1. Multiple choice questions for the online journal club discussion of:
Efficacy and economic assessment of conventional ventilatory support
versus extracorporeal membrane oxygenation for severe adult respiratory
failure (CESAR): a multicentre randomised controlled trial, The Lancet, Volume
374, Issue 9698, 17 October 2009-23 October 2009, Pages 1351-1363
1) CESAR was a “pragmatic” trial meaning that:
A. It was conducted in a relaxed manner
B. The investigators were chosen regardless of their own practice
C. Bias was avoided by limiting the number of participants
D. The trial was designed to reflect the way that respiratory support was provided
E. The results were not generalizable outside the hospitals involved in the trial
2) In relation to follow up in the CESAR trial:
A. A single primary endpoint was used
B. Health status at 12 months was assessed
C. Lung function was not assessed at 6 months
D. Activities of daily living were not assessed
E. Severe disability at 6 months was assessed
3) Significant differences between the two groups in the trial did NOT include:
A. Prone ventilation
B. Age
C. Use of high frequency oscillatory ventilation
D. The use of steroids
E. The use of low volume, low pressure ventilation
4) In terms of the treatment effect found with referral for consideration of ECMO
A. Consideration of ECMO led to a gain of 0.5 QALY at 6 months
B. The absolute risk reduction in favor of consideration for ECMO was 32%
C. 47% of non-ECMO patients survived to 6 months without severe disability
D. The number needed to treat was 16 patients
E. If 3 patients in the treatment group has all survived without severe disability at 6
months, the primary outcome would not have been statistically significant
5) Some criticisms of the trial include:
A. The recruitment period was too short
B. The economic evaluation is not generalizable because it is in US dollars
C. A concern that current standard of care may not have been applied in the control
group
2. D. The mortality due to ARDS is not changing, and the trial does not reflect this
E. A single endpoint, which needs to be interpreted with caution
Answers:
1.D. The CESAR trial was said to be pragmatic, as it was designed to study not just the
therapy of ECMO, but the way that the referral for ECMO occurred within a complex
system.
2.E. A combined endpoint of death and severe disability at 6 months was used.
3.B. The groups were evenly matched in age, if not several other important parameters.
4.C. 47% of patients survived to 6 months without disability in the conventional group, and
63% in the ECMO consideration group (absolute RR 16%).
5.C. There is evidence that lung protective ventilation was not routinely practiced in the
conventional group.