Objective: To investigate the effect of early pulmonary rehabilitation (PR) training on the improvement of respiratory function in patients with acute respiratory distress syndrome (ARDS) after weaning of invasive mechanical ventilation in the intensive care unit (ICU).
Methods: The retrospective cohort research method was used. The clinical information of adult patients with ARDS receiving invasive mechanical ventilation admitted to the ICU of Qingdao Municipal Hospital from January 2019 to March 2023 was collected. The patients were divided into a control group and an observation group according to off-line training program. The control group received traditional training after weaning, and the observation group received the early PR training after weaning. Other treatments and nursing were implemented according to the routine of the ICU. The scores of the short physical performance battery (SPPB) on day 3-day 6 of the weaning training, respiratory muscle strength, level of interleukin-6 (IL-6), number of aspirations of sputum after weaning, length of stay after weaning, rehospitalization rate within 6 months after discharge, and pulmonary function indicators at discharge and 3 months after discharge [peak expiratory flow (PEF), forced expiratory volume in one second/forced vital capacity ratio (FEV1/FVC), and vital capacity (VC)] of the two groups of patients were compared. The Kaplan-Meier survival curve was drawn to analyze the cumulative survival rate of patients 6 months after discharge.
Results: A total of 50 of which 25 cases received the traditional training after weaning, 25 cases received the early PR training after weaning. There was no significant difference in gender, age, acute physiology and chronic health evaluation II (APACHE II), oxygenation index upon admission, etiological diagnosis of ARDS upon admission, time of invasive ventilation, mode of invasive mechanical ventilation, pulmonary function indicators at discharge, and other baseline data of the two groups. The SPPB questionnaire scores and respiratory muscle strength in both groups were increased gradually with the extended offline training time, the serum level of IL-6 in both groups were descend gradually with the extended offline training time, especially in the observation group [SPPB questionnaire score in the observation group were 7.81±0.33, 8.72±0.53, 9.44±0.31, 10.57±0.50, while in the control group were 7.74±0.68, 8.73±0.37, 8.72±0.40, 9.33±0.26, effect of time: F = 192.532, P = 0.000, effect of intervention: F = 88.561, P = 0.000, interaction effect between intervention and time: F = 24.724, P = 0.000; respiratory muscle strength (mmHg, 1 mmHg≈0.133 kPa) in the observation group were 123.20±24.84, 137.00±26.47, 149.00±24.70, 155.40±29.37, while in the control group were 129.00±20.34, 126.00±24.01, 132.20±25.15, 138.60±36.67, effect of time: F = 5.926, P = 0.001, effect of intervention: F = 5.248, P = 0.031, interaction effect between intervention and time: F = 3.033, P = 0.043; serum level of IL-6 in the observation group were 80.05±6.81, 74.76±9.33, 63.66±10.19, 56.95±4.72, while in the control group were 80.18±7.21, 77.23±9.78, 71.79±10.40, 66.51±6.49, effect of time: F = 53.485, P = 0.000, effect of intervention: F = 22.942, P = 0.000, interaction effect between intervention and time: F = 3.266, P = 0.026]. Compared with the control group, the number of aspirations of sputum after weaning of patients in the observation group significantly decreased (number: 22.46±1.76 vs. 27.31±0.90), the length of ICU stay after weaning significantly became shorter (days: 6.93±0.95 vs. 8.52±2.21), and the rehospitalization rate within 6 months after discharge significantly decreased [20.00% (5/25) vs. 48.00% (12/25)]. There were significant differences. The pulmonary function indicators 3 months after discharge of two groups of patients significantly increased compared with those at discharge and those of the observation group were significantly higher than those of the control group [PEF (L/min): 430.20±95.18 vs. 370.00±108.44, FEV1/FVC ratio: 0.88±0.04 vs. 0.82±0.05, VC (L): 3.22±0.72 vs. 2.74±0.37, all P < 0.05]. The Kaplan-Meier survival curve showed that the cumulative survival rate of patients 6 months after discharge of patients in the observation group was significantly higher than that of patients in the control group [76.9% vs. 45.5%, hazard ratio (HR) = 0.344, P = 0.017].
Conclusions: Early PR training can significantly improve the respiratory function of patients with ARDS after weaning of invasive mechanical ventilation. Continuous active respiratory training after discharge can improve the respiratory function of patients and effectively decrease mortality.