Complications and hazards of gastrointestinal endoscopy

The impact on clinical outcomes and healthcare resources from discontinuing colonoscopy surveillance subsequent to low-risk adenoma removal: A simulation study using the OncoSim-Colorectal model

OBJECTIVE

To estimate the impact on clinical outcomes and healthcare resource use from recommending that patients with 1-2 low-risk adenomas (LRAs) return to routine fecal immunochemical test (FIT) screening instead of surveillance colonoscopy, from a Canadian provincial healthcare system perspective.

METHODS

The OncoSim-Colorectal microsimulation model simulated average-risk individuals eligible for FIT-based colorectal cancer (CRC) screening in Alberta, Canada. We simulated two surveillance strategies that applied to individuals with 1-2 LRAs (<10 mm) removed as part of the average risk CRC screening program: (a) Surveillance colonoscopy (status quo) and (b) return to FIT screening (new strategy); both at 5 years after polypectomy. A 75 ng/mL FIT positivity threshold was used in the base case. The simulations projected average annual CRC outcomes and healthcare resource use from 2023 to 2042. We conducted alternative scenarios and sensitivity analyses on key variables.

RESULTS

Returning to FIT screening (versus surveillance colonoscopy) after polypectomy was projected to have minimal impact on long-term CRC incidence and deaths (not statistically significant). There was a projected decrease of one (4%) major bleeding event and seven (5%) perforation events per year. There was a projected increase of 4800 (1.5%) FIT screens, decrease of 3900 (5.1%) colonoscopies, and a decrease of $3.4 million (1.2%) in total healthcare costs per year, on average. The annual colonoscopies averted and healthcare cost savings increased over time. Results were similar in the alternative scenarios and sensitivity analyses.

CONCLUSIONS

Returning to FIT screening would have similar clinical outcomes as surveillance colonoscopy but could reduce colonoscopy demand and healthcare costs.

Management of scope-induced type I duodenal perforations: Over-the-scope clip versus surgery

BACKGROUND

Scope-induced duodenal perforation is a life-threatening complication and surgery remains the standard of care. With the advent of over-the-scope clip (OTSC), scope-induced perforations are increasingly managed conservatively, though there is no study comparing this form of non-surgical treatment with surgery. We aimed to compare OTSC and surgery in the management of scope-induced perforation of the duodenum.

METHODS

We retrospectively collected data of scope-induced duodenal perforation patients. Perforations identified and treated within 24 h of procedure were analyzed. Factors analyzed were spectrum, etiology, baseline parameters, perforation size, outcome, comorbidities, and duration of hospital stay.

RESULTS

A total of 25 patients had type I duodenal perforations, out of whom five were excluded due to delayed diagnosis and treatment. Of the twenty, eight were treated with OTSC placement while the rest underwent surgery. Age was comparable and the majority were females. Baseline parameters and comorbidities were similar in both the groups. The median size of perforation was 1.5 cm in both the OTSC group and the surgical group. All patients were treated with standard of care according to institutional protocols. Patients in the OTSC group were started orally after 48 h of OTSC placement, while in the surgery group median time to oral intake was 7 days. Two patients in the surgical group died while there was no mortality in the OTSC group (p = 0.48). Median hospital stay was shorter in the OTSC group (2 days vs. 22 days, p = 0.003).

CONCLUSIONS

OTSC is a feasible and better option in type I duodenal perforations with a shorter hospital stay.

A national survey on esophageal perforation: study of cases at accredited institutions by the Japanese Esophagus Society

OBJECTIVE

To get a clear view of the current state of treatment for esophageal perforation in Japan. Esophagus perforations are the most serious gastrointestinal tract perforations and are associated with high morbidity and mortality. The optimal treatment choice remains unknown.

METHODS

We conducted a retrospective clinical review of 182 esophageal perforation cases at 108 hospitals accredited by the Japanese Esophageal Society between January 2010 and December 2015.

RESULTS

We found that 20.9% of patients were incorrectly diagnosed initially. We observed mediastinum emphysema in 83.5% of patients, and serious abscess formations of the mediastinum and intrathoracic cavity in 38.6% and 29.6%, respectively. The lower esophagus was the most commonly perforated site (77.7%). Management of esophageal perforations included nonoperative treatment in 20 patients (11%) and operative treatment in 162 patients (89%). The overall mortality rate was 6.9%. The survivors had significantly shorter times from symptom appearance to visit (p = 0.0016), and from time to visit to diagnosis confirmation (p = 0.0011). Moreover, patients older than 65 years, white blood cells less than 3000/mm³, C-reactive protein > 10 mg/L, or abscesses in the thoracic cavity showed significantly higher mortality than others.

CONCLUSION

Shortening the time from onset to the start of treatment contributes to reduce mortality in patients with esophageal perforation. Moreover, strict medical treatment is necessary to lower the mortality rate of elderly patients with strong inflammation and abscesses in the thoracic cavity.

Design, analysis, and testing of a motor-driven capsule robot based on a sliding clamper

We propose a motor-driven capsule robot based on a sliding clamper (MCRSC), a device to explore the partially collapsed and winding intestinal tract. The MCRSC is powered by wireless power transmission based on near-field inductive coupling. It comprises a novel locomotion unit, a camera, and a three-dimensional receiving coil, all installed at both ends of the locomotion unit. The novel locomotion unit comprises a linear motion mechanism and a sliding clamper. The former adopts a pair of lead-screw and nut to obtain linear motion, whereas the latter anchors the MCRSC to a specific point of the intestinal tract by expanding its arc-shaped legs. The MCRSC is capable of two-way locomotion, which is activated by alternately executing linear motion and anchoring action. Ex vivo experiments have shown that the MCRSC is able to inspect the colon within a time frame of standard colonoscopy.

Using the Cancer Risk Management Model to evaluate colorectal cancer screening options for Canada

BACKGROUND

Several screening methods for colorectal cancer (crc) are available, and some have been shown by randomized trials to be effective. In the present study, we used a well-developed population health simulation model to compare the risks and benefits of a variety of screening scenarios. Tests considered were the fecal occult blood test (fobt), the fecal immunochemical test (fit), flexible sigmoidoscopy, and colonoscopy. Outcomes considered included years of life gained, crc cases and deaths prevented, and direct health system costs.

