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Published on: May 26, 2023
Bilevel positive airway pressure in two moments after bariatric surgery
Eli Maria Pazzianotto-Forti1, Letícia Baltieri2, Patrícia Brigatto3
1. Programa de Pós-Graduação em Ciências do Movimento Humano, Universidade Metodista de Piracicaba, Unimep, Piracicaba, SP, Brasil.
Objective:
To investigate the use of Bilevel Positive Airway Pressure (BiPAP) in morbidly obese individuals in two moments following bariatric surgery (Roux-en-Y gastric bypass): post-anesthetic recovery (PAR) and first postoperative day (1PO).
Design:
Randomized and blinded clinical trial.
Methods:
We studied 40 morbidly obese individuals aged between 25 and 55 years who underwent pulmonary function test and chest X-ray preoperatively, and on the day of discharge (2nd day after surgery). They were randomly allocated into two groups: PAR-G (BiPAP in PAR for one hour), and 1PO-G (BIPAP for one hour on the 1PO).
Results:
In the PAR-G and 1PO-G, respectively there were significant reductions in slow vital capacity (SVC) (p=0.0007 vs. p<0.0001), inspiratory reserve volume (IRV) (p=0.0016 vs. p=0.0026), and forced vital capacity (FVC) (p=0.0013 vs. p<0.0001) and expiratory reserve volume (ERV) was maintained only for the PAR-G (p=0.4446 vs. p=0.0191). Comparing the groups, the SVC (p=0.0027) and FVC (p=0.0028) showed a significant difference between the treatments, while the PAR-G showed smaller declines in these capacities. The prevalence of atelectasis was 10% for the PAR-G and 30% for the 1PO-G (p=0.0027).
Conclusion:
Thus, the use of BiPAP in PAR can promote restoration of ERV and contribute to the reduction of atelectasis.
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