octreotide acts on anorectal physiology: a dynamic study in healthy subjects.

BACKGROUND: Somatostatin is localized in the intestinal and pelvic nerves of the anorectum and it seems to act as an important neurotransmitter. However, previous analyses of octreotide (a somatostatin analog) effects on anal function showed conflicting results. By use of a dynamic model in healthy subjects, with comparison to the myogenic effect of glucagon, the aim of our study was to further investigate the pharmacologic targets of octreotide. METHODS: This was a placebo-controlled, randomized, double-blinded crossover study performed in 12 healthy volunteers who received octreotide, glucagon, or placebo intravenously on separate days. During each sequence, several pressure steps in 3 different protocols of rectal isobaric distension were applied with an electronic barostat. Manometric responses of the anal canal, adaptative volumes, and perception scores of the rectum were recorded. RESULTS: During both phasic and stepwise distensions, a significant drug effect was encountered at the anal level. Compared with placebo, octreotide significantly increased pressures at both upper and lower levels of the anal canal. In contrast, glucagon decreased pressures at the upper part of the anal canal. Octreotide significantly decreased rectal volumes to phasic distension, but glucagon did not induce any change on rectal adaptation. In addition, neither drug modified perception scores. CONCLUSION: This study suggests that octreotide acts on reflex arcs and rectal myenteric neurons rather than on anal myogenic targets that respond to glucagon.

Rectal adaptation to distension in patients with overt rectal prolapse.

BACKGROUND: High recovery rates of continence are observed after surgical procedures for rectal prolapse. Increases in rectal compliance but no obvious rise in anal pressures have been reported. The authors' hypothesis was that decreased rectal adaptation to distension may contribute to incontinence in patients suffering from overt rectal prolapse. METHODS: This was a prospective study conducted in 20 consecutive incontinent patients suffering from overt rectal prolapse with no mucosal change (two men and 18 women; mean(s.e.m.) age 50(3) years). They were compared with 20 age- and sex-matched patients with incontinence without rectal prolapse and ten age- and sex-matched healthy volunteers observed during the same period. The subjects were submitted to phasic isobaric distension of the rectum with an electronic barostat. Anal pressures, perception scores and rectal volumes were recorded at six different preselected pressures. RESULTS: Compared with healthy subjects, maximum rectal volumes (mean(s.e.m) 98(6) versus 167(11) ml; P= 0.005), volumes related to compliance (56(5) versus 100(9) ml; P= 0.004) and tone (41(3) versus 67(4) ml; P = 0.003) were decreased significantly in the rectal prolapse group. Prolapse and incontinence groups did not differ significantly with respect to rectal adaptation for all three parameters and steps of distension considered. CONCLUSION: Patients suffering from overt rectal prolapse had markedly impaired rectal adaptation to distension which may contribute to incontinence.

Effects of cholinergic agents on anorectal physiology.

BACKGROUND: Despite their potential therapeutic benefit, the effects of cholinergic agents on anal function have been poorly investigated. AIM: To analyse the effects of neostigmine and atropine on anorectal responses to rectal isobaric distension. METHODS: This was a placebo-controlled, randomized, double-blind crossover study, performed in 12 healthy volunteers who received intravenously, on 3 separate days, neostigmine, atropine or the placebo. During each day of the experiment, seven pressure steps (ranging from 1 to 31 mmHg) in three different protocols of rectal isobaric distension (phasic, stepwise and tonic) were applied using an electronic barostat. Manometric responses of the anal canal, adaptative volumes and perception scores of the rectum were recorded. RESULTS: During stepwise distension, a significant drug effect was encountered at the anal level. No drug effect was observed on the other investigated parameters (rectal volumes and rectal perception scores) or for the other modes of distension. Compared to placebo, neostigmine significantly decreased pressures at the upper level of the anal canal for both recto anal inhibitory reflex and mean resting pressures. In contrast, atropine significantly increased pressures at the lower part of the anal canal but did not modify upper anal pressures. CONCLUSION: The present study suggests that cholinergic effects result more from an indirect action on intermediate neurotransmitters and rectal myenteric neurons, than from a direct action on anal targets.

Anal lesions: any significant prognosis in Crohn's disease?

