A modified Trigg's Tracking Variable as an 'advisory' alarm during anaesthesia

Area of Science:

• Biomedical Engineering
• Physiology
• Anesthesiology

Background:

• Systolic blood pressure monitoring is critical in patient care.
• Early detection of blood pressure changes is essential for timely intervention.
• Existing methods for detecting blood pressure trends may have limitations.

Purpose of the Study:

• To evaluate the accuracy of a modified Trigg's Tracking Variable (TTV) algorithm.
• To compare the algorithm's performance against human expert (anesthesiologists) detection of systolic blood pressure changes.
• To assess the potential of TTV as an advisory alarm system.

Main Methods:

• A computer model simulated systolic blood pressure data with periods of stability and change.
• A modified Trigg's Tracking Variable (TTV) algorithm was developed to detect significant changes.
• Five anesthesiologists analyzed simulated data and identified the onset of blood pressure changes.
• Performance metrics included accuracy, detection rate, and delay in identifying trend onset.

Main Results:

• The modified TTV algorithm achieved 94.1% accuracy in detecting changes when exceeding a threshold of 0.92 for four consecutive determinations.
• The algorithm detected trend onsets with an average delay of 140 seconds.
• Anesthesiologists correctly identified 85% of changes with an average delay of 162 seconds.
• The TTV algorithm outperformed four out of five anesthesiologists in speed and accuracy.

Conclusions:

• The modified Trigg's Tracking Variable (TTV) algorithm demonstrates high accuracy and speed in detecting simulated systolic blood pressure changes.
• TTV-based trend detection systems show potential as effective advisory alarms in clinical settings.
• The algorithm offers a valuable tool for enhancing patient monitoring and safety.