The Association of Off-hour Vs. On-hour Intensive Care Unit Admission Time with Mortality in Patients with Cardiogenic Shock: a Retrospective Multi-centre Analysis

Aims: Studies have shown a so-called off-hour effect for many different diseases, but data are scarce concerning cardiogenic shock. We therefore assessed the association of off-hour vs. on-hour intensive care unit admission with 30-day mortality in patients with cardiogenic shock.

Methods And Results: In total, 1720 cardiogenic shock patients (666 admitted during off-hours) from two large university hospitals in Germany were included in retrospect. An admission during off-hours was associated with increased 30-day mortality compared to an admission during on-hours [crude mortality 48% vs. 41%, HR 1.17 (1.03-1.33), P = 0.017]. This effect remained significant after propensity score matching (P = 0.023). Neither patients with a combined SCAI stage D and E (P = 0.088) or C (P = 0.548) nor those requiring cardiopulmonary resuscitation (P = 0.114) had a higher mortality at off-hour admission. In contrast, those without veno-arterial extracorporeal membrane oxygenation [HR 1.17 (1.00-1.36), P = 0.049], without acute myocardial infarction [HR 1.27 (1.02-1.56), P = 0.029] or a with combined SCAI stage A and B [HR 2.23 (1.08-4.57), P = 0.025] had an increased mortality at off-hour admission.

Conclusion: Our study showed an increased mortality in patients with cardiogenic shock admitted during off-hours, especially in those with a milder onset of disease. This stresses the importance of a thorough workup of each patient, especially at times of limited resources, the menace of underestimating the severity of cardiogenic shock, and the need for an improved 24×7 available risk stratification.