Abstract

Effect of Rapid Response System on Unplanned Intensive Care Unit Admission after Elective Surgery

Masayuki Akatsuka, Hiroomi Tatsumi, Shinichiro Yoshida, Satoshi Kazuma, Yoichi Katayama, Yuya Goto and Yoshiki Masuda

Objective: The purpose of this study was to clarify whether initiation of a rapid response system (RRS) affected the incidence of unplanned intensive care unit (ICU) admissions (UIAs) for treatment of organ dysfunction in the early postoperative period.
Methods: We retrospectively identified patients admitted unexpectedly to the ICU from general wards within the first 72 h after surgery between January 2006 and December 2017. Patients with UIAs were divided into two groups: a pre-RRS group (January 2006-May 2013); and a post-RRS group (June 2013-December 2017). We extracted data on the patients' characteristics, intraoperative status, and postoperative conditions. Student's t-test and Fisher’s exact test were used to compare the patients' characteristics and incidences of UIA in the pre- and post-RRS groups.
Results: Thirty-nine patients (0.06%) underwent UIAs from general wards within the first 72 h after surgery. Preanesthetic condition as evaluated by ASA-physical status (ASA-PS) was ≥ 2, showing that most patients displayed some form of pre-anesthetic complication. The most frequent reasons for UIA were hypoxia in 19 patients (48.7%), shock in 12 patients (30.8%), and disturbance of consciousness in 4 patients (10.3%). The mortality rate in the pre- RRS group was 11.5%. SOFA score was significantly lower in the post-RRS group than in the pre-RRS group. The odds ratio for UIA between the pre- and post-RRS groups was 0.756 (95% confidence interval: 0.388-1.471). This result was not significant, but introduction of an RRS may be associated with an up to 25% reduction in UIA.
Conclusion: Introduction of an RRS did not reduce the incidence of UIA significantly, but severity of organ failure in patients with UIA decreased, resulting in lower UIA-associated mortality. Introduction of an RRS and careful observation of respiration-associated vital signs are therefore crucial to prevent UIA and UIA-related mortality after elective surgery.