METHODS

A natural history model of crc was implemented and calibrated to specified targets within the framework of the Cancer Risk Management Model (crmm) from the Canadian Partnership Against Cancer. The crmm-crc permits users to enter their own parameter values or to use program-specified base values. For each of 23 screening scenarios, we used the crmm-crc to run 10 million replicate simulations.

RESULTS

Using base parameter values and some user-specified values in the crmm-crc, and comparing our screening scenarios with no screening, all screening scenarios were found to reduce the incidence of and mortality from crc. The fobt was the least effective test; it was not associated with lower net cost. Colonoscopy screening was the most effective test; it had net costs comparable to those for several other strategies considered, but required more than 3 times the colonoscopy resources needed by other approaches. After colonoscopy, strategies based on the fit were predicted to be the most effective. In sensitivity analyses performed for the fobt and fit screening strategies, fobt parameter values associated with high-sensitivity formulations were associated with a substantial increase in test effectiveness. The fit was more cost-effective at the 50 ng/mL threshold than at the 100 ng/mL threshold.

CONCLUSIONS

The crmm-crc provides a sophisticated and flexible environment in which to evaluate crc control options. All screening scenarios considered in this study effectively reduced crc mortality, although sensitivity analyses demonstrated some uncertainty in the magnitude of the improvements. Where possible, local data should be used to reduce uncertainty in the parameters.

The histological quality and adequacy of diminutive colorectal polyps resected using jumbo versus hot biopsy forceps

BACKGROUND

Polypectomy with jumbo forceps (JF) and polypectomy with hot biopsy forceps (HBF) are still widely used techniques for removal of diminutive colorectal polyps (DCPs). JF may be more effective for the removal of DCPs because of their larger size.

AIM

To evaluate the histological quality and adequacy of DCPs resected using JF compared with HBF.

METHODS

One hundred and seventy-nine patients with 237 DCPs were included in this study. DCPs were removed using either JP or HBF.

RESULTS

The tissue architecture was good in 29.9 % of the HBF group, in comparison with 90 % of the JF group (p < 0.001). No cautery damage or crash artifact was observed in 93.3 % of JF group and in 8.5 % of HBF group (p < 0.001). Moreover, there were statistically significant differences between the groups with regard to the high level of cautery damage or crush artifact (p < 0.001). The overall diagnostic quality of the specimens removed using JF was significantly better than that of the specimens removed by HBF (96 vs. 80 %, respectively, p < 0.001). There were statistically significant inverse associations between cautery damage or crush artifact and overall diagnostic quality of HBF and JF (r = -0.373, p < 0.001; r = -0.382, p < 0.001, respectively). Surgical margins were determined as negative in 87.5 % of the JF group and in 76.1 % of the HBF group (p = 0.022). A total of 80.8 % of the JF specimens and 30.8 % of the HBF specimens were well evaluated for two lateral and deep surgical margins (p < 0.001).

CONCLUSION

JF was superior to HBF for histopathological interpretation and eradication of DCPs.

Endoscopic duodenal perforation: surgical strategies in a regional centre

BACKGROUND

Duodenal perforation is an uncommon complication of endoscopic retrograde cholangio-pancreatography (ERCP) and a rare complication of upper gastrointestinal endoscopy. Most are minor perforations that settle with conservative management. A few perforations however result in life-threatening retroperitoneal necrosis and require surgical intervention. There is a relative paucity of references specifically describing the surgical interventions required for this eventuality.

METHODS

Five cases of iatrogenic duodenal perforation were ascertained between 2002 and 2007 at Cairns Base Hospital. Clinical features were analyzed and compared, with reference to a review of ERCP at that institution for the years 2005/2006.

RESULTS

One patient recovered with conservative management. Of the other four, one died after initial laparotomy. The other three survived, undergoing multiple procedures and long inpatient stays.

CONCLUSIONS

Iatrogenic duodenal perforation with retroperitoneal necrosis is an uncommon complication of endoscopy, but when it does occur it is potentially life-threatening. Early recognition may lead to a better outcome through earlier intervention, although a protracted course with multiple procedures should be anticipated. A number of surgical techniques may need to be employed according to the individual circumstances of the case.

A blinded comparison of the safety and efficacy of hot biopsy forceps electrocauterization and conventional snare polypectomy for diminutive colonic polypectomy in a porcine model

BACKGROUND

Although linked with perforation, serositis, delayed bleeding, and incomplete resection, hot biopsy forceps electrocauterization (HBF) is still widely used for diminutive colonic polypectomy.

OBJECTIVE

To evaluate the safety and efficacy of HBF in comparison with conventional snare polypectomy (CSP).

DESIGN

Randomized, blinded, controlled trial.

SETTING

Academic endoscopy unit.

SUBJECTS

Ten swine.

INTERVENTION

Eighty-two paired polypectomies (41 HBF, 41 CSP) of small, minimally elevated, artificial lesions. Standardized technique using coagulating current at 25 W. HBF: the tissue was avulsed after 1 to 2 seconds of current caused blanching of the artificial pedicle. CSP: the polyp was removed by snare diathermy.

MAIN OUTCOME MEASUREMENTS

Histopathology of resected specimens and polypectomy sites in colectomy specimens at necropsy (lateral mucosal and depth of ulceration, necrosis and inflammation).

RESULTS

Some (21%) of the HBF specimens were ablated and uninterpretable. All CSP specimens yielded interpretable specimens. Mucosal necrosis adjacent to HBF resection sites varied widely, between 1.5 and 9 mm (mean 5.7 mm, standard deviation ± 2). There was visible mucosa under the HBF ulcer in 14% of cases. The depth of necrosis in the colon wall was significantly different between the two techniques, with partial muscularis propria (MP) necrosis in 14 of 41 lesions (34%) with HBF, compared with 1 of 41 (2%) of CSP (P < .001), and full-thickness MP necrosis in 9 of 41 lesions (22%) with HBF, compared with 1 of 41 (2%) of CSP (P = .014). There was full-thickness MP inflammation in 13 of 41 lesions (32%) with HBF compared with 5 of 41 (12%) of CSP (P = .06). Transmural subserosal inflammation was seen in 13 of 41 lesions (32%) with HBF compared with 4 of 41 (10%) of CSP (P = .027). There was no relationship between visible lateral mucosal injury and depth of injury (rs = -0.07).

