Biomedical subjects

Michael D Saunders

Publications and source records attributed to Michael D Saunders.

6 recordsLinked to original sources

PubMed2006

Incidence of minor complications and time lost from normal activities after screening or surveillance colonoscopy.

BACKGROUND: Few studies address the development of minor complications after screening or surveillance colonoscopy. OBJECTIVES: Our purpose was to examine in previously asymptomatic people the incidence of new symptoms after colonoscopy, risk factors for symptoms, and patients' perceptions of this examination. DESIGN: Prospective cohort study. Patients completed a standardized interview at 7 and 30 days after colonoscopy. PATIENTS: A total of 502 patients aged 40 years and older undergoing colonoscopy for colorectal cancer screening, surveillance, or follow-up of another abnormal screening test result. Patients were excluded if they had a history of inflammatory bowel disease, visible GI bleeding, or anemia. MAIN OUTCOME MEASURES: Incidence of minor complications and patient perceptions about colonoscopy. RESULTS: Minor complications occurred in 162 subjects (34%) before day 7 and in 29 subjects (6%) between day 7 and day 30, most commonly bloating (25%) and abdominal pain (11%). Six subjects had unexpected emergency department visits or hospitalizations within 30 days, including 2 with postpolypectomy bleeding. On multivariate analysis, minor complications were more common in women (odds ratio 1.78, 95% CI 1.21-2.62) and when the procedure lasted 20 minutes or longer. Bowel preparation was rated the most difficult part of the examination for 77%. Most subjects (94%) lost 2 or fewer days from normal activities for the colonoscopy itself, preparation, or recovery. CONCLUSIONS: Minor complications were common after screening and surveillance colonoscopy. The bowel preparation was the most difficult part of the examination for most patients. Most subjects lost 2 or fewer days from normal activities because of colonoscopy.

Adult↗

PubMed2005

A prospective study comparing endoscopy and EUS in the evaluation of GI subepithelial masses.

BACKGROUND: The purpose of this study is to prospectively evaluate the performance characteristics of endoscopy and EUS in the diagnosis of GI subepithelial masses. METHODS: A total of 100 consecutive patients referred for the evaluation of a suspected GI subepithelial lesion were prospectively studied with endoscopy followed by EUS. Size, color, mobility, location (intramural or extramural), consistency (solid, cystic, or vascular), and presumptive diagnosis were recorded at the time of endoscopy. EUS then was performed, and size, echogenicity, location, and presumptive diagnosis were determined. RESULTS: A total of 100 subepithelial lesions were evaluated. Endoscopy had 98% sensitivity and 64% specificity in identifying intramural lesions. Size measurement by endoscopy correlated with size measurement by EUS (r = 0.88). Histology was obtained in 23 cases, with the presumptive EUS diagnosis correct in only 48% of cases. Most incorrect EUS diagnoses occurred with hypoechoic 3rd and 4th layer masses. CONCLUSIONS: Endoscopy has high sensitivity but low specificity in identifying the location (intramural or extramural) of subepithelial lesions. In addition, EUS imaging alone is insufficient to accurately diagnose 3rd and 4th layer hypoechoic masses, and histologic confirmation should be obtained whenever possible.

Adult↗

PubMed2004

Acute colonic pseudoobstruction.

Acute colonic pseudoobstruction (ACPO) is a clinical condition of acute large bowel obstruction without mechanical blockage. ACPO occurs most often in hospitalized patients with serious underlying medical and surgical conditions. ACPO is an important cause of morbidity and mortality. The pathogenesis of ACPO is not completely understood but likely results from an imbalance in the autonomic regulation of colonic motor function. Metabolic or pharmacologic factors, as well as spinal or retroperitoneal trauma, may alter the autonomic regulation of colonic function, leading to excessive parasympathetic suppression or sympathetic stimulation. This imbalance results in colonic atony and pseudoobstruction. Early recognition and appropriate management are critical to minimizing morbidity and mortality. The mortality rate is estimated at 40% when ischemia or perforation occurs. The best documented treatment of ACPO is intravenous neostigmine, which leads to prompt decompression in the majority of patients after a single infusion. In patients failing or having contraindications to neostigmine, colonoscopic decompression is the active intervention of choice. Surgery is reserved for those with overt peritonitis or perforation.

