Availability of intraarterial pressure waveforms from catheter-manometer systems during surgery

Area of Science:

• Anesthesiology
• Cardiovascular Surgery
• Critical Care Medicine

Background:

• Accurate intraarterial pressure monitoring is crucial during anesthesia and surgery.
• Intermittent unavailability of pressure waveforms can compromise patient management.
• Radial artery cannulation is a common method for invasive blood pressure monitoring.

Purpose of the Study:

• To quantify the frequency and duration of unavailable usable pressure waveforms from radial intraarterial cannulas.
• To compare waveform availability between systems with and without continuous flush devices.
• To identify the primary causes of pressure waveform unavailability.

Main Methods:

• Prospective observational study involving 41 patients undergoing anesthesia and surgery.
• Continuous monitoring of radial intraarterial pressure waveforms.
• Data collection on waveform availability, system type (continuous flush vs. non-continuous flush), and causes of unavailability.

Main Results:

• Usable arterial pressure was unavailable 8.7% of the time during cardiac surgery with continuous flush.
• Waveform unavailability was 9.1% during noncardiac surgery with continuous flush and 14.7% without continuous flush.
• Artifacts were the primary cause of unavailability, followed by flushing and blood sampling.

Conclusions:

• Continuous flush systems enhance the availability of intraarterial pressure waveforms during surgical procedures.
• Minimizing artifacts, flushing, and blood sampling can further improve data acquisition.
• Occasional use of a Riva-Rocci cuff does not significantly detract from the utility of intraarterial pressure monitoring.