To ventilate with pressure or volume; that is the question.

To ventilate with pressure control or volume control has been for decades a difficult question to answer. In a paper published in April issue of Chest, some authors

made a review to provide an evidence-based resolution to this debate.

Their approach to the question was ambitious and novel because the looked at physiologic outcomes as surrogates. In so doing they developed a physiologic quality assessment to screen studies for inclusion in their meta-analysis—a fairly novel idea. Others should look to do the same because it's important that we have an agreed-upon method for combining physiologic data and determining best practices. They also provide a nice, concise review of the nuances to each mode of ventilation, complete with figures of wave forms.

As for their results and conclusions, it would be too much to expect that they would provide a resolution to the debate. They found very little difference between pressure and volume modes of ventilation, regardless of the outcome examined. It seems clear that an insufficient flow rate during volume control can increase work of breathing in comparison with pressure control, in which the patient can control flow. However, if the flow rate is increased in the volume mode, there is no difference in work of breathing between modes. There was little evidence for differences between modes in gas exchange, compliance/elastance, or hemodynamics.