What is the role of a water enema in maintaining bowel health?

From the Guidelines

Water enemas play a crucial role in maintaining bowel health, particularly in patients with constipation, by distending the rectum, moistening stools, and softening faeces with minimal irritating effects on the rectal mucosa.

Key Points

• The use of water enemas, such as normal saline enemas, can help to soften stools and stimulate bowel movements 1.
• Enemas are typically used when oral treatments have failed and can be effective in preventing faecal impaction 1.
• However, enemas should be used with caution, as they can cause adverse effects such as water intoxication, chemical irritation of the mucous membranes, and bleeding complications 1.
• Contraindications to enemas include neutropaenia, thrombocytopaenia, paralytic ileus, intestinal obstruction, and recent colorectal or gynaecological surgery 1.
• The choice of enema type and volume should be individualized based on the patient's specific needs and medical history, and administered by an experienced health professional when necessary 1.
• It is essential to assess the cause and severity of constipation before using enemas and to rule out underlying conditions such as bowel obstruction or hypercalcemia 1.

From the Research

Role of Water Enema in Maintaining Bowel Health

• The use of water enemas for bowel preparation and constipation relief has been studied in various research papers 2, 3, 4, 5, 6.
• A study published in 2013 found that enemas can be effective in treating acute constipation, but may cause serious adverse events such as perforation or metabolic derangement 2.
• Another study published in 2021 reported a previously unreported complication of chronic enema use, known as enema-induced spastic left colon syndrome, which can cause severe abdominal pain and colon dilatation 3.
• Research has also compared the effectiveness and side effects of different types of enema solutions, including soapsuds, tap water, and polyethylene glycol-electrolyte solution 4.
• A study published in 1990 found that at least three tap-water enemas should be given before a double-contrast enema to ensure good technical quality 5.
• Additionally, a study published in 2011 compared the use of water enema and sodium phosphate for bowel preparation before colonoscopy, and found that sodium phosphate had better tolerability, efficacy, and a shorter mean duration for the procedure 6.

Adverse Events and Complications

• The use of water enemas has been associated with adverse events such as perforation, hyperphosphatemia, and sepsis, particularly in the elderly 2.
• Chronic enema use has also been linked to enema-induced spastic left colon syndrome, which can cause severe abdominal pain and colon dilatation 3.
• Rectal biopsies have shown surface epithelium loss after soapsuds and tap water enemas, but not after polyethylene glycol-electrolyte solution enemas 4.

Effectiveness of Water Enemas

• Water enemas have been found to be effective in treating acute constipation, but may not be as effective as other bowel preparation methods such as sodium phosphate 2, 6.
• The use of water enemas has been shown to produce significantly greater returns than polyethylene glycol-electrolyte solution enemas, but may also be more uncomfortable 4.