LIMITATIONS

Animal study.

CONCLUSION

Despite use of the standardized HBF technique, there is a wide range of lateral mucosal and deep thermal injury as well as residual target mucosa. HBF also results in a significantly greater depth of tissue injury, with a high proportion of transmural necrosis. Ensuring minimal blanching of the mucosa during the procedure does not protect from deep injury. In comparison to conventional snare polypectomy, HBF is imprecise, potentially ineffective, and hazardous.

Colonoscopias realizadas por médicos residentes em hospital universitário: análise consecutiva de 1000 casos

RACIONAL: A colonoscopia tem indicação para diagnóstico em pacientes sintomáticos e é eficaz no rastreamento e vigiância de pacientes assintomáticos. Tem potencial terapêutico em diversas situções, principalmente na remoção das lesões polipóides. A proficiência e a competência do endoscopista é o esteio para o sucesso da colonoscopia diagnóstica e terapêutica. OBJETIVO: Analisar as indicações, os achados diagnósticos, e as complicações de colonoscopias realizadas por médicos residentes em um hospital universitário. MÉTODOS: Foram avaliadas 1.000 colonoscopias consecutivas realizadas por residentes de quarto ano, sob supervisão direta de colonoscopistas experientes. Foram obtidas informações sobre os dados demográficos dos pacientes, o preparo intestinal, as indicações para o procedimento, o sucesso do procedimento, os achados diagnósticos e as complicações. RESULTADOS: Foram examinados total de 596 (59,6%) mulheres e 404 (40,4%) homens. A idade variou de três a 99 anos (média 53,8). O preparo intestinal foi realizado com solução de manitol a 10% em 978 pacientes (97,8%), sendo considerada adequada em 97,6% dos casos. Principais indicações foram: diagnóstico (56,4%), terapêutica (9,6%), rastreamento (17,3%) e vigilância (22%). Taxas de intubação do ceco e válvula ileocecal foram 90,3 e 58,6%, respectivamente. A colonoscopia foi normal em 45,8% dos casos. O diagnóstico mais comum foi diverticulose (18,5%), seguido por pólipos (17%) e neoplasias (6,8%). Achados consistentes com um processo inflamatório foram identificados em 122 pacientes (12,2%) e anomalias vasculares foram detectadas em 11 pacientes (1,1%). Outros diagnósticos representaram 3,9% dos casos. Houve dois casos (0,2%) de complicações (hematoma e hemorragia submucosa), ambos após polipectomia, sem necessidade de intervenção cirúrgica. CONCLUSÃO: Os residentes sob supervisão e orientação de especialistas podem realizar colonoscopias com excelente resultado, baixo índice de complicações e com dados finais comparáveis aos obtidos por endoscopistas experientes.

Endoscopy for upper GI cancer screening in the general population: a cost-utility analysis

BACKGROUND

Colon cancer screening with colonoscopy is an accepted strategy; however, there are limited data regarding the cost-effectiveness of screening for upper GI cancers (esophageal adenocarcinoma with its premalignant precursor Barrett's esophagus, esophageal squamous cell cancer, gastric adenocarcinoma) in the United States.

OBJECTIVE

To evaluate the cost-effectiveness of screening the general population for upper GI cancers by performing an upper endoscopy at the time of screening colonoscopy.

DESIGN

Decision analysis.

SETTING

Third-party-payer perspective with a time horizon of 30 years or until death.

PATIENTS

This study involved 50-year-old patients already undergoing screening colonoscopy.

INTERVENTION

Comparison of two strategies: performing and not performing a screening upper endoscopy at the time of screening colonoscopy.

MAIN OUTCOME MEASUREMENTS

Incremental cost-effectiveness ratio (ICER).

RESULTS

One-time screening for the general population at the age of 50 for upper GI cancers required $115,664 per quality-adjusted life year (QALY) compared with no screening or surveillance. A strategy of screening and surveillance for Barrett's esophagus required only $95,559 per QALY saved. In 1-way sensitivity analyses, the prevalence rates of esophageal adenocarcinoma, esophageal squamous cell cancer, or gastric adenocarcinoma would have to increase by 654%, 1948%, and 337%, respectively, to generate an ICER of less than $50,000 per QALY.

LIMITATIONS

Omission of premalignant conditions for squamous cell cancer and gastric adenocarcinoma.

CONCLUSION

The ICER for screening the general population for upper GI cancers with endoscopy remains high, despite accounting for reduced endoscopy costs and the combined benefits of detecting early esophageal adenocarcinoma, esophageal squamous cell cancer, and gastric adenocarcinoma. However, the ICER compares favorably with commonly performed screening strategies for other cancers.

[Endoscopic aspects in the diagnosis of terminal ileum diseases]

The ileum is approximately the most distal three-fifths of the small intestine and is responsible for the digestion and the absorption of foods. The diagnosis of diseases that affects this segment can be achieved by clinical evaluation and complementary examinations. Not only does ileocolonoscopy allow macroscopical analysis, but also enables biopsies to be carried out for histological evaluation. Only three publications about the description of the endoscopic characteristics of the terminal ileum have been found in the literature. Even so, there have not been found descriptions or classifications in publications that mentioned endoscopic aspect of the terminal ileum, being reported only as normal ileum. Therefore, this strengthens the idea of the lack of knowledge or the non-acceptance of these descriptions and these classifications by the scientific community. Endoscopic aspects of this segment when affected by several diseases vary from normal endoscopically ileum to cases when the macroscopical examination demonstrate specific features of these illnesses. In the present investigation, there are doubts about the need of biopsy of this segment in patients with normal ileoscopy. Moreover, few studies with criteria for macroscopical and microscopical characterization of the ileum were found.

