Question: My boss recently had blood drawn for surgery and was told he had "thick blood". Can you offer any information on this phenomenon, diagnosis, or remedies?

Dr. Hibberd's Answer:

As a medical professional, I do not use the term "thick blood." Some doctors use this term to explain why they are placing their patients on medicines to “thin" their blood. Some blood “thinners" (such as aspirin, Plavix) actually delay or inhibit platelet function prolonging the time to form a platelet plug while others affect the coagulation time and delay the coagulation process causing prolonged bleeding (such as heparin and coumadin).

To evaluate this condition, first check the complete blood count for abnormalities that may affect blood flow (such as excessive numbers of red blood cells as in polycythemia, or abnormalities of red blood cell form or structure). Our blood flow (often mistakenly referred to as blood thickness) may be affected by local problems with blood vessels as well as abnormalities of blood components.

Excessive coagulation may cause blood function to slow as well as platelet disorders where the numbers of platelets are elevated. Sometimes the appearance of slow flow on blood draw has nothing to do with blood problems, and may be related to a local circulatory disorder or simply related to the size needle used to sample your blood.

Increased tendency for slow flow can be seen with tumor conditions, as well as thrombotic (tendency to clot) disorders, and other conditions that may not be apparent until looked for.

When told one has "thick blood," the first question should be, “Why?” One needs more information to qualify its significance, if any, to one’s health. Then ask what can be done to modify this. Finally, ask if this condition is associated with any underlying medical conditions and whether one is at increased risk for medical problems in the future.
If unsure, or your explanation is not complete, request a referral to a hematologist (medical doctor specializing in disorders of the blood) for a second opinion.