An enema is the insertion of a solution into the rectum and lower intestine given to remove feces when an individual is constipated or impacted or in preparation for an examination or surgery, or to give drugs or anesthetic agents.The rectal tube used to give the enema should be smooth and flexible to decrease the possibility of damage to the lining of the rectum. Tap water is commonly used for adults but should not be used for infants because of the dangerof electrolyte (substance that conducts electric current within the body andis essential for sustaining life) imbalance. The colon absorbs water, and repeated tap water enemas can cause cardiovascular overload and electrolyte imbalance. Repeated saline enemas can cause increased absorption of fluid and electrolytes into the bloodstream, resulting in overload. Individuals receivingfrequent enemas should be observed for overload symptoms that include dizziness, sweating, or vomiting. Soap suds and saline used to clean enemas can irritate the lining of the bowel, with repeated use or a solution that is too strong. Only white soap not previously used should be used. The commercially prepared castile soap is preferred, in a concentration no greater than 5 cc soap to 1,000 cc of water.
Cleansing enemas stimulate bowel activity by irritating the lower bowel, andby stretching with the volume of fluid given. When the enema is given, the individual is usually on the left side-lying position, which facilitates absorption of fluid. The length of time it takes to administer an enema depends onthe amount of fluid to be absorbed. This varies depending on the age and sizeof the person receiving the enema, however, general guidelines would be: 250cc or less for an infant, 500 ml or less for a toddler or preschooler, 500-1,000 cc for a school-aged child, and 750-1,000 cc for an adult. A high enema,given to cleanse as much of the large bowel as possible, is usually administered at higher pressure and with larger volume (1,000 cc), and the individualchanges position several times in order for the fluid to flow up into the bowel. A low enema, intended to cleanse only the lower bowel, is administered at lower pressure, using about 500 cc. of fluid. Oil retention enemas lubricate the rectum and lower bowel, and soften the stool. For adults, about 150-200cc of oil is instilled, while in small children, 75-150 cc of oil is enough.Salad oil or liquid petrolatum are commonly used at a temperature of 91°F (32.8°C). There are also commercially prepared oil retention enemas. The oil is usually retained for one to three hours before it is expelled.
The rectal tube used for infusion of the solution, usually made of rubber orplastic, has two or more openings at the end through which the solution can flow into the bowel. The distance to which the tube must be inserted is dependent upon the age and size of the patient. To prepare an enema, the solution is measured, mixed, and warmed. Afterward, if necessary, a specimen is collected for diagnostic evaluation. Enemas should be used only as a last resort fortreatment of constipation and with a doctor's recommendation. Enemas shouldnot be given to individuals who have recently had colon or rectal surgery, aheart attack, or who suffer from an unknown abdominal condition or an irregular heartbeat.