ARDS

ARDSnet Protocol
Inclusion

PaO₂/FiO₂ ≤300

Bilateral infiltrates

No clear LA HTN / cardiogenic edema

Oxygenation Goal

PaO₂ 55–80 mmHg

SpO₂ 88–95%

Minimum PEEP 5 cm H₂O

Vent Setup

Start Vt 8 mL/kg PBW

Reduce to 6 mL/kg PBW

Set RR near baseline minute ventilation, max 35

Plateau Goal

Pplat ≤30 cm H₂O

If >30, decrease Vt by 1 mL/kg steps to min 4

If <25 and Vt <6, increase by 1 mL/kg

Lower PEEP / Higher FiO₂
FiO₂ 0.3 0.4 0.4 0.5 0.5 0.6 0.7 0.7 0.7 0.8 0.9 0.9 0.9 1.0
PEEP 5 5 8 8 10 10 10 12 14 14 14 16 18 18–24
Higher PEEP / Lower FiO₂
FiO₂ 0.3 0.3 0.3 0.3 0.3 0.4 0.4 0.5 0.5 0.5–0.8 0.8 0.9 1.0 1.0
PEEP 5 8 10 12 14 14 16 16 18 20 22 22 22 24

Goal Tidal Volume

P/F Ratio

Definitions

  • P/F <300: mild 200–300, moderate 100–200, severe <100
  • PEEP >5
  • Onset <7 days
  • No elevated LVEDP (non-cardiogenic pulmonary edema)
  • Bilateral opacities

Causes

  • PNA
  • Sepsis
  • Pancreatitis
  • Aspiration

Treatment

  • Low TV (6cc/kg): reduces volutrauma
  • Plateau <30: reduces barotrauma
  • High PEEP: recruits alveoli and improved oxygenation
  • Proning: improves V/Q mismatching, mortality benefit if P/F <150
  • Paralytics: atracurium, short course if severer dyssynchrony or refractory hypoxemia
  • VV ECMO: used for refractory hypoxemia despite optimal vent settings (P/F <80-100)

Trials

  • ACURASYS → early paralysis improved oxygenation, unclear mortality benefit
  • PROSEVA → proning ≥16h/day ↓ mortality in severe ARDS (P/F <150)

PROSEVA Trial

28-day mortality in severe ARDS

Prone: 16.0% vs Supine: 32.8%

References

  1. Acute Respiratory Distress Syndrome Network. (2000). Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. The New England Journal of Medicine, 342(18), 1301–1308. https://doi.org/10.1056/NEJM200005043421801
  2. Acute Respiratory Distress Syndrome Network. (2004). Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome. The New England Journal of Medicine, 351(4), 327–336. https://doi.org/10.1056/NEJMoa032193
  3. ARDS Definition Task Force. (2012). Acute respiratory distress syndrome: The Berlin Definition. JAMA, 307(23), 2526–2533. https://doi.org/10.1001/jama.2012.5669
  4. Guérin, C., Reignier, J., Richard, J. C., Beuret, P., Gacouin, A., Boulain, T., Mercier, E., Badet, M., Mercat, A., Baudin, O., Clavel, M., Chatellier, D., Jaber, S., Rosselli, S., Mancebo, J., Sirodot, M., Hilbert, G., Bengler, C., Richecoeur, J., ... Ayzac, L. (2013). Prone positioning in severe acute respiratory distress syndrome. The New England Journal of Medicine, 368(23), 2159–2168. https://doi.org/10.1056/NEJMoa1214103
  5. Papazian, L., Forel, J. M., Gacouin, A., Penot-Ragon, C., Perrin, G., Loundou, A., Jaber, S., Arnal, J. M., Perez, D., Seghboyan, J. M., Constantin, J. M., Courant, P., Lefrant, J. Y., Guérin, C., Prat, G., Morange, S., & Roch, A. (2010). Neuromuscular blockers in early acute respiratory distress syndrome. The New England Journal of Medicine, 363(12), 1107–1116. https://doi.org/10.1056/NEJMoa1005372
  6. National Heart, Lung, and Blood Institute PETAL Clinical Trials Network. (2019). Early neuromuscular blockade in the acute respiratory distress syndrome. The New England Journal of Medicine, 380(21), 1997–2008. https://doi.org/10.1056/NEJMoa1901686
  7. Combes, A., Hajage, D., Capellier, G., Demoule, A., Lavoué, S., Guervilly, C., Da Silva, D., Zafrani, L., Tirot, P., Veber, B., Maury, E., Levy, B., Cohen, Y., Richard, C., Kalfon, P., Bouadma, L., Mehdaoui, H., Beduneau, G., Lebreton, G., ... Mercat, A. (2018). Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome. The New England Journal of Medicine, 378(21), 1965–1975. https://doi.org/10.1056/NEJMoa1800385
  8. Fan, E., Del Sorbo, L., Goligher, E. C., Hodgson, C. L., Munshi, L., Walkey, A. J., Adhikari, N. K. J., Amato, M. B. P., Branson, R., Brower, R. G., Ferguson, N. D., Gajic, O., Gattinoni, L., Hess, D., Mancebo, J., Meade, M. O., McAuley, D. F., Pesenti, A., Ranieri, V. M., ... Brozek, J. L. (2017). An official American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine clinical practice guideline: Mechanical ventilation in adult patients with acute respiratory distress syndrome. American Journal of Respiratory and Critical Care Medicine, 195(9), 1253–1263. https://doi.org/10.1164/rccm.201703-0548ST
  9. Qadir, N., Sahetya, S. K., Munshi, L., Summers, C., Abrams, D., Beitler, J. R., Bellani, G., Brower, R. G., Burry, L., Chen, J. T., Hodgson, C., Hough, C. L., Lamontagne, F., Law, A. C., Papazian, L., Pham, T., Rochwerg, B., Rubenfeld, G. D., Theerawit, P., ... Fan, E. (2024). An update on management of adult patients with acute respiratory distress syndrome: An official American Thoracic Society clinical practice guideline. American Journal of Respiratory and Critical Care Medicine, 209(1), 24–36. https://doi.org/10.1164/rccm.202311-2011ST