Evaluation of Ten Manual Resuscitators across an Operational Temperature Range of -18°C to 50°C

Because of the temperature extremes encountered during emergency resuscitation and transport in the field, we sought to evaluate the performance and safety of 10 adult resuscitators (5 permanent units: Hope 4, Laerdal, Lifesaver, Mark 3, and PMR; and 5 disposable units: BagEasy, Code Blue, CPR Bag, DMR, and SPUR) across an operational temperature range of -18°C to 50°C. METHOD: We tested the devices against the American Society for Testing and Materials (ASTM) Standard F-920 and the International Organization for Standardization (ISO) Standard 8382. We tested each resuscitator by using a lung model, the Bio-Tek VT-1 Ventilator Tester. RESULTS: All of the resuscitators met the ventilation requirements for Vr and f (600 mL × 20) and I:E < 1:1 except the SPUR at -18°C. Standards ASTM F-920 and ISO 8382 specify a fractional delivered oxygen concentration (FDO₂) of ≥ 0.85 with attachments and ≥ 0.40 without attachments at oxygen flow of 15 L/min and VE of 7.2 L/min (600 mL × 12). Nine resuscitators met Standards ASTM F-920 and ISO 8382 for FDO₂ with attachments at 21°C and 50°C, but only 3 units (Code Blue, DMR, and PMR) passed at -18°C. At 21°C, the Hope 4 had an FDO2 of 0.77 ± 0.03, which was significantly lower (p < 0.001) than that of the other 9 resuscitators, all of which were ≥ 0.93. Nine resuscitators met the FDO₂ standard without attachments. All 10 resuscitators passed the tests for valve function after contamination with simulated vomitus (at an oxygen flow of 30 L/min) and for backward leakage. At the ventilation pattern recommended by the American Heart Association (AHA) (800 mL × 12) the PMR's mean FDO₂ dropped to 0.86 ± 0.03 because of air leaking into the bag where it attaches to the patient-valve assembly. All 10 resuscitators passed the test for mechanical shock at 21°C and 50°C, but 3 units failed at -18°C. CONCLUSION: We conclude that only the Code Blue and DMR meet the ASTM and ISO standards for operator-powered adult resuscitators across the operational temperature range of -18°C to 50°C.