Trial Outcomes & Findings for Effect of Location of Tetanic Stimuli on Photoplethysmogram Under General Anesthesia (NCT NCT05899686)

Results Overview

Tetanic stimulation will induce peripheral vasoconstriction. This will be measured using photoplethysmography. During peripheral vasoconstriction the light transmission through finger will increase. The primary outcome will be the maximum change in light transmission (as measured by photoplethysmography) within 60 seconds after a tetanic stimulus as compared to pre stimulus baseline values. These maximal light transmission changes will be compared between the three different tetanic stimulus sites

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

12 participants

Primary outcome timeframe

Maximum light transmission change from pre tetanic stimulus baseline within 60 seconds after the tetanic stimulus

Results posted on

2024-05-16

Participant Flow

Stimuli were administered to three locations: A, B and C. Thus, there were 6 possible location sequences. ABC, ACB, BAC, BCA, CAB and CBA. These six location sequences were randomized in blocks of six (one of each) o that the sequence itself would not generate a bias. Thus, with 12 participants, each location sequence had two participants enrolled. For analysis the data for each location was pooled, independent of the location sequence.

Participant milestones

Participant milestones
Measure	Tetanic Stimulus all participants receive the same intervention Tetanic Stimulus: 5 second 100 Hz 70 mA tetanic stimulus will be applied to each subject at three different anatomical locations. The order of the three locations will be randomized.
Overall Study STARTED	12
Overall Study COMPLETED	11
Overall Study NOT COMPLETED	1

Reasons for withdrawal

Reasons for withdrawal
Measure	Tetanic Stimulus all participants receive the same intervention Tetanic Stimulus: 5 second 100 Hz 70 mA tetanic stimulus will be applied to each subject at three different anatomical locations. The order of the three locations will be randomized.
Overall Study Protocol Violation	1

Baseline Characteristics

Effect of Location of Tetanic Stimuli on Photoplethysmogram Under General Anesthesia

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Tetanic Stimulus n=12 Participants all participants receive the same intervention Tetanic Stimulus: 5 second 100 Hz 70 mA tetanic stimulus will be applied to three different locations in a random order
Age, Categorical <=18 years	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	9 Participants n=5 Participants
Age, Categorical >=65 years	3 Participants n=5 Participants
Age, Continuous	48 years STANDARD_DEVIATION 19 • n=5 Participants
Sex: Female, Male Female	6 Participants n=5 Participants
Sex: Female, Male Male	6 Participants n=5 Participants
Region of Enrollment United States	12 participants n=5 Participants

PRIMARY outcome

Timeframe: Maximum light transmission change from pre tetanic stimulus baseline within 60 seconds after the tetanic stimulus

Tetanic stimulation will induce peripheral vasoconstriction. This will be measured using photoplethysmography. During peripheral vasoconstriction the light transmission through finger will increase. The primary outcome will be the maximum change in light transmission (as measured by photoplethysmography) within 60 seconds after a tetanic stimulus as compared to pre stimulus baseline values. These maximal light transmission changes will be compared between the three different tetanic stimulus sites

Outcome measures

Outcome measures
Measure	Tetanic Stimulus n=10 Participants all participants receive the same intervention Tetanic Stimulus: 5 second 100 Hz 70 mA tetanic stimulus will be applied to three different locations in a random order
Tetanic Stimulus Induced Change in Photoplethysmography Light Transmission (in Analog to Digital Units as Measured Using a Pulse Oximeter) From Pre Stimulus Baseline Location 1	-50 percentage change from baseline value Standard Deviation 19
Tetanic Stimulus Induced Change in Photoplethysmography Light Transmission (in Analog to Digital Units as Measured Using a Pulse Oximeter) From Pre Stimulus Baseline Location 2	-52 percentage change from baseline value Standard Deviation 18
Tetanic Stimulus Induced Change in Photoplethysmography Light Transmission (in Analog to Digital Units as Measured Using a Pulse Oximeter) From Pre Stimulus Baseline Location 3	-44 percentage change from baseline value Standard Deviation 19

Adverse Events

Tetanic Stimulus

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Pekka Talke

UCaliforniaSF

Phone: 4153063602

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place