A prospective assessment of renal impairment after preparation for colonoscopy: oral sodium phosphate appears to be safe in well-hydrated subjects with normal renal status

BACKGROUND

The outcome of colonoscopy is highly dependent upon the quality of bowel cleansing prior to the procedure. Oral sodium phosphate solutions (OSPS) or preparations containing polyethylene glycol (PEG) are generally employed. However, the safety of administering OSPS prior to colonoscopy has been questioned because of the potential for renal failure.

AIM

To compare rates of renal failure after OSPS and PEG in a randomized, prospective trial and to assess the quality of colonoscopy after these two bowel preparations.

METHODS

Subjects with eGFR >or= 60 ml/min/1.73 m(2) and expressed willingness to adhere to hydration recommendations were randomized to OSPS or PEG solutions. Renal function was assessed 1 week prior to, immediately prior to, and 1 week after colonoscopy.

RESULTS

No subject had acute kidney failure after OSPS or PEG. OSPS was associated with significant increases in the serum phosphate and sodium levels and significant decreases in the calcium and potassium levels. These values returned to normal limits in all subjects by 1 week after colonoscopy. The quality of colonic cleansing was superior after OSPS than after PEG (Ottawa score 2.5 +/- 2.2 vs. 3.5 +/- 2.3, respectively, P < 0.05). The detection of one or more adenomatous polyps was higher after OSPS than after PEG.

CONCLUSIONS

Renal failure was not detected after the use of OSPS for colonoscopy preparation in subjects with recently documented normal renal function who were able to consume the required amounts of water after each dose. However, based on the number of subjects studied, the theoretical risk of this complication is still between 0 and 6.3%. Thus, it is appreciated that only a very large prospective trial would have yielded a more accurate estimate of the likelihood of renal compromise after OSPS. Despite this caveat, OSPS has advantages over PEG in terms of the adequacy of colonic visualization and the number of polyps detected.

Clinical trial: the efficacy and safety of routine bowel cleansing agents for elective colonoscopy in persons with spinal cord injury - a randomized prospective single-blind study

BACKGROUND

As difficulty with evacuation is a common occurrence in individuals with spinal cord injury, preparation prior to colonoscopy may be suboptimal and, perhaps, more hazardous.

AIM

To assess the safety and efficacy of bowel cleansing regimens in persons with spinal cord injury.

METHODS

Randomized, prospective, single blind study comparing polyethylene glycol (PEG), oral sodium phosphosoda (OSPS) and combination of both for colonic preparation prior to colonoscopy in subjects with spinal cord injury.

RESULTS

Thirty six subjects with eGFR > or =60 mL/min/1.73 m(2) were randomized to PEG or OSPS or PEG+OSPS. Regardless of bowel preparation employed, >73% of subjects had unacceptable colonic cleansing. No subject in the OSPS preparation group demonstrated a decrease in eGFR or an increase in serum creatinine concentration from the baseline. OSPS and PEG+OSPS preparations caused a transient change in serum potassium, phosphate and calcium concentrations, but no change in electrolytes was noted in the PEG group.

CONCLUSIONS

Neither OSPS alone, PEG alone nor their combination was sufficient to prepare adequately the bowel for colonoscopy in most patients with spinal cord injury. However, administration of OSPS and/or PEG appears to be safe in the spinal cord injury population, provided adequate hydration is provided.

The renal safety of bowel preparations for colonoscopy: a comparative study of oral sodium phosphate solution and polyethylene glycol

BACKGROUND

Rare cases of nephrotoxicity have been reported with oral sodium phosphate solution (OSPS).

AIM

To evaluate whether OSPS is associated with changes in renal function.

METHODS

A chart review performed on 311 patients who had colonoscopy at the James J. Peters VA Medical Centre prepared with either OSPS (n = 157) or polyethylene glycol (PEG) (n = 154). Patients had a baseline serum creatinine <or=1.5 mg/dL. Effect of bowel preparation on the renal function was evaluated by measuring the absolute change in levels of serum creatinine and the proportion of patients who developed a 50% or more increase above their baseline serum creatinine value.

RESULTS

Oral sodium phosphate solution resulted in a slight increase in serum creatinine from 1.0 +/- 0.02 to 1.1 +/- 0.02 mg/dL (P = 0.07) and PEG resulted in a small decrease in serum creatinine from 1.1 +/- 0.02 to 1.0 +/- 0.03 mg/dL (P = 0.03). The absolute change in serum creatinine was slightly higher with OSPS than with PEG (0.04 +/- 0.02 vs. -0.05 +/- 0.02 mg/dL; P = 0.005). However, the proportion of patients who had a >or=50% increase above their baseline creatinine was similar (OSPS vs. PEG, 5% vs. 3%, P = 0.77).

CONCLUSIONS

Oral sodium phosphate solution was associated with a slight increase in serum creatinine, which was not clinically significant. Renal toxicity from OSPS appears to be minimal when used in patients with serum creatinine value <1.5 mg/dL.

Fenoldopam: a new dopamine agonist for the treatment of hypertensive urgencies and emergencies

Fenoldopam is a selective dopamine agonist that is being considered for the parenteral treatment of systemic hypertension. In both an oral and parenteral form, the drug causes peripheral vasodilation by stimulating dopamine-1 adrenergic receptors. Its pharmaco-dynamics are reviewed in this article, along with the clinical experiences in patients with hypertensive urgencies and emergencies. Intravenous fenoldopam may provide advantages over sodium nitroprusside because it can induce both a diuresis and natriuresis, is not light sensitive, and is not associated with cyanide toxicity. There is no evidence for rebound hypertension after discontinuation of fenoldopam influsion.