A flexible sigmoidoscopy (FS) is a medical procedure used to examine the lower portion of the large intestine, specifically the rectum and the sigmoid colon. This examination utilizes a thin, flexible tube equipped with a light and a camera to screen for abnormal growths, such as polyps, or to diagnose symptoms like rectal bleeding or changes in bowel habits. Many patients are concerned the procedure without sedation will involve intense pain. However, because this is a relatively short examination of the lower bowel, most patients tolerate the procedure well without relaxing or sleep-inducing medication.
Understanding the Sensations During Flexible Sigmoidoscopy
The experience of a non-sedated flexible sigmoidoscopy is generally characterized by discomfort and pressure rather than sharp, acute pain. Most individuals report sensations that resemble intense cramping or a strong urge to have a bowel movement. These feelings are typically manageable and are often intermittent, correlating with specific actions performed by the endoscopist during the examination.
One primary source of discomfort is air insufflation, where gas is pumped into the colon to expand the walls for a clearer view. This inflation creates a feeling of bloating and gas pain as the intestinal walls stretch under pressure. The sensation may be more pronounced as the scope advances and requires space to navigate the natural curves of the lower bowel.
Another factor in the sensation profile is the physical movement of the scope as it is guided through the sigmoid colon. The colon is a muscular tube, and the stretching or sudden bending of its walls by the advancing instrument can trigger muscle spasms and intense cramping. This discomfort is usually brief, subsiding quickly once the scope passes that particular section of the intestine. If the endoscopist needs to remove a small polyp or take a tissue sample (biopsy), the patient typically does not feel this action due to the lack of pain receptors in the mucosal lining of the colon.
Factors that Influence Discomfort Levels
The level of discomfort experienced during the procedure can vary significantly, depending on a combination of physiological and technical variables. A patient’s individual anatomy plays a significant role, particularly the degree of ‘tortuosity,’ or natural winding, of their sigmoid colon. A highly looped or sharply angled colon requires more maneuvering of the scope, which increases the sensation of pressure and cramping as the bowel wall is stretched.
The quality of the patient’s bowel preparation is another important consideration. If the lower bowel is not adequately cleared of stool, the endoscopist must spend more time clearing the view. This increases the duration of the procedure and the time the patient is subjected to insufflation. Patient anxiety also contributes to the physical experience, as tension can cause the abdominal muscles and the colon wall to contract, making the scope’s passage more difficult and intensifying discomfort.
The skill and gentle technique of the endoscopist can substantially affect the patient’s comfort level. Experienced practitioners are adept at minimizing excessive air insufflation and using controlled, slow insertion speeds to navigate the colon’s turns. These technical choices reduce the intensity and duration of uncomfortable sensations.
Techniques for Minimizing Discomfort During the Procedure
Medical staff employ several proactive steps to mitigate the sensations experienced by the non-sedated patient throughout the flexible sigmoidoscopy. One common technique involves asking the patient to change position, often starting on the left side and sometimes moving to the back. These positional adjustments help straighten the colon’s natural loops, allowing the scope to advance more smoothly and with less mechanical pressure on the bowel wall.
Many facilities now use carbon dioxide (\(\text{CO}_2\)) instead of room air for insufflation, which is a major advancement in patient comfort. \(\text{CO}_2\) is absorbed by the body much faster than standard air, significantly reducing the post-procedure bloating and gas pains that can linger for hours. During the examination, the medical team monitors the patient’s verbal and non-verbal reactions.
The endoscopist can immediately adjust the speed of insertion or withdraw the scope slightly in response to acute discomfort. Patients are encouraged to focus on slow, deep breathing techniques throughout the procedure. This focus on controlled respiration helps relax the abdominal musculature, which in turn can lessen the intensity of cramping and reduce overall tension.
The Choice of No Sedation
Choosing to undergo a flexible sigmoidoscopy without sedation involves weighing temporary discomfort against practical advantages. The most immediate benefit is the ability to recover instantly, as there is no medication to wear off. Patients who forego sedation are permitted to drive themselves home immediately following the 15-to-20-minute procedure.
Patients can return to work and resume normal daily activities without the extended observation period required for conscious sedation. This is a major contrast to a sedated procedure, which mandates that a friend or family member drive the patient home and provide supervision for several hours afterward. Because FS examines only the lower third of the large intestine, it is a shorter and generally less involved procedure than a full colonoscopy, making the non-sedated option practical and increasingly popular choice for many individuals.