Endoscopic perforation of the colon: lessons from a 10-year study

Small and diminutive polyps detected at screening CT colonography: a decision analysis for referral to colonoscopy

OBJECTIVE

The objective of this study was to assess the clinical and economic impact of colonoscopic referral for small and diminutive polyps detected at CT colonography (CTC) screening.

MATERIALS AND METHODS

A decision analysis model was constructed incorporating the expected polyp distribution, advanced adenoma prevalence, colorectal cancer (CRC) risk, CTC performance, and costs related to CRC screening and treatment. The model conservatively assumed that CRC risk was independent of advanced adenoma size. The number of diminutive (< or = 5 mm), small (6-9 mm), and large (> or = 10 mm) CTC-detected polyps needed to be removed to detect one advanced adenoma or prevent one CRC over a 10-year time horizon was calculated. The cost-effectiveness of polypectomy was also assessed.

RESULTS

The estimated 10-year CRC risk for unresected diminutive, small, and large polyps was 0.08%, 0.7%, and 15.7%, respectively. The number of diminutive, small, and large polyps needed to be removed to avoid leaving behind one advanced adenoma was 562, 71, and 2.5, respectively; similarly, 2,352, 297, and 10.7 polypectomies would be needed, respectively, to prevent one CRC over 10 years. The incremental cost-effectiveness ratio of removing all diminutive and small CTC-detected polyps was $464,407 and $59,015 per life-year gained, respectively. Polypectomy for large CTC-detected polyps yielded a cost-saving of $151 per person screened.

CONCLUSION

For diminutive polyps detected at CTC screening, the very low likelihood of advanced neoplasia and the high costs associated with polypectomy argue against colonoscopic referral, whereas removal of large CTC-detected polyps is highly effective. The yield of colonoscopic referral for small polyps is relatively low, suggesting that CTC surveillance may be a reasonable management option.

Mucoadhesive micropatterns for enhanced grip

The main challenge in designing diagnostic devices able to move along the colon is their locomotion method. Manipulating friction with the colonic surface is a key requirement for their safe and atraumatic propagation. One possible solution is to generate friction by means of adhesive forces. For this purpose, a diagnostic device can be covered with mucoadhesive films that stick to the mucus layer of the colonic surface and generate high static friction. This paper investigates whether micropatterning the mucoadhesive films is able to enhance the grip with the colonic surface even more than flat mucoadhesive films. This idea is inspired by the sponge-form adhesive secretion of sea stars which is released by numerous tubular feet. Experiments in vitro showed that the frictional performance of mucoadhesive micropatterns exceed that of non-patterned mucoadhesive films. Moreover, the grip achieved by mucoadhesive micropatterns is far higher than the grip generated by non-mucoadhesive micropatterns made of an elastomeric material. Mucoadhesive micropatterned films also avoid the risk of damaging the colonic surface, since they interact only with the mucus layer and leave the colonic epithelium unaffected.

'How compliant do we want to be with the colonoscopy surveillance guidelines?'

OBJECTIVE

To assess the referral practice for surveillance colonoscopy amongst clinicians and to measure whether practice was inline with the current Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Society of Gastroenterology (BSG) guidelines.

METHOD

A questionnaire was sent to members of the ACPGBI.

RESULTS

A total of 195 (49%) clinicians responded, providing information on their referral habits with comments on where they deviated from the guidelines.

CONCLUSIONS

The BSG and ACPGBI guidelines are well established amongst clinicians and generally accepted as best practice, however, the majority of clinicians deviate from the guidelines for particular clinical scenarios. In fact only 18% of respondents followed all recommendations for surveillance colonoscopy for patients with polyps, previous cancers and a family history.

Iatrogenic perforation associated with therapeutic colonoscopy: a multicenter study in Japan

BACKGROUND AND AIM

Colonic perforation is the serious accidental complication. The aim of this study is to analyze the clinical presentation and management of recent iatrogenic perforations during therapeutic colonoscopy.

METHODS

Consecutive patients referred to four academic cancer centers in Japan were retrospectively reviewed using each center's endoscopy database of medical records. Data was obtained by means of an extensive data collection sheet. Since we evaluated the data including iatrogenic perforation during newly developed therapeutic procedure such as endoscopic submucosal dissection (ESD) or hemoclips, the collection of patient data was set from the period of the beginning of ESD technique in each hospital in this study.

RESULTS

The overall rate of occurrence of perforation was 0.15% (23/15, 160). Perforation rate for EMR (0.58%) showed a significantly higher rate (P < 0.0001) than that for hot biopsy and polypectomy. The rate for ESD (14%) showed a markedly higher rate (P < 0.0001) than that for other standard procedures. Of those perforations, endoscopic clipping was performed in 56.5% of the patients, and conservative treatment was successful in 100% of the patients with successful closure. Both CT scan findings and serology results (WBC, CRP) after perforation were poor predictors for need for surgery as opposed to conservative management.

CONCLUSIONS

Further improvements in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms, because perforation rate for ESD shows a markedly higher. Conservative management may be possible in patients who have undergone complete endoscopic clipping.

Sigmoid colon perforation at CT colonography secondary to a possible obstructive mechanism: report of a case

We report a case of colonic perforation in CT colonography, which was observed in a sigmoid colon segment contained within an inguinal hernia. At surgery, apart from the perforation, a normal large-bowel wall was found. Although rare, perforation may occur in patients with normal bowel wall, possibly resulting from a mechanical strain caused by gaseous overdistention. Radiologists performing the procedure must be aware of this possibility.

Follow-up after colorectal polypectomy: a benefit-risk analysis of German surveillance recommendations

OBJECTIVE

For colorectal screening patients a mean gain of life time was previously calculated of about 30-50 days. Different recommendations for recognising at-risk groups and defining surveillance intervals after an initial finding of colorectal adenomas have been published. However, no benefit-risk analysis regarding to specific long-term effects of follow-up has been reported to date.

