ARDS Management Protocol

February 2018

ARDS Criteria
Onset Within 1 week of a known clinical insult or new or worsening respiratory symptoms
Bilateral opacities—not fully explained by effusions, lobar/lung collapse, or nodules
Respiratory failure not fully explained by cardiac failure or fluid overload Need objective
assessment (eg, echocardiography) to exclude hydrostatic edema if no risk factor present
PaO2/FIO2 ≤ 300 mm Hg with PEEP or CPAP ≥ 5 cm H2O
Severity of Illness
Mid: 200 mm Hg < PaO2/FIO2 ≤ 300 mm Hg with PEEP or CPAP ≥ 5 cm H2O
Moderate: 100 mm Hg < PaO2/FIO2 ≤ 200 mm Hg with PEEP ≥ 5 cm H2O
Severe: PaO2/FIO2 ≤ 100 mm Hg with PEEP ≥ 5 cm H2O
Calculations
Calculate Ideal Body Weight (IBW):
Men = 50 + [(height (cm) -154) x 0.9]
Women = 45.5 + [(height (cm) -154) x 0.9]
Desired minute ventilation (MV)= IBW * 125

A Set Targets

Tidal volume 4-6 ml/kg of IBW

Plateau pressure: <30 cm H2O (preferably <28 cm H2O), may accept higher plateau If patient
has stiff chest wall or abdominal limitation (e.g., with massive ascites, large pleural effusion or
obese patients)
Driving pressure < 15 cm H2O
pH: 7.25-7.45
PaO2 55-80 mmHg or SpO2 88-95% and FiO2 ≤ 60%

1 Volume Control Mode

Pressure Regulation Mode (PRVC, CMV with autoflow, AC+, or APVcmv)
Set volume at 6 mL/kg of IBW
Decrease volume at 1 mL/kg to achieve the set plateau pressure goal
Set pressure alarm limit 37-50 cm H2O (dependent on the type of ventilator)
 Set rate at desired minute ventilation/VT: The respiratory rate will be set to avoid air trapping
whenever possible as determined by the inspection of the flow tracing and/or measurements
of intrinsic PEEP.
Adjust rate for the pH goal

1 Pressure Control Mode

Set pressure control less than 30
Adjust pressure to maintain VT 4-6 mL/kg of IBW
Set rate at desired minute ventilation/VT: The respiratory rate will be set to avoid air trapping
whenever possible as determined by the inspection of the flow tracing and/or measurements
of intrinsic PEEP.

1 PEEP Titration: Low PEEP/FiO2 Table

FiO2% 30 40 40 50 50 60 70 70 70 80 90 90 90 100
PEEP (cm H2O) 5 5 8 8 10 10 10 12 14 14 14 16 18 18-24

2 PEEP Titration: High PEEP/FiO2 Table

50- 100
FiO2% 30 30 30 30 30 30 40 40 50 50 80 90 100
80
PEEP (cm 5 8 10 12 14 14 16 16 18 20 14 22 22 22 24
H2O)

3 Paralysis
Use within the first 48 hours
Severe ARDS with PEEP/FiO2 <150
Intravenous injection of 20 mg of cisatracurium (may repeat if a decrease of the end-
inspiratory plateau pressure by less than 2 cm of water was noticed)
May use continuous infusion for paralysis
Ensure adequate sedation with RASS -4 to -5
3 Recruitment Maneuver
Moderate or severe ARDS
Continuous positive airway pressure (CPAP) mode and increase the pressure to 30–40 cmH2O
for 30–40 s
Monitor hemodynamics and possibility of pneumothorax
Caution in patients with preexisting hypovolemia or shock

4 Esophageal Pressure Monitoring

Moderate to severe ARDS or conditions with increase thoracic or intraabdominal pressures,
(i.e obesity)
B Transpulmonary Pressure Targets
Transpulmonary pressure in inspiration (Insp PL) <30
 Transpulmonary pressure in expiration (Exp PL): 0-10
Transpulmonary driving pressure (True Driving Pressure: DPtp) <15

