From the Guidelines
The Volume Control Plus (VC+) mode on the Puritan Bennett 840 ventilator is a dual-control mode that combines features of both volume and pressure ventilation, delivering a set tidal volume while automatically adjusting the inspiratory pressure to achieve this target volume with minimal pressure. This mode is designed to provide breath-to-breath pressure adaptation, maintaining consistent tidal volumes while minimizing peak airway pressures. The VC+ mode includes safety features like maximum pressure limits to prevent barotrauma and monitors delivered volumes, adjusting accordingly if the patient's condition changes 1. The characteristics of the VC+ mode make it particularly beneficial for patients with changing lung mechanics, such as those recovering from acute respiratory distress syndrome or undergoing weaning from mechanical ventilation, as it provides the safety of volume-targeted ventilation while minimizing the risk of pressure-related lung injury through its adaptive pressure delivery. Some key considerations in the use of VC+ mode include:
- Setting appropriate tidal volumes, with recommendations suggesting 6-8mls/kg for obstructive disease and 6mls/kg for neuromuscular disease and chest wall deformity 1
- Adjusting respiratory rate and I:E ratio based on the patient's condition, with recommendations including rates of 10-15 for obstructive disease and 15-25 for neuromuscular disease and chest wall deformity 1
- Monitoring and adjusting inspiratory pressure to achieve the target tidal volume while minimizing peak airway pressures, with a goal of keeping peak airway pressure below 30 cmH2O to reduce the risk of ventilator-induced lung injury 1. Overall, the VC+ mode on the Puritan Bennett 840 ventilator is a versatile and adaptive mode of ventilation that can be tailored to the individual needs of patients with a range of respiratory conditions.
From the Research
Characteristics of Volume Control Plus Mode
The provided studies do not directly discuss the characteristics of the Volume Control Plus mode of ventilation on the Puritan Bennett 840.
Ventilation Modes and Strategies
- The studies focus on the use of positive end-expiratory pressure (PEEP) in mechanical ventilation for patients with acute respiratory distress syndrome (ARDS) 2, 3, 4, 5, 6.
- They discuss different strategies for setting PEEP levels, including the use of PEEP/FiO2 tables and mechanical parameters such as plateau pressure and respiratory system compliance 2, 4, 5.
- The studies also examine the effects of higher versus lower PEEP levels on clinical outcomes in patients with ARDS 3, 4, 5.
Limitations
- None of the studies provide information on the specific characteristics of the Volume Control Plus mode of ventilation on the Puritan Bennett 840.
- The studies are focused on the general management of mechanical ventilation in patients with ARDS, rather than the specific features of a particular ventilator mode.