Weaning from mechanical ventilation: old and new strategies

The strategies available for weaning patients from mechanical ventilation are many: T-piece mode, SIMV, PSV, and combinations of each. T-piece trials alternating with SIMV or AC provide periods of spontaneous breathing with rest on the ventilator. Decreasing SIMV rates gradually increases the patient's independence and spontaneous breathing; however, may result in an increased work of breathing with some systems. Alternatives such as flow-by and the addition of PSV may assist in the reduction of airway resistance. PSV weaning alone or in combination with SIMV or T-piece trials reduces work of breathing, promotes respiratory muscle training, and improves patient-ventilator interaction. Schuster states "the specific weaning technique employed is often less important than the care with which it is applied."