Abstract
Background
Cardiogenic shock (CS) is a life-threatening disease with limited evidence-based treatment options. During CS an imbalance between myocardial oxygen supply and demand exists. Use of positive end-expiratory pressure (PEEP) during invasive mechanical ventilation may reduce left ventricular (LV) afterload and LV work and thereby lower myocardial oxygen consumption without compromising hemodynamics during CS. In a porcine model of CS we aimed to investigate if increasing levels of PEEP could reduce total cardiac minute work (CW), a surrogate marker for myocardial oxygen consumption, without compromising cardiac output (CO).
Methods
This was a prospective, experimental study in 60 kg female pigs (n=24). We induced CS by repeated injections of microspheres into the left main coronary artery. CS was defined as ≥30% reduction in CO or mixed venous saturation. PEEP was increased stepwise in 3-minute intervals to 5, 8, 10, 13 and 15 cmH2O. Hemodynamic data were obtained using an LV pressure-volume catheter. CW was calculated (pressure volume area*heart rate). Measurements were performed at all PEEP-levels in healthy state, 5 minutes (CS+60) and 60 minutes after onset of CS (CS+5)
Results
CS was successfully achieved in all animals and CO decreased from 4.5±1.0 L/min to 2.9±0.5 L/min at CS+5 and 3.1±0.9 L/min at CS+60. Increasing PEEP resulted in stepwise reductions in CW from 5 to 15 cmH2O in healthy state by 37% (683±221 versus 429±155 mmHg*L, p<0.01). at CS+5 by 12% (446±137 versus 393±128 mmHg*L, p<0.001) and at CS+60 by 13% (511±178 versus 448±155 mmHg*L, p<0.001), CO was reduced at PEEP 15 in healthy state (4.5 ± 1.6 vs 4.0 ± 1.2 L/min, p<0.05) but remained preserved at all PEEP levels during CS. LV afterload and LV preload were significantly reduced with increased PEEP levels. Cardiac efficiency was preserved during PEEP alterations at all timepoints.
Conclusion
Myocardial oxygen consumption as measured by CW was reduced with increasing PEEP levels in healthy state and in CS. Importantly, PEEP was safely administered and well tolerated during CS with preserved CO and cardiac efficiency.
Cardiogenic shock (CS) is a life-threatening disease with limited evidence-based treatment options. During CS an imbalance between myocardial oxygen supply and demand exists. Use of positive end-expiratory pressure (PEEP) during invasive mechanical ventilation may reduce left ventricular (LV) afterload and LV work and thereby lower myocardial oxygen consumption without compromising hemodynamics during CS. In a porcine model of CS we aimed to investigate if increasing levels of PEEP could reduce total cardiac minute work (CW), a surrogate marker for myocardial oxygen consumption, without compromising cardiac output (CO).
Methods
This was a prospective, experimental study in 60 kg female pigs (n=24). We induced CS by repeated injections of microspheres into the left main coronary artery. CS was defined as ≥30% reduction in CO or mixed venous saturation. PEEP was increased stepwise in 3-minute intervals to 5, 8, 10, 13 and 15 cmH2O. Hemodynamic data were obtained using an LV pressure-volume catheter. CW was calculated (pressure volume area*heart rate). Measurements were performed at all PEEP-levels in healthy state, 5 minutes (CS+60) and 60 minutes after onset of CS (CS+5)
Results
CS was successfully achieved in all animals and CO decreased from 4.5±1.0 L/min to 2.9±0.5 L/min at CS+5 and 3.1±0.9 L/min at CS+60. Increasing PEEP resulted in stepwise reductions in CW from 5 to 15 cmH2O in healthy state by 37% (683±221 versus 429±155 mmHg*L, p<0.01). at CS+5 by 12% (446±137 versus 393±128 mmHg*L, p<0.001) and at CS+60 by 13% (511±178 versus 448±155 mmHg*L, p<0.001), CO was reduced at PEEP 15 in healthy state (4.5 ± 1.6 vs 4.0 ± 1.2 L/min, p<0.05) but remained preserved at all PEEP levels during CS. LV afterload and LV preload were significantly reduced with increased PEEP levels. Cardiac efficiency was preserved during PEEP alterations at all timepoints.
Conclusion
Myocardial oxygen consumption as measured by CW was reduced with increasing PEEP levels in healthy state and in CS. Importantly, PEEP was safely administered and well tolerated during CS with preserved CO and cardiac efficiency.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Journal of the American College of Cardiology |
| Vol/bind | 83 |
| Nummer | 13, suppl |
| ISSN | 0735-1097 |
| DOI | |
| Status | Udgivet - apr. 2024 |
| Begivenhed | American College of Cardiology's 73rd Annual Scientific Session & Expo - Atlanta, USA Varighed: 6 apr. 2024 → 8 apr. 2024 |
Konference
| Konference | American College of Cardiology's 73rd Annual Scientific Session & Expo |
|---|---|
| Land/Område | USA |
| By | Atlanta |
| Periode | 06/04/2024 → 08/04/2024 |