Table 2.

Order of experimental conditions

Order	Condition	Session
1	First ever breath-hold, with a maximum inflation with air	1
2	Instruction and training in breath-hold technique; patient connected to mechanical ventilator but only on the spontaneous setting, inhale, exhale, inhale maximally and then breath-hold from air after instruction	1
3	As (2) above, but after breathing 60% oxygen for 4 min, then breath-hold from 60% oxygen	1
4	As (3) above, but after 15 min of mechanical ventilation-induced hypocapnia with 60% oxygen, then breath-hold from 60% oxygen and hypocapnia	1
5	As (4) above, repeated as necessary for post-training breath-hold from 60% oxygen and hypocapnia	2–4
6	As (5) above, repeated in simulator room under simulated treatment conditions, then treatment table breath-hold from 60% oxygen and hypocapnia	5