关键词:

急性呼吸窘迫综合征, 重度, 电阻抗断层扫描, 呼气末正压, ARDSnet

Abstract:

Objective　To investigate the impact of electrical impedance tomography (EIT) and the ARDSnet titration method for positive end-expiratory pressure (PEEP) on the short-term prognosis of moderate to severe acute respiratory distress syndrome (ARDS). Method　This study was a prospective investigation. A total of 100 patients with severe ARDS admitted to Xuzhou First People's Hospital from January 2022 to December 2023 were selected as study subjects. Patients were randomly assigned to the EIT group and the ARDSnet group using a computer-generated random number table, with 50 cases in each group. The EIT group included 30 males and 20 females, with an average age of (55.62±8.45) years and a body mass index (BMI) of (26.51±3.64) kg/m². The ARDSnet group included 28 males and 22 females, with an average age of (55.93±8.61) years and a BMI of (27.06±3.73) kg/m². Both groups received continuous invasive mechanical ventilation. The ARDSnet group set the PEEP value according to the oxygenation methods recommended by ARDSnet, aiming to maintain oxygen saturation (SpO₂) between 88%-95% and arterial oxygen partial pressure (PaO₂) between 55-80 mmHg. The EIT group underwent EIT measurements during the supine PEEP titration process, with EIT data recorded. Starting from an initial pressure of 5 cmH₂O, PEEP was gradually increased using an incremental method, raising it by 2 cmH₂O every 2 minutes until a plateau pressure of 30 cmH₂O was reached, ensuring it did not exceed this upper limit. Compare the levels of hemodynamics, pulmonary edema, arterial blood gas analysis, respiratory mechanics parameters, and treatment efficacy between two groups treated for 12 hours and on days 1, 2, 3, and 5. Statistical analysis was performed using χ² tests and t tests. Result　On day 5, the heart rate in the EIT group was lower, while the mean arterial pressure on days 3 and 5, and cardiac index, arterial oxygen partial pressure, oxygenation index, tidal volume, and compliance on days 2, 3, and 5 were higher than those in the ARDSnet group. At all-time points, extravascular lung water and the permeability index, flow rate, peak airway pressure, plateau airway pressure, transpulmonary pressure, and driving pressure on days 2, 3, and 5 were lower in the EIT group compared to the ARDSnet group, with statistically significant differences for all intergroup comparisons, time points, and interactions (all P<0.05). The 28-day mortality rate in the EIT group was 20.0% (10/50), while in the ARDSnet group it was 38.0% (19/50), with a statistically significant difference (χ²=3.934, P=0.047). The duration of invasive mechanical ventilation and the length of stay in the intensive care unit (ICU) were both shorter in the EIT group compared to the ARDSnet group [(14.25±5.63) d vs. (16.83±6.41) d, (21.52±8.76) d vs. (25.39±9.26) d], with statistically significant differences (all P<0.05). Conclusion　Severe ARDS patients are treated with EIT therapy, which effectively reduces mortality, shortens mechanical ventilation time, and ICU stay by improving lung compliance, reducing airway resistance, optimizing ventilation strategies, and implementing fine fluid management.

Key words: Acute respiratory distress syndrome, Severe, Electrical impedance tomography,  , Positive end-expiratory pressure,  , ADRSnet