1. Medical air transportation with T-bird ventilator : don’t forget to input the cabin altitude! Jean-Pierre Tourtier, Thomas Leclerc, Marc Borne Military hospital Val-de-Grâce, Paris, France Service de Santé des Armées

2. Introduction (1):  Ventilator T-bird VS02  cabin altitude value should be manually input  Hypobaric  Vt set vs Vt delivered  With input of cabin altitude  Without input of cabin altitude

3. Introduction (2):

4. Methods (1):  Cabin altitude simulation

5. Methods (2):  Altitude simulated:  1500 m (4000 feet)  2500 m (6700 feet)  3000 m (3000 feet)

6. Methods (3):  Lung simulation: VT1 Bioteck  Normal lung: (resistance : 5.6 cm H 2 O/L/min ; compliance : 50 ml/cm H 2 O)

7. Methods (4):  Ventilation parameters: Vt set (ml)700, 400 Respiratory rate 12 I/E1/2 Fi02 (%)21,50,90

8. Methods (5):  Measurements:  Actual Vt: Fleisch pneumotachograph / computer  Actual respiratory rate  Statistical analyze:  3 measures  Mean +- SD  t test (Vt set vs Vt delivered): p <0.05

9. Results (1): T-bird VS02 with input of cabin altitude Vt=400 ml

10. Results (2): T-bird VS02 without input of cabin altitude Vt=400 ml

11. Results (3): T-bird VS02 with input of cabin altitude Vt=700 ml

12. Results (4): T-bird VS02 with input of cabin altitude Vt=700 ml

13. Discussion (1): T-bird VSO2: is it a « good » ventilator for air transport ?  With altitude: Vt decreased  Significantly: at 1500 m  > 10%: at 2500 m  don’t forget to input the cabin altitude!

14. Discussion (2): What is a « good » ventilator for ground transport?  Lightweight package  Small volume  Various possible settings  Settings: respected  EASY TO OPERATE  Evaluations Benchmarking Chipman et al. Performance comparison of 15 transport ventilators. Resp Care 2007

15. Discussion (3): specific stresses of flight  Vibration  Electromagnetic radiation  Electrical safety  Thermal and humidity conditions  Hypobaric 

16. Discussion (3): How to evaluate ?  Laboratory evaluation  Vibration  Electromagnetic radiation  Electrical safety  Thermal and humidity conditions  Hypobaric Few studies, no benchmarking Flynn et al. The performance of Dräger Oxylog ventilators at simulated altitude Anaesth Intensive Care 2008 Rodriquez et al. Effects of simulated altitude on ventilator performance. J Trauma 2009

17. Discussion (4): How to bring the evaluation to its completion ?  Real life  Systematic declaration of major dysfunction  Analyze of ventilators failures Root Cause Analysis Br Med J 2000; 320 :777-781 Ann Fr Anesth Réanim 2002; 21 : 509 - 516

18. Conclusion  Highly specialized ventilators: ≠ T-bird VS02  Evaluation  laboratory testing  real life  Highly trained personnel Johannigman JA. Critical care aeromedical teams (Ccatt): then, now and what's next J Trauma 2007