MATERIALS AND METHODS

A Markov model based on time-dependent transition possibilities was developed to perform a benefit-risk analysis of the risk-related surveillance recommendations based on the Erlangen Registry of Colorectal Polyps (ERCRP) in comparison with the recommendation of the German Society of Gastrointestinal Diseases and Nutrition (DGVS). The outcome was calculated for a 50-year-old patient with 30 years of follow-up after initial polypectomy. The data used in this model were taken from different sources, namely the ERCRP, the German Study Group of Colorectal Cancer, the German Statistical Yearbook, and from meta-analyses of studies reporting data on complications and sensitivity of colonoscopy.

RESULTS

Patients under surveillance have a mean lifetime gain of 98 (ERCRP) and 110 (DGVS) days compared with those who do not come for surveillance. 84% and 94% of deaths from colorectal carcinoma (CRC) could be prevented if patients were followed up according to the recommendations of the ERCRP and the DGVS, respectively. Less colonoscopies are needed to prevent one death from CRC following the recommendations of the ERCRP (221) than those of the DGVS (283). The risk of death due to colonoscopy for patients during follow-up is about 0.05% lifetime risk. Sensitivity analysis showed the stability of the results under a wide range of reasonable variations of relevant parameters. In a pessimistic one-way sensitivity analysis regarding compliance, effectiveness was reduced to one third.

CONCLUSION

Surveillance using colonoscopy is an effective tool for preventing CRC after colorectal polypectomy, especially if a good compliance is assumed. The effectiveness is higher following the recommendations of the DGVS, but more colonoscopies are needed.

Colonoscopic perforation

Perforation is an uncommon but important complication of colonoscopy. This review looks at the incidence, clinical features, diagnosis and treatment of this condition.

Pneumoretroperitoneum, pneumomediastinum, peumopericardium, and subcutaneous emphysema after colonoscopic examination

Colonoscopy is regarded as a relatively safe procedure and is widely performed. However, complications such as bleeding, perforation, and coagulation syndromes can occur during colonoscopy. Although bowel perforation is as rare as 0.4-1.9% of cases, it is the most serious and awful adverse event which can lead to a death. Colon perforation may occur as either intraperitoneal or extraperitoneal, or in combination. Right subdiaphragmatic free air suggests intraperitoneal perforation while pneumoretroperitoneum, pneumomediastinum, pneumopericardium, and subcutaneous emphysema suggest extraperitoneal perforation. Combined intraperitoneal and extraperitoneal perforation is very rare. Herein, we present a case of combined intraperitoneal and extraperitoneal colon perforation which manifested as pneumoretroperitoneum, pneumomediastinum, pneumopericardium, and subcutaneous emphysema. The lesion was closed with endoscopic clipping.

Recording forces exerted on the bowel wall during colonoscopy: in vitro evaluation

A novel system for distributed force measurement between the bowel wall and the shaft of a colonoscope is presented. The system, based on the piezoresistive method, involves the integration of soft miniature transducers to a colonoscope to enable a wide range of forces to be sensed. The attached sensing sheath does not restrict the propulsion of the colonoscope nor notably alter its flexibility. The addition of the sensor sheath increases the colonoscope diameter by 15-20% depending on the type of the colonoscope (adult or paediatric). The transducer's accuracy is +/-20 grammes if it is not subjected to extensive static forces. Under large static force conditions the errors may increase to +/-50 grammes. The tactile force measuring sensors have provided preliminary results from experiments on a model of the large bowel. The force measurements confirm the predictions on the location and magnitude of the forces and that most of the forces are exerted whilst the instrument is looping.

Endoluminal suturing may overcome the limitations of clip closure of a gaping wide colon perforation (with videos)

BACKGROUND

It is unclear whether large gaping perforations of the colon can be closed by the endoluminal route.

OBJECTIVE

To evaluate the feasibility and the outcome of closure of large perforations of colon with clips and sutures by using through-the-endoscope novel devices.

DESIGN

Prospective animal study.

SETTING

University hospital.

PATIENTS

Ten pigs.

INTERVENTIONS

Closure of a 4-cm full-thickness colon perforation freshly created by an insulated-tip knife with the InScope Multi-Clip Applier (n = 6) and with the tissue approximation device (n = 4).

MAIN OUTCOME MEASUREMENTS

(a) Technical feasibility of closure, (b) clinical monitoring for 2 weeks, (c) necropsy (day 14), (d) healing by a dye-leak test and histology.

RESULTS

Endoluminal closure of a 4-cm-long colon perforation was successful in 9 of 10 animals. The clips failed to close a gaping wide colon perforation in 1 animal. The sutures were successful in the closure of both nongaping and gaping perforations. Successful closure resulted in a leakproof sealing at 2 weeks and prevented clinical peritonitis in all the animals in the clip-closure group and in 3 of 4 animals in the suture-closure group. Necropsy at 2 weeks revealed mild peritonitis in 2 of the 5 animals in the clip closure group and in 2 of the 4 animals in the suture-closure group; none developed fecal peritonitis.

LIMITATIONS

None.

CONCLUSIONS

Endoluminal closure of a 4-cm colon perforation with clips was successful in the majority of cases. Sutures were useful in the closure of gaping colon perforations that could not be closed with clips.

Colonoscopic perforations: a review of 30,366 patients

BACKGROUND

Although the incidence of perforation after endoscopic procedures of the colon is low, the rising number of procedures could pose relevant health problems. Recognizing risk factors and optimizing treatment may reduce perforation incidence and the probability of (severe) complications. This study aimed to determine perforation frequency and the management of endoscopic colonoscopic perforation.

METHODS

A retrospective review of patient records was performed for all patients with iatrogenic colonic perforations after sigmoido/colonoscopy between 1990 and 2005. The patients' demographic data, endoscopic procedural information, perforation location, therapy, and outcome were recorded.

