44 yo F with h/o ESRD on HD and neurosarcoidosis complicated by panhypopituitarism on chronic steroids and thyroid replacement, BIBEMS obtunded. Last seen normal a few hours ago. The patient is hypotensive SBP ~75 and FSBG is undetectably low. The patient’s mental status responds well to D50. She denies exogenous insulin, or other ingestions. Admits to missing HD and to being non-compliant with steroid therapy over the last few days.
There is concern for adrenal crisis, so the patient is given 100mg hydrocortisone, in addition to IV synthroid of for possible myxedema coma. Shortly after HD is initiated, the patient again becomes obtunded. This time her FSBG is normal.
Could one of these medications have been dialyzed out?
The following are some factors that determine the extent to which a drug or molecule is removed by dialysis.
- Molecular weight: In general, larger molecules are easier to dialyze than smaller ones
- Protein Binding: high degree of protein binding, means less free molecules are available for dialysis
- Volume of Distribution: the larger Vd, the more difficult it is to dialyze a drug
- Water Solubility: Lipophilic compounds are more difficult to dialyze.
The following is a link to a list of drugs and the extent dialysis removes them from the body.
According to this list, it is unlikely that HD significantly decreased concentrations of hypocortisone or levothyroxine.