see also: [[ARDS]], [[Ventilator strategies]]
> [!key points]
> - TV 8mL/kg PBW → 6mL/kg
> - O2 88-95%
> - start PEEP 10 titrate to table
> - RR current minute ventilation of patient (max 35/min)
# INCLUSION CRITERIA
Acute onset of
1. PaO2/FiO2 ≤ 300
2. Bilateral (patchy, diffuse, or homogeneous) infiltrates consistent with pulmonary edema
3. No clinical evidence of left atrial hypertension
# PART I: VENTILATOR SETUP AND ADJUSTMENT
1. Calculate **predicted body weight** (PBW) Males = 50 + 2.3 \[height (inches) - 60] . Females = 45.5 + 2.3 \[height (inches) -60]
2. Select any ventilator mode
3. Set ventilator settings to achieve initial ==VT = 8 ml/kg PBW==
4. Reduce VT by 1 ml/kg at intervals ≤ 2 hours until ==VT = 6ml/kg PBW==.
5. ==Set initial rate to approximate baseline minute ventilation== (not > 35 bpm).
6. Adjust VT and RR to achieve pH and plateau pressure goals below
> **oxygenation goal:** SpO2 88-95% (PaO2 55-80)
> **Plateau pressure goal:** ≤ 30 cm H2O
> **pH Goal:** 7.3 - 7.45
> I:E ratio goal: inspiration ≤ expiration duration
## Oxygenation 88-95% PEEP tables
Consider use of incremental FiO2/PEEP combinations such as shown below (not required) to achieve goal SpO2 88-95%
![[Pasted image 20240104121706.png]]
## PLATEAU PRESSURE GOAL: ≤ 30 cm H2O
Check Pplat (0.5 second inspiratory pause), at least q 4h and after each change in PEEP or VT.
- If Pplat > 30 cm H2O: decrease VT by 1ml/kg steps (minimum = 4 ml/kg).
- If Pplat < 25 cm H2O and VT< 6 ml/kg, increase VT by 1 ml/kg until Pplat > 25 cm H2O or VT = 6 ml/kg.
- If Pplat < 30 and breath stacking or dys-synchrony occurs: may increase VT in 1ml/kg increments to 7 or 8 ml/kg if Pplat remains < 30 cm H2O.
## pH GOAL: 7.30-7.45
Acidosis Management: (pH < 7.30)
- If pH 7.15-7.30: ==Increase RR until pH > 7.30== or PaCO2 < 25 (Maximum set RR = 35). .
- If **pH < 7.15**: ==Increase RR to 35==. If pH remains < 7.15, VT may be increased in 1 ml/kg steps until pH > 7.15 (Pplat target of 30 may be exceeded). May give NaHCO3
Alkalosis Management: (pH > 7.45) Decrease vent rate if possible.
# PART II: WEANING
A. Conduct a SPONTANEOUS BREATHING TRIAL daily when: 1. FiO2 ≤ 0.40 and PEEP ≤ 8 OR FiO2 < 0.50 and PEEP < 5. 2. PEEP and FiO2 ≤ values of previous day. 3. Patient has acceptable spontaneous breathing efforts. (May decrease vent rate by 50% for 5 minutes to detect effort.) 4. Systolic BP ≥ 90 mmHg without vasopressor support. 5. No neuromuscular blocking agents or blockade.