Vascular Diseases
Conditions
Brief summary
Spontaneous myogenic oscillations will be studied under general anesthesia using finger photoplethysmography. This pilot study will explore potential physiological conditions that will effect the amplitude and/or frequency of myogenic oscillations.
Detailed description
This is a single center, nonrandomized, nonblinded, interventional clinical pilot research study that plans to enroll 40 patients. Study will be conducted while subjects are under general anesthesia. Myogenic oscillations will be measured using finger photoplethysmography. Changes in the amplitude and/or frequency of these oscillations will be analyzed in response to the interventions. Arterial blood pressure will be recorded to verify the efficacy of the interventions. Six different interventions that will either lower or increase blood pressure will be applied to the subjects. Each subject will receive 1 or 2 of the six interventions. Each of the 6 interventions will be applied to 8 subject. The interventions that the subject will not be randomized. They will be determined by the subjects blood pressure immediately before the intervention to guarantee that the blood pressure manipulations are within a safe range. Data will be analyzed offline using Matlab.
Interventions
DRUGPhenylephrine
blood pressure will be increased or decreased by using one of six interventions: phenylephrine (alpha-1 agonist), dexmedetomidine (alpha-2 agonist), clevidipine (Ca channel blocker, CaCl, tetanic stimulus and increase in venous pressure
DRUGDexmedetomidine
blood pressure will be increased or decreased by using one of six interventions: phenylephrine (alpha-1 agonist), dexmedetomidine (alpha-2 agonist), clevidipine (Ca
DRUGClevidipine
blood pressure will be increased or decreased by using one of six interventions: phenylephrine (alpha-1 agonist), dexmedetomidine (alpha-2 agonist), clevidipine (Ca
OTHERtetanic stimulus
A 5 second 70 mA tetanic stimulus will be applied to elicit peripheral vasoconstriction (stress response)
OTHERIncreased venous pressure
A 5 minute inflation of a noninvasive blood pressure cuff to 30 mmHg to increase venous pressure in the arm with the pulse oximeter probes.
DRUGCalcium Chloride
CaCl will be administered to increase blood pressure and plasma calcium concentration
Sponsors
University of California, San Francisco
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Over 18 yrs of age 2. Undergoing surgery in Moffitt-Long operating rooms 3. Receiving general anesthesia 4. Will have an intra-arterial catheter for clinical purposes 5. Able to consent in english
Exclusion criteria
1. Under 18 years of age 2. unable to provide informed consent 3. Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| myogenic oscillations | up to 5 minutes | change in amplitude and/of frequency of myogenic oscillations |
Countries
United States
Outcome results
None listed