Frequency and Temporal Distribution of Postoperative Respiratory Depressive Events.

Area of Science:

• Anesthesiology
• Critical Care Medicine
• Patient Monitoring

Background:

• Postoperative respiratory depression (RD) is a significant concern, yet its frequency and temporal patterns remain incompletely understood.
• Continuous monitoring using capnography and pulse oximetry offers a method to investigate RD events in surgical patients.

Purpose of the Study:

• To determine the temporal distribution and frequency of respiratory depression episodes in postsurgical patients.
• To assess the relationship between the PRODIGY risk score and the incidence and number of RD episodes.

Main Methods:

• A post hoc analysis of data from 250 postsurgical patients enrolled in the PRODIGY trial.
• Continuous bedside monitoring with capnography and pulse oximetry on general care wards.
• Adjudication of data for RD episodes, classification of initial and all episodes, and calculation of PRODIGY risk scores.

Main Results:

• 2539 RD episodes were identified in 155 patients (62.0%).
• The median time to the initial RD episode was 8.8 hours postoperatively, with a peak occurrence between 14:00 and 20:00 on the day of surgery.
• Patients with high PRODIGY risk scores exhibited a higher incidence and greater number of RD episodes per patient (P < .001).

Conclusions:

• Continuous monitoring confirms that RD episodes are frequent in postsurgical patients.
• The risk of RD increases with higher PRODIGY risk scores.
• Initial RD episodes peaked in the afternoon/early evening, while all RD episodes peaked in the early morning.