Intraoperative Pleth Variability Index (PVI) Variability

Pleth Variability Index (PVI) is a variable that is derived from photoplethysmography (PPG) signal. It is used as a surrogate for intravascular volume status intraoperatively. PVI can have significant amount of baseline variability which appears to oscillate at a very low frequency (5-10 minute cycles). This study aims to investigate the origin of these baseline oscillations.

Study Overview

• Status: Terminated
• Conditions: Intraoperative Monitoring

Detailed Description

PVI is derived from the infrared photoplethysmography signal. Intraoperatively during mechanical ventilation it reflect fluid responsiveness which is a surrogate endpoint of intravascular volume.

PVI signal appears to have significant baseline variability which can not be explained by rapid changes in intravascular fluid volume. The baseline PVI changes also appear to oscillate at a very low frequency, much below any previously identified spontaneous vascular oscillations.

The aim of this study is to investigate weather the PVI variability originates from changes in the infrared photoplethysmography signal or if they are possibly due to the algorithm calculating PVI.

• Study Type: Observational
• Enrollment (Actual): 10

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94122
      • University of California San Francisco

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Neurosurgical and neurointerventional patients will be enrolled as these patients do rarely have sudden intravascular volume changes. Neurointerventional patients typically have no significant intravascular fluid changes, but do not routinely have intra-arterial catheters. Neurosurgical patients have slow, steady fluid shifts due to mannitol administration. Since most all of these patients have intra-arterial cannulas, it allows arterial waveform data collection which can be compared to the PPG signal.

Description

Inclusion Criteria:

• Neurosurgical patients for tumor resection
• neurointerventional patients
• general anesthesia with mechanical ventilation
• communicates in english (consent)
• over 18 years of age

Exclusion Criteria:

• unable to sign consent
• less than 18 years of age

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
neurosurgical patients; Neurosurgical patients undergoing craniotomies for tumor. 25 subjects
Neurointerventional patients; Patients undergoing neurointerventional procedures under general anesthesia. 25 subjects

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
PVI variability	PVI variability will be compare to raw infrared photoplethysmography signal	1 hour

Collaborators and Investigators

• Sponsor: University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2017
• Primary Completion (Actual): November 30, 2018
• Study Completion (Actual): November 30, 2018

Study Registration Dates

• First Submitted: July 9, 2017
• First Submitted That Met QC Criteria: July 9, 2017
• First Posted (Actual): July 12, 2017

Study Record Updates

• Last Update Posted (Actual): October 19, 2020
• Last Update Submitted That Met QC Criteria: October 15, 2020
• Last Verified: October 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: PT1701

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No