Study: Critical care bed availability affects postoperative admission decisions, but not outcomes

Editor's Note

Critical care bed availability influences whether patients are admitted to intensive care after surgery, but it does not significantly affect postoperative outcomes, according to a study published September 25 in the journal Anaesthesia.

The study involved 19,491 surgical patients from 248 hospitals in the UK, Australia, and New Zealand. It used instrumental variable analysis to examine how critical care bed availability impacts postoperative morbidity, with data collected from the SNAP-2 EPICCS observational study. Findings indicate that despite national guidelines recommending critical care for patients with a ≥5% estimated risk of mortality, many factors—including bed availability—shape these admission decisions.

More specifically, 10.8% of patients in the study were admitted to critical care immediately after surgery. The availability of beds increased the likelihood of critical care admission (odds ratio 1.04 per available bed), but this had no meaningful impact on postoperative morbidity at seven days, the study’s primary outcome. Patients admitted to critical care had higher rates of morbidity (38.4% vs. 11.6% in ward admissions) and mortality at 30 days (3.7% vs. 0.7%) and 60 days (3.9% vs. 0.8%), but this difference was largely attributed to patient risk factors rather than bed availability.

The analysis also found considerable variation between hospitals and surgical specialties in the probability of postoperative critical care admission, even after accounting for patient risk. Factors such as patient age, ASA physical status, surgical severity, and intraoperative blood loss played significant roles in determining admissions. However, the study revealed no clear evidence that critical care admissions directly reduced morbidity compared to patients admitted to regular wards.

Although critical care bed availability was shown to influence admission decisions, the effect was small compared to patient-specific factors. This suggests that while resource availability impacts decision-making, patient risk profiles remain the primary drivers of critical care admissions, researchers write. They call for more research, noting that “Our findings provide a rationale for a clinical trial which would evaluate any potential benefits for postoperative critical care admission for patients in whom there is no absolute indication for admission.”