View source for EBQ:ARDSnet Trial

{{JC info
| title=Ventilation With Lower Tidal Volumes As Compared With Traditional Tidal Volumes For Acute Lung Injury And The Acute Respiratory Distress Syndrome
| abbreviation=ARDSNet
| expansion=Acute Respiratory Distress Syndrome Network
| published=2000
| author= Brower RG, et al
| journal=The New England Journal of Medicine
| year=2000
| volume=342
| issue=18
| pages=1301-1308
| pmid=10793162
| fulltexturl=http://www.nejm.org/doi/full/10.1056/NEJM200005043421801
| pdfurl=http://www.nejm.org/doi/pdf/10.1056/NEJM200005043421801
| status=Complete
}}

==Clinical Question==
Does a lung protective strategy of low tidal volumes in patients with Acute Lung Injury (ALI) and Acute Respiratory Distress Syndrome (ARDS) decrease mortality and ventilator-free days when compared to traditional ventilation strategies. 

==Conclusion==
In patients with ALI/ARDS, lower tidal volumes of 6mL/kg predicted body weight reduces mortality and decreases length of time on mechanical ventilation.

==Major Points== 
*Acute Respiratory Distress Syndrome results from alveolar damage and barotrauma are associated with elevated plateau pressures and higher tidal volume ventilations
*The trial was stopped early when patients in the low tidal volumes arm showed a significant decrease in mortality and more ventilator-free days compared to the traditional tidal volumes arm.
==Guidelines==
See [[Sepsis]] for guideline recommendations

==Design==
*Multicenter, randomized trial of 861 patients in parallel-group in 10 university-affiliated ARDSNet centers
**Low tidal volumes: Starting at 6ml/kg PBW and plateau pressure ≤30cmH2O (n=432)
**Traditional tidal volumes: starting at 12ml/kg PBW and plateau pressure of ≤50cmH2O (n=429)
*Enrollment: March 1996 to March 1999 (terminated early after the fourth interim analysis)
*Follow-up: 180 days or until home breathing independently

==Population==
===Inclusion Criteria===
*Age ≥18 years
*Receiving mechanical ventilation
*Diagnosis of ALI/ARDS ≤36h prior to enrollment; defined as:
**Acute decrease in PaO2/FiO2ratio to ≤300
**CXR: Bilateral pulmonary infiltrates
**PCWP of ≤18mmHg without evidence of left atrial hypertension

===Exclusion Criteria===
*Pregnancy
*Increased ICP, neuromuscular disease imparing spontaneous breathing, sickle cell disease, or severe chronic respiratory disease
*Weight more than 1kg/cm of height
*Burns >30% of BSA
*Estimated 6-month mortality rate >50%
*History of bone marrow or lung transplantation
*Child-Pugh class C liver disease
*Participation in other trials w/in 30 days

===Baseline Characteristics===
*Mean age: 51.5 years
*Sex: Female (40.5%)
*Ethnicity:
**White: 73%
**Black: 17.5%
**Hispanic: 6%
*APACHE III score: 82.5
*Mean PaO2:FiO2: 136
*Mean tidal volume: 670 mL
*Mean minute ventilation: 13.4 vs. 12.7 L/min (P=0.01)

==Interventions==
Patients randomly assigned to receive mechanical ventilation (volume-assist-control mode) with following strategies for tidal volume:
* Low tidal volumes (lung protective strategy): Starting at 6ml/kg PBW to maintain plateau pressure ≤30cm H<sub>2</sub>O (n=432)
* Traditional tidal volumes: Starting at 12ml/kg to maintain plateau pressure of ≤50cm H<sub>2</sub>O (n=429)

Patients monitored until day 28 or death for signs of system failure:
*Circulatory failure: SBP ≤90mmHg or need for vasopressor
*Coagulation failure: Platelets ≤80,000 mm3
*Hepatic failure: Bilirubin ≥2mg/dL
*Renal failure: Creatinine ≥2mg/dL

==Outcomes==

===Primary Outcomes===
*180-day mortality
**31.0% vs. 39.8% (RR 0.78; P=0.007)
*Ventilator-free days (Days 1-28)
**12 vs. 10 (P=0.007)
*Breathing without assistance by day 28
**65.7% vs. 55.0% (P<0.001; NNT 9)

===Secondary Outcomes===
*Days w/o non-pulmonary organ or system failure (Days 1 to 28)
**15 vs. 12 (P=0.006)
*Days w/o circulatory failure
**19 vs. 17 (P=0.004)
*Days w/o coagulation failure
**21 vs. 19 (P=0.004)
*Days w/o renal failure
**20 vs. 18 (P=0.005)
*Barotrauma (New PTX, pneumomediastinum, subcutaneous emphysema, pneumatocele)
**10% vs. 11% (P=0.43)
*Mean tidal volumes (ml/kg PBW)
**6.2 vs. 11.8 (P<0.001)
*Mean plateau pressures (cm H2O)
**25 vs. 33 (P<0.001)
*Peak inspiratory pressures (cm H2O)
**32 vs. 39 (P<0.05)

==Criticisms==

==Funding==
The National Heart, Lung, and Blood Institute.
==See Also==
{{Mechanical ventilation pages}}

==References==
<references/>

[[Category:Pulmonary]][[Category:Critical Care]][[Category:EBQ]]