RESULTS

In the 16-year period, 30,366 endoscopic colonic procedures were performed. In total, 35 colonic perforations occured (0.12%). All the patients underwent a laparotomy: for primary repair in 18 cases (56%), for resection with anastomosis in 8 cases (25%), and for resection without anastomosis in 6 cases (19%). In three patients (8.6%), no perforation was found. The postoperative course was uncomplicated in 21 cases (60%) and complicated in 14 cases (40%), including mortality for 3 patients (8.6% resulting from perforations and 0.01% resulting from total endoscopic colon procedures). The relative risk ratio of colonoscopic and sigmoidoscopic procedures for perforations was 4. Therapeutic procedures show a delay in presentation and diagnosis compared with diagnostic procedures. Of the 35 perforations, 26 (74%) occurred in the sigmoid colon.

CONCLUSION

Iatrogenic colonic perforation is a serious but rare complication of colonoscopy. A perforation risk of 0.12% was found. The perforation risk was higher for colonoscopic procedures than for sigmoidoscopic procedures. The sigmoid colon is the area at greatest risk for perforation. Immediate operative management, preferably primary repair and sometimes resection, appears to be a good strategy for most patients.

Racial disparities in colon cancer. Primary care endoscopy as a tool to increase screening rates among minority patients

Colon cancer is a condition whose far-reaching effects have been well documented nationally and within the state of South Carolina. Fortunately, the disease is amenable to both primary and secondary prevention through screening colonoscopy. Despite the conceptual simplicity of recommending colonoscopy, barriers exist to universal (or even widespread) screening. Currently the infrastructure necessary to achieve screening goals set by the American Cancer Society (ACS), the American College of Gastroenterology (ACG), and the South Carolina Department of Health and Environmental Control (DHEC) has not been established. At current rates of training gastroenterologists, the medical community will not be able to come close to achieving widespread screening. Given the discrepancy between the public health benefit of achieving the goals and the deaths that have occurred because of the resource shortfall, we propose alternative measures to screen the at-risk population for consideration. This need is most acute in the black community, in which where screening rates tend to be lower and polyps have been found to progress more quickly than among white populations. In South Carolina, one model has used primary care physicians as the labor force to provide routine screening colonoscopy for their own patients. This model makes screening much more accessible to minority patients, as the wait is shorter and the cost typically lower. In combination with a faith-based partnership with minority religious organizations, this model has begun to make needed inroads toward addressing the disparities associated with colon cancer. Cancer 2007. (c) 2006 American Cancer Society.

Conventional colonoscopy: Technique, indications, limits

Colonoscopy has long been the gold standard for the diagnosis of colonic diseases. Recently, with the advent of CT colonografy, new alternatives seem to appear on the horizon, which seem to finally overcome some of colonoscopy's drawbacks like procedure related pain and discomfort during the examination. Polyp miss rate and the fact that not always the caecum can be reached are also the basis of debate. This article gives an overview about current technique, indications and limitations of diagnostic colonoscopy as well as a potential prospect for the future, discussing novel imaging technologies ranging from magnification endoscopy to virtual histopathology.

Stick, unstick, restick sticky films in the colon

The main challenge in designing diagnostic devices able to move along the colon is their locomotion method. Manipulating friction with the colonic surface is a key requirement for their safe and atraumatic propagation. One possible solution is to generate friction by means of adhesive forces. For this reason, a diagnostic device can be covered with mucoadhesive films that are able to stick on the colonic surface by generating high static friction. For a smooth transition from static to dynamic regime, the mucoadhesive films should unstick just before the initialisation of motion. Experiments have shown that promoting cohesive fracture of the films by controllable air introduction does not lead to friction reduction sufficient for smooth unsticking. Introducing water at the film-colon interface, however, reduces the static friction significantly, and makes the device to unstick and slide smoothly without leaving film fragments on the colonic surface behind. If unsticking is initiated by means of air or water introduction, a new film is required each time the device is required to restick. As an alternative, the possibility of coating the device with environmentally-sensitive mucoadhesive polymers that can respond reversibly to external stimuli and alter their properties is discussed.

The management of small polyps found by virtual colonoscopy: results of a decision analysis

BACKGROUND & AIMS

There is a firm consensus that larger (> or =10 mm) colonic polyps should be removed; however, the importance of removing smaller polyps (<10 mm) is more controversial. If computed tomographic colonography (CTC) is used for colorectal cancer screening, the majority of polypoid lesions identified will be less than 10 mm in size. Decision-analytic techniques were used to compare the outcomes of 2 management strategies for smaller (6-9 mm) polyps discovered by CTC.

METHODS

Hypothetic average-risk patients who had undergone a CTC examination and found to have a small (6-9 mm) polyp were simulated to either: (1) undergo immediate colonoscopy for polypectomy (COLO), or (2) wait 3 years for a repeat CTC examination (WAIT). A Markov model was constructed to analyze outcomes including the number of deaths and cancers after a 3-year follow-up period or time horizon. Values for the model parameters were derived from the published literature and from Surveillance Epidemiology and End Results data, and an extensive sensitivity analysis was performed.

RESULTS

The COLO strategy resulted in 14 total deaths per 100,000 patients compared with 79 total deaths in the WAIT strategy, for a difference of 65 deaths. The COLO strategy resulted in 39 cancers per 100,000 patients vs 773 in the WAIT strategy, for a difference of 734 cancers. Sensitivity analysis found that model findings were robust and only sensitive at extreme parameter values.

CONCLUSIONS

Managing smaller polyps detected on a screening CTC with another CTC examination 3 years later likely will result in more deaths and cancers than immediate colonoscopy and polypectomy.

Colorectal cancer screening: results of a 5-year program in asymptomatic subjects at increased risk

BACKGROUND AND AIMS

The province of Ferrara has one of the highest incidences of colorectal cancer (CRC) in Italy. In January 2000, we set up a colonoscopy screening program focussing on first-degree relatives of CRC patients. We now report the results 5 years after the beginning of the project. SCREENEES AND METHODS: In October 1999, we started a campaign stressing the usefulness of colonoscopy for the first-degree relatives of CRC patients. Subjects included in the screening program were aged between 45 and 75 years with at least one first-degree relative affected by CRC. They were invited to an interview where a physician suggested colonoscopy as a screening option.