[A case of acute myocardial infarction occurred immediately after endoscopic submucosal dissection]

Endoscopic methods such as endoscopic mucosal resection or endoscopic submucosal dissection (ESD) have been increasingly used for the treatment of gastric adenoma and early gastric cancer. Especially, ESD is very useful since it allows en bloc resection of large lesions. Bleeding and perforation are well known as common complications after ESD. However, there is no report of acute myocardial infarction associated with ESD. We report a case of acute myocardial infarction which was detected immediately after ESD.

Management of esophageal perforations

BACKGROUND

Esophageal perforations remain a life-threatening event requiring rapid diagnosis and treatment. Surgical repair and interventional endoscopic or conservative treatment are the common treatment methods.

METHODS

From 1998 to 2006, the authors retrospectively analyzed 62 patients treated for esophageal perforation. Data were evaluated for cause of perforation, symptoms, therapeutic regimen, complications, and mortality.

RESULTS

The causes of perforation were iatrogenic or suicidal (n = 33) or spontaneous (n = 29). In the first group, the causes were dilation of stenosis (n = 16), endoscopy (n = 7), transesophageal echography (n = 4), ingestion of acid or leach (n = 2), intubation (n = 2), ingestion of a foreign body (n = 1), and migration of a screw after osteosynthesis (n = 1). The spontaneous perforations were caused by tumors (n = 19), Boerhaave syndrome (n = 6), unknown origin (n = 3), and Barrett's ulcer (n = 1). The most frequent symptoms were dysphagia (n = 50), pain (n = 35), fever (n = 24), and vomiting (n = 18). At the time of perforation, 28 patients presented with cancer. Of these 28 patients, 18 had esophageal cancer. The treatment included surgery (n = 32), which consisted of double-layer suture (n = 26) or esophageal resection (n = 6). A total of 30 patients were treated interventionally with a stent (n = 21), clips (n = 1), or without further measures (n = 8). The patients in the surgery group presented with severe primary and postoperative general conditions including renal failure (25%), respiratory insufficiency (65.5%), and need for catecholamines (62.5%). This multiorgan involvement was found only occasionally in the conservative group. The overall hospital mortality rate was 14.5%, involving 9 patients (5 in the surgery group and 4 in the conservative group). Early treatment led to better survival than late treatment with a delay exceeding 24 h.

CONCLUSION

The treatment method still must be chosen on an individual basis. It appears that surgical treatment is necessary in cases of severe general conditions. The data from this study show that surgical repair and conservative treatment may be used successfully. The best outcome was obtained after immediate treatment.

Virtual colonoscopy in stenosing colorectal cancer

BACKGROUND

Between 5 and 10% of the patients undergoing a colonoscopy cannot have a complete procedure mainly due to stenosing neoplastic lesion of rectum or distal colon. Nevertheless the elective surgical treatment concerning the stenosis is to be performed after the pre-operative assessment of the colonic segments upstream the cancer. The aim of this study is to illustrate our experience with the Computed Tomographic Colonography (CTC) for the pre-operative assessment of the entire colon in the patients with stenosing colorectal cancers.

METHODS

From January 2005 till March 2009, we observed and treated surgically 43 patients with stenosing colorectal neoplastic lesions. All patients did not tolerate the pre-operative colonoscopy. For this reason they underwent a pre-operative CTC in order to have a complete assessment of the entire colon. All patients underwent a follow-up colonoscopy 3 months after the surgical treatment. The CTC results were compared with both macroscopic examination of the specimen and the follow-up coloscopy.

RESULTS

The pre-operative CTC showed four synchronous lesions in four patients (9.3% of the cases). The macroscopic examination of the specimen revealed three small sessile polyps (3-4 mm in diameter) missed in the pre-operative assessment near the stenosing colorectal cancer. The follow-up colonoscopy showed four additional sessile polyps with a diameter between 3-11 mm in three patients. Our experience shows that CTC has a sensitivity of 83,7%.

CONCLUSION

In patients with stenosing colonic lesions, CTC allows to assess the entire colon pre-operatively avoiding the need of an intraoperative colonoscopy. More synchronous lesions are detected and treated at the time of the elective surgery for the stenosing cancer avoiding further surgery later on.

[Evaluation of computed tomographic colonography for detection of colorectal polyps]

BACKGROUND

Computed tomographic colonography has been proposed for detection of colorectal polyps instead of colonoscopy in colorectal cancer screening programs.

AIM

To evaluate the performance of computed tomographic colonography in the detection of colorectal polyps with colonoscopy used as the gold standard.

METHODS

We prospectively studied 20 patients at high risk for colorectal neoplasia (14 men and 6 women; mean age, 55 years and 59 years). Computed tomographic colonography was performed immediately before colonoscopy. We inserted a rectal balloon catheter and insufflated the colon with room air to the level that a good distension was observed. Twenty milligrams of hioscin was given immediately before computed tomographic imaging of the abdomen and pelvis in order to minimize the degree of smooth-muscle spasm and peristalsis and to reduce the patient's discomfort.

RESULTS

Computed tomographic colonography images were considered satisfactory in all cases. Colonoscopy detected 85 polyps in 19 of 20 patients (95%). All the observed polyps were successfully removed and examined histologically. The radiological examination correctly identified 8 of 10 polyps 10 mm or more in diameter, 2 of 19 (18,2%) with 5-9 mm, and just 1 of 53 <5mm (9,1%). Seventeen of the 43 adenomatous polyps were > or =5 mm. Eight (47%) were correctly identified on computed tomographic colonography. None of the neoplasias <5 mm were identified on colonography. Nineteen patients preferred colonoscopy in the event of having to repeat on of the two examinations.

CONCLUSION

For the detection of colorectal polyps, computed tomographic colonography seems to be useful only when the result is positive, as the negative results of this examination cannot eliminate the presence of these lesions.

A cost-utility analysis of ablative therapy for Barrett's esophagus

BACKGROUND & AIMS

Recommendations for patients with Barrett's esophagus (BE) include endoscopic surveillance with esophagectomy for early-stage cancer, although new technologies to ablate dysplasia and metaplasia are available. This study compares the cost utility of ablation with that of endoscopic surveillance strategies.

