Colonic gas explosion during therapeutic colonoscopy with electrocautery

Therapeutic colonoscopy with electrocautery is widely used around the world. Adequate colonic cleansing is considered a crucial factor for the safety of this procedure. Colonic gas explosion, although rare, is one of the most frightening iatrogenic complications during colonoscopy with electrocautery. This complication is the result of an accumulation of colonic gases to explosive concentrations, but may be prevented by meticulous bowel preparation. The purpose of this review is to discuss the indications and the types of bowel preparations for therapeutic colonoscopy, and to contribute recommendations for the adequate bowel preparation for colonoscopy with electrocautery.     

Colonic gas explosion during therapeutic colonoscopy with electrocautery

Therapeutic colonoscopy with electrocautery is widely used around the world. Adequate colonic cleansing is considered a crucial factor for the safety of this procedure. Colonic gas explosion, although rare, is one of the most frightening iatrogenic complications during colonoscopy with electrocautery. This complication is the result of an accumulation of colonic gases to explosive concentrations, but may be prevented by meticulous bowel preparation. The purpose of this review is to discuss the indications and the types of bowel preparations for therapeutic colonoscopy, and to contribute recommendations for the adequate bowel preparation for colonoscopy with electrocautery.     

Colonic preparation correlates with fasting breath hydrogen in patients undergoing colonoscopy

BACKGROUND/AIMS: Fasting breath hydrogen has been reported to be low after fasting and polyethylene glycol ingestion. However, the relationship between fasting breath hydrogen and colonic preparation for colonoscopy has not been studied before. We evaluated fasting breath hydrogen in patients undergoing colonoscopy and correlated it with the quality of colonic preparation. METHODOLOGY: One day before colonoscopy, the patients ingested clear liquid diet and starting in the afternoon the day before colonoscopy they drank polyethylene glycol 8oz every 10 minutes for 3 hours. They fasted overnight. Fasting breath hydrogen was measured using an EC 60 gastrolyzer. Colonic preparation was rated as excellent, fair or poor. The colonoscopic findings were noted. RESULTS: There were 69 male patients. 89% had excellent or fair colonic preparation (Group A) 11% had poor preparation (Group B). Fasting breath hydrogen in Group B patients 14.5 +/- 1.5 ppm was significantly higher compared to that in Group A patients 2.2 +/- 0.2 ppm (p < 0.005 t-test). In other respects the two groups were similar. CONCLUSIONS: Patients undergoing colonoscopy after polyethylene glycol ingestion who have poor colonic preparation have higher fasting breath hydrogen compared to those who have excellent/fair colonic preparation. The clinical implication of this observation is discussed.     

Leptin in pituitary adenomas--a novel paracrine regulatory system

A growing number of physiological and pathophysiological processes have been shown to be influenced by leptin apart from its first recognised role as a modulator of hypothalamic appetite and weight control centers. We investigated the presence and pattern of distribution of leptin mRNA and the mRNA of the long isoform of the leptin receptor in the normal pituitary and in different types of pituitary adenomas. We also studied leptin secretion from human pituitary tumors in culture, and the in vitro pituitary hormone release following stimulation with human leptin. Leptin mRNA expression was detected at a low level of expression in 50% of tumors but in none of the normal pituitaries. By immunohistochemistry, leptin was present in occasional scattered cells in the normal pituitary and in pituitary tumors. The leptin receptor long isoform was detected in the majority (65%) of pituitary tumors and in all normal pituitaries. It did not segregate with any particular tumor type, and varying levels of expression were detected between the tissues studied. 34% of pituitary adenomas showed leptin release into the incubation media during in vitro culture. Leptin mRNA, the mRNA of the long isoform of the receptor, or in vitro leptin release, did not correlate with tumor type or with any of the other pituitary hormones released. In vitro leptin stimulation of pituitary tumors caused stimulation of FSH and a-subunit secretion from a non-functioning adenoma and TSH secretion from a somatotroph adenoma. As the co-localisation of ACTH and leptin in corticotroph cells was previously suggested, we investigated whether in vivo ACTH release is accompanied by a simultaneous plasma leptin level rise (i) in peripheral plasma samples after food intake-induced ACTH rise in healthy obese and nonobese individuals and (ii) in petrosal sinus samples after CRH injection in Cushing's disease patients. Our data suggest that a rise in ACTH levels is not accompanied by detectable rise in leptin levels in peripheral and in petrosal sinus blood samples. In summary, leptin is synthesized and stored within the pituitary and may modulate other pituitary hormone secretion, although probably it does not contribute to plasma leptin level changes. Pituitary leptin may therefore be a novel paracrine regulator of pituitary function.     

Colonic preparation before colonoscopy in constipated and non-constipated patients:A randomized study

AIM: To compare the efficacy of different doses of sodium phosphate(NaP) and polyethylenglicol(PEG) alone or with bisacodyl for colonic cleansing in constipated and non-constipated patients.METHODS: Three hundred and forty-nine patients,older than 18 years old,with low risk for renal damage and who were scheduled for outpatient colonoscopy were randomized to receive one of the following preparations(prep): 90 mL of NaP(prep 1);45 mL of NaP + 20 mg of bisacodyl(prep 2);4 L of PEG(prep 3) or 2 L of PEG + 20 mg of bisacodyl(prep 4).Randomization was stratified by constipation.Patients,endoscopists,endoscopists’ assistants and data analysts were blinded.A blinding challenge was performed to endoscopist in order to reassure blinding.The primary outcome was the efficacy of colonic cleansing using a previous reported scale.Secondary outcomes were tolerability,compliance,side effects,endoscopist perception about the necessity to repeat the study due to an inadequate colonic preparation and patient overall perceptions.RESULTS: Information about the primary outcome was obtained from 324 patients(93%).There were no significant differences regarding the preparation quality among different groups in the overall analysis.Compliance was higher in the NaP preparations being even higher in half-dose with bisacodyl: 94%(prep 1),100%(prep 2),81%(prep 3) and 87%(prep 4)(2 vs 1,3 and 4,P < 0.01;1 vs 3,4,P < 0.05).The combination of bisacodyl with NaP was associated with insomnia(P = 0.04).In non-constipated patients the preparation quality was also similar between different groups,but endoscopist appraisal about the need to repeat the study was more frequent in the half-dose PEG plus bisacodyl than in whole dose NaP preparation: 11%(prep 4) vs 2%(prep 1)(P < 0.05).Compliance in this group was also higher with the NaP preparations: 95%(prep 1),100%(prep2) vs 80%(prep 3)(P < 0.05).Bisacodyl was associated with abdominal pain: 13%(prep 1),31%(prep 2),21%(prep 3) and 29%(prep 4),(2,4 vs 1,2,P < 0.05).In constipated pati     

A survey of sedation practices for colonoscopy in Canada

BACKGROUND:

There are limited data regarding the use of sedation for colonoscopy and concomitant monitoring practices in different countries.

METHODS:

A survey was mailed to 445 clinician members of the Canadian Association of Gastroenterology and 80 members of the Canadian Society of Colon and Rectal Surgeons in May and June 2009.

RESULTS:

Sixty-five per cent of Canadian Association of Gastroenterology members and 69% of Canadian Society of Colon and Rectal Surgeons members responded with the full survey. Most endoscopists reported using sedation for more than 90% of colonoscopies. The most common sedation regimen was a combination of midazolam and fentanyl. Propofol, either alone or with another drug, was used in 12% of cases. A higher proportion (94%) of adult gastroenterologists who routinely used propofol were highly satisfied compared with those using other sedative agents (45%; P<0.001). Fifty per cent of adult gastroenterologists and 29% of surgeons who were not currently using propofol expressed interest in starting to use it for routine colonoscopies. Only a single nurse was present in the endoscopy room during colonoscopy performed by two-thirds of the endoscopists.

CONCLUSIONS:

Results of the present survey suggest that gastroenterologists in Canada use sedation for colonoscopy in more than 90% of their patients. There was higher satisfaction among gastroenterologists who used propofol routinely for all colonoscopies. Most endoscopy rooms were staffed by a single nurse, which may limit further increases in the use of propofol. Further studies are needed to determine optimal staffing of endoscopy units with and without the use of propofol. Sedation practices of general surgery endoscopists need to be evaluated.     

Colonic lymphangioma.

Eleven cases of colonic lymphangioma, including 3 that have not been reported previously, are reviewed. Radiologic analysis reveals that 9 presented as polypoidal mucosal lesions and only 2 had characteristic features at a submucosal lesion. A predominant occurence in females (70%) and during the sixth and seventh decades are noted.     

Colonic volvulus.

OBJECTIVE: To review the incidence of volvulations in our workplace, to study the procedures employed in its treatment, and to discuss our results during the last 20 years. MATERIAL AND METHODS: A series of colonic volvulus treated between 1978 and 1998 at one hospital is presented. RESULTS: We reviewed 41 cases. Volvulus locations are: sigmoid colon: 21, caecum: 17, transverse colon: 2, and splenic flexure: 1. Mortality rates according to the type of volvulus and type of operative procedure is analyzed. Four cases of volvulus recurrence (9%). CONCLUSIONS: Treatment guidelines for the approach to colonic volvulus are presented.     

Diagnostic colonoscopy.

Colonoscopy is employed in prevention, diagnosis, follow-up and treatment of colorectal diseases. The technological advancement of colonoscopes and supplementary equipment, has broadened indications for colonoscopy. However, since it is an invasive method with potential complications and hazards it should be performed by specialists capable of preventing, recognizing and treating them. The authors report their personal experience with 1,234 colonoscopies. The most frequent indications were changes in bowel habits and rectal bleeding in 35.1% and 30.5% cases respectively. The patients were given 10% mannitol for bowel cleansing and inadequate bowel cleansing in only 15 (1.2%) so that the colonoscopy could not be completed. The overall incidence of perforation was 0.16%. Three hundred and one polypectomies were performed and two cases (0.75%) of bleeding were noted.     

Primary colonoscopy.

There is good evidence that colonoscopy, in expert hands, is the most accurate investigation for the diagnosis of colorectal disease, and it also allows histological confirmation and therapeutic procedures to be carried out. Furthermore, by screening high-risk groups together with regular follow-up of patients with known colorectal neoplasia and surveillance of long-standing ulcerative colitis patients, it may be possible to reduce the incidence of colorectal cancer. However, at the present time, the lack of widespread availability and the variability in the quality of examinations precludes the employment of colonoscopy as the first-line investigation in colorectal disease. Flexible sigmoidoscopy combined with good quality double contrast barium enema is a reasonable alternative in the majority of cases, reserving colonoscopy for investigation of the elderly and high-risk patients, together with surveillance of patients with premalignant conditions. Technologically, colonoscopy has probably reached its peak and it is now necessary to make provision for more widely available colonoscopy services, provided by adequately trained endoscopists who can guarantee total colonoscopy in more than 90% of cases safely and rapidly. This requires structured training programmes for gastrointestinal physicians and surgeons and ultimately changes in patterns of working practice if adequate numbers of colonoscopy sessions capable of dealing with a steadily increasing workload are to be achieved.     

Patient interest in video recording of colonoscopy:A survey

AIM:To find if patients are interested in obtaining a video recording of their colonoscopy procedure.METHODS:We conducted a survey of outpatients presenting for colonoscopy regarding their interest in obtaining a video recording of their colonoscopy.RESULTS:Two hundred and forty-eight patients(mean age 57.9 years;57% male) were surveyed.Two hundred and one patients(81%) were interested in obtaining a video recording.No significant predictors of patients‘ interest in the video recording were identified.After...     

Colonic adenomas: prevalence and incidence rates, growth rates, and miss rates at colonoscopy

Cost-effective use of colonic imaging studies can be achieved through an understanding of the prevalence, incidence, growth, and miss rates of colon adenomas. High adenoma prevalence rates are associated with increasing age, male gender, and a family history of colorectal cancer or multiple first-degree relatives with colorectal neoplasia or neoplasia diagnosed at a young age. The incidence rate of advanced adenomas is higher in patients with multiple adenomas and is likely also associated with a family history of colorectal cancer, increased age, and large adenoma size at the index examination. Direct observational data on growth rates suggests that adenomas <1 cm in size have a fairly stable size over a 3-year interval. Although colonoscopy is the most sensitive colonic imaging study, substantial miss rates for small adenomas are inherent to the procedure. Advancements in endoscopic technology should lead to reduced miss rates, allowing expansion of intervals between examinations while reducing negative outcomes of fatal interval cancers.