RESULTS

In 5 years, 776 subjects were interviewed and 733 (94.4%) agreed to an endoscopic examination (M/F:375/401; mean age 55 years): 562 colonoscopies were performed. Adenomas and cancers were found in 122 (21.7%) and 12 (2.1%) subjects, respectively. Histological examination in 181 persons with lesions (32.8%) showed (most serious lesion quoted) 47 hyperplastic polyps (26% of all lesions), 2 serrated adenomas (1.1%), 68 tubular adenomas (48%), 24 tubulovillous adenomas (13.3%), 9 adenomas with high grade dysplasia (5%) and 12 adenocarcinomas (6.6%). The majority of the cancers were at an early stage (8 Dukes A and 3 Dukes B). Sedation was used in only 42 colonoscopies (7.5%).

CONCLUSIONS

A colonoscopy-based screening in this selected high-risk population is feasible. Even without sedation subjects readily agreed to the endoscopic procedure. We identified a significant number of advanced neoplasms and cancers at an early stage suggesting that this could be a useful tool in early identification of CRC.

Colorectal cancer screening

Colorectal cancer is a major public health burden worldwide. There is clear-cut evidence that screening will reduce colorectal cancer mortality and the only contentious issue is which screening tool to use. Most evidence points towards screening with fecal occult blood testing. The immunochemical fecal occult blood tests have a higher sensitivity than the guaiac-based tests. In addition, their automation and haemoglobin quantification allows a threshold for colonoscopy to be selected that can be accommodated within individual health care systems.

Colonoscopy completion and complication rates in a community gastroenterology practice

BACKGROUND

In the United States, colonoscopy completion and complication rates are rarely reported outside academic institutions. Increased transparency of quality measures and outcomes is being driven by professional societies, government agencies, and private enterprise.

OBJECTIVE

To collect and report the completion and complication rates of colonoscopy in a community gastroenterology practice.

DESIGN

Single-center study, prospective for completion, retrospective for complications.

SETTING

Community gastroenterology group practice, conducted from August 2002 through December 2004.

PATIENTS

A total of 12,407 consecutive patients referred for colonoscopy; mean age, 59.7 years; 5925 men.

INTERVENTIONS

Polypectomy and cautery were completed as indicated.

MAIN OUTCOME MEASURES

Completion of colonoscopy to cecum or ileocolonic anastomosis. Complications of hemorrhage and perforation.

RESULTS

A colonoscopy was completed in 98.4% of patients. Polypectomy was accomplished in 5074 (40.9%). Polyps occurred more often in men (46.4% vs 35.8%, P < .001). Causes for failure included difficult anatomy (55.9%), inadequate preparation (20.8%), obstructing malignancy (8.6%), discomfort (8.1%), and severe inflammation (6.1%). Failure from difficult anatomy was more likely in women (1.19% vs 0.56%, P < .001). Hemorrhage requiring hospitalization occurred after 25 cases (0.20%). Twenty-three episodes of bleeding occurred after polypectomy (0.46%) and 2 after treatment of arteriovenous malformations. Two perforations occurred (0.016%). One patient developed a posterior circulation stroke. No deaths occurred.

LIMITATIONS

Completion not independently verifiable. Complications were collected retrospectively.

CONCLUSIONS

Colonoscopy completion and complication rates in this community gastroenterology practice compared favorably with U.S. academic centers. Endoscopic quality in community practices can meet published outcomes.

Complications of Abdominal and Pelvic Procedures: Computed Tomographic Diagnosis

The postprocedural period is a critical time in which serious complications can manifest. Localization of suspected complications following abdominal and pelvic procedures can be difficult on clinical evaluation alone. For example, abdominal pain after a colonoscopy may vary in etiology and can result from simple colonic spasm to colonic perforation, hemoperitoneum, or even splenic rupture. Vague abdominal pain following a renal biopsy may be due to minimal postprocedural bleeding into and around the kidney or may be due to potentially life-threatening hemorrhage. In such patients, computed tomography can play a crucial role in the rapid identification of complications as well guidance of subsequent patient management. The purpose of this article is to demonstrate the benefit of computed tomography-assisted diagnosis of complications associated with routine procedures performed on or throughout the abdomen and pelvis, including cardiac catheterization, colonoscopy, endoscopy, percutaneous biopsy, and interventional radiology procedures.

Incidence and management of colonoscopic perforations: 8 years' experience

AIM

To review the experience of a major medical teaching center with diagnostic and therapeutic colonoscopies and to assess the incidence and management of related colonic perforations.

METHODS

All colonoscopies performed between January 1994 and December 2001 were studied. Data on patients, colonoscopic reports and procedure-related complications were collected from the departmental computerized database. The medical records of the patients with post procedural colonic perforation were reviewed.

RESULTS

A total of 120067 colonoscopies were performed during the 8 years of the study. Seven colonoscopic perforations (4 females, 3 males) were diagnosed (0.058%). Five occurred during diagnostic and two during therapeutic colonoscopy. Six were suspected during or immediately after colonoscopy. All except one had signs of diffuse tenderness and underwent immediate operation with primary repair done in 4 patients. No deaths were reported.

CONCLUSION

Perforation rate during colonoscopy is low. Nevertheless, it is a serious complication and its early recognition and treatment are essential to optimize outcome. In patients with diffuse peritonitis early operative intervention makes primary repair a safe option.

Intraoperative sigmoidoscopy in gynecologic surgery

Intraoperative sigmoidoscopy is underused by the majority of practicing gynecologists and is not widely taught in obstetrics and gynecology training programs. In this report, a step-by-step approach is provided in order to perform sigmoidoscopy. Indications for use, along with various intraoperative applications, are discussed. Results from our center's experience with its use during laparoscopic treatment of adhesions, endometriosis, and associated disease of the bowel also are provided. Intraoperative sigmoidoscopy is a safe and efficacious procedure that can aid in the evaluation and treatment of pelvic pathology and facilitate identification and management of bowel injuries. It should be considered a valuable adjunct when such cases are encountered by gynecologic and pelvic surgeons.

