Supplementary Material for: Hypotension at Hospital Presentation and Post-Contrast Acute Kidney Injury following Computed Tomography with Contrast Media

<b><i>Introduction:</i></b> Post-contrast acute kidney injury (PC-AKI) is a major complication of contrast media usage; risks for PC-AKI are generally evaluated before computed tomography (CT) with contrast at the emergency department (ED). Although persistent hypotension (systolic blood pressure [sBP] &lt;80 mm Hg for 1 h) is associated with increased PC-AKI incidence, it remains unclear whether transient hypotension that is haemodynamically stabilized before CT is a risk of PC-AKI. We hypothesized that hypotension on ED arrival would be associated with higher PC-AKI incidence even if CT with contrast was performed after patients are appropriately resuscitated. <b><i>Methods:</i></b> This multicentre retrospective observational study was conducted at three tertiary care centres during 2013–2014. We identified 280 patients who underwent CT with contrast at the ED. Patients were classified into two groups based on sBP on arrival (&lt;80 vs. ≥80 mm Hg); hypotension was considered as transient because CT with contrast has always been performed after patients were stabilized at participating hospitals. PC-AKI incidence was compared between the groups; inverse probability weighting (IPW) was conducted to adjust background characteristics. <b><i>Results:</i></b> Eighteen patients were excluded due to chronic haemodialysis, cardiac arrest on arrival, or death within 72 h; 262 were eligible for this study. PC-AKI incidence was higher in the transient hypotension group than the normotension group {7/27 (28.6%) vs. 24/235 (10.2%), odds ratio (OR) 3.08 (95% confidence interval [CI] 1.18–8.03), <i>p</i> = 0.026}, which was confirmed by IPW (OR 3.25 [95% CI 1.99–5.29], <i>p</i> &lt; 0.001). <b><i>Conclusion:</i></b> Transient hypotension at the ED was associated with PC-AKI development.