[Characteristics of circulation and microcirculation in healthy people of Han nationality at different altitudes]

Objective: To observe the circulation and microcirculation characteristics of healthy han people in Qinghai at different Guoluo (4 100 m) and Huzhu (2 600 m) and in Shanghai in plain area (4 m). Methods: The 28 healthy han people aged (45.62±10.15) from Guoluo in Qinghai, 27 healthy han people aged (47.25±8.43) from Huzhu in Qinghai and 20 healthy han people aged (43.12±8.28) from Shanghai were divided into three groups: Guoluo group (GL), Huzhu group (HZ) and Shanghai group (SH); Venous blood was collected for routine blood test: red blood cells count(RBC), hemoglobin(HGB), hematocrit(HCT), platelet(PLT); and coagulation index: prothrombin time(PT), interntionl normlized ratio(INR), fibrin(Fib), activated partial thromboplastin time (APTT), thrombin time(TT), continuous non - invasive hemodynamic monitor (CNAP) was used for continuous measurement: cardiac output (CO), heart rate (HR), stroke volume (SV), pulse pressure variation rate (PPV), systemic vascular resistance index (SVRI), mean arterial pressure (MAP); pulse oxygen monitoring instrument is used for monitoring SPO₂ (pulse oxygen); the total vascular density (TVD), perfusion vascular density (PVD), proportion of perfused vascular(PPV), and microvascular flow index (MFI) of sublingual microcirculation were observed by using peripheral dark field imaging (SDF) monitoring technique. Results: Compared with the Shanghai group, the RBC and HGB levels in the Huzhu group and the Guoluo group were significantly increased (P＜0.05), while PLT levels were significantly decreased (P＜0.05); The levels of PT, Fib, APTT, TT, CO, HR, SV, MAP and SPO₂ in the Huzhu group were significantly decreased (P＜0.05), while the levels of TVD, PVD, PPV and MFI were significantly increased (P＜0.05). In Guoluo group, the levels of HCT, Fib, CO, SV, PPV, MAP, TVD and PVD were significantly increased (P＜0.05), while the levels of PT, INR, TT and SPO₂ were significantly decreased (P＜0.05). Compared with the Huzhu group, the levels of RBC, HGB, HCT, Fib and APTT of Guoluo group were significantly increased (P＜0.05); while the levels of SPO₂, TVD, PVD, INR and TT were significantly decreased (P＜0.05). Conclusion: The microcirculation of healthy people in different altitude areas is significantly different, and the microcirculation density of healthy people in high altitude areas is significantly higher than that in plain areas, especially in moderate altitude areas. Its special physiological significance is of guiding significance for the treatment of infectious shock and chronic altitude disease in plateau areas.