Mechanical ventilation in post-AMICS cardiogenic shock

The following is an abstract of “Invasive mechanical ventilation in cardiogenic shock complicating acute myocardial infarction: a contemporary Danish cohort analysis,” published in the June 2024 issue of Cardiology by Povlsen et al.

Despite the widespread use of invasive mechanical ventilation (IMV) for cardiogenic shock resulting from acute myocardial infarction (AMICS), optimal treatment practices lack substantial evidence.

Researchers conducted a retrospective study to evaluate trends in VMI utilization, parameters, and short-term outcomes in patients with AMICS receiving VMI upon admission following out-of-hospital cardiac arrest (OHCA).

They studied consecutive patients with AMICS receiving VMI in an intensive care unit of two tertiary centers (2010 and 2017), with data analyzed on OHCA.

Results showed that 1,274 patients with VMI had AMICS, of whom 682 (54%) had an identified ACOH. The frequency of VMI increased during the study period due to a greater number of admissions for ACOH. In 566 patients with complete ventilator data, baseline 24-hour ICU monitoring included positive end-expiratory pressure, fraction of inspired oxygen, and minute ventilation. No difference in ventilator requirements was found between 30-day survivors and nonsurvivors with ACOH. In patients without ACOH, 30-day nonsurvivors had significantly higher ventilator requirements (P< 0.05), a lower PaO₂/FiO₂ ratio (median 143 versus 230, P< 0.001) and higher arterial lactate levels (median 3.5 vs 1.5 mmol/L, P< 0.001) than survivors. Normal PaO2₂ and pCO₂ levels were achieved in all patients, regardless of 30-day survival and OHCA status.

The researchers concluded that although patients with ACOH and non-ACOH AMICS initially achieved normal blood gas levels, only increased ventilation requirements in patients with non-ACOH ACOH predicted poorer survival.

Source: sciencedirect.com/science/article/pii/S0167527324003565