Potassium supplements prevent serious hypokalaemia in colon cleansing.
The association between colonic cleansing and hypokalaemia was studied prospectively by monitoring the serum potassium levels in four groups of patients: groups 1 (55 patients), 2 (72 patients), and 3 (97 patients) received the same 2-day preparation of 15 g magnesium sulphate and 10 mg bisacodyl twice daily; group 4 (96 patients) received a 1-day preparation of 2.4 mg sennoside per kg of bodyweight. Groups 1 and 2 were on diuretics, but only group 2 received potassium supplementation. Serum potassium levels were measured before and after bowel preparation. Hypokalaemia was present prior to cleansing in six (11%), and after cleansing in 20 (36%) of the 55 patients in the group 1 patients on diuretics but without potassium supplements. There was, after cleansing, no significant fall in serum potassium in the group 2 patients on diuretics who received potassium supplements. No hyperkalaemia resulted from supplementation. A significant fall of the mean level of serum potassium occurred in patients in both group 3 (2-day-preparation) and group 4 (1-day-preparation). We conclude that both 1 day and 2 days of cleansing with cathartics may result in a significant fall in serum potassium, which can be prevented by oral potassium supplements. Potassium supplements (three times a day 15 ml of potassium chloride with 0.9 mmol K per ml during the preparation) in patients on diuretics may be prudent to avoid the risk of cardiac arrhythmia.
Ritsema
G H
GH
Department of Radiology, St Clara Hospital, Rotterdam, The Netherlands.
Eilers
G
G
D000368:Aged; D000880:Anthraquinones; D001466:Barium Sulfate; D001726:Bisacodyl / Q000009:adverse effects; D002400:Cathartics / Q000009:adverse effects*; D004347:Drug Interactions; D004733:Enema; D006801:Humans; D007008:Hypokalemia / Q000139:chemically induced / Q000517:prevention & control*; D008278:Magnesium Sulfate / Q000009:adverse effects; D011189:Potassium Chloride / Q000627:therapeutic use*; D011446:Prospective Studies; D012676:Senna Extract; D000081226:Sennosides
D000880:Anthraquinones; D002400:Cathartics; D000081226:Sennosides; D001726:Bisacodyl; D001466:Barium Sulfate; D011189:Potassium Chloride; D008278:Magnesium Sulfate; D012676:Senna Extract