PEEP titration in cardiogenic shock: impact on congestion and haemodynamic phenotype

AIMS: Optimal positive end-expiratory pressure (PEEP) selection in cardiogenic shock (CS) remains poorly defined despite the frequent use of invasive mechanical ventilation in this population. We aimed to evaluate whether a respiratory mechanics-guided PEEP titration protocol results in clinically relevant changes in ventilator settings and to assess the hemodynamic consequences of these adjustments. METHODS AND RESULTS: A prospective physiological study was conducted in mechanically ventilated patients with CS undergoing a decremental PEEP titration protocol (15 to 5 cmH2O). The final PEEP was selected according to maximal respiratory system compliance without evidence of derecruitment, overdistension, or hemodynamic deterioration. Hemodynamic, echocardiographic, and respiratory parameters were assessed at each step. Twenty-five patients were included, including 15 with acute myocardial infarction-related CS (AMI-CS) and 10 with heart failure-related CS (HF-CS). PEEP titration resulted in modification of ventilatory settings in 88% of patients. PEEP reduction occurred predominantly in AMI-CS, whereas PEEP escalation was more common in HF-CS. Respiratory mechanics and oxygenation improved following titration, with higher static compliance (62.5 ± 11 vs. 74.7 ± 11.5 mL/cmH2O; p = 0.003) and PaO2/FiO2 ratio (244 ± 89 vs. 276 ± 65; p = 0.001). Right atrial pressure (RAP) varied significantly across PEEP levels (p < 0.001) and changes were greater in HF-CS and in patients with RV dysfunction. Patients with impaired RV function showed greater RAP increase and reduced tolerance to higher PEEP levels. CONCLUSION: Respiratory mechanics-guided PEEP titration frequently modifies ventilatory settings in CS and reveals marked variability in hemodynamic tolerance according to CS phenotype and RV function. Individualized PEEP titration may help balance respiratory benefit, congestion, and hemodynamic stability in mechanically ventilated patients with cardiogenic shock.