Percutaneous sonography-guided fine needle aspiration biopsy of colonoscopic biopsy-negative colonic lesions.

BACKGROUND: Pre-operative tissue diagnosis with colonoscopy is not always possible in patients with colonic lesions. OBJECTIVE: To study the usefulness and efficacy of percutaneous ultrasound-guided aspiration biopsy of colonic lesions. METHODS: Fifty consecutive patients with colonic lesions in whom colonoscopic brush cytology and biopsy were either negative or the lesion was not accessible on colonoscopy on two attempts, underwent percutaneous ultrasound-guided fine-needle aspiration biopsy. The results were compared with surgical findings. RESULTS: Fine-needle aspiration biopsy revealed adenocarcinoma in 40 patients; one had lymphoma, 2 had tuberculosis, 2 had abscess and 5 patients had negative aspiration. Forty-eight patients (excluding 2 with tuberculosis) underwent laparotomy and the diagnoses on aspiration biopsy were confirmed. Of the 5 negative aspirations, 3 had adenocarcinoma, one had tuberculosis and one intussusception. Thus, we had sensitivity of 91.8%, specificity of 100%, predictive value of positive results 100%, predictive value of negative results 20%, and percentage of false negative results 8.1%. Two patients developed complications--hemorrhage into the peritoneum and sepsis due to perforation at the site of aspiration; both survived after surgery. CONCLUSION: Percutaneous ultrasound-guided aspiration biopsy may be attempted for diagnosis of colonic lesions in situations where it may be the only means of obtaining a cytological diagnosis before surgery.

Role of pulse oximetry during nonsedated upper gastrointestinal endoscopic procedures.

BACKGROUND: Although upper gastrointestinal endoscopy is generally a safe procedure, it is known to be associated with arterial oxygen desaturation, resulting in rare serious cardio-pulmonary events. OBJECTIVE: To determine the severity of oxygen desaturation during nonsedated upper gastrointestinal endoscopy and study the effect of various variables on oxygen saturation. METHODS: 126 patients underwent nonsedated upper gastrointestinal endoscopy (82 diagnostic, 44 therapeutic). Arterial oxygen saturation (SaO2) was monitored using a pulse oximeter. RESULTS: Baseline SaO2 was mean (SD) 97.8 (1.8%). It remained > 95% in 60.2% of patients during the procedure, whereas mild oxygen desaturation (SaO2 90%-94%) occurred in 23.7% and severe oxygen desaturation (SaO2 < 90%) occurred in 15.8% of patients. Six patients (4.7%) required supplemental oxygen administration sometime during the procedure. Desaturation occurred in patients undergoing diagnostic and therapeutic procedures but was severe in the latter group (p < 0.002). Patients aged more than 60 years (p < 0.001), hemoglobin < 10 g/dL (p < 0.001), history of smoking (p < 0.001), and underlying chronic obstructive airway disease (p < 0.001) were significantly related to oxygen desaturation. However, on multivariate analysis, no significant correlation was observed with hemoglobin value. CONCLUSION: Therapeutic intervention during nonsedated upper gastrointestinal endoscopy, old age, smokers and chronic obstructive airways disease are independent risk factors for oxygen desaturation. We recommend continuous monitoring of SaO2 in these high-risk patients undergoing upper gastrointestinal endoscopy.