Diurnal Variation in Mechanical Circulatory Support Initiation and Associated Outcomes

Area of Science:

• Cardiology
• Critical Care Medicine
• Medical Devices

Background:

• Mechanical circulatory support (MCS) is vital for cardiogenic shock and hemodynamic instability.
• Emergent MCS implantation often occurs off-hours, raising concerns about care delays and outcomes.
• Limited contemporary data exist on nighttime MCS initiation's impact.

Purpose of the Study:

• To assess if nighttime versus daytime MCS initiation affects mortality, complications, and time to care escalation.
• To investigate potential disparities in care associated with the timing of MCS device placement.

Main Methods:

• Retrospective cohort study using the MIMIC-IV database.
• Included adults undergoing first-time MCS placement during ICU admission.
• Categorized device initiations as daytime (06:00-17:59) or nighttime (18:00-05:59).
• Analyzed in-hospital mortality, acute kidney injury, bleeding, time to implantation, and postimplant survival using multivariable regression.

Main Results:

• 50.9% of 1120 MCS initiations occurred at night; baseline characteristics were similar.
• Nighttime initiation was not linked to increased in-hospital mortality (aOR 1.17; 95% CI 0.89-1.55).
• Rates of acute kidney injury and bleeding were comparable between groups.
• Median time from ICU admission to device placement was identical (1.4 hours) for both groups.

Conclusions:

• Nighttime MCS initiation is not associated with adverse outcomes or care delays.
• Contemporary ICUs demonstrate consistent readiness for advanced shock therapies 24/7.
• Findings suggest mitigation of traditional off-hours disparities in MCS care.