The Relationship of Nurse and Physician Staffing in Intensive Care Units with Patient Outcomes in Postoperative Patients on Ventilators: An Analysis Using Korean National Health Insurance Data

This study examined the associations of nurse and physician staffing in intensive care units (ICUs) with hospital-acquired pneumonia (HAP) incidence and in-hospital mortality in postoperative patients on ventilators. National Health Insurance claims data and death statistics were used to investigate the nurse staffing level and the presence or absence of a dedicated resident and specialist in each ICU. The participants were patients aged 20–85 who underwent any of 13 surgical procedures and were placed on a ventilator in the ICU after the procedure. Of 11,693 patients, 307 (2.6%) experienced HAP and 1280 (10.9%) died during hospitalization. Compared to hospitals with lower nurse-to-patient ratios, patients in hospitals with higher ratios had statistically significantly higher risks of HAP and in-hospital mortality. The presence of a dedicated resident in the ICU did not statistically significantly affect HAP incidence or in-hospital mortality. The presence of an ICU specialist was statistically significantly associated with in-hospital mortality but not HAP incidence. Our findings suggest that a higher level of nursing staff in the ICU is inversely associated with HAP incidence. The legal standards for nurse staffing in the ICU should be strengthened in order to improve the quality of care and patient safety.