Laparoscopic treatment of endoscopic sigmoid colon perforation: a case report and literature review

Perforation of the colon after colonoscopy is a rare but potentially lethal complication. It usually occurs when endoscopy is performed for therapeutic purposes. In these cases the election of the best treatment is difficult and still controversial. Laparoscopy is a new approach for diagnosis and treatment of this condition. We report a case of a patient who was initially treated laparoscopically after a colonoscopic perforation. A postoperative leak was detected and the patient underwent open surgery. Possible therapeutic approaches and a literature review are discussed.

Perforation of the colon and rectum--a newly recognized complication of CT colonography

CT colonography (CTC) and conventional colonoscopy may have similar efficacy for detection of polyps > 6 mm. Perforation of the colon and rectum is a relatively rare, but potentially morbid complication of CTC, especially in symptomatic patients. Older age and underlying concomitant colon pathology increase the risk of perforation. This review describes the incidence, clinical features, and management of colon perforations at CTC, a study that was considered risk-free until recently.

Effective screening for bowel cancer: a United kingdom perspective

Bowel cancer is a major cause of morbidity and death and is a high cost to health care systems. Screening currently offers the best chance of improving outcomes from bowel cancer. When introducing screening, the problems encountered in other cancers need to be avoided to maximize benefits and minimize harms.

Colonic Irrigations: A Review of the Historical Controversy and the Potential for Adverse Effects

Colonic irrigations enjoy widespread popularity among alternative medicine practitioners, although they are viewed with considerable skepticism by the conventional medical community. Although proponents make claims of substantial health benefits, skeptics cite the lack of evidence for health benefits and emphasize the potential for adverse effects. Yet historically, there are clinical reports of effectiveness and virtually no research refuting these reports. Instead there was a campaign against exaggerated claims by nonmedical practitioners that resulted in a movement away from this form of therapy without any scientific study of efficacy. Given the current popularity of colonic irrigations, it is important that such research be performed, which will require a quantitative estimate of the potential for adverse effects. Although there is little specific literature on colonic irrigations, a review of the literature on related procedures such as enemas and sigmoidoscopies suggests that the risk of serious adverse effects is very low when the irrigations are performed by trained personnel using appropriate equipment.

Emphysème sous-cutané, pneumomédiastin, pneumopéritoine et rétropneumopéritoine dans les suites d’une coloscopie avec mucosectomie

The occurrence of associated intraperitoneal and retroperitoneal colonic perforation is uncommon after colonoscopy. We report a case of this complication revealed by subcutaneous emphysema, pneumomediastinum, pneumoperitoneum and retro-pneumoperitoneum after colonic mucosectomy.

Colon pathology detected after a positive screening flexible sigmoidoscopy: a prospective study in an ethnically diverse cohort

OBJECTIVES

Although the association between distal neoplasia on sigmoidoscopy and proximal colonic pathology on follow-up colonoscopy has been well-described, it is not known if these findings are consistent across ethnic groups. The aim of this study was to evaluate ethnic variations in the prevalence of proximal neoplasia on follow-up colonoscopy after a neoplastic lesion is found on sigmoidoscopy.

METHODS

Consecutive asymptomatic patients at average-risk for colorectal cancer who were referred for screening flexible sigmoidoscopy were prospectively enrolled. Colonoscopy was recommended for all patients with a polyp on flexible sigmoidoscopy, regardless of size. Advanced neoplasms were defined as adenomas > or = 10 mm in diameter or any adenoma, regardless of size, with villous histology, high-grade dysplasia, or cancer.

RESULTS

Among the 2,207 patients who had sigmoidoscopy, 970 were Caucasian, 765 were African American, 395 were Hispanic, and 77 were Asian. The prevalence of neoplasia in the distal colon was 12.6% in Caucasians, 11.2% in African Americans, 15.9% in Hispanics, and 24.7% in Asians (p = 0.002). Of the 290 patients with neoplastic lesions on sigmoidoscopy, follow-up colonoscopy identified neoplasms in the proximal colon in 63.9% of Caucasians, 59.3% of African Americans, 66.7% of Hispanics, and 26.3% of Asians (p = 0.01). Advanced neoplasms in the proximal colon were highest in African Americans (34.9%) and lowest in Asians (10.5%).

CONCLUSIONS

In our study population, Asians demonstrated a higher prevalence of distal colonic neoplasia and a lower prevalence of proximal colonic neoplasia compared to non-Asians. Future studies should explore ethnic variation in colonic neoplasia prevalence and location since ethnic variation could lead to tailored colorectal cancer screening strategies.

Colonic perforation at CT colonography: assessment of risk in a multicenter large cohort

PURPOSE

To assess retrospectively the incidence, clinical features, and treatment of colonic perforation at computed tomographic (CT) colonography in a large multicenter cohort.

MATERIALS AND METHODS

The study was performed in accordance with the institutional ethics committees' requirements of a retrospective review in each of the participating centers, and no informed consent was required. A review of all patients who underwent CT colonography between January 2001 and December 2004 in 11 medical centers representing more than 95% of studies performed in a single country was performed to determine the rate of colorectal perforation. Data about patient demographics and patient- and procedure-related risk were recorded. Information about the location of the perforation, its likely mechanism, and treatment was collected. Analysis included calculation of rates of colonic perforation and surgical treatment and of 95% confidence intervals.

