1. Volume 111, Issue 6, Pages 1631-1638 (June 1997)
Human and Financial Costs of Noninvasive Mechanical Ventilation in Patients Affected by COPD and Acute Respiratory Failure 
Stefano Nava, MD, Ilaria Evangelisti, RN, Ciro Rampulla, MD, Maria Laura Compagnoni, PhD, Claudio Fracchia, MD, Fiorenzo Rubini, MD 
CHEST 
Volume 111, Issue 6, Pages (June 1997)
DOI: /chest
Copyright © 1997 The American College of Chest Physicians Terms and Conditions

2. FIGURE 1
Ns, MDs, and RTs, workload in the first 48 h of MV. Data are mean±SD. Asterisk indicates p<0.05 compared with the first 6-h period.
CHEST  , DOI: ( /chest )
Copyright © 1997 The American College of Chest Physicians Terms and Conditions

3. FIGURE 2
Workload of the whole medical and paramedical personnel (total), Ns, MDs, and RTs, expressed as a percentage of the first 48 h of MV. Data are mean±SD. Asterisk indicates p<0.05 between NIMV and InMV.
CHEST  , DOI: ( /chest )
Copyright © 1997 The American College of Chest Physicians Terms and Conditions

4. FIGURE 3
N and MD workload (minutes per day) for the entire period of MV. Asterisk indicates p<0.05 between NIMV and InMV; two asterisks, p=0.01 between NIMV and InMV.
CHEST  , DOI: ( /chest )
Copyright © 1997 The American College of Chest Physicians Terms and Conditions