predicted to lead to the goals in the example illustrated in table 2 the operator required solutions based upon the goals that paco 2 should be reduced from 58 to 54 mmhg v t should be u2266 6 ml kg and rr u2266 60 min u2212 1 t i 0 2 and t p 0 3 the computer returned the solutions in table 2 the operator judges the solutions in table 2 and may choose one that is implemented automatically or manually depending upon facilities offered by the properties of the apparatus the higher rr he is ready to accept the lower v t will be and the higher peep will be although lung protection would be optimal at solution 9 the operator might consider that a change of rr from 22 to 57 min u2212 1 is too drastic for accurate computer prediction of outcome he can then choose one of the less radical solutions and perform a new test later for a second step of resetting if he judges that no satisfactory solution is presented he might adjust goals and limits in order to explore other combinations of settings lov v t is a most important means behind lung protective ventilation accordingly the operator may wish to use a particular value for v t as a fixed goal from which the system predicts which values of paco 2 are to be expected at different values of rr table 3 shows an example based upon the same patient as in table 2 the operator has chosen to analyse a v t value of 5 5 ml kg from that value a preliminary value of v t co 2new is calculated according to.