NEW YORK (Reuters Health) – Sodium phosphate enemas, even in standard doses, may lead to severe metabolic disorders and death in elderly patients, warn clinicians from Israel in a paper this month in Archives of Internal Medicine.

“Their use should be limited to low-risk patients only,” advise Dr. Yaacov Ori from Rabin Medical Center, Petah-Tikva and colleagues.

At their institution, they encountered 11 patients (8 in 2009-2011) who experienced severe complications after receiving sodium phosphate-containing Fleet enemas for constipation (10 patients) or in preparation for proctoscopy (1 patient). Three of the patients received 500 to 798 mL, and 8 received a standard 250-mL dose.

There were six women and five men. Their mean age was 80 years (range, 61-89 years). “Most presented within 24 hours with hypotension and volume depletion, extreme hyperphosphatemia (phosphorus level, 5.3-45.0 mg/dL), and severe hypocalcemia (calcium level, 2.0-8.7 mg/dL),” the authors say.

Most patients also developed hypernatremia and hypokalemia following the enema and all had acute renal failure. Before receiving the enema, renal function was normal in four patients (eGFR > 60 mL/min/1.73m²) and moderately impaired in the other seven (eGFR 25-57 mL/min/1.73m²).

Two patients required urgent hemodialysis and five patients died (45%); three of the six survivors (50%) experienced general functional decline and required prolonged hospital stays, the authors note.

The one patient that was autopsied had calcium-phosphate deposition within the renal tubular lumens.

Dr. Ori and colleagues point out that phosphate-containing enemas are widely used and elderly patients often receive repeated enemas. They also note that the true incidence of complications associated with Fleet enemas is unknown and it’s likely that some problems go undiagnosed.

They advise that “any elderly patient with an atonic bowel for whatever reason and a reduced GFR should not receive a phosphate-containing enema.”

The authors note that an educational campaign at Rabin Medical Center regarding the potential dangers of Fleet enemas in elderly has led to a 96% reduction in their use.

SOURCE:

Arch Intern Med 2012;172:263-265.