Registry setting and procedures:
The Swedish Intensive Care Registry (SIR) collects a comprehensive dataset of patient characteristics, intensive care procedures and outcomes using detailed guidelines.
Continuous data are collected as raw data, validated locally and transferred electronically to the registry for central validation (confirmed to be within prespecified limits and inconsistencies and illogical entries identified). If necessary, data are returned for correction and revalidation before being accepted and added to the master database.
Study participants:
Patients with COPD as the principal diagnosis during their ICU stay were included in the study cohort. When patients had multiple admissions during the study period due to COPD the last admission only was included. Patients were excluded when nursing workload scores indicated active ventilation support during the first 24 hours but information on type of support (non-invasive or invasive ventilation) was lacking. Participants with missing vital status were also excluded from analysis.
Patients were grouped according to the mode of the first-line ventilation support that was given during the initial 24 hours in ICU. The Standard therapy group did not receive any active ventilation support, the NIV only group received non-invasive ventilation support only, the NIV + Invasive mechanical ventilation (IMV) group received NIV followed by intubation and invasive ventilation support and, the IMV group were intubated and received invasive ventilation support without any preceding NIV trial.
