PRE-FLIGHT PREPARATION

a. Ventilator

i. Most patients can be safely transported using the Impact 731 ventilator.

1. Allows for volume control or pressure control ventilation.

2. Altitude compensated.

3. Rated for patients 5kg and above.

a. For patients 5-30 Kg a 731 infant/pediatric circuit with 4.2ml of dead space should be utilized

b. Patients less than 5 Kg are usually transported by a Neonatal Transport Team.

4. Inverse ratio limited to I:E of 2:1

b. Oxygen

i. Oxygen requirements should be calculated for all patients.

1. Refer to Appendix A. ****Appendix A refers to the LTV 1000 ventilator and may no longer be applicable****

a. There is no safety factor in the calculations.

b. Additional oxygen beyond calculated requirement should be determined by each team on a case-by-case basis based on patient and transport characteristics.

ii. Each mechanically ventilated patient should ideally have a dedicated PTLOX.

iii. Aeromedical Evacuation AFIs support 2 patients on high-flow and recommend that 3rd patient should be on low-flow.

iv. The Aeromedical Evacuation team is responsible for allocating oxygen and will make that determination. CCATT, AE, and front-end Aircrew must work together to balance medical, logistic, and tactical challenges.

c. Patient Preparation

i. Patients with respiratory disease should be placed on the transport ventilator as soon as feasible by CCATT to ensure that the patient can be safely maintained on transport ventilator and allow time for an ABG to be drawn.

ii. Medical Teams that are preparing patients with respiratory dysfunction for transport within the next 24hrs should practice conservatively in managing these patients before flight.

1. Chest tubes should be left in place, particularly for patients on positive pressure ventilation. As patients climb in altitude, any residual pneumothorax may re-expand. Additionally, patients may require increasing ventilatory pressures to achieve oxygenation goals at altitude, putting the patient at risk for recurrent/worsening pneumothorax.

2. Patients on a ventilator typically should not be extubated immediately prior to transport. The decreased partial pressure of oxygen at altitude may not be easily overcome with non-invasive oxygenation. Additionally, transport can be painful and may require higher doses of pain medication. Both factors put a recently extubated patient at risk for respiratory insufficiency and reintubation.

iii. Review CXR

1. Note ETT depth and ensure correlation with CXR

2. Note invasive line positioning

3. Consider repeating CXR if more than 12 hrs. old or if clinical conditions have changed.

iv. Secure ET tube using a dedicated securing device.

1. If burns or facial trauma preclude this, consider securing tube to upper lateral incisor and adjoining canine tooth using silk suture or wire. Umbilical tape is also acceptable.

2. Be certain that lips and tongue are not injured by device.

v. Avoid exposing airway to atmospheric pressure during ventilator changeover if PEEP is ≥ 10cm H2O.

1. Lung de-recruitment occurs rapidly with exposure to atmospheric pressure.

2. Gently clamp ET tube using a Kelly clamp while the circuit is broken for ventilator changeover.

3. Pad the Kelly clamp with tape or short pieces of rubber tubing to avoid damage to the ET tube.

4. Do not clamp wire reinforced tubes as they will kink permanently.

vi. All ventilated patients should have a heat and moisture exchanger (HME) in place.

vii. Check ET tube cuff pressure prior to departure.

1. Proper ET tube cuff inflation is mandatory to avoid aspiration, de-recruitment and ventilator malfunction (pressure too low) or damage to tracheal mucosa (pressure too high).

2. Palpating ET tube cuff is inaccurate and should not be relied upon to estimate cuff pressure. Use a cuff manometer.

3. Goal Cuff Pressure is typically 20 – 30 cm H2O (15-22 mm Hg). Alternatively, the Minimal Leak Test should be used in pediatric patients and can be used safely in adults.

4. ET tube cuffs should be filled with air. Do not use saline.

viii. All ventilated patients should have the head of bed elevated at least 30° unless there is a contraindication.

1. Most patients will not have a contraindication. Ask the sending physician or neurosurgeon for clarification if necessary.

2. The backrest designed for the NATO litter is the most appropriate way to elevate the head of bed.

ix. All ventilated patients should have continuous ETCO2 monitoring.

1. Use caution interpreting the absolute value of the ETCO2 as it may not accurately reflect PaCO2.

a. The difference between PaCO2 and ETCO2 reflects dead space. A difference of 3-5 mmHg is normal in healthy patients. In critically ill patients this number can vary significantly and change rapidly with various disease processes.

b. The true value is the ability to immediately detect circuit disconnections and ventilator failures by observing changes in the waveform and to identify trends in CO2 that may prompt arterial blood gas measurement.

2. Should CPR be necessary, ETCO2 monitoring may be used to evaluate the adequacy of chest compressions, the goal is greater than 10 mmHg at a minimum and 20 mmHg ideally.

3. Additionally, ETCO2 waveforms may offer insight into a variety of respiratory dynamics.

x. All ventilated patients require gastric decompression at take-off and landing.

1. Large bore oro-gastric tubes are preferred to large bore naso-gastric tubes for decompression to reduce the risk of sinusitis.

2. For babies and others at risk of hypoglycemia, weigh the risks and benefits of discontinuing enteral feeds. If gastric feeds must be terminated, monitor patient for hypoglycemia and/or have a plan to mitigate this with dextrose containing fluids.

3. Patients with post pyloric feeding tubes and secured airways (ETT or Trach with cuff inflated) have a very low risk of aspiration and may continue enteral feeding.