Sodium phosphate enemas are relatively safe for hospitalized patients, according to a new study published online in the QJM.
“Sodium phosphate enemas do not seem to worsen mild to moderate renal failure, nor are they associated with hyperphosphatemia or hyperkalemia in patients hospitalized in internal medicine departments,” lead investigator Gad Segal, MD, of Chaim Sheba Medical Center in Ramat Gan, Israel, told Renal & Urology News. “Phosphate enemas are safe as long as patients are well hydrated.”
In a retrospective study, Dr Segal and his team compared serum creatinine and electrolyte levels among inpatients at their institution from 2007 to 2016 treated and not treated with a single sodium phosphate fleet enema (3 mmol/mL). The 412 total patients were matched by age; gender; baseline creatinine; status with regard to nephrotoxic or cardiorenal syndromes (e.g., diabetes, congestive heart failure, and arterial hypertension); and medications that potentially impact glomerular filtration rate (e.g., angiotensin converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone receptor antagonists).
Blood test results showed no significant differences in maximum levels of creatinine, phosphorus, potassium, and calcium between treated and untreated patients following sodium phosphate enema administration. Maximum creatinine was 1.05 vs 1.04 mg/dL; phosphorus 3.3 vs 3.48 mg/dL; potassium 4.1 vs 4.1 meq/L; and calcium 8.7 vs 8.8 mg/dL, respectively. Subgroup analyses by baseline creatinine (above 1.5 mg/dL and above 2 mg/dL) showed the same pattern.
Previous case reports had raised concerns that sodium phosphate enemas might lead to renal decline. But none of those studies were controlled, the investigators pointed out. “Physician-monitored hydration may have eliminated some of the potential deleterious effects of sodium phosphate enemas found in previous studies,” Dr Segal stated.
Dagan A, Stein GY, Winter S, et al. Sodium phosphate enemas do not worsen renal function amongst hospitalized patients with mild to moderate renal failure. A matched, case-control study. QJM 2017; published online ahead of print. doi: doi.org/10.1093/qjmed/hcx165