Helicopter Transport of Ventilated Patients
Primary Recommendation
For helicopter transport of mechanically ventilated patients, use a portable transport ventilator rather than manual ventilation, ensure adequate oxygen reserves with a 30-minute safety margin, verify all ventilator settings before departure, optimize sedation to prevent patient-ventilator dyssynchrony, and have a competent physician escort who can manage airway emergencies. 1
Pre-Transport Preparation
Risk-Benefit Assessment
- Conduct a formal risk-benefit analysis before any transport decision, as the indication must justify exposing the patient to transport-related complications 1
- Stabilize the patient to achieve near-physiological homeostasis before transport, as patient factors rarely cause adverse events when adequate stabilization occurs 1
- Emergency transports carry significantly higher adverse event rates (7.8%) compared to pre-arranged transports (2.4%) 1
Airway Management Verification
- Secure the endotracheal tube with commercial devices or tape to prevent displacement during transport, as tube dislodgement is a major preventable complication 1
- Confirm correct tube positioning above the carina with chest x-ray when feasible before departure 1
- Ensure portable suction equipment is immediately available, as airway obstruction and secretion management are critical risks 1
Ventilator Settings Optimization
- Test all ventilator settings prior to departure including FiO₂, PEEP, respiratory frequency, exhaled tidal volume, airway pressure limits, and disconnection alarms 1, 2
- Portable ventilators have inferior triggering systems compared to ICU ventilators, requiring higher sedation levels to prevent patient-ventilator dyssynchrony 1, 2
- Set respiratory rate at 8-10 breaths per minute for patients with advanced airways during transport 1
- Maintain PEEP at individualized levels based on pre-transport requirements, noting that non-PEEP-compensated demand valves may require ventilator rate adjustments when PEEP exceeds 8 cm H₂O 3
Oxygen Supply Calculation
- Calculate oxygen requirements for the entire transport duration plus a mandatory 30-minute reserve 1
- Pneumatic ventilators require at least 50 bars pressure to deliver adequate tidal volumes 1
- A 1 m³ oxygen cylinder with turbine ventilators may only supply pure oxygen for less than 30 minutes independently 1
Sedation and Paralysis
- Optimize sedation or consider neuromuscular blockade based on clinical status to prevent patient agitation and ventilator dyssynchrony 1, 4
- Patient agitation and poor ventilator adaptation are linked to inadequate sedation levels during transport 1
- Consider using bispectral index monitoring during pre-transport rehearsal to ensure adequate sedation depth for psychological stress management 4
Transport Team Composition
Personnel Requirements
- A competent physician must escort the patient, as 83% of adverse events result from human error 1
- The escorting physician must be skilled in upper airway management, ventilator troubleshooting, and emergency interventions 1
- Limit personnel to essential team members only to reduce complexity and communication errors 1
- HEMS teams should ideally include board-certified anesthesiologists with intensive care training and significant HEMS experience 5
Equipment Requirements
Ventilator Selection
- Use automatic transport ventilators (ATVs) rather than manual ventilation for all transports, as ATVs provide superior oxygenation, constant tidal volume delivery, and regular respiratory cycles 1
- ATVs (pneumatically powered, time- or pressure-cycled) allow the team to perform other tasks while maintaining adequate ventilation 1
- Always have a bag-mask device available as backup in case of ventilator failure 1
- Transport ventilators should provide pressure-controlled ventilation and CPAP modes at minimum 5
Monitoring Equipment
- Continuous end-tidal CO₂ (ETCO₂) monitoring with capnography interpretation is mandatory 1, 2
- Monitor oxygen saturation, heart rate, blood pressure, and respiratory mechanics continuously 2, 6
- Document trends in ETCO₂ values rather than isolated readings to detect deterioration early 6, 7
Additional Equipment
- Portable suction unit with large-bore, non-kinking tubing and semirigid pharyngeal tips 1
- Defibrillator and emergency medications immediately accessible 1
- Battery-powered devices due to limited power supply in aircraft 4
During Transport Management
Continuous Monitoring
- Monitor for signs of ventilator-patient dyssynchrony, including agitation, tachypnea, and rising airway pressures 1, 2
- Verify adequate chest rise and ETCO₂ waveform continuously 1
- Assess for equipment malfunction including oxygen failure, ventilator alarms, and circuit disconnections 1, 7
Common Pitfalls to Avoid
- Avoid hyperventilation (>25 breaths/minute), as it increases intrathoracic pressure and reduces venous return and cardiac output 1
- Do not ignore untimely ventilator alarms, as they may indicate serious problems requiring immediate intervention 1
- Prevent accidental extubation by securing the tube properly and minimizing patient movement 1
- Ensure adequate tidal volume delivery at high peak inspiratory pressures, as portable ventilators may fail to maintain set volumes 3
Emergency Preparedness
- Have a predetermined plan for managing airway emergencies including accidental extubation, tube obstruction, and pneumothorax 1
- Know the location of wall suction, oxygen connectors, and emergency equipment at the destination 1
- Maintain communication with the receiving facility to ensure readiness for patient arrival 1
Special Considerations
High-Risk Patients
- Patients requiring FiO₂ >0.5 or PEEP >8 cm H₂O have higher risk of respiratory deterioration during transport 1, 3
- Patients on vasopressors or with multiple infusion pumps have increased equipment-related adverse event risk 1
- Severe acute respiratory distress syndrome patients may require specialty teams with advanced ventilator capabilities beyond standard transport ventilators 8
Environmental Factors
- Cabin space limitations in helicopters require careful equipment selection and positioning 4
- Altitude changes may affect ventilator performance and oxygen requirements 5
- Noise and vibration can interfere with monitoring and patient assessment 5
Post-Transport Care
Immediate Assessment
- Reassess airway position, ventilator settings, and hemodynamic stability immediately upon arrival 1
- Obtain arterial blood gas to verify adequate oxygenation and ventilation 3
- Screen for ventilator-associated pneumonia in the days following transport, as transport is a risk factor 1
Documentation
- Complete a transport form documenting indication, patient status before/during/after transport, adverse events, and interventions performed 1
- Track all personnel involved in transport to identify healthcare workers at risk if complications occur 1
Quality Improvement
Checklist Implementation
- Use a standardized checklist summarizing verification points before, during, and after transport to improve adherence to recommendations 1
- Checklists significantly reduce mortality and complications, as demonstrated in surgical settings 1
- Regular evaluation of transport practices should be undertaken to assess quality of care 1