Transfusion criteria in free flap surgery

Area of Science:

• Plastic Surgery
• Surgical Oncology
• Anesthesiology

Background:

• Maintaining adequate hematocrit is crucial in free flap reconstruction.
• Current practice often involves transfusing patients with hematocrit levels above 30%.
• Blood transfusions carry risks of infectious and noninfectious complications.

Purpose of the Study:

• To evaluate the safety and efficacy of lowering the postoperative transfusion trigger to 25% hematocrit.
• To determine if a lower hematocrit threshold increases flap-related complications.
• To assess the impact on blood transfusion rates in free flap surgery.

Main Methods:

• An observational cohort study was conducted at a tertiary care center.
• Two groups of patients undergoing free tissue transfer were compared based on transfusion triggers: <30% vs. <25% hematocrit.
• Outcomes analyzed included flap complications, length of stay, transfusion volume, and lowest postoperative hematocrit.

Main Results:

• The group with a <25% hematocrit trigger had significantly lower mean postoperative hematocrit (26.6% vs. 28.4%) and received fewer blood units (1.47 vs. 2.11).
• Complication rates were similar between groups, with no significant difference in flap loss (2.3% vs. 6.7%).
• Higher rates of fistula and respiratory failure were observed in the <30% hematocrit group.

Conclusions:

• A postoperative transfusion trigger of <25% hematocrit is safe for free flap surgery.
• Lowering the transfusion threshold effectively reduces blood usage without compromising flap outcomes.
• This strategy minimizes unnecessary transfusions and associated risks in free flap reconstruction.