Peter Safar “We have defined ‘critical care medicine’ as the triad of: (1) resuscitation, (2) emergency care for life- threatening conditions, and (3) intensive care, including all components of the emergency and critical care medicine delivery system, pre-hospital and beyond.” Safar P. Crit Care Med 1974;2:1-5

Lung Protective Ventilation is Uncommon in Prehospital Patients being Transported by Air Ambulance Nicholas M. Mohr, MD Assistant Professor Department of Emergency Medicine Division of Critical Care, Department of Anesthesia University of Iowa Carver College of Medicine

Disclosure of Commercial Relationships No financial conflicts of interest to disclose

Background Gattinoni L. et al. CMAJ 2008;178:1174-6

Background Determann RM. et al. Crit Care 2010;14:R1 Low Tidal Volume (6 mg/kg) High Tidal Volume (10 mg/kg) n = 150

Background Mascia L. et al. JAMA 2010;304: n = 118

Background Fuller BM, Mohr NM, et al. Acad Emerg Med 2013;20: n = 251 Non-lung protective ventilation

Objectives (1)To describe current practice of mechanical ventilation in the prehospital aeromedical environment (2)To test the association between prehospital low tidal volume ventilation and ventilator-free days in intubated patients transported by air

Methods Study Design Retrospective cohort study of intubated adults (age ≥ 18) transported by air ambulance to 711-bed academic center (July 2011 – Apr 2013) who survived for at least 3 days after admission Photo courtesy AirCare ©, University of Iowa

Methods Outcomes 1)Descriptive statistics 2)28-day ventilator-free days Photo courtesy AirCare ©, University of Iowa

Total Intubated AirCare Patients n = 277 Missing Data n = 2 Died within 72 hours n = 80 Included Subjects n = 195 Results Factor Summary (n = 195) Age, mean (SD)53.9 (19.2) Male, n (%)108 (56) Scene17 (8.7) Weight, kg (mean, SD)81.2 (19.7) Height, in (mean, SD)66.7 (0.6) BMI, mean (SD)28.4 (6.8) APACHE-II, mean (SD)25.9 (7.8) Flight Time, min (mean, SD)26.2 (9.6) Vent-Free Days, mean (SD)21.0 (9.4) Mortality, n (%)31 (15.9)

Ventilator Mode BVM ventilation Vt = 610 ± 160 mL on manikin. ‡ ‡ Hess D, et al. Am J Emerg Med 1985;3: n = 40

Prehospital Tidal Volume Only 5% of selected tidal volumes were “lung protective” (≤ 8 mL/kg IBW) 498 ± 65 mL 10.5 ± 1.3 mL/kg IBW B AG -V ALVE

Tidal Volume and Obesity * p = 0.047

Oxygen Delivered

ED Tidal Volume Only 4% of selected tidal volumes were “lung protective” (≤ 8 mL/kg IBW) 541 ± 78 mL 11.2 ± 1.5 mL/kg IBW

Clinical Outcomes Clinical Outcome Low Tidal Volume (<10 mL/kg) (n = 21) Conventional Tidal Volume (≥ 10 mL/kg) (n = 19) p Ventilator-Free Days21.2 (9.2)21.3 (9.0)0.989 Hospital Length of Stay11.7 (8.2)11.4 (11.5)0.925 Mortality18 (86)16 (84)0.894

Conclusions Most ventilated patients are not transported on a ventilator in the helicopter Lung protective ventilation is rare in the prehospital environment and in the ED Clinical outcomes are not associated with prehospital ventilation strategy

Limitations Retrospective data collection Single center, single transport service Small sample size

Acknowledgements Terrence Wong, BA Andrew Stoltze, BA, JD Karisa K Harland, PhD Azeemuddin Ahmed, MD Brian Fuller, MD Funding: University of Iowa Carver College of Medicine, University of Iowa Department of Emergency Medicine, NHLBI Grant 5T35HL

Lung Protective Ventilation is Uncommon in Prehospital Patients being Transported by Air Ambulance Nicholas M. Mohr, MD Assistant Professor Department of Emergency Medicine Division of Critical Care, Department of Anesthesia University of Iowa Carver College of Medicine