Manually recorded oxygen saturation was higher compared to automated sampling. (Image source: Thinkstock)

Manually recorded oxygen saturation was higher compared to automated sampling. (Image source: Thinkstock)

When looking over a chart, can you believe the information recorded?  Dr. Andreas H. Taenzer, Department of Anesthesiology and Pediatrics, The Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, Lebanon, NH and colleagues compared manually charted oxygen saturation with saturations obtained from a continuous monitoring system obtained from patients whose oxygen saturation over a 15-minute period was less than 90%.  Their results are presented in the article “A Comparison of Oxygen Saturation Data in Inpatients with Low Oxygen Saturation Using Automated Continuous Monitoring and Intermittent Manual Data Charting” published in this month’s issue of Anesthesia & Analgesia.

The authors used data from surgical and medical units where a licensed nursing assistant recorded vital signs every 4 hours.  Data were obtained from 36 patients who had adverse events (defined by their need for activation of the institutional rapid response team).  The primary focus of the study was on patients whose oxygen saturation was less than 90% over a 15-minute time period.

Manually recorded oxygen saturation was higher than automated recording of oxygen saturation. More specifically, manually recorded saturations were on average 6.5% higher for the 5-minute interval around the recorded time of manual charting.  Differences averaged between 1.9% and 14.2%.

This was a study of recording accuracy.  The number of patients studied was small.  However, the study suggests observer bias towards recording more physiologically reassuring vital signs. As patient data are increasingly gathered directly from physiologic monitors, it is likely that our records will more accurately reflect the vital signs in physiologically compromised patients.