METHODS

A decision analysis model was created to examine a population of patients with BE (mean age 50), with separate analyses for patients with no dysplasia, low-grade dysplasia (LGD), or high-grade dysplasia (HGD). Strategies compared were no endoscopic surveillance; endoscopic surveillance with ablation for incident dysplasia; immediate ablation followed by endoscopic surveillance in all patients or limited to patients in whom metaplasia persisted; and esophagectomy. Ablation modalities modeled included radiofrequency, argon plasma coagulation, multipolar electrocoagulation, and photodynamic therapy.

RESULTS

Endoscopic ablation for patients with HGD could increase life expectancy by 3 quality-adjusted years at an incremental cost of <$6,000 compared with no intervention. Patients with LGD or no dysplasia can also be optimally managed with ablation, but continued surveillance after eradication of metaplasia is expensive. If ablation permanently eradicates >or=28% of LGD or 40% of nondysplastic metaplasia, ablation would be preferred to surveillance.

CONCLUSIONS

Endoscopic ablation could be the preferred strategy for managing patients with BE with HGD. Ablation might also be preferred in subjects with LGD or no dysplasia, but the cost effectiveness depends on the long-term effectiveness of ablation and whether surveillance endoscopy can be discontinued after successful ablation. As further postablation data become available, the optimal management strategy will be clarified.

Distal thoracic oesophageal perforation secondary to blunt trauma: case report

Background

Traumatic perforation of the distal oesophagus due to blunt trauma is a very rare condition and is still associated with a significant morbidity and mortality. This is further exacerbated by delayed diagnosis and management as symptoms and signs are often masked by or ascribed to more common blunt thoracic injuries.

Case report

We present a case of a distal oesophageal perforation, secondary to a fall from a third storey window, which was masked by concomitant thoracic injuries and missed on both computed tomography imaging and laparotomy. The delay in his diagnosis significantly worsened the patient's recovery by allowing the development of an overwhelming chest sepsis that contributed to his death.

Conclusion

Early identification of an intrathoracic oesophageal perforation requires deliberate consideration and is essential to ensure a favorable outcome. Treatment should be individualised taking into account the nature of the oesophageal defect, time elapsed from injury and the patient's general condition.

Cost utility of screening for Barrett's esophagus with esophageal capsule endoscopy versus conventional upper endoscopy

BACKGROUND & AIMS

Screening for Barrett's esophagus with conventional esophagoduodenoscopy (EGD) is recommended to decrease mortality from esophageal adenocarcinoma. Esophageal capsule endoscopy (ECE) has recently been shown to be accurate in detecting Barrett's esophagus. We aimed to compare the cost-effectiveness of screening by ECE with screening by EGD.

METHODS

A Markov model of 50-year-old white men with symptoms of gastroesophageal reflux was constructed to compare screening modalities. The model incorporated direct medical costs and indirect costs of lost productivity and followed the patients until age 80 years or death. Outcomes were analyzed from the societal perspective.

RESULTS

EGD screening prevented 60% of cancer deaths at a cost of $11,254 per quality-adjusted life year gained compared with no screening. ECE prevented 53% of cancer deaths and provided 9 fewer quality-adjusted days at greater cost than EGD. If society were only willing to pay $50,000 per quality-adjusted life year gained, then capsule screening would be preferred if the income of the patient and driver were each greater than $280,682. Otherwise, the findings were robust to all sensitivity analyses.

CONCLUSIONS

Screening for Barrett's esophagus with either EGD or ECE results in similar outcomes, but EGD is the preferred strategy. Both strategies appear cost-effective, and the model does not take into account patient preferences for screening modality or adherence.

The cost-effectiveness of CT colonography in screening for colorectal neoplasia

BACKGROUND

We examined the cost-effectiveness of 2- and 3-dimensional computerized tomography (CT) colonography as a screening test for colorectal neoplasia.

METHODS

We created a Markov model of the natural history of colorectal cancer. Effectiveness of screening was based upon the diagnostic accuracy of tests in detecting polyps and cancer.

RESULTS

CT colonography every 5 or 10 yr was effective and cost-effective relative to no screening. Optical colonoscopy dominates 2-dimensional CT colonography done every 5 or 10 yr. Optical colonoscopy is weakly dominant over 3-dimensional CT colonography done every 10 yr. 3-D CT colonography done every 5 yr is more effective than optical colonoscopy every 10 yr, but costs an incremental 156,000 dollars per life-year gained. Sensitivity analyses show that test costs, accuracy, and adherence are critical determinants of incremental cost-effectiveness. 3-D CT colonography every 5 yr is a dominant strategy if optical colonoscopy costs 1.6 times more than CT colonography. However, optical colonoscopy is a dominant strategy if the sensitivity of CT colonography for 1 cm adenomas is 83% or lower.

CONCLUSIONS

CT colonography is an effective screening test for colorectal neoplasia. However, it is more expensive and generally less effective than optical colonoscopy. CT colonography can be reasonably cost-effective when the diagnostic accuracy of CT colonography is high, as with primary 3-dimensional technology, and if costs are about 60% of those of optical colonoscopy. Overall, CT colonography technology will need to improve its accuracy and reliability to be a cost-effective screening option.

Update on Colorectal Cancer Imaging

Colorectal cancer remains a leading cancer killer worldwide. The disease is both curable and preventable, and yet the importance of widespread screening is only now starting to be appreciated. This article reviews the variety of diagnostic tests, imaging procedures and endoscopic examinations available to detect colorectal cancer and polyps in their early stage and also presents details on various screening options. The critical role of the radiologist is elaborated on including accurate assessment of the tumor extent within the bowel wall and beyond and the detection of lymph node and distant metastases. Staging with CT, MR imaging, endorectal ultrasound, and positron emission tomography are of paramount importance in determining the most appropriate therapy and the risk of tumor recurrence and overall prognosis.

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.

Defining a clinically significant adverse impact of diagnosing Barrett's esophagus

BACKGROUND

Diagnosing a potentially life-threatening disease may adversely affect patient quality of life (QOL) independent of biologic effects. It is unknown whether the mere diagnosis of Barrett's esophagus (BE) adversely impacts patients' preferences (health-state utility) sufficiently to impair the cost-effectiveness of endoscopic screening for esophageal adenocarcinoma.

GOAL

To calculate the threshold impact on utility incurred by diagnosing BE that would allow screening to remain cost-effective.

