Monday September 11, 2006
Do you really need IV potassium replacement ?
This is important to know that PO (by mouth) potassium replacement is as effective as IV replacement ans should be use if enteral route is available. Actually, correction of K level could be faster with oral supplementation due to limitation of slow rate needed for IV potassium.
40 meq of PO KCl increases serum K by 0.5 - 0.7 meq/L in 1 - 2 hours, means K level may rise from 3 to 3.5 meq/L with one PO dose of 40 meq KCl elixir.
Sunday September 10, 2006
Q; Which vasopressor can suppress TSH (Thyroid Stimulating Hormone) secretion, and may be a pitfall in TSH screening ?
A; 3 major things in ICU may suppress TSH and may give misleading result.- Dopamine
- High dose steroid
- Caloric deprivation (malnutrition) or NPO status
Word of wisdom is not to check thyroid function test in ICUs as it takes only few hours for patient to ‘abnormalize’ thyroid function test under stress but if clinically indicated send full "Thyroid Function Test” including TSH, Total T3, Total T4, Free T4 and rT3 (reverse T3) - and read your diagnoses carefully preferably with the help of endocrine service or by consulting reference.
Related: Read nice roundup: Sick euthyroid syndrome - Jennifer Best M.D - Harborview Medical Center, seattle, Washington - University of Washington, Div. of General Internal Medicine.
