ONGOING MANAGEMENT

a. Airway Suctioning

i. Suctioning every 4 hours is appropriate without copious secretions or mucous plugging.

ii. Frequent suctioning may lead to lung de-recruitment and worsen gas exchange in patients with ARDS.

b. ETT Cuff Pressure

i. Significant changes may occur on ascent and descent. Cuff pressure increases with ascent and decreases with descent.

ii. Cuff pressure should be checked and documented with manometer before departure, at cruise altitude, during descent and after landing.

c. Management of Oxygen Desaturation

i. Increase FiO2 to 100% if patient is desaturating quickly while you work through evaluation.

1. FiO2 can be quickly weaned based on SpO2 once the patient is stable

2.Rule out equipment malfunction, loss of O2 supply, or circuit disconnect and ensure that the desired FiO2 is being delivered to the patient

ii. Confirm ET tube placement is in trachea using ETCO2 and note location at teeth/lip

iii. If desaturation is severe switch immediately to manual bag ventilation with high flow oxygen and PEEP valve.

1. Suction the airway (consider simultaneous bag ventilation) to verify patency and clear mucous plugs.

2.Consider the need for ETT exchange if it is difficult to pass a suction catheter through the ETT.

3. When attempting to clear thick adherent mucous secretions make sure that the Zoll 330 suction machine is pulling -120 cm H2O. It is often necessary to TEMPORARILY clamp all other devices attached to suction, particularly the pleurevac.

4.Be aware that aggressive suctioning can lead to de-recruitment and mucosal injury, worsening hypoxia

iv. If the patient is dyssynchronous with the ventilator:

1. Consider changing the ventilatory mode.

2. Rule out pneumothorax/hemothorax.

3. Review peak pressure trend if using volume cycled ventilation.

4. Review VT trend if using pressure control ventilation. VT will decrease if significant pneumothorax develops and ΔP is not changed.

5. Evaluate existing chest tubes for proper function.

6. Consider increasing sedation or adding paralytic.

7. Evaluate lungs with ultrasound.

8. Needle decompression of the chest and placement of a chest tube may be necessary if there is suspicion of pneumothorax and concurrent hemodynamic compromise.

9. Consider needle decompression of the contralateral lung. Trauma patients are at high risk of bilateral pneumothorax even if only one side of the thorax shows signs of trauma.

v. Consider increasing PEEP. Raising PEEP may take 30 min to improve SpO2.

vi. Consider recruitment maneuvers after increasing PEEP to next level on titration table.

1. Additional lung can sometimes be recruited using sustained inflations (recruitment maneuvers) of the lung, particularly in patients with an increased risk of atelectasis.

2. Current data does not support wide-spread use of recruitment maneuvers for hypoxia. The risks of barotrauma outweigh the minimal benefit seen in most cases and so recruitment maneuvers are largely avoided in routine ICU care.

3. Patients with ARDS, recent lung surgery, ongoing air-leak from pneumothorax, or under-resuscitation are at high risk for further injury.

4. A typical recruitment maneuver consists of inflation to 30-40 cm H2O for 30-40 seconds, which is difficult to do on transport ventilators.

5. Recruitment maneuvers increase intrathoracic pressure (by design) which can result in decreased cardiac output and hypotension. Monitor blood pressure closely and terminate any of the below recruitment maneuvers if hypotension develops.

6. Pragmatic recruitment maneuvers on the 731 may be performed by:

a. Volume control setting:

i.. Increase peep first to match anticipated final FiO2 setting per ARDSNet

ii. Increase tidal volume to 10ml/kg for 1 minute then reduce to prior volume

b. Pressure control setting:

i. Increase peep first to match anticipated final FiO2 setting per ARDSNet

ii. Set PIP to 30 cm H20

iii. Manual breath hold for 20sec on two consecutive breaths as tolerated by patient

7. Recruitment maneuver can be performed with bag-valve manual ventilation.

a. Set PEEP valve on bag-valve unit to 20 cm H2O.

b. Deliver five sequential breaths, each held for 5-8 seconds.

c. Clamp endotracheal tube while switching between ventilator and bag. Exposure to atmospheric pressure will quickly result in lung de-recruitment, hypoxemia and increased ventilator induced lung injury.

d. Monitoring Oxygen Utilization

i. When using PTLOX, periodically check amount of oxygen consumed.

ii. Oxygen consumption may vary between ventilators, even with the same settings.

iii. Leaks in system may cause excessive oxygen consumption.

iv. Comparing actual to predicted oxygen consumption will allow early detection of excess utilization that may necessitate troubleshooting, changes in management or diverting aircraft in extreme cases.