STUDY

A Markov model was developed to examine strategies of no screening, and screening with surveillance of BE. Patients were 50-year-old white men with symptoms of gastroesophageal reflux followed until 80 years of age or death. The primary outcomes were the threshold decrements in utility incurred by diagnosing BE based on willingness to pay (WTP) of dollar 50,000 and dollar 100,000 per quality-adjusted life-year (QALY) gained.

RESULTS

For a WTP of dollar 50,000/QALY, the decrement in utility could be as great as 9%, meaning that screening is cost-effective as long as diagnosing BE does not impair QOL by more than 9%. For a WTP of dollar 100,000, the decrement could be as great as 10.5%.

CONCLUSIONS

The decrement in utility caused by diagnosing BE may be substantial without compromising the cost-effectiveness of endoscopic screening.

Virtual colonoscopy for colorectal cancer screening: current status

Computed tomography colonography (CTC) (also known as ‘virtual colonoscopy’) is a noninvasive method of imaging the colon using helical CT. Although CTC has been shown to be useful for certain clinical indications, it has not yet been endorsed as a colorectal cancer screening test. The purpose of this article is to review the current status of CTC for colorectal cancer screening. CTC is an accurate method to detect colonic polyps and to select patients who would benefit from colonoscopy. The major advantages of CTC over conventional colonography include its relatively low risk and greater tolerance by patients. In this article, the CTC procedure and results of clinical trials are reviewed, as well as potential pitfalls related to CTC performance and interpretation. Finally, radiation dose, the discovery of incidental extracolonic findings with CTC, bowel preparation methods, and computer-aided diagnosis are addressed.

Sedation and the technical performance of colonoscopy

The use of sedation for routine endoscopic procedures, including colonoscopy, varies widely across cultures. This variation in sedation practice is greater than any other culturally based variation in the technical performance of endoscopy. This article sequentially reviews the technical performance of colonoscopy in patients who undergo unsedated colonoscopy, sedation with narcotics and benzodiazepines, and deep sedation with propofol. For each of these approaches to colonoscopy, the advantages and disadvantages also are listed and discussed.

The cost-effectiveness of biomarkers for predicting the development of oesophageal adenocarcinoma

BACKGROUND

The recommended surveillance strategy for oesophageal adenocarcinoma may prevent as few as 50% of cancer deaths. Tissue biomarkers have been proposed to identify high-risk patients.

AIM

To determine performance characteristics of an ideal biomarker, or panel of biomarkers, that would make its use more cost-effective than the current surveillance strategy.

METHODS

We created a Markov model using data from published literature, and performed a cost-utility analysis. The population consisted of 50-year-old Caucasian men with gastro-oesophageal reflux, who were monitored until age 80. We examined strategies of observation only, current practice (dysplasia-guided surveillance), surveillance every 3 months for patients with a positive biomarker (biomarker-guided surveillance), and oesophagectomy immediately for a positive biomarker (biomarker-guided oesophagectomy). The primary outcome was the threshold cost and performance characteristics needed for a biomarker to be more cost-effective than current practice.

RESULTS

Regardless of the cost, the biomarker needs to be at least 95% specific for biomarker-guided oesophagectomy to be cost-effective. For biomarker-guided surveillance to be cost-effective, a $100 biomarker could be 80% sensitive and specific.

CONCLUSIONS

Biomarkers predicting the development of oesophageal adenocarcinoma would need to be fairly accurate and inexpensive to be cost-effective. These results should guide the development of biomarkers for oesophageal adenocarcinoma.

Why do complications of gastrointestinal disease and procedures come as serial rather than singular events?

BACKGROUND

It often appears as if complications arising from gastrointestinal disease and interventional procedures come in 'series' and 'cluster' in individual patients.

AIM

The aim of this study was to analyse the clustering of complications in terms of stochastic modelling and Markov chains.

METHODS

A patient with gastrointestinal disease is simulated to move along either a 'bad track' associated with multiple consecutive complications or a 'good track' free of complications, the transitions within each track and between the two tracks being governed by probability values.

RESULTS

Because the occurrence of a single complication increases the risk of further complications, subjects who encounter their first complication are more likely to experience a second, third or even more complications, before they leave the 'bad track' and their personal chain of cascading complications becomes discontinued. The model of a Markov chain explains why the overall number of complications in the total population of patients with digestive disease remains low even if individual patients are expected to encounter more than a single complication.

CONCLUSIONS

Published complication rates for gastrointestinal procedures underestimate the true risk to the patient, because they do not consider the added vulnerability to cascading complications after the first event.

Colonoscopic Perforations: Incidence, Management, and Outcomes

Fiberoptic colonoscopy provides superior diagnostic and therapeutic capabilities in the treatment of lower gastrointestinal disease processes. A well-recognized, but uncommon, complication during the procedure is perforation. The purpose of this study was to determine the incidence of colonoscopic perforation, define risk factors, assess the management of these complications, and evaluate outcomes. From January 1997 through December 2003, 43,609 colonoscopies were performed in our medical center. There were 14 (0.032%) perforations (1 in 3115 procedures); 7 from diagnostic and 7 from therapeutic procedures. General surgeons performed 1243 procedures (2.9%), and their rate of perforation was 0.080 per cent compared with 0.031 per cent for gastroenterologists during the same period. Half of the perforations occurred in the rectosigmoid, and the most common mechanism was mechanical (n = 6). Perforation was identified immediately during endoscopy in 50 per cent of the patients. Thirteen of 14 perforations were treated within 24 hours; 1 was delayed 48 hours. Initial surgical management was undertaken in 11/14 patients. Initial nonoperative treatment was attempted in three and was successful in only one patient. The mean length of stay following perforation was 11.2 days (range, 4–36 days). Three patients (21.4%) had 7 postoperative complications. Colonoscopic perforations are uncommon but can be recognized early and managed surgically with acceptable morbidity and postoperative length of stay.

