Risk factors for increased in-hospital mortality: a cohort study among cardiac surgery patients

Mortality is an important healthcare index for assessing the quality and the effectiveness of the provided nursing care.

The aim of this study was to identify the risk factors for increased in-hospital mortality among cardiac surgery patients.

We followed up prospectively 313 consecutive patients who were admitted to the cardiac surgery intensive care unit (ICU) of a general, tertiary hospital in Athens during a 1 year period. Data collection was performed by using a short questionnaire and two instruments, the Nursing Activities Score (NAS) and the logistic EuroSCORE for assessing the nursing workload (NWL) and the perioperative risk for each patient respectively.

Patients with a high 1st day NAS had an almost 3.3 times greater probability of death during their hospitalization (OR 3.3, 95%CI 1.4-8). Moreover, patients with increased perioperative risk (OR 4.2, 95%CI 1.50-12) and ICU length of stay (ICU-LOS) (OR 16.8, 95%CI 4.8-58.6) had statistically significant higher in-hospital mortality.

Increased level of NWL, patient perioperative risk and ICU-LOS are closely associated with increased in-hospital mortality of cardiac surgery patients. The correlation between NWL and mortality represents the strong link of the nursing profession with the improvement of the effectiveness and quality of care.