RT Journal Article
SR Electronic
T1 Time Course of Decreased Lung Compliance in Subjects Requiring Permanent Ventilation Dependence
JF Respiratory Care
FD American Association for Respiratory Care
SP 3599088
VO 66
IS Suppl 10
A1 Onozawa, Shinichi
A1 Someya, Fujiko
A1 Eiji, Nuriya
YR 2021
UL http://rc.rcjournal.com/content/66/Suppl_10/3599088.abstract
AB Background: Lung compliance in patients with ventilator management affects the ventilatory status and mortality. However, there are few studies on permanent ventilation dependence (PVD) and time course studies on lung compliance have not been conducted. We aimed to clarify the longitudinal factors affecting lung compliance if there exist the time course deterioration during chronic period in PVD subjects. Methods: A prospective cohort study was performed on 24 PVD subjects on ventilator for about 6 years evaluated twice between 2019 and 2020. We compared static (Cst) and dynamic (Cdyn) lung compliance and alveolar-arterial PO2 difference (P (A-a)O2) between the two measurements, and examined correlations in Cst and Cdyn over time with BMI, age, ventilator management days, and the incidence of pneumonia. Subjects were divided into two groups according to the presence of atelectasis, and Cst, Cdyn, and P (A-a)O2 were compared between the two groups. Results: The primary diseases of the subjects were central nervous system disorders, such as spinal cord injury, hypoxic encephalopathy, head trauma, subarachnoid hemorrhage, and brainstem infarction, and neuromuscular diseases such as ALS and Parkinson's disease. The comparison of Cst and Cdyn between baseline and follow-up revealed no significant difference. Atelectasis was observed in 13 subjects at baseline, 4 of whom discontinued the study, and the remaining 9 subjects had atelectasis at follow-up without new atelectasis. One subject who had no atelectasis was excluded from the present study because of death. There was no difference in Cst and Cdyn between the groups in terms of atelectasis. In contrast, the values of both Cst and Cdyn slightly decreased in the group without atelectasis and increased in the group with atelectasis over the course of 1 year, and significant differences were noted between the two groups in the values (Table 1). No significant differences were found in the difference in P (A-a)O2 between groups in terms of atelectasis. A decrease in Cst was related to an increased BMI (r = -0.41, P = 0.047), but P (A-a)O2, age, ventilatory management days, and pneumonia incidence were not associated with the differences in Cst or Cdyn (Table 2). Conclusions: Increased BMI affected lung compliance in PVD subjects during one year of chronic period. Regarding atelectasis, its relationship with differences in Cst and Cdyn was not clear and impaired lung compliance was thought to be almost settled in several years of PVD. Table 1. Cst, Cdyn, and A-aDO2 t-test by the presence of atelectasisTable 2. Correlation coefficients for each item with differences in Cst and Cdyn