Comparison of the effects of the inhalation and spinal anesthesia on microcurcilation in experimental rat musculocutaneous flap models

ABSTRACT Objective: To examine the effects of spinal anesthesia on microcirculation, applied in different musculocutaneous flaps which was told to effect flap microcirculation positively in postoperative period. Method: 35 rats separated into five groups. First group was control group with no ischemia. TRAM flap was elevated under inhalation anesthesia in second group, TRAM flap was elevated under spinal anesthesia in third group, gluteus maximus muscle flap was elevated under inhalation anesthesia in fourth group, and gluteus maximus flap was elevated under spinal anesthesia in fifth group. Cutaneous O2 saturation was measured on 0th, 7th, 14th, and 28th days in all groups. All rats were sacrificed by taking intracardiac blood samples at the end of the experiment. MDA, TAL, and TOL values of the blood samples were determined. Samples were obtained from flap tissues for histhopathologic examination. Areas of edema, congestion, necrosis, inflammation, bleeding, hyalinization, nuclear centralization, and fibrosis were evaluated in histhopathologic evaluation and results were classified as (+), (++), (+++), (++++) and grading was done. Results were evaluated statistically. Results: In biochemical evaluation, MDA values were determined as 1-2; ( p=0.002), 1-3; ( p=0.004), 1-4; ( p=0.001), 2-5; ( p=0.002), 3-5; ( p=0.005), 4-5; ( p=0.002). There were significant difference and MDA values were found to be elevated significantly in TRAM flap elevated groups both under spinal and inhalation anesthesia. MDA values were found to be significantly elevated in only gluteus maximus elevated group under inhalation anesthesia, among the gluteus maximus elevated groups. TAL values were significantly elevated in TRAM flap elevated group under inhalation anesthesia and gluteus maximus elevated group under spinal anesthesia. Despite the use of same anesthetic technique in both flap elevation procedures outcomes were different; TAL values were significantly higher in TRAM flap elevated group under inhalation anesthesia compared to gluteus maximus flap elevated group under same anesthetic technique. TAL values were significantly higher in gluteus maximus flap elevated group among the spinal anesthesia applied groups. Another significant difference was detected between group 4 and 5. TAL values were significantly higher in gluteus maximus flap elevated group under spinal anesthesia compared to inhalation anesthesia applied group with the same flap elevated. (1-2; p=0.024, 1-5; p<0.001, 2-4; p=0.023, 3-5; p=0.002, 4-5; p<0.001). Significant difference was detected between group 2 and 4, based on statistical analysis of TOL values. TOL values were significantly higher in TRAM flap elevated group under inhalation anesthesia compared to gluteus maximus flap elevated group with the same anesthetic technique applied. Histhopathologic examination and results showed significant difference between control group and both TRAM flap elevated group and an increase in hyalinization in latter groups. Conclusion: In line with the results, it was concluded that anesthetic method affects the microcirculation of the flap; however localization of the flap is also important.