Draft

10  Proning For ARDS

10.1 What this covers

  • PROSEVA
  • Protocol
  • Other analyses

10.2 Learning objectives

  • PROSEVA
  • Protocol
  • Other analyses

10.3 Bottom line / summary

  • Proned for at least 16 hours per day if:
  • Continued until there was:
  • https://pubmed.ncbi.nlm.nih.gov/14668608/
  • Retrospective analysis of intervention arm (n225)
  • PaO2 responders (20% improvement) had similar outcomes to nonresponders PaCO2 responders - drop in PaCO2 of 1 or more (mediated by a reduction in deadspace ventilation) had an improved survival - 35.1% vs 52.2%

10.4 Approach

  1. P:F 150 or less with PEEP 10 or more and FiO2 60% or more after 12-24h period of stability
  2. Head direction swapped every 2 hours
  3. Goal: Vt 6ml/kg, 7.2 - 7.45 pH, plat <30
  4. 87% received neuromuscular blockade.
  5. improvement above threshold for study inclusion

10.5 Red flags / when to escalate

  • TODO: List red flags that require urgent escalation.

10.6 Common pitfalls

  • TODO: Capture common errors or missed steps.

10.7 References

  • https://pubmed.ncbi.nlm.nih.gov/14668608/
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6363976/

10.8 Source notes

10.8.1 Proning For ARDS

11 Proning for ARDS

11.1 PROSEVA

11.1.1 Protocol

Proned for at least 16 hours per day if:

  • P:F 150 or less with PEEP 10 or more and FiO2 60% or more after 12-24h period of stability
  • Head direction swapped every 2 hours
  • Goal: Vt 6ml/kg, 7.2 - 7.45 pH, plat <30
  • 87% received neuromuscular blockade.

Continued until there was:

  • improvement above threshold for study inclusion
  • deterioration in P:F of 20% or more relative to supine on 2 consecutive days
  • mechanical or hemodynamic complication preventing proning
  • 28 days.

11.2 Other analyses

https://pubmed.ncbi.nlm.nih.gov/14668608/

Retrospective analysis of intervention arm (n=225)

PaO2 responders (20% improvement) had similar outcomes to nonresponders PaCO2 responders - drop in PaCO2 of 1 or more (mediated by a reduction in deadspace ventilation) had an improved survival - 35.1% vs 52.2%

This fits with Vd/Vt (deadspace fraction) being predictive of an increased risk of mortality in ARDS, even after adjusting for P:F ratio and PEEP (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6363976/)

Changes in driving pressure seem like they ought to be even more predictive?

11.3 Source materials