Smoking and microvascular free flap perfusion in head and neck reconstruction: radial free forearm flaps and anterolateral thigh flaps

Abstract

Head and neck reconstruction with microvascular free flaps is frequently performed in smokers. Smoking causes various alterations in the cardiovascular system. The aim of this study was to investigate the effects of smoking on flap perfusion as a critical factor for flap survival. A total of 370 patients reconstructed with a radial free forearm flap (RFFF) or anterolateral thigh flap (ALTF) in the head and neck region between 2011 and 2020 were retrospectively analyzed. Flap perfusion measurements with the O2C tissue oxygen analysis system were compared between nonsmokers, light smokers (< 20 pack-years), and heavy smokers (≥ 20 pack-years). The blood flow was intraoperatively equal in RFFFs (84.5 AU vs. 84.5 AU; p = 0.900) and increased in ALTFs (80.5 AU vs. 56.5 AU; p = 0.001) and postoperatively increased in RFFFs (114.0 AU vs. 86.0 AU; p = 0.035) and similar in ALTFs (70.5 AU vs. 71.0 AU; p = 0.856) in heavy smokers compared to nonsmokers. The flap survival rate was similar in nonsmokers, light smokers, and heavy smokers (97.3%, 98.4%, and 100.0%). Smoking partially increases rather than decreases microvascular free flap perfusion, which may contribute to similar flap survival rates in smokers and nonsmokers.

Figure 1

Intraoperative perfusion measurement. Each dot represents an individual blood flow (AU) with median (center line) and 1. and 3. quartile (upper and lower lines) for intraoperative measurement (separately described for the group of nonsmokers (NS), the group of light smokers (LS) and the group of heavy smokers (HS)); p values corresponding to testing for differences with Mann Whitney test; significant p values are bold (*p = 0.006 with adjustment for sex, age, BMI, diabetes, mean arterial pressure and catecholamine dose); RFFF radial free forearm flap, ALTF anterolateral thigh flap, NS nonsmokers, LS light smokers, HS heavy smokers, AU  arbitrary units.

Figure 2

Postoperative perfusion measurement. Each dot represents an individual blood flow (AU) with median (center line) and 1. and 3. quartile (upper and lower lines) for postoperative measurement (separately described for the group of nonsmokers (NS), the group of light smokers (LS) and the group of heavy smokers (HS)); p values corresponding to testing for differences with Mann Whitney test; significant p values are bold (*p = 0.046 with adjustment for sex, age, BMI, diabetes, mean arterial pressure and catecholamine dose); RFFF radial free forearm flap, ALTF anterolateral thigh flap, NS nonsmokers, LS light smokers, HS heavy smokers, AU arbitrary units.