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Randomized crossover trial to compare driving pressures in a closed-loop and a conventional mechanical ventilation
Gokhan Ceylan1,2, Sevgi Topal1, Gulhan Atakul1
1Department of Pediatric Intensive Care Unit, Dr Behcet Uz Children's Disease and Surgery Training and Research Hospital, Health Sciences University, Izmir, Turkey.
Insights
Driving pressure (ΔP) in Adaptive Support Ventilation (ASV) 1.1 was lower than in physician-tailored adaptive pressure-controlled mandatory ventilation (APV-CMV) in pediatric patients. ASV 1.1 offers safe ventilation for heterogeneous pediatric lung conditions.
Area of Science:
- Pediatric Critical Care Medicine
- Mechanical Ventilation Strategies
- Respiratory Physiology
Background:
- Driving pressure (ΔP) is a key stressor in mechanically ventilated patients, linked to ICU mortality.
- Adaptive Support Ventilation (ASV) 1.1 is an advanced algorithm designed to minimize both inspiratory pressure and work of breathing.
- Physician-tailored settings in APV-CMV may not consistently achieve optimal ΔP.
Purpose of the Study:
- To compare driving pressure (ΔP) between ASV 1.1 and physician-tailored APV-CMV in pediatric patients.
- To evaluate the efficacy of ASV 1.1 in reducing respiratory system stress.
- To assess the safety of ASV 1.1 in a heterogeneous pediatric patient population.
Main Methods:
- A randomized crossover trial involving 26 pediatric patients with heterogeneous lung disease requiring invasive mechanical ventilation.
- Two 60-minute ventilation periods were compared: ASV 1.1 and APV-CMV, with settings adjusted for equal minute ventilation.
- ΔP was calculated as the difference between plateau pressure and total PEEP.
Main Results:
- Median ΔP was significantly lower in ASV 1.1 (10.4 cmH2O) compared to APV-CMV (12.4 cmH2O) (p < .001).
- ASV 1.1 utilized a median tidal volume of 6.4 ml/kg at 41 breaths/min, while APV-CMV used 7.9 ml/kg at 31 breaths/min.
- Higher ΔP was observed in both modes for patients with restrictive lung conditions.
Conclusions:
- ASV 1.1 resulted in lower driving pressure compared to physician-tailored APV-CMV in pediatric patients with diverse lung conditions.
- ASV 1.1 demonstrates potential for safe and effective mechanical ventilation in this patient group.
- Further research may support ASV 1.1 as a preferred ventilation strategy for pediatric patients with heterogeneous lung disease.
Introduction:
In mechanically ventilated patients, driving pressure (ΔP) represents the dynamic stress applied to the respiratory system and is related to ICU mortality. An evolution of the Adaptive Support Ventilation algorithm (ASV® 1.1) minimizes inspiratory pressure in addition to minimizing the work of breathing. We hypothesized that ASV 1.1 would result in lower ΔP than the ΔP measured in APV-CMV (controlled mandatory ventilation with adaptive pressure ventilation) mode with physician-tailored settings. The aim of this randomized crossover trial was therefore to compare ΔP in ASV 1.1 with ΔP in physician-tailored APV-CMV mode.
Methods:
Pediatric patients admitted to the PICU with heterogeneous-lung disease were enrolled if they were ventilated invasively with no detectable respiratory effort, hemodynamic instability, or significant airway leak around the endotracheal tube. We compared two 60-min periods of ventilation in APV-CMV and ASV 1.1, which were determined by randomization and separated by 30-min washout periods. Settings were adjusted to reach the same minute ventilation in both modes. ΔP was calculated as the difference between plateau pressure and total PEEP measured using end-inspiratory and end-expiratory occlusions, respectively.
Results:
There were 26 patients enrolled with a median age of 16 (9-25 [IQR]) months. The median ΔP for these patients was 10.4 (8.5-12.1 [IQR]) and 12.4 (10.5-15.3 [IQR]) cmH2O in the ASV 1.1 and APV-CMV periods, respectively (p < .001). The median tidal volume (VT) selected by the ASV 1.1 algorithm was 6.4 (5.1-7.3 [IQR]) ml/kg and RR was 41 (33 50 [IQR]) b/min, whereas the median of the same values for the APV-CMV period was 7.9 (6.8-8.3 [IQR]) ml/kg and 31 (26-41[IQR]) b/min, respectively. In both ASV 1.1 and APV-CMV modes, the highest ΔP was used to ventilate those patients with restrictive lung conditions at baseline.
Conclusion:
In this randomized crossover trial, ΔP in ASV 1.1 was lower compared to ΔP in physician-tailored APV-CMV mode in pediatric patients with different lung conditions. The use of ASV 1.1 may therefore result in continued, safe ventilation in a heterogeneous pediatric patient group.
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