Effect of progressive early bed exercise on blood flow in lower limb of patients on mechanical ventilation in intensive care unit / 中华危重病急救医学

ABSTRACT

Objective To investigate the effect of progressive early bed physical activity on blood flow in lower limb of patients on mechanical ventilation in intensive care unit (ICU). Methods Adult patients with mechanical ventilation ≥ 72 hours admitted to ICU of the Affiliated Hospital of Zunyi Medical University from February 22nd to November 30th, 2016 were enrolled. The patients were randomly divided into experimental group and control group by random number table method. Patients in the two groups were given the same basic treatment, including antibiotics, analgesia and sedation, mechanical ventilation, nutritional support, and routine ICU activities such as maintaining functional position of limbs and raising of bed head. On the basis of those, the experimental group was given early bed physical activity with gradual enhancement of grades Ⅰ-Ⅲ according to the nerve, circulation and respiration situations, such as passive/active exercise of the bicycle, straight leg lifting exercise, etc. The exercise intensity was evaluated with target heart rate, and the exercise was performed for 15-30 minutes at a time, twice a day. The control group was given intermittent pneumatic compression (IPC), 30 minutes in each time, twice a day. Mean blood flow and blood volume were measured before and immediately, 5, 10 and 15 minutes after intervention on the 3rd day. Heart rate and blood pressure were measured at 5 minutes before intervention, during 5 minutes, and 5, 10, 15, 30 minutes after intervention on the 3rd day. Results 214 adult patients were selected, after excluding the patients who died during the intervention or gave up treatment, 160 patients were included in the data analysis, with 81 in the experimental group and 79 in the control group. The mean blood flow velocity and blood volume were increased in both groups, and the mean blood flow velocity and blood flow volume in the experimental group were significantly increased and lasted longer than those in the control group [mean blood flow velocity (mm/s) of the experimental group were 11.92±1.06, 18.19±0.17, 17.24±0.14, 15.48±0.12, 12.68±0.16, and that of the control group were 12.01±1.41, 15.65±0.18, 12.91±0.14, 12.13±0.12, 11.59±0.16, respectively, the time effect was F = 1 043.101, P = 0.000, the intervention effect was F = 151.001, P = 0.000, and the interaction effect between intervention and time was F = 224.830, P = 0.001; the blood volume (mL/min) of the experimental group were 3.39±0.96, 5.59±0.11, 5.16±0.12, 4.19±0.10. 3.35±0.09, and that of the control group were 3.28±0.82, 4.04±0.11, 3.40±0.12, 3.02±0.10, 3.00±0.10, respectively, the time effect was F = 680.405, P = 0.000, the intervention effect was F = 125.359, P = 0.000, and the interaction effect between intervention and time was F = 79.631, P = 0.012]. The heart rate and blood pressure of the two groups of patients in the course of intervention were increased first, then decreased and then slowly recovered to the change trend before intervention, but the index of the experimental group fluctuated greatly [heart rate (bpm) of the experimental group were 97.64±1.50, 113.91±1.36, 105.96±1.34, 98.52±1.48, 97.84±1.46, 97.54±1.48, and that of the control group were 97.03±1.57, 105.39±1.38, 96.76±1.35, 96.54±1.50, 97.22±1.48, 96.53±1.49, respectively, the time effect was F = 235.030, P = 0.000, the intervention effect was F = 39.473, P = 0.000, and the interaction effect between intervention and time was F = 3.494, P = 0.063; the systolic blood pressure (mmHg, 1 mmHg = 0.133 kPa) of the experimental group were 118.57±1.06, 133.05±1.01, 120.44±1.10, 117.78±1.07, 117.65±1.01, 118.14±1.00, and that of the control group were 118.10±1.08, 126.68±1.02, 118.23±1.11, 117.48±1.08, 118.04±1.03, 118.90±1.10, respectively, the time effect was F = 336.604, P = 0.000, the intervention effect was F = 26.350, P = 0.000, and the interaction effect between intervention and time was F = 0.948, P = 0.332; the diastolic blood pressure (mmHg) of the experimental group were 68.07±0.72, 72.79±0.73, 70.68±0.74, 69.30±0.72, 68.73±0.74, 67.80±0.73, and that of the control group were 68.51±0.73, 72.03±0.74, 70.05±0.75, 69.10±0.73, 68.41±0.75, 67.85±0.74, respectively, the time effect was F = 286.390, P = 0.000, the intervention effect was F = 4.812, P = 0.000, and the interactive effect between intervention and time was F = 0.055, P = 0.815]. Conclusions The effects of progressive early bed physical activity on the mean blood flow velocity and blood volume of lower limbs in ICU patients with mechanical ventilation are better than those of IPC. Although the fluctuation of heart rate and blood pressure is large, it does not cause any harm to the patients.