The Effect of Ischemic Preconditioning on Postoperative Pain After Total Knee Arthroplasty, a Randomized, Controlled Trial

During knee surgery your surgeon routinely uses a device called a tourniquet that allows us
to temporarily cut of blood supply to the site of surgery. This helps to reduce blood loss
and improves operating conditions. When allowing blood back into your leg at the end of the
procedure, debris (bone, fat, tissue breakdown products and cement from the surgery) gets
washed out and gains access to the rest of your body. In the vast majority of cases this
event bares no major clinical consequences, but can rarely result in signs of inflammation
of various body systems. Patients with evidence of impaired organ system function such as
pre-existing lung and heart disease may be more vulnerable. Previous studies suggest that
cutting off the blood supply for a short period of time just before a prolonged episode,
could lead to a decrease in the extent of tissue breakdown products in this extremity and
may thus be associated with a decrease in the inflammation of other organ systems. We
propose to study this theory in knee surgery patients by looking at levels of markers of
inflammation present in the blood before and after surgery.

Inclusion Criteria:

- All patients undergoing primary total knee arthroplasty

Exclusion Criteria:

- Patients who chronically use narcotics (<1 month).

- Patients with contraindications (severe peripheral vascular disease, presence of
femoral-popliteal bypass grafts, etc.) or no plan for tourniquet use as determined by
the clinical care team.

- Patients who are on corticosteroids prior to their surgery