학술논문

Impact of BMI on outcomes in respiratory ECMO: an ELSO registry study
Document Type
Original Paper
Source
Intensive Care Medicine. 49(1):37-49
Subject
Extracorporeal membrane oxygenation
Obesity
Body mass index
Respiratory failure
Language
English
ISSN
0342-4642
1432-1238
Abstract
Purpose: The impact of body mass index (BMI) on outcomes in respiratory failure necessitating extracorporeal membrane oxygenation (ECMO) has been poorly described. We aimed to assess: (i) whether adults with class II obesity or more (BMI ≥ 35 kg/m2) have worse outcomes than lean counterparts, (ii) the form of the relationship between BMI and outcomes, (iii) whether a cutoff marking futility can be identified.Methods: A retrospective analysis of the Extracorporeal Life Support Organization (ELSO) Registry from 1/1/2010 to 31/12/2020 was conducted. Impact of BMI ≥ 35 kg/m2 was assessed with propensity-score (PS) matching, inverse propensity-score weighted (IPSW) and multivariable models (MV), adjusting for a priori identified confounders. Primary outcome was in-hospital mortality. The form of the relationship between BMI and outcomes was studied with generalized additive models. Outcomes across World Health Organisation (WHO)-defined BMI categories were compared.Results: Among 18,529 patients, BMI ≥ 35 kg/m2 was consistently associated with reduced in-hospital mortality [PS-matched: OR: 0.878(95%CI 0.798–0.966), p = 0.008; IPSW: OR: 0.899(95%CI 0.827–0.979), p = 0.014; MV: OR: 0.900(95%CI 0.834–0.971), p = 0.007] and shorter hospital length of stays. In patients with BMI ≥ 35 kg/m2, cardiovascular (17.3% versus 15.3%), renal (37% versus 30%) and device-related complications (25.7% versus 20.6%) increased, whereas pulmonary complications decreased (7.6% versus 9.3%). These findings were independent of confounders throughout PS-matched, IPSW and MV models. The relationship between BMI and outcomes was non-linear and no cutoff for futility was identified.Conclusion: Patients with obesity class II or more treated with ECMO for respiratory failure have lower mortality risk and shorter stays, despite increased cardiovascular, device-related, and renal complications. No upper limit of BMI indicating futility of ECMO treatment could be identified. BMI as single parameter should not be a contra-indication for respiratory ECMO.