Radiologic imaging modalities in the diagnosis and management of colorectal cancer

Colorectal carcinoma poses a serious public health threat. Detection in its early stages in the best predictor for long-term survival, which is the impetus for population-based screening programs. We believe that full-colon imaging by either DCBE or colonoscopy is necessary for colon cancer screening because flexible sigmoidoscopy, even if perfect, only detects 50% to 60% of colon cancers, a rate far worse than even the worst rate reported for single-contrast barium enema. Screening for colon cancer with flexible sigmoidoscopy is equivalent to performing a "left" mammogram for the detection of breast cancer. The role of CT colonography is still to be determined. When confronted with a symptomatic patient, barium enema is applied in conjunction with CT to detect primary colorectal carcinoma, to differentiate it from other benign and malignant processes involving the colon, and to assess for disease extent before surgery in selected high-risk patient populations. Pelvic MRI may be useful in the preoperative assessment of patients with rectal carcinoma as a means for assisting surgical planning. CT, MRI, and barium enema are used in postoperative follow-up for detecting local recurrence and distant spread. In response to known difficulty in discriminating between normal postoperative changes and tumor recurrence and in determining the nature of certain liver lesions, FDG-PET has been approved for the detection and localization of recurrent colorectal cancer in patients with rising CEA levels and indeterminate findings on standard imaging studies. Given its current promise of offering high sensitivity, specificity, and accuracy, the indications for PET may well expand in the future, but its final role in still to be determined.

Management of Anticoagulation for Gastrointestinal Endoscopic Procedures

Endoscopic procedures, particularly those requiring mucosal biopsy or polypectomy, are associated with an increased risk of gastrointestinal bleeding during or after procedure. This risk is increased in patients treated with chronic anticoagulant therapy. Anticoagulant therapy needs to be withheld for certain high-risk endoscopic procedures to prevent bleeding complications. However, this may expose some patients to an increased risk of thromboembolic complications during this period, particularly in patients with recent episodes of venous or arterial thromboembolism and those with prosthetic mechanical valves. Identifying patients at a high risk for thromboembolic complications and more aggressively managing their anticoagulant regimen (by switching to heparin) in preparation for the endoscopic procedure decreases the length of time they remain unanticoagulated and helps minimize complications. Low molecular weight heparin as a bridging therapy in preparation for endoscopic procedures can obviate unnecessary hospitalization and is an attractive strategy for managing high-risk patients.

Which colon cancer screening test? A comparison of costs, effectiveness, and compliance

PURPOSE

Recent media reports have advocated the use of colonoscopy for colorectal cancer screening. However, colonoscopy is expensive compared with other screening modalities, such as fecal occult blood testing and flexible sigmoidoscopy. We sought to determine the cost effectiveness of different screening strategies for colorectal cancer at levels of compliance likely to be achieved in clinical practice.

METHODS

A Markov decision model was used to examine screening strategies, including fecal occult blood testing alone, fecal occult blood testing combined with flexible sigmoidoscopy, flexible sigmoidoscopy alone, and colonoscopy. The timing and frequency of screening was varied to assess optimal screening intervals. Sensitivity analyses were conducted to assess the factors that have the greatest effect on the cost effectiveness of screening.

RESULTS

All strategies are cost effective versus no screening, at less than $20,000 per life-year saved. Direct comparison suggests that the most effective strategies are twice-lifetime colonoscopy and flexible sigmoidoscopy combined with fecal occult blood testing. Assuming perfect compliance, flexible sigmoidoscopy combined with fecal occult blood testing is slightly more effective than twice-lifetime colonoscopy (at ages 50 and 60 years) but is substantially more expensive, with an incremental cost effectiveness of $390,000 per additional life-year saved. However, compliance with primary screening tests and colonoscopic follow-up for polyps affect screening decisions. Colonoscopy at ages 50 and 60 years is the preferred test regardless of compliance with the primary screening test. However, if follow-up colonoscopy for polyps is less than 75%, then even once-lifetime colonoscopy is preferred over most combinations of flexible sigmoidoscopy and fecal occult blood testing. Costs of colonoscopy and proportion of cancer arising from polyps also affect cost effectiveness.

CONCLUSIONS

Colonoscopic screening for colorectal cancer appears preferable to current screening recommendations. Screening recommendations should be tailored to the compliance levels achievable in different practice settings.

Complications of diagnostic and therapeutic colonoscopy within a defined population in Sweden

BACKGROUND

Colonoscopy, introduced in the late 1960s, has become the principal method for diagnosis, treatment, and follow-up of colorectal diseases. Being invasive, colonoscopy is associated with a risk of complications. The aim of this study was to analyze the rate of complications of diagnostic and therapeutic colonoscopy in a population-based setting.

METHODS

All colonoscopy records for 1979 to 1995 in 1 Swedish county (population 258,000) were retrieved. Information was obtained about patients' demographics, date of examination, endoscopist, indications, findings, colonoscopy type, completion level, and complications. Records were linked to the Cause of Death Register and the Swedish Hospital Discharge Register to ascertain mortality and morbidity.

RESULTS

In 6066 colonoscopies, the overall morbidity was 0.4% (diagnostic 0.2%, therapeutic 1.2%). The most frequent complications were bleeding (0.2%) and perforation (0.1%), with no colonoscopy-related mortality. Bleeding was confined to therapeutic colonoscopy and occurred immediately, mainly after removal of large polyps with thick stalks. Perforations at diagnostic colonoscopy occurred in the left colon; they were diagnosed sooner than perforations associated with therapeutic colonoscopy where the cecum was the most frequent site. The bleeding rate was correlated to the experience of the endoscopists.

CONCLUSIONS

Colonoscopy is a safe procedure, and the rate of adverse events in this population-based setting was low.

Colonoscopic perforations

PURPOSE

This study was designed to assess the medical and surgical treatment of colonoscopic perforations.

METHODS

A retrospective review of colonoscopic perforations from 1970 to 1999 was performed.

RESULTS

In 30 years, 34,620 colonoscopies resulted in 31 (0.09 percent) perforations. Eighteen (58 percent) resulted from therapeutic colonoscopies, whereas 13 (42 percent) occurred after diagnostic colonoscopies. Sixteen perforations (52 percent) were identified during the procedure, 13 (42 percent) within 24 hours, and two (6 percent) within 48 hours. Twenty patients (65 percent) underwent surgical therapy, and 11 (35 percent) were treated medically with intestinal rest and intravenous antibiotics. In the medically treated group, one patient required rehospitalization for percutaneous drainage of an intra-abdominal abscess, and one patient died after requesting no further treatment because of an underlying terminal medical condition. Three patients failed medical treatment and required surgical intervention. One underwent repair with proximal diversion, whereas the remaining two received a colorrhaphy without resection or diversion. In the surgical treatment group, nine patients received colorrhaphy without diversion, seven underwent resection with primary anastomosis, and four had resection with diversion.

