Effect of bowel preparation with oral sodium phosphate on serum potassium level in patients undergoing colonoscopy under IV anesthesia.
OBJECTIVE
To determine the effect of oral sodium phosphate solution, as a colon preparation agent, on the serum potassium level in patients undergoing colonoscopy under IV anesthesia.


METHODS
Patients set to undergo elective colonoscopy under IV anesthesia (propofol infusion) were recruited to participate in the present study during the period between October 2008 and January 2009. All patients had normal serum potassium level prior to colon preparation, and all ingested 90 ml of sodium phosphate solution one day before colonoscopy. Blood samples for post preparation potassium level determination were taken immediately before administering IV propofol. Baseline data including age, gender, diagnosis, indication for colonoscopy, underlying illness, concurrent medications and serum potassium and creatinine levels were recorded The serum potassium levels were compared before and after colon preparation, and potentially important baseline risk factors for low potassium levels after colon preparation were determined.


RESULTS
In 48 patients, there was a 0.57 mmol/L (from 4.11 to 3.54 mmol/L) average reduction in the serum potassium level after colon preparation. There were no significant adverse events during colonoscopy. No significant risk factors were identified on multivariable linear regression analysis.


CONCLUSIONS
There was a mild reduction in serum potassium level after colon preparation with oral sodium phosphate solution, which was probably not clinically significant. Prophylactic potassium supplement or routine serum potassium monitoring after oral sodium phosphate colon preparation did not seem to be necessary for this group of patients.
Singhatas
Pongsasit
P
Department of Surgery, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Sangdee
Nakkanan
N
Kositchaiwat
Savit
S
Sumboonanonda
Kanit
K
Suwanthanma
Weerapat
W
Sumritpradit
Preeda
P
Lertsithichai
Panuwat
P
D000284:Administration, Oral; D000771:Anesthesia, Intravenous; D018686:Anesthetics, Intravenous; D002400:Cathartics / Q000008:administration & dosage*; D003113:Colonoscopy / Q000379:methods*; D016001:Confidence Intervals; D017558:Elective Surgical Procedures; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010710:Phosphates / Q000008:administration & dosage*; D011188:Potassium / Q000097:blood*; D011300:Preoperative Care / Q000009:adverse effects / Q000379:methods* / Q000592:standards; D015742:Propofol; D012307:Risk Factors
D018686:Anesthetics, Intravenous; D002400:Cathartics; D010710:Phosphates; D011188:Potassium; C018279:sodium phosphate; D015742:Propofol