Life-threatening complications after postoperative intermediate care unit discharge: A retrospective, observational study.

BACKGROUND: Postoperative patients who require intensive monitoring, intervention with an arterial line, vasoactive drugs and prolonged ventilator weaning are admitted to the postoperative intermediate care unit (IMCU).

OBJECTIVES: The aim of this study was to estimate the prevalence of life-threatening complications within 7 days after IMCU discharge. Furthermore, we searched for associations between perioperative risk factors and these life-threatening complications.

DESIGN: A retrospective observational study.

SETTING: The postoperative IMCU of a university hospital in Tokyo, Japan, between 2010 and 2012.

PATIENTS: All adult patients who stayed in the postoperative IMCU and who were discharged to general wards without being transferred to the ICU were included.

MAIN OUTCOME MEASURES: A composite outcome of life-threatening complications needing unplanned ICU admission within 7 days after IMCU stay, or death within 7 days after IMCU stay.

RESULTS: Forty out of 3093 patients (1.3%) presented a life-threatening complication; all had an unplanned ICU admission, and none died. Patients with life-threatening complications had a longer length of hospital stay [median 38.0 (interquartile range, IQR 21.3 to 56.8) days vs. 12.0 (IQR 8.0 to 23.0), P < 0.001] and a higher in-hospital mortality (12.5 vs. 0.7%, P < 0.001). Independent risk factors were an emergency operation before IMCU admission [vs. elective; odds ratio (OR) 20.5; 95% confidence interval (95% CI) 12.2 to 36.0, P < 0.001], higher cumulative perioperative fluid load during the surgical operation and IMCU stay (3000 to 4999 vs. <1000 ml; OR 5.7; 95% CI 1.6 to 23.7, P = 0.009; ≥5000 vs. <1000 ml; OR 7.2; 95% CI 1.3 to 39.6, P = 0.021), mechanical ventilation during IMCU stay less than 6 h (vs. no use; OR 3.6; 95% CI 1.4 to 9.2, P = 0.007).

CONCLUSION: More than 1% of patients had a life-threatening complication within 7 days after IMCU discharge, but with no deaths. Risk factors were an emergency operation before IMCU admission, higher cumulative perioperative fluid load and a short period of mechanical ventilation during the IMCU stay.