RESULTS

A total of 11 870 CT colonographic studies were performed in 6837 (57.6%) men and 5033 (42.4%) women (mean age, 59.9 years; range, 38-90 years) with seven cases of colorectal perforation, yielding a risk rate of 0.059% (one of 1696 studies; 95% confidence interval: one of 974, 971 of 6537). The mean age of the patients with perforation was 77.8 years. Six (84%) of seven cases of perforation occurred in symptomatic patients at high risk for colorectal neoplasia, and one (16%) occurred in an asymptomatic average-risk patient. All studies were performed after insufflation of room air. Six (84%) cases of perforation occurred in patients in whom a rectal tube was inserted, and in five of them, a balloon was inflated. Five (71%) cases of perforation occurred in the sigmoid colon; and two (29%), in the rectum. Four (57%) patients (one in 2968 patients; 95% confidence interval: 1.5 in 10 000, 14.7 in 10 000) required surgical treatment. Possible factors that contributed to perforation were left inguinal hernia containing colon (n = 4), severe diverticulosis (n = 3), and obstructive carcinoma (n = 1).

CONCLUSION

Perforation of the colon and rectum is a rare complication of CT colonography. Older age and underlying concomitant colonic disease were present in patients with perforation.

Rectal perforations after barium enema: a review

PURPOSE

Rectal injuries during barium enema are rare but life-threatening complications. The last review about this subject was published more than ten years ago. In the present review, we present an overview on the subject and especially focus on changes in treatment strategies and developments of less risky visualization techniques.

METHODS

A literature search was performed in the PubMed library using the key words-barium enema, complications, peritonitis, and rectal perforation-as well as related articles and other references obtained from these articles.

RESULTS

The most frequent cause of perforation is iatrogenic and catheter-related. Other causes are related to weakness of the colorectal wall or obstruction. Five types of perforations have been described: 1) perforations of the anal canal below the levator; 2) incomplete perforations; 3) perforations into the retroperitoneum; 4) transmural perforations into adjacent viscera; 5) perforations into the free intraperitoneal cavity. Most incomplete perforations and one-half of the retroperitoneal perforations have minimal clinical signs. Intraperitoneal perforations lead to the most catastrophic course, starting with rectal bleeding and mild abdominal complaints. This is rapidly followed by progressive sepsis and peritonitis, and leads to a high mortality rate. Surgery is not always required for intramural or small retroperitoneal perforations. These can be treated conservatively and require surgical debridement only in case of large amounts of extravasation or abscesses. Surgical repair of large rectal mucosal lesions or anal sphincter lesions is advised. Perirectal abscesses require drainage. Intraperitoneal perforations with gross extravasation need immediate aggressive surgical treatment in a critical care setting, because the threat of shock is high. Intraperitoneal perforations, neglected perforations, gross barium extravasation, poorly prepared colon, and venous intravasation of barium are prognostically unfavorable. The severest late complication in intraperitoneal perforations is ileus. Meticulous technical performance of the barium enema is the most important factor in prevention.

CONCLUSIONS

Rectal perforations after barium enema are rare. The overall mortality rate decreased in recent decades from approximately 50 to 35 percent as the result of advances in supportive and intensive care. Because of these advances, more aggressive surgical strategies were undertaken. With the advent of endoscopy, less barium enemas are performed. Consequently, the absolute incidence of complications has decreased. It is expected that in the future barium enemas will be replaced by more sensitive and less risky techniques, such as CT colonography and magnetic resonance colonography.

Endoscopic therapy of lower gastrointestinal cancer

Since the 1960's, endoscopy has revolutionised the practice of gastroenterology. Although initially diagnostic, endoscopy is now playing an increasingly therapeutic role. There are many reasons to believe that therapeutic endoscopy will shape the practice of gastroenterology further in the future. Only a few years ago we relied on low-resolution fibreoptic endoscopes. Nowadays even standard equipment allows the mucosa to be scrutinised in great detail. Dedicated training in endoscopy together with attention to quality indicators such as polyp detection and caecal intubation rates will ensure that fewer early gastrointestinal cancers are missed in the future. Open access endoscopy and screening programs are being introduced in many Western countries which will also lead to more lesions being detected in their early stages. This chapter discusses the main issues surrounding the endoscopic therapy of lower gastrointestinal cancers.

Colonoscopic perforations: a retrospective review

Colonic perforation is no longer a rare complication of colonoscopy. Our previous report identified 45 such iatrogenic injuries from 1980 through 1994 (3082 colonoscopies per year). This follow-up of the ensuing 7 years examines changing trends of endoscopic usage in addition to management and prognosis of patients with colonoscopic perforations. Retrospective analysis of 78,702 colonoscopies (1994 through 2000, 11,243 colonoscopies per year) allowed assessment of medical records in all patients treated at our institution for colonic perforation. Sixty-six patients from our institution (perforation rate, 0.084%; 1 per 1192 procedures) and six patients from outside institutions were treated for colonic perforation following colonoscopy (41 women, 31 men; ages, 30-92 years; median, 73 years). Sixty-two patients underwent laparotomy, while 10 were managed nonoperatively. All 10 patients managed nonoperatively were void of peritoneal irritation by physical examination; eight patients did well (median hospital stay, 5.5 days; range, 0-12), but one death (family declined operative intervention) and one pelvic abscess requiring percutaneous drainage were noted. Peritoneal irritation by physical examination was evident in 57 of 62 patients undergoing laparotomy. Perforations occurred throughout the colon: right, 22 (31%); transverse, 5 (7%); left, 44 (61%); and unknown, 1 (1%). Thirty-eight patients (61%) underwent primary repair or resection with anastomosis. Fecal diversion was used in 100% of patients with extensive peritoneal contamination (n = 12) and 40% of patients with moderate contamination (12 of 30). Perioperative morbidity (39%) and mortality (8%) were significant. Factors predicting a poor outcome included delayed diagnosis, extensive peritoneal contamination, and patients using anticoagulants (P < .05). Compared with our prior study, the present review highlights a higher prevalence of injury based on more frequent use of colonoscopy. Perforation rates remain around 0.08%. While nonoperative management is viable in patients void of peritonitis, expedient surgical intervention seems to facilitate patient recovery.

