ARDSnet Protocol Settings: The Card, in Actual HTML
Published
ARDSnet protocol settings are the NHLBI ARDS Network’s ventilator rules for adults with acute lung injury or ARDS: tidal volume started at 8 mL/kg predicted body weight and stepped down to 6, plateau at or below 30 cm H2O, SpO2 88-95% or PaO2 55-80 mmHg with optional paired PEEP/FiO2 steps, and a pH goal of 7.30-7.45. These are reference values to verify against the patient, your local protocol, and your scope of practice.
| Setting | What the card says | Source |
|---|---|---|
| Predicted body weight | Male: 50 + 2.3 x (height in inches - 60). Female: 45.5 + 2.3 x (height in inches - 60) | Card (University of Michigan copy) |
| Mode | Select any ventilator mode | Card (University of Michigan copy); PMC4139286 |
| Initial tidal volume | 8 mL/kg PBW | Card (University of Michigan copy); PMC4139286 |
| Step-down | Reduce by 1 mL/kg at intervals of two hours or less until 6 mL/kg | PMC4139286; card |
| Rate | Approximate baseline minute ventilation, not above 35 breaths/min | Card (University of Michigan copy); PMC4139286 |
| Oxygenation goal | PaO2 55-80 mmHg or SpO2 88-95% | Card (University of Michigan copy); NBK441904 |
| Minimum PEEP | 5 cm H2O | Card (University of Michigan copy) |
| PEEP/FiO2 | Paired steps from one of two tables (not required) | Card (University of Michigan copy) |
| Plateau goal | 30 cm H2O or less, checked with a 0.5-second end-inspiratory pause | Goal: card, PMC4139286. Pause: ARMA (NEJM 2000) |
| pH goal | 7.30-7.45 | Card (University of Michigan copy) |
| I:E goal | Inspiration no longer than expiration | Card (University of Michigan copy) |
ARDSNet Part I, the settings half of the card. ICU protocol values for adults with ALI/ARDS.
The card is dated July 2008. The ARDS Network closed in 2014, and its site still lists this as its only ventilator protocol card (ardsnet.org). This page transcribes Part I; Part II, weaning, stays off this page.
Verify who the ARDSNet protocol card is written for
The ARDSNet protocol card applies to adults with acute onset of: PaO2/FiO2 at or below 300, corrected for altitude; bilateral infiltrates consistent with pulmonary edema; and no clinical evidence of left atrial hypertension (card, via the University of Michigan copy). ARMA, the trial behind its tidal volume and plateau rules, reported 31.0% versus 39.8% mortality in that ALI/ARDS population (NEJM 2000), never extended to every ventilated adult.
Calculate ARDSNet tidal volume: start at 8 mL/kg, step down to 6
The card says: select any ventilator mode (card, via the University of Michigan copy; PMC4139286). The card sets initial tidal volume at 8 mL/kg PBW, then reduces it by 1 mL/kg at intervals of two hours or less until 6 mL/kg (PMC4139286; card). The 8-to-6 step is routine and time-driven. Only the steps below 6, toward a 4 mL/kg floor, are plateau-driven, covered next.
Predicted body weight and Devine IBW give the same number
The card’s PBW formulas are arithmetically identical to the Devine formula this site uses for ideal body weight, so PBW and IBW give the same number here. See the tidal volume chart by height rather than rebuilding it. The formula is only formally defined from about 5 feet up, so the worked example below stays above that line.
Set the rate to baseline minute ventilation, 35 at most
Initial rate approximates baseline minute ventilation, not above 35 breaths/min, then rate and tidal volume adjust to reach the pH and plateau goals below (card). The rate math itself sits under working the minute ventilation formula at the bedside.
| Step | mL/kg PBW | Tidal volume (mL, truncated) | What drives the step |
|---|---|---|---|
| Start | 8 | 474 | Initial setting |
| Step 1 | 7 | 415 | Time (interval of 2 hours or less) |
| Step 2 | 6 | 355 | Time (interval of 2 hours or less) |
| Plateau step | 5 | 296 | Plateau over 30 cm H2O |
| Plateau step | 4 | 237 | Plateau over 30 cm H2O, card minimum |
One patient through the card’s step-down. Truncated, not rounded, the way the app and the site’s chart do it.
5′6″ (66 in) adult female. PBW = 45.5 + 2.3 x 6 = 59.3 kg.
Read the ARDSNet PEEP/FiO2 table, both versions, cell for cell
Oxygenation goal: PaO2 55-80 mmHg or SpO2 88-95%, for this ALI/ARDS population only, never a general oxygen target (card; NBK441904). Minimum PEEP is 5 cm H2O. The card’s words: consider use of incremental FiO2/PEEP combinations such as shown below (not required) to achieve goal. The card prints both tables and states no preference between them.
Lower PEEP/higher FiO2 table
The card prints this table first.
| FiO2 | PEEP (cm H2O) |
|---|---|
| 0.3 | 5 |
| 0.4 | 5 |
| 0.4 | 8 |
| 0.5 | 8 |
| 0.5 | 10 |
| 0.6 | 10 |
| 0.7 | 10 |
| 0.7 | 12 |
| 0.7 | 14 |
| 0.8 | 14 |
| 0.9 | 14 |
| 0.9 | 16 |
| 0.9 | 18 |
| 1.0 | 18–24 |
Lower PEEP/higher FiO2, as printed on the ARDSNet card. Each row reproduces one pairing. The card presents these combinations as optional examples for reaching its oxygenation goal, not as a mandatory row-by-row sequence.
The 18–24 cell is the card’s own range, not four separate pairings. Cells: ARDSNet card (University of Michigan copy).
Higher PEEP/lower FiO2 table
At FiO2 0.5, the lower table pairs PEEP 8 or 10; the higher table pairs 16 or 18, and 20 through its 0.5-0.8 cell. Same FiO2, very different PEEP, so the table in use matters before anything changes.
| FiO2 | PEEP (cm H2O) |
|---|---|
| 0.3 | 5 |
| 0.3 | 8 |
| 0.3 | 10 |
| 0.3 | 12 |
| 0.3 | 14 |
| 0.4 | 14 |
| 0.4 | 16 |
| 0.5 | 16 |
| 0.5 | 18 |
| 0.5–0.8 | 20 |
| 0.8 | 22 |
| 0.9 | 22 |
| 1.0 | 22 |
| 1.0 | 24 |
Higher PEEP/lower FiO2, as printed on the ARDSNet card. This table generally pairs a given FiO2 with higher PEEP. The tables share 0.3/5, and at FiO2 1.0 the higher table’s PEEP values of 22 and 24 fall within the lower table’s 18–24 range.
The 0.5–0.8 cell is the card’s own range, paired with PEEP 20. Cells: ARDSNet card (University of Michigan copy); FiO2 0.4/PEEP 16 per Budinger and Mutlu (Chest 2013).
When to increase PEEP vs FiO2?
The card offers these paired PEEP/FiO2 combinations as optional examples for reaching the oxygenation goal. Adjacent printed pairs often change only one value. The tables do not establish a universal rule that every patient must move through each row or that intermediate settings are forbidden. The card calls for plateau pressure to be checked after each PEEP or tidal-volume change. The treating team’s protocol and the patient’s response govern adjustment.
Recheck plateau pressure against the 30 cm H2O goal
Plateau goal: at or below 30 cm H2O (card; PMC4139286), measured after a 0.5-second pause at the end of inspiration (ARMA, NEJM 2000;342:1301-1308, PubMed 10793162). Recheck plateau after each change in PEEP or tidal volume (card, University of Michigan copy). Reading it needs a vent that can hold an inspiratory pause and a passive patient; measuring it with an inspiratory hold is covered at how to measure plateau pressure with an inspiratory hold.
| If | The card says |
|---|---|
| Pplat over 30 cm H2O | Decrease tidal volume in 1 mL/kg steps, minimum 4 mL/kg |
| Pplat under 25 cm H2O and Vt under 6 mL/kg | Increase tidal volume in 1 mL/kg steps until Pplat over 25 cm H2O or Vt reaches 6 mL/kg |
| Pplat under 30 cm H2O with breath stacking or dyssynchrony | May increase tidal volume in 1 mL/kg steps to 7 or 8 mL/kg if Pplat stays at or below 30 cm H2O |
Plateau-driven tidal volume changes. These are the only steps below 6 mL/kg.
Interpret the ARDSNet pH goal and the acidosis steps
pH goal: 7.30-7.45 (card). Rate climbs first as pH drops. For acidosis, tidal volume may rise only once pH stays below 7.15 at a rate of 35, and the card allows the 30 cm H2O plateau target to be exceeded there, the one place it trades that goal away. The card also lists “may give NaHCO3” with no dose: an option, not a directive. Rate falls for alkalosis, pH above 7.45. Every rule here needs a blood gas.
| pH | The card says |
|---|---|
| 7.30–7.45 | Goal |
| 7.15–7.30 | Increase rate until pH above 7.30 or PaCO2 below 25 (maximum set rate 35) |
| Below 7.15 | Increase rate to 35 |
| Still below 7.15 | Tidal volume may increase in 1 mL/kg steps until pH above 7.15 (plateau target of 30 may be exceeded); may give NaHCO3 |
| Above 7.45 | Decrease rate if possible |
Acidosis and alkalosis steps. Every row needs a blood gas.
The I:E ratio goal
The card’s goal: inspiration no longer than expiration. See the I:E ratio on a ventilator for the numbers.
Compare the card with a transport ventilator and the app
What travels with the patient: the tidal volume target and step; the PEEP/FiO2 pair in force; the plateau goal if the device can hold a pause; and SpO2 against the 88-95% goal for this population. What doesn’t travel without a blood gas: PaO2, the pH goal, and the acidosis steps. The ARDSNet card allows any ventilator mode, so these ARDS ventilator settings are not tied to one mode; how each mode delivers them is covered at ventilator modes explained for transport crews. The app computes tidal volume from IBW at 4 to 8 mL/kg, truncated, with no PEEP/FiO2 ladder, no plateau input, and no pH logic. The clinician chooses the step and the pair, against local protocol and medical control.
Part II of the card, weaning and spontaneous breathing trials, is ICU liberation and stays off this page. Once settings are verified, the next step is managing the ventilated adult after intubation, and the hub’s lung-protective ventilation settings cover the non-ARDS starting point.
Residual questions
What is the recommended tidal volume in the ARDSNet protocol?
6 mL/kg PBW, reached by stepping down from an initial 8, with further plateau-driven steps to a 4 mL/kg floor and, in specific cases, back to 7 or 8 (card). ARMA’s lower-volume arm started at 6 mL/kg PBW (NEJM 2000 abstract); the 2008 card starts at 8 and reaches 6 within hours.
Do you want high or low PEEP with ARDS?
ALVEOLI found similar outcomes with lower or higher PEEP at 6 mL/kg tidal volume and a 30 cm H2O plateau limit (Brower et al., NEJM 2004;351:327-336), and the 2024 ATS guideline conditionally suggests higher PEEP without lung recruitment maneuvers in moderate to severe ARDS (Qadir et al., AJRCCM 2024;209(1):24-36), so the table stays the treating team’s call under local protocol.
Sources
- The Acute Respiratory Distress Syndrome Network (Brower RG, et al). Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. New England Journal of Medicine. 2000;342(18):1301-1308. https://pubmed.ncbi.nlm.nih.gov/10793162/
- NIH NHLBI ARDS Clinical Network. Mechanical Ventilation Protocol Summary (July 2008 card), as reproduced by Michigan Medicine, University of Michigan (last reviewed 2021). https://ecosystem.tactuum.com/university-of-michigan/respiratory/ardsnet-mechanical-ventilation-protocol/
- Wilson JG, Matthay MA. Mechanical ventilation in acute hypoxemic respiratory failure: a review of new strategies for the practicing hospitalist. Journal of Hospital Medicine. 2014;9(7):469-475. https://pmc.ncbi.nlm.nih.gov/articles/PMC4139286/
- Budinger GRS, Mutlu GM. Balancing the risks and benefits of oxygen therapy in critically ill adults. Chest. 2013;143(4):1151-1162. https://pmc.ncbi.nlm.nih.gov/articles/PMC3616683/
- Brower RG, et al; NHLBI ARDS Clinical Trials Network. Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome. New England Journal of Medicine. 2004;351(4):327-336. https://pubmed.ncbi.nlm.nih.gov/15269312/
- Qadir N, Sahetya S, Munshi L, et al. 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. 2024;209(1):24-36. https://doi.org/10.1164/rccm.202311-2011ST
- Levine A, Mora JI. Positive End-Expiratory Pressure (PEEP). In: StatPearls. StatPearls Publishing; updated 2025 Sep 14. https://www.ncbi.nlm.nih.gov/books/NBK441904/
- NIH NHLBI ARDS Network. About the NHLBI ARDS Network; Tools. ardsnet.org, site content dated 2014 (read 2026-09-24).
