To determine the practicality of tissue oxygen StO2 measurements by Respiratory Care Practitioners (RCP’s) in critically ill patients.
Each patient in the Medical Intensive Care Unit (ICU) had a daily StO2 measurement using the Hutchinson Technology BioMeasurement Division’s InSpectra™ Tissue Spectrometer Model 325 (Hutchinson, MN 55350-9784) coupled to a standard bedside computer by the InSpectra™ OptoLink™ RS-232 cable. Two point calibrations were performed daily during start-up using the InSpectra™ Calibrator. The 25mm spacing InSpectra™ electrode was used within the standard InSpectra™ adhesive Shield. The Shield was left in place on the deltoid muscle of each patient between measurements.
Calibrator signals were reproducible day to day. There were no skin reactions to either the adhesive Shield or to the electrode’s near infrared signal. The RCP’s had no difficulty obtaining StO2 measurements from the deltoid muscle of each patient and downloading realtime StO2 measurements to the computer.CONCLUSIONS: 1. RCP’s can obtain StO2 measurements on critical care patients using the InSpectra™ Tissue Spectrometer and accessories; 2. RCP’s can download realtime InSpectra™ StO2 measurements to a computer’s serial data port for storage and analyses; 3. No adverse effects on ICU patients were noted from use of the InSpectra™ Tissue Spectrometer and accessories.
The StO2 of the deltoid muscle is a sensitive indicator of shock since StO2 predicts the balance between local oxygen delivery versus oxygen consumption. Both intermittent and continuous noninvasive StO2 measurements of the deltoid muscle performed by RCP’s should enhance ICU patient care and outcomes without adverse utilization of resources.
A.J. Marks, None.