Real-time changes in pulse pressure during a 10-second end-expiratory occlusion test reliably detect preload...

Area of Science:

• Critical care medicine
• Cardiovascular physiology
• Mechanical ventilation

Background:

• The end-expiratory occlusion (EEO) test assesses preload responsiveness by measuring changes in cardiac index (ΔCI).
• Investigating shorter EEO durations and the addition of end-inspiratory occlusion (EIO) can optimize this diagnostic tool.

Purpose of the Study:

• To evaluate the diagnostic accuracy of EEO-induced changes in arterial pulse pressure (∆PP) with reduced occlusion durations (10s and 5s).
• To determine if adding EIO improves the accuracy of the EEO test for preload responsiveness detection.

Main Methods:

• 143 mechanically ventilated patients in sinus rhythm underwent EEO and EIO tests.
• Preload responsiveness was defined by fluid bolus or passive leg raising-induced ΔCI.
• Changes in pulse pressure (∆PP) and cardiac index (ΔCI) were analyzed at various occlusion durations (15s, 10s, 5s).

Main Results:

• Both 15s and 10s EEO significantly increased ΔCI in preload responders compared to non-responders.
• ∆PP during 5s, 10s, and 15s EEO were significantly higher in responders.
• The diagnostic accuracy (AUROC) for ∆PP was high at 10s and 15s EEO, with no significant difference when EIO was added.

Conclusions:

• A 10-second EEO reliably detects preload responsiveness in ventilated patients with sinus rhythm.
• Real-time changes in arterial pulse pressure during EEO are effective for assessing fluid responsiveness.
• Reducing EEO duration to 10 seconds maintains diagnostic accuracy without compromising results.