MRI in Crohn's disease

Technological developments have extended the role of MRI in the evaluation of the gastrointestinal tract. The potential of MRI to evaluate disease activity in Crohn's disease has been investigated extensively, as MRI has intrinsic advantages over other techniques, including noninvasiveness and the absence of ionizing radiation. For perianal fistulizing disease MRI has become a mainstay in evaluation of disease, as localization and extent of disease can be very well appreciated using both T2-weighted and T1-weighted sequences, fat suppression, and intravenous contrast medium. Imaging of the small bowel and colon in Crohn's disease is more complicated due to bowel peristalsis and respiratory movement. However, using fast breathhold sequences and intravenous spasmolytic medication, images of good diagnostic quality can be acquired. To obtain sufficiently distended bowel, which in our estimation is a prerequisite for evaluation of the bowel, MR enteroclysis can be performed. However, applicability of different oral contrast media has been studied, as a noninvasive method for bowel distension would be preferable. Abdominal MRI is a valuable imaging technique for evaluation of luminal, transmural, and extraintestinal manifestations of Crohn's disease as degree of disease activity, presence of luminal pathology (e.g., stenoses), and extraintestinal manifestations of disease (e.g., abscesses, fistulas) can be accurately assessed.

Colon polyp retrieval after cold snaring

BACKGROUND

The removal of small colon polyps by cold snare transection without electrocautery effectively eliminates polyps, and anecdotal reports indicate a low risk of bleeding and perforation. Concerns about using cold snaring have centered on the risk of immediate bleeding and the difficulty in retrieving the polyp. The objective was to determine the retrieval rates of polyps after cold snaring after two different methods of resection and retrieval.

METHODS

Consecutive polyps were identified by a single colonoscopist who chose the technique of polypectomy (hot snare, cold snare, or cold forceps). If cold snaring was chosen, an independent observer assigned the polyp to method A (cold resection of polyp without tenting and then suction of the transected polyp into a trap) or method B (ensnare the polyp, pull it into the colonoscope channel, and then transect it while suctioning). The size and the approximate location of all polyps were recorded and all collected specimens were sent separately for histologic examination. Results Of 519 consecutively encountered polyps, 400 were removed by cold snare: 197 were assigned to method A and 203 to method B. The mean size of polyps that were cold snared was 3.5 mm. The mean time to remove and to retrieve polyps with method A was 14.5 seconds (n = 58) and with method B was 18.1 seconds (n = 60) ( p = 0.03). There were no complications from cold snaring. The rate of successful retrieval with method A was 100% (197 of 197 polyps) and with method B was 98% (199 of 203 polyps) ( p = 0.04).

CONCLUSIONS

Cold snare removal of colon polyps is associated with a high polyp retrieval rate. Each of two methods of polyp retrieval was effective. Snare transection without tenting of the polyp, followed by suctioning of the specimen off the polyp site, was more efficient, though the difference in efficiency was minimal. Difficulty or failure to retrieve polyps should not be a concern with regard to cold snare polypectomy.

Mucoadhesives in the gastrointestinal tract: revisiting the literature for novel applications

This article investigates applying mucoadhesives to manipulate friction and to achieve locomotion of an alternative colonoscopic device through the large intestine. Considering that such an application of mucoadhesives is new, the authors recognised the need to revisit the different aspects of mucoadhesion in the gastrointestinal tract on the basis of the literature and to re-evaluate them according to the requirements for intestinal locomotion. First, the material properties, which are critical for the locomotion mechanism and specific categories of mucoadhesives characterised by those critical properties were identified. The next step was to examine the structural characteristics of those categories to specify which of the already synthesised mucoadhesives are promising candidates for friction manipulation. Then, the response of those mucoadhesives to a number of environmental stimuli was examined. At the end, two in vitro experiments were carried out to study the potential of mucoadhesives for intestinal locomotion. A comparative analysis of the role of mucoadhesives in drug delivery and in intestinal locomotion leads to the conclusion that the two applications can be approached to one extent with common principles, but crucial differences are present as well.

Feasible economic strategies to improve screening compliance for colorectal cancer in Korea

AIM: While colorectal cancer (CRC) is an ideal target for population screening, physician and patient attitudes contribute to low levels of screening uptake. This study was carried out to find feasible economic strategies to improve the CRC screening compliance in Korea.

METHODS: The natural history of a simulated cohort of 50-year-old Korean in the general population was modeled with CRC screening until the age of 80 years. Cases of positive results were worked up with colonoscopy. After polypectomy, colonoscopy was repeated every 3 years. Baseline screening compliance without insurance coverage by the national health insurance (NHI) was assumed to be 30%. If NHI covered the CRC screening or the reimbursement of screening to physicians increased, the compliance was assumed to increase. We evaluated 16 different CRC screening strategies based on Markov model.

RESULTS: When the NHI did not cover the screening and compliance was 30%, non-dominated strategies were colonoscopy every 5 years (COL5) and colonoscopy every 3 years (COL3). In all scenarios of various compliance rates with raised coverage of the NHI and increased reimbursement of colonoscopy, COL10, COL5 and COL3 were non-dominated strategies, and COL10 had lower or minimal incremental medical cost and financial burden on the NHI than the strategy of no screening. These results were stable with sensitivity analyses.

CONCLUSION: Economic strategies for promoting screening compliance can be accompanied by expanding insurance coverage by the NHI and by increasing reimbursement for CRC screening to providers. COL10 was a cost-effective and cost saving screening strategy for CRC in Korea.

Screening of patients at average risk for colon cancer

Both the incidence and the mortality from colorectal cancer can be substantially reduced by primary and secondary prevention. There are many screening tests for colorectal cancer, and any test should result in a reduction in colorectal cancer incidence and mortality. If the age-eligible population undergoes these screening tests, the burden of colorectal cancer should be substantially reduced. The scientific evidence related to secondary prevention, specifically screening of individuals at average risk for colorectal cancer, is presently reviewed.

