Risk factors associated with high postoperative ALT levels were longer LOS (p < 0.001, OR 2.992, 95% CI 1.635–6.477), longer duration of mechanical ventilation (p < 0.001, OR 7.56, 95% CI 3.494–16.355), longer ICU LOS (p < 0.001, OR 7.146, 95% CI 3.641–14.039), need for reintubation (p = 0.001, OR 12.941, 95% CI 2.957–56.642) and infection (p = 0.012, OR 3.454, 95% CI 1.135–9.078) in the univariate analyses (Table 2). Here, GPT is linked to infection.