ABG improvement
Fifteen studies exhibited ABG improvement with a total number of interventions (n=1135). Based on the pooled analysis (Figure 3A), ET showed a non-significant difference in mean ABGs improvement compared to MT (SMD: 0.03; 95% CI -0.33 to 0.39; p = 0.87). However, highly significant heterogeneity (I2 = 89%, p < 0.00001) and publication bias were found (Figure 3B).