CONCLUSION

Selected patients with colonoscopic perforation may be safely treated nonoperatively. Surgical treatment is reserved for patients with a large perforation or diffuse peritonitis.

Cost-effectiveness of colorectal cancer screening

PURPOSE

To determine the most cost-effective colorectal cancer screening strategy costing less than $100,000 per life-year saved and to determine how available strategies compare with each other.

MATERIALS AND METHODS

Standardized methods were used to calculate incremental cost-effectiveness ratios (ICERs) from published estimates of cost and effectiveness of colorectal cancer screening strategies, and the direction and magnitude of any effect on the ratio from parameter estimate adjustments based on literature values were estimated.

RESULTS

Strategies in which double-contrast barium enema examination was performed emerged as optimal from all studies included. In average-risk individuals, screening with double-contrast barium enema examination every 3 years, or every 5 years with annual fecal occult blood testing, had an ICER of less than $55,600 per life-year saved. However, double-contrast barium enema examination screening every 3 years plus annual fecal occult blood testing had an ICER of more than $100,000 per life-year saved. Colonoscopic screening had an ICER of more than $100,000 per life-year saved, was dominated by other screening strategies, and offered less benefit than did double-contrast barium enema examination screening.

CONCLUSION

Double-contrast barium enema examination can be a cost-effective component of colorectal cancer screening, but further modeling efforts are necessary.

A prospective analysis of 13,580 colonoscopies. Reevaluation of credentialing guidelines

BACKGROUND

The aims of this study were to assess the safety and efficacy of surgeons performing colonoscopy, and to use the results to reevaluate currently available credentialing guidelines.

METHODS

A prospective outcomes study was designed to include all members of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES). End points were related to the efficacy and safety of colonoscopy. Credentialing guidelines were reviewed.

RESULTS

Between April 1998 and September 1999 13,580 colonoscopies were prospectively entered into a database. The most common indications were rectal bleeding, colonic polyps, and change in bowel habits. The colonoscopy was normal or revealed only diverticulosis or nonspecific inflammation in 8,473 (62.4%), lower gastrointestinal bleeding in 4 (0.03%), polyps in 4,645 (34.2%), and tumors in 458 (3.4%) patients. The most common biopsy methods for polyps or tumors were the snare (n = 1,728; 34%), the hot (n = 1,600; 31%), and the cold (n = 1,340; 22%) procedures. The colonoscopy was complete in 12,495 cases (92%), requiring a mean procedure time of 22.7 min (range, 1-170 min). Intraprocedural complications included arrhythmia (n = 14; 0.1%), bradycardia (n = 115; 0.8%), hypotension (n = 171; 1.2%), and hypoxia (n = 806; 5.6%). Postprocedural complications were seen in 27 patients (0.2%). Bleeding (n = 10; 0.07%) was managed by observation alone (n = 9; 0.06%) and repeat colonoscopy with transfusion (n = 1; 0.01%). Perforation (n = 10; 0.07%) was treated successfully by observation with conservative management (n = 5; 0.05%) and surgery (n = 5; 0.05%); severe abdominal pain (n = 4; 0.03%) was managed by observation and conservative therapy; and bronchospasm (n = 2; 0.015%) was managed by observation and supportive care. One single mortality (0.007%) was that of a 70-year-old man with a massive lower gastrointestinal hemorrhage who had a cardiac arrest in the recovery room following colonoscopy. The complication rate was not significantly associated statistically with either the level of experience or the number of prior or annual colonoscopies. However, prior colonoscopic experience did have an impact on the completion rate (p < 0.001) and was inversely proportional to the time to completion (p < 0.001). Similarly, the number of annual colonoscopies affected the completion rate and was inversely correlated with the time to completion (p < 0.001).

CONCLUSIONS

This large prospective outcomes study showed that colonoscopy performed by surgeons can be rapidly and successfully done with acceptably low morbidity and mortality. There was no association between experience and complications. However, a minimum of 50 prior colonoscopies and 100 annual colonoscopies were associated with a significant improvement in the rate of completion. There was also a significant correlation between both prior and ongoing annual experience and the time required for the examination. No minimum number of cases can be mandated for credentialing to perform "safe" colonoscopies.

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

OBJECTIVES

To assess the incidence, clinical features, and management of endoscopic colon perforations in a large number of patients at a major medical teaching center.

METHODS

A retrospective review of medical records of all patients with colon perforations from endoscopy over a 10-yr period.

RESULTS

A total of 10,486 colonoscopies were performed over a 10-yr period. There were 20 (0.19%) perforations and two (0.019%) deaths related to colonoscopy and two perforations with no deaths in 49,501 sigmoidoscopies (0.004%). The majority of perforations (65%) occurred in the sigmoid colon. The mean age of the patients was 72 yr (range, 48-87 yr). Multivariate analysis using gender and age showed that female gender was an independent predictor of a higher risk of perforation (p < 0.05). Electrocautery injury (36%) and mechanical injury (32%) from the tip and shaft of the endoscope were the major causes for perforation. Most patients (91%) presented within 48 h of endoscopy. Nine patients (47%) required a surgical resection with primary anastomosis; seven (37%) required a simple closure. The average hospital length of stay was 7.7 +/- 2.8 days. Although trainee endoscopists were involved in only 20% of the colonoscopies performed, eight (40%) perforations occurred while the training fellow was involved in the case. However, this increased risk of perforation with a training fellow was not statistically significant (p = 0.625).

CONCLUSIONS

Colonoscopy can result in significant morbidity and carries a small risk of death. Sigmoidoscopy has lower risk. The following situations may represent increased risk to colonoscopy patients: unusual difficulty in traversing the sigmoid colon; difficult examinations in female patients, and difficult examinations performed by trainee physicians.