Efficacy of Amflow®, a Real-Time-Portable Feedback Device for Delivering Appropriate Ventilation in Critically Ill Patients: A Randomised, Controlled, Cross-Over Simulation Study

Abstract

Objective . The aim of this study was to test whether Amflow® (a newly designed portable ventilation feedback device) can assist rescuers in delivering target tidal volume (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math>) and respiration rate (RR) during self-inflating bag (SB) ventilations in various clinical scenarios. Method . This was a simulation study with a prospective cross-over design. A total of 40 trained participants who underwent training for SB ventilation were recruited. Using a SB with or without Amflow® alternately, participants delivered ventilations to test lungs connected to a gas flow analyser in each of three different scenarios: acute respiratory distress syndrome (ARDS; 315–385 ml ranges for 350 ml target <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math>, with 20 breaths/min); cardiopulmonary resuscitation (CPR; 450–550 ml ranges for 500 ml target <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math> with 10 breaths/min); and adult head trauma (630–770 ml ranges for 700 ml target <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math> with 15 breaths/min). Results . The feedback group (SB with Amflow®) demonstrated a significantly higher percentage of delivering the appropriate <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math> ranges than the no-feedback group for both ARDS (58.6% versus 23.5%, respectively) and CPR (85.4% versus 41.0%, respectively) (all <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M6"><mml:mrow><mml:mi>p</mml:mi><mml:mo>&lt;</mml:mo><mml:mn>0.05</mml:mn></mml:mrow></mml:math>). However, there was no significant difference between the two groups in the percentage of delivering the appropriate <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M7"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math> ranges in head trauma patients (65.9% versus 68.3%, respectively; <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M8"><mml:mrow><mml:mi>p</mml:mi><mml:mo>=</mml:mo><mml:mn>0.092</mml:mn></mml:mrow></mml:math>). In all three scenarios, a higher percentage of target RR delivered was achieved in the feedback group (88.3%, 99.2%, and 96.3%, respectively) compared with the no-feedback group (5.8%, 12.5%, and 10.0%, respectively) (all <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M9"><mml:mrow><mml:mi>p</mml:mi><mml:mo>&lt;</mml:mo><mml:mn>0.05</mml:mn></mml:mrow></mml:math>). Conclusion . The Amflow® device could be useful for rescuers in delivering SB ventilation with appropriate <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M10"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math> and RR simultaneously in various critical situations, except for clinical cases that demand greater delivered <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M11"><mml:mrow><mml:msub><mml:mrow><mml:mi>V</mml:mi></mml:mrow><mml:mrow><mml:mtext>T</mml:mtext></mml:mrow></mml:msub></mml:mrow></mml:math>.

Topics & Concepts