Safety and efficacy of colonoscopy after myocardial infarction: an analysis of 100 study patients and 100 control patients at two tertiary cardiac referral hospitals

BACKGROUND

The purpose of this study is to analyze the risks vs. the benefits of colonoscopy soon after myocardial infarction.

METHODS

A total of 100 consecutive patients undergoing colonoscopy within 30 days after myocardial infarction at two large tertiary cardiac referral hospitals were studied. The study group was compared with 100 control patients with neither myocardial infarction nor unstable angina during the preceding 6 months (matched for age, colonoscopy indication, and colonoscopist) who underwent colonoscopy.

RESULTS

Indications for colonoscopy were bleeding per rectum (37 patients), fecal occult blood (36 patients, hematocrit < 30% in 25), iron deficiency anemia (11 patients, hematocrit < 25% in 9), and other (16 patients). Colonoscopy was performed at a mean of 15.5 (8.3) days after myocardial infarction. Two patients underwent colonoscopic colonic decompression. Colonoscopy was diagnostic in 46 (47%) of the study patients vs. 41% of the control patients ( p = 0.47, chi-square test). The relative rate of ischemic colitis was significantly higher in study vs. control patients (14 vs. 2, p < 0.005). Other diagnoses in study patients were the following: colon cancer (8), bleeding internal hemorrhoids (5), pseudomembranous colitis (5), high-risk adenomatous polyp (large or villous histopathology) (4), and other (10). Urgent colonoscopy was diagnostic in 63% of cases. Twenty-three patients had a major therapeutic benefit consequent to colonoscopy, including colon cancer surgery in 5. Study patients were significantly sicker than control patients (APACHE II score 9.9 [4.3] vs. 7.4 [2.8], p < 0.0001) and suffered significantly more colonoscopic complications compared with control patients (9 vs. 1; OR 5.2: 95% CI [1.2, 9.8], p < 0.03). Minor complications without clinical sequelae occurred in 8 study patients (asymptomatic hypotension or bradycardia). One major complication occurred in this group that was probably not procedure related.

CONCLUSIONS

Colonoscopy in patients with a recent myocardial infarction is associated with a higher rate of minor, transient, and primarily cardiovascular complications compared with control patients but is relatively infrequently associated with major complications. Colonoscopy is beneficial and indicated after myocardial infarction, despite a higher risk, in certain circumstances. The relative frequency of ischemic colitis was relatively high in study patients.

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Assessment of outcomes after colorectal cancer resection in the elderly as a rationale for screening and early detection

BACKGROUND

Clinical, social and survival outcomes in elderly patients undergoing bowel cancer surgery were studied to explore the justification for the current upper age limit in colorectal cancer screening programmes.

METHODS

Scottish national data were analysed to determine age-specific population survival following a diagnosis of colorectal cancer. Detailed analysis of outcome variables was undertaken in a cohort of 180 patients aged over 80 years who underwent resection of colorectal cancer.

RESULTS

Population analysis revealed that the absolute risk of developing colorectal cancer was highest in those aged over 80 years, but relative survival was disproportionately poor. Of 180 patients in this age group, 30.0 per cent required an emergency procedure and only 4.6 per cent had Dukes' stage A tumours. Determinants of all-cause mortality were tumour stage (P < 0.001) and degree of co-morbidity (P = 0.004). Some 88.0 per cent of elderly patients returned to the same category of accommodation as that before admission.

CONCLUSION

Colorectal cancer is increasingly common in people aged over 80 years and survival is disproportionately poor compared with that in other age groups. Elective management of early-stage cancer has a better outcome than emergency surgery. The majority of patients maintain social independence. These population and hospital data provide a rationale for early, and even presymptomatic, detection of colorectal cancer in the elderly.

A national survey of flexible sigmoidoscopy training in primary care graduate and postgraduate education programs

OBJECTIVES

Expanding the pool of primary care endoscopists to perform flexible sigmoidoscopy (FS) has been advocated as a strategy for building colorectal cancer screening capacity. The principal aim of this study was to evaluate the availability and structure of FS training among internal medicine (IM), family practice (FP), physician assistant (PA), and nurse practitioner (NP) training programs.

METHODS

A postal survey of all accredited IM (n = 445), FP (n = 471), PA (n = 118), and NP (n = 149) training programs nationwide was conducted. The primary outcome was the proportion of programs offering or mandating FS training; and secondary outcomes, if applicable, were the number of participating trainees, the number of required procedures, the availability of instruction in endoscopic biopsy technique, mentors, and barriers.

RESULTS

The overall response rate was 63%. Most IM (89%) and FP (99%) programs offered FS training versus only 12% of PA and 0% of NP programs. Family practice programs were more likely to offer training (p < 0.0001), require training (p < 0.0001), and teach biopsy techniques (p < 0.0001); Internal medicine programs were more likely to have minimum requirements (p < 0.0001) and required >/= 25 procedures per trainee (p < 0.0001). Physician assistant programs were less structured and often lacked minimum requirements.

CONCLUSIONS

Flexible sigmoidoscopy training is widely available among FP and IM programs but more restricted or nonexistent among PA and NP programs. The lack of minimum standards for ensuring competency highlights the need for a standardized credentialing process.

Risk management regarding sedation/analgesia

Because the definition of standard of care changes with time, it is difficult to predict whether any given technique or practice will be ultimately viewed as the next advance in care or will be discarded as unnecessary or cumbersome. It is too early to tell whether deep sedation/analgesia with propofol or some other ultrashort acting anesthetic will emerge as the sedative/analgesic of choice for routine endoscopic practice. It seems that deep sedation with propofol provides some advantages over current narcotic/benzodiazepine combinations in many circumstances, but potential risks exist. Further information, including careful documentation of the complications that occur with this and similar agents, be they attributable to the drug or the level of sedation, are eagerly awaited. For now, it seems prudent to continue to recommend that the level of sedation/analgesia be appropriate to the perceived need and that patients continue to have their procedures performed with safety, comfort, and competence as the overriding concerns.