Gastrointestinal Nursing.pdf

Diagnostic Procedures and Tests in Gastroenterology 143ProctosigmoidoscopyProctosigmoidoscopy is an examination of the rectum and sigmoid colon usinga proctoscope, a rigid tube with a detachable, disposable end which is used forone patient only and then discarded. The proctoscope is 25–30 cm in lengthand approximately 1.5 cm in diameter. Proctosigmoidoscopy gives valuableinformation about the anal canal and rectum, but as the instrument is rigid itcannot be used to view above the splenic flexure. Indications for proctosigmoidoscopyinclude:• melaena• persistent diarrhoea• passage of mucus and pus with stool• bacteriology or histological studies• rectal painPreparation involves a hypertonic phosphate enema on the morning of theprocedure, to clean out the large bowel. Sedation is rarely required forproctosigmoidoscopy. The patient is asked to lie on his or her left side withknees drawn up to the chest, the scope is gently inserted, the obturator isremoved, and air is pumped through the protosigmoidoscope to inflate therectum. The examiner will note the colour and friability of the rectal mucosa,and bleeding sites and ulcers. Throughout the procedure the nurse shouldmonitor the patient’s vital signs, abdominal distension, pain tolerance and thecondition of the skin.Flexible sigmoidoscopyFlexible sigmoidoscopy employs a flexible instrument to examine therectum, sigmoid and a variable length of more proximal colon. The flexiblesigmoidoscope measures up to 65 cm in length and its flexibility allowsthe endoscopist to reach the descending colon in up to 80% of patients. Oneadditional benefit of flexible sigmoidoscopy is that it is better tolerated thanrigid protosigmoidoscopy in many patients. Flexible sigmoidoscopy is generallyindicated for:• Screening of asymptomatic patients at risk of colonic cancer.• Evaluation of suspected distal colonic disease when there is no indicationfor colonoscopy.• Evaluation of the colon in conjunction with radiological examinations.• Patients with a family history of colorectal cancer.• Flexible sigmoidoscopy is generally not indicated when colonoscopy isindicated.