RT Journal
A1 Simbari RD
T1 DIstortion of pbi determination during coronary care
JF Archives of Internal Medicine
JO Archives of Internal Medicine
YR 1969
FD May 1
VO 123
IS 5
SP 597
OP 597
DO 10.1001/archinte.1969.00300150115018
UL http://dx.doi.org/10.1001/archinte.1969.00300150115018
AB To the Editor. 
    —The protein-bound iodine (PBI) determination has become the standard clinical means of thyroid evaluation. The factors known to affect its results have been summarized elsewhere.1,2 The following report of a heretofore unrecognized cause of significant PBI distortion is the result of an investigation conducted because a disproportionate number of patients admitted to the St. Luke's Hospital intensive-care unit (ICU) were found to have elevated serum PBI levels.Over a six-month period, 50% of the PBI values of patients in the ICU were elevated above normal values, in contrast to 7.3% in the other hospital division studied. The Figure reports a study of a patient admitted to the ICU who had daily PBI determinations. This graph reveals a biphasic curve; the first peak occurred soon after the patient's admission to the ICU; the second peak corresponds to the patient's readmission to the ICU after his condition deteriorated