Intensive care unit versus high dependency care unit admission after emergency surgery: a nationwide in-patient...

The appropriate level of postoperative critical care for patients undergoing emergency surgery is unknown. We aimed to assess the outcomes of postoperative patients treated in the intensive care unit (ICU) and high dependency care unit (HDU) after emergency surgery.

Analysis of national in-patient registry data in Japan from July 2010 to March 2018, including patients undergoing one of 10 emergency surgeries on the day of hospital admission. The exposures were ICU or HDU admission on the day of surgery. The primary outcome was in-hospital mortality. We performed multivariable logistic regression analysis adjusted for patient and hospital characteristics. Results are presented as n (%) and odds ratios (ORs) with 95% confidence intervals.

We included 158 149 patients from 646 hospitals. Crude in-hospital mortality for each procedure ranged from 168/8583 (2.0%) for cholecystectomy to 2842/12 958 (21.9%) for patients undergoing surgery for traumatic brain injury. Compared with HDU admission, ICU admission was associated with lower in-hospital mortality among the cohorts for medium-mortality risk procedures (procedure-specific mortality 5-15%) (ICU: 8834/73 616 [12.0%] vs HDU: 2586/25 262 [10.2%]; OR=0.90 [0.85-0.96]; P=0.001), and high-mortality risk procedures (procedures-specific mortality >15%) (ICU: 3445/16 334 [21.1%] vs HDU: 996/4613 [21.6%]; OR=0.86 [0.78-0.96]; P=0.005). There were no differences in mortality for low-mortality risk procedures with procedure-specific mortality <5%.

In this national registry study, postoperative critical care in ICU was associated with lower in-hospital mortality than in HDU for patients undergoing medium-risk and high-risk emergency surgery. Further research is needed to understand the role of critical care for surgical patients.