Acute effects of positive end-expiratory pressure on left ventricle diastolic function in healthy subjects

Abstract

We evaluated the acute effect of the application of positive end-expiratory pressure (PEEP) on LV diastolic function in 10 healthy subjects. We assessed load dependent diastolic function by Doppler examination of transmitral flow and load independent diastolic function by color M-mode propagation velocity of early flow into the LV cavity (Vp). During the application of PEEP in comparison to the baseline, we found a significant reduction of the E wave peak velocity [79 (64-83) vs. 65 (57-72) cm/s; p = 0.028] and a significant reduction in Vp [84 (73-97) vs. 53 (48-66); p = 0.012]. Moreover, we found a significant reduction in left atrial area [15 (13-18) vs. 12 (10-14) cm(2); p = 0.018] and right atrial area [12 (11-15) vs. 11 (9-12) cm(2); p = 0.015]. No difference was found in global LV systolic function. The application of PEEP acutely modifies the diastolic flow pattern across the mitral valve, and reduces atrial dimensions.

State of the evidence: mechanical ventilation with PEEP in patients with cardiogenic shock

“…While these results are promising and suggest potential benefit for PEEP beyond respiratory support, other studies have not shown haemodynamic improvement with the use of PEEP 58 59. Of note, these authors found that PEEP was not associated with a functional decline in LV function at high levels of PEEP, and it was therefore considered safe in these group of patients.…”

Hemodynamic variations in arterial wave reflection associated with the application of increasing levels of PEEP in healthy subjects

“…Many studies have demonstrated that alveolar recruitment manoeuvres (using high levels of PEEP) increase right ventricular afterload and decrease right ventricular preload, similarly to a Valsalva effect 9 . Moreover, augmented intrathoracic pressure induced by high level of PEEP, decreases right ventricle and increases left ventricle end—diastolic volume (EDV) as described also by transmitral pulsed-wave Doppler (PW-D) 10 . At the same time, PEEP decrease left ventricle afterload 11 .…”

Speckle-Tracking Strain Imaging Identifies Alterations in Left Atrial Mechanics With General Anesthesia and Positive-Pressure Ventilation

“…13,14 Although anesthetics and positive end-expiratory pressure ventilation have been suggested to affect LA function and diastolic indices of the left ventricle, clinical studies in patients with underlying cardiac disease have shown conflicting results. [15][16][17][18][19][20] Given the growing prognostic value of atrial strain and diastolic function on perioperative outcomes after cardiac surgery, it is important to have a better understanding of the effects of general anesthesia (GA) and positive-pressure ventilation (PPV) on these indices in patients with cardiovascular disease. 8,14,[21][22][23] The primary aim of this study was to evaluate the effect of GA and PPV on LA mechanics, as measured by twodimensional speckle-tracking strain imaging, in patients undergoing cardiac surgery.…”