The purpose of this research study is to measure rate of decline and pattern of tissue oxygenation using the device, ViOptix T.Ox. ViOptix probes will be secured to the arm and hand. The recording process on the ViOptix machine will begin and obtain baseline StO2 levels for 5 minutes. After 5 minutes, a blood pressure cuff will be inflated on one arm. This blood pressure cuff will be left inflated for 10-20 minutes. Every 2 minutes a pulse check or doppler exam will be performed at your wrist. Last, the cuff will be deflated and the you will be free to leave the study room.
Myocardial injury after non-cardiac surgery (MINS) is common in patients undergoing major surgery. Many of the events are undetected and associated with a high 30-day mortality risk. Knowledge of which perioperative factors that predicts MINS is lacking. Decrease in tissue oxygenation (StO2) is common in patients undergoing major spine surgery and is associated with postoperative complications in these patients. However, an association between decrease in tissue oxygenation and MINS has not been examined. This group of patients may have other potential predictors of postoperative complications that the study group would like to investigate. In this observational cohort study, we will include 70 patients undergoing major spine surgery at University of California San Francisco. The primary hypothesis is that decrease in intraoperative tissue oxygenation is associated with postoperative myocardial injury.
An observational study designed to evaluate the performance of a new Near Infrared Spectroscopy (NIRS) tissue oximeter device in the clinical setting, including a cerebral sensor and peripheral sensor. Fifty patients who are undergoing open-heart surgery will be enrolled and tissue oximetry measurement will be collected throughout the surgical procedure and for up to 24 hours following surgery. Tissue oximeter measurement of the brain and skeletal tissue will be added to the standard intra-operative patient monitoring. Measures of delirium will be collected using a standardized questionnaire. The relationship between cerebral oximetry measures and delirium scores will be explored.
The goal of this observational study is to learn if the measures of tissue oxygenation from the MIMOSA Pro imaging device correlate to standard vascular assessment tools in patients who receiving a lower extremity vascular assessment. The main questions it aims to answer are: * Do the MIMOSA Pro tissue oxygenation measures correlate to Ankle-Brachial Index, Toe-Brachial Index, transcutaneous oximetry, and Doppler wave forms? * Do the MIMOSA Pro tissue oxygenation measures correlate with disease classifications for peripheral arterial disease, venous disease, and wound stage? * Is the MIMOSA Pro able to measure vascular status more often than other modalities? Participants will be asked to follow standard of care, and also allow for their legs to imaged by the MIMOSA Pro.
Patients undergoing surgery on their Aorta can get ischemia, a lack of blood flow, to their intestines and colon. This is very serious, as 2 out of 3 patients who have this problem die before leaving the hospital. A device developed by Spectros, called T-Stat, is approved by the US FDA to detect ischemia, and has been reported to detect ischemia in AAA aneurysm surgery and stenting, allowing the surgeon or interventional radiologist to take action quickly, while the colon ischemia is still treatable. This purpose of this study is to establish how T-Stat can best be used to prevent deaths.
The overall purpose of this study is to evaluate maternal-fetal tissue light scattering properties. The objectives of the study are: (i) integrate established mathematical principles of oxygen saturation to model with increasing accuracy the "body in a body" problem of fetus in mother; similar to existing pulse oximeters, the calculations will be integrated into software in the final commercial product; (ii) obtain human measurements against which both computational models and animal data can be compared.
This study is being conducted to study light scattering properties of maternal-fetal tissue.
Controversy surrounds the use of regional cerebral oximetry (rSO2) as a measure of true cerebral oxygenation because of extracranial signal contamination and unmeasured confounding of cerebral a:v ratio. The measurement of brain tissue oxygen (PbrO2) has been used in routine neurosurgery and has been shown to reliably demonstrate cerebral hypoxia following severe head injury. It is the most direct measure of cerebral oxygenation. Here, we test the hypothesis that there is a correlation between PbrO2 and rSO2 under conditions of varying inspired oxygen fraction and the varying partial pressure of carbon dioxide in arterial blood in uninjured, normal human brain. Patients who are scheduled for elective removal of secondary cerebral metastases under general anesthesia will be recruited following written informed consent obtained by a study team member during their preoperative evaluation. BIS and rSO2 optodes will be applied, before induction of anesthesia, by a single researcher on both sides of the patient's forehead, as recommended by the manufacturer. General anesthesia will be maintained by total intravenous anesthesia (TIVA) with a combination of propofol (80-150 mcg/kg/min) and remifentanil (0.05-0.1 mcg/kg/min) targeted to a Bispectral Index range 40-60 (BIS; Covidien, Boulder, CO). Following craniotomy, the LICOX probe will be placed under direct vision into an area of normal brain within the tumor excision canal by the attending neurosurgeon. During a pause in surgery FIO2 and minute ventilation will be sequentially adjusted to achieve the following pairs of ventilation set points: 1) FIO2 0.3 and paCO2 30mmHg, 2) FIO2 1.0 and paCO2 40mmHg. After ≥5 minutes at each set point FIO2, PaCO2, rSO2 and PbrO2 will be recorded as a "snap-shot". A sample size of 15 achieves an 80% power with a one-sided type I error of 5% to detect a positive correlation of 0.6 (from the null hypothesis of no correlation) between changes in PbrO2 and changes in rSO2 subsequent on alterations made in ventilation strategy. Correlation will be measured using Pearson's Correlation. P values \< 0.05 will be considered statistically significant.
The goal of this observational study is to find out if researchers can measure oxygen consumption in the body without having to draw blood from lines in arteries and central veins. Participants will undergo measurements of arterial blood oxygen saturation using both finger and neck pulse oximeters.
Randomized, double-blind, placebo-controlled, pharmacokinetic, pharmacodynamic study. Subjects will be randomized to TSC or placebo to determine the effect of Trans Sodium Crocetinate (TSC) on Transcutaneous Oximetry Measurements (tcpO2) following a single administration of TSC in subjects breathing oxygen (O2).