The role of age in determining the effects of lipo-PGE1 infusion on immediate arterial maximal flow velocity in patients with diabetes undergoing free flap surgery for lower extremity reconstruction: A prospective observational study.

[BACKGROUND] Diabetes mellitus may have a negative effect on free flap perfusion in patients undergoing reconstructive surgery. Little is known of the effects of lipo-prostaglandin E1 (lipo-PGE1) on flap blood flow in diabetes. This study investigated the effects of lipo-PGE1 on maximal blood flow velocity of the free flap arterial pedicle in patients with diabetes.

[METHODS] This prospective observational study assessed maximal blood flow velocity in the arterial pedicle before and 30 min after infusion of 0.4 μg/h lipo-PGE1 in 40 patients with diabetes who received a free flap for lower extremity reconstruction. Multivariate logistic regression analysis was performed to determine whether age, hemoglobin A1c concentration, duration of diabetes, and flap type were significantly associated with increased maximal blood flow velocity after lipo-PGE1 infusion or not.

[RESULTS] The maximal blood flow velocity of the free flap did not differ significantly before and 30 min after lipo-PGE1 infusion. Multivariate logistic regression analysis showed that age <65 years was the only independent factor associated with increased maximal blood flow velocity after lipo-PGE1 infusion (odds ratio = 5.344; p = 0.022).

[CONCLUSION] Assessments of all patients with diabetes undergoing free flap surgery, when age was not taken into consideration, found that lipo-PGE1 did not significantly increase the maximal blood flow velocity of the free flap arterial pedicle. However, when age was taken into consideration, lipo-PGE1 increased blood flow velocity in patients <65 years old, suggesting that age influences the effect of lipo-PGE1 on the blood flow velocity.