<< Back to the abstract archive
Ex Vivo Normothermic Preservation (EVNP) of Porcine Superior Epigastric Artery Perforator Flap
Payam Sadeghi, Abigail Meyers, Varun Kopparthy, Ryan Khalaf, Jose Reyes, R'ay Fodor, Robert C Clark, Francis Papay, Antonio Rampazzo, Bahar Bassiri Gharb
Plastic Surgery Department, Cleveland Clinic
2022-01-15
Presenter: Payam Sadeghi, MD
Affidavit:
All the authors contributed to the study as the following:
Payam Sadeghi: The acquisition, analysis and interpretation of data, drafted and provided critical revision of the abstract
Abigail Meyers: The analysis of data, provided critical revision of the abstract
Varun Kopparthy: acquisition of data, study design participation
Ryan Khalaf, Jose Reyes, R'ay Fodor, Robert C Clark: helped in acquisition of data
Francis Papay, Antonio Rampazzo, Bahar Bassiri Gharb: conception and design of the study
Director Name: Bahar Bassiri Gharb
Author Category: Fellow Plastic Surgery
Presentation Category: Basic Science Research
Abstract Category: General Reconstruction
PURPOSE: In vessel-depleted patients, free flap reconstruction is challenging. We aimed to develop a protocol for EVNP to maintain flaps in near physiologic conditions.
METHODS: Ten flaps based on superior epigastric pedicles were procured from Yorkshire pigs. Flaps were preserved using the flap preservation machine (FPM, n=5), or at 4°C (control) for 12h (n=5). Perfusate contained a colloid blood-like solution. Outcome measures, including perfusate dynamics, temperature, gases, metabolites and electrolytes, flap weight, histology (Hematoxylin and Eosin) and perfusion (indocyanine Green (ICG) angiography) were monitored and evaluated using Pearson correlations and paired t-tests.
RESULTS: Eight flaps were included in analysis because bacterial colonization of the first flap's perfusate precluded reliable measurements. Mean arterial pressure (50±3mmHg) remained stable during EVNP (r=0.25, p=0.41). Mean perfusate and flap temperatures were 31±1°C and 28±1°C, respectively. PaO2 was 461±72mmHg, pH 7.37±0.01, and arterial glucose 4.6±0.3mmol/L. Venous lactate was 4.9±0.9mmol/L and stable (TP0 4.8±0.8mmol/L vs. TP12 5.3±1.6mmol/L, p=0.34). Creatine kinase increased over time (TP0 1137±739U/L vs. TP12 6340±1606U/L; r=0.97, p=0.03). Venous methemoglobin was 31.94±10.1%, and increased (r=0.96, p<0.0001). Potassium remained in a physiologic range (4.0±0.2mEq/L), while sodium was slightly elevated (159±1mEq/L). Flap weight did not increase during perfusion (TP0 214±52g vs. TP12 223±53g, p=0.42) or in controls (TP0 106±16g vs. TP12 104±17g, p=0.43). H&E of perfused skin biopsies revealed no damage. However, superficial vascular congestion was detected in one TP12 control. Perfusion TP12 ICG angiography revealed well-perfused flaps with regional differences.
CONCLUSION: The FPM preserved flaps for 12 hours. Physiologic parameters were maintained without development of edema.
