Correlation between end-tidal carbon dioxide and the degree of compression of heart cavities measured by transthoracic echocardiography during cardiopulmonary resuscitation for out-of-hospital cardiac arrest

Table 4 CImax cut-off levels for prediction of EtCO₂ levels above different thresholds

EtCO₂ (mmHg)	CImax cut-off level (%)	Best Youden’s index	Sensitivity (%)	Specificity (%)	Positive predictive value	Negative predictive value
> 15	15.25	0.952	95.2	100.0	100.0	83.3
> 20	17.35	1.000	100.0	100.0	100.0	100.0
> 25	35.92	0.742	100.0	74.2	74.2	72.4

ISSN: 1364-8535