Effects of ischemic conditioning on head and neck free flap oxygenation: a randomized controlled trial

Abstract

Flap failure after microvascular reconstructive surgery is a rare but devastating complication caused by reperfusion injury and tissue hypoperfusion. Remote ischemic conditioning (RIC) provides protection against ischemia/reperfusion injury and reduces tissue infarction. We hypothesized that RIC would enhance flap oxygenation and exert organ-protective effects during head and neck free flap reconstructive surgery. Adult patients undergoing free flap transfer surgery for head and neck cancer were randomized to receive either RIC or sham-RIC during surgery. RIC consisted of four cycles of 5-min ischemia and 5-min reperfusion applied to the upper or lower extremity. The primary endpoint, tissue oxygen saturation of the flap, was measured by near-infrared spectroscopy on the first postoperative day. Organ-protective effects of RIC were evaluated with infarct size of rat hearts perfused with plasma dialysate from patients received RIC or sham-RIC. Between April 2018 and July 2019, 50 patients were randomized (each n = 25) and 46 were analyzed in the RIC (n = 23) or sham-RIC (n = 23) groups. Tissue oxygen saturation of the flap was similar between the groups (85 ± 12% vs 83 ± 9% in the RIC vs sham-RIC groups; P = 0.471). Myocardial infarct size after treatment of plasma dialysate was significantly reduced in the RIC group (44 ± 7% to 26 ± 6%; P = 0.018) compared to the sham-RIC group (42 ± 6% to 37 ± 7%; P = 0.388). RIC did not improve tissue oxygenation of the transferred free flap in head and neck cancer reconstructive surgery. However, there was evidence of organ-protective effects of RIC in experimental models.Trial registration: Registry number of ClinicalTrials.gov: NCT03474952.

Smoking and Flap Survival: A Comprehensive Systematic Review

“…Min, SH et al (2022) 9 showed Remote ischemic conditioning (RIC) did not improve flap tissue oxygenation after head and neck cancer reconstructive surgery. There was evidence of a myocardial-protective role of RIC in the ex vivo I/R injury model using plasma dialysate from patients.…”

Free Flap Perfusion in Microvascular Head and Neck Reconstruction: Influence of the Number of Ischemia Intervals and Ischemia Duration—A Retrospective Study

“… 4 - 6 Although flap perfusion is critical for flap viability and survival and is used as a parameter for flap monitoring, it remains unknown whether the number of ischemia intervals and the duration of ischemia influence microvascular free flap perfusion. 13 - 15 , 19 - 21 Such information may improve the understanding of microvascular free flap perfusion in general, provide potential guidance for controlling the number of ischemia intervals and the ischemia duration, and support the accurate interpretation of flap perfusion measurements in the context of flap monitoring.…”

Oxygen Therapy Against Changes in Oxygen Saturation Levels in Patients with Head Injuries

“…Ini pada evaluasi tindakan pasien rawat jalan berusia sembilan belas tahun berusia dua puluh tahun mengalami perubahan hemodinamik dan kesadaran, pasien berusia enam puluh tahun meninggal [20]. RIC akan meningkatkan oksigenasi flap dan memberikan efek pelindung organ selama operasi rekonstruksi flap bebas kepala dan leher [21].…”