A fixed inhaled nitrous oxide/oxygen mixture as an analgesic for adult cancer patients with breakthrough pain: study protocol for a randomized controlled trial

Table 1 Schedule of enrolment, interventions, and assessments

	Study period
	Enrolment	Post-allocation			Close-out
Timepoint	Diagnosed with breakthrough pain	Breakthrough pain episode (T0)	5 min after starting intervention (T1)	15 min after starting intervention (T2)	5 min after finishing intervention (T3)
Enrolment
Eligibility screen	√
Informed consent	√
Allocation	√
Interventions
Control group			√	√
Treatment groups			√	√
Assessments
Numerical pain rating scale		√	√	√	√
Blood pressure		√	√	√	√
Oxygen saturation		√	√	√	√
Heart rate		√	√	√	√
Satisfaction					√
Side effect			√	√	√

ISSN: 1745-6215