AIM: Work-up of anoperineal lesions usually includes indices of clinical activity as well as diagnostic criteria of Crohn's disease but their prognostic implication remains unclear. This prospective study was conducted in order to evaluate the overall incidence of anoperineal lesions and their relation to the natural history of underlying intestinal Crohn's disease with special reference to the steroid-dependent state of the patients. PATIENTS AND METHODS: One hundred and one patients (46 males, 55 females, aged 34 +/- 14 years; range: 15-79) were consecutively referred to our institution (May 1991 to May 1994) for intestinal symptoms related to Crohn's disease (mean duration 66 +/- 66 months). They all underwent a proctological examination regardless of perineal symptoms. The Cardiff classification was used to describe anoperineal lesions. Patients with anal lesions (64) differed from those without (37): male predisposition (53% vs. 32%, P<0.05), more frequent rectal involvement (75% vs. 24%, P<0.001) and more acute lesions observed at proctoscopic examination (42% vs. 16%, P<0.05). Age of onset, surgical past history of Crohn's disease, colonic or ileal involvement, or Harvey-Bradshaw score were not different between groups. RESULTS: Patients with anal ulceration (43) as compared to patients having anal involvement without ulceration experienced pain more frequently (constant pain: 56 vs. 14%; defecatory pain: 35 vs. 19%) and a more severe evolution of intestinal (40 vs. 22%, P<0.05) and anal (42 vs. 12%, P<0.05) involvement. In those with an aggressive ulceration (U2, 28 patients), daily stool frequency (5.1 +/- 3 vs. 3.6 +/- 2.5, P<0.05) and clinical score (9 +/- 5 vs. 7 +/- 3) were more pronounced. Steroid therapy dependency occurred more frequently in the group with anal ulceration (35 vs. 16% and 40 vs. 17%, respectively, P<0.05). Similar associations were observed for cases of anal involvement (34 vs. 5%, P<0.01) and azathioprine was more frequently required (39 vs. 5%, P<0.01) than in those free of anal lesions. During follow-up, eight other patients required azathioprine (steroid dependence in six) and seven of them had anal lesions at referral. At the endpoint of the study, one out of two patients with anal lesions required azathioprine most often due to steroid dependency of the intestinal involvement (30/64 vs. 4/37, P<0.005). CONCLUSION: Anal ulcerations are a reliable severity index of Crohn's disease in both short- and long-term prognosis but their link to the steroid status of the intestinal disease remains unclear.

First European case of gastroenteritis and bacteremia due to Vibrio hollisae.

Vibrio hollisae is a pathogenic Vibrio species known to cause gastroenteritis in humans after the consumption of shellfish. All cases of infection reported previously were restricted to the Atlantic and Pacific coasts of the United States. A case of gastroenteritis and bacteremia in a previously healthy 76-year-old man who ate cockles from the Quiberon Bay in Brittany, France, is described. This is the first report of Vibrio hollisae infection in Europe.

Increased liver iron stores in patients with hepatocellular carcinoma developed on a noncirrhotic liver.

Iron was systematically studied in the nontumorous liver of 24 patients with hepatocellular carcinoma (HCC) developed on a noncirrhotic liver compared with 4 control groups (cirrhosis with and without HCC, liver metastasis, and normal liver) matched according to age, sex, and presence of chronic alcoholism. Assessment of liver iron was made by (1) histology according to iron distribution and quantification (total iron score: 0 to 60), and (2) biochemistry (liver iron concentration-N < 36 mumol/g) with calculation of the hepatic iron index (liver iron concentration/age). Patients with hepatocellular carcinoma developed on a noncirrhotic liver presented with (1) histological iron in 83%; (2) parenchymal iron excess significantly more frequent (90%) than in controls; (3) total iron score (15 +/- 12) and liver iron concentration (81 +/- 96) significantly greater than in controls; and (4) hepatic iron index significantly increased (1.4 +/- 1.5) when compared with control groups, except for the hepatocellular carcinoma complicating cirrhosis group (0.9 +/- 1.1). This study (1) shows a mild but unquestionable parenchymal iron excess in the nontumorous liver of most patients presenting with hepatocellular carcinoma developed on a noncirrhotic liver and, at a lesser extent, on cirrhosis, (2) should incite others to study the putative role of iron in the development of liver cancer both in patients with cirrhosis and those without it, whatever the cause of the underlying liver disease, and (3) add argument to take into account and to treat any liver iron excess, even when mild.

Anismus and biofeedback: who benefits?

BACKGROUND: Biofeedback is the main treatment for dyschezia in patients with anismus, but retraining may fail because of the frequent association of pelvirectal disorders with anismus. We set out to identify indices of biofeedback failure in the treatment of anismus. PATIENTS AND METHODS: From May 1990 to May 1993, 27 patients (20 women and seven men; median age 46 years) with anismus in which dyschezia was not improved by laxative agents were enrolled in a biofeedback retraining programme. All patients underwent proctologic examination, anal manometry and defecography. Anismus was defined as an increase in anal pressure during attempted defecation in conjunction with an impairment of rectal emptying as assessed using an objective test (barium paste expulsion). Associated disorders were encountered frequently. These included abnormal perineal descent (22 cases), large rectocoele (12 cases), high-grade rectal prolapse (six cases), abnormally high anal canal pressures at rest (seven cases) and abnormal rectal response to inflation (20 cases). Anismus was the sole abnormality in 12 patients when perineal descent, low-grade prolapse and abnormal rectal sensations were not taken into account. RESULTS: Biofeedback retraining did not suppress dyschezia in 13 out of 27 patients. Neither associated disorders (rectocoele, rectal prolapse, abnormal perineal descent, anal pressure and abnormalities of rectal sensation) nor a relevant past history (hysterectomy, laxative abuse, use of antidepressive agents) were encountered more frequently in these 13 patients than in the other 14. The duration of symptoms before treatment was significantly longer in the group unresponsive to biofeedback retraining (81 +/- 61 compared with 33 +/- 34 months for the responsive group, P < 0.01), but the total duration of symptoms and the number of retraining sessions attended did not differ significantly between the two groups. CONCLUSIONS: (1) Extensive examination (defecography and manometry) before biofeedback retraining of anismus is not mandatory because the failure of retraining (48%) is not related to the presence of associated pelvirectal disorders. (2) A long past history of dyschezia seems to provide an index of the failure of biofeedback retraining.