• The Neopuff's PEEP valve is flow sensitive.

      Hawkes, Colin Patrick; Dempsey, Eugene Michael; Ryan, C Anthony; Department of Neonatology, Cork University Maternity Hospital, Cork, Ireland. (2011-03)
      The current recommendation in setting up the Neopuff is to use a gas flow of 5-15 L/min. We investigated if the sensitivity of the positive end expiratory pressure (PEEP) valve varies at different flow rates within this range.
    • The Neopuff's PEEP valve is flow sensitive.

      Hawkes, Colin Patrick; Dempsey, Eugene Michael; Ryan, C Anthony; Department of Neonatology, Cork University Maternity Hospital, Cork, Ireland. (2012-01-31)
      AIM: The current recommendation in setting up the Neopuff is to use a gas flow of 5-15 L/min. We investigated if the sensitivity of the positive end expiratory pressure (PEEP) valve varies at different flow rates within this range. METHODS: Five Neopuffs were set up to provide a PEEP of 5 cm H(2) O. The number of clockwise revolutions to complete occlusion of the PEEP valve and the mean and range of pressures at each quarter clockwise revolution were recorded at gas flow rates between 5 and 15 L/min. Results: At 5, 10 and 15 L/min, 0.5, 1.7 and 3.4 full clockwise rotations were required to completely occlude the PEEP valve, and pressures rose from 5 to 11.4, 18.4 and 21.5 cm H(2) O, respectively. At a flow rate of 5 L/min, half a rotation of the PEEP dial resulted in a rise in PEEP from 5 to 11.4cm H(2) O. At 10 L/min, half a rotation resulted in a rise from 5 to 7.7cm H(2) O, and at 15 L/min PEEP rose from 5 to 6.8cm H(2) O. CONCLUSION: Users of the Neopuff should be aware that the PEEP valve is more sensitive at lower flow rates and that half a rotation of the dial at 5 L/min gas flow can more than double the PEEP.
    • Potential hazard of the Neopuff T-piece resuscitator in the absence of flow limitation.

      Hawkes, C P; Oni, O A; Dempsey, E M; Ryan, C A; Department of Neonatology, Cork University Maternity Hospital, Wilton, Cork,, Ireland. (2012-01-31)
      OBJECTIVE: (1) To assess peak inspiratory pressure (PIP), positive end expiratory pressure (PEEP) and maximum pressure relief (P(max)) at different rates of gas flow, when the Neopuff had been set to function at 5 l/min. (2) To assess maximum PIP and PEEP at a flow rate of 10 l/min with a simulated air leak of 50%. DESIGN: 5 Neopuffs were set to a PIP of 20, PEEP of 5 and P(max) of 30 cm H(2)O at a gas flow of 5 l/min. PIP, PEEP and P(max) were recorded at flow rates of 10, 15 l/min and maximum flow. Maximum achievable pressures at 10 l/min gas flow, with a 50% air leak, were measured. RESULTS: At gas flow of 15 l/min, mean PEEP increased to 20 (95% CI 20 to 21), PIP to 28 (95% CI 28 to 29) and the P(max) to 40 cm H(2)O (95% CI 38 to 42). At maximum flow (85 l/min) a PEEP of 71 (95% CI 51 to 91) and PIP of 92 cm H(2)O (95% CI 69 to 115) were generated. At 10 l/min flow, with an air leak of 50%, the maximum PEEP and PIP were 21 (95% CI 19 to 23) and 69 cm H(2)O (95% CI 66 to 71). CONCLUSIONS: The maximum pressure relief valve is overridden by increasing the rate of gas flow and potentially harmful PIP and PEEP can be generated. Even in the presence of a 50% gas leak, more than adequate pressures can be provided at 10 l/min gas flow. We recommend the limitation of gas flow to a rate of 10 l/min as an added safety mechanism for this device.
    • Should the Neopuff T-piece resuscitator be restricted to frequent users?

      Hawkes, C P; Oni, O A; Dempsey, E M; Ryan, C A; Department of Neonatology, Cork University Maternity Hospital, Cork, Ireland. (2012-01-31)