Ask The Expert: Question Archive

Question:
Why does a patient’s hematocrit level usually drop more on post-op day 2 than the day after surgery?

NAAC Expert Answer:
During surgery, most patients receive more intravenous fluids than they would normally get during hospitalization outside of the operating room. Some of this fluid will be excreted as urine, but some will be retained in the tissues (water retention). The retained water gets re-absorbed into the patient’s blood stream on the second, third and sometimes fourth days after surgery. This extra fluid in the circulatory system can dilute the level of red blood cells and may artificially lower the hematocrit level. Once the re-absorbed fluid is urinated, the hematocrit level should return to an accurate level.

Last Updated: November 19, 2009