Acute Disease↗

PubMed2004

Acute pancreatitis after EUS-guided FNA of solid pancreatic masses: a pooled analysis from EUS centers in the United States.

BACKGROUND: The aim of this study was to determine the frequency and the severity of pancreatitis after EUS-guided FNA of solid pancreatic masses. A survey of centers that offer training in EUS in the United States was conducted. METHODS: A list of centers in which training in EUS is offered was obtained from the Web site of the American Society for Gastrointestinal Endoscopy. Designated program directors were contacted via e-mail. The information requested included the number of EUS-guided FNA procedures performed for solid pancreatic masses, the number of cases of post-procedure pancreatitis, and the method for tracking complications. For each episode of pancreatitis, technical details were obtained about the procedure, including the location of the mass, the type of fine needle used, the number of needle passes, and the nature of the lesion. RESULTS: Nineteen of the 27 programs contacted returned the questionnaire (70%). In total, 4909 EUS-guided FNAs of solid pancreatic masses were performed in these 19 centers over a mean of 4 years (range 11 months to 9 years). Pancreatitis occurred after 14 (0.29%): 95% CI[0.16, 0.48] procedures. At two centers in which data on complications were prospectively collected, the frequency of acute pancreatitis was 0.64%, suggesting that the frequency of pancreatitis in the retrospective cohort (0.26%) was under-reported (p=0.22). The odds that cases of pancreatitis would be reported were 2.45 greater for the prospective compared with the retrospective cohort (95% CI[0.55, 10.98]). The median duration of hospitalization for treatment of pancreatitis was 3 days (range 1-21 days). The pancreatitis was classified as mild in 10 cases, moderate in 3, and severe in one; one death (proximate cause, pulmonary embolism) occurred after the development of pancreatitis in a patient with multiple comorbid conditions. CONCLUSIONS: EUS-guided FNA of solid pancreatic masses is infrequently associated with acute pancreatitis. The procedure appears to be safe when performed by experienced endosonographers. The frequency of post EUS-guided FNA pancreatitis may be underestimated by retrospective analysis.

Acute Disease↗

PubMed2003

Hepatotoxicity associated with 6-thioguanine therapy for Crohn's disease.

6-Thioguanine (6-TG) is a thiopurine analogue that is closely related to 6-mercaptopurine (6-MP) and azathioprine (AZA). These agents have potent cytotoxic and immunomodulatory effects and are useful in the treatment of a variety of conditions, including inflammatory bowel disease. Both 6-MP and AZA are widely used and are known to cause hepatotoxicity in a proportion of patients. 6-Thioguanine is being increasingly used in the treatment of inflammatory bowel disease but has not been reported to cause liver injury in this context. We describe a case of significant elevation of serum transaminases in a patient treated with 6-TG for a flare of Crohn's disease. We believe the temporal association of the abnormal liver enzymes in this patient, in the absence of other offending agents, argues strongly in favor of 6-TG as a cause of liver enzyme abnormalities. This case highlights the need to monitor liver enzymes in patients treated with 6-TG and identifies the need for additional research focused on the mechanism of thiopurine-induced hepatic injury.

Adult↗

PubMed2003

Colonic pseudo-obstruction: the dilated colon in the ICU.

Acute colonic pseudo-obstruction is a syndrome of massive dilation of the colon without mechanical obstruction that develops in hospitalized patients with serious underlying medical and surgical conditions. Increasing age, cecal diameter, delay in decompression, and status of the bowel significantly influence mortality, which is approximately 40% when ischemia or perforation is present. Evaluation of the markedly distended colon in the intensive care unit setting involves excluding mechanical obstruction and other causes of toxic megacolon such as Clostridium difficile infection, and assessing for signs of ischemia and perforation. The risk of colonic perforation in acute colonic pseudo-obstruction increases when cecal diameter exceeds 12 cm and when the distention has been present for greater than 6 days. Appropriate management includes supportive therapy and selective use of neostigmine and colonoscopy for decompression. Early recognition and management are critical in minimizing complications.

Acute Disease↗