ahi score is an indication of the need for an increase in treatment thus based on the high ahi from the previous night the treatment pressure can be increased by some increment the treatment pressure increase is performed with the intent to decrease the ahi towards a clinically desirable level in the subsequent night the ideal treatment pressure will decrease the ahi to a clinically desirable level but not be so far in excess of the minimum required pressure that it induces unnecessary discomfort therefore the quantum of the incremental pressure increase may vary depending upon the perceived clinical severity of the ahi for example the choice of incremental pressure increase may reflect the clinical observation that a relatively small increment will induce a clinically significant change where the patient has a relatively low ahi e g a pressure increment of 0 5 cmh 2 o for an ahi in the range of 5 19 while a relatively larger increment will be appropriate to induce a clinically significant change where the patient has a relatively high ahi e g a pressure increment of 2 cmh 2 o for an ahi of 40 or higher referring to fig4 in the treatment pressure setting step 44 the treatment pressure is automatically set for the new session to be the previous session 39 s pressure setting plus the increment the treatment pressure will then be delivered during the current session in step 46 and then at step 48 the system cycles back to step 30 fig3 and again begins the process of determining a new ahi the new ahi will affect the treatment pressure for the next session or treatment in the next night or future session such.