C Contraindication to prone position

Increased ICP
Massive hemoptysis
Tracheal surgery or sternotomy <2 weeks
Facial trauma or surgery < 2 weeks including neck trauma or spinal instability
Pregnancy
DVT treated < 2days
large ventral surface burn
Cardiac pacemaker inserted < 2days
Unstable spine, pelvic, or femur fracture
Morbid obesity
Patients at high risk of requiring CPR or defibrillation
Staff judgement
5 Trial of prone position
Who to place in prone position?
• Patients with severe ARDS (PaO2/FiO2 < 150 mm Hg)
• Early in the course (ideally within 48 h)
• Best outcomes reported when prone positioning is used in combination with both
low tidal volume ventilation (6 cc/kg) and neuromuscular blockade
How to place patient in prone position?
• Requires 3-5 people, close attention to endotracheal tube (ETT) and central lines
• Preparation: preoxygenation, empty stomach, suction ETT/oral cavity, remove ECG
leads and reattach to back, repeated zeroing of hemodynamic transducers
• Support and frequently reposition pressure points: face, shoulder, anterior pelvis
How long to have patient in prone position each day?
• Successful trials use at least 16 hours of daily proning
• Long prone positioning sessions likely avoid derecruitment
When to stop?
• In PROSEVA, prone positioning was stopped when PaO2/FiO2 remained > 150 mm Hg
4 h after supinating (with PEEP < 10 cm H2O and FiO2 < 0.6)
• Optimal strategy is unclear: consider continuing prone positioning until clear
improvement in gas exchange, mechanics, and overall clinical course.
Potential complications
• Temporary increase in oral and tracheal secretions occluding airway
• ETT migration or kinking
• Vascular catheter kinking
• Elevated intraabdominal pressure
• Increased gastric residuals
• Facial pressure ulcers, facial edema, lip trauma from ETT, brachial plexus injury (arm
extension)
D ECMO Eligibility
Severe hypoxemia (PaO2/FiO2 ratio <80 mmHg) despite conventional and appropriate
therapies for at least 6 hours in acute reversible lung disease
Uncompensated hypercapnia with acedemia (pH <7.15) despite best accepted standard of
ventilatory care.
Presence of excessively high end-inspiratory plateau pressures (>35 cm H2O) despite best
accepted standard of ventilatory care.
No terminal disease (expected survival >6 months)
Intact neurological status
No limited vascular access
Respiratory support < 7 days (relative)
6 ECMO
http://www.nejm.org/doi/full/10.1056/NEJMct1103720

8 APRV
High airway pressure (Phigh) at the Pplat measured at the previous VCV settings +5 (not to
exceed 30 cmH2O)
Low airway pressure (Plow) at 5 cmH2O (minimal pressure level was used to prevent
atelectasis per standard practice)
Duration of release phase (Tlow) at one- to 1.5-fold the expiratory time constant, and then
adjust to achieve a termination of peak expiratory flow rate (PEFR) of ≥50% of PEFR
Release frequency at 10–14 frequency/min
Duration of Phigh (Thigh) is indirectly calculated based on the Tlow and release frequency
Spontaneous respiratory level targeted as spontaneous minute ventilation (MVspont),
approximately 30% total minute ventilation (MVtotal)
8 HFV
Bias flow 40 L/min
Inspiratory time 33%
mPaw 30 cm H2O
FIO2 1.0
Amplitude (delta P) 90 cm H2O.
Initial frequency based on most recent arterial blood gas:
• pH <7.10 = 4 Hz
• pH 7.10–7.19 = 5 Hz
• pH 7.20–7.35 = 6 Hz
• pH >7.35 = 7 Hz

8 Vasodilators: epoprostenol (aEPO)

Initiate aEPO at 50 ng/kg/min (based on ideal body weight – IBW, rounded to nearest 10kg)
via continuous nebulization with nebulizer connected to the ventilator
aEPO should be titrated downward every 30 minutes as tolerated to 10 ng/kg/min based on
PaO2 improvement.
Do NOT decrease aEPO by more than 10 ng/kg/min every 30 minutes
 https://www.universityhealthsystem.com/~/media/files/clinical-pathways/inhaled-
epoprostenol-guideline-1114.pdf?la=en

8 Tracheal Gas Insufflation (TGI)

https://www.atsjournals.org/doi/pdf/10.1164/ajrccm.162.2.9910111
 ARDS Criteria
Met

VT 4-6 mL/kg
PPL <30 Mode: PRVC or PC
A 1
Driving Pressure <15 PEEP: Low PEEP/FiO2 Table
SPO2 >88% on FiO2
<60% Maintain
√A
Yes

No

PEEP Titration
2
High PEEP/FiO2 Table

APRV Maintain
HFV √A
Bilevels Yes
8
Nitric Oxide No
TGI Alprostadil

Paralysis
3
Recruitment maneuver

Maintain
√A
6 ECMO Yes

No
Yes
No Transesophageal Pressure
4
Monitoring

ECMO Insp PL <30

D Exp PL 0-10
Eligible B √A
Yes DPtp <15

No No
No
Trial of Prone Yes Prone
Maintain 5 C
Yes Ventilation Eligible
√A