Impact of Postoperative Norepinephrine Administration on Free Flap Flow

Area of Science:

• Plastic Surgery
• Vascular Surgery
• Critical Care Medicine

Background:

• The relationship between blood pressure, vasopressors, and macrocirculation is known, but its effect on microvascular flow in free flap surgery is unclear.
• Optimizing microcirculation is crucial for the success of free flap procedures.

Purpose of the Study:

• To investigate the impact of norepinephrine administration on the microcirculation of free flaps post-surgery.
• To determine if norepinephrine affects key microvascular parameters like blood flow and oxygenation.

Main Methods:

• Prospective monitoring and retrospective analysis of 105 free flap surgery patients in intermediate or intensive care.
• Measurement of microcirculation using laser-doppler flowmetry and white light spectroscopy (Oxygen to See device).
• Multivariate analysis to assess the impact of norepinephrine infusion rates (NIRs) and systolic blood pressure (sBP) on microvascular flow, adjusting for confounders.

Main Results:

• Microvascular flow increased post-anastomosis, while norepinephrine infusion rates decreased and systolic blood pressure remained stable.
• Time post-anastomosis, hemoglobin oxygenation (SO2), relative hemoglobin levels (rHbs), female gender, and absence of prior radiation therapy significantly impacted microvascular flow.
• Norepinephrine infusion rates, systolic blood pressure, smoking status, age, and ASA score did not significantly affect free flap microcirculation.

Conclusions:

• Norepinephrine can be safely used to maintain stable blood pressure in free flap surgery patients without compromising microvascular flow.
• Findings offer valuable guidance for postoperative management strategies in free flap surgery.