Acute hypoferremia following cardiac surgery.

Serum iron concentration, temperature, white blood count, and weight were reviewed throughout hospitalization in 13 patients who underwent open-heart surgery for valvular replacement and 43 who required coronary artery bypass grafting. Serum iron concentration climbed from an admission average of 91.1 micrograms/100 ml +/- 44.0 to 124.3 micrograms/ml +/- 40 within 12 hours of surgery and then rapidly dropped to 29.0 micrograms/100 ml +/- 20.1 within 18 hours of surgery. Serum iron levels remained less than one half of admission values throughout hospitalization (2 weeks). Temperature increased from 98.6 F +/- 0.5 before surgery to 101.1 F +/- the night of surgery, remaining mildly elevated until 14 days following surgery. White blood count jumped from admission levels of 7.1 X 10(3) +/- 1.8 to 15.2 X 10(3) +/- 5.8 within 6 hours of operation. Preoperative levels were again reached 5 days following operation. Patient weights averaged 73.9 kg +/- 14.6 on admission increasing to 78.6 kg +/- 10.4 on the day following surgery. Only hypoferremia persisted beyond discharge into the anabolic phase of recovery. Stress-induced hypoferremia following operation runs a different time course than fewer, leukocytosis, or weight gain